A terrestrial biosphere model optimized to atmospheric CO2 concentration and above ground woody biomass

NASA Astrophysics Data System (ADS)

Saito, M.; Ito, A.; Maksyutov, S. S.

2013-12-01

This study documents an optimization of a prognostic biosphere model (VISIT; Vegetation Integrative Similator for Trace gases) to observations of atmospheric CO2 concentration and above ground woody biomass by using a Bayesian inversion method combined with an atmospheric tracer transport model (NIES-TM; National Institute for Environmental Studies / Frontier Research Center for Global Change (NIES/FRCGC) off-line global atmospheric tracer transport model). The assimilated observations include 74 station records of surface atmospheric CO2 concentration and aggregated grid data sets of above ground woody biomass (AGB) and net primary productivity (NPP) over the globe. Both the biosphere model and the atmospheric transport model are used at a horizontal resolution of 2.5 deg x 2.5 deg grid with temporal resolutions of a day and an hour, respectively. The atmospheric transport model simulates atmospheric CO2 concentration with nine vertical levels using daily net ecosystem CO2 exchange rate (NEE) from the biosphere model, oceanic CO2 flux, and fossil fuel emission inventory. The models are driven by meteorological data from JRA-25 (Japanese 25-year ReAnalysis) and JCDAS (JMA Climate Data Assimilation System). Statistically optimum physiological parameters in the biosphere model are found by iterative minimization of the corresponding Bayesian cost function. We select thirteen physiological parameter with high sensitivity to NEE, NPP, and AGB for the minimization. Given the optimized physiological parameters, the model shows error reductions in seasonal variation of the CO2 concentrations especially in the northern hemisphere due to abundant observation stations, while errors remain at a few stations that are located in coastal coastal area and stations in the southern hemisphere. The model also produces moderate estimates of the mean magnitudes and probability distributions in AGB and NPP for each biome. However, the model fails in the simulation of the terrestrial vegetation compositions in some grids. These misfits are assumed to derive from simplified representation in the biosphere model without the impact of land use change and dire disturbance and the seasonal variability in the physiological parameters.

DOE Office of Scientific and Technical Information (OSTI.GOV)

M. A. Wasiolek

The purpose of this report is to document the biosphere model, the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), which describes radionuclide transport processes in the biosphere and associated human exposure that may arise as the result of radionuclide release from the geologic repository at Yucca Mountain. The biosphere model is one of the process models that support the Yucca Mountain Project (YMP) Total System Performance Assessment (TSPA) for the license application (LA), the TSPA-LA. The ERMYN model provides the capability of performing human radiation dose assessments. This report documents the biosphere model, which includes: (1) Describing the referencemore » biosphere, human receptor, exposure scenarios, and primary radionuclides for each exposure scenario (Section 6.1); (2) Developing a biosphere conceptual model using site-specific features, events, and processes (FEPs), the reference biosphere, the human receptor, and assumptions (Section 6.2 and Section 6.3); (3) Building a mathematical model using the biosphere conceptual model and published biosphere models (Sections 6.4 and 6.5); (4) Summarizing input parameters for the mathematical model, including the uncertainty associated with input values (Section 6.6); (5) Identifying improvements in the ERMYN model compared with the model used in previous biosphere modeling (Section 6.7); (6) Constructing an ERMYN implementation tool (model) based on the biosphere mathematical model using GoldSim stochastic simulation software (Sections 6.8 and 6.9); (7) Verifying the ERMYN model by comparing output from the software with hand calculations to ensure that the GoldSim implementation is correct (Section 6.10); and (8) Validating the ERMYN model by corroborating it with published biosphere models; comparing conceptual models, mathematical models, and numerical results (Section 7).« less

Biogeosystem technique - the fundamental base of modern Water Policy and Management

NASA Astrophysics Data System (ADS)

Kalinitchenko, Valery; Batukaev, Abdulmalik; Minkina, Tatiana; Solntseva, Natalia; Skovpen, Andrey; Zarmaev, Ali; Jusupov, Vaha; Lohmanova, Olga

2014-05-01

Freshwater conservation is the problem of world water strategy. Water is intended not only for human consumption but also for functions of the biosphere - the only place where humanity can exist. To maintain the quality of biosphere is very relevant. An important property of biosphere is ability of soil to provide the synthesis of fresh living biological material by plants. There are few places in the world where exists a natural high level of biological production. Therefore, irrigation widely applies. Irrigation provides an increase of crops, but the imitating gravitational frontal isotropic-continual irrigation paradigm has the adverse effects on soils and landscapes. So irrigation in the past history of humanity was one of the causes for civilization's downfall, Sumer in particular, now irrigation causes a humanitarian catastrophe in Central Asia. Irrigation is the world main consumer of water. Leading cause of negative results of irrigation in biosphere is the irrigation paradigm defect. By artificial watering is imitated a natural hydrological regime of the land. The water flows down into soil through the soil surface. Or groundwater flows up through the soil bottom. In either case, a natural or standard artificial soil moisturizing amplifies the mass transfer in soil continuum. At initial soil stage the mass transfer in soil continuum plays positive role. Adverse substances are leached, in particular soluble salts. Fine material and organic particles determining soil fertility are accumulating. However, after a soil genesis initial stage the mass transfer through soil continuum plays negative role. Irrigation excess water flow into soil reduces the productivity of cultivated plants as compared to the optimum soil solution conditions. The excess soil moisture leads to excess transpiration, evaporation, infiltration, destroys the soil disperse system composition, forms inactive dead-end pores, leaches useful biological and other substances synthesized in soil out from active biosphere stage to vadose zone. These substances are entering the undesired stage of sedimentation and lithogenesis. Such adverse events are enhanced by irrigation. As a result, up to 80-90% of the fresh water taken for irrigation from lakes, rivers, storage reservoirs, desalinators are lost useless entailing economic losses. As a result of irrigation the quality of water is deteriorated as well as the quality of soil and landscape. A quality of human environment and a quality of biosphere as a whole is reduced. It is much more dangerous than economic losses. The irrigation paradigm shift is essential for successful water policy and water management in modern world. In a framework of Biogeosystem technics the new intrasoil pulse continuous-discrete paradigm of irrigation is developed. Water is supplied by small discrete portions into individual volumes of a soil continuum without excess soil mass transfer, transpiration, evaporation and seepage. New paradigm of irrigation optimizes plant growth, reduces consumption of water per unit of biological product, the yield increases. It provides the soil and landscape conservation, fresh water - the global deficit - saving up to 10-20 times, biological productivity and sustainability of biosphere. Intrasoil pulse continuous-discrete robotic irrigation technologies match the nowadays noosphere technological platform.

Global redox cycle of biospheric carbon: Interaction of photosynthesis and earth crust processes.

PubMed

Ivlev, Alexander A

2015-11-01

A model of the natural global redox cycle of biospheric carbon is introduced. According to this model, carbon transfer between biosphere and geospheres is accompanied by a conversion of the oxidative forms, presented by CO2, bicarbonate and carbonate ions, into the reduced forms, produced in photosynthesis. The mechanism of carbon transfer is associated with two phases of movement of lithospheric plates. In the short-term orogenic phase, CO2 from the subduction (plates' collisions) zones fills the "atmosphere-hydrosphere" system, resulting in climate warming. In the long-term quiet (geosynclynal) phase, weathering and photosynthesis become dominant depleting the oxidative forms of carbon. The above asymmetric periodicity exerts an impact on climate, biodiversity, distribution of organic matter in sedimentary deposits, etc. Along with photosynthesis expansion, the redox carbon cycle undergoes its development until it reaches the ecological compensation point, at which CO2 is depleted to the level critical to support the growth and reproduction of plants. This occurred in the Permo-Carboniferous time and in the Neogene. Shorter-term perturbations of the global carbon cycle in the form of glacial-interglacial oscillations appear near the ecological compensation point. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Solar UV dose patterns in Italy.

PubMed

Meloni, D; Casale, G R; Siani, A M; Palmieri, S; Cappellani, F

2000-06-01

Since 1992 solar ultraviolet (UV) spectral irradiance (290-325 nm) has been measured at two Italian stations of Rome (urban site) and Ispra (semirural site) using Brewer spectrophotometry. The data collected under all sky conditions, are compared with the output of a sophisticated radiative transfer model (System for Transfer of Atmospheric Radiation--STAR model). The STAR multiple scattering scheme is able to cope with all physical processes relevant to the UV transfer through the atmosphere. The experience so far acquired indicates that, in spite of the unavoidable uncertainties in the input parameters (ozone, aerosol, surface albedo, pressure, temperature, relative humidity, cloud cover), measured and computed clear sky iradiances are in reasonable agreement. The STAR model is applied to build up the solar UV geographic patterns in Italy: the daily dose in the range 290-325 nm is computed at about 70 sites where a thorough and homogeneous climatology is available. For each month the concept of an idealized "standard day" is introduced and the surface distribution of solar UV field determined. The map of solar UV patterns for Italy, available for the first time, meets the study requirements in the field of skin and eye epidemiology, as well as in other investigations dealing with the impact of UV on the biosphere. The results are interpreted in terms of atmospheric and meteorological parameters modulating UV radiation reaching the ground.

Recent developments in assessment of long-term radionuclide behavior in the geosphere-biosphere subsystem.

PubMed

Smith, G M; Smith, K L; Kowe, R; Pérez-Sánchez, D; Thorne, M; Thiry, Y; Read, D; Molinero, J

2014-05-01

Decisions on permitting, controlling and monitoring releases of radioactivity into the environment rely on a great variety of factors. Important among these is the prospective assessment of radionuclide behavior in the environment, including migration and accumulation among and within specific environmental media, and the resulting environmental and human health impacts. Models and techniques to undertake such assessments have been developed over several decades based on knowledge of the ecosystems involved, as well as monitoring of previous radionuclide releases to the environment, laboratory experiments and other related research. This paper presents developments in the assessment of radiation doses and related research for some of the key radionuclides identified as of potential significance in the context of releases to the biosphere from disposal facilities for solid radioactive waste. Since releases to the biosphere from disposal facilities involve transfers from the geosphere to the biosphere, an important aspect is the combined effects of surface hydrology, near-surface hydrogeology and chemical gradients on speciation and radionuclide mobility in the zone in which the geosphere and biosphere overlap (herein described as the geosphere-biosphere subsystem). In turn, these aspects of the environment can be modified as a result of environmental change over the thousands of years that have to be considered in radioactive waste disposal safety assessments. Building on the experience from improved understanding of the behavior of the key radionuclides, this paper proceeds to describe development of a generic methodology for representing the processes and environmental changes that are characteristic of the interface between the geosphere and the biosphere. The information that is provided and the methodology that is described are based on international collaborative work implemented through the BIOPROTA forum, www.bioprota.org. Copyright © 2013 Elsevier Ltd. All rights reserved.

Application of the Spanish methodological approach for biosphere assessment to a generic high-level waste disposal site.

PubMed

Agüero, A; Pinedo, P; Simón, I; Cancio, D; Moraleda, M; Trueba, C; Pérez-Sánchez, D

2008-09-15

A methodological approach which includes conceptual developments, methodological aspects and software tools have been developed in the Spanish context, based on the BIOMASS "Reference Biospheres Methodology". The biosphere assessments have to be undertaken with the aim of demonstrating compliance with principles and regulations established to limit the possible radiological impact of radioactive waste disposals on human health and on the environment, and to ensure that future generations will not be exposed to higher radiation levels than those that would be acceptable today. The biosphere in the context of high-level waste disposal is defined as the collection of various radionuclide transfer pathways that may result in releases into the surface environment, transport within and between the biosphere receptors, exposure of humans and biota, and the doses/risks associated with such exposures. The assessments need to take into account the complexity of the biosphere, the nature of the radionuclides released and the long timescales considered. It is also necessary to make assumptions related to the habits and lifestyle of the exposed population, human activities in the long term and possible modifications of the biosphere. A summary on the Spanish methodological approach for biosphere assessment are presented here as well as its application in a Spanish generic case study. A reference scenario has been developed based on current conditions at a site located in Central-West Spain, to indicate the potential impact to the actual population. In addition, environmental change has been considered qualitatively through the use of interaction matrices and transition diagrams. Unit source terms of (36)Cl, (79)Se, (99)Tc, (129)I, (135)Cs, (226)Ra, (231)Pa, (238)U, (237)Np and (239)Pu have been taken. Two exposure groups of infants and adults have been chosen for dose calculations. Results are presented and their robustness is evaluated through the use of uncertainty and sensitivity analyses.

Clustering XCO2 temporal change to assess CO2 exchanging strength of biosphere-atmosphere with GOSAT observations

NASA Astrophysics Data System (ADS)

He, Zhonghua; Lei, Liping; Bie, Nian; Yang, Shaoyuan; Wu, Changjiang; Zeng, Zhao-Cheng

2017-04-01

The temporal change of atmospheric carbon dioxide (CO2) concentration, greatly related to the local activities of CO2 uptake and emission, including biospheric exchange and anthropogenic emission, is one of important information for regions identification of carbon source and sink. Satellite observations of CO2 has been used for detecting the change of CO2 concentration for a long time. In this study, we used the grid data of column-averaged CO2 dry air mole fraction (XCO2) with the spatial resolution of 1 degree and the temporal resolution of 3 days from 1 June 2009 to 31 May 2014 over the land area of 30° - 60° N to implement a clustering of temporal changing characteristics for the Greenhouse Gases Observing Satellite (GOSAT) XCO2 retrievals. Grid data is derived using the gap filling method of spatio-temporal geostatistics. The clustering method is one adjusted K-mean for the gap existed time-series data. As a result, types and number of clusters are specified based on the temporal characteristic of XCO2 by using the optimal clustering parameters. The biospheric absorption and surface emission of atmospheric CO2 is discussed through the analysis of the different yearly increase and seasonal amplitude of XCO2 each cluster combined with correlation analysis with vegetation index from the Moderate-resolution Imaging Spectroradiometer (MODIS) and fossil fuel CO2 emission data from Open-source Data Inventory for Anthropogenic CO2 (Odiac). Regions of strong or weak biosphere-atmosphere exchange, or significant disturbance from anthropogenic activities can be identified. In conclusion, gap filled XCO2 from satellite observations can help us to take an analysis of atmospheric CO2, results of the coupled biosphere-atmosphere, by their spatio-temporal characteristics as well as the relationship with the other remote sensing parameters e.g. MODIS related with biospheric photosynthetic or respiration activities.

The Aggregate Representation of Terrestrial Land Covers Within Global Climate Models (GCM)

NASA Technical Reports Server (NTRS)

Shuttleworth, W. James; Sorooshian, Soroosh

1996-01-01

This project had four initial objectives: (1) to create a realistic coupled surface-atmosphere model to investigate the aggregate description of heterogeneous surfaces; (2) to develop a simple heuristic model of surface-atmosphere interactions; (3) using the above models, to test aggregation rules for a variety of realistic cover and meteorological conditions; and (4) to reconcile biosphere-atmosphere transfer scheme (BATS) land covers with those that can be recognized from space; Our progress in meeting these objectives can be summarized as follows. Objective 1: The first objective was achieved in the first year of the project by coupling the Biosphere-Atmosphere Transfer Scheme (BATS) with a proven two-dimensional model of the atmospheric boundary layer. The resulting model, BATS-ABL, is described in detail in a Masters thesis and reported in a paper in the Journal of Hydrology Objective 2: The potential value of the heuristic model was re-evaluated early in the project and a decision was made to focus subsequent research around modeling studies with the BATS-ABL model. The value of using such coupled surface-atmosphere models in this research area was further confirmed by the success of the Tucson Aggregation Workshop. Objective 3: There was excellent progress in using the BATS-ABL model to test aggregation rules for a variety of realistic covers. The foci of attention have been the site of the First International Satellite Land Surface Climatology Project Field Experiment (FIFE) in Kansas and one of the study sites of the Anglo-Brazilian Amazonian Climate Observational Study (ABRACOS) near the city of Manaus, Amazonas, Brazil. These two sites were selected because of the ready availability of relevant field data to validate and initiate the BATS-ABL model. The results of these tests are given in a Masters thesis, and reported in two papers. Objective 4: Progress far exceeded original expectations not only in reconciling BATS land covers with those that can be recognized from space, but also in then applying remotely-sensed land cover data to map aggregate values of BATS parameters for heterogeneous covers and interpreting these parameters in terms of surface-atmosphere exchanges.

Is the genetic landscape of the deep subsurface biosphere affected by viruses?

PubMed

Anderson, Rika E; Brazelton, William J; Baross, John A

2011-01-01

Viruses are powerful manipulators of microbial diversity, biogeochemistry, and evolution in the marine environment. Viruses can directly influence the genetic capabilities and the fitness of their hosts through the use of fitness factors and through horizontal gene transfer. However, the impact of viruses on microbial ecology and evolution is often overlooked in studies of the deep subsurface biosphere. Subsurface habitats connected to hydrothermal vent systems are characterized by constant fluid flux, dynamic environmental variability, and high microbial diversity. In such conditions, high adaptability would be an evolutionary asset, and the potential for frequent host-virus interactions would be high, increasing the likelihood that cellular hosts could acquire novel functions. Here, we review evidence supporting this hypothesis, including data indicating that microbial communities in subsurface hydrothermal fluids are exposed to a high rate of viral infection, as well as viral metagenomic data suggesting that the vent viral assemblage is particularly enriched in genes that facilitate horizontal gene transfer and host adaptability. Therefore, viruses are likely to play a crucial role in facilitating adaptability to the extreme conditions of these regions of the deep subsurface biosphere. We also discuss how these results might apply to other regions of the deep subsurface, where the nature of virus-host interactions would be altered, but possibly no less important, compared to more energetic hydrothermal systems.

Is the Genetic Landscape of the Deep Subsurface Biosphere Affected by Viruses?

PubMed Central

Anderson, Rika E.; Brazelton, William J.; Baross, John A.

2011-01-01

Viruses are powerful manipulators of microbial diversity, biogeochemistry, and evolution in the marine environment. Viruses can directly influence the genetic capabilities and the fitness of their hosts through the use of fitness factors and through horizontal gene transfer. However, the impact of viruses on microbial ecology and evolution is often overlooked in studies of the deep subsurface biosphere. Subsurface habitats connected to hydrothermal vent systems are characterized by constant fluid flux, dynamic environmental variability, and high microbial diversity. In such conditions, high adaptability would be an evolutionary asset, and the potential for frequent host–virus interactions would be high, increasing the likelihood that cellular hosts could acquire novel functions. Here, we review evidence supporting this hypothesis, including data indicating that microbial communities in subsurface hydrothermal fluids are exposed to a high rate of viral infection, as well as viral metagenomic data suggesting that the vent viral assemblage is particularly enriched in genes that facilitate horizontal gene transfer and host adaptability. Therefore, viruses are likely to play a crucial role in facilitating adaptability to the extreme conditions of these regions of the deep subsurface biosphere. We also discuss how these results might apply to other regions of the deep subsurface, where the nature of virus–host interactions would be altered, but possibly no less important, compared to more energetic hydrothermal systems. PMID:22084639

Estimation of Pre-industrial Nitrous Oxide Emission from the Terrestrial Biosphere

NASA Astrophysics Data System (ADS)

Xu, R.; Tian, H.; Lu, C.; Zhang, B.; Pan, S.; Yang, J.

2015-12-01

Nitrous oxide (N2O) is currently the third most important greenhouse gases (GHG) after methane (CH4) and carbon dioxide (CO2). Global N2O emission increased substantially primarily due to reactive nitrogen (N) enrichment through fossil fuel combustion, fertilizer production, and legume crop cultivation etc. In order to understand how climate system is perturbed by anthropogenic N2O emissions from the terrestrial biosphere, it is necessary to better estimate the pre-industrial N2O emissions. Previous estimations of natural N2O emissions from the terrestrial biosphere range from 3.3-9.0 Tg N2O-N yr-1. This large uncertainty in the estimation of pre-industrial N2O emissions from the terrestrial biosphere may be caused by uncertainty associated with key parameters such as maximum nitrification and denitrification rates, half-saturation coefficients of soil ammonium and nitrate, N fixation rate, and maximum N uptake rate. In addition to the large estimation range, previous studies did not provide an estimate on preindustrial N2O emissions at regional and biome levels. In this study, we applied a process-based coupled biogeochemical model to estimate the magnitude and spatial patterns of pre-industrial N2O fluxes at biome and continental scales as driven by multiple input data, including pre-industrial climate data, atmospheric CO2 concentration, N deposition, N fixation, and land cover types and distributions. Uncertainty associated with key parameters is also evaluated. Finally, we generate sector-based estimates of pre-industrial N2O emission, which provides a reference for assessing the climate forcing of anthropogenic N2O emission from the land biosphere.

Mapping Surface Cover Parameters Using Aggregation Rules and Remotely Sensed Cover Classes. Version 1.9

NASA Technical Reports Server (NTRS)

Arain, Altaf M.; Shuttleworth, W. James; Yang, Z-Liang; Michaud, Jene; Dolman, Johannes

1997-01-01

A coupled model, which combines the Biosphere-Atmosphere Transfer Scheme (BATS) with an advanced atmospheric boundary-layer model, was used to validate hypothetical aggregation rules for BATS-specific surface cover parameters. The model was initialized and tested with observations from the Anglo-Brazilian Amazonian Climate Observational Study and used to simulate surface fluxes for rain forest and pasture mixes at a site near Manaus in Brazil. The aggregation rules are shown to estimate parameters which give area-average surface fluxes similar to those calculated with explicit representation of forest and pasture patches for a range of meteorological and surface conditions relevant to this site, but the agreement deteriorates somewhat when there are large patch-to-patch differences in soil moisture. The aggregation rules, validated as above, were then applied to remotely sensed 1 km land cover data set to obtain grid-average values of BATS vegetation parameters for 2.8 deg x 2.8 deg and 1 deg x 1 deg grids within the conterminous United States. There are significant differences in key vegetation parameters (aerodynamic roughness length, albedo, leaf area index, and stomatal resistance) when aggregate parameters are compared to parameters for the single, dominant cover within the grid. However, the surface energy fluxes calculated by stand-alone BATS with the 2-year forcing, data from the International Satellite Land Surface Climatology Project (ISLSCP) CDROM were reasonably similar using aggregate-vegetation parameters and dominant-cover parameters, but there were some significant differences, particularly in the western USA.

Evidence for an active rare biosphere within freshwater protists community.

PubMed

Debroas, Didier; Hugoni, Mylène; Domaizon, Isabelle

2015-03-01

Studies on the active rare biosphere at the RNA level are mainly focused on Bacteria and Archaea and fail to include the protists, which are involved in the main biogeochemical cycles of the earth. In this study, the richness, composition and activity of the rare protistan biosphere were determined from a temporal survey of two lakes by pyrosequencing. In these ecosystems, the always rare OTUs represented 77.2% of the total OTUs and 76.6% of the phylogenetic diversity. From the various phylogenetic indices computed, the phylogenetic units (PUs) constituted exclusively by always rare OTUs were discriminated from the other PUs. Therefore, the rare biosphere included mainly taxa that are distant from the reference databases compared to the dominant ones. In addition, the rarest OTUs represented 59.8% of the active biosphere depicted by rRNA and the activity (rRNA:rDNA ratio) increased with the rarity. The high rRNA:rDNA ratio determined in the rare fraction highlights that some protists were active at low abundances and contribute to ecosystem functioning. Interestingly, the always rare and active OTUs were characterized by seasonal changes in relation with the main environmental parameters measured. In conclusion, the rare eukaryotes represent an active, dynamic and overlooked fraction in the lacustrine ecosystems. © 2015 John Wiley & Sons Ltd.

Modeling the impact of climate change in Germany with biosphere models for long-term safety assessment of nuclear waste repositories.

PubMed

Staudt, C; Semiochkina, N; Kaiser, J C; Pröhl, G

2013-01-01

Biosphere models are used to evaluate the exposure of populations to radionuclides from a deep geological repository. Since the time frame for assessments of long-time disposal safety is 1 million years, potential future climate changes need to be accounted for. Potential future climate conditions were defined for northern Germany according to model results from the BIOCLIM project. Nine present day reference climate regions were defined to cover those future climate conditions. A biosphere model was developed according to the BIOMASS methodology of the IAEA and model parameters were adjusted to the conditions at the reference climate regions. The model includes exposure pathways common to those reference climate regions in a stylized biosphere and relevant to the exposure of a hypothetical self-sustaining population at the site of potential radionuclide contamination from a deep geological repository. The end points of the model are Biosphere Dose Conversion factors (BDCF) for a range of radionuclides and scenarios normalized for a constant radionuclide concentration in near-surface groundwater. Model results suggest an increased exposure of in dry climate regions with a high impact of drinking water consumption rates and the amount of irrigation water used for agriculture. Copyright © 2012 Elsevier Ltd. All rights reserved.

Derivation of global vegetation biophysical parameters from EUMETSAT Polar System

NASA Astrophysics Data System (ADS)

García-Haro, Francisco Javier; Campos-Taberner, Manuel; Muñoz-Marí, Jordi; Laparra, Valero; Camacho, Fernando; Sánchez-Zapero, Jorge; Camps-Valls, Gustau

2018-05-01

This paper presents the algorithm developed in LSA-SAF (Satellite Application Facility for Land Surface Analysis) for the derivation of global vegetation parameters from the AVHRR (Advanced Very High Resolution Radiometer) sensor on board MetOp (Meteorological-Operational) satellites forming the EUMETSAT (European Organization for the Exploitation of Meteorological Satellites) Polar System (EPS). The suite of LSA-SAF EPS vegetation products includes the leaf area index (LAI), the fractional vegetation cover (FVC), and the fraction of absorbed photosynthetically active radiation (FAPAR). LAI, FAPAR, and FVC characterize the structure and the functioning of vegetation and are key parameters for a wide range of land-biosphere applications. The algorithm is based on a hybrid approach that blends the generalization capabilities offered by physical radiative transfer models with the accuracy and computational efficiency of machine learning methods. One major feature is the implementation of multi-output retrieval methods able to jointly and more consistently estimate all the biophysical parameters at the same time. We propose a multi-output Gaussian process regression (GPRmulti), which outperforms other considered methods over PROSAIL (coupling of PROSPECT and SAIL (Scattering by Arbitrary Inclined Leaves) radiative transfer models) EPS simulations. The global EPS products include uncertainty estimates taking into account the uncertainty captured by the retrieval method and input errors propagation. A sensitivity analysis is performed to assess several sources of uncertainties in retrievals and maximize the positive impact of modeling the noise in training simulations. The paper discusses initial validation studies and provides details about the characteristics and overall quality of the products, which can be of interest to assist the successful use of the data by a broad user's community. The consistent generation and distribution of the EPS vegetation products will constitute a valuable tool for monitoring of earth surface dynamic processes.

Multi-site assimilation of a terrestrial biosphere model (BETHY) using satellite derived soil moisture data

NASA Astrophysics Data System (ADS)

Wu, Mousong; Sholze, Marko

2017-04-01

We investigated the importance of soil moisture data on assimilation of a terrestrial biosphere model (BETHY) for a long time period from 2010 to 2015. Totally, 101 parameters related to carbon turnover, soil respiration, as well as soil texture were selected for optimization within a carbon cycle data assimilation system (CCDAS). Soil moisture data from Soil Moisture and Ocean Salinity (SMOS) product was derived for 10 sites representing different plant function types (PFTs) as well as different climate zones. Uncertainty of SMOS soil moisture data was also estimated using triple collocation analysis (TCA) method by comparing with ASCAT dataset and BETHY forward simulation results. Assimilation of soil moisture to the system improved soil moisture as well as net primary productivity(NPP) and net ecosystem productivity (NEP) when compared with soil moisture derived from in-situ measurements and fluxnet datasets. Parameter uncertainties were largely reduced relatively to prior values. Using SMOS soil moisture data for assimilation of a terrestrial biosphere model proved to be an efficient approach in reducing uncertainty in ecosystem fluxes simulation. It could be further used in regional an global assimilation work to constrain carbon dioxide concentration simulation by combining with other sources of measurements.

Post-closure biosphere assessment modelling: comparison of complex and more stylised approaches.

PubMed

Walke, Russell C; Kirchner, Gerald; Xu, Shulan; Dverstorp, Björn

2015-10-01

Geological disposal facilities are the preferred option for high-level radioactive waste, due to their potential to provide isolation from the surface environment (biosphere) on very long timescales. Assessments need to strike a balance between stylised models and more complex approaches that draw more extensively on site-specific information. This paper explores the relative merits of complex versus more stylised biosphere models in the context of a site-specific assessment. The more complex biosphere modelling approach was developed by the Swedish Nuclear Fuel and Waste Management Co (SKB) for the Formark candidate site for a spent nuclear fuel repository in Sweden. SKB's approach is built on a landscape development model, whereby radionuclide releases to distinct hydrological basins/sub-catchments (termed 'objects') are represented as they evolve through land rise and climate change. Each of seventeen of these objects is represented with more than 80 site specific parameters, with about 22 that are time-dependent and result in over 5000 input values per object. The more stylised biosphere models developed for this study represent releases to individual ecosystems without environmental change and include the most plausible transport processes. In the context of regulatory review of the landscape modelling approach adopted in the SR-Site assessment in Sweden, the more stylised representation has helped to build understanding in the more complex modelling approaches by providing bounding results, checking the reasonableness of the more complex modelling, highlighting uncertainties introduced through conceptual assumptions and helping to quantify the conservatisms involved. The more stylised biosphere models are also shown capable of reproducing the results of more complex approaches. A major recommendation is that biosphere assessments need to justify the degree of complexity in modelling approaches as well as simplifying and conservative assumptions. In light of the uncertainties concerning the biosphere on very long timescales, stylised biosphere models are shown to provide a useful point of reference in themselves and remain a valuable tool for nuclear waste disposal licencing procedures. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effective UV radiation from model calculations and measurements

NASA Technical Reports Server (NTRS)

Feister, Uwe; Grewe, Rolf

1994-01-01

Model calculations have been made to simulate the effect of atmospheric ozone and geographical as well as meteorological parameters on solar UV radiation reaching the ground. Total ozone values as measured by Dobson spectrophotometer and Brewer spectrometer as well as turbidity were used as input to the model calculation. The performance of the model was tested by spectroradiometric measurements of solar global UV radiation at Potsdam. There are small differences that can be explained by the uncertainty of the measurements, by the uncertainty of input data to the model and by the uncertainty of the radiative transfer algorithms of the model itself. Some effects of solar radiation to the biosphere and to air chemistry are discussed. Model calculations and spectroradiometric measurements can be used to study variations of the effective radiation in space in space time. The comparability of action spectra and their uncertainties are also addressed.

Fluidized muds: a novel setting for the generation of biosphere diversity through geologic time.

PubMed

Aller, J Y; Aller, R C; Kemp, P F; Chistoserdov, A Y; Madrid, V M

2010-06-01

Reworked and fluidized fine-grained deposits in energetic settings are a major modern-day feature of river deltas and estuaries. Similar environments were probably settings for microbial evolution on the early Earth. These sedimentary systems act as efficient biogeochemical reactors with high bacterial phylogenetic diversity and functional redundancy. They are temporally rather than spatially structured, with repeated cycling of redox conditions and successive stages of microbial metabolic processes. Intense reworking of the fluidized bed entrains bacteria from varied habitats providing new, diverse genetic materials to contribute to horizontal gene transfer events and the creation of new bacterial ecotypes. These vast mud environments may act as exporters and promoters of biosphere diversity and novel adaptations, potentially on a globally important scale.

Global Biology Research Program: Program plan

NASA Technical Reports Server (NTRS)

1983-01-01

Biological processes which play a dominant role in these cycles which transform and transfer much of this material throughout the biosphere are examined. A greater understanding of planetary biological processes as revealed by the interaction of the biota and the environment. The rationale, scope, research strategy, and research priorities of the global biology is presented.

A comparison between the example reference biosphere model ERB 2B and a process-based model: simulation of a natural release scenario.

PubMed

Almahayni, T

2014-12-01

The BIOMASS methodology was developed with the objective of constructing defensible assessment biospheres for assessing potential radiological impacts of radioactive waste repositories. To this end, a set of Example Reference Biospheres were developed to demonstrate the use of the methodology and to provide an international point of reference. In this paper, the performance of the Example Reference Biosphere model ERB 2B associated with the natural release scenario, discharge of contaminated groundwater to the surface environment, was evaluated by comparing its long-term projections of radionuclide dynamics and distribution in a soil-plant system to those of a process-based, transient advection-dispersion model (AD). The models were parametrised with data characteristic of a typical rainfed winter wheat crop grown on a sandy loam soil under temperate climate conditions. Three safety-relevant radionuclides, (99)Tc, (129)I and (237)Np with different degree of sorption were selected for the study. Although the models were driven by the same hydraulic (soil moisture content and water fluxes) and radiological (Kds) input data, their projections were remarkably different. On one hand, both models were able to capture short and long-term variation in activity concentration in the subsoil compartment. On the other hand, the Reference Biosphere model did not project any radionuclide accumulation in the topsoil and crop compartments. This behaviour would underestimate the radiological exposure under natural release scenarios. The results highlight the potential role deep roots play in soil-to-plant transfer under a natural release scenario where radionuclides are released into the subsoil. When considering the relative activity and root depth profiles within the soil column, much of the radioactivity was taken up into the crop from the subsoil compartment. Further improvements were suggested to address the limitations of the Reference Biosphere model presented in this paper. Copyright © 2014 Elsevier Ltd. All rights reserved.

Identification of sensitive parameters of a tropical forest in Southern Mexico to improve the understanding of C-band radar images

NASA Astrophysics Data System (ADS)

Monsivais-Huertero, A.; Jimenez-Escalona, J. C.; Ramos, J.; Zempoaltecatl-Ramirez, E.

2013-05-01

Forest areas cover the 32% of the Mexican territory. Due to their geographical location, Mexico presents heterogeneous climatic and topographic conditions. The country is divided into two different regions: an arid /semiarid zone (North) and a tropical/temperate zone (South). Due to the effects of climate change, Mexico has been affected in two ways. In the North, there has been a desertification of regions as result of the absence of rainfall and a low rate of soil moisture. On the other hand, in the South, there has been an increase in the intensity of rainfall causing serious flooding. Another effect is the excessive deforestation in Southern Mexico. The FAO has determined that Mexico could present one of the highest losses of forest areas mainly in temperate and subtropical ecosystems. The Biosphere Reserve of Calakmul is the protected area with the largest surface of tropical forest in Mexico. The Biosphere Reserve of Calakmul is located in the state of Campeche that the flora and fauna are being affected. The type of vegetation located in the reserve of Calakmul Biosphere is rainforest with high spatial density and highly heterogeneous due to multiple plant species and the impact of human activities in the area. The satellite remote sensing techniques becomes a very useful tool to monitor the area because a large area can be covered. To understand the radar images, the identification of sensitive parameters governing the radar signal is necessary. With the launch of the satellites Radarsat-2, ASAR-Envisat and ALOSPalSAR, significant progress has been done in the interpretation of satellite radar images. Directly applying physical models becomes a problem due to the large number of input parameters in the models, together with the difficulty in measuring these parameters in the field. The models developed so far have been applied and validated for homogeneous forests with low or average spatial density of trees. This is why it is recommended in a comprehensive validation of the models for heterogeneous forests with a high density of trees, such as Calakmul. This paper presents a methodology for identifying sensitive parameters governing the scenes backscatter vegetables reserve Calakmul Biosphere from a physical model.

Spatio-temporal variability of hydro-chemical characteristics of coastal waters of Gulf of Mannar Marine Biosphere Reserve (GoMMBR), South India

NASA Astrophysics Data System (ADS)

Kathiravan, K.; Natesan, Usha; Vishnunath, R.

2017-03-01

The intention of this study was to appraise the spatial and temporal variations in the physico-chemical parameters of coastal waters of Rameswaram Island, Gulf of Mannar Marine Biosphere Reserve, south India, using multivariate statistical techniques, such as cluster analysis, factor analysis and principal component analysis. Spatio-temporal variations among the physico-chemical parameters are observed in the coastal waters of Gulf of Mannar, especially during northeast and post monsoon seasons. It is inferred that the high loadings of pH, temperature, suspended particulate matter, salinity, dissolved oxygen, biochemical oxygen demand, chlorophyll a, nutrient species of nitrogen and phosphorus strongly determine the discrimination of coastal water quality. Results highlight the important role of monsoonal variations to determine the coastal water quality around Rameswaram Island.

Novel insights into methane cycling, lateral gene transfer, and the rare biosphere within carbonate chimneys of the Lost City Hydrothermal Field (Invited)

NASA Astrophysics Data System (ADS)

Brazelton, W. J.; Ludwig, K. A.; Schrenk, M. O.; Kelley, D. S.; Sogin, M. L.; Baross, J. A.

2010-12-01

The Lost City Hydrothermal Field, an ultramafic-hosted system located 15 km west of the Mid-Atlantic Ridge, has experienced at least 30,000 years of hydrothermal activity. Previous studies have shown that its carbonate chimneys form by mixing of ~90°C, pH 9-11 hydrothermal fluids and cold seawater. Flow of methane and hydrogen-rich hydrothermal fluids through the carbonate chimneys supports dense microbial biofilm communities. This presentation will describe recent studies using new techniques that have provided greater insight into the microbial ecology and biogeochemistry of Lost City chimneys. We have investigated the archaeal and bacterial communities of Lost City carbonate chimneys that vary in age between ~30 and ~1200 years, as determined by U-Th isotope systematics. Using next-generation pyrosequencing technology, we collected >200,000 sequences of the V6 region of 16S rRNA genes. This extremely deep sequencing effort enabled detection of very rare organisms as well as abundant organisms detected by previous studies. The taxonomic composition of the archaeal and bacterial communities clearly differed in chimneys of different ages, and many of the rare sequences in young chimneys were more abundant in older chimneys, indicating that members of the rare biosphere can become dominant members of the ecosystem when environmental conditions change. These results suggest that a long history of selection over many cycles of chimney growth has resulted in numerous closely related species at Lost City, each of which is pre-adapted to a particular set of re-occurring environmental conditions. In this model, the rare biosphere can be considered a repository for genes that are not currently advantageous but have been in the past and may be again in the future. Interestingly, metagenomic sequencing at Lost City has indicated the potential for frequent lateral gene transfer among organisms inhabiting the chimney biofilms. Specifically, the Lost City metagenomic dataset contains the highest proportion of genes encoding transposases (the enzymes required for lateral gene transfer) of any metagenome yet reported. Therefore, we intend to test the hypothesis that the rare biosphere can serve as a source of genes that can be laterally transferred to and benefit organisms of ecological importance. The metagenomic dataset also provides clues regarding the physiology of the dominant organisms. For example, bacterial genes associated with sulfide and sulfur oxidation are present. We have also detected archaeal genes associated with nitrogen fixation and conversion of acetate to methane. Laboratory incubation experiments have shown that anaerobic methane oxidation also occurs in Lost City chimney biofilms. We will present a conceptual model of biogeochemical reactions expected to occur in Lost City biofilms.

FORest canopy atmosphere transfer (FORCAsT) 1.0: a 1-D model of biosphere-atmosphere chemical exchange

NASA Astrophysics Data System (ADS)

Ashworth, K.; Chung, S. H.; Griffin, R. J.; Chen, J.; Forkel, R.; Bryan, A. M.; Steiner, A. L.

2015-07-01

Biosphere-atmosphere interactions play a critical role in governing atmospheric composition, mediating the concentration of key species such as ozone and aerosol, thereby influencing air quality and climate. The exchange of reactive trace gases and their oxidation products (both gas and particle phase) is of particular importance in this process. The FORCAsT (FORest Canopy AtmoSphere Transfer) one-dimensional model is developed to study the emission, deposition, chemistry and transport of volatile organic compounds (VOCs) and their oxidation products in the atmosphere within and above the forest canopy. We include an equilibrium partitioning scheme, making FORCAsT one of the few canopy models currently capable of simulating the formation of secondary organic aerosols (SOA) from VOC oxidation in a forest environment. We evaluate the capability of FORCAsT to reproduce observed concentrations of key gas-phase species and report modeled SOA concentrations within and above a mixed forest at the University of Michigan Biological Station (UMBS) during the Community Atmosphere-Biosphere Interactions Experiment (CABINEX) field campaign in summer 2009. We examine the impact of two different gas-phase chemical mechanisms on modelled concentrations of short-lived primary emissions, such as isoprene and monoterpenes, and their oxidation products. While the two chemistry schemes perform similarly under high-NOx conditions, they diverge at the low levels of NOx at UMBS. We identify peroxy radical and alkyl nitrate chemistry as the key causes of the differences, highlighting the importance of this chemistry in understanding the fate of biogenic VOCs (bVOCs) for both the modelling and measurement communities.

FORest Canopy Atmosphere Transfer (FORCAsT) 1.0: a 1-D model of biosphere-atmosphere chemical exchange

NASA Astrophysics Data System (ADS)

Ashworth, K.; Chung, S. H.; Griffin, R. J.; Chen, J.; Forkel, R.; Bryan, A. M.; Steiner, A. L.

2015-11-01

Biosphere-atmosphere interactions play a critical role in governing atmospheric composition, mediating the concentrations of key species such as ozone and aerosol, thereby influencing air quality and climate. The exchange of reactive trace gases and their oxidation products (both gas and particle phase) is of particular importance in this process. The FORCAsT (FORest Canopy Atmosphere Transfer) 1-D model is developed to study the emission, deposition, chemistry and transport of volatile organic compounds (VOCs) and their oxidation products in the atmosphere within and above the forest canopy. We include an equilibrium partitioning scheme, making FORCAsT one of the few canopy models currently capable of simulating the formation of secondary organic aerosols (SOAs) from VOC oxidation in a forest environment. We evaluate the capability of FORCAsT to reproduce observed concentrations of key gas-phase species and report modeled SOA concentrations within and above a mixed forest at the University of Michigan Biological Station (UMBS) during the Community Atmosphere-Biosphere Interactions Experiment (CABINEX) field campaign in the summer of 2009. We examine the impact of two different gas-phase chemical mechanisms on modelled concentrations of short-lived primary emissions, such as isoprene and monoterpenes, and their oxidation products. While the two chemistry schemes perform similarly under high-NOx conditions, they diverge at the low levels of NOx at UMBS. We identify peroxy radical and alkyl nitrate chemistry as the key causes of the differences, highlighting the importance of this chemistry in understanding the fate of biogenic VOCs (bVOCs) for both the modelling and measurement communities.

Is there a shadow biosphere of silicon utilizing organisms on earth?

NASA Astrophysics Data System (ADS)

Das, P.; Das, S.

2012-12-01

The idea of shadow biosphere was first visualized by Carol Cleland and Shelley Copley of the University of Colorado in 2005. Since that time many scientists were interested in this subject and the basis of this paper is also correlated with this novel idea. A shadow biosphere essentially consists of self replicating bodies utilizing one or more chemicals which are not exploited to such extent by organisms of the real biosphere. Silicon-utilizing organisms mainly belong to the diatoms, some other algae, sponges, monocotyledon plants in this category are classified by us. They can survive in extremes of temperature, pressure, radiation, pH, salinity and nutrient conditions and this unusual tolerance to stress depends on their silicon biomineralization occurring either as a biologically controlled process or as a biologically induced process. In the control process silicate is sequestered and transferred to the intracellular silica deposition vesicle by energy driven pump mechanism in presence of specific transporter protein. In induced silicon mineralization, initial amorphous nucleation of silicon is gradually transformed to a crystalline phase. Besides these two methods, there are also other processes in which formation of silanol and siloxane can occur from oligomers of silica originating from monomers by Hydrogen bonding, cation bridging and direct electrostatic interactions. The structure of the silica biomineralised cell wall in silicon utilizing organisms is very complex, but this may explain their ability to stress tolerance and their possible coordinating role with other essential bioactive elements in nature. When electropositive elements are less, then polymerization of silicon-oxygen excess may occur easily, particularly in carbon and nitrogen paucity in the environment. Thus all these features indicate possibility of a shadow biosphere of these organisms on earth.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Uhle, Maria

These funds were transferred from DOE to NSF as DOE's contribution to the U.S. Global Change Research Program in support of 4 internationalnactivities/programs as approved by the U.S. Global Change Research Program on 14 March 2014. The programs are the International Geosphere-Biosphere Programme, the DIVERSITAS programme, and the World Climate Research Program. All program awards ended as of 09-23-2015.

Applications of the U.S. Geological Survey's global land cover product

USGS Publications Warehouse

Reed, B.

1997-01-01

The U.S. Geological Survey (USGS), in partnership with several international agencies and universities, has produced a global land cover characteristics database. The land cover data were created using multitemporal analysis of advanced very high resolution radiometer satellite images in conjunction with other existing geographic data. A translation table permits the conversion of the land cover classes into several conventional land cover schemes that are used by ecosystem modelers, climate modelers, land management agencies, and other user groups. The alternative classification schemes include Global Ecosystems, the Biosphere Atmosphere Transfer Scheme, the Simple Biosphere, the USGS Anderson Level 2, and the International Geosphere Biosphere Programme. The distribution system for these data is through the World Wide Web (the web site address is: http://edcwww.cr.usgs.gov/landdaac/glcc/glcc.html) or by magnetic media upon special request The availability of the data over the World Wide Web, in conjunction with the flexible database structure, allows easy data access to a wide range of users. The web site contains a user registration form that allows analysis of the diverse applications of large-area land cover data. Currently, applications are divided among mapping (20 percent), conservation (30 percent), and modeling (35 percent).

The Possible Emergence of Life and Differentiation of a Shallow Biosphere on Irradiated Icy Worlds: The Example of Europa

NASA Astrophysics Data System (ADS)

Russell, Michael J.; Murray, Alison E.; Hand, Kevin P.

2017-12-01

Irradiated ice-covered ocean worlds with rocky mafic mantles may provide the conditions needed to drive the emergence and maintenance of life. Alkaline hydrothermal springs - relieving the geophysical, thermal, and chemical disequilibria between oceans and tidally stressed crusts - could generate inorganic barriers to the otherwise uncontrolled and kinetically disfavored oxidation of hydrothermal hydrogen and methane. Ionic gradients imposed across these inorganic barriers, comprising iron oxyhydroxides and sulfides, could drive the hydrogenation of carbon dioxide and the oxidation of methane through thermodynamically favorable metabolic pathways leading to early life-forms. In such chemostatic environments, fuels may eventually outweigh oxidants. Ice-covered oceans are primarily heated from below, creating convection that could transport putative microbial cells and cellular cooperatives upward to congregate beneath an ice shell, potentially giving rise to a highly focused shallow biosphere. It is here where electron acceptors, ultimately derived from the irradiated surface, could be delivered to such life-forms through exchange with the icy surface. Such zones would act as "electron disposal units" for the biosphere, and occupants might be transferred toward the surface by buoyant diapirs and even entrained into plumes.

Developing a global mixed-canopy, height-variable vegetation structure dataset for estimating global vegetation albedo and biomass in the NASA Ent Terrestrial Biosphere Model and GISS GCM

NASA Astrophysics Data System (ADS)

Montes, C.; Kiang, N. Y.; Yang, W.; Ni-Meister, W.; Schaaf, C.; Aleinov, I. D.; Jonas, J.; Zhao, F. A.; Yao, T.; Wang, Z.; Sun, Q.

2015-12-01

Processes determining biosphere-atmosphere coupling are strongly influenced by vegetation structure. Thus, ecosystem carbon sequestration and evapotranspiration affecting global carbon and water balances will depend upon the spatial extent of vegetation, its vertical structure, and its physiological variability. To represent this globally, Dynamic Global Vegetation Models (DGVMs) coupled to General Circulation Models (GCMs) make use of satellite and/or model-based vegetation classifications often composed by homogeneous communities. This work aims at developing a new Global Vegetation Structure Dataset (GVSD) by incorporating varying vegetation heights for mixed plant communities to be used as input to the Ent Terrestrial Biosphere Model (TBM), the DGVM coupled to the NASA Goddard Institute for Space Studies (GISS) GCM. Information sources include the Moderate Resolution Imaging Spectroradiometer (MODIS) land cover and plant functional types (PFTs) (Friedl et al., 2010), vegetation height from the Geoscience Laser Altimeter System (GLAS) on board ICESat (Ice, Cloud, and land Elevation Satellite) (Simard et al., 2011; Tang et al., 2014) along with the Global Data Sets of Vegetation Leaf Area Index (LAI)3g (Zhu et al. 2013). Further PFT partitioning is performed according to a climate classification utilizing the Climate Research Unit (CRU) and the NOAA Global Precipitation Climatology Centre (GPCC) data. Final products are a GVSD consisting of mixed plant communities (e.g. mixed forests, savannas, mixed PFTs) following the Ecosystem Demography model (Moorcroft et al., 2001) approach represented by multi-cohort community patches at the sub-grid level of the GCM, which are ensembles of identical individuals whose differences are represented by PFTs, canopy height, density and vegetation structure sensitivity to allometric parameters. To assess the sensitivity of the GISS GCM to vegetation structure, we produce a range of estimates of Ent TBM biomass and plant densities by varying allometric specifications. Ultimately, this GVSD will serve as a template for community data sets, and be used as boundary conditions to the Ent TBM for prediction of canopy albedo in the Analytical Clumped Two-Stream canopy radiative transfer scheme, biomass, primary productivity, respiration, and GISS GCM climate.

Evolvability Is an Evolved Ability: The Coding Concept as the Arch-Unit of Natural Selection.

PubMed

Janković, Srdja; Ćirković, Milan M

2016-03-01

Physical processes that characterize living matter are qualitatively distinct in that they involve encoding and transfer of specific types of information. Such information plays an active part in the control of events that are ultimately linked to the capacity of the system to persist and multiply. This algorithmicity of life is a key prerequisite for its Darwinian evolution, driven by natural selection acting upon stochastically arising variations of the encoded information. The concept of evolvability attempts to define the total capacity of a system to evolve new encoded traits under appropriate conditions, i.e., the accessible section of total morphological space. Since this is dependent on previously evolved regulatory networks that govern information flow in the system, evolvability itself may be regarded as an evolved ability. The way information is physically written, read and modified in living cells (the "coding concept") has not changed substantially during the whole history of the Earth's biosphere. This biosphere, be it alone or one of many, is, accordingly, itself a product of natural selection, since the overall evolvability conferred by its coding concept (nucleic acids as information carriers with the "rulebook of meanings" provided by codons, as well as all the subsystems that regulate various conditional information-reading modes) certainly played a key role in enabling this biosphere to survive up to the present, through alterations of planetary conditions, including at least five catastrophic events linked to major mass extinctions. We submit that, whatever the actual prebiotic physical and chemical processes may have been on our home planet, or may, in principle, occur at some time and place in the Universe, a particular coding concept, with its respective potential to give rise to a biosphere, or class of biospheres, of a certain evolvability, may itself be regarded as a unit (indeed the arch-unit) of natural selection.

Engineering Challenges for Closed Ecological System facilities

NASA Astrophysics Data System (ADS)

Dempster, William; Nelson, Mark; Allen, John P.

2012-07-01

Engineering challenges for closed ecological systems include methods of achieving closure for structures of different materials, and developing methods of allowing energy (for heating and cooling) and information transfer through the materially closed structure. Methods of calculating degree of closure include measuring degradation rates of inert trace gases introduced into the system. An allied problem is developing means of locating where leaks are located so that they may be repaired and degree of closure maintained. Once closure is achieved, methods of dealing with the pressure differentials between inside and outside are needed: from inflatable structures which might adjust to the pressure difference to variable volume chambers attached to the life systems component. These issues are illustrated through the engineering employed at Biosphere 2, the Biosphere 2 Test Module and the Laboratory Biosphere and a discussion of methods used by other closed ecological system facility engineers. Ecological challenges include being able to handle faster cycling rates and accentuated daily and seasonal fluxes of critical life elements such as carbon dioxide, oxygen, water, macro- and mico-nutrients. The problems of achieving sustainability in closed systems for life support include how to handle atmospheric dynamics including trace gases, producing a complete human diet and recycling nutrients and maintaining soil fertility, healthy air and water and preventing the loss of crucial elements from active circulation. In biospheric facilities the challenge is also to produce analogue to natural biomes and ecosystems, studying processes of self-organization and adaptation in systems that allow specification or determination of state variables and cycles which may be followed through all interactions from atmosphere to soils.

Developing a global mixed-canopy, height-variable vegetation structure dataset for estimating global vegetation albedo by a clumped canopy radiative transfer scheme in the NASA Ent Terrestrial Biosphere Model and GISS GCM

NASA Astrophysics Data System (ADS)

Montes, Carlo; Kiang, Nancy Y.; Ni-Meister, Wenge; Yang, Wenze; Schaaf, Crystal; Aleinov, Igor; Jonas, Jeffrey A.; Zhao, Feng; Yao, Tian; Wang, Zhuosen; Sun, Qingsong; Carrer, Dominique

2016-04-01

Processes determining biosphere-atmosphere coupling are strongly influenced by vegetation structure. Thus, ecosystem carbon sequestration and evapotranspiration affecting global carbon and water balances will depend upon the spatial extent of vegetation, its vertical structure, and its physiological variability. To represent this globally, Dynamic Global Vegetation Models (DGVMs) coupled to General Circulation Models (GCMs) make use of satellite and/or model-based vegetation classifications often composed by homogeneous communities. This work aims at developing a new Global Vegetation Structure Dataset (GVSD) by incorporating varying vegetation heights for mixed plant communities to be used as boundary conditions to the Analytical Clumped Two-Stream (ACTS) canopy radiative transfer scheme (Ni-Meister et al., 2010) incorporated into the NASA Ent Terrestrial Biosphere Model (TBM), the DGVM coupled to the NASA Goddard Institute for Space Studies (GISS) GCM. Information sources about land surface and vegetation characteristics obtained from a number of earth observation platforms and algorithms include the Moderate Resolution Imaging Spectroradiometer (MODIS) land cover and plant functional types (PFTs) (Friedl et al., 2010), soil albedo derived from MODIS (Carrer et al., 2014), along with vegetation height from the Geoscience Laser Altimeter System (GLAS) on board ICESat (Ice, Cloud, and land Elevation Satellite) (Simard et al., 2011; Tang et al., 2014). Three widely used Leaf Area Index (LAI) products are compared as input to the GVSD and ACTS forcing in terms of vegetation albedo: Global Data Sets of Vegetation (LAI)3g (Zhu et al. 2013), Beijing Normal University LAI (Yuan et al., 2011), and MODIS MOD15A2H product (Yang et al., 2006). Further PFT partitioning is performed according to a climate classification utilizing the Climate Research Unit (CRU; Harris et al., 2013) and the NOAA Global Precipitation Climatology Centre (GPCC; Scheider et al., 2014) data. Final products are a GVSD consisting of mixed plant communities (e.g. mixed forests, savannas, mixed PFTs) following the Ecosystem Demography model (Moorcroft et al., 2001) approach represented by multi-cohort community patches at the sub-grid level of the GCM, which are ensembles of identical individuals whose differences are represented by PFTs, canopy height, density and vegetation structure sensitivity to allometric parameters. The performance of the Ent TBM in estimating VIS-NIR vegetation albedo by the new GVSD and ACTS is assessed first by comparison against the previous GISS GCM vegetation classification and prescribed Lambertian albedoes of Matthews (1984), and secondly, against MODIS global estimations and FLUXNET site-scale observations. Ultimately, this GVSD will serve as a template for community data sets, and be used as boundary conditions to the Ent TBM for prediction of biomass, carbon balances and GISS GCM climate.

Poroelastic Parameters of Peru Margin Sediments: Implications for Flow and Transport at Multiple Scales in the Marine Biosphere

NASA Astrophysics Data System (ADS)

Gettemy, G. L.; Cikoski, C.; Tobin, H. J.

2004-12-01

As part of a broader investigation of the deep marine subsurface environment, the first biosphere-focused drilling expedition, Leg 201, of the Ocean Drilling Program (ODP) occupied five unique sites in the Peru Margin (in a 1200 km2 region centered at 10 S, 80E). These sites represent the entire range of shallow biogeological conditions associated with this convergent margin:deep-water, mixed clay-pelagic sediments ocean-ward of the trench; slope-apron and prism toe sediments at the deformation front; and several distinct lithostratigraphic sequences on the continental shelf. Microbial enumeration and pore-water geochemistry results show that each particular site is both consistent and unique--consistent in terms of general biotic quantity and activity as predicted by energy flux and redox potential given the depositional environment and sedimentary record, but unique at key biogeological boundaries such as lithologic and/or physical property interfaces. This research addresses questions related to our understanding of how and why these boundaries form by looking at poroelastic and hydrologic parameters measured at multiple scales, from sub-millimeter to several centimeters. The issue of measurement scale, especially in regard to permeability and diffusivity characterization, is vital to interpreting observations of biologically-mediated diagenetic fronts (e.g., dolomitic lenses, depth- or time-varying barite fronts). These parameters are derived from (i) hydrologic and wave propagation experiments, (ii) SEM images, and (iii) shipboard split-core measurements, and structured in a modified Biot poroelasticity framework. This approach also allows quantification of the local heterogeneity of these parameters at the scale applicable to (and controlled by) microbial life; these results can then be used to formulate predictive models of the impact of biogeochemical processes. Ultimately, these models could then be used in interpretation of new remote-sensed data (e.g., from borehole tools, high-frequency backscatter devices), a fundamental challenge for all types of biospheric imaging everywhere.

The Possible Emergence of Life and Differentiation of a Shallow Biosphere on Irradiated Icy Worlds: The Example of Europa.

PubMed

Russell, Michael J; Murray, Alison E; Hand, Kevin P

2017-12-01

Irradiated ice-covered ocean worlds with rocky mafic mantles may provide the conditions needed to drive the emergence and maintenance of life. Alkaline hydrothermal springs-relieving the geophysical, thermal, and chemical disequilibria between oceans and tidally stressed crusts-could generate inorganic barriers to the otherwise uncontrolled and kinetically disfavored oxidation of hydrothermal hydrogen and methane. Ionic gradients imposed across these inorganic barriers, comprising iron oxyhydroxides and sulfides, could drive the hydrogenation of carbon dioxide and the oxidation of methane through thermodynamically favorable metabolic pathways leading to early life-forms. In such chemostatic environments, fuels may eventually outweigh oxidants. Ice-covered oceans are primarily heated from below, creating convection that could transport putative microbial cells and cellular cooperatives upward to congregate beneath an ice shell, potentially giving rise to a highly focused shallow biosphere. It is here where electron acceptors, ultimately derived from the irradiated surface, could be delivered to such life-forms through exchange with the icy surface. Such zones would act as "electron disposal units" for the biosphere, and occupants might be transferred toward the surface by buoyant diapirs and even entrained into plumes. Key Words: Biofilms-Europa-Extraterrestrial life-Hydrothermal systems. Astrobiology 17, 1265-1273.

The Possible Emergence of Life and Differentiation of a Shallow Biosphere on Irradiated Icy Worlds: The Example of Europa

PubMed Central

Murray, Alison E.; Hand, Kevin P.

2017-01-01

Abstract Irradiated ice-covered ocean worlds with rocky mafic mantles may provide the conditions needed to drive the emergence and maintenance of life. Alkaline hydrothermal springs—relieving the geophysical, thermal, and chemical disequilibria between oceans and tidally stressed crusts—could generate inorganic barriers to the otherwise uncontrolled and kinetically disfavored oxidation of hydrothermal hydrogen and methane. Ionic gradients imposed across these inorganic barriers, comprising iron oxyhydroxides and sulfides, could drive the hydrogenation of carbon dioxide and the oxidation of methane through thermodynamically favorable metabolic pathways leading to early life-forms. In such chemostatic environments, fuels may eventually outweigh oxidants. Ice-covered oceans are primarily heated from below, creating convection that could transport putative microbial cells and cellular cooperatives upward to congregate beneath an ice shell, potentially giving rise to a highly focused shallow biosphere. It is here where electron acceptors, ultimately derived from the irradiated surface, could be delivered to such life-forms through exchange with the icy surface. Such zones would act as “electron disposal units” for the biosphere, and occupants might be transferred toward the surface by buoyant diapirs and even entrained into plumes. Key Words: Biofilms—Europa—Extraterrestrial life—Hydrothermal systems. Astrobiology 17, 1265–1273. PMID:29016193

Natural Variation in the Carbon Oxidation State and Oxidative Ratio of a Deciduous Forest

NASA Astrophysics Data System (ADS)

Masiello, C. A.; Calligan, L. J.; Gallagher, M. E.; Hockaday, W. C.; Robertson, G. P.

2007-12-01

Here we report natural variability in the oxidative ratio (OR) and carbon oxidation state (Cox) of a temperate, deciduous forest measured on an annual basis via elemental analysis of leaf litter. The OR of the terrestrial biosphere is a key component in O2 -based calculations of the biosphere's uptake of fossil fuel CO2 (eg [ Keeling, et al., 1996]). Ecosystem OR has been assumed to be invariant; however, small OR variations may cause significant shifts in the calculated size of the terrestrial biospheric C sink [ Randerson, et al., 2006]. Accurate measurements of OR are necessary for the accurate apportionment of fossil fuel CO2 between the atmosphere, oceans, and terrestrial biosphere. Ecosystem OR is linearly related to Cox, a parameter which can be easily measured via elemental analysis, calorimetry, or solid state nuclear magnetic resonance [ Masiello, et al., 2007]. We are measuring Cox and OR at the three deciduous forest sites within the Kellogg Biological Station NSF LTER (lter.kbs.msu.edu). We report OR from litter collected from three forest sites from 1998-2003, a time series which covers periods of both normal and low precipitation. We also report error introduced in the Cox to OR conversion via a range of plausible assumptions about ecosystem N cycling. Keeling, R. F., et al. (1996), Global and hemispheric CO2 sinks deduced from changes in atmospheric O2 concentration, Nature, 381, 218-221. Masiello, C.A. et al. (in review 2007) Two new approaches for measuring ecosystem carbon oxidation state and oxidative ratio. J.G.R. Biogeosciences. Randerson, J. T., et al. (2006), Is carbon within the global terrestrial biosphere becoming more oxidized? Implications for trends in atmospheric O2, Global Change Biology, 12, 260-271.

Predicting ecosystem dynamics at regional scales: an evaluation of a terrestrial biosphere model for the forests of northeastern North America.

PubMed

Medvigy, David; Moorcroft, Paul R

2012-01-19

Terrestrial biosphere models are important tools for diagnosing both the current state of the terrestrial carbon cycle and forecasting terrestrial ecosystem responses to global change. While there are a number of ongoing assessments of the short-term predictive capabilities of terrestrial biosphere models using flux-tower measurements, to date there have been relatively few assessments of their ability to predict longer term, decadal-scale biomass dynamics. Here, we present the results of a regional-scale evaluation of the Ecosystem Demography version 2 (ED2)-structured terrestrial biosphere model, evaluating the model's predictions against forest inventory measurements for the northeast USA and Quebec from 1985 to 1995. Simulations were conducted using a default parametrization, which used parameter values from the literature, and a constrained model parametrization, which had been developed by constraining the model's predictions against 2 years of measurements from a single site, Harvard Forest (42.5° N, 72.1° W). The analysis shows that the constrained model parametrization offered marked improvements over the default model formulation, capturing large-scale variation in patterns of biomass dynamics despite marked differences in climate forcing, land-use history and species-composition across the region. These results imply that data-constrained parametrizations of structured biosphere models such as ED2 can be successfully used for regional-scale ecosystem prediction and forecasting. We also assess the model's ability to capture sub-grid scale heterogeneity in the dynamics of biomass growth and mortality of different sizes and types of trees, and then discuss the implications of these analyses for further reducing the remaining biases in the model's predictions.

Frozen soil parameterization in a distributed biosphere hydrological model

NASA Astrophysics Data System (ADS)

Wang, L.; Koike, T.; Yang, K.; Jin, R.; Li, H.

2010-03-01

In this study, a frozen soil parameterization has been modified and incorporated into a distributed biosphere hydrological model (WEB-DHM). The WEB-DHM with the frozen scheme was then rigorously evaluated in a small cold area, the Binngou watershed, against the in-situ observations from the WATER (Watershed Allied Telemetry Experimental Research). First, by using the original WEB-DHM without the frozen scheme, the land surface parameters and two van Genuchten parameters were optimized using the observed surface radiation fluxes and the soil moistures at upper layers (5, 10 and 20 cm depths) at the DY station in July. Second, by using the WEB-DHM with the frozen scheme, two frozen soil parameters were calibrated using the observed soil temperature at 5 cm depth at the DY station from 21 November 2007 to 20 April 2008; while the other soil hydraulic parameters were optimized by the calibration of the discharges at the basin outlet in July and August that covers the annual largest flood peak in 2008. With these calibrated parameters, the WEB-DHM with the frozen scheme was then used for a yearlong validation from 21 November 2007 to 20 November 2008. Results showed that the WEB-DHM with the frozen scheme has given much better performance than the WEB-DHM without the frozen scheme, in the simulations of soil moisture profile at the cold regions catchment and the discharges at the basin outlet in the yearlong simulation.

Achieving Closure for Bioregenerative Life Support Systems: Engineering and Ecological Challenges, Research Opportunities

NASA Astrophysics Data System (ADS)

Dempster, William; Allen, John P.

Closed systems are desirable for a number of purposes: space life support systems where precious life-supporting resources need to be kept inside; biospheric systems; where global ecological pro-cesses can be studied in great detail and testbeds where research topics requiring isolation from the outside (e.g. genetically modified organisms; radioisotopes) can be studied in isolation from the outside environment and where their ecological interactions and fluxes can be studied. But to achieve and maintain closure raises both engineering and ecological challenges. Engineering challenges include methods of achieving closure for structures of different materials, and devel-oping methods of allowing energy (for heating and cooling) and information transfer through the materially closed structure. Methods of calculating degree of closure include measuring degradation rates of inert trace gases introduced into the system. An allied problem is devel-oping means of locating where leaks are located so that they may be repaired and degree of closure maintained. Once closure is achieved, methods of dealing with the pressure differen-tials between inside and outside are needed: from inflatable structures which might adjust to the pressure difference to variable volume chambers attached to the life systems component. These issues are illustrated through the engineering employed at Biosphere 2, the Biosphere 2 Test Module and the Laboratory Biosphere and a discussion of methods used by other closed ecological system facility engineers. Ecological challenges include being able to handle faster cycling rates and accentuated daily and seasonal fluxes of critical life elements such as carbon dioxide, oxygen, water, macro-and mico-nutrients. The problems of achieving sustainability in closed systems for life support include how to handle atmospheric dynamics including trace gases, producing a complete human diet and recycling nutrients and maintaining soil fertility, healthy air and water and preventing the loss of crucial elements from active circulation. In biospheric facilities the challenge is also to produce analogue to natural biomes and ecosys-tems, studying processes of self-organization and adaptation in systems that allow specification or determination of state variables and cycles which may be followed through all interactions from atmosphere to soils.

Multi-model analysis of terrestrial carbon cycles in Japan: limitations and implications of model calibration using eddy flux observations

NASA Astrophysics Data System (ADS)

Ichii, K.; Suzuki, T.; Kato, T.; Ito, A.; Hajima, T.; Ueyama, M.; Sasai, T.; Hirata, R.; Saigusa, N.; Ohtani, Y.; Takagi, K.

2010-07-01

Terrestrial biosphere models show large differences when simulating carbon and water cycles, and reducing these differences is a priority for developing more accurate estimates of the condition of terrestrial ecosystems and future climate change. To reduce uncertainties and improve the understanding of their carbon budgets, we investigated the utility of the eddy flux datasets to improve model simulations and reduce variabilities among multi-model outputs of terrestrial biosphere models in Japan. Using 9 terrestrial biosphere models (Support Vector Machine - based regressions, TOPS, CASA, VISIT, Biome-BGC, DAYCENT, SEIB, LPJ, and TRIFFID), we conducted two simulations: (1) point simulations at four eddy flux sites in Japan and (2) spatial simulations for Japan with a default model (based on original settings) and a modified model (based on model parameter tuning using eddy flux data). Generally, models using default model settings showed large deviations in model outputs from observation with large model-by-model variability. However, after we calibrated the model parameters using eddy flux data (GPP, RE and NEP), most models successfully simulated seasonal variations in the carbon cycle, with less variability among models. We also found that interannual variations in the carbon cycle are mostly consistent among models and observations. Spatial analysis also showed a large reduction in the variability among model outputs. This study demonstrated that careful validation and calibration of models with available eddy flux data reduced model-by-model differences. Yet, site history, analysis of model structure changes, and more objective procedure of model calibration should be included in the further analysis.

Biospheric-atmospheric coupling on the early Earth

NASA Technical Reports Server (NTRS)

Levine, J. S.

1991-01-01

Theoretical calculations performed with a one-dimensional photochemical model have been performed to assess the biospheric-atmospheric transfer of gases. Ozone reached levels to shield the Earth from biologically lethal solar ultraviolet radiation (220-300 nm) when atmospheric oxygen reached about 1/10 of its present atmospheric level. In the present atmosphere, about 90 percent of atmospheric nitrous oxide is destroyed via solar photolysis in the stratosphere with about 10 percent destroyed via reaction with excited oxygen atoms. The reaction between nitrous oxide and excited oxygen atoms leads to the production of nitric oxide in the stratosphere, which is responsible for about 70 percent of the global destruction of oxygen in the stratosphere. In the oxygen/ozone deficient atmosphere, solar photolysis destroyed about 100 percent of the atmospheric nitrous oxide, relegating the production of nitric oxide via reaction with excited oxygen to zero. Our laboratory and field measurements indicate that atmospheric oxygen promotes the biogenic production of N2O and NO via denitrification and the biogenic production of methane by methanogenesis.

Initial experimental results from the Laboratory Biosphere closed ecological system facility

NASA Astrophysics Data System (ADS)

Alling, A.; Allen, J.; Dempster, W.; Nelson, M.; Silverstone, S.; van Thillo, M.

Results from the closure and initial closed ecological system research in the "Laboratory Biosphere" facility in Santa Fe, New Mexico (USA) will be presented. The facility was initially sealed in April 2002; and the first crop experiments with soybeans commenced in May 2002. The Laboratory Biosphere was created by the team which invented, built and operated Biosphere 2 during its years of closed ecological system functioning (1991-94) and is a testbed to build upon the lessons learned. It is an opportunity to continue experiments with a sustainable soil based agriculture system unlike most bioregenerative systems which use hydroponic systems dependent on a supply of nutrient solution. Because of the small volume of the system (34-45 m3), developing mechanisms to keep parameters like carbon dioxide within acceptable limits will be critical. Recycle of nutrients within the system to maintain soil fertility; and the ability of the inherent complex ecology of soils and a soil bed reactor to handle trace gas buildups are primary research goals. Other research goals are determination of short and long-term exchanges between soil, plants and atmosphere, especially for carbon dioxide, oxygen, nitrogen, NOX, and methane, impact of cultivation (tillage) on soil/atmospheric exchanges., investigation and development of strategies to return nutrients to the soil to maintain fertility, e.g. shredding biomass vs. composting, impact on soil chemistry of returning leachate water to the soil as irrigation water. The microbiological status of soils prior to experiments and over time will allow measurement of changes in microbial diversity and the determination of the role of soil microbes in biogeochemical cycles. Integration of automated sensor and control in the system with real-time modeling has importance for operation, research and educational outreach programs. The Laboratory Biosphere is intended to test and develop a "cybersphere" (network of shared intelligence) that may be scaled up for natural ecosystems and the global environment.

Combined effects of climate and land management on watershed vegetation dynamics in an arid environment

Treesearch

Peilong Liu; Lu Hao; Cen Pan; Decheng Zhou; Yongqiang Liu; Ge Sun

2017-01-01

Leaf area index (LAI) is a key parameter to characterize vegetation dynamics and ecosystemstructure that determines the ecosystem functions and services such as cleanwater supply and carbon sequestration in awatershed. However, linking LAI dynamics and environmental controls (i.e., coupling biosphere, atmosphere, and anthroposphere) remains challenging and such type of...

Carbon isotope discrimination of arctic and boreal biomes inferred from remote atmospheric measurements and a biosphere-atmosphere model

NASA Astrophysics Data System (ADS)

Randerson, J. T.; Still, C. J.; Ballé, J. J.; Fung, I. Y.; Doney, S. C.; Tans, P. P.; Conway, T. J.; White, J. W. C.; Vaughn, B.; Suits, N.; Denning, A. S.

2002-07-01

Estimating discrimination against 13C during photosynthesis at landscape, regional, and biome scales is difficult because of large-scale variability in plant stress, vegetation composition, and photosynthetic pathway. Here we present estimates of 13C discrimination for northern biomes based on a biosphere-atmosphere model and on National Oceanic and Atmospheric Administration Climate Monitoring and Diagnostics Laboratory and Institute of Arctic and Alpine Research remote flask measurements. With our inversion approach, we solved for three ecophysiological parameters of the northern biosphere (13C discrimination, a net primary production light use efficiency, and a temperature sensitivity of heterotrophic respiration (a Q10 factor)) that provided a best fit between modeled and observed δ13C and CO2. In our analysis we attempted to explicitly correct for fossil fuel emissions, remote C4 ecosystem fluxes, ocean exchange, and isotopic disequilibria of terrestrial heterotrophic respiration caused by the Suess effect. We obtained a photosynthetic discrimination for arctic and boreal biomes between 19.0 and 19.6‰. Our inversion analysis suggests that Q10 and light use efficiency values that minimize the cost function covary. The optimal light use efficiency was 0.47 gC MJ-1 photosynthetically active radiation, and the optimal Q10 value was 1.52. Fossil fuel and ocean exchange contributed proportionally more to month-to-month changes in the atmospheric growth rate of δ13C and CO2 during winter months, suggesting that remote atmospheric observations during the summer may yield more precise estimates of the isotopic composition of the biosphere.

Origins of species: acquired genomes and individuality

NASA Technical Reports Server (NTRS)

Margulis, L.

1993-01-01

Entire genomes with their accompanying protein synthetic systems are transferred throughout the biosphere primarily as bacteria and protists which become symbionts as they irreversibly integrate into pre-existing organisms to form more complex individuals. Individualization is stabilized by simultaneous transmission of once-separate heterologous genetic systems. The origin of new species is hypothesized to correlate with the acquisition, integration and subsequent inheritance of such acquired microbial genomes. These processes were recognized by Mereschkovsky ("Symbiogenesis" in Russian, 1909) and by Wallin ("Symbionticism", see p. 181, this issue).

Planetary Bootstrap: A Prelude to Biosphere Phenomenology

NASA Astrophysics Data System (ADS)

Kazansky, Alexander B.

2004-08-01

This paper deals with systemic status as well as with some phenomenological and evolutionary aspects of biosphere. Biosphere is represented as multilevel autopoietic system in which different organizational levels are nested into each other. The conceptual model of punctuated epigenesis, biosphere evolutionary process is suggested, in which endogenous planetary organizational crises play role of evolutionary mechanism, creating novelty. The hypothesis is proposed, that the biosphere reaction on the humankind destructive activity reminds the distributed immune response of biological organism, described by F.Varela in his "cognitive immunology". The biosphere evolution is interpreted as the hermeneutical spiral of "Process Being" self-uncovering thus illustrating the historical process of transformation of biosphere as the type of Being in the periods of crises. Some arguments are adduced in favor of biosphere phenomenology development and application of the methods of second-order cybernetics to actual problems of planetary scale.

Quality assessment of pollution indicators in marine water at critical locations of the Gulf of Mannar Biosphere Reserve, Tuticorin.

PubMed

Rajendran, Viji; Nirmaladevi D, Shrinithivihahshini; Srinivasan, Balakrishnan; Rengaraj, Chithradevi; Mariyaselvam, Sheelamary

2018-01-01

The present study focused on the shoreline environment of urban and industrial areas, and the aim of this study was to assess the coastal water quality in the Gulf of Mannar Biosphere Reserve. Water samples were collected from five different coastal sites during the premonsoon and monsoon seasons. The samples were analyzed following the standard methods. The results showed that the levels of microbiological indicators in the samples highly exceeded the regional and national standard seawater permissible limits, and environmental parameters such as the total suspended solid and dissolved oxygen were affected significantly (p<0.05). To identify frequent pollution indicators, their levels should be estimated to determine possible pollution in coastal ecosystems due to human interventions. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Simplified Biosphere Model for Global Climate Studies.

NASA Astrophysics Data System (ADS)

Xue, Y.; Sellers, P. J.; Kinter, J. L.; Shukla, J.

1991-03-01

The Simple Biosphere Model (SiB) as described in Sellers et al. is a bio-physically based model of land surface-atmosphere interaction. For some general circulation model (GCM) climate studies, further simplifications are desirable to have greater computation efficiency, and more important, to consolidate the parametric representation. Three major reductions in the complexity of SiB have been achieved in the present study.The diurnal variation of surface albedo is computed in SiB by means of a comprehensive yet complex calculation. Since the diurnal cycle is quite regular for each vegetation type, this calculation can be simplified considerably. The effect of root zone soil moisture on stomatal resistance is substantial, but the computation in SiB is complicated and expensive. We have developed approximations, which simulate the effects of reduced soil moisture more simply, keeping the essence of the biophysical concepts used in SiB.The surface stress and the fluxes of heat and moisture between the top of the vegetation canopy and an atmospheric reference level have been parameterized in an off-line version of SiB based upon the studies by Businger et al. and Paulson. We have developed a linear relationship between Richardson number and aero-dynamic resistance. Finally, the second vegetation layer of the original model does not appear explicitly after simplification. Compared to the model of Sellers et al., we have reduced the number of input parameters from 44 to 21. A comparison of results using the reduced parameter biosphere with those from the original formulation in a GCM and a zero-dimensional model shows the simplified version to reproduce the original results quite closely. After simplification, the computational requirement of SiB was reduced by about 55%.

Biological effects of α-radiation exposure by (241)Am in Arabidopsis thaliana seedlings are determined both by dose rate and (241)Am distribution.

PubMed

Biermans, Geert; Horemans, Nele; Vanhoudt, Nathalie; Vandenhove, Hildegarde; Saenen, Eline; Van Hees, May; Wannijn, Jean; Vangronsveld, Jaco; Cuypers, Ann

2015-11-01

Human activity has led to an increasing amount of radionuclides in the environment and subsequently to an increased risk of exposure of the biosphere to ionising radiation. Due to their high linear energy transfer, α-emitters form a threat to biota when absorbed or integrated in living tissue. Among these, (241)Am is of major concern due to high affinity for organic matter and high specific activity. This study examines the dose-dependent biological effects of α-radiation delivered by (241)Am at the morphological, physiological and molecular level in 14-day old seedlings of Arabidopsis thaliana after hydroponic exposure for 4 or 7 days. Our results show that (241)Am has high transfer to the roots but low translocation to the shoots. In the roots, we observed a transcriptional response of reactive oxygen species scavenging and DNA repair pathways. At the physiological and morphological level this resulted in a response which evolved from redox balance control and stable biomass at low dose rates to growth reduction, reduced transfer and redox balance decline at higher dose rates. This situation was also reflected in the shoots where, despite the absence of a transcriptional response, the control of photosynthesis performance and redox balance declined with increasing dose rate. The data further suggest that the effects in both organs were initiated in the roots, where the highest dose rates occurred, ultimately affecting photosynthesis performance and carbon assimilation. Though further detailed study of nutrient balance and (241)Am localisation is necessary, it is clear that radionuclide uptake and distribution is a major parameter in the global exposure effects on plant performance and health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mineral Bionization - Surface Chemical Modeling of the Emergence of Life

NASA Astrophysics Data System (ADS)

Arrhenius, G.

2001-12-01

The earliest stages in entering an RNA-world require natural mechanisms that are capable of selective concentration of simple aldehydes from dilute solution in the environment (4), furthermore phosphorylation of the sequestered aldehydes (2) and their catalytic condensation to form, selectively, tetrose- (threose) or pentose- (ribose) phosphate (3); the latter representing the R in RNA. A variety of common positively charged sheet structure minerals (mixed valence double layer metal hydroxide minerals such as hydrotalcite and green rust) have proven to be remarkably capable of performing these crucial tasks under simplified natural conditions (1). These prebiotic model reactions have demonstrated plausible closure of the gap, previously thought to preclude the natural formation of nucleoside phosphates, the backbone components of the information carrying genetic material. Pioneering research by other workers (5) has demonstrated the feasibility of necessary further steps in the chain toward functional RNA; mineral (montmorillonite) catalyzed oligomerization of nucleotides, the formation of complementary RNA strands (6) and the enzymatic activity of RNA (ribozymes). These contributions have placed the initially conjectural concept of an initial RNA-world on an experimental footing. Remaining problems include the initial transfer of information to spontaneously forming RNA, sufficient to convey biofunctionallity (7). Also in this central problem mineral surface interactions may be speculated to play a natural role; a question that is open to experimental verification. References. 1. Pitsch, S.; Eschenmoser, A.; Gedulin, B.; Hui, S. and Arrhenius, G. Origins Life Evol. Biosphere, 1994, 24 (5), 389. 2. Kolb, V.; Zhang, S.; Xu, Y.; Arrhenius, G. Origins Life Evol. Biosphere, 1997, 27, 485. 3. Krishnamurthy, R.; Pitsch, S.; Arrhenius, G. Origins Life Evol. Biosphere, Origins Life Evol. Biosphere 1999, 29, 139 4. Pitsch, S.; Krishnamurthy, R.; Arrhenius, G. Helv. Chim. Acta. 2000, 83, 2398. 5. Ferris, J. P.; Ertem, G. J. J. Am. Chem. Soc. 1993, 115, 1270. 6. Orgel ,L.E. J. Theoretical Biol. 1986, 123, 127-149 7. Arrhenius, G; Life out of Chaos. In Palyi et al. eds. Fundamentals of Life, Elsevier, Paris, 2001

Development of a global land cover characteristics database and IGBP DISCover from 1 km AVHRR data

USGS Publications Warehouse

Loveland, Thomas R.; Reed, B.C.; Brown, Jesslyn F.; Ohlen, D.O.; Zhu, Z.; Yang, L.; Merchant, J.W.

2000-01-01

Researchers from the U.S. Geological Survey, University of Nebraska-Lincoln and the European Commission's Joint Research Centre, Ispra, Italy produced a 1 km resolution global land cover characteristics database for use in a wide range of continental-to global-scale environmental studies. This database provides a unique view of the broad patterns of the biogeographical and ecoclimatic diversity of the global land surface, and presents a detailed interpretation of the extent of human development. The project was carried out as an International Geosphere-Biosphere Programme, Data and Information Systems (IGBP-DIS) initiative. The IGBP DISCover global land cover product is an integral component of the global land cover database. DISCover includes 17 general land cover classes defined to meet the needs of IGBP core science projects. A formal accuracy assessment of the DISCover data layer will be completed in 1998. The 1 km global land cover database was developed through a continent-by-continent unsupervised classification of 1 km monthly Advanced Very High Resolution Radiometer (AVHRR) Normalized Difference Vegetation Index (NDVI) composites covering 1992-1993. Extensive post-classification stratification was necessary to resolve spectral/temporal confusion between disparate land cover types. The complete global database consists of 961 seasonal land cover regions that capture patterns of land cover, seasonality and relative primary productivity. The seasonal land cover regions were aggregated to produce seven separate land cover data sets used for global environmental modelling and assessment. The data sets include IGBP DISCover, U.S. Geological Survey Anderson System, Simple Biosphere Model, Simple Biosphere Model 2, Biosphere-Atmosphere Transfer Scheme, Olson Ecosystems and Running Global Remote Sensing Land Cover. The database also includes all digital sources that were used in the classification. The complete database can be sourced from the website: http://edcwww.cr.usgs.gov/landdaac/glcc/glcc.html.

Global Carbon Reservoir Oxidative Ratios

NASA Astrophysics Data System (ADS)

Masiello, C. A.; Gallagher, M. E.; Hockaday, W. C.

2010-12-01

Photosynthesis and respiration move carbon and oxygen between the atmosphere and the biosphere at a ratio that is characteristic of the biogeochemical processes involved. This ratio is called the oxidative ratio (OR) of photosynthesis and respiration, and is defined as the ratio of moles of O2 per moles of CO2. This O2/CO2 ratio is a characteristic of biosphere-atmosphere gas fluxes, much like the 13C signature of CO2 transferred between the biosphere and the atmosphere has a characteristic signature. OR values vary on a scale of 0 (CO2) to 2 (CH4), with most ecosystem values clustered between 0.9 and 1.2. Just as 13C can be measured for both carbon fluxes and carbon pools, OR can also be measured for fluxes and pools and can provide information about the processes involved in carbon and oxygen cycling. OR values also provide information about reservoir organic geochemistry because pool OR values are proportional to the oxidation state of carbon (Cox) in the reservoir. OR may prove to be a particularly valuable biogeochemical tracer because of its ability to couple information about ecosystem gas fluxes with ecosystem organic geochemistry. We have developed 3 methods to measure the OR of ecosystem carbon reservoirs and intercalibrated them to assure that they yield accurate, intercomparable data. Using these tools we have built a large enough database of biomass and soil OR values that it is now possible to consider the implications of global patterns in ecosystem OR values. Here we present a map of the natural range in ecosystem OR values and begin to consider its implications. One striking pattern is an apparent offset between soil and biospheric OR values: soil OR values are frequently higher than that of their source biomass. We discuss this trend in the context of soil organic geochemistry and gas fluxes.

Understanding Microbial Contributions to Planetary Atmosphere

NASA Technical Reports Server (NTRS)

DesMarais, David J.

2000-01-01

Should our search of distant, extrasolar planetary atmospheres encounter evidence of life, that evidence will most likely be the gaseous products of microorganisms. Our biosphere was exclusively microbial for over 80 percent of its history and, even today, microbes strongly influence atmospheric composition. Life's greatest environmental impact arises from its capacity for harvesting energy and creating organic matter. Microorganisms catalyze the equilibration of C, S and transition metal species at temperatures where such reactions can be very slow in the absence of life. Sunlight has been harvested through photosynthesis to create enormous energy reservoirs that exist in the form of coexisting reservoirs of reduced, organic C and S stored in Earth's crust, and highly oxidized species (oxygen, sulfate and ferric iron) stored in the crust, oceans and atmosphere. Our civilization taps that storehouse of energy by burning fossil fuels. As astrobiologists, we identify the chemical consequences of distant biospheres as expressed in the atmospheres of their planets. Our approach must recognize that planets, biospheres and atmospheres evolve and change. For example, a tectonically more active early Earth hosted a thermophilic, non-photosynthetic biosphere and a mildly reducing, carbon dioxide-rich and oxygen-poor atmosphere. Microorganisms acquired energy by consuming hydrogen and sulfide and producing a broad array of reduced C and S gases, most notably, methane. Later, diverse types of bacterial photosynthesis developed that enhanced productivity but were incapable of splitting water to produce oxygen. Later, but still prior to 2.6 billion years ago, oxygenic photosynthesis developed. We can expect to encounter distant biospheres that represent various stages of evolution and that coexist with atmospheres ranging from mildly reducing to oxidizing compositions. Accordinaly, we must be prepared to interpret a broad range of atmospheric compositions, all containing signatures of life. Remarkably little is known about the composition of our own earlier atmosphere, particularly prior to the rise of oxygen levels some 2.0 to 2.2 billion years ago. Thus, field and laboratory observations and theoretical simulations should be conducted to examine the relationships between the structure and function of microbial ecosystems and their gaseous products. Ecosystems that are analogs of our ancient biosphere (e.g., based upon chemosynthesis or non-oxygenic photosynthesis, thermophilic and subsurface communities, etc.) should be included. Because key environmental parameters such as temperature and levels of hydrogen, carbon dioxide and oxygen varied during planetary evolution, their consequences for microbial ecosystems should be explored.

Assessment of Food Chain Pathway Parameters in Biosphere Models: Annual Progress Report for Fiscal Year 2004

DOE Office of Scientific and Technical Information (OSTI.GOV)

Napier, Bruce A.; Krupka, Kenneth M.; Fellows, Robert J.

2004-12-02

This Annual Progress Report describes the work performed and summarizes some of the key observations to date on the U.S. Nuclear Regulatory Commission’s project Assessment of Food Chain Pathway Parameters in Biosphere Models, which was established to assess and evaluate a number of key parameters used in the food-chain models used in performance assessments of radioactive waste disposal facilities. Section 2 of this report describes activities undertaken to collect samples of soils from three regions of the United States, the Southeast, Northwest, and Southwest, and perform analyses to characterize their physical and chemical properties. Section 3 summarizes information gathered regardingmore » agricultural practices and common and unusual crops grown in each of these three areas. Section 4 describes progress in studying radionuclide uptake in several representative crops from the three soil types in controlled laboratory conditions. Section 5 describes a range of international coordination activities undertaken by Project staff in order to support the underlying data needs of the Project. Section 6 provides a very brief summary of the status of the GENII Version 2 computer program, which is a “client” of the types of data being generated by the Project, and for which the Project will be providing training to the US NRC staff in the coming Fiscal Year. Several appendices provide additional supporting information.« less

Frozen soil parameterization in a distributed biosphere hydrological model

NASA Astrophysics Data System (ADS)

Wang, L.; Koike, T.; Yang, K.; Jin, R.; Li, H.

2009-11-01

In this study, a frozen soil parameterization has been modified and incorporated into a distributed biosphere hydrological model (WEB-DHM). The WEB-DHM with the frozen scheme was then rigorously evaluated in a small cold area, the Binngou watershed, against the in-situ observations from the WATER (Watershed Allied Telemetry Experimental Research). In the summer 2008, land surface parameters were optimized using the observed surface radiation fluxes and the soil temperature profile at the Dadongshu-Yakou (DY) station in July; and then soil hydraulic parameters were obtained by the calibration of the July soil moisture profile at the DY station and by the calibration of the discharges at the basin outlet in July and August that covers the annual largest flood peak of 2008. The calibrated WEB-DHM with the frozen scheme was then used for a yearlong simulation from 21 November 2007 to 20 November 2008, to check its performance in cold seasons. Results showed that the WEB-DHM with the frozen scheme has given much better performance than the WEB-DHM without the frozen scheme, in the simulations of soil moisture profile at the DY station and the discharges at the basin outlet in the yearlong simulation.

Identifying and closing gaps in environmental monitoring by means of metadata, ecological regionalization and geostatistics using the UNESCO biosphere reserve Rhoen (Germany) as an example.

PubMed

Schröder, Winfried; Pesch, Roland; Schmidt, Gunther

2006-03-01

In Germany, environmental monitoring is intended to provide a holistic view of the environmental condition. To this end the monitoring operated by the federal states must use harmonized, resp., standardized methods. In addition, the monitoring sites should cover the ecoregions without any geographical gaps, the monitoring design should have no gaps in terms of ecologically relevant measurement parameters, and the sample data should be spatially without any gaps. This article outlines the extent to which the Rhoen Biosphere Reserve, occupying a part of the German federal states of Bavaria, Hesse and Thuringia, fulfills the listed requirements. The investigation considered collection, data banking and analysis of monitoring data and metadata, ecological regionalization and geostatistics. Metadata on the monitoring networks were collected by questionnaires and provided a complete inventory and description of the monitoring activities in the reserve and its surroundings. The analysis of these metadata reveals that most of the monitoring methods are harmonized across the boundaries of the three federal states the Rhoen is part of. The monitoring networks that measure precipitation, surface water levels, and groundwater quality are particularly overrepresented in the central ecoregions of the biosphere reserve. Soil monitoring sites are more equally distributed within the ecoregions of the Rhoen. The number of sites for the monitoring of air pollutants is not sufficient to draw spatially valid conclusions. To fill these spatial gaps, additional data on the annual average values of the concentrations of air pollutants from monitoring sites outside of the biosphere reserve had therefore been subject to geostatistical analysis and estimation. This yields valid information on the spatial patterns and temporal trends of air quality. The approach illustrated is applicable to similar cases, as, for example, the harmonization of international monitoring networks.

Constraining a land-surface model with multiple observations by application of the MPI-Carbon Cycle Data Assimilation System V1.0

NASA Astrophysics Data System (ADS)

Schürmann, Gregor J.; Kaminski, Thomas; Köstler, Christoph; Carvalhais, Nuno; Voßbeck, Michael; Kattge, Jens; Giering, Ralf; Rödenbeck, Christian; Heimann, Martin; Zaehle, Sönke

2016-09-01

We describe the Max Planck Institute Carbon Cycle Data Assimilation System (MPI-CCDAS) built around the tangent-linear version of the JSBACH land-surface scheme, which is part of the MPI-Earth System Model v1. The simulated phenology and net land carbon balance were constrained by globally distributed observations of the fraction of absorbed photosynthetically active radiation (FAPAR, using the TIP-FAPAR product) and atmospheric CO2 at a global set of monitoring stations for the years 2005 to 2009. When constrained by FAPAR observations alone, the system successfully, and computationally efficiently, improved simulated growing-season average FAPAR, as well as its seasonality in the northern extra-tropics. When constrained by atmospheric CO2 observations alone, global net and gross carbon fluxes were improved, despite a tendency of the system to underestimate tropical productivity. Assimilating both data streams jointly allowed the MPI-CCDAS to match both observations (TIP-FAPAR and atmospheric CO2) equally well as the single data stream assimilation cases, thereby increasing the overall appropriateness of the simulated biosphere dynamics and underlying parameter values. Our study thus demonstrates the value of multiple-data-stream assimilation for the simulation of terrestrial biosphere dynamics. It further highlights the potential role of remote sensing data, here the TIP-FAPAR product, in stabilising the strongly underdetermined atmospheric inversion problem posed by atmospheric transport and CO2 observations alone. Notwithstanding these advances, the constraint of the observations on regional gross and net CO2 flux patterns on the MPI-CCDAS is limited through the coarse-scale parametrisation of the biosphere model. We expect improvement through a refined initialisation strategy and inclusion of further biosphere observations as constraints.

Sedimentary evidence for enhanced hydrological cycling in response to rapid carbon release during the early Toarcian oceanic anoxic event

NASA Astrophysics Data System (ADS)

Izumi, Kentaro; Kemp, David B.; Itamiya, Shoma; Inui, Mutsuko

2018-01-01

A pronounced excursion in the carbon-isotope composition of biospheric carbon and coeval seawater warming during the early Toarcian (∼183 Ma) has been linked to the large-scale transfer of 12C-enriched carbon to the oceans and atmosphere. A European bias in the distribution of available data means that the precise pattern, tempo and global expression of this carbon cycle perturbation, and the associated environmental responses, remain uncertain. Here, we present a new cm-scale terrestrial-dominated carbon-isotope record through an expanded lower Toarcian section from Japan that displays a negative excursion pattern similar to marine and terrestrial carbon-isotope records documented from Europe. These new data suggest that 12C-enriched carbon was added to the biosphere in at least one rapid, millennial-scale pulse. Sedimentological analysis indicates a close association between the carbon-isotope excursion and high-energy sediment transport and enhanced fluvial discharge. Together, these data support the hypothesis that a sudden strengthening of the global hydrological cycle occurred in direct and immediate response to rapid carbon release and atmospheric warming.

Effect of Data Assimilation Parameters on The Optimized Surface CO2 Flux in Asia

NASA Astrophysics Data System (ADS)

Kim, Hyunjung; Kim, Hyun Mee; Kim, Jinwoong; Cho, Chun-Ho

2018-02-01

In this study, CarbonTracker, an inverse modeling system based on the ensemble Kalman filter, was used to evaluate the effects of data assimilation parameters (assimilation window length and ensemble size) on the estimation of surface CO2 fluxes in Asia. Several experiments with different parameters were conducted, and the results were verified using CO2 concentration observations. The assimilation window lengths tested were 3, 5, 7, and 10 weeks, and the ensemble sizes were 100, 150, and 300. Therefore, a total of 12 experiments using combinations of these parameters were conducted. The experimental period was from January 2006 to December 2009. Differences between the optimized surface CO2 fluxes of the experiments were largest in the Eurasian Boreal (EB) area, followed by Eurasian Temperate (ET) and Tropical Asia (TA), and were larger in boreal summer than in boreal winter. The effect of ensemble size on the optimized biosphere flux is larger than the effect of the assimilation window length in Asia, but the importance of them varies in specific regions in Asia. The optimized biosphere flux was more sensitive to the assimilation window length in EB, whereas it was sensitive to the ensemble size as well as the assimilation window length in ET. The larger the ensemble size and the shorter the assimilation window length, the larger the uncertainty (i.e., spread of ensemble) of optimized surface CO2 fluxes. The 10-week assimilation window and 300 ensemble size were the optimal configuration for CarbonTracker in the Asian region based on several verifications using CO2 concentration measurements.

The Role of Microbial Electron Transfer in the Coevolution of the Biosphere and Geosphere.

PubMed

Jelen, Benjamin I; Giovannelli, Donato; Falkowski, Paul G

2016-09-08

All life on Earth is dependent on biologically mediated electron transfer (i.e., redox) reactions that are far from thermodynamic equilibrium. Biological redox reactions originally evolved in prokaryotes and ultimately, over the first ∼2.5 billion years of Earth's history, formed a global electronic circuit. To maintain the circuit on a global scale requires that oxidants and reductants be transported; the two major planetary wires that connect global metabolism are geophysical fluids-the atmosphere and the oceans. Because all organisms exchange gases with the environment, the evolution of redox reactions has been a major force in modifying the chemistry at Earth's surface. Here we briefly review the discovery and consequences of redox reactions in microbes with a specific focus on the coevolution of life and geochemical phenomena.

The legacy of biosphere 2 for the study of biospherics and closed ecological systems

NASA Astrophysics Data System (ADS)

Allen, J. P.; Nelson, M.; Alling, A.

The unprecedented challenges of creating Biosphere 2, the world's first laboratory for biospherics, the study of global ecology and long-term closed ecological system dynamics, led to breakthrough developments in many fields, and a deeper understanding of the opportunities and difficulties of material closure. This paper will review accomplishments and challenges, citing some of the key research findings and publications that have resulted from the experiments in Biosphere 2. Engineering accomplishments included development of a technique for variable volume to deal with pressure differences between the facility and outside environment, developing methods of atmospheric leak detection and sealing, while achieving new standards of closure, with an annual atmospheric leakrate of less than 10%, or less than 300 ppm per day. This degree of closure permitted detailed tracking of carbon dioxide, oxygen, and trice gases such as nitrous oxide and ethylene over the seasonal variability of two years. Full closure also necessitated developing new approaches and technologies for complete air, water, and wastewater recycle and reuse within the facility. The development of a soil-based highly productive agricultural system was a first in closed ecological systems, and much was learned about managing a wide variety of crops using non-chemical means of pest and disease control. Closed ecological systems have different temporal biogeochemical cycling and ranges of atmospheric components because of their smaller reservoirs of air, water and soil, and higher concentration of biomass, and Biosphere 2 provided detailed examination and modeling of these accelerated cycles over a period of closure which measured in years. Medical research inside Biosphere 2 included the effects on humans of lowered oxygen: the discovery that human productivity can be maintained with good health with lowered atmospheric oxygen levels could lead to major economies on the design of space stations and planetary/lunar settlements. The improved health resulting from the calorie-restricted but nutrient dense Biosphere 2 diet was the first such scientifically controlled experiment with humans. The success of Biosphere 2 in creating a diversity of terrestrial and marine environments, from rainforest to coral reef, allowed detailed studies with comprehensive measurements such that the dynamics of these complex biomic systems are now better understood. The coral reef ecosystem, the largest artificial reef ever built, catalyzed methods of study now being applied to planetary coral reef systems. Restoration ecology advanced through the creation and study of the dynamics of adaptation and self-organization of the biomes in Biosphere 2. The international interest that Biosphere 2 generated has given new impetus to the public recognition of the sciences of biospheres (biospherics), biomes and closed ecological life systems. The facility, although no longer a materially-closed ecological system, is being used as an educational facility by Columbia University as an introduction to the study of the biosphere and complex system ecology and for carbon dioxide impacts utilizing the complex ecosystems created in Biosphere '.The many lessons learned from Biosphere 2 are being used by its key team of creators in their design and operation of a laboratory-sized closed ecological system, the Laboratory Biosphere, in operation as of March 2002, and for the design of a Mars on Earth ™ prototype life support system for manned missions to Mars and Mars surface habitats. Biosphere 2 is an important foundation for future advances in biospherics and closed ecological system research.

Space nuclear power system and the design of the nuclear electric propulsion OTV

NASA Technical Reports Server (NTRS)

Buden, D.; Garrison, P. W.

1984-01-01

Payload increases of three to five times that of the Shuttle/Centaur can be achieved using nuclear electric propulsion. Various nuclear power plant options being pursued by the SP-100 Program are described. These concepts can grow from 100 kWe to 1 MWe output. Spacecraft design aspects are addressed, including thermal interactions, plume interactions, and radiation fluences. A baseline configuration is described accounting for these issues. Safety aspects of starting the OTV transfer from an altitude of 300 km indicate no significant additional risk to the biosphere.

Phytoforensics, dendrochemistry, and phytoscreening: New green tools for delineating contaminants from past and present

USGS Publications Warehouse

Burken, J.G.; Vroblesky, D.A.; Balouet, J.-C.

2011-01-01

As plants evolved to be extremely proficient in mass transfer with their surroundings and survive as earth's dominant biomass, they also accumulate and store some contaminants from surroundings, acting as passive samplers. Novel applications and analytical methods have been utilized to gain information about a wide range of contaminants in the biosphere soil, water, and air, with information available on both past (dendrochemistry) and present (phytoscreening). Collectively these sampling approaches provide rapid, cheap, ecologically friendly, and overall "green" tools termed "Phytoforensics". ?? 2011 American Chemical Society.

Investigating Atmospheric Mercury with the U.S. Geological Survey Mobile Mercury Laboratory

USGS Publications Warehouse

Kolker, Allan

2007-01-01

Atmospheric mercury is thought to be an important source of mercury present in fish, resulting in numerous local, statewide, tribal, and province-wide fish consumption advisories in the United States and Canada (U.S. Environmental Protection Agency, 2007a). To understand how mercury occurs in the atmosphere and its potential to be transferred from the atmosphere to the biosphere, the U.S. Geological Survey (USGS) has been investigating sources and forms of atmospheric mercury, especially in locations where the amount of mercury deposited from precipitation is above average.

Implementation of the Biosphere Compatibility Principle in Urban Planning: How to Train Next-Generation Specialists

ERIC Educational Resources Information Center

Ivanova, Zinaida Ilyinichna; Yudenkova, Olga Valeryevna; Ishkov, Aleksandr Dmitrievich; Shnyrenkov, Evgeny Anatolyevich

2015-01-01

The co-authors address the relevant issues concerning the need to implement the principle of the biosphere compatibility as the core prerequisite for the symbiotic co-existence of man and nature. Caring treatment of the biosphere, termination of its excessive exploitation, analysis of the ratio between the biospheric potential of specific areas…

The impact of low and intermediate-level radioactive waste on humans and the environment over the next one hundred thousand years.

PubMed

Kautsky, Ulrik; Saetre, Peter; Berglund, Sten; Jaeschke, Ben; Nordén, Sara; Brandefelt, Jenny; Keesmann, Sven; Näslund, Jens-Ove; Andersson, Eva

2016-01-01

In order to assess the potential radiological risk to humans and the environment from a geological repository for radioactive waste, a safety assessment must be performed. This implies that the release and transfer of radionuclides from the repository into the surface environment are calculated and that the effects in the biosphere are evaluated for an assessment period up to one hundred thousand years according to Swedish regulations. This paper discusses the challenges associated with the modelling of surface ecosystems over such long time scales, using the recently completed assessment for the extension of the existing repository for the low- and intermediate-level nuclear waste (called SFR) in Forsmark, Sweden as an applied example. In the assessment, natural variation and uncertainties in climate during the assessment period were captured by using a set of climate cases, primarily reflecting different expectations on the effects of global warming. Development of the landscape at the site, due to post-glacial isostatic rebound, was modelled, and areas where modelling indicated that radionuclides could discharge into the biosphere were identified. Transfers of surface water and groundwater were described with spatially distributed hydrological models. The projected release of radionuclides from the bedrock was then fed into a biosphere radionuclide transport model, simulating the transport and fate of radionuclides within and between ecosystems in the landscape. Annual doses for human inhabitants were calculated by combining activity concentrations in environmental media (soil, water, air and plants) with assumptions on habits and land-use of future human inhabitants. Similarly, dose rates to representative organisms of non-human biota were calculated from activity concentrations in relevant habitats, following the ERICA methodology. In the main scenario, the calculated risk for humans did not exceed the risk criteria or the screening dose rate for non-human biota, indicating that the repository design is sufficient to protect future populations and the environment. Although the combination of radionuclides, land-uses/habitats, type of most exposed population and area of exposure that contribute most to the total dose shifts over time, the total calculated dose shows limited variability. Significant reductions in the dose only occur during submerged periods and under periglacial climate conditions. As several different water and food pathways were equally important for endpoint results, it is concluded that it would be difficult to represent the biosphere with one or a set of simplified models. Instead, we found that it is important to maintain a diversity of food and water pathways, as key pathways for radionuclide accumulation and exposure partly worked in parallel. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Biosphere reserves: Attributes for success.

PubMed

Van Cuong, Chu; Dart, Peter; Hockings, Marc

2017-03-01

Biosphere reserves established under the UNESCO Man and the Biosphere Program aim to harmonise biodiversity conservation and sustainable development. Concerns over the extent to which the reserve network was living up to this ideal led to the development of a new strategy in 1995 (the Seville Strategy) to enhance the operation of the network of reserves. An evaluation of effectiveness of management of the biosphere reserve network was called for as part of this strategy. Expert opinion was assembled through a Delphi Process to identify successful and less successful reserves and investigate common factors influencing success or failure. Ninety biosphere reserves including sixty successful and thirty less successful reserves in 42 countries across all five Man and the Biosphere Program regions were identified. Most successful sites are the post-Seville generation while the majority of unsuccessful sites are pre-Seville that are managed as national parks and have not been amended to conform to the characteristics that are meant to define a biosphere reserve. Stakeholder participation and collaboration, governance, finance and resources, management, and awareness and communication are the most influential factors in the success or failure of the biosphere reserves. For success, the biosphere reserve concept needs to be clearly understood and applied through landscape zoning. Designated reserves then need a management system with inclusive good governance, strong participation and collaboration, adequate finance and human resource allocation and stable and responsible management and implementation. All rather obvious but it is difficult to achieve without commitment to the biosphere reserve concept by the governance authorities. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Impact of Prior Biosphere Models in the Inversion of Global Terrestrial CO2 Fluxes by Assimilating OCO-2 Retrievals

NASA Technical Reports Server (NTRS)

Philip, Sajeev; Johnson, Matthew S.

2018-01-01

Atmospheric mixing ratios of carbon dioxide (CO2) are largely controlled by anthropogenic emissions and biospheric fluxes. The processes controlling terrestrial biosphere-atmosphere carbon exchange are currently not fully understood, resulting in terrestrial biospheric models having significant differences in the quantification of biospheric CO2 fluxes. Atmospheric transport models assimilating measured (in situ or space-borne) CO2 concentrations to estimate "top-down" fluxes, generally use these biospheric CO2 fluxes as a priori information. Most of the flux inversion estimates result in substantially different spatio-temporal posteriori estimates of regional and global biospheric CO2 fluxes. The Orbiting Carbon Observatory 2 (OCO-2) satellite mission dedicated to accurately measure column CO2 (XCO2) allows for an improved understanding of global biospheric CO2 fluxes. OCO-2 provides much-needed CO2 observations in data-limited regions facilitating better global and regional estimates of "top-down" CO2 fluxes through inversion model simulations. The specific objectives of our research are to: 1) conduct GEOS-Chem 4D-Var assimilation of OCO-2 observations, using several state-of-the-science biospheric CO2 flux models as a priori information, to better constrain terrestrial CO2 fluxes, and 2) quantify the impact of different biospheric model prior fluxes on OCO-2-assimilated a posteriori CO2 flux estimates. Here we present our assessment of the importance of these a priori fluxes by conducting Observing System Simulation Experiments (OSSE) using simulated OCO-2 observations with known "true" fluxes.

Reviewing Biosphere Reserves globally: effective conservation action or bureaucratic label?

PubMed

Coetzer, Kaera L; Witkowski, Edward T F; Erasmus, Barend F N

2014-02-01

The Biosphere Reserve (BR) model of UNESCO's Man and the Biosphere Programme reflects a shift towards more accountable conservation. Biosphere Reserves attempt to reconcile environmental protection with sustainable development; they explicitly acknowledge humans, and human interests in the conservation landscape while still maintaining the ecological values of existing protected areas. Conceptually, this model is attractive, with 610 sites currently designated globally. Yet the practical reality of implementing dual 'conservation' and 'development' goals is challenging, with few examples successfully conforming to the model's full criteria. Here, we review the history of Biosphere Reserves from first inception in 1974 to the current status quo, and examine the suitability of the designation as an effective conservation model. We track the spatial expansion of Biosphere Reserves globally, assessing the influence of the Statutory Framework of the World Network of Biosphere Reserves and Seville strategy in 1995, when the BR concept refocused its core objectives on sustainable development. We use a comprehensive range of case studies to discuss conformity to the Programme, the social and ecological consequences associated with implementation of the designation, and challenges in aligning conservation and development. Given that the 'Biosphere Reserve' label is a relatively unknown designation in the public arena, this review also provides details on popularising the Biosphere Reserve brand, as well as prospects for further research, currently unexploited, but implicit in the designation. © 2013 The Authors. Biological Reviews © 2013 Cambridge Philosophical Society.

Anthropogenic transformation of the terrestrial biosphere.

PubMed

Ellis, Erle C

2011-03-13

Human populations and their use of land have transformed most of the terrestrial biosphere into anthropogenic biomes (anthromes), causing a variety of novel ecological patterns and processes to emerge. To assess whether human populations and their use of land have directly altered the terrestrial biosphere sufficiently to indicate that the Earth system has entered a new geological epoch, spatially explicit global estimates of human populations and their use of land were analysed across the Holocene for their potential to induce irreversible novel transformation of the terrestrial biosphere. Human alteration of the terrestrial biosphere has been significant for more than 8000 years. However, only in the past century has the majority of the terrestrial biosphere been transformed into intensively used anthromes with predominantly novel anthropogenic ecological processes. At present, even were human populations to decline substantially or use of land become far more efficient, the current global extent, duration, type and intensity of human transformation of ecosystems have already irreversibly altered the terrestrial biosphere at levels sufficient to leave an unambiguous geological record differing substantially from that of the Holocene or any prior epoch. It remains to be seen whether the anthropogenic biosphere will be sustained and continue to evolve.

[Search for life in deep biospheres].

PubMed

Naganuma, Takeshi

2003-12-01

The life in deep biospheres bridges conventional biology and future exobiology. This review focuses the microbiological studies from the selected deep biospheres, i.e., deep-sea hydrothermal vents, sub-hydrothermal vents, terrestrial subsurface and a sub-glacier lake. The dark biospheres facilitate the emergence of organisms and communities dependent on chemolithoautotrophy, which are overwhelmed by photoautotrophy (photosynthesis) in the surface biospheres. The life at deep-sea hydrothermal vents owes much to chemolithoautotrophy based on the oxidation of sulfide emitted from the vents. It is likely that similarly active bodies such as the Jovian satellite Europa may have hydrothermal vents and associated biological communities. Anoxic or anaerobic condition is characteristic of deep subsurface biospheres. Subsurface microorganisms exploit available oxidants, or terminal electron acceptors (TEA), for anaerobic respiration. Sulfate, nitrate, iron (III) and CO2 are the representative TEAs in the deep subsurface. Below the 3000-4000 m-thick glacier on Antarctica, there have been >70 lakes with liquid water located. One of such sub-glacial lakes, Lake Vostok, is about to be drill-penetrated for microbiological studies. These deep biosphere "platforms" provide new knowledge about the diversity and potential of the Earth's life. The expertise obtained from the deep biosphere expeditions will facilitate the capability of exobiologial exploration.

Resolving the excited state equilibrium of peridinin in solution.

PubMed

Papagiannakis, Emmanouil; Larsen, Delmar S; van Stokkum, Ivo H M; Vengris, Mikas; Hiller, Roger G; van Grondelle, Rienk

2004-12-14

The carotenoid peridinin is abundant in the biosphere, as it is the main pigment bound by the light-harvesting complexes of dinoflagellates, where it collects blue and green sunlight and transfers energy to chlorophyll a with high efficiency. Its molecular structure is particularly complex, giving rise to an intricate excited state manifold, which includes a state with charge-transfer character. To disentangle the excited states of peridinin and understand their function in vivo, we applied dispersed pump-probe and pump-dump-probe spectroscopy. The preferential depletion of population from the intramolecular charge transfer state by the dump pulse demonstrates that the S(1) and this charge transfer state are distinct entities. The ensuing dump-induced dynamics illustrates the equilibration of the two states which occurs on the time scale of a few picoseconds. Additionally, the dump pulse populates a short-lived ground state intermediate, which is suggestive of a complex relaxation pathway, probably including structural reorientation or solvation of the ground state. These findings indicate that the unique intramolecular charge transfer state of peridinin is an efficient energy donor to chlorophyll a in the peridinin-chlorophyll-protein complex and thus plays a significant role in global light harvesting.

Application of Biosphere Compatibility Indicator for Assessment of the Effectiveness of Environmental Protection Methods

NASA Astrophysics Data System (ADS)

Bakaeva, N. V.; Vorobyov, S. A.; Chernyaeva, I. V.

2017-11-01

The article is devoted to the issue of using the biosphere compatibility indicator to assess the effectiveness of environmental protection methods. The indicator biosphere compatibility was proposed by the vice-president of RAASN (Russian Academy of Architecture and Building Sciences), Doctor of Technical Sciences, Professor V.I. Ilyichev. This indicator allows one to assess not only qualitatively but also quantitatively the degree of urban areas development from the standpoint of preserving the biosphere in urban ecosystems while performing the city’s main functions. The integral biosphere compatibility indicator allows us to assess not only the current ecological situation in the territory under consideration but also to plan the forecast of its changes for the new construction projects implementation or for the reconstruction of the existing ones. The biosphere compatibility indicator, which is a mathematical expression of the tripartite balance (technosphere, biosphere and population of this area), allows us to quantify the effectiveness degree of different methods for environment protection to choose the most effective one under these conditions.

Feedbacks between climate change and biosphere integrity

NASA Astrophysics Data System (ADS)

Lade, Steven; Anderies, J. Marty; Donges, Jonathan; Steffen, Will; Rockström, Johan; Richardson, Katherine; Cornell, Sarah; Norberg, Jon; Fetzer, Ingo

2017-04-01

The terrestrial and marine biospheres sink substantial fractions of human fossil fuel emissions. How the biosphere's capacity to sink carbon depends on biodiversity and other measures of biosphere integrity is however poorly understood. Here, we (1): review assumptions from literature regarding the relationships between the carbon cycle and the terrestrial and marine biospheres; and (2) explore the consequences of these different assumptions for climate feedbacks using the stylised carbon cycle model PB-INT. We find that: terrestrial biodiversity loss could significantly dampen climate-carbon cycle feedbacks; direct biodiversity effects, if they exist, could rival temperature increases from low-emission trajectories; and the response of the marine biosphere is critical for longer term climate change. Simple, low-dimensional climate models such as PB-INT can help assess the importance of still unknown or controversial earth system processes such as biodiversity loss for climate feedbacks. This study constitutes the first detailed study of the interactions between climate change and biosphere integrity, two of the 'planetary boundaries'.

Biosphere Reserve for All: Potentials for Involving Underrepresented Age Groups in the Development of a Biosphere Reserve through Intergenerational Practice.

PubMed

Mitrofanenko, Tamara; Snajdr, Julia; Muhar, Andreas; Penker, Marianne; Schauppenlehner-Kloyber, Elisabeth

2018-05-22

Stakeholder participation is of high importance in UNESCO biosphere reserves as model regions for sustainable development; however, certain groups remain underrepresented. The paper proposes Intergenerational Practice (IP) as a means of involving youth and elderly women and explores its options and barriers, using the example of the Salzburger Lungau and Kärntner Nockberge Biosphere Reserve in Austria. Case study analysis is used involving mixed methods. The results reveal obstacles and motivations to participating in biosphere reserve implementation and intergenerational activities for the youth and the elderly women and imply that much potential for IP exists in the biosphere reserve region. The authors propose suitable solutions from the intergenerational field to overcome identified participation obstacles and suggest benefits of incorporating IP as a management tool into biosphere reserve activities. Suggestions for future research include evaluating applications of IP in the context of protected areas, testing of methods used in other contexts, and contribution to theory development.

Southern Appalachian Man and the Biosphere - SAMAB.ORG

Science.gov Websites

Southern Appalachian Man and the Biosphere Home Who We Are SAMAB Initiatives Archives Welcome to SAMAB This slideshow requires JavaScript. The Southern Appalachian Man and the Biosphere (SAMAB

The typological approach to submarine groundwater discharge (SGD)

USGS Publications Warehouse

Bokuniewicz, H.; Buddemeier, R.; Maxwell, B.; Smith, C.

2003-01-01

Coastal zone managers need to factor submarine groundwater discharge (SGD) in their integration. SGD provides a pathway for the transfer of freshwater, and its dissolved chemical burden, from the land to the coastal ocean. SGD reduces salinities and provides nutrients to specialized coastal habitats. It also can be a pollutant source, often undetected, causing eutrophication and triggering nuisance algal blooms. Despite its importance, SGD remains somewhat of a mystery in most places because it is usually unseen and difficult to measure. SGD has been directly measured at only about a hundred sites worldwide. A typology generated by the Land-Ocean Interaction in the Coastal Zone (LOICZ) Project is one of the few tools globally available to coastal resource managers for identifying areas in their jurisdiction where SGD may be a confounding process. (LOICZ is a core project of the International Geosphere/Biosphere Programme.) Of the hundreds of globally distributed parameters in the LOICZ typology, a SGD subset of potentially relevant parameters may be culled. A quantitative combination of the relevant hydrological parameters can serve as a proxy for the SGD conditions not directly measured. Web-LOICZ View, geospatial software then provides an automated approach to clustering these data into groups of locations that have similar characteristics. It permits selection of variables, of the number of clusters desired, and of the clustering criteria, and provides means of testing predictive results against independent variables. Information on the occurrence of a variety of SGD indicators can then be incorporated into regional clustering analysis. With such tools, coastal managers can focus attention on the most likely sites of SGD in their jurisdiction and design the necessary measurement and modeling programs needed for integrated management.

Ciliates and the rare biosphere-community ecology and population dynamics.

PubMed

Weisse, Thomas

2014-01-01

Application of deep sequencing technologies to environmental samples and some detailed morphological studies suggest that there is a vast, yet unexplored rare ciliate biosphere, tentatively defined in terms of operational taxonomic units. However, very few studies complemented molecular and phylogenetic data with morphological and ecological descriptions of the species inventory. This is mainly because the sampling effort increases strongly with decreasing species abundance. In spite of this limited knowledge, it is clear that species that are rare under certain environmental conditions (temporal rare biosphere) may become abundant when the physical, chemical, and biological variables of their habitat change. Furthermore, some species may always be present in low numbers if their dispersal rates are exceedingly high (accidental rare biosphere). An intriguing question is whether there are some species that are always rare, i.e., in every suitable environment. This permanent rare biosphere is conceptually different from the temporal rare biosphere. This review characterizes typical aquatic habitats of the rare ciliate biosphere, portrays different scenarios under which some or even many species may be permanently rare (background fauna), and identifies some fundamental questions that need to be addressed to achieve a better understanding of the population dynamics of the rare ciliate biosphere. © 2014 The Authors The Journal of Eukaryotic Microbiology published by Wiley Periodicals, Inc. on behalf of International Society of Protistologists.

Historical overview of the Biosphere 2 project

NASA Technical Reports Server (NTRS)

Allen, John P.

1990-01-01

An extensive historical overview is given of the Biosphere 2 project. The overview begins in late 1969, as the moon landings commenced, when work began on ecological projects which laid the conceptual foundation for the current Biosphere 2 project. Continuing through to taking a complete functional suite of microbes together with their associated aquatic elements and an air volume and putting them inside a closed lab flask in which to measure the oxygen and CO2 levels, study energy flows and visually observe the changes therein. The laws of biospherics formulated by the author which can be tested in the Biosphere 2 project are listed.

Interpretation of Biosphere Reserves.

ERIC Educational Resources Information Center

Merriman, Tim

1994-01-01

Introduces the Man and the Biosphere Programme (MAB) to monitor the 193 biogeographical provinces of the Earth and the creation of biosphere reserves. Highlights the need for interpreters to become familiar or involved with MAB program activities. (LZ)

Biomedical program at Space Biospheres Ventures

NASA Technical Reports Server (NTRS)

Walford, Roy

1990-01-01

There are many similarities and some important differences between potential health problems of Biosphere 2 and those of which might be anticipated for a space station or a major outpost on Mars. The demands of time, expense, and equipment would not readily allow medical evacuation from deep space for a serious illness or major trauma, whereas personnel can easily be evacuated from Biosphere 2 if necessary. Treatment facilities can be somewhat less inclusive, since distance would not compel the undertaking of heroic measures or highly complicated surgical procedures on site, and with personnel not fully trained for these procedures. The similarities are given between medical requirements of Biosphere 2 and the complex closed ecological systems of biospheres in space or on Mars. The major problems common to all these would seem to be trauma, infection, and toxicity. It is planned that minor and moderate degrees of trauma, including debridement and suturing of wounds, x ray study of fractures, will be done within Biosphere 2. Bacteriologic and fungal infections, and possibly allergies to pollen or spores are expected to be the commonest medical problem within Biosphere 2.

Use of the method of biosphere compatibility for the assessment of environmental protection methods

NASA Astrophysics Data System (ADS)

Vorobyov, Sergey

2018-01-01

The article is devoted to the question of using the indicator of biosphere compatibility for assessing the effectiveness of environmental protection methods. The indicator of biosphere compatibility was proposed by the vice-president of RAASN (Russian Academy of Architecture and Building Sciences), Doctor of Technical Sciences, Professor V.I. Ilyichev. This indicator is allows not only qualitatively but also quantitatively to assess the degree of development of urban urban areas, from the standpoint of preserving the biosphere in urban ecosystems while realizing the city’s main functions. The integral indicator of biosphere compatibility is allows us to assess not only the current ecological situation in the territory under consideration, but also to plan the forecast of its changes for building the new construction projects, or for reconstructing existing ones. The indicator of biosphere compatibility, which is a mathematical expression of the tripartite balance (technosphere, biosphere and population of this area), is allows us to quantify the degree of effectiveness of different method of protecting the environment for choose the most effective for these conditions.

The Legacy of Biosphere 2 for Biospherics and Closed Ecological System Research

NASA Astrophysics Data System (ADS)

Allen, J.; Alling, A.; Nelson, M.

The unprecedented challenges of creating Biosphere 2, the world's first laboratory for biospherics, the study of global ecology and long-term closed ecological system dynamics led to breakthrough developments in many fields, and a deeper understanding of the opportunities and difficulties of material closure. This paper will review these accomplishments and challenges, citing some of the key research accomplishments and publications which have resulted from the experiments in Biosphere 2. Engineering accomplishments included development of a technique for variable volume to deal with pressure differences between the facility and outside environment, developing methods of leak detection and sealing, and achieving new standards of closure, with an annual atmospheric leakrate of less than 10%, or less than 300 ppm per day. This degree of closure permitted detailed tracking of carbon dioxide, oxygen, and trace gases such as nitrous oxide and ethylene over the seasonal variability of two years. Full closure also necessitated developing new approaches and technologies for complete air, water, and wastewater recycle and reuse within the facility. The development of a soil-based highly productive agricultural system was a first in closed ecological systems, and much was learned about managing a wide variety of crops using non-chemical means of pest and disease control. Closed ecological systems have different temporal b ogeochemical cycling and ranges ofi atmospheric components because of their smaller reservoirs of air, water and soil, and higher concentration of biomass, and Biosphere 2 provided detailed examination and modeling of these accelerated cycles over a period of closure which measured in years. Medical research inside Biosphere 2 included the effects on humans of lowered oxygen: the discovery that human productivity can be maintained down to 15% oxygen could lead to major economies on the design of space stations and planetary/lunar settlements. The improved health resulting from the calorie-restricted but nutrient dense Biosphere 2 diet was the first such scientifically-controlled experiment with humans. The success of Biosphere in creating a diversity of terrestrial and marine environments, from rainforest to coral reef, allowed detailed studies with comprehensive measurements such that the dynamics of these complex biomic systems can be better understood. The coral reef ecosystem, the largest artificial reef ever built, catalyzed methods of study now being applied to planetary coral reef systems. Restoration ecology can learn much from the creation and dynamics of adaptation of the biomes in Biosphere 2. The international interest that Biosphere 2 generated has given new impetus to the public recognition of the sciences of biospheres, biospherics, biomes and closed ecological life systems. The facility is still being used as an educational facility by Columbia University as an introduction to the study of the biosphere and complex system ecology. The many lessons learned from Biosphere 2, from its successes, surprises and challenges, is being used by its key team of creators as the foundations for their design of a laboratory-sized closed ecological system and Mars on Earth prototype life support system for Mars exploration and can be an important foundation for future advances in biospherics and closed ecological system research.

Calibration of the ``Simplified Simple Biosphere Model—SSiB'' for the Brazilian Northeast Caatinga

NASA Astrophysics Data System (ADS)

do Amaral Cunha, Ana Paula Martins; dos Santos Alvalá, Regina Célia; Correia, Francis Wagner Silva; Kubota, Paulo Yoshio

2009-03-01

The Brazilian Northeast region is covered largely by vegetation adapted to the arid conditions and with varied physiognomy, called caatinga. It occupies an extension of about 800.000 km2 that corresponds to 70% of the region. In recent decades, considerable progress in understanding the micrometeorological processes has been reached, with results that were incorporated into soil-vegetation-atmosphere transfer schemes (SVATS) to study the momentum, energy, water vapor, carbon cycle and vegetation dynamics changes of different ecosystems. Notwithstanding, the knowledge of the parameters and physical or physiological characteristics of the vegetation and soil of the caatinga region is very scarce. So, the objective of this work was performing a calibration of the parameters of the SSiB model for the Brazilian Northeast Caatinga. Micrometeorological and hydrological data collected from July 2004 to June 2005, obtained in the Agricultural Research Center of the Semi-Arid Tropic (CPATSA), were used. Preceding the calibration process, a sensibility study of the SSiB model was performed in order to find the parameters that are sensible to the exchange processes between the surface and atmosphere. The results showed that the B parameter, soil moisture potential at saturation (ψs), hydraulic conductivity of saturated soil (ks) and the volumetric moisture at saturation (θs) present high variations on turbulent fluxes. With the initial parameters, the SSiB model showed best results for net radiation, and the latent heat (sensible heat) flux was over-estimated (under-estimated) for all simulation periods. Considering the calibrated parameters, better values of latent flux and sensible flux were obtained. The calibrated parameters were also used for a validation of the surface fluxes considering data from July 2005 to September 2005. The results showed that the model generated better estimations of latent heat and sensible heat fluxes, with low root mean square error. With better estimations of the turbulent fluxes, it was possible to obtain a more representative energy partitioning for the caatinga. Therefore, it is expected that from this calibrated SSiB model, coupled to the meteorological models, it will be possible to obtain more realistic climate and weather forecasts for the Brazilian Northeast region.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Napier, Bruce A.; Fellows, Robert J.; Krupka, Kenneth M.

This report describes work performed for the U.S. Nuclear Regulatory Commission’s project Assessment of Food Chain Pathway Parameters in Biosphere Models, which was established to assess and evaluate a number of key parameters used in the food-chain models used in performance assessments of radioactive waste disposal facilities. Section 2 of this report summarizes characteristics of samples of soils and groundwater from three geographical regions of the United States, the Southeast, Northwest, and Southwest, and analyses performed to characterize their physical and chemical properties. Because the uptake and behavior of radionuclides in plant roots, plant leaves, and animal products depends onmore » the chemistry of the water and soil coming in contact with plants and animals, water and soil samples collected from these regions of the United States were used in experiments at Pacific Northwest National Laboratory to determine radionuclide soil-to-plant concentration ratios. Crops and forage used in the experiments were grown in the soils, and long-lived radionuclides introduced into the groundwater provide the contaminated water used to water the grown plants. The radionuclides evaluated include 99Tc, 238Pu, and 241Am. Plant varieties include alfalfa, corn, onion, and potato. The radionuclide uptake results from this research study show how regional variations in water quality and soil chemistry affect radionuclide uptake. Section 3 summarizes the procedures and results of the uptake experiments, and relates the soil-to-plant uptake factors derived. In Section 4, the results found in this study are compared with similar values found in the biosphere modeling literature; the study’s results are generally in line with current literature, but soil- and plant-specific differences are noticeable. This food-chain pathway data may be used by the NRC staff to assess dose to persons in the reference biosphere (e.g., persons who live and work in an area potentially affected by radionuclide releases) of waste disposal facilities and decommissioning sites.« less

The Biosphere.

ERIC Educational Resources Information Center

Cloud, Preston

1983-01-01

Discusses the earth's biosphere, considering how the microbial, animal and plant life (which make up the biosphere) are sustained by the earth's lithosphere, hydrosphere, and atmosphere. Also considers how these three earth features have powerfully shaped the evolution of these organisms. (JN)

Swansong biospheres II: the final signs of life on terrestrial planets near the end of their habitable lifetimes

NASA Astrophysics Data System (ADS)

O'Malley-James, Jack T.; Cockell, Charles S.; Greaves, Jane S.; Raven, John A.

2014-07-01

The biosignatures of life on Earth do not remain static, but change considerably over the planet's habitable lifetime. Earth's future biosphere, much like that of the early Earth, will consist of predominantly unicellular microorganisms due to the increased hostility of environmental conditions caused by the Sun as it enters the late stage of its main sequence evolution. Building on previous work, the productivity of the biosphere is evaluated during different stages of biosphere decline between 1 and 2.8 Gyr from present. A simple atmosphere-biosphere interaction model is used to estimate the atmospheric biomarker gas abundances at each stage and to assess the likelihood of remotely detecting the presence of life in low-productivity, microbial biospheres, putting an upper limit on the lifetime of Earth's remotely detectable biosignatures. Other potential biosignatures such as leaf reflectance and cloud cover are discussed.

NEW DIRECTIONS: VOCS AND BIOSPHERE-ATMOSPHERE FEEDBACKS

EPA Science Inventory

Shallcross and Monks [New Directions: a Role For Isoprene in Biosphere-Climate-Chemistry Feedbacks, Atmospheric Environment, Vol. 34 (2000) pp. 1659-1660] recently summarized the importance of biogenic isoprene in a biosphere-atmosphere system under constant change. In this art...

Estimating the seasonal carbon source-sink geography of a natural, steady-state terrestrial biosphere

NASA Technical Reports Server (NTRS)

Box, Elgene O.

1988-01-01

The estimation of the seasonal dynamics of biospheric-carbon sources and sinks to be used as an input to global atmospheric CO2 studies and models is discussed. An ecological biosphere model is given and the advantages of the model are examined. Monthly maps of estimated biospheric carbon source and sink regions and estimates of total carbon fluxes are presented for an equilibrium terrestrial biosphere. The results are compared with those from other models. It is suggested that, despite maximum variations of atmospheric CO2 in boreal latitudes, the enormous contributions of tropical wet-dry regions to global atmospheric CO2 seasonality can not be ignored.

The Cretaceous-Tertiary boundary marine extinction and global primary productivity collapse

NASA Technical Reports Server (NTRS)

Zachos, J. C.; Arthus, M. A.; Dean, W. E.

1988-01-01

The extinction of marine phyto-and zoo-plankton across the K-T boundary has been well documented. Such an event may have resulted in decreased photosynthetic fixation of carbon in surface waters and a collapse of the food chain in the marine biosphere. Because the vertical and horizontal distribution of the carbon isotopic composition of total dissolved carton (TDC) in the modern ocean is controlled by the transfer of organic carbon from the surface to deep reservoirs, it follows that a major disruption of the marine biosphere would have had a major effect on the distribution of carbon isotopes in the ocean. Negative carbon isotope excursions have been identified at many marine K-T boundary sequences worldwide and are interpreted as a signal of decreased oceanic primary productivity. However, the magnitude, duration and consequences of this productivity crisis have been poorly constrained. On the basis of planktonic and benthic calcareous microfossil carbon isotope and other geochemical data from DSDP Site 577 located on the Shatsky Rise in the north-central Pacific, as well as other sites, researchers have been able to provide a reasonable estimate of the duration and magnitude of this event.

Biosphere 2: The True Story.

ERIC Educational Resources Information Center

O'Keeffe, Michael

1992-01-01

Discusses the history and current developments of the Biosphere 2 Project, a prototype for enclosed self-sustaining structures for space colonization built in the Arizona Desert. Biosphere 2 was created to educate and provide solutions to environmental problems and revenue from research. (MCO)

Evaluation of severe accident risks: Quantification of major input parameters: MAACS (MELCOR Accident Consequence Code System) input

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sprung, J.L.; Jow, H-N; Rollstin, J.A.

1990-12-01

Estimation of offsite accident consequences is the customary final step in a probabilistic assessment of the risks of severe nuclear reactor accidents. Recently, the Nuclear Regulatory Commission reassessed the risks of severe accidents at five US power reactors (NUREG-1150). Offsite accident consequences for NUREG-1150 source terms were estimated using the MELCOR Accident Consequence Code System (MACCS). Before these calculations were performed, most MACCS input parameters were reviewed, and for each parameter reviewed, a best-estimate value was recommended. This report presents the results of these reviews. Specifically, recommended values and the basis for their selection are presented for MACCS atmospheric andmore » biospheric transport, emergency response, food pathway, and economic input parameters. Dose conversion factors and health effect parameters are not reviewed in this report. 134 refs., 15 figs., 110 tabs.« less

Erosion of organic carbon in the Arctic as a geological carbon dioxide sink.

PubMed

Hilton, Robert G; Galy, Valier; Gaillardet, Jérôme; Dellinger, Mathieu; Bryant, Charlotte; O'Regan, Matt; Gröcke, Darren R; Coxall, Helen; Bouchez, Julien; Calmels, Damien

2015-08-06

Soils of the northern high latitudes store carbon over millennial timescales (thousands of years) and contain approximately double the carbon stock of the atmosphere. Warming and associated permafrost thaw can expose soil organic carbon and result in mineralization and carbon dioxide (CO2) release. However, some of this soil organic carbon may be eroded and transferred to rivers. If it escapes degradation during river transport and is buried in marine sediments, then it can contribute to a longer-term (more than ten thousand years), geological CO2 sink. Despite this recognition, the erosional flux and fate of particulate organic carbon (POC) in large rivers at high latitudes remains poorly constrained. Here, we quantify the source of POC in the Mackenzie River, the main sediment supplier to the Arctic Ocean, and assess its flux and fate. We combine measurements of radiocarbon, stable carbon isotopes and element ratios to correct for rock-derived POC. Our samples reveal that the eroded biospheric POC has resided in the basin for millennia, with a mean radiocarbon age of 5,800 ± 800 years, much older than the POC in large tropical rivers. From the measured biospheric POC content and variability in annual sediment yield, we calculate a biospheric POC flux of 2.2(+1.3)(-0.9) teragrams of carbon per year from the Mackenzie River, which is three times the CO2 drawdown by silicate weathering in this basin. Offshore, we find evidence for efficient terrestrial organic carbon burial over the Holocene period, suggesting that erosion of organic carbon-rich, high-latitude soils may result in an important geological CO2 sink.

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

For nearly 20 years, biosphere reserves have offered a unique framework for building the knowledge, skills, and attitudes required for conservation and sustainable use of ecosystems. The 12 case studies in this volume chronicle many of the cooperative efforts to implement the biosphere reserve concept in the United States. Considered together, these efforts involve more than 20 types of protected areas, and the participation of all levels of government, and many private organizations, academic institutions, citizens groups, and individuals. Biosphere reserves are multi-purpose areas that are nominated by the national committee of the Man and the Biosphere Program (MAB) andmore » designated by the United Nations Educational, Scientific and Cultural Organization (UNESCO) to serve as demonstration areas for cooperation in building harmonious relationships between human activities and the conservation of ecosystems and biological diversity. Each biosphere reserve exemplifies the characteristic ecosystems of one of the worlds biogeographical regions. It is a land or coas%arine area involving human communities as integral components and including resources managed for objectives ranging from complete protection to intensive, yet sustainable development. A biosphere reserve is envisioned as a regional ''landscape for learning'' in which monitoring, research, education, and training are encouraged to support sustainable conservation of natural and managed ecosystems. It is a framework for regional cooperation involving government decisionmakers, scientists, resource managers, private organizations and local people (i.e., the biosphere reserve ''stakeholders''). Finally, each biosphere reserve is part of a global network for sharing information and experience to help address complex problems of conservation and development. The 12 case studies presented in this report represent only a few of the possible evolutions of a biosphere reserve in its efforts to reach out to the local and regional community. As you have read, some have had great success, while others consider their successes almost negligible. All document tremendous effort from many people to improve the communication among landowners, land managers, scientists, and any others interested in the health and well-being of the natural and human environment of the biosphere reserve.« less

Biosphere 2: a prototype project for a permanent and evolving life system for Mars base.

PubMed

Nelson, M; Allen, J P; Dempster, W F

1992-01-01

As part of the ground-based preparation for creating long-term life systems needed for space habitation and settlement, Space Biospheres Ventures (SBV) is undertaking the Biosphere 2 project near Oracle, Arizona. Biosphere 2, currently under construction, is scheduled to commence its operations in 1991 with a two-year closure period with a crew of eight people. Biosphere 2 is a facility which will be essentialy materially-closed to exchange with the outside environment. It is open to information and energy flow. Biosphere 2 is designed to achieve a complex life-support system by the integration of seven areas or "biomes"--rainforest, savannah, desert, marsh, ocean, intensive agriculture and human habitat. Unique bioregenerative technologies, such as soil bed reactors for air purification, aquatic waste processing systems, real-time analytic systems and complex computer monitoring and control systems are being developed for the Biosphere 2 project. Its operation should afford valuable insight into the functioning of complex life systems necessary for long-term habitation in space. It will serve as an experimental ground-based prototype and testbed for the stable, permanent life systems needed for human exploration of Mars.

Genomic Evidence of Chemotrophic Metabolisms in Deep-Dwelling Chloroflexi Conferred by Ancient Horizontal Gene Transfer Events

NASA Astrophysics Data System (ADS)

Momper, L. M.; Magnabosco, C.; Amend, J.; Osburn, M. R.; Fournier, G. P.

2017-12-01

The marine and terrestrial subsurface biospheres represent quite likely the largest reservoirs for life on Earth, directly impacting surface processes and global cycles throughout Earth's history. In the deep subsurface biosphere (DSB) organic carbon and energy are often extremely scarce. However, archaea and bacteria are able to persist in the DSB to at least 3.5 km below surface [1]. Understanding how they persist, and by what metabolisms they subsist, are key questions in this biosphere. To address these questions we investigated 5 global DSB environments: one legacy mine in South Dakota, USA, 3 mines in South Africa and marine fluids circulating beneath the Juan de Fuca Ridge. Boreholes within these mines provided access to fluids buried beneath the earth's surface and sampled depths down to 3.1 km. Geochemical data were collected concomitantly with DNA for metagenomic sequencing. We examined genomes of the ancient and deeply branching Chloroflexi for metabolic capabilities and interrogated the geochemical drivers behind those metabolisms with in situ thermodynamic modeling of reaction energetics. In total, 23 Chloroflexi genomes were identified and analyzed from the 5 subsurface sites. Genes for nitrate reduction (nar) and sulfite reduction (dsr) were found in many of the South Africa Chloroflexi but were absent from genomes collected in South Dakota. Indeed, nitrate reduction was among the most energetically favorable reactions in South African fluids (10-14 kJ cell-1 sec -1 per mol of reactant) and sulfur reduction with Fe2+ or H2 was also exergonic [2]. Conversely, genes for nitrite and nitrous oxide reduction (nrf, nir and nos) were found in genomes collected in South Dakota and Juan de Fuca, but not South Africa. We examined the origin of genes conferring these metabolisms in the Chloroflexi genomes. We discovered evidence for horizontal gene transfer (HGT) for all of these putative metabolisms. Retention of these genes in Chloroflexi lineages indicates HGT may have conferred an advantageous metabolism in DSB environments. We are using molecular dating techniques to constrain the timing of these HGT events on geologic timescales. [1] Baker J. B. et al. (2003) Environ Microbiol., 5, 267-277. [2] Magnabosco C. et al. (2016) ISME J, 10(3), 730-741.

The First International Biosphere Reserve Congress.

ERIC Educational Resources Information Center

Laird, John

1984-01-01

Presents objectives (and related activities) of a plan designed for international collaboration in conserving key natural areas (biosphere reserves) of the globe. The plan (focusing on such areas as management, conservation, research, monitoring, and environmental education/training) was formulated during the First International Biosphere Reserve…

Global carbon export from the terrestrial biosphere controlled by erosion.

PubMed

Galy, Valier; Peucker-Ehrenbrink, Bernhard; Eglinton, Timothy

2015-05-14

Riverine export of particulate organic carbon (POC) to the ocean affects the atmospheric carbon inventory over a broad range of timescales. On geological timescales, the balance between sequestration of POC from the terrestrial biosphere and oxidation of rock-derived (petrogenic) organic carbon sets the magnitude of the atmospheric carbon and oxygen reservoirs. Over shorter timescales, variations in the rate of exchange between carbon reservoirs, such as soils and marine sediments, also modulate atmospheric carbon dioxide levels. The respective fluxes of biospheric and petrogenic organic carbon are poorly constrained, however, and mechanisms controlling POC export have remained elusive, limiting our ability to predict POC fluxes quantitatively as a result of climatic or tectonic changes. Here we estimate biospheric and petrogenic POC fluxes for a suite of river systems representative of the natural variability in catchment properties. We show that export yields of both biospheric and petrogenic POC are positively related to the yield of suspended sediment, revealing that POC export is mostly controlled by physical erosion. Using a global compilation of gauged suspended sediment flux, we derive separate estimates of global biospheric and petrogenic POC fluxes of 157(+74)(-50) and 43(+61)(-25) megatonnes of carbon per year, respectively. We find that biospheric POC export is primarily controlled by the capacity of rivers to mobilize and transport POC, and is largely insensitive to the magnitude of terrestrial primary production. Globally, physical erosion rates affect the rate of biospheric POC burial in marine sediments more strongly than carbon sequestration through silicate weathering. We conclude that burial of biospheric POC in marine sediments becomes the dominant long-term atmospheric carbon dioxide sink under enhanced physical erosion.

The General Laws of Chemical Elements Composition Dynamics in the Biosphere

NASA Astrophysics Data System (ADS)

Korzh, Vyacheslav D.

2013-04-01

The key point of investigation of the specificity of the biosphere elemental composition formation is determination of patterns of redistribution of elemental average concentrations among various phases, like solid - liquid ( the lithosphere - the hydrosphere), which occurs as a result of a global continuous processing of inert matter by living substances. Our task here is to investigate this process in the system "lithosphere - hydrosphere" in view of the integrated involvement of living material in it. This process is most active in biogeochemical barriers, i.e. in places of "the life condensation" and runs under a nonlinear regularity that has been unknown before. It is established that this process results in a general relative increase in concentrations of chemical elements in the solid phase in proportion as their prevalence in the environment is reduced. This process running in various natural systems has practically the same parameter of nonlinearity (v) approximately equal to 0.7. For proto-lithosphere -"living material" - soil v = 0.75. For river - "living material" - ocean v = 0.67. For the contemporary factual awareness level these estimations of nonlinearity indices are practically negligible. Hence, it is for the first time that the existence of a universal constant of nonlinearity of elemental composition evolution in the biosphere has been proved and its quantitative evaluation has been made. REFERENCES 1. Korzh V.D. 1974. Some general laws governing the turnover of substance within the ocean-atmosphere-continent-ocean cycle. // Journal de Recherches Atmospheriques. Vol. 8. P. 653-660. 2. Korzh V.D. 2008. The general laws in the formation of the elemental composition of the Hydrosphere and Biosphere.// J. Ecologica, Vol. XV, P. 13-21. 3. Korzh V.D. 2012. Determination of general laws of elemental composition in Hydrosphere // Water: chemistry & ecology, Journal of water science and its practical application. # 1, P.56-62.

Appraising the capability of a land biosphere model as a tool in modelling land surface interactions: results from its validation at selected European ecosystems

NASA Astrophysics Data System (ADS)

North, M. R.; Petropoulos, G. P.; Ireland, G.; McCalmont, J. P.

2015-02-01

In this present study the ability of the SimSphere Soil Vegetation Atmosphere Transfer (SVAT) model in estimating key parameters characterising land surface interactions was evaluated. Specifically, SimSphere's performance in predicting Net Radiation (Rnet), Latent Heat (LE), Sensible Heat (H) and Air Temperature (Tair) at 1.3 and 50 m was examined. Model simulations were validated by ground-based measurements of the corresponding parameters for a total of 70 days of the year 2011 from 7 CarboEurope network sites. These included a variety of biomes, environmental and climatic conditions in the models evaluation. Overall, model performance can largely be described as satisfactory for most of the experimental sites and evaluated parameters. For all model parameters compared, predicted H fluxes consistently obtained the highest agreement to the in-situ data in all ecosystems, with an average RMSD of 55.36 W m-2. LE fluxes and Rnet also agreed well with the in-situ data with RSMDs of 62.75 and 64.65 W m-2 respectively. A good agreement between modelled and measured LE and H fluxes was found, especially for smoothed daily flux trends. For both Tair 1.3 m and Tair 50 m a mean RMSD of 4.14 and 3.54 °C was reported respectively. This work presents the first all-inclusive evaluation of SimSphere, particularly so in a European setting. Results of this study contribute decisively towards obtaining a better understanding of the model's structure and its correspondence to the real world system. Findings also further establish the model's capability as a useful teaching and research tool in modelling Earth's land surface interactions. This is of considerable importance in the light of the rapidly expanding use of the model worldwide, including ongoing research by various Space Agencies examining its synergistic use with Earth Observation data towards the development of operational products at a global scale.

A multi-model assessment of terrestrial biosphere model data needs

NASA Astrophysics Data System (ADS)

Gardella, A.; Cowdery, E.; De Kauwe, M. G.; Desai, A. R.; Duveneck, M.; Fer, I.; Fisher, R.; Knox, R. G.; Kooper, R.; LeBauer, D.; McCabe, T.; Minunno, F.; Raiho, A.; Serbin, S.; Shiklomanov, A. N.; Thomas, A.; Walker, A.; Dietze, M.

2017-12-01

Terrestrial biosphere models provide us with the means to simulate the impacts of climate change and their uncertainties. Going beyond direct observation and experimentation, models synthesize our current understanding of ecosystem processes and can give us insight on data needed to constrain model parameters. In previous work, we leveraged the Predictive Ecosystem Analyzer (PEcAn) to assess the contribution of different parameters to the uncertainty of the Ecosystem Demography model v2 (ED) model outputs across various North American biomes (Dietze et al., JGR-G, 2014). While this analysis identified key research priorities, the extent to which these priorities were model- and/or biome-specific was unclear. Furthermore, because the analysis only studied one model, we were unable to comment on the effect of variability in model structure to overall predictive uncertainty. Here, we expand this analysis to all biomes globally and a wide sample of models that vary in complexity: BioCro, CABLE, CLM, DALEC, ED2, FATES, G'DAY, JULES, LANDIS, LINKAGES, LPJ-GUESS, MAESPA, PRELES, SDGVM, SIPNET, and TEM. Prior to performing uncertainty analyses, model parameter uncertainties were assessed by assimilating all available trait data from the combination of the BETYdb and TRY trait databases, using an updated multivariate version of PEcAn's Hierarchical Bayesian meta-analysis. Next, sensitivity analyses were performed for all models across a range of sites globally to assess sensitivities for a range of different outputs (GPP, ET, SH, Ra, NPP, Rh, NEE, LAI) at multiple time scales from the sub-annual to the decadal. Finally, parameter uncertainties and model sensitivities were combined to evaluate the fractional contribution of each parameter to the predictive uncertainty for a specific variable at a specific site and timescale. Facilitated by PEcAn's automated workflows, this analysis represents the broadest assessment of the sensitivities and uncertainties in terrestrial models to date, and provides a comprehensive roadmap for constraining model uncertainties through model development and data collection.

Living microbial ecosystems within the active zone of catagenesis: Implications for feeding the deep biosphere

NASA Astrophysics Data System (ADS)

Horsfield, B.; Schenk, H. J.; Zink, K.; Ondrak, R.; Dieckmann, V.; Kallmeyer, J.; Mangelsdorf, K.; di Primio, R.; Wilkes, H.; Parkes, R. J.; Fry, J.; Cragg, B.

2006-06-01

Earth's largest reactive carbon pool, marine sedimentary organic matter, becomes increasingly recalcitrant during burial, making it almost inaccessible as a substrate for microorganisms, and thereby limiting metabolic activity in the deep biosphere. Because elevated temperature acting over geological time leads to the massive thermal breakdown of the organic matter into volatiles, including petroleum, the question arises whether microorganisms can directly utilize these maturation products as a substrate. While migrated thermogenic fluids are known to sustain microbial consortia in shallow sediments, an in situ coupling of abiotic generation and microbial utilization has not been demonstrated. Here we show, using a combination of basin modelling, kinetic modelling, geomicrobiology and biogeochemistry, that microorganisms inhabit the active generation zone in the Nankai Trough, offshore Japan. Three sites from ODP Leg 190 have been evaluated, namely 1173, 1174 and 1177, drilled in nearly undeformed Quaternary and Tertiary sedimentary sequences seaward of the Nankai Trough itself. Paleotemperatures were reconstructed based on subsidence profiles, compaction modelling, present-day heat flow, downhole temperature measurements and organic maturity parameters. Today's heat flow distribution can be considered mainly conductive, and is extremely high in places, reaching 180 mW/m 2. The kinetic parameters describing total hydrocarbon generation, determined by laboratory pyrolysis experiments, were utilized by the model in order to predict the timing of generation in time and space. The model predicts that the onset of present day generation lies between 300 and 500 m below sea floor (5100-5300 m below mean sea level), depending on well location. In the case of Site 1174, 5-10% conversion has taken place by a present day temperature of ca. 85 °C. Predictions were largely validated by on-site hydrocarbon gas measurements. Viable organisms in the same depth range have been proven using 14C-radiolabelled substrates for methanogenesis, bacterial cell counts and intact phospholipids. Altogether, these results point to an overlap of abiotic thermal degradation reactions going on in the same part of the sedimentary column as where a deep biosphere exists. The organic matter preserved in Nankai Trough sediments is of the type that generates putative feedstocks for microbial activity, namely oxygenated compounds and hydrocarbons. Furthermore, the rates of thermal degradation calculated from the kinetic model closely resemble rates of respiration and electron donor consumption independently measured in other deep biosphere environments. We deduce that abiotically driven degradation reactions have provided substrates for microbial activity in deep sediments at this convergent continental margin.

The Study of Socio-Biospheric Problems.

ERIC Educational Resources Information Center

Scott, Andrew M.

Concepts, tools, and a methodology are needed which will permit the analysis of emergent socio-biospheric problems and facilitate their effective management. Many contemporary problems may be characterized as socio-biospheric; for example, pollution of the seas, acid rain, the growth of cities, and an atmosphere loaded with carcinogens. However,…

[The ways in which variations in space and atmospheric factors act upon the biosphere and humans].

PubMed

Chernogor, L F

2010-01-01

The system analysis is validated to be an efficient means for studying the channels through which variations in space and tropospheric weather affect the biosphere (humans). The basics of the system analysis paradigm are presented. The causes of variations in space and tropospheric weather are determined, and the interrelations between them are demonstrated. The ways in which these variations affect the biosphere (humans) are discussed. Aperiodic and quasi-periodic disturbances in the physical fields that influence the biosphere (humans) are intercompared.

Using remote-sensing and the Simple Biosphere model (SiB4) to analyze the seasonality and productivity of the terrestrial biosphere.

NASA Astrophysics Data System (ADS)

Cheeseman, M.; Denning, S.; Baker, I. T.

2017-12-01

Understanding the variability and seasonality of carbon fluxes from the terrestrial biosphere is integral to understanding the mechanisms and drivers of the global carbon cycle. However, there are many regions across the globe where in situ observations are sparse, such as the Amazon rainforest and the African Sahel. The latest version of the Simple-Biosphere model (SiB4) predicts a suite of biophysical variables such as terrestrial carbon flux (GPP), solar induced fluorescence (SIF), fraction of photosynthetically active radiation (FPAR), and leaf area index (LAI). By comparing modeled values to a suite of satellite and in situ observations we produce a robust analysis of the seasonality and productivity of the terrestrial biosphere in a variety of biome types across the globe.

The water cycle in closed ecological systems: Perspectives from the Biosphere 2 and Laboratory Biosphere systems

NASA Astrophysics Data System (ADS)

Nelson, Mark; Dempster, W. F.; Allen, J. P.

2009-12-01

To achieve sustainable, healthy closed ecological systems requires solutions to challenges of closing the water cycle - recycling wastewater/irrigation water/soil medium leachate and evaporated water and supplying water of required quality as needed for different needs within the facility. Engineering Biosphere 2, the first multi-biome closed ecological system within a total airtight footprint of 12,700 m 2 with a combined volume of 200,000 m 3 with a total water capacity of some 6 × 10 6 L of water was especially challenging because it included human inhabitants, their agricultural and technical systems, as well as five analogue ecosystems ranging from rainforest to desert, freshwater ecologies to saltwater systems like mangrove and mini-ocean coral reef ecosystems. By contrast, the Laboratory Biosphere - a small (40 m 3 volume) soil-based plant growth facility with a footprint of 15 m 2 - is a very simplified system, but with similar challenges re salinity management and provision of water quality suitable for plant growth. In Biosphere 2, water needs included supplying potable water for people and domestic animals, irrigation water for a wide variety of food crops, and recycling and recovering soil nutrients from wastewater. In the wilderness biomes, providing adequately low salinity freshwater terrestrial ecosystems and maintaining appropriate salinity and pH in aquatic/marine ecosystems were challenges. The largest reservoirs in Biosphere 2 were the ocean/marsh with some 4 × 10 6 L, soil with 1 to 2 × 10 6 l, primary storage tank with 0 to 8 × 10 5 L and storage tanks for condensate and soil leachate collection and mixing tanks with a capacity of 1.6 × 10 5 L to supply irrigation for farm and wilderness ecosystems. Other reservoirs were far smaller - humidity in the atmosphere (2 × 10 3 L), streams in the rainforest and savannah, and seasonal pools in the desert were orders of magnitude smaller (8 × 10 4 L). Key technologies included condensation from humidity in the air handlers and from the glass space frame to produce high quality freshwater, wastewater treatment with constructed wetlands and desalination through reverse osmosis and flash evaporation were key to recycling water with appropriate quality throughout the Biosphere 2 facility. Wastewater from all human uses and the domestic animals in Biosphere 2 was treated and recycled through a series of constructed wetlands, which had hydraulic loading of 0.9-1.1 m 3 day -1 (240-290 gal d -1). Plant production in the wetland treatment system produced 1210 kg dry weight of emergent and floating aquatic plant wetland which was used as fodder for the domestic animals while remaining nutrients/water was reused as part of the agricultural irrigation supply. There were pools of water with recycling times of days to weeks and others with far longer cycling times within Biosphere 2. By contrast, the Laboratory Biosphere with a total water reservoir of less than 500 L has far quicker cycling rapidity: for example, atmospheric residence time for water vapor was 5-20 min in the Laboratory Biosphere vs. 1-4 h in Biosphere 2, as compared with 9 days in the Earth's biosphere. Just as in Biosphere 2, humidity in the Laboratory Biosphere amounts to a very small reservoir of water. The amount of water passing through the air in the course of a 12-h operational day is two orders of magnitude greater than the amount stored in the air. Thus, evaporation and condensation collection are vital parts of the recycle system just as in Biosphere 2. The water cycle and sustainable water recycling in closed ecological systems presents problems requiring further research - such as how to control buildup of salinity in materially closed ecosystems and effective ways to retain nutrients in optimal quantity and useable form for plant growth. These issues are common to all closed ecological systems of whatever size, including planet Earth's biosphere and are relevant to a global environment facing increasing water shortages while maintaining water quality for human and ecosystem health. Modular biospheres offer a test bed where technical methods of resolving these problems can be tested for feasibility.

Governing Portable Conservation and Development Landscapes: Reconsidering Evidence in the Context of the Mbaracayú Biosphere Reserve

ERIC Educational Resources Information Center

Elgert, Laureen

2014-01-01

Conservation-with-development landscapes, such as UNESCO's Man and Biosphere Reserves, differentiate between areas of "nature" and "society". In Paraguay's Mbaracayú Biosphere Reserve, as elsewhere, this model has been used to support governance that focuses on conservation in the "core area" and sustainable…

Selection, management and utilization of biosphere reserves.

Treesearch

Jerry F. Franklin; Stanley L. Krugman

1979-01-01

This publication is directed to the analysis of the selection, management, and utilization of Biosphere Reserves as viewed by scientists from the United States and the Union of Soviet Socialist Republics. Soviet papers focus on types of research and monitoring programs that should be developed on Biosphere Reserves, with emphasis on their use in pollutant monitoring....

WEB-DHM: A distributed biosphere hydrological model developed by coupling a simple biosphere scheme with a hillslope hydrological model

USDA-ARS?s Scientific Manuscript database

The coupling of land surface models and hydrological models potentially improves the land surface representation, benefiting both the streamflow prediction capabilities as well as providing improved estimates of water and energy fluxes into the atmosphere. In this study, the simple biosphere model 2...

Life systems for a lunar base

NASA Technical Reports Server (NTRS)

Nelson, Mark; Hawes, Philip B.; Augustine, Margret

1992-01-01

The Biosphere 2 project is pioneering work on life systems that can serve as a prototype for long-term habitation on the Moon. This project will also facilitate the understanding of the smaller systems that will be needed for initial lunar base life-support functions. In its recommendation for a policy for the next 50 years in space, the National Commission on Space urged, 'To explore and settle the inner Solar System, we must develop biospheres of smaller size, and learn how to build and maintain them' (National Commission on Space, 1986). The Biosphere 2 project, along with its Biospheric Research and Development Center, is a materially closed and informationally and energetically open system capable of supporting a human crew of eight, undertaking work to meet this need. This paper gives an overview of the Space Biospheres Ventures' endeavor and its lunar applications.

Preliminary Feasibility Study of a Hybrid Solar and Modular Pumped Storage Hydro System at Biosphere 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lansey, Kevin; Hortsman, Chris

2016-10-01

In this study, the preliminary feasibility of a hybrid solar and modular pumped storage system designed for high energy independence at Biosphere 2 is assessed. The system consists of an array of solar PV panels that generate electricity during the day to power both Biosphere 2 and a pump that sends water through a pipe to a tank at a high elevation. When solar power is not available, the water is released back down the pipe towards a tank at a lower elevation, where it passes through a hydraulic water turbine to generate hydroelectricity to power Biosphere 2. The hybridmore » system is sized to generate and store enough energy to enable Biosphere 2 to operate without a grid interconnection on an average day.« less

Parameter transferability within homogeneous regions and comparisons with predictions from a priori parameters in the eastern United States

NASA Astrophysics Data System (ADS)

Chouaib, Wafa; Alila, Younes; Caldwell, Peter V.

2018-05-01

The need for predictions of flow time-series persists at ungauged catchments, motivating the research goals of our study. By means of the Sacramento model, this paper explores the use of parameter transfer within homogeneous regions of similar climate and flow characteristics and makes comparisons with predictions from a priori parameters. We assessed the performance using the Nash-Sutcliffe (NS), bias, mean monthly hydrograph and flow duration curve (FDC). The study was conducted on a large dataset of 73 catchments within the eastern US. Two approaches to the parameter transferability were developed and evaluated; (i) the within homogeneous region parameter transfer using one donor catchment specific to each region, (ii) the parameter transfer disregarding the geographical limits of homogeneous regions, where one donor catchment was common to all regions. Comparisons between both parameter transfers enabled to assess the gain in performance from the parameter regionalization and its respective constraints and limitations. The parameter transfer within homogeneous regions outperformed the a priori parameters and led to a decrease in bias and increase in efficiency reaching a median NS of 0.77 and a NS of 0.85 at individual catchments. The use of FDC revealed the effect of bias on the inaccuracy of prediction from parameter transfer. In one specific region, of mountainous and forested catchments, the prediction accuracy of the parameter transfer was less satisfactory and equivalent to a priori parameters. In this region, the parameter transfer from the outsider catchment provided the best performance; less-biased with smaller uncertainty in medium flow percentiles (40%-60%). The large disparity of energy conditions explained the lack of performance from parameter transfer in this region. Besides, the subsurface stormflow is predominant and there is a likelihood of lateral preferential flow, which according to its specific properties further explained the reduced efficiency. Testing the parameter transferability using criteria of similar climate and flow characteristics at ungauged catchments and comparisons with predictions from a priori parameters are a novelty. The ultimate limitations of both approaches are recognized and recommendations are made for future research.

Biosphere as a complex life-support system (LSS) for human civilization

NASA Astrophysics Data System (ADS)

Pechurkin, Nickolay

As a continuously growing link of the Biosphere, we should keep in mind that biotic cycles induced by flows of a solar energy are the source of Biosphere and ecosystems functioning. Our pressure on the Biosphere which is connected with biotic cycle’s alterations and damages is menacingly growing. There are innumerable examples of atmosphere, water and soil pollution. We have contaminated even Earth-Space orbits with different uncontrolled debris. Ecological Footprint (EF) is a proper quantitative measure of anthropogenic impact on the Biosphere and ecosystems functioning. The comparative dynamics of the United Nations’ Human Development Index (HDI) and Ecological Footprint (EF) is discussed in the paper. The main call of sustainable development of mankind: all humans can have opportunity to fulfill their lives without degrading the Biosphere. To support sustainability, we should make an effort to develop each nation and the mankind as a whole with a high HDI and with a low ecological footprint. It means: to have high level of HDI at low level of EF. But current tendency of economical and social development shows: the higher HDI, the bigger EF. EF of mankind is rising threateningly. Now actual pressure of the human civilization of our planet (2014) upon 60 % exceeds its potential possibilities (biological capacity, measured as the area of "global" green hectares). It means that now we require more than 1.5 planets of the Earth’s type for sustainable development. It leads to ecological incident in the scale of Biosphere. Our Biosphere is the large, multilevel, hierarchically organized system, and our civilization is only a part of it. This part is not central; it can disappear for ever, if we do not cope to be included in the Biosphere as a great complex system. An example of Krasnoyarsk region as a representative region with high level of industry and technological energy production is considered in the paper. This work was supported by the Russian Foundation for Basic Research, project number 13-06-00060.

Contamination of woody habitat soils around a former lead smelter in the North of France.

PubMed

Douay, F; Pruvot, C; Waterlot, C; Fritsch, C; Fourrier, H; Loriette, A; Bidar, G; Grand, C; de Vaufleury, A; Scheifler, R

2009-10-15

The contamination of the topsoil of 262 woody habitats around a former lead smelter in the North of France was assessed. In this urbanized and industrialized area, these kinds of habitats comprise of hedges, groves, small woods, anthropogenic creations and one large forest. Except for the latter, which is 3 km away, these woody habitat soils often present a high anthropization degree (a significant amount of pebbles and stones related to human activities) with a high metal contamination. In the studied woody habitat topsoils, Cd, Pb and Zn concentrations largely exceeded those of agricultural topsoils located in the same environmental context. Therefore, atmospheric emissions from the smelter are not the only cause of the high contamination of the woody habitat soils. This last one is related to the nature and the contamination level of deposit in relation with human activities (rubbles, slag, soils, etc). With regard to the results obtained with chemical extractions, the mobility of Cd, Pb and Zn in these soils is also greater than in agricultural soils. In the forest, pollutant solubility is increased by soil acidic pH. The variability of the physico-chemical parameters and the high metal contamination of the topsoils are the main characteristics of the woody habitats located around the former smelter. Although never taken into account during risk assessment, the disturbance of these environmental components could have important biogeochemical impacts (nutrients and metal cycles). Moreover, any modification of the soils' use could potentially cause mobilization and transfer of the pollutants to the biosphere. Six years after the closure of the smelter, and as social and economic pressures considerably increase in this area, the study of these peculiar ecosystems is necessary to understand and predict the bioavailability, transfer, bioaccumulation and effects of pollutants in food chains.

Spanish methodological approach for biosphere assessment of radioactive waste disposal.

PubMed

Agüero, A; Pinedo, P; Cancio, D; Simón, I; Moraleda, M; Pérez-Sánchez, D; Trueba, C

2007-10-01

The development of radioactive waste disposal facilities requires implementation of measures that will afford protection of human health and the environment over a specific temporal frame that depends on the characteristics of the wastes. The repository design is based on a multi-barrier system: (i) the near-field or engineered barrier, (ii) far-field or geological barrier and (iii) the biosphere system. Here, the focus is on the analysis of this last system, the biosphere. A description is provided of conceptual developments, methodological aspects and software tools used to develop the Biosphere Assessment Methodology in the context of high-level waste (HLW) disposal facilities in Spain. This methodology is based on the BIOMASS "Reference Biospheres Methodology" and provides a logical and systematic approach with supplementary documentation that helps to support the decisions necessary for model development. It follows a five-stage approach, such that a coherent biosphere system description and the corresponding conceptual, mathematical and numerical models can be built. A discussion on the improvements implemented through application of the methodology to case studies in international and national projects is included. Some facets of this methodological approach still require further consideration, principally an enhanced integration of climatology, geography and ecology into models considering evolution of the environment, some aspects of the interface between the geosphere and biosphere, and an accurate quantification of environmental change processes and rates.

Biospheric effects of a large extraterrestrial impact: Case study of the Cretaceous/Tertiary boundary crater

NASA Technical Reports Server (NTRS)

Pope, Kevin O.

1994-01-01

The Chicxulub Crater in Yucatan, Mexico, is the primary candidate for the impact that caused mass extinctions at the Cretaceous/Tertiary boundary. The target rocks at Chicxulub contain 750 to 1500 m of anhydrite (CaSO4), which was vaporized upon impact, creating a large sulfuric acid aerosol cloud. In this study we apply a hydrocode model of asteroid impact to calculate the amount of sulfuric acid produced. We then apply a radiative transfer model to determine the atmospheric effects. Results include 6 to 9 month period of darkness followed by 12 to 26 years of cooling.

Effects of Space Weather on Biomedical Parameters during the Solar Activity Cycles 23-24.

PubMed

Ragul'skaya, M V; Rudenchik, E A; Chibisov, S M; Gromozova, E N

2015-06-01

The results of long-term (1998-2012) biomedical monitoring of the biotropic effects of space weather are discussed. A drastic change in statistical distribution parameters in the middle of 2005 was revealed that did not conform to usual sinusoidal distribution of the biomedical data reflecting changes in the number of solar spots over a solar activity cycle. The dynamics of space weather of 2001-2012 is analyzed. The authors hypothesize that the actual change in statistical distributions corresponds to the adaptation reaction of the biosphere to nonstandard geophysical characteristics of the 24th solar activity cycle and the probable long-term decrease in solar activity up to 2067.

Man and the Biosphere: Ground Truthing Coral Reefs for the St. John Island Biosphere Reserve.

ERIC Educational Resources Information Center

Brody, Michael J.; And Others

Research on the coral species composition of St. John's reefs in the Virgin Islands was conducted through the School for Field Studies (SFS) Coral Reef Ecology course (winter 1984). A cooperative study program based on the United Nations Educational, Scientific, and Cultural Organization's (Unesco) program, Man and the Biosphere, was undertaken by…

Additional Research Needs to Support the GENII Biosphere Models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Napier, Bruce A.; Snyder, Sandra F.; Arimescu, Carmen

In the course of evaluating the current parameter needs for the GENII Version 2 code (Snyder et al. 2013), areas of possible improvement for both the data and the underlying models have been identified. As the data review was implemented, PNNL staff identified areas where the models can be improved both to accommodate the locally significant pathways identified and also to incorporate newer models. The areas are general data needs for the existing models and improved formulations for the pathway models.

Optical Measurements with Related Chemical, Biological, and Physical Parameters from the Central Equatorial Pacific Ocean: NOAA Ship Discoverer Cruise RP-9-DI-84

DTIC Science & Technology

1986-09-01

stations one and two, separate casts were made for Freon sampling and deep geochemistry sampling with either Freon syringes or 30-liter bottles. On...subsequent stations, deep geochemistry and Freon sampling were done on one cast. A separate cast for chlorophyll using 10-liter bottles on the Rosette...vertical to horizontal. The deck sensor used was a Biospherical Instruments, Inc., Solar Reference Hemispherical Irradiance Sensor which monitors the

Using the kingfisher (Alcedo atthis) as a bioindicator of PCBs and PBDEs in the dinghushan biosphere reserve, China.

PubMed

Mo, Ling; Wu, Jiang-Ping; Luo, Xiao-Jun; Li, Ke-Lin; Peng, Ying; Feng, An-Hong; Zhang, Qiang; Zou, Fa-Sheng; Mai, Bi-Xian

2013-07-01

The Dinghushan Biosphere Reserve is a nature reserve and a site for the study of tropical and subtropical forest ecosystems. Rapid industrialization and intensive electronic waste-recycling activities around the biosphere reserve have resulted in elevated levels of industrial organic contaminants in the local environment that may cause adverse effects on wildlife that inhabits this area. In the present study, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and 2 alternative brominated flame retardants (BFRs)-decabromodiphenyl ethane (DBDPE) and 1,2-bis(2,4,6-tribromophenoxy) ethane (BTBPE)-were investigated in the biosphere reserve and a reference site by using the kingfisher (Alcedo atthis) as a bioindicator. Residue concentrations in kingfishers from the Dinghushan Biosphere Reserve ranged from 490 ng/g to 3000 ng/g, 51 ng/g to 420 ng/g, 0.44 ng/g to 90 ng/g, and 0.04 ng/g to 0.87 ng/g lipid weight for ∑PCBs, ∑PBDEs, DBDPE, and BTBPE, respectively. With the exception of the BTBPE, these levels were 2 to 5 times higher than those detected in kingfishers from the reference site. The contaminant patterns from the biosphere reserve were also different, with larger PCB contributions in comparison with the reference site. The estimated predator-prey biomagnification factors (BMFs) showed that most of the PCB and PBDE congeners and BTBPE were biomagnified in kingfishers from the biosphere reserve. The calculated toxic equivalent quantity (TEQ) concentrations of major coplanar PCB congeners in kingfishers from the biosphere reserve ranged from 18 pg/g to 66 pg/g wet weight, with some of these TEQ concentrations reaching or exceeding the levels known to impair bird reproduction and survival. Copyright © 2013 SETAC.

The biosphere: Problems and solutions; Proceedings of the Miami International Symposium on the Biosphere, Miami Beach, FL, April 23, 24, 1984

NASA Astrophysics Data System (ADS)

Veziroglu, T. N.

The objective of the Miami International Symposium on the Biosphere was to provide a forum for the presentation of the latest research findings on the environmental effects of human activities. The topics discussed are related to biosphere reserves, environmental aspects of hydrocarbon fuels, radioactivity and nuclear waste, land management, acid rains, water quality, water resources, coastal resources management, the pollution of rivers, industrial waste, economic development and the environment, health hazards and solutions, endangered species, environmentally compatible systems, space pollution, and global considerations. Attention is given to questions regarding global security and sustainable development, environethics as a global strategy for environmental quality, a gestalt approach to the environment, potential indicators for monitoring biosphere reserves, a review of regional impacts associated with the development of U.S. synthetic fuel resources, water resources in the Soviet Union, and pollution-free pesticides.

Quantifying the Importance of the Rare Biosphere for Microbial Community Response to Organic Pollutants in a Freshwater Ecosystem

PubMed Central

Wang, Yuanqi; Hatt, Janet K.; Tsementzi, Despina; Rodriguez-R, Luis M.; Ruiz-Pérez, Carlos A.; Kizer, Heidi; Maresca, Gina; Krishnan, Raj; Poretsky, Rachel; Spain, Jim C.

2017-01-01

ABSTRACT A single liter of water contains hundreds, if not thousands, of bacterial and archaeal species, each of which typically makes up a very small fraction of the total microbial community (<0.1%), the so-called “rare biosphere.” How often, and via what mechanisms, e.g., clonal amplification versus horizontal gene transfer, the rare taxa and genes contribute to microbial community response to environmental perturbations represent important unanswered questions toward better understanding the value and modeling of microbial diversity. We tested whether rare species frequently responded to changing environmental conditions by establishing 20-liter planktonic mesocosms with water from Lake Lanier (Georgia, USA) and perturbing them with organic compounds that are rarely detected in the lake, including 2,4-dichlorophenoxyacetic acid (2,4-D), 4-nitrophenol (4-NP), and caffeine. The populations of the degraders of these compounds were initially below the detection limit of quantitative PCR (qPCR) or metagenomic sequencing methods, but they increased substantially in abundance after perturbation. Sequencing of several degraders (isolates) and time-series metagenomic data sets revealed distinct cooccurring alleles of degradation genes, frequently carried on transmissible plasmids, especially for the 2,4-D mesocosms, and distinct species dominating the post-enrichment microbial communities from each replicated mesocosm. This diversity of species and genes also underlies distinct degradation profiles among replicated mesocosms. Collectively, these results supported the hypothesis that the rare biosphere can serve as a genetic reservoir, which can be frequently missed by metagenomics but enables community response to changing environmental conditions caused by organic pollutants, and they provided insights into the size of the pool of rare genes and species. IMPORTANCE A single liter of water or gram of soil contains hundreds of low-abundance bacterial and archaeal species, the so called rare biosphere. The value of this astonishing biodiversity for ecosystem functioning remains poorly understood, primarily due to the fact that microbial community analysis frequently focuses on abundant organisms. Using a combination of culture-dependent and culture-independent (metagenomics) techniques, we showed that rare taxa and genes commonly contribute to the microbial community response to organic pollutants. Our findings should have implications for future studies that aim to study the role of rare species in environmental processes, including environmental bioremediation efforts of oil spills or other contaminants. PMID:28258138

Quantifying the Importance of the Rare Biosphere for Microbial Community Response to Organic Pollutants in a Freshwater Ecosystem.

PubMed

Wang, Yuanqi; Hatt, Janet K; Tsementzi, Despina; Rodriguez-R, Luis M; Ruiz-Pérez, Carlos A; Weigand, Michael R; Kizer, Heidi; Maresca, Gina; Krishnan, Raj; Poretsky, Rachel; Spain, Jim C; Konstantinidis, Konstantinos T

2017-04-15

A single liter of water contains hundreds, if not thousands, of bacterial and archaeal species, each of which typically makes up a very small fraction of the total microbial community (<0.1%), the so-called "rare biosphere." How often, and via what mechanisms, e.g., clonal amplification versus horizontal gene transfer, the rare taxa and genes contribute to microbial community response to environmental perturbations represent important unanswered questions toward better understanding the value and modeling of microbial diversity. We tested whether rare species frequently responded to changing environmental conditions by establishing 20-liter planktonic mesocosms with water from Lake Lanier (Georgia, USA) and perturbing them with organic compounds that are rarely detected in the lake, including 2,4-dichlorophenoxyacetic acid (2,4-D), 4-nitrophenol (4-NP), and caffeine. The populations of the degraders of these compounds were initially below the detection limit of quantitative PCR (qPCR) or metagenomic sequencing methods, but they increased substantially in abundance after perturbation. Sequencing of several degraders (isolates) and time-series metagenomic data sets revealed distinct cooccurring alleles of degradation genes, frequently carried on transmissible plasmids, especially for the 2,4-D mesocosms, and distinct species dominating the post-enrichment microbial communities from each replicated mesocosm. This diversity of species and genes also underlies distinct degradation profiles among replicated mesocosms. Collectively, these results supported the hypothesis that the rare biosphere can serve as a genetic reservoir, which can be frequently missed by metagenomics but enables community response to changing environmental conditions caused by organic pollutants, and they provided insights into the size of the pool of rare genes and species. IMPORTANCE A single liter of water or gram of soil contains hundreds of low-abundance bacterial and archaeal species, the so called rare biosphere. The value of this astonishing biodiversity for ecosystem functioning remains poorly understood, primarily due to the fact that microbial community analysis frequently focuses on abundant organisms. Using a combination of culture-dependent and culture-independent (metagenomics) techniques, we showed that rare taxa and genes commonly contribute to the microbial community response to organic pollutants. Our findings should have implications for future studies that aim to study the role of rare species in environmental processes, including environmental bioremediation efforts of oil spills or other contaminants. Copyright © 2017 American Society for Microbiology.

Atmospheric redistribution of reactive nitrogen and phosphorus by wildfires and implications for global carbon cycling

NASA Astrophysics Data System (ADS)

Randerson, J. T.; Xu, L.; Wiggins, E. B.; Chen, Y.; Riley, W. J.; Mekonnen, Z. A.; Pellegrini, A.; Mahowald, N. M.

2017-12-01

Fires are an important process regulating the redistribution of nutrients within terrestrial ecosystems. Frequently burning ecosystems such as savannas are a net source of N and P to the atmosphere each year, with atmospheric transport and dry and wet deposition increasing nutrient availability in downwind ecosystems and over the open ocean. Transport of N and P aerosols from savanna fires within the Hadley circulation contributes to nutrient deposition over tropical forests, yielding an important cross-biome nutrient transfer. Pyrodenitrification of reactive N increases with fire temperature and modified combustion efficiency, generating a global net biospheric loss of approximately 14 Tg N per year. Here we analyze atmospheric N and P redistribution using the Global Fire Emissions Database version 4s and the Accelerated Climate Modeling for Energy earth system model. We synthesize literature estimates of N and P concentrations in fire-emitted aerosols and ecosystem mass balance measurements to help constrain model estimates of these biosphere-atmosphere fluxes. In our analysis, we estimate the fraction of terrestrial net primary production (NPP) that is sustained by fire-emitted P and reactive N from upwind ecosystems. We then evaluate how recent global declines in burned area in savanna and grassland ecosystems may be changing nutrient availability in downwind ecosystems.

The Biosphere: A Decadal Vision

NASA Technical Reports Server (NTRS)

Peterson, David L.; Curran, Paul J.; Mlynzcak, Marty; Miller, Richard

2003-01-01

This paper focuses on biosphere-climate interactions including the influences of human activities. Recognizing this is only one aspect of biospheric processes, this places an emphasis of those biogeochemical processes that have a profound effect on numerous other aspects of the biosphere and the services it provides, services which are critical to sustaining life on Earth. And, the paper will focus on the various scientific aspects of assessing the availability of fresh water, including its sensitivity to climate variance and land use changes. Finally, this paper hopes to emphasize the potential role that greatly expanded space observations and interactive modeling can play in developing our understanding of Earth and its the living systems.

Biosphere 2 test module experimentation program

NASA Technical Reports Server (NTRS)

Alling, Abigail; Leigh, Linda S.; Maccallum, Taber; Alvarez-Romo, Norberto

1990-01-01

The Biosphere 2 Test Module is a facility which has the capability to do either short or long term closures: five month closures with plants were conducted. Also conducted were investigations of specific problems, such as trace gas purification by bioregenerative systems by in-putting a fixed concentration of a gas and observing its uptake over time. In other Test Module experiments, the concentration of one gas was changed to observe what effects this has on other gases present or on the system. The science of biospherics which encompasses the study of closed biological systems provides an opening into the future in space as well as in the Earth's biosphere.

Rarity in aquatic microbes: placing protists on the map.

PubMed

Logares, Ramiro; Mangot, Jean-François; Massana, Ramon

2015-12-01

Most microbial richness at any given time tends to be represented by low-abundance (rare) taxa, which are collectively referred to as the "rare biosphere". Here we review works on the rare biosphere using high-throughput sequencing (HTS), with a particular focus on unicellular eukaryotes or protists. Evidence thus far indicates that the rare biosphere encompasses dormant as well as metabolically active microbes that could potentially play key roles in ecosystem functioning. Rare microbes appear to have biogeography, and sometimes the observed patterns can be similar to what is observed among abundant taxa, suggesting similar community-structuring mechanisms. There is limited evidence indicating that the rare biosphere contains taxa that are phylogenetically distantly related to abundant counterparts; therefore, the rare biosphere may act as a reservoir of deep-branching phylogenetic diversity. The potential role of the rare biosphere as a bank of redundant functions that can help to maintain continuous ecosystem function following oscillations in taxonomic abundances is hypothesized as its main ecological role. Future studies focusing on rare microbes are crucial for advancing our knowledge of microbial ecology and evolution and unveiling their links with ecosystem function. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Opportunities and challenges in studies of deep life (Invited)

NASA Astrophysics Data System (ADS)

Edwards, K. J.

2010-12-01

Over the past two decades, there has been an increasing awareness within the geological, microbiological, and oceanographic communities of the potentially vast microbial biosphere that is harbored beneath the surface of the Earth. With this awareness has come a mounting effort to study this potential biome - to better quantify biomass abundance, activity, and biogeochemical activity. In the Earth system, the largest deep subsurface biome is also the least accessible - the deep ocean subsurface biosphere. The oceanic deep biosphere also has greatest potential for influencing global scale biogeochemical processes -the carbon and energy cycles for example, and other elemental cycles. To address these topics and mount interdisciplinary efforts to study the deep subsurface marine biosphere, we have recently formed a center in support integrative, collaborative investigations. The national science foundation Center for Dark Biosphere Investigations (C-DEBI), has been initiated for the explicit purpose of resolving the extent, function, dynamics and implications of the subseafloor biosphere. This talk will discuss C-DEBI science, with focus on some of the opportunities and challenges in the study of deep life in the ocean, and the role that C-DEBI will play in meeting them

Preindustrial nitrous oxide emissions from the land biosphere estimated by using a global biogeochemistry model

NASA Astrophysics Data System (ADS)

Xu, Rongting; Tian, Hanqin; Lu, Chaoqun; Pan, Shufen; Chen, Jian; Yang, Jia; Zhang, Bowen

2017-07-01

To accurately assess how increased global nitrous oxide (N2O) emission has affected the climate system requires a robust estimation of the preindustrial N2O emissions since only the difference between current and preindustrial emissions represents net drivers of anthropogenic climate change. However, large uncertainty exists in previous estimates of preindustrial N2O emissions from the land biosphere, while preindustrial N2O emissions on the finer scales, such as regional, biome, or sector scales, have not been well quantified yet. In this study, we applied a process-based Dynamic Land Ecosystem Model (DLEM) to estimate the magnitude and spatial patterns of preindustrial N2O fluxes at the biome, continental, and global level as driven by multiple environmental factors. Uncertainties associated with key parameters were also evaluated. Our study indicates that the mean of the preindustrial N2O emission was approximately 6.20 Tg N yr-1, with an uncertainty range of 4.76 to 8.13 Tg N yr-1. The estimated N2O emission varied significantly at spatial and biome levels. South America, Africa, and Southern Asia accounted for 34.12, 23.85, and 18.93 %, respectively, together contributing 76.90 % of global total emission. The tropics were identified as the major source of N2O released into the atmosphere, accounting for 64.66 % of the total emission. Our multi-scale estimates provide a robust reference for assessing the climate forcing of anthropogenic N2O emission from the land biosphere

The Earth's Biosphere

NASA Technical Reports Server (NTRS)

2002-01-01

In the last five years, scientists have been able to monitor our changing planet in ways never before possible. The Sea-viewing Wide Field-of-View Sensor (SeaWiFS), aboard the OrbView-2 satellite, has given researchers an unprecedented view of the biological engine that drives life on Earth-the countless forms of plants that cover the land and fill the oceans. 'There is no question the Earth is changing. SeaWiFS has enabled us, for the first time, to monitor the biological consequences of that change-to see how the things we do, as well as natural variability, affect the Earth's ability to support life,' said Gene Carl Feldman, SeaWiFS project manager at NASA's Goddard Space Flight Center, Greenbelt, Md. SeaWiFS data, based on continuous daily global observations, have helped scientists make a more accurate assessment of the oceans' role in the global carbon cycle. The data provide a key parameter in a number of ecological and environmental studies as well as global climate-change modeling. The images of the Earth's changing land, ocean and atmosphere from SeaWiFS have documented many previously unrecognized phenomena. The image above shows the global biosphere from June 2002 measured by SeaWiFS. Data in the oceans is chlorophyll concentration, a measure of the amount of phytoplankton (microscopic plants) living in the ocean. On land SeaWiFS measures Normalized Difference Vegetation Index, an indication of the density of plant growth. For more information and images, read: SeaWiFS Sensor Marks Five Years Documenting Earth'S Dynamic Biosphere Image courtesy SeaWiFS project and copyright Orbimage.

Climate regulates the erosional carbon export from the terrestrial biosphere

NASA Astrophysics Data System (ADS)

Hilton, Robert G.

2017-01-01

Erosion drives the export of particulate organic carbon from the terrestrial biosphere (POCbiosphere) and its delivery to rivers. The carbon transfer is globally significant and can result in drawdown of atmospheric carbon dioxide (CO2) if the eroded POCbiosphere escapes degradation during river transfer and sedimentary deposition. Despite this recognition, we lack a global perspective on how the tectonic and climatic factors which govern physical erosion regulate POCbiosphere discharge, obscuring linkages between mountain building, climate, and CO2 drawdown. To fill this deficit, geochemical (δ13C, 14C and C/N), hydrometric (water discharge, suspended sediment concentration) and geomorphic (slope) measurements are combined from 33 globally-distributed forested mountain catchments. Radiocarbon activity is used to account for rock-derived organic carbon and reveals that POCbiosphere eroded from mountain forests is mostly < 1300 14C years old. Annual POCbiosphere yields are positively correlated with suspended sediment yields, confirming results from Taiwan and a recent global analysis, and are high in catchments with the steepest slopes. Based on these relationships and the global distribution of slope angles (3-arc-second), it is suggested that topography steeper than 10° (16% of the continental area) may contribute 40% of global POCbiosphere erosional flux. Climate is shown to regulate POCbiosphere discharge by mountain rivers, by controlling hydrologically-driven erosion processes. In catchments where discharge measurements are available (8 of the 33) a significant relationship exists between daily runoff (mm day- 1) and POCbiosphere concentration (mg L- 1) (r = 0.53, P < 0.0001). The relationship can be described by a single power law and suggests a high connectivity between forested hillslopes and mountain river channels. As a result, annual POCbiosphere yields are significantly correlated with mean annual runoff (r = 0.64, P < 0.0001). A shear-stress POCbiosphere erosion model is proposed which can explain the patterns in the data. The model allows the climate sensitivity of this carbon flux to be assessed for the first time. For a 1% increase in annual runoff, POCbiosphere discharge is predicted to increase by 4%. In steeper catchments, POCbiosphere discharge increases more rapidly with an increase in annual runoff. For comparison, a 1% increase in annual runoff is predicted to increase carbon transfers by silicate weathering solute fluxes in mountains by 0.4-0.7%. Depending on the fate of the eroded POCbiosphere, river export of POCbiosphere from mountains may act as an important negative feedback on rising atmospheric CO2 and increased global temperature. Erosion of carbon from the terrestrial biosphere links mountain building and climate to the geological evolution of atmospheric CO2, while the carbon fluxes are sensitive to predicted changes in runoff over the coming century. Supplementary Table 2 - Global forested mountain river catchments with estimates of suspended sediment and POCbiosphere, and POCpetro yields, and annual runoff. Supplementary Table 3 - Geomorphic characteristics of mountain river catchments. Supplementary Table 4 - Outputs of binary mixing model.

Response of the rare biosphere to environmental stressors in a highly diverse ecosystem (Zodletone spring, OK, USA).

PubMed

Coveley, Suzanne; Elshahed, Mostafa S; Youssef, Noha H

2015-01-01

Within highly diverse ecosystems, the majority of bacterial taxa are present in low abundance as members of the rare biosphere. The rationale for the occurrence and maintenance of the rare biosphere, and the putative ecological role(s) and dynamics of its members within a specific ecosystem is currently debated. We hypothesized that in highly diverse ecosystems, a fraction of the rare biosphere acts as a backup system that readily responds to environmental disturbances. We tested this hypothesis by subjecting sediments from Zodletone spring, a sulfide- and sulfur-rich spring in Southwestern OK, to incremental levels of salinity (1, 2, 3, 4, and 10% NaCl), or temperature (28°, 30°, 32°, and 70 °C), and traced the trajectories of rare members of the community in response to these manipulations using 16S rRNA gene analysis. Our results indicate that multiple rare bacterial taxa are promoted from rare to abundant members of the community following such manipulations and that, in general, the magnitude of such recruitment is directly proportional to the severity of the applied manipulation. Rare members that are phylogenetically distinct from abundant taxa in the original sample (unique rare biosphere) played a more important role in the microbial community response to environmental disturbances, compared to rare members that are phylogenetically similar to abundant taxa in the original sample (non-unique rare biosphere). The results emphasize the dynamic nature of the rare biosphere, and highlight its complexity and non-monolithic nature.

A regional high-resolution carbon flux inversion of North America for 2004

NASA Astrophysics Data System (ADS)

Schuh, A. E.; Denning, A. S.; Corbin, K. D.; Baker, I. T.; Uliasz, M.; Parazoo, N.; Andrews, A. E.; Worthy, D. E. J.

2010-05-01

Resolving the discrepancies between NEE estimates based upon (1) ground studies and (2) atmospheric inversion results, demands increasingly sophisticated techniques. In this paper we present a high-resolution inversion based upon a regional meteorology model (RAMS) and an underlying biosphere (SiB3) model, both running on an identical 40 km grid over most of North America. Current operational systems like CarbonTracker as well as many previous global inversions including the Transcom suite of inversions have utilized inversion regions formed by collapsing biome-similar grid cells into larger aggregated regions. An extreme example of this might be where corrections to NEE imposed on forested regions on the east coast of the United States might be the same as that imposed on forests on the west coast of the United States while, in reality, there likely exist subtle differences in the two areas, both natural and anthropogenic. Our current inversion framework utilizes a combination of previously employed inversion techniques while allowing carbon flux corrections to be biome independent. Temporally and spatially high-resolution results utilizing biome-independent corrections provide insight into carbon dynamics in North America. In particular, we analyze hourly CO2 mixing ratio data from a sparse network of eight towers in North America for 2004. A prior estimate of carbon fluxes due to Gross Primary Productivity (GPP) and Ecosystem Respiration (ER) is constructed from the SiB3 biosphere model on a 40 km grid. A combination of transport from the RAMS and the Parameterized Chemical Transport Model (PCTM) models is used to forge a connection between upwind biosphere fluxes and downwind observed CO2 mixing ratio data. A Kalman filter procedure is used to estimate weekly corrections to biosphere fluxes based upon observed CO2. RMSE-weighted annual NEE estimates, over an ensemble of potential inversion parameter sets, show a mean estimate 0.57 Pg/yr sink in North America. We perform the inversion with two independently derived boundary inflow conditions and calculate jackknife-based statistics to test the robustness of the model results. We then compare final results to estimates obtained from the CarbonTracker inversion system and at the Southern Great Plains flux site. Results are promising, showing the ability to correct carbon fluxes from the biosphere models over annual and seasonal time scales, as well as over the different GPP and ER components. Additionally, the correlation of an estimated sink of carbon in the South Central United States with regional anomalously high precipitation in an area of managed agricultural and forest lands provides interesting hypotheses for future work.

Detecting Biosphere anomalies hotspots

NASA Astrophysics Data System (ADS)

Guanche-Garcia, Yanira; Mahecha, Miguel; Flach, Milan; Denzler, Joachim

2017-04-01

The current amount of satellite remote sensing measurements available allow for applying data-driven methods to investigate environmental processes. The detection of anomalies or abnormal events is crucial to monitor the Earth system and to analyze their impacts on ecosystems and society. By means of a combination of statistical methods, this study proposes an intuitive and efficient methodology to detect those areas that present hotspots of anomalies, i.e. higher levels of abnormal or extreme events or more severe phases during our historical records. Biosphere variables from a preliminary version of the Earth System Data Cube developed within the CAB-LAB project (http://earthsystemdatacube.net/) have been used in this study. This database comprises several atmosphere and biosphere variables expanding 11 years (2001-2011) with 8-day of temporal resolution and 0.25° of global spatial resolution. In this study, we have used 10 variables that measure the biosphere. The methodology applied to detect abnormal events follows the intuitive idea that anomalies are assumed to be time steps that are not well represented by a previously estimated statistical model [1].We combine the use of Autoregressive Moving Average (ARMA) models with a distance metric like Mahalanobis distance to detect abnormal events in multiple biosphere variables. In a first step we pre-treat the variables by removing the seasonality and normalizing them locally (μ=0,σ=1). Additionally we have regionalized the area of study into subregions of similar climate conditions, by using the Köppen climate classification. For each climate region and variable we have selected the best ARMA parameters by means of a Bayesian Criteria. Then we have obtained the residuals by comparing the fitted models with the original data. To detect the extreme residuals from the 10 variables, we have computed the Mahalanobis distance to the data's mean (Hotelling's T^2), which considers the covariance matrix of the joint distribution. The proposed methodology has been applied to different areas around the globe. The results show that the method is able to detect historic events and also provides a useful tool to define sensitive regions. This method and results have been developed within the framework of the project BACI (http://baci-h2020.eu/), which aims to integrate Earth Observation data to monitor the earth system and assessing the impacts of terrestrial changes. [1] V. Chandola, A., Banerjee and v., Kumar. Anomaly detection: a survey. ACM computing surveys (CSUR), vol. 41, n. 3, 2009. [2] P. Mahalanobis. On the generalised distance in statistics. Proceedings National Institute of Science, vol. 2, pp 49-55, 1936.

Access: A Directory of Contacts, Environmental Data Bases, and Scientific Infrastructure on 175 Biosphere Reserves in 32 Countries.

ERIC Educational Resources Information Center

Department of State, Washington, DC. Bureau of Oceans and International Environmental and Scientific Affairs.

Following the EuroMAB meeting in Strasbourg, France (September 1991) and on an initiative of the Man and the Biosphere National Committee of the United States, a decision was made to create a research network from information available in biosphere reserves in 30 European countries, Canada and the United States. This Directory of EuroMAB Biosphere…

Assessing the Importance of Prior Biospheric Fluxes on Inverse Model Estimates of CO2

NASA Astrophysics Data System (ADS)

Philip, S.; Johnson, M. S.; Potter, C. S.; Genovese, V. B.

2017-12-01

Atmospheric mixing ratios of carbon dioxide (CO2) are largely controlled by anthropogenic emissions and biospheric sources/sinks. The processes controlling terrestrial biosphere-atmosphere carbon exchange are currently not fully understood, resulting in models having significant differences in the quantification of biospheric CO2 fluxes. Currently, atmospheric chemical transport models (CTM) and global climate models (GCM) use multiple different biospheric CO2 flux models resulting in large differences in simulating the global carbon cycle. The Orbiting Carbon Observatory 2 (OCO-2) satellite mission was designed to allow for the improved understanding of the processes involved in the exchange of carbon between terrestrial ecosystems and the atmosphere, and therefore allowing for more accurate assessment of the seasonal/inter-annual variability of CO2. OCO-2 provides much-needed CO2 observations in data-limited regions allowing for the evaluation of model simulations of greenhouse gases (GHG) and facilitating global/regional estimates of "top-down" CO2 fluxes. We conduct a 4-D Variation (4D-Var) data assimilation with the GEOS-Chem (Goddard Earth Observation System-Chemistry) CTM using 1) OCO-2 land nadir and land glint retrievals and 2) global in situ surface flask observations to constrain biospheric CO2 fluxes. We apply different state-of-the-science year-specific CO2 flux models (e.g., NASA-CASA (NASA-Carnegie Ames Stanford Approach), CASA-GFED (Global Fire Emissions Database), Simple Biosphere Model version 4 (SiB-4), and LPJ (Lund-Postdam-Jena)) to assess the impact of "a priori" flux predictions to "a posteriori" estimates. We will present the "top-down" CO2 flux estimates for the year 2015 using OCO-2 and in situ observations, and a complete indirect evaluation of the a priori and a posteriori flux estimates using independent in situ observations. We will also present our assessment of the variability of "top-down" CO2 flux estimates when using different biospheric CO2 flux models. This work will improve our understanding of the global carbon cycle, specifically, how OCO-2 observations can be used to constrain biospheric CO2 flux model estimates.

An Estimate of the Total DNA in the Biosphere

PubMed Central

Landenmark, Hanna K. E.; Forgan, Duncan H.; Cockell, Charles S.

2015-01-01

Modern whole-organism genome analysis, in combination with biomass estimates, allows us to estimate a lower bound on the total information content in the biosphere: 5.3 × 1031 (±3.6 × 1031) megabases (Mb) of DNA. Given conservative estimates regarding DNA transcription rates, this information content suggests biosphere processing speeds exceeding yottaNOPS values (1024 Nucleotide Operations Per Second). Although prokaryotes evolved at least 3 billion years before plants and animals, we find that the information content of prokaryotes is similar to plants and animals at the present day. This information-based approach offers a new way to quantify anthropogenic and natural processes in the biosphere and its information diversity over time. PMID:26066900

An Estimate of the Total DNA in the Biosphere.

PubMed

Landenmark, Hanna K E; Forgan, Duncan H; Cockell, Charles S

2015-06-01

Modern whole-organism genome analysis, in combination with biomass estimates, allows us to estimate a lower bound on the total information content in the biosphere: 5.3 × 1031 (±3.6 × 1031) megabases (Mb) of DNA. Given conservative estimates regarding DNA transcription rates, this information content suggests biosphere processing speeds exceeding yottaNOPS values (1024 Nucleotide Operations Per Second). Although prokaryotes evolved at least 3 billion years before plants and animals, we find that the information content of prokaryotes is similar to plants and animals at the present day. This information-based approach offers a new way to quantify anthropogenic and natural processes in the biosphere and its information diversity over time.

The Effects of Decomposition on the Oxidative Ratio and Carbon Oxidation State of Organic Matter

NASA Astrophysics Data System (ADS)

Gallagher, M. E.; Masiello, C. A.; Clark, N.; Randerson, J. T.; Robertson, G. P.

2006-12-01

Ecosystem oxidative ratio (OR) and the related parameter carbon oxidation state (Cox) are critical in the apportionment of anthropogenic CO2 between the terrestrial biosphere and ocean reservoirs. OR is the ratio of O2 to CO2 in gas exchange fluxes between the biosphere and the atmosphere (Fba and Fab). Accurate measurements of OR have been challenging (Seibt et al. 2004); instead we approach the problem by measuring Cox and calculating OR from biomass reservoirs. Cox can range from -4 to +4 (CH4 to CO2) and is driven by photosynthesis, respiration, and decomposition. The net OR of the biosphere varies with ecosystem type, and this can affect the apportionment of anthropogenic CO2 between the terrestrial biosphere and ocean reservoirs (Randerson et al. 2006). This makes it essential to constrain ecosystem Cox and OR values. Although small variations in global ecosystem OR have the potential to cause shifts in atmospheric O2 concentrations, no whole ecosystem measurements of Cox yet exist. To constrain ORba and ORab, and improve our understanding of how decomposition affects Cox, we performed a litter bag experiment at the Kellogg Biological Station-Long Term Ecological Research (KBS-LTER) in Michigan at the end of the 2005 agricultural season. We placed 15 corn biomass litter bags in an agricultural field and collected 3 bags at 2, 4, 7, 26, and 29 weeks. These samples were analyzed for %C, %H, %N, and %O via elemental analysis, and these data were used to calculate Cox. Aboveground Cox was measured similarly. We anticipated that the Cox of the corn litter would become more reduced with decomposition, as the percentage of carbohydrates would decrease with time, while that of protein, lignin, and lipids would increase (Baldock et al. 2004). We report differences between the Cox of biomass fixation and biomass degradation from our experiments. Using simple assumptions about ecosystem nitrogen cycling, we convert Cox to OR and report the existence or absence of a temporal offset between ORab and ORba within an agricultural ecosystem.

Rewiring food systems to enhance human health and biosphere stewardship

NASA Astrophysics Data System (ADS)

Gordon, Line J.; Bignet, Victoria; Crona, Beatrice; Henriksson, Patrik J. G.; Van Holt, Tracy; Jonell, Malin; Lindahl, Therese; Troell, Max; Barthel, Stephan; Deutsch, Lisa; Folke, Carl; Jamila Haider, L.; Rockström, Johan; Queiroz, Cibele

2017-10-01

Food lies at the heart of both health and sustainability challenges. We use a social-ecological framework to illustrate how major changes to the volume, nutrition and safety of food systems between 1961 and today impact health and sustainability. These changes have almost halved undernutrition while doubling the proportion who are overweight. They have also resulted in reduced resilience of the biosphere, pushing four out of six analysed planetary boundaries across the safe operating space of the biosphere. Our analysis further illustrates that consumers and producers have become more distant from one another, with substantial power consolidated within a small group of key actors. Solutions include a shift from a volume-focused production system to focus on quality, nutrition, resource use efficiency, and reduced antimicrobial use. To achieve this, we need to rewire food systems in ways that enhance transparency between producers and consumers, mobilize key actors to become biosphere stewards, and re-connect people to the biosphere.

Response of the rare biosphere to environmental stressors in a highly diverse ecosystem (Zodletone spring, OK, USA)

PubMed Central

Coveley, Suzanne; Elshahed, Mostafa S.

2015-01-01

Within highly diverse ecosystems, the majority of bacterial taxa are present in low abundance as members of the rare biosphere. The rationale for the occurrence and maintenance of the rare biosphere, and the putative ecological role(s) and dynamics of its members within a specific ecosystem is currently debated. We hypothesized that in highly diverse ecosystems, a fraction of the rare biosphere acts as a backup system that readily responds to environmental disturbances. We tested this hypothesis by subjecting sediments from Zodletone spring, a sulfide- and sulfur-rich spring in Southwestern OK, to incremental levels of salinity (1, 2, 3, 4, and 10% NaCl), or temperature (28°, 30°, 32°, and 70 °C), and traced the trajectories of rare members of the community in response to these manipulations using 16S rRNA gene analysis. Our results indicate that multiple rare bacterial taxa are promoted from rare to abundant members of the community following such manipulations and that, in general, the magnitude of such recruitment is directly proportional to the severity of the applied manipulation. Rare members that are phylogenetically distinct from abundant taxa in the original sample (unique rare biosphere) played a more important role in the microbial community response to environmental disturbances, compared to rare members that are phylogenetically similar to abundant taxa in the original sample (non-unique rare biosphere). The results emphasize the dynamic nature of the rare biosphere, and highlight its complexity and non-monolithic nature. PMID:26312178

Comparing Amazon Basin CO2 fluxes from an atmospheric inversion with TRENDY biosphere models

NASA Astrophysics Data System (ADS)

Diffenbaugh, N. S.; Alden, C. B.; Harper, A. B.; Ahlström, A.; Touma, D. E.; Miller, J. B.; Gatti, L. V.; Gloor, M.

2015-12-01

Net exchange of carbon dioxide (CO2) between the atmosphere and the terrestrial biosphere is sensitive to environmental conditions, including extreme heat and drought. Of particular importance for local and global carbon balance and climate are the expansive tracts of tropical rainforest located in the Amazon Basin. Because of the Basin's size and ecological heterogeneity, net biosphere CO2 exchange with the atmosphere remains largely un-constrained. In particular, the response of net CO2 exchange to changes in environmental conditions such as temperature and precipitation are not yet well known. However, proper representation of these relationships in biosphere models is a necessary constraint for accurately modeling future climate and climate-carbon cycle feedbacks. In an effort to compare biosphere response to climate across different biosphere models, the TRENDY model intercomparison project coordinated the simulation of CO2 fluxes between the biosphere and atmosphere, in response to historical climate forcing, by 9 different Dynamic Global Vegetation Models. We examine the TRENDY model results in the Amazon Basin, and compare this "bottom-up" method with fluxes derived from a "top-down" approach to estimating net CO2 fluxes, obtained through atmospheric inverse modeling using CO2 measurements sampled by aircraft above the basin. We compare the "bottom-up" and "top-down" fluxes in 5 sub-regions of the Amazon basin on a monthly basis for 2010-2012. Our results show important periods of agreement between some models in the TRENDY suite and atmospheric inverse model results, notably the simulation of increased biosphere CO2 loss during wet season heat in the Central Amazon. During the dry season, however, model ability to simulate observed response of net CO2 exchange to drought was varied, with few models able to reproduce the "top-down" inversion flux signals. Our results highlight the value of atmospheric trace gas observations for helping to narrow the possibilities of future carbon-climate interactions, especially in historically under-observed regions like the Amazon.

Simulating Energy, Water and Carbon Fluxes at the Shortgrass Steppe Long Term Ecological Research (LTER) Site

NASA Astrophysics Data System (ADS)

Beltran-Przekurat, A. B.; Pielke, R. A.; Morgan, J. A.; Burke, I. C.

2005-12-01

Coupled atmospheric-biospheric models are a particularly valuable tool for studying the potential effects of land-use and land-cover changes on the near-surface atmosphere since the atmosphere and biosphere are allowed to dynamically interact through the surface and canopy energy balance. GEMRAMS is a coupled atmospheric-biospheric model comprised of an atmospheric model, RAMS, and an ecophysiological process-based model, GEMTM. In the first part of this study, the soil-vegetation-atmosphere-transfer (SVAT) scheme, LEAF2, from RAMS, coupled with GEMTM, are used to simulate energy, water and carbon fluxes over different cropping systems (winter wheat and irrigated corn) and over a mixed C3/C4 shortgrass prairie located at the USDA-ARS Central Plains Experimental Range near Nunn, Colorado, the LTER Shortgrass Steppe site. The new SVAT scheme, GEMLEAF, is forced with air temperature and humidity, wind speed and photosynthetic active radiation (PAR). Calculated canopy temperature and relative humidity, soil moisture and temperature and PAR are used to compute sunlit/shaded leaf photosynthesis (for C3 and C4 plant types) and respiration. Photosynthate is allocated to leaves, shoots, roots and reproductive organs with variable partition coefficients, which are functions of soil water conditions. As water stress increases, the fraction of photosynthate allocated to root growth increases. Leaf area index (LAI) is estimated from daily leaf biomass growth, using the vegetation-prescribed specific leaf area. Canopy conductance, computed and based on photosynthesis and relative humidity, is used to calculate latent heat flux. Simulated energy and CO2 fluxes are compared to observations collected using Bowen ratio flux towers during two growing seasons. Seasonality of the fluxes reflecting different plant phenologies agrees well with the observed patterns. In the second part of this study, simulations for two clear days are performed with GEMRAMS over a model domain centered at the SGS site. Simulated spatial differences in the energy fluxes can be associated with the highly heterogeneous landscape in this area.

Piezophilic Bacteria Isolated from Sediment of the Shimokita Coalbed, Japan

NASA Astrophysics Data System (ADS)

Fang, J.; Kato, C.; Hori, T.; Morono, Y.; Inagaki, F.

2013-12-01

The Earth is a cold planet as well as pressured planet, hosting both the surface biosphere and the deep biosphere. Pressure ranges over four-orders of magnitude in the surface biosphere and probably more in the deep biosphere. Pressure is an important thermodynamic property of the deep biosphere that affects microbial physiology and biochemistry. Bacteria that require high-pressure conditions for optimal growth are called piezophilic bacteria. Subseafloor marine sediments are one of the most extensive microbial habitats on Earth. Marine sediments cover more than two-thirds of the Earth's surface, and represent a major part of the deep biosphere. Owing to its vast size and intimate connection with the surface biosphere, particularly the oceans, the deep biosphere has enormous potential for influencing global-scale biogeochemical processes, including energy, climate, carbon and nutrient cycles. Therefore, studying piezophilic bacteria of the deep biosphere has important implications in increasing our understanding of global biogeochemical cycles, the interactions between the biosphere and the geosphere, and the evolution of life. Sediment samples were obtained during IODP Expedition 337, from 1498 meters below sea floor (mbsf) (Sample 6R-3), 1951~1999 mbsf (19R-1~25R-3; coalbed mix), and 2406 mbsf (29R-7). The samples were mixed with MB2216 growth medium and cultivated under anaerobic conditions at 35 MPa (megapascal) pressure. Growth temperatures were adjusted to in situ environmental conditions, 35°C for 6R-3, 45°C for 19R-1~25R-3, and 55°C for 29R-7. The cultivation was performed three times, for 30 days each time. Microbial cells were obtained and the total DNA was extracted. At the same time, isolation of microbes was also performed under anaerobic conditions. Microbial communities in the coalbed sediment were analyzed by cloning, sequencing, and terminal restriction fragment length polymorphism (t-RFLP) of 16S ribosomal RNA genes. From the partial 16S rRNA gene sequences, we have identified abundant Alkalibacterium sp. in 6R-3 and 29R-7 at the first HP cultivation. We also identified Haloactibacillus sp. in 6R-3 and Anoxybacillus related sp. in 19R-1~25R-3 at the third HP cultivation. These microorganisms are likely piezophiles and play an important role in degradation of sedimentary organic matter and production of microbial metabolites sustaining the deep microbial ecosystem in the Shimokita Coalbed. The complete 16S sequencing and isolation of piezophiles are now ongoing.

The interplanetary exchange of photosynthesis.

PubMed

Cockell, Charles S

2008-02-01

Panspermia, the transfer of organisms from one planet to another, either through interplanetary or interstellar space, remains speculation. However, its potential can be experimentally tested. Conceptually, it is island biogeography on an interplanetary or interstellar scale. Of special interest is the possibility of the transfer of oxygenic photosynthesis between one planet and another, as it can initiate large scale biospheric productivity. Photosynthetic organisms, which must live near the surface of rocks, can be shown experimentally to be subject to destruction during atmospheric transit. Many of them grow as vegetative cells, which are shown experimentally to be susceptible to destruction by shock during impact ejection, although the effectiveness of this dispersal filter can be shown to be mitigated by the characteristics of the cells and their local environment. Collectively these, and other, experiments reveal the particular barriers to the cross-inoculation of photosynthesis. If oxygen biosignatures are eventually found in the atmospheres of extrasolar planets, understanding the potential for the interplanetary exchange of photosynthesis will aid in their interpretation.

Earth's early biosphere

NASA Technical Reports Server (NTRS)

Des Marais, D. J.

1998-01-01

Understanding our own early biosphere is essential to our search for life elsewhere, because life arose on Earth very early and rocky planets shared similar early histories. The biosphere arose before 3.8 Ga ago, was exclusively unicellular and was dominated by hyperthermophiles that utilized chemical sources of energy and employed a range of metabolic pathways for CO2 assimilation. Photosynthesis also arose very early. Oxygenic photosynthesis arose later but still prior to 2.7 Ga. The transition toward the modern global environment was paced by a decline in volcanic and hydrothermal activity. These developments allowed atmospheric O2 levels to increase. The O2 increase created new niches for aerobic life, most notably the more advanced Eukarya that eventually spawned the megascopic fauna and flora of our modern biosphere.

A test of the 'one-point method' for estimating maximum carboxylation capacity from field-measured, light-saturated photosynthesis

DOE PAGES

Martin G. De Kauwe; Serbin, Shawn P.; Lin, Yan -Shih; ...

2015-12-31

Here, simulations of photosynthesis by terrestrial biosphere models typically need a specification of the maximum carboxylation rate (V cmax). Estimating this parameter using A–C i curves (net photosynthesis, A, vs intercellular CO 2 concentration, C i) is laborious, which limits availability of V cmax data. However, many multispecies field datasets include net photosynthetic rate at saturating irradiance and at ambient atmospheric CO 2 concentration (A sat) measurements, from which V cmax can be extracted using a ‘one-point method’.

Volume-energy parameters for heat transfer to supercritical fluids

NASA Technical Reports Server (NTRS)

Kumakawa, A.; Niino, M.; Hendricks, R. C.; Giarratano, P. J.; Arp, V. D.

1986-01-01

Reduced Nusselt numbers of supercritical fluids from different sources were grouped by several volume-energy parameters. A modified bulk expansion parameter was introduced based on a comparative analysis of data scatter. Heat transfer experiments on liquefied methane were conducted under near-critical conditions in order to confirm the usefulness of the parameters. It was experimentally revealed that heat transfer characteristics of near-critical methane are similar to those of hydrogen. It was shown that the modified bulk expansion parameter and the Gibbs-energy parameter grouped the heat transfer data of hydrogen, oxygen and methane including the present data on near-critical methane. It was also indicated that the effects of surface roughness on heat transfer were very important in grouping the data of high Reynolds numbers.

Minimization of the negative influence on the biosphere in heavy oil extraction and ecologically clean technology for the injection of the steam with supercritical parameters in oil strata on the basis of new ecologically clean tubing pipes with heat-resistant coatings

NASA Astrophysics Data System (ADS)

Komkov, M. A.; Moiseev, V. A.; Tarasov, V. A.; Timofeev, M. P.

2015-12-01

Some ecological problems related to heavy-oil extraction and ways for minimizing the negative impacts of this process on the biosphere are discussed. The ecological hazard of, for example, frequently used multistage hydraulic fracturing of formation is noted and the advantages and perspectives of superheated steam injection are considered. Steam generators of a new type and ecologically clean and costeffective insulating for tubing pipes (TPs) are necessary to develop the superheated steam injection method. The article is devoted to solving one of the most important and urgent tasks, i.e., the development and usage of lightweight, nonflammable, environmentally safe, and cost-effective insulating materials. It is shown that, for tubing shielding operating at temperatures up to 420°C, the most effective thermal insulation is a highly porous material based on basalt fiber. The process of filtration deposition of short basalt fibers with a bunch of alumina thermal insulation tubing pipe coatings in the form of cylinders and cylindrical shells from liquid pulp is substantiated. Based on the thermophysical characteristics of basalt fibers and on the technological features of manufacturing highly porous coating insulation, the thickness of a tubing pipe is determined. During the prolonged pumping of the air at an operating temperature of 400°C in the model sample of tubing pipes with insulation and a protective layer, we find that the surface temperature of the thermal barrier coating does not exceed 60°C. Introducing the described technology will considerably reduce the negative impact of heavy-oil extraction on the biosphere.

Network Analysis of Earth's Co-Evolving Geosphere and Biosphere

NASA Astrophysics Data System (ADS)

Hazen, R. M.; Eleish, A.; Liu, C.; Morrison, S. M.; Meyer, M.; Consortium, K. D.

2017-12-01

A fundamental goal of Earth science is the deep understanding of Earth's dynamic, co-evolving geosphere and biosphere through deep time. Network analysis of geo- and bio- `big data' provides an interactive, quantitative, and predictive visualization framework to explore complex and otherwise hidden high-dimension features of diversity, distribution, and change in the evolution of Earth's geochemistry, mineralogy, paleobiology, and biochemistry [1]. Networks also facilitate quantitative comparison of different geological time periods, tectonic settings, and geographical regions, as well as different planets and moons, through network metrics, including density, centralization, diameter, and transitivity.We render networks by employing data related to geographical, paragenetic, environmental, or structural relationships among minerals, fossils, proteins, and microbial taxa. An important recent finding is that the topography of many networks reflects parameters not explicitly incorporated in constructing the network. For example, networks for minerals, fossils, and protein structures reveal embedded qualitative time axes, with additional network geometries possibly related to extinction and/or other punctuation events (see Figure). Other axes related to chemical activities and volatile fugacities, as well as pressure and/or depth of formation, may also emerge from network analysis. These patterns provide new insights into the way planets evolve, especially Earth's co-evolving geosphere and biosphere. 1. Morrison, S.M. et al. (2017) Network analysis of mineralogical systems. American Mineralogist 102, in press. Figure Caption: A network of Phanerozoic Era fossil animals from the past 540 million years includes blue, red, and black circles (nodes) representing family-level taxa and grey lines (links) between coexisting families. Age information was not used in the construction of this network; nevertheless an intrinsic timeline is embedded in the network topology. In addition, two mass extinction events appear as "pinch points" in the network.

Detection and Attribution of Simulated Climatic Extreme Events and Impacts: High Sensitivity to Bias Correction

NASA Astrophysics Data System (ADS)

Sippel, S.; Otto, F. E. L.; Forkel, M.; Allen, M. R.; Guillod, B. P.; Heimann, M.; Reichstein, M.; Seneviratne, S. I.; Kirsten, T.; Mahecha, M. D.

2015-12-01

Understanding, quantifying and attributing the impacts of climatic extreme events and variability is crucial for societal adaptation in a changing climate. However, climate model simulations generated for this purpose typically exhibit pronounced biases in their output that hinders any straightforward assessment of impacts. To overcome this issue, various bias correction strategies are routinely used to alleviate climate model deficiencies most of which have been criticized for physical inconsistency and the non-preservation of the multivariate correlation structure. We assess how biases and their correction affect the quantification and attribution of simulated extremes and variability in i) climatological variables and ii) impacts on ecosystem functioning as simulated by a terrestrial biosphere model. Our study demonstrates that assessments of simulated climatic extreme events and impacts in the terrestrial biosphere are highly sensitive to bias correction schemes with major implications for the detection and attribution of these events. We introduce a novel ensemble-based resampling scheme based on a large regional climate model ensemble generated by the distributed weather@home setup[1], which fully preserves the physical consistency and multivariate correlation structure of the model output. We use extreme value statistics to show that this procedure considerably improves the representation of climatic extremes and variability. Subsequently, biosphere-atmosphere carbon fluxes are simulated using a terrestrial ecosystem model (LPJ-GSI) to further demonstrate the sensitivity of ecosystem impacts to the methodology of bias correcting climate model output. We find that uncertainties arising from bias correction schemes are comparable in magnitude to model structural and parameter uncertainties. The present study consists of a first attempt to alleviate climate model biases in a physically consistent way and demonstrates that this yields improved simulations of climate extremes and associated impacts. [1] http://www.climateprediction.net/weatherathome/

The UNESCO biosphere reserve concept as a tool for urban sustainability: the CUBES Cape Town case study.

PubMed

Stanvliet, R; Jackson, J; Davis, G; De Swardt, C; Mokhoele, J; Thom, Q; Lane, B D

2004-06-01

The Cape Town Case Study (CTCS) was a multi-institutional collaborative project initiated by CUBES, a knowledge networking initiative of UNESCO's Ecological Sciences Division and the Earth Institute at Columbia University. Cape Town was selected as a CUBES site on the basis of its high biological and cultural significance, together with its demonstrated leadership in promoting urban sustainability. The CTCS was conducted by the Cape Town Urban Biosphere Group, a cross-disciplinary group of specialists drawn from national, provincial, municipal, and civil society institutions, mandated to examine the potential value of the UNESCO Biosphere Reserve concept as a tool for environmental management, social inclusion, and poverty alleviation in Cape Town. This article provides a contextualization of the CTCS and its collaborative process. It also reviews the biosphere reserve concept relative to urban sustainability objectives and proposes a more functional application of that concept in an urban context. A detailed analysis of key initiatives at the interface of conservation and poverty alleviation is provided in table format. Drawing on an examination of successful sustainability initiatives in Cape Town, specific recommendations are made for future application of the biosphere reserve concept in an urban context, as well as a model by which urban areas might affiliate with the UNESCO World Network of Biosphere Reserves, and criteria for such affiliation.

Lignocellulose deconstruction in the biosphere

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bomble, Yannick J.; Lin, Chien-Yuan; Amore, Antonella

Microorganisms have evolved different and yet complementary mechanisms to degrade biomass in the biosphere. The chemical biology of lignocellulose deconstruction is a complex and intricate process that appears to vary in response to specific ecosystems. These microorganisms rely on simple to complex arrangements of glycoside hydrolases to conduct most of these polysaccharide depolymerization reactions and also, as discovered more recently, oxidative mechanisms via lytic polysaccharide monooxygenases or non-enzymatic Fenton reactions which are used to enhance deconstruction. It is now clear that these deconstruction mechanisms are often more efficient in the presence of the microorganisms. In general, a major fraction ofmore » the total plant biomass deconstruction in the biosphere results from the action of various microorganisms, primarily aerobic bacteria and fungi, as well as a variety of anaerobic bacteria. Beyond carbon recycling, specialized microorganisms interact with plants to manage nitrogen in the biosphere. Understanding the interplay between these organisms within or across ecosystems is crucial to further our grasp of chemical recycling in the biosphere and also enables optimization of the burgeoning plant-based bioeconomy.« less

Top–down assessment of the Asian carbon budget since the mid 1990s

PubMed Central

Thompson, R. L.; Patra, P. K.; Chevallier, F.; Maksyutov, S.; Law, R. M.; Ziehn, T.; van der Laan-Luijkx, I. T.; Peters, W.; Ganshin, A.; Zhuravlev, R.; Maki, T.; Nakamura, T.; Shirai, T.; Ishizawa, M.; Saeki, T.; Machida, T.; Poulter, B.; Canadell, J. G.; Ciais, P.

2016-01-01

Increasing atmospheric carbon dioxide (CO2) is the principal driver of anthropogenic climate change. Asia is an important region for the global carbon budget, with 4 of the world's 10 largest national emitters of CO2. Using an ensemble of seven atmospheric inverse systems, we estimated land biosphere fluxes (natural, land-use change and fires) based on atmospheric observations of CO2 concentration. The Asian land biosphere was a net sink of −0.46 (−0.70–0.24) PgC per year (median and range) for 1996–2012 and was mostly located in East Asia, while in South and Southeast Asia the land biosphere was close to carbon neutral. In East Asia, the annual CO2 sink increased between 1996–2001 and 2008–2012 by 0.56 (0.30–0.81) PgC, accounting for ∼35% of the increase in the global land biosphere sink. Uncertainty in the fossil fuel emissions contributes significantly (32%) to the uncertainty in land biosphere sink change. PMID:26911442

Lignocellulose deconstruction in the biosphere.

PubMed

Bomble, Yannick J; Lin, Chien-Yuan; Amore, Antonella; Wei, Hui; Holwerda, Evert K; Ciesielski, Peter N; Donohoe, Bryon S; Decker, Stephen R; Lynd, Lee R; Himmel, Michael E

2017-12-01

Microorganisms have evolved different and yet complementary mechanisms to degrade biomass in the biosphere. The chemical biology of lignocellulose deconstruction is a complex and intricate process that appears to vary in response to specific ecosystems. These microorganisms rely on simple to complex arrangements of glycoside hydrolases to conduct most of these polysaccharide depolymerization reactions and also, as discovered more recently, oxidative mechanisms via lytic polysaccharide monooxygenases or non-enzymatic Fenton reactions which are used to enhance deconstruction. It is now clear that these deconstruction mechanisms are often more efficient in the presence of the microorganisms. In general, a major fraction of the total plant biomass deconstruction in the biosphere results from the action of various microorganisms, primarily aerobic bacteria and fungi, as well as a variety of anaerobic bacteria. Beyond carbon recycling, specialized microorganisms interact with plants to manage nitrogen in the biosphere. Understanding the interplay between these organisms within or across ecosystems is crucial to further our grasp of chemical recycling in the biosphere and also enables optimization of the burgeoning plant-based bioeconomy. Copyright © 2017. Published by Elsevier Ltd.

Analysis of Low-Biomass Microbial Communities in the Deep Biosphere.

PubMed

Morono, Y; Inagaki, F

2016-01-01

Over the past few decades, the subseafloor biosphere has been explored by scientific ocean drilling to depths of about 2.5km below the seafloor. Although organic-rich anaerobic sedimentary habitats in the ocean margins harbor large numbers of microbial cells, microbial populations in ultraoligotrophic aerobic sedimentary habitats in the open ocean gyres are several orders of magnitude less abundant. Despite advances in cultivation-independent molecular ecological techniques, exploring the low-biomass environment remains technologically challenging, especially in the deep subseafloor biosphere. Reviewing the historical background of deep-biosphere analytical methods, the importance of obtaining clean samples and tracing contamination, as well as methods for detecting microbial life, technological aspects of molecular microbiology, and detecting subseafloor metabolic activity will be discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparison of Regression Analysis and Transfer Function in Estimating the Parameters of Central Pulse Waves from Brachial Pulse Wave.

PubMed

Chai, Rui; Xu, Li-Sheng; Yao, Yang; Hao, Li-Ling; Qi, Lin

2017-01-01

This study analyzed ascending branch slope (A_slope), dicrotic notch height (Hn), diastolic area (Ad) and systolic area (As) diastolic blood pressure (DBP), systolic blood pressure (SBP), pulse pressure (PP), subendocardial viability ratio (SEVR), waveform parameter (k), stroke volume (SV), cardiac output (CO), and peripheral resistance (RS) of central pulse wave invasively and non-invasively measured. Invasively measured parameters were compared with parameters measured from brachial pulse waves by regression model and transfer function model. Accuracy of parameters estimated by regression and transfer function model, was compared too. Findings showed that k value, central pulse wave and brachial pulse wave parameters invasively measured, correlated positively. Regression model parameters including A_slope, DBP, SEVR, and transfer function model parameters had good consistency with parameters invasively measured. They had same effect of consistency. SBP, PP, SV, and CO could be calculated through the regression model, but their accuracies were worse than that of transfer function model.

Biosphere2 and Earthbuzz

NASA Astrophysics Data System (ADS)

Washburne, J. C.

2009-12-01

In an attempt to reach a broader audience, Biosphere 2, near Tucson, AZ, is participating in a network of science centers thanks to new funding through the Science Museum of Minnesota (SMM) and the National Center for Earth System Dynamics (NCED). Each of these centers will be tied together through an Earthbuzz kiosk, basically a networked web site that allows visitors to learn more about the work of leading local scientists in a very personal and captivating format. Content is currently being developed by Biosphere 2 researchers, staff, and graduate students that range from a public question and answer forum called “Scientist on the Spot” to science blogs by Biosphere 2 Fellows. It is hoped that this project will help educate the public about the Anthropocene, that is, the current geologic period that is so greatly affected by humankind’s impact on the health of the planet. Biosphere 2 provides a unique location to engage the public in this conversation for several reasons. First, no other destination on Earth gives the public such a physical immersion into what climate change might mean as does Biosphere 2. On the regular walking tour, visitors are guided through scaled down versions of an African savannah, a semi-arid thorn scrub, a coastal fog desert and a tropical rainforest. Digital displays of temperature and humidity confirm what your body is feeling - conditions ranging from desert aridity to tropical humidity. As one passes through the biomes of Biosphere 2, climate change is a whole body experience. Second, Biosphere 2 is also an active ecological research site - part of a unique network of sites run by the University of Arizona that allow scientists to study ecosystem processes across a range of scales - from microscopic root studies to studies encompassing large watersheds. In particular, a group of researchers is studying why large stands of pinion-juniper forests across the southwest have died in recent years. Biosphere2’s role in this experiment is multi-faceted. Boxed Pinion pines have been placed in a setting that allows close regulation of both temperature and precipitation while being intensively monitored electronically. Graduate students are learning field protocols in close proximity to their classes and are encouraged to interact with the almost hourly public tours. While many scientists are able to wow their peers at AGU, it is quite another thing to assess the ever changing mix of ages and interests present in the tour groups and to clearly communicate your scientific objectives and to explain what you happen to be working on today. These and many other examples will be highlighted in this presentation of how Biosphere 2 is developing an Earthbuzz kiosk in conjunction with the SMM and NCED.

Prebiological Synthesis Organic Matter and Origin of Life in Protoplanetary Disks

NASA Astrophysics Data System (ADS)

Snytnikov, V. N.

2017-05-01

Processes and conditions around new born Sun and possibly other young stars led to the origin of life in the circumstellar disc in a few million years. Than the circumsolar biosphere evolved to its current earth state. In agreement with the main results of the natural sciences and the theory of self-organization, several stages are necessary for the life to emerge on the Earth. Nowday we can specify "The cold prehistiry of the life", "RNA-world", "Preplanet biosphere", "Destructive biosphere", "Earth of bacteria".

Production of EPA and DHA in aquatic ecosystems and their transfer to the land.

PubMed

Gladyshev, Michail I; Sushchik, Nadezhda N; Makhutova, Olesia N

2013-12-01

Most omnivorous animals, including humans, have to some degree relied on physiologically important polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from food. Only some taxa of microalgae, rather than higher plants can synthesize de novo high amounts of EPA and DHA. Once synthesized by microalgae, PUFA are transferred through trophic chain to organisms of higher levels. Thus, aquatic ecosystems play the unique role in the Biosphere as the principal source of EPA and DHA for most omnivorous animals, including inhabitants of terrestrial ecosystems. PUFA are transferred from aquatic to terrestrial ecosystems through riparian predators, drift of carrion and seaweeds, emergence of amphibiotic insects, and water birds. The essential PUFA are transferred through trophic chains with about twice higher efficiency than bulk carbon. Thereby, PUFA are accumulated, rather than diluted in biomass of organisms of higher trophic levels, e.g., in fish. Mankind is faced with a severe deficiency of EPA and DHA in diet. Although additional sources of PUFA supply for humans, such as aquaculture, biotechnology of microorganisms and transgenic terrestrial oil-seed producing plants are developed, natural fish production of aquatic ecosystems will remain one of the main sources of EPA and DHA for humans. Aquatic ecosystems have to be protected from anthropogenic impacts, such as eutrophication, pollution and warming, which reduce PUFA production. Copyright © 2013 Elsevier Inc. All rights reserved.

The water cycle in closed ecological systems: perspectives from the Biosphere 2 and Laboratory Biosphere systems

NASA Astrophysics Data System (ADS)

Nelson, Mark; Dempster, William; Allen, John P.

To achieve sustainable and healthy closed ecological systems requires successful solutions to the challenge of closing the water cycle - recycling wastewater/soil leachate and evaporateed water and supplying water of required quality as needed for different needs within the facility. Engineering Biosphere 2, the first multi-biome closed ecological system, total footprint of the airtight area is 12,700 m2 with a combined volume of 200,000 m3 with a total water capacity of some 6 x 106 liters of water presented a complex challenge because it included human inhabitants, their agricultural and technical systems, as well as a range of analogue ecosystems ranging from rainforest to desert, freshwater ecologies to mini-ocean coral reef ecosystems. By contrast, the Laboratory Biosphere - a small (40m3 volume) soil-based plant growth facility with a footprint of 15m3 - is a very simplified system, but with some similar issues such as salinity management and the provision of water quality sufficient for plant growth. In Biosphere 2, water needs included supplying potable water for people and domestic animals, irrigation water for a wide variety of food crops, and recycling and recovering soil nutrients from wastewater. In the wilderness biomes, adequately freshwater was needed for terrestrial ecosystems and maintaining appropriate salinity and pH in aquatic/marine ecosystems. The largest reservoirs in Biosphere 2 were the ocean/marsh with some 4x106 liters, soil with 2 x 106 liters, primary storage tanks with a capacity for up to 8 x 105 liters and storage tanks for condensate collection and mixing tanks with 1.5 x 105 liters to supply irrigation for farm and wilderness ecosystems. Other reservoirs were far smaller - humidity in the atmosphere (2 x 103 liters), streams in the rainforest and savannah, and seasonal pools in the desert were orders of magnitude smaller (8 x 103 liters). Key technologies included condensation from humidity in the airhandlers and from the glass spaceframe to produce high quality freshwater, purification of nutrients from ocean waters with first algae mats and then protein skimmers, wastewater treatment with constructed wetlands and desalination through reverse osmosis and flash evaporation were key to recycling water with appropriate quality throughout the Biosphere 2 facility. Wastewater from all human uses and the domestic animals in Biosphere 2 was treated and recycling through a series of constructed wetlands, which had hydraulic loading of 0.9-1.1 m3 day-1 (240-290 gal d-1). Plant production in the wetland treatment system produced 1210 kg dry weight of emergent and floating aquatic plant wetland used as fodder for the domestic animals and remaining nutrients/water was reused as part of the agricultural irrigation supply. There were pools of water with recycling times of days to weeks and others with far longer cycling times within Biosphere 2. By contrast, the Laboratory Biosphere with a total water reservoir of less than 500 litres has far quicker cycling rapidity. However, just as in Biosphere 2, humidity in the Laboratory Biosphere is a very small reservoir of water. The amount of water passing through the air in the course of a 12-hour operational day is two orders of magnitude greater than the amount stored in the air. Thus evaporation, condensation and soil leachate collection are vital parts of the recycle system just as in Biosphere 2. The water cycle and sustainable water recycling in closed ecological systems presents problems requiring further research to resolve - such as how to control buildup of salinity in materially-closed ecosystems and effective ways to retain nutrients in optimal quantity and useable form for plant growth which are common to closed ecological systems of whatever size. These issues have relevance to a global environment increasingly facing water shortages and the task of maintaining water quality for human and ecosystem health.

Variability of Phenology and Fluxes of Water and Carbon with Observed and Simulated Soil Moisture in the Ent Terrestrial Biosphere Model (Ent TBM Version 1.0.1.0.0)

NASA Technical Reports Server (NTRS)

Kim, Y.; Moorcroft, P. R.; Aleinov, Igor; Puma, M. J.; Kiang, N. Y.

2015-01-01

The Ent Terrestrial Biosphere Model (Ent TBM) is a mixed-canopy dynamic global vegetation model developed specifically for coupling with land surface hydrology and general circulation models (GCMs). This study describes the leaf phenology submodel implemented in the Ent TBM version 1.0.1.0.0 coupled to the carbon allocation scheme of the Ecosystem Demography (ED) model. The phenology submodel adopts a combination of responses to temperature (growing degree days and frost hardening), soil moisture (linearity of stress with relative saturation) and radiation (light length). Growth of leaves, sapwood, fine roots, stem wood and coarse roots is updated on a daily basis. We evaluate the performance in reproducing observed leaf seasonal growth as well as water and carbon fluxes for four plant functional types at five Fluxnet sites, with both observed and prognostic hydrology, and observed and prognostic seasonal leaf area index. The phenology submodel is able to capture the timing and magnitude of leaf-out and senescence for temperate broadleaf deciduous forest (Harvard Forest and Morgan- Monroe State Forest, US), C3 annual grassland (Vaira Ranch, US) and California oak savanna (Tonzi Ranch, US). For evergreen needleleaf forest (Hyytiäla, Finland), the phenology submodel captures the effect of frost hardening of photosynthetic capacity on seasonal fluxes and leaf area. We address the importance of customizing parameter sets of vegetation soil moisture stress response to the particular land surface hydrology scheme. We identify model deficiencies that reveal important dynamics and parameter needs.

Variability of phenology and fluxes of water and carbon with observed and simulated soil moisture in the Ent Terrestrial Biosphere Model (Ent TBM version 1.0.1.0.0)

NASA Astrophysics Data System (ADS)

Kim, Y.; Moorcroft, P. R.; Aleinov, I.; Puma, M. J.; Kiang, N. Y.

2015-12-01

The Ent Terrestrial Biosphere Model (Ent TBM) is a mixed-canopy dynamic global vegetation model developed specifically for coupling with land surface hydrology and general circulation models (GCMs). This study describes the leaf phenology submodel implemented in the Ent TBM version 1.0.1.0.0 coupled to the carbon allocation scheme of the Ecosystem Demography (ED) model. The phenology submodel adopts a combination of responses to temperature (growing degree days and frost hardening), soil moisture (linearity of stress with relative saturation) and radiation (light length). Growth of leaves, sapwood, fine roots, stem wood and coarse roots is updated on a daily basis. We evaluate the performance in reproducing observed leaf seasonal growth as well as water and carbon fluxes for four plant functional types at five Fluxnet sites, with both observed and prognostic hydrology, and observed and prognostic seasonal leaf area index. The phenology submodel is able to capture the timing and magnitude of leaf-out and senescence for temperate broadleaf deciduous forest (Harvard Forest and Morgan-Monroe State Forest, US), C3 annual grassland (Vaira Ranch, US) and California oak savanna (Tonzi Ranch, US). For evergreen needleleaf forest (Hyytiäla, Finland), the phenology submodel captures the effect of frost hardening of photosynthetic capacity on seasonal fluxes and leaf area. We address the importance of customizing parameter sets of vegetation soil moisture stress response to the particular land surface hydrology scheme. We identify model deficiencies that reveal important dynamics and parameter needs.

Cycles Tipping the Scale between Death and Survival (=``Life")

NASA Astrophysics Data System (ADS)

Halberg, F.; Cornélissen, G.; Sothern, R. B.; Katinas, G. S.; Schwartzkopff, O.; Otsuka, K.

Systematic chronobiologically interpreted ambulatory bloodpressure (BP) and heart rate (HR) monitoring (C-ABPM 7D/24H is now automatically possible; if continued around the clock over a week, this approach detects vascular variability disorders (VVDs) that include, among others, high BP itself and CHAT, short for circadian hyper-amplitude-tension. BP is never a constant ``true" (resting) value and can be more reliably diagnosed by CABPM 7d/24h as MESOR-hypertension, MH. CHAT carries a risk of hard events greater than MH and can be treated, among other VVDs, which if they coexist constitute vascular variability syndromes (VVSs). A project on The BIOsphere and the COSmos, BIOCOS (corne001@umn.edu), provides, in exchange for the data, cost-free analyses and the opportunity of obtaining monitors at a cost reduction of 80% complements the records from purely physical tools for surveilling the variable sun, by validating in the biosphere the reality of intermittent, aeolian envi ronmental spectral components that can be more consistent than their physical counterparts once they are coded in genes. C-ABPM 7D/24H indicates relevant associations of space weather with human health and ecology. Monitoring reveals, around and in living matter, a system of transdisciplinary cycles with common average periods, quantified with point-and-interval estimates of parameters. The cycles in space climate are critical in discussing global warming. The cycles' periods are described as congruent when their CIs (95\\ intervals) overlie or overlap and the amplitudes' CIs' lower limits are positive. Some congruent cycles in organisms, counterparts of the environmental day and the seasons, relate to electromagnetic radiation in the visible domain; these are the usually environmentally synchronized socio-photo-thermoperiodisms (photics). The biosphere also resonates with or is pulled or driven by nonstationary, environmental nonphotic cycles (nonphotics) -- particle emissi ons from the sun and the wider cosmos, cosmoheliogeomagnetics, ultraviolet flux, gravitation, acoustics and others. Nonphotics, a set of in part transdisciplinarily-novel spectral components, can be intermittent; when present, they coexist and compete with signatures of photic cycles, monitored, e.g., in BP and HR. Nonphotics of, e.g., about (˜) 1 week (circaseptans) and ˜17 months (transyears), characterize mood and performance, modulate and sometimes override society's (photic) schedules, even in dying suddenly either unintentionally or by one's own will or at the hand of others. Nonphotics persist, but are damped in physiology or in terrorism, when their environmental counterpart is not detected. Their elucidation provides information on how a set of cycles covering 18 orders of magnitude in the frequency domain of the biosphere bears on the question ``What is life?": a resonance of the biosphere with periods of its environment constitutes life itself.

In situ Detection of Microbial Life in the Deep Biosphere in Igneous Ocean Crust.

PubMed

Salas, Everett C; Bhartia, Rohit; Anderson, Louise; Hug, William F; Reid, Ray D; Iturrino, Gerardo; Edwards, Katrina J

2015-01-01

The deep biosphere is a major frontier to science. Recent studies have shown the presence and activity of cells in deep marine sediments and in the continental deep biosphere. Volcanic lavas in the deep ocean subsurface, through which substantial fluid flow occurs, present another potentially massive deep biosphere. We present results from the deployment of a novel in situ logging tool designed to detect microbial life harbored in a deep, native, borehole environment within igneous oceanic crust, using deep ultraviolet native fluorescence spectroscopy. Results demonstrate the predominance of microbial-like signatures within the borehole environment, with densities in the range of 10(5) cells/mL. Based on transport and flux models, we estimate that such a concentration of microbial cells could not be supported by transport through the crust, suggesting in situ growth of these communities.

Understanding local community's values, worldviews and perceptions in the Galloway and Southern Ayrshire Biosphere Reserve, Scotland.

PubMed

Hernes, Maya I; Metzger, Marc J

2017-01-15

Biosphere reserves have been studied around the world, but methods to elicit community's values, worldviews and perceptions are missing. A greater understanding of these can help avoid tension and improve successful management. This paper used a mixed-methods survey to elicit local community's environmental values, ecological world views and perceptions of the Galloway and Southern Ayrshire Biosphere Reserve (GSABR). Over three weeks, forty participants from three communities of the GSABR responded to a semi-structured mixed-methods survey. The survey revealed that residents of the GSABR greatly value wildlife and beauty of nature, and that the majority of the respondents showed concern for the environment from an ecocentric worldview. Results also revealed that the most influential tested socio-demographic characteristic affecting people's relationship to their environment is their professional affiliation. Tourism and recreation were seen as major benefits of the recent biosphere designation. Results did highlight contrasting benefits from the designation for different stakeholder groups, which could potentially lead to tensions and should be considered in the reserve management. Given the community's supportive world views and perceptions, greater participation in the biosphere's management in likely to be welcomed and should be used to avoid or mediate any conflicts. The mixed-method survey developed for this study, proved successful in eliciting these themes in the GSABR. We recommend other biosphere reserves replicate this research, to gain better understanding of local communities and increase their support and participation in reserve management. Copyright © 2016 Elsevier Ltd. All rights reserved.

Calibration of two complex ecosystem models with different likelihood functions

NASA Astrophysics Data System (ADS)

Hidy, Dóra; Haszpra, László; Pintér, Krisztina; Nagy, Zoltán; Barcza, Zoltán

2014-05-01

The biosphere is a sensitive carbon reservoir. Terrestrial ecosystems were approximately carbon neutral during the past centuries, but they became net carbon sinks due to climate change induced environmental change and associated CO2 fertilization effect of the atmosphere. Model studies and measurements indicate that the biospheric carbon sink can saturate in the future due to ongoing climate change which can act as a positive feedback. Robustness of carbon cycle models is a key issue when trying to choose the appropriate model for decision support. The input parameters of the process-based models are decisive regarding the model output. At the same time there are several input parameters for which accurate values are hard to obtain directly from experiments or no local measurements are available. Due to the uncertainty associated with the unknown model parameters significant bias can be experienced if the model is used to simulate the carbon and nitrogen cycle components of different ecosystems. In order to improve model performance the unknown model parameters has to be estimated. We developed a multi-objective, two-step calibration method based on Bayesian approach in order to estimate the unknown parameters of PaSim and Biome-BGC models. Biome-BGC and PaSim are a widely used biogeochemical models that simulate the storage and flux of water, carbon, and nitrogen between the ecosystem and the atmosphere, and within the components of the terrestrial ecosystems (in this research the developed version of Biome-BGC is used which is referred as BBGC MuSo). Both models were calibrated regardless the simulated processes and type of model parameters. The calibration procedure is based on the comparison of measured data with simulated results via calculating a likelihood function (degree of goodness-of-fit between simulated and measured data). In our research different likelihood function formulations were used in order to examine the effect of the different model goodness metric on calibration. The different likelihoods are different functions of RMSE (root mean squared error) weighted by measurement uncertainty: exponential / linear / quadratic / linear normalized by correlation. As a first calibration step sensitivity analysis was performed in order to select the influential parameters which have strong effect on the output data. In the second calibration step only the sensitive parameters were calibrated (optimal values and confidence intervals were calculated). In case of PaSim more parameters were found responsible for the 95% of the output data variance than is case of BBGC MuSo. Analysis of the results of the optimized models revealed that the exponential likelihood estimation proved to be the most robust (best model simulation with optimized parameter, highest confidence interval increase). The cross-validation of the model simulations can help in constraining the highly uncertain greenhouse gas budget of grasslands.

The Jena Diversity Model: Towards a Richer Representation of the Terrestrial Biosphere for Earth System Modelling

NASA Astrophysics Data System (ADS)

Pavlick, R.; Reu, B.; Bohn, K.; Dyke, J.; Kleidon, A.

2010-12-01

The terrestrial biosphere is a complex, self-organizing system which is continually both adapting to and altering its global environment. It also exhibits a vast diversity of vegetation forms and functioning. However, the terrestrial biosphere components within current state-of-the-art Earth System Models abstract this diversity in to a handful of relatively static plant functional types. These coarse and static representations of functional diversity might contribute to overly pessimistic projections regarding terrestrial ecosystem responses to scenarios of global change (e.g. Amazonian and boreal forest diebacks). In the Jena Diversity (JeDi) model, we introduce a new approach to vegetation modelling with a richer representation of functional diversity, based not on plant functional types, but on unavoidable plant ecophysiological trade-offs, which we hypothesize should be more stable in time. The JeDi model tests a large number of plant growth strategies. Each growth strategy is simulated using a set of randomly generated parameter values, which characterize its functioning in terms of carbon allocation, ecophysiology, and phenology, which are then linked to the growing conditions at the land surface. The model is constructed in such a way that these parameters inherently lead to ecophysiological trade-offs, which determine whether a growth strategy is able to survive and reproduce under the prevalent climatic conditions. Kleidon and Mooney (2000) demonstrated that this approach is capable of reproducing the geographic distribution of species richness. More recently, we have shown the JeDi model can explain other biogeographical phenomena including the present-day global pattern of biomes (Reu et al., accepted), ecosystem evenness (Kleidon et al. 2009), and possible mechanisms for biome shifts and biodiversity changes under scenarios of global warming (Reu et al., submitted). We have also evaluated the simulated biogeochemical fluxes from JeDi against a variety of site, field, and satellite observations (Pavlick et al., submitted) following a protocol established by the Carbon-Land Model Intercomparison Project (Randerson et al. 2009). We found that the global patterns of biogeochemical fluxes and land surface properties are reasonably well simulated using this bottom-up trade-off approach and compare favorably with other state of the art terrestrial biosphere models. Here, we present some results from JeDi simulations, wherein we varied the modelled functional diversity to quantify its impact on terrestrial biogeochemical fluxes under both present-day conditions and projected scenarios of global change. We also present results from a set of simulations wherein we vary the ability of the modelled ecosystems to adapt through changes in functional composition, leading to different projection responses of the carbon cycle to global warming. This plant functional tradeoff approach sets the foundation for many applications, including exploring the emergence and climatic impacts of major vegetation transitions throughout the last 400 million years as well as quantifying the significance of preserving functional diversity to hedge against uncertain climates in the future.

Geospatial assessment and monitoring of historical forest cover changes (1920-2012) in Nilgiri Biosphere Reserve, Western Ghats, India.

PubMed

Satish, K V; Saranya, K R L; Reddy, C Sudhakar; Krishna, P Hari; Jha, C S; Rao, P V V Prasada

2014-12-01

Deforestation in the biosphere reserves, which are key Protected Areas has negative impacts on biodiversity, climate, carbon fluxes and livelihoods. Comprehensive study of deforestation in biosphere reserves is required to assess the impact of the management effectiveness. This article assesses the changes in forest cover in various zones and protected areas of Nilgiri Biosphere Reserve, the first declared biosphere reserve in India which forms part of Western Ghats-a global biodiversity hotspot. In this study, we have mapped the forests from earliest available topographical maps and multi-temporal satellite data spanning from 1920's to 2012 period. Mapping of spatial extent of forest cover, vegetation types and land cover was carried out using visual interpretation technique. A grid cell of 1 km × 1 km was generated for time series change analysis to understand the patterns in spatial distribution of forest cover (1920-1973-1989-1999-2006-2012). The total forest area of biosphere reserve was found to be 5,806.5 km(2) (93.8 % of total geographical area) in 1920. Overall loss of forest cover was estimated as 1,423.6 km(2) (24.5 % of the total forest) with reference to 1920. Among the six Protected Areas, annual deforestation rate of >0.5 was found in Wayanad wildlife sanctuary during 1920-1973. The deforestation in Nilgiri Biosphere Reserve is mainly attributed to conversion of forests to plantations and agriculture along with submergence due to construction of dams during 1920 to 1989. Grid wise analysis indicates that 851 grids have undergone large-scale negative changes of >75 ha of forest loss during 1920-1973 while, only 15 grids have shown >75 ha loss during 1973-1989. Annual net rate of deforestation for the period of 1920 to 1973 was calculated as 0.5 followed by 0.1 for 1973 to 1989. Our analysis shows that there was large-scale deforestation before the declaration of area as biosphere reserve in 1986; however, the deforestation has drastically reduced after the declaration due to high degree of protection, thus indicating the secure future of reserve in the long term under the current forest management practices. The present work will stand as the most up-to-date assessment on the forest cover of the Nilgiri Biosphere Reserve with immediate applications in monitoring and management of forest biodiversity.

A biosphere modeling methodology for dose assessments of the potential Yucca Mountain deep geological high level radioactive waste repository.

PubMed

Watkins, B M; Smith, G M; Little, R H; Kessler, J

1999-04-01

Recent developments in performance standards for proposed high level radioactive waste disposal at Yucca Mountain suggest that health risk or dose rate limits will likely be part of future standards. Approaches to the development of biosphere modeling and dose assessments for Yucca Mountain have been relatively lacking in previous performance assessments due to the absence of such a requirement. This paper describes a practical methodology used to develop a biosphere model appropriate for calculating doses from use of well water by hypothetical individuals due to discharges of contaminated groundwater into a deep well. The biosphere model methodology, developed in parallel with the BIOMOVS II international study, allows a transparent recording of the decisions at each step, from the specification of the biosphere assessment context through to model development and analysis of results. A list of features, events, and processes relevant to Yucca Mountain was recorded and an interaction matrix developed to help identify relationships between them. Special consideration was given to critical/potential exposure group issues and approaches. The conceptual model of the biosphere system was then developed, based on the interaction matrix, to show how radionuclides migrate and accumulate in the biosphere media and result in potential exposure pathways. A mathematical dose assessment model was specified using the flexible AMBER software application, which allows users to construct their own compartment models. The starting point for the biosphere calculations was a unit flux of each radionuclide from the groundwater in the geosphere into the drinking water in the well. For each of the 26 radionuclides considered, the most significant exposure pathways for hypothetical individuals were identified. For 14 of the radionuclides, the primary exposure pathways were identified as consumption of various crops and animal products following assumed agricultural use of the contaminated water derived from the deep well. Inhalation of dust (11 radionuclides) and external irradiation (1 radionuclide) were also identified as significant exposure modes. Contribution to the total flux to dose conversion factor from the drinking water pathway for each radionuclide was also assessed and for most radionuclides was found to be less than 10% of the total flux to dose conversion factor summed across all pathways. Some of the uncertainties related to the results were considered. The biosphere modeling results have been applied within an EPRI Total Systems Performance Assessment of Yucca Mountain. Conclusions and recommendations for future performance assessments are provided.

Regular patterns of Cs-137 distribution in natural conjugated elementary landscapes as a result of a balanced surface and depth water migration

NASA Astrophysics Data System (ADS)

Korobova, Elena; Romanov, Sergey

2016-04-01

Distribution of artificial radionuclides in the environment has long been used successfully for revealing migration pathways of their stable analogues. Migration of water in natural conjugated elementary landscapes characterizing the system of top-slope-resulting depression, has a specific structure and the radionuclide tracer is inevitably reflecting it by specific sorption and exchange processes. Other important issues are the concentration levels and the difference in characteristic time of chemical element dispersion. Modern biosphere has acquired its sustainable structure within a long period of time and is formed by basic macroelements allowing the water soluble portion of elements functioning as activators of chemical exchange. Water migration is controlled by gravitation, climate and relief while fixation depends upon the parameters of surfaces and chemical composition. The resulting structure depends on specificity and duration of the process. The long-term redistribution of chemical elements in terrestrial environment has led to a distinct geochemical structure of conjugated landscapes with a specific geometry of redistribution and accumulation of chemical elements. Migration of the newly born anthropogenic radionuclides followed natural pathways in biosphere. The initial deposition of the Chernobyl's radionuclides within the elementary landscape-geochemical system was even by condition of aerial deposition. But further exchange process is controlled by the strength of fixation and migration ability of the carriers. Therefore patterns of spatial distribution of artificial radionuclides in natural landscapes are considerably different as compared to those of the long-term forming the basic structure of chemical fields in biosphere. Our monitoring of Cs-137 radial and lateral distribution in the test plots characterizing natural undisturbed conjugated elementary landscapes performed in the period from 2005 until now has revealed a stable and specifically polycentric structure of radiocesium distribution believed to reflect the character of radial and lateral water body migration and a high sensitivity of water distribution to surface parameters. This leads to an unusual wavy type of Cs-137 distribution down, along and across all the slopes examined for surface Cs-137 activity at every measured point. The finding is believed to have an important practical outcome allowing much more detailed evaluation of micronutrients distribution and optimization of their application.

A Thermal Evolution Model of the Earth Including the Biosphere, Continental Growth and Mantle Hydration

NASA Astrophysics Data System (ADS)

Höning, D.; Spohn, T.

2014-12-01

By harvesting solar energy and converting it to chemical energy, photosynthetic life plays an important role in the energy budget of Earth [2]. This leads to alterations of chemical reservoirs eventually affecting the Earth's interior [4]. It further has been speculated [3] that the formation of continents may be a consequence of the evolution life. A steady state model [1] suggests that the Earth without its biosphere would evolve to a steady state with a smaller continent coverage and a dryer mantle than is observed today. We present a model including (i) parameterized thermal evolution, (ii) continental growth and destruction, and (iii) mantle water regassing and outgassing. The biosphere enhances the production rate of sediments which eventually are subducted. These sediments are assumed to (i) carry water to depth bound in stable mineral phases and (ii) have the potential to suppress shallow dewatering of the underlying sediments and crust due to their low permeability. We run a Monte Carlo simulation for various initial conditions and treat all those parameter combinations as success which result in the fraction of continental crust coverage observed for present day Earth. Finally, we simulate the evolution of an abiotic Earth using the same set of parameters but a reduced rate of continental weathering and erosion. Our results suggest that the origin and evolution of life could have stabilized the large continental surface area of the Earth and its wet mantle, leading to the relatively low mantle viscosity we observe at present. Without photosynthetic life on our planet, the Earth would be geodynamical less active due to a dryer mantle, and would have a smaller fraction of continental coverage than observed today. References[1] Höning, D., Hansen-Goos, H., Airo, A., Spohn, T., 2014. Biotic vs. abiotic Earth: A model for mantle hydration and continental coverage. Planetary and Space Science 98, 5-13. [2] Kleidon, A., 2010. Life, hierarchy, and the thermodynamic machinery of planet Earth. Phys. Life Rev. 7, 428-460. [3] Rosing, M .T., et al., 2006. The rise of continents - an essay on the geologic consequences of photosynthesis. Paleogeogr., Paleoclimatol., Paleoecol. 232, 99-113. [4] Sleep, N.H., Bird, D.K., Pope, E., 2012. Paleontology of Earth's mantle. Annu. Rev. Earth Planet. Sci. 40, 277-300.

Earth applications of closed ecological systems: Relevance to the development of sustainability in our global biosphere

NASA Astrophysics Data System (ADS)

Nelson, M.; Allen, J.; Ailing, A.; Dempster, W. F.; Silverstone, S.

The parallels between the challenges facing bioregenerative life support in artificial closed ecological systems and those in our global biosphere are striking. At the scale of the current global technosphere and expanding human population, it is increasingly obvious that the biosphere can no longer safely buffer and absorb technogenic and anthropogenic pollutants. The loss of biodiversity, reliance on non-renewable natural resources, and conversion of once wild ecosystems for human use with attendant desertification/soil erosion, has led to a shift of consciousness and the widespread call for sustainability of human activities. For researchers working on bioregenerative life support in closed systems, the small volumes and faster cycling times than in the Earth's biosphere make it starkly clear that systems must be designed to ensure renewal of water and atmosphere, nutrient recycling, production of healthy food, and safe environmental methods of maintaining technical systems. The development of technical systems that can be fully integrated and supportive of living systems is a harbinger of new perspectives as well as technologies in the global environment. In addition, closed system bioregenerative life support offers opportunities for public education and consciousness changing of how to live with our global biosphere.

Global tropospheric methane: An indication of atmosphere-biosphere-climate interactions?

NASA Technical Reports Server (NTRS)

Harriss, Robert C.; Sebacher, Daniel I.; Bartlett, Karen B.

1985-01-01

Methane is an important atmospheric gas with potentially critical roles in both photochemical and radiation transfer processes. A major natural source of atmospheric methane involves anaerobic fermentation of organic materials in wetland soils and sediments. A data base of field measurements of atmospheric methane was used in the development of a global methane emissions inventory. Calculations support the following hypotheses: (1) Human activities currently produce methane at a rate approximately equal to natural resources (these rapidly increasing anthropogenic sources can explain most of the recent increase observed in tropospheric methane); and (2) Prior to 200 B.P. (before the present), the influence of climate on wetland extent and distribution was probably a dominant factor controlling global biogenic methane emissions to the atmosphere.

The Role of Biosphere Reserves in Environmental Education and Training = Le Role des reserves de la biosphere dans l'education et la formation environnementales. Report of the Unesco/MAB Symposium Held During the Unesco/UNEP International Congress on Environmental Education and Training (Moscow, USSR, August 17-21, 1987). Report 20.

ERIC Educational Resources Information Center

Francis, George, Ed.

Environmental education and training have been key elements of Unesco's Program on Man and the Biosphere (MAB) since its inception in 1971. The MAB Program is an intergovernmental program of research, training, demonstration and distribution of information, aimed at providing the scientific background and the trained personnel to deal with…

Ecology and exploration of the rare biosphere.

PubMed

Lynch, Michael D J; Neufeld, Josh D

2015-04-01

The profound influence of microorganisms on human life and global biogeochemical cycles underlines the value of studying the biogeography of microorganisms, exploring microbial genomes and expanding our understanding of most microbial species on Earth: that is, those present at low relative abundance. The detection and subsequent analysis of low-abundance microbial populations—the 'rare biosphere'—have demonstrated the persistence, population dynamics, dispersion and predation of these microbial species. We discuss the ecology of rare microbial populations, and highlight molecular and computational methods for targeting taxonomic 'blind spots' within the rare biosphere of complex microbial communities.

Ciliates and the rare biosphere: a review.

PubMed

Dunthorn, Micah; Stoeck, Thorsten; Clamp, John; Warren, Alan; Mahé, Frédéric

2014-01-01

Here we provide a brief review of the rare biosphere from the perspective of ciliates and other microbial eukaryotes. We trace research on rarity from its lack of much in-depth focus in morphological and Sanger sequencing projects, to its central importance in analyses using high throughput sequencing strategies. The problem that the rare biosphere is potentially comprised of mostly errors is then discussed in the light of asking community-comparative, novel-diversity, and ecosystem-functioning questions. © 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.

On the edge of a deep biosphere: Real animals in extreme environments

NASA Astrophysics Data System (ADS)

Childress, James J.; Fisher, Charles F.; Felbeck, Horst; Girguis, Peter

This paper considers the possibility of animals living in a subsurface environment on the global mid-ocean ridge system. It considers the possible environments and looks at the possibilities of animal inhabitants of the subsurface biosphere based on adaptations of animals to other extreme habitats. We conclude that there are known bridging inhabitants of the subsurface biosphere, that part-time inhabitants are extremely likely, and that there could be full-time inhabitants if conditions are stable within the tolerance limits of metazoans for time periods of months.

On the use of tower-flux measurements to assess the performance of global ecosystem models

NASA Astrophysics Data System (ADS)

El Maayar, M.; Kucharik, C.

2003-04-01

Global ecosystem models are important tools for the study of biospheric processes and their responses to environmental changes. Such models typically translate knowledge, gained from local observations, into estimates of regional or even global outcomes of ecosystem processes. A typical test of ecosystem models consists of comparing their output against tower-flux measurements of land surface-atmosphere exchange of heat and mass. To perform such tests, models are typically run using detailed information on soil properties (texture, carbon content,...) and vegetation structure observed at the experimental site (e.g., vegetation height, vegetation phenology, leaf photosynthetic characteristics,...). In global simulations, however, earth's vegetation is typically represented by a limited number of plant functional types (PFT; group of plant species that have similar physiological and ecological characteristics). For each PFT (e.g., temperate broadleaf trees, boreal conifer evergreen trees,...), which can cover a very large area, a set of typical physiological and physical parameters are assigned. Thus, a legitimate question arises: How does the performance of a global ecosystem model run using detailed site-specific parameters compare with the performance of a less detailed global version where generic parameters are attributed to a group of vegetation species forming a PFT? To answer this question, we used a multiyear dataset, measured at two forest sites with contrasting environments, to compare seasonal and interannual variability of surface-atmosphere exchange of water and carbon predicted by the Integrated BIosphere Simulator-Dynamic Global Vegetation Model. Two types of simulations were, thus, performed: a) Detailed runs: observed vegetation characteristics (leaf area index, vegetation height,...) and soil carbon content, in addition to climate and soil type, are specified for model run; and b) Generic runs: when only observed climates and soil types at the measurement sites are used to run the model. The generic runs were performed for the number of years equal to the current age of the forests, initialized with no vegetation and a soil carbon density equal to zero.

Victor Kovda, Soil Science and Biosphere

NASA Astrophysics Data System (ADS)

Kovda, I.

2012-04-01

Victor Kovda (1904-1991) was one of the most famous soil scientists at the national and international soil science community. He published more than 500 scientific works including about 400 papers, 17 collective monographs, 30 personal monographs, and more than 200 interviews and popular papers describing the role of soils not only for food production, but for the functioning of the biosphere. Victor Kovda was a talented organizer, who founded the new Institute of Soil Science and Agrochemistry (known at the present time as the Institute of physico-chemical and biological problems of soil science in Pushchino, Russia). During six years from 1959 to 1964 he was the head of Science Department in UNESCO, where he initiated a set of international projects (ex. Soil World Map of FAO-UNESCO, Source-book on irrigation and drainage). He continued his international activity after UNESCO as a President of the International Soil Science Society (1968-1974), organizer of the X international Soil Science Congress in Moscow (1974), president of SCOPE (1973-1976), working for ICSU. The last three decades of his national and international activities Victor Kovda initiated and was strongly involved in the popularization of biosphere role and functions of soils and soil cover. The start point for this activity was his special talk "Biosphere and man" presented during the intergovernmental conference in the framework of the international program "Man and Biosphere" organized by UNESCO in 1968 in Paris. The next key presentation "Soil as a component of biosphere" Victor Kovda gave as a plenary lecture during the X International congress of soil scientists. This presentation determined the focus of soil science for the next decades: at least Russian soil science became oriented towards the investigation of biosphere functions and role of soils. Soils science was accepted not only for agriculture and food production, but also as a fundamental science with a large environmental application.

The Search for Sustainable Subsurface Habitats on Mars, and the Sampling of Impact Ejecta

NASA Astrophysics Data System (ADS)

Ivarsson, Magnus; Lindgren, Paula

2010-07-01

On Earth, the deep subsurface biosphere of both the oceanic and the continental crust is well known for surviving harsh conditions and environments characterized by high temperatures, high pressures, extreme pHs, and the absence of sunlight. The microorganisms of the terrestrial deep biosphere have an excellent capacity for adapting to changing geochemistry, as the alteration of the crust proceeds and the conditions of their habitats slowly change. Despite an almost complete isolation from surface conditions and the surface biosphere, the deep biosphere of the crustal rocks has endured over geologic time. This indicates that the deep biosphere is a self-sufficient system, independent of the global events that occur at the surface, such as impacts, glaciations, sea level fluctuations, and climate changes. With our sustainable terrestrial subsurface biosphere in mind, the subsurface on Mars has often been suggested as the most plausible place to search for fossil Martian life, or even present Martian life. Since the Martian surface is more or less sterile, subsurface settings are the only place on Mars where life could have been sustained over geologic time. To detect a deep biosphere in the Martian basement, drilling is a requirement. However, near future Mars sample return missions are limited by the mission's payload, which excludes heavy drilling equipment and restrict the missions to only dig the topmost meter of the Martian soil. Therefore, the sampling and analysis of Martian impact ejecta has been suggested as a way of accessing the deeper Martian subsurface without using heavy drilling equipment. Impact cratering is a natural geological process capable of excavating and exposing large amounts of rock material from great depths up to the surface. Several studies of terrestrial impact deposits show the preservation of pre-impact biosignatures, such as fossilized organisms and chemical biological markers. Therefore, if the Martian subsurface contains a record of life, it is reasonable to assume that biosignatures derived from the Martian subsurface could also be preserved in the Martian impact ejecta.

Identifying dominant controls on hydrologic parameter transfer from gauged to ungauged catchments: a comparative hydrology approach

USGS Publications Warehouse

Singh, R.; Archfield, S.A.; Wagener, T.

2014-01-01

Daily streamflow information is critical for solving various hydrologic problems, though observations of continuous streamflow for model calibration are available at only a small fraction of the world’s rivers. One approach to estimate daily streamflow at an ungauged location is to transfer rainfall–runoff model parameters calibrated at a gauged (donor) catchment to an ungauged (receiver) catchment of interest. Central to this approach is the selection of a hydrologically similar donor. No single metric or set of metrics of hydrologic similarity have been demonstrated to consistently select a suitable donor catchment. We design an experiment to diagnose the dominant controls on successful hydrologic model parameter transfer. We calibrate a lumped rainfall–runoff model to 83 stream gauges across the United States. All locations are USGS reference gauges with minimal human influence. Parameter sets from the calibrated models are then transferred to each of the other catchments and the performance of the transferred parameters is assessed. This transfer experiment is carried out both at the scale of the entire US and then for six geographic regions. We use classification and regression tree (CART) analysis to determine the relationship between catchment similarity and performance of transferred parameters. Similarity is defined using physical/climatic catchment characteristics, as well as streamflow response characteristics (signatures such as baseflow index and runoff ratio). Across the entire US, successful parameter transfer is governed by similarity in elevation and climate, and high similarity in streamflow signatures. Controls vary for different geographic regions though. Geology followed by drainage, topography and climate constitute the dominant similarity metrics in forested eastern mountains and plateaus, whereas agricultural land use relates most strongly with successful parameter transfer in the humid plains.

Pilot Institute on Global Change on Trace Gases and the Biosphere, 1988

NASA Technical Reports Server (NTRS)

Eddy, J. A.; Moore, B.

1998-01-01

Table of Contents: Summary; Background; General Framework for a Series of Institutes on Global Change; The 1988 Pilot Institute on Global Changes: Trace Gases and the Biosphere; Budget; List of Acronyms; and Attachments.

Closed ecological systems: From test tubes to Earth's biosphere

NASA Technical Reports Server (NTRS)

Frye, Robert J.; Mignon, George

1992-01-01

Artificially constructed closed ecological systems (CES) have been researched both experimentally and theoretically for over 25 years. The size of these systems have varied from less than one liter to many thousands of cubic meters in volume. The diversity of the included components has a similarly wide range from purely aquatic systems to soil based systems that incorporate many aspects of Earth's biosphere. While much has been learned about the functioning of these closed systems, much remains to be learned. In this paper, we compare and contrast the behavior of closed ecological systems of widely different sizes through an analysis of their atmospheric composition. In addition, we will compare the performance of relatively small CES with the behavior of Earth's biosphere. We address the applicability of small CES as replicable analogs for planetary biospheres and discuss the use of small CES as an experimental milieu for an examination of the evolution of extra-terrestrial colonies.

In situ Detection of Microbial Life in the Deep Biosphere in Igneous Ocean Crust

PubMed Central

Salas, Everett C.; Bhartia, Rohit; Anderson, Louise; Hug, William F.; Reid, Ray D.; Iturrino, Gerardo; Edwards, Katrina J.

2015-01-01

The deep biosphere is a major frontier to science. Recent studies have shown the presence and activity of cells in deep marine sediments and in the continental deep biosphere. Volcanic lavas in the deep ocean subsurface, through which substantial fluid flow occurs, present another potentially massive deep biosphere. We present results from the deployment of a novel in situ logging tool designed to detect microbial life harbored in a deep, native, borehole environment within igneous oceanic crust, using deep ultraviolet native fluorescence spectroscopy. Results demonstrate the predominance of microbial-like signatures within the borehole environment, with densities in the range of 105 cells/mL. Based on transport and flux models, we estimate that such a concentration of microbial cells could not be supported by transport through the crust, suggesting in situ growth of these communities. PMID:26617595

Gene expression in the deep biosphere.

PubMed

Orsi, William D; Edgcomb, Virginia P; Christman, Glenn D; Biddle, Jennifer F

2013-07-11

Scientific ocean drilling has revealed a deep biosphere of widespread microbial life in sub-seafloor sediment. Microbial metabolism in the marine subsurface probably has an important role in global biogeochemical cycles, but deep biosphere activities are not well understood. Here we describe and analyse the first sub-seafloor metatranscriptomes from anaerobic Peru Margin sediment up to 159 metres below the sea floor, represented by over 1 billion complementary DNA (cDNA) sequence reads. Anaerobic metabolism of amino acids, carbohydrates and lipids seem to be the dominant metabolic processes, and profiles of dissimilatory sulfite reductase (dsr) transcripts are consistent with pore-water sulphate concentration profiles. Moreover, transcripts involved in cell division increase as a function of microbial cell concentration, indicating that increases in sub-seafloor microbial abundance are a function of cell division across all three domains of life. These data support calculations and models of sub-seafloor microbial metabolism and represent the first holistic picture of deep biosphere activities.

Community Assembly Processes of the Microbial Rare Biosphere.

PubMed

Jia, Xiu; Dini-Andreote, Francisco; Falcão Salles, Joana

2018-03-14

Our planet teems with microorganisms that often present a skewed abundance distribution in a local community, with relatively few dominant species coexisting alongside a high number of rare species. Recent studies have demonstrated that these rare taxa serve as limitless reservoirs of genetic diversity, and perform disproportionate types of functions despite their low abundances. However, relatively little is known about the mechanisms controlling rarity and the processes promoting the development of the rare biosphere. Here, we propose the use of multivariate cut-offs to estimate rare species and phylogenetic null models applied to predefined rare taxa to disentangle the relative influences of ecoevolutionary processes mediating the assembly of the rare biosphere. Importantly, the identification of the factors controlling rare species assemblages is critical for understanding the types of rarity, how the rare biosphere is established, and how rare microorganisms fluctuate over spatiotemporal scales, thus enabling prospective predictions of ecosystem responses. Copyright © 2018 Elsevier Ltd. All rights reserved.

Scientific Discovery through Advanced Computing (SciDAC-3) Partnership Project Annual Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoffman, Forest M.; Bochev, Pavel B.; Cameron-Smith, Philip J..

The Applying Computationally Efficient Schemes for BioGeochemical Cycles ACES4BGC Project is advancing the predictive capabilities of Earth System Models (ESMs) by reducing two of the largest sources of uncertainty, aerosols and biospheric feedbacks, with a highly efficient computational approach. In particular, this project is implementing and optimizing new computationally efficient tracer advection algorithms for large numbers of tracer species; adding important biogeochemical interactions between the atmosphere, land, and ocean models; and applying uncertainty quanti cation (UQ) techniques to constrain process parameters and evaluate uncertainties in feedbacks between biogeochemical cycles and the climate system.

Characterizing biospheric carbon balance using CO2 observations from the OCO-2 satellite

NASA Astrophysics Data System (ADS)

Miller, Scot M.; Michalak, Anna M.; Yadav, Vineet; Tadić, Jovan M.

2018-05-01

NASA's Orbiting Carbon Observatory 2 (OCO-2) satellite launched in summer of 2014. Its observations could allow scientists to constrain CO2 fluxes across regions or continents that were previously difficult to monitor. This study explores an initial step toward that goal; we evaluate the extent to which current OCO-2 observations can detect patterns in biospheric CO2 fluxes and constrain monthly CO2 budgets. Our goal is to guide top-down, inverse modeling studies and identify areas for future improvement. We find that uncertainties and biases in the individual OCO-2 observations are comparable to the atmospheric signal from biospheric fluxes, particularly during Northern Hemisphere winter when biospheric fluxes are small. A series of top-down experiments indicate how these errors affect our ability to constrain monthly biospheric CO2 budgets. We are able to constrain budgets for between two and four global regions using OCO-2 observations, depending on the month, and we can constrain CO2 budgets at the regional level (i.e., smaller than seven global biomes) in only a handful of cases (16 % of all regions and months). The potential of the OCO-2 observations, however, is greater than these results might imply. A set of synthetic data experiments suggests that retrieval errors have a salient effect. Advances in retrieval algorithms and to a lesser extent atmospheric transport modeling will improve the results. In the interim, top-down studies that use current satellite observations are best-equipped to constrain the biospheric carbon balance across only continental or hemispheric regions.

Carbon 13 exchanges between the atmosphere and biosphere

NASA Astrophysics Data System (ADS)

Fung, I.; Field, C. B.; Berry, J. A.; Thompson, M. V.; Randerson, J. T.; MalmströM, C. M.; Vitousek, P. M.; Collatz, G. James; Sellers, P. J.; Randall, D. A.; Denning, A. S.; Badeck, F.; John, J.

1997-12-01

We present a detailed investigation of the gross 12C and 13C exchanges between the atmosphere and biosphere and their influence on the δ13C variations in the atmosphere. The photosynthetic discrimination Δ against 13C is derived from a biophysical model coupled to a general circulation model [Sellers et al., 1996a], where stomatal conductance and carbon assimilation are determined simultaneously with the ambient climate. The δ13C of the respired carbon is calculated by a biogeochemical model [Potter et al., 1993; Randerson et al., 1996] as the sum of the contributions from compartments with varying ages. The global flux-weighted mean photosynthetic discrimination is 12-16‰, which is lower than previous estimates. Factors that lower the discrimination are reduced stomatal conductance and C4 photosynthesis. The decreasing atmospheric δ13C causes an isotopic disequilibrium between the outgoing and incoming fluxes; the disequilibrium is ˜0.33‰ for 1988. The disequilibrium is higher than previous estimates because it accounts for the lifetime of trees and for the ages rather than turnover times of the biospheric pools. The atmospheric δ13C signature resulting from the biospheric fluxes is investigated using a three-dimensional atmospheric tracer model. The isotopic disequilibrium alone produces a hemispheric difference of ˜0.02‰ in atmospheric δ13C, comparable to the signal from a hypothetical carbon sink of 0.5 Gt C yr-1 into the midlatitude northern hemisphere biosphere. However, the rectifier effect, due to the seasonal covariation of CO2 fluxes and height of the atmospheric boundary layer, yields a background δ13C gradient of the opposite sign. These effects nearly cancel thus favoring a stronger net biospheric uptake than without the background CO2 gradient. Our analysis of the globally averaged carbon budget for the decade of the 1980s indicates that the biospheric uptake of fossil fuel CO2 is likely to be greater than the oceanic uptake; the relative proportions of the sinks cannot be uniquely determined using 12C and 13C alone. The land-ocean sink partitioning requires, in addition, information about the land use source, isotopic disequilibrium associated with gross oceanic exchanges, as well as the fractions of C3 and C4 vegetation involved in the biospheric uptake.

Exploring global carbon turnover and radiocarbon cycling in terrestrial biosphere models

NASA Astrophysics Data System (ADS)

Graven, H. D.; Warren, H.

2017-12-01

The uptake of carbon into terrestrial ecosystems through net primary productivity (NPP) and the turnover of that carbon through various pathways are the fundamental drivers of changing carbon stocks on land, in addition to human-induced and natural disturbances. Terrestrial biosphere models use different formulations for carbon uptake and release, resulting in a range of values in NPP of 40-70 PgC/yr and biomass turnover times of about 25-40 years for the preindustrial period in current-generation models from CMIP5. Biases in carbon uptake and turnover impact simulated carbon uptake and storage in the historical period and later in the century under changing climate and CO2 concentration, however evaluating global-scale NPP and carbon turnover is challenging. Scaling up of plot-scale measurements involves uncertainty due to the large heterogeneity across ecosystems and biomass types, some of which are not well-observed. We are developing the modelling of radiocarbon in terrestrial biosphere models, with a particular focus on decadal 14C dynamics after the nuclear weapons testing in the 1950s-60s, including the impact of carbon flux trends and variability on 14C cycling. We use an estimate of the total inventory of excess 14C in the biosphere constructed by Naegler and Levin (2009) using a 14C budget approach incorporating estimates of total 14C produced by the weapons tests and atmospheric and oceanic 14C observations. By simulating radiocarbon in simple biosphere box models using carbon fluxes from the CMIP5 models, we find that carbon turnover is too rapid in many of the simple models - the models appear to take up too much 14C and release it too quickly. Therefore many CMIP5 models may also simulate carbon turnover that is too rapid. A caveat is that the simple box models we use may not adequately represent carbon dynamics in the full-scale models. Explicit simulation of radiocarbon in terrestrial biosphere models would allow more robust evaluation of biosphere models and the investigation of climate-carbon cycle feedbacks on various timescales. Explicit simulation of radiocarbon and carbon-13 in terrestrial biosphere models of Earth System Models, as well as in ocean models, is recommended by CMIP6 and supported by CMIP6 protocols and forcing datasets.

Regression analysis and transfer function in estimating the parameters of central pulse waves from brachial pulse wave.

PubMed

Chai Rui; Li Si-Man; Xu Li-Sheng; Yao Yang; Hao Li-Ling

2017-07-01

This study mainly analyzed the parameters such as ascending branch slope (A_slope), dicrotic notch height (Hn), diastolic area (Ad) and systolic area (As) diastolic blood pressure (DBP), systolic blood pressure (SBP), pulse pressure (PP), subendocardial viability ratio (SEVR), waveform parameter (k), stroke volume (SV), cardiac output (CO) and peripheral resistance (RS) of central pulse wave invasively and non-invasively measured. These parameters extracted from the central pulse wave invasively measured were compared with the parameters measured from the brachial pulse waves by a regression model and a transfer function model. The accuracy of the parameters which were estimated by the regression model and the transfer function model was compared too. Our findings showed that in addition to the k value, the above parameters of the central pulse wave and the brachial pulse wave invasively measured had positive correlation. Both the regression model parameters including A_slope, DBP, SEVR and the transfer function model parameters had good consistency with the parameters invasively measured, and they had the same effect of consistency. The regression equations of the three parameters were expressed by Y'=a+bx. The SBP, PP, SV, CO of central pulse wave could be calculated through the regression model, but their accuracies were worse than that of transfer function model.

Consistent Parameter and Transfer Function Estimation using Context Free Grammars

NASA Astrophysics Data System (ADS)

Klotz, Daniel; Herrnegger, Mathew; Schulz, Karsten

2017-04-01

This contribution presents a method for the inference of transfer functions for rainfall-runoff models. Here, transfer functions are defined as parametrized (functional) relationships between a set of spatial predictors (e.g. elevation, slope or soil texture) and model parameters. They are ultimately used for estimation of consistent, spatially distributed model parameters from a limited amount of lumped global parameters. Additionally, they provide a straightforward method for parameter extrapolation from one set of basins to another and can even be used to derive parameterizations for multi-scale models [see: Samaniego et al., 2010]. Yet, currently an actual knowledge of the transfer functions is often implicitly assumed. As a matter of fact, for most cases these hypothesized transfer functions can rarely be measured and often remain unknown. Therefore, this contribution presents a general method for the concurrent estimation of the structure of transfer functions and their respective (global) parameters. Note, that by consequence an estimation of the distributed parameters of the rainfall-runoff model is also undertaken. The method combines two steps to achieve this. The first generates different possible transfer functions. The second then estimates the respective global transfer function parameters. The structural estimation of the transfer functions is based on the context free grammar concept. Chomsky first introduced context free grammars in linguistics [Chomsky, 1956]. Since then, they have been widely applied in computer science. But, to the knowledge of the authors, they have so far not been used in hydrology. Therefore, the contribution gives an introduction to context free grammars and shows how they can be constructed and used for the structural inference of transfer functions. This is enabled by new methods from evolutionary computation, such as grammatical evolution [O'Neill, 2001], which make it possible to exploit the constructed grammar as a search space for equations. The parametrization of the transfer functions is then achieved through a second optimization routine. The contribution explores different aspects of the described procedure through a set of experiments. These experiments can be divided into three categories: (1) The inference of transfer functions from directly measurable parameters; (2) The estimation of global parameters for given transfer functions from runoff data; and (3) The estimation of sets of completely unknown transfer functions from runoff data. The conducted tests reveal different potentials and limits of the procedure. In concrete it is shown that example (1) and (2) work remarkably well. Example (3) is much more dependent on the setup. In general, it can be said that in that case much more data is needed to derive transfer function estimations, even for simple models and setups. References: - Chomsky, N. (1956): Three Models for the Description of Language. IT IRETr. 2(3), p 113-124 - O'Neil, M. (2001): Grammatical Evolution. IEEE ToEC, Vol.5, No. 4 - Samaniego, L.; Kumar, R.; Attinger, S. (2010): Multiscale parameter regionalization of a grid-based hydrologic model at the mesoscale. WWR, Vol. 46, W05523, doi:10.1029/2008WR007327

Advanced Pressure Coring System for Deep Earth Sampling (APRECOS)

NASA Astrophysics Data System (ADS)

Anders, E.; Rothfuss, M.; Müller, W. H.

2009-04-01

Nowadays the recovery of cores from boreholes is a standard operation. However, during that process the mechanical, physical, and chemical properties as well as living conditions for microorganisms are significantly altered. In-situ sampling is one approach to overcome the severe scientific limitations of conventional, depressurized core investigations by recovering, processing, and conducting experiments in the laboratory, while maintaining unchanged environmental parameters. The most successful equipment today is the suite of tools developed within the EU funded projects HYACE (Hydrate Autoclave Coring Equipment) and HYACINTH (Deployment of HYACE tools In New Tests on Hydrates) between 1997 and 2005. Within several DFG (German Research Foundation) projects the Technical University Berlin currently works on concepts to increase the present working pressure of 250 bar as well as to reduce logistical and financial expenses by merging redundant and analogous procedures and scaling down the considerable size of key components. It is also proposed to extend the range of applications for the wireline rotary pressure corer and the sub-sampling and transfer system to all types of soil conditions (soft to highly-consolidated). New modifications enable the tools to be used in other pressure related fields of research, such as unconventional gas exploration (coal-bed methane, tight gas, gas hydrate), CO2 sequestration, and microbiology of the deep biosphere. Expedient enhancement of an overall solution for pressure core retrieval, process and investigation will open the way for a complete on-site, all-purpose, in-situ equipment. The advanced assembly would allow for executing the whole operation sequences of coring, non-destructive measurement, sub-sampling and transfer into storage, measurement and transportation chambers, all in sterile, anaerobic conditions, and without depressurisation in quick succession. Extensive post-cruise handling and interim storage would be dispensable. The complete core processing and preparation of in-situ sample sections for worldwide shipping could be conducted within hours after retrieval.

Reviews and syntheses: to the bottom of carbon processing at the seafloor

NASA Astrophysics Data System (ADS)

Middelburg, Jack J.

2018-01-01

Organic carbon processing at the seafloor is studied by biogeochemists to quantify burial and respiration, by organic geochemists to elucidate compositional changes and by ecologists to follow carbon transfers within food webs. Here I review these disciplinary approaches and discuss where they agree and disagree. It will be shown that the biogeochemical approach (ignoring the identity of organisms) and the ecological approach (focussing on growth and biomass of organisms) are consistent on longer timescales. Secondary production by microbes and animals is identified to potentially impact the composition of sedimentary organic matter. Animals impact sediment organic carbon processing by microbes in multiple ways: by governing organic carbon supply to sediments, by aeration via bio-irrigation and by mixing labile organic matter to deeper layers. I will present an inverted microbial loop in which microbes profit from bioturbation rather than animals profiting from microbial processing of otherwise lost dissolved organic resources. Sediments devoid of fauna therefore function differently and are less efficient in processing organic matter with the consequence that more organic matter is buried and transferred from Vernadsky's biosphere to the geosphere.

C-DEBI Community College Research Internship for Scientific Engagement: Effective Practices in Running a Non-Residential Research Program

NASA Astrophysics Data System (ADS)

Schroeder, S.

2016-02-01

The Center For Dark Energy Biosphere Investigations (C-DEBI), an NSF Science and Technology Center, is located in the heart of Los Angeles, surrounded by nineteen community colleges. C-DEBI recognizes the community college student as an untapped STEM resource and piloted the Community College Research Internship for Scientific Engagement (CC-RISE) in 2013. A non-residential, research-focused summer internship, the successful program expanded to UC-Santa Cruz and the Marine Biological Laboratory in 2014 and 2015, respectively. A non-residential research program gives students who are often first generation or non-traditional a stepping stone to experience the research environment while reducing transfer shock. Formal evaluation of CC-RISE indicates that in addition to providing an immersive research experience for community college students, the key components to running a successful non-residential program include weekly informal meetings to allow the students to create a cohort, as well as program aspects dedicated to professional development topics such as the transfer process and using resources at 4-year institutions to maximize success.

DOE Office of Scientific and Technical Information (OSTI.GOV)

N.D. Francis

The objective of this calculation is to develop a time dependent in-drift effective thermal conductivity parameter that will approximate heat conduction, thermal radiation, and natural convection heat transfer using a single mode of heat transfer (heat conduction). In order to reduce the physical and numerical complexity of the heat transfer processes that occur (and must be modeled) as a result of the emplacement of heat generating wastes, a single parameter will be developed that approximates all forms of heat transfer from the waste package surface to the drift wall (or from one surface exchanging heat with another). Subsequently, with thismore » single parameter, one heat transfer mechanism (e.g., conduction heat transfer) can be used in the models. The resulting parameter is to be used as input in the drift-scale process-level models applied in total system performance assessments for the site recommendation (TSPA-SR). The format of this parameter will be a time-dependent table for direct input into the thermal-hydrologic (TH) and the thermal-hydrologic-chemical (THC) models.« less

Tracking the ecological overshoot of the human economy

PubMed Central

Wackernagel, Mathis; Schulz, Niels B.; Deumling, Diana; Linares, Alejandro Callejas; Jenkins, Martin; Kapos, Valerie; Monfreda, Chad; Loh, Jonathan; Myers, Norman; Norgaard, Richard; Randers, Jørgen

2002-01-01

Sustainability requires living within the regenerative capacity of the biosphere. In an attempt to measure the extent to which humanity satisfies this requirement, we use existing data to translate human demand on the environment into the area required for the production of food and other goods, together with the absorption of wastes. Our accounts indicate that human demand may well have exceeded the biosphere's regenerative capacity since the 1980s. According to this preliminary and exploratory assessment, humanity's load corresponded to 70% of the capacity of the global biosphere in 1961, and grew to 120% in 1999. PMID:12089326

Earth applications of closed ecological systems: relevance to the development of sustainability in our global biosphere.

PubMed

Nelson, M; Allen, J; Alling, A; Dempster, W F; Silverstone, S

2003-01-01

The parallels between the challenges facing bioregenerative life support in artificial closed ecological systems and those in our global biosphere are striking. At the scale of the current global technosphere and expanding human population, it is increasingly obvious that the biosphere can no longer safely buffer and absorb technogenic and anthropogenic pollutants. The loss of biodiversity, reliance on non-renewable natural resources, and conversion of once wild ecosystems for human use with attendant desertification/soil erosion, has led to a shift of consciousness and the widespread call for sustainability of human activities. For researchers working on bioregenerative life support in closed systems, the small volumes and faster cycling times than in the Earth's biosphere make it starkly clear that systems must be designed to ensure renewal of water and atmosphere, nutrient recycling, production of healthy food, and safe environmental methods of maintaining technical systems. The development of technical systems that can be fully integrated and supportive of living systems is a harbinger of new perspectives as well as technologies in the global environment. In addition, closed system bioregenerative life support offers opportunities for public education and consciousness changing of how to live with our global biosphere. c2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Space Microbiology

PubMed Central

Horneck, Gerda; Klaus, David M.; Mancinelli, Rocco L.

2010-01-01

Summary: The responses of microorganisms (viruses, bacterial cells, bacterial and fungal spores, and lichens) to selected factors of space (microgravity, galactic cosmic radiation, solar UV radiation, and space vacuum) were determined in space and laboratory simulation experiments. In general, microorganisms tend to thrive in the space flight environment in terms of enhanced growth parameters and a demonstrated ability to proliferate in the presence of normally inhibitory levels of antibiotics. The mechanisms responsible for the observed biological responses, however, are not yet fully understood. A hypothesized interaction of microgravity with radiation-induced DNA repair processes was experimentally refuted. The survival of microorganisms in outer space was investigated to tackle questions on the upper boundary of the biosphere and on the likelihood of interplanetary transport of microorganisms. It was found that extraterrestrial solar UV radiation was the most deleterious factor of space. Among all organisms tested, only lichens (Rhizocarpon geographicum and Xanthoria elegans) maintained full viability after 2 weeks in outer space, whereas all other test systems were inactivated by orders of magnitude. Using optical filters and spores of Bacillus subtilis as a biological UV dosimeter, it was found that the current ozone layer reduces the biological effectiveness of solar UV by 3 orders of magnitude. If shielded against solar UV, spores of B. subtilis were capable of surviving in space for up to 6 years, especially if embedded in clay or meteorite powder (artificial meteorites). The data support the likelihood of interplanetary transfer of microorganisms within meteorites, the so-called lithopanspermia hypothesis. PMID:20197502

Geobiochemistry of metabolism: Standard state thermodynamic properties of the citric acid cycle

NASA Astrophysics Data System (ADS)

Canovas, Peter A.; Shock, Everett L.

2016-12-01

Integrating microbial metabolism into geochemical modeling allows assessments of energy and mass transfer between the geosphere and the microbial biosphere. Energy and power supplies and demands can be assessed from analytical geochemical data given thermodynamic data for compounds involved in catabolism and anabolism. Results are reported here from a critique of the available standard state thermodynamic data for organic acids and acid anions involved in the citric acid cycle (also known as the tricarboxylic acid cycle or the Krebs cycle). The development of methods for estimating standard state data unavailable from experiments is described, together with methods to predict corresponding values at elevated temperatures and pressures using the revised Helgeson-Kirkham-Flowers (HKF) equation of state for aqueous species. Internal consistency is maintained with standard state thermodynamic data for organic and inorganic aqueous species commonly used in geochemical modeling efforts. Standard state data and revised-HKF parameters are used to predict equilibrium dissociation constants for the organic acids in the citric acid cycle, and to assess standard Gibbs energies of reactions for each step in the cycle at elevated temperatures and pressures. The results presented here can be used with analytical data from natural and experimental systems to assess the energy and power demands of microorganisms throughout the habitable ranges of pressure and temperature, and to assess the consequences of abiotic organic compound alteration processes at conditions of subsurface aquifers, sedimentary basins, hydrothermal systems, meteorite parent bodies, and ocean worlds throughout the solar system.

Interaction between Hydrosphere and Biosphere: Challenges and Opportunities

NASA Astrophysics Data System (ADS)

Kumar, P.; Sivapalan, M.

2007-12-01

Vegetated terrestrial ecosystems and the overlying atmosphere are dynamically linked though the continuous transfer of mass, energy and momentum. The hydrologic variability interacts with the vegetation at time scales ranging from hours to days to inter-annual and decadal. The existing distribution of ecosystems is a result of evolutionary selections in response to environmental constraints which are themselves modified as terrestrial systems evolve until reaching a dynamic equilibrium. However this balance is changing, often rapidly, in response to anthropogenic influences such as climate change, land use/land cover change, and urban and agricultural expansions. Evidence suggests that vegetation response is adaptive in that they alter their survival strategies in response to environmental change, for example, through development of deep rooting and using hydraulic redistribution to better utilize the available moisture in the deeper soil layers. Yet little is known on how this impacts the hydrologic cycle and its variability. Active and adaptive control of vegetation and atmospheric flow moves soil-moisture that is no longer constrained by watershed boundaries. How do the atmospheric and terrestrial moisture, and vegetation interact to produce the observed variability in the water cycle and how does/will this variability change in response to the anthropogenic influences? What are the ecological consequences of this change? These broad questions lie at the heart of understanding the interaction between the hydrosphere and biosphere. Some specific questions to address are: · How does biosphere mediate the interaction between long time scale sub-surface hydrology and short time scale atmospheric hydrologic cycle? · How has this interaction given rise to the observed self-organized patterns of ecosystems and how do these ecosystems sustain the hydrologic regime needed for their own sustenance? · How are the dynamic regimes of ecohydrologic interactions affected by the anthropogenic impacts of land use/land cover change, elevated CO2 and temperature, water use, etc? · How do these linkages and changes there in alter the biogeochemical cycling in a region? Addressing these challenges is a sub-theme of the synthesis project supported by NSF. In this talk we will describe the progress made in regard to these issues.

Solar influences on global change

NASA Technical Reports Server (NTRS)

1994-01-01

Monitoring of the Sun and the Earth has yielded new knowledge essential to this debate. There is now no doubt that the total radiative energy from the Sun that heats the Earth's surface changes over decadal time scales as a consequence of solar activity. Observations indicate as well that changes in ultraviolet radiation and energetic particles from the Sun, also connected with the solar activity, modulate the layer of ozone that protects the biosphere from the solar ultraviolet radiation. This report reassesses solar influences on global change in the light of this new knowledge of solar and atmospheric variability. Moreover, the report considers climate change to be encompassed within the broader concept of global change; thus the biosphere is recognized to be part of a larger, coupled Earth system. Implementing a program to continuously monitor solar irradiance over the next several decades will provide the opportunity to estimate solar influences on global change, assuming continued maintenance of observations of climate and other potential forcing mechanisms. In the lower atmosphere, an increase in solar radiation is expected to cause global warming. In the stratosphere, however, the two effects produce temperature changes of opposite sign. A monitoring program that would augment long term observations of tropospheric parameters with similar observations of stratospheric parameters could separate these diverse climate perturbations and perhaps isolate a greenhouse footprint of climate change. Monitoring global change in the troposphere is a key element of all facets of the United States Global Change Research Program (USGCRP), not just of the study of solar influences on global change. The need for monitoring the stratosphere is also important for global change research in its own right because of the stratospheric ozone layer.

Description, calibration and sensitivity analysis of the local ecosystem submodel of a global model of carbon and nitrogen cycling and the water balance in the terrestrial biosphere

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kercher, J.R.; Chambers, J.Q.

1995-10-01

We have developed a geographically-distributed ecosystem model for the carbon, nitrogen, and water dynamics of the terrestrial biosphere TERRA. The local ecosystem model of TERRA consists of coupled, modified versions of TEM and DAYTRANS. The ecosystem model in each grid cell calculates water fluxes of evaporation, transpiration, and runoff; carbon fluxes of gross primary productivity, litterfall, and plant and soil respiration; and nitrogen fluxes of vegetation uptake, litterfall, mineralization, immobilization, and system loss. The state variables are soil water content; carbon in live vegetation; carbon in soil; nitrogen in live vegetation; organic nitrogen in soil and fitter; available inorganic nitrogenmore » aggregating nitrites, nitrates, and ammonia; and a variable for allocation. Carbon and nitrogen dynamics are calibrated to specific sites in 17 vegetation types. Eight parameters are determined during calibration for each of the 17 vegetation types. At calibration, the annual average values of carbon in vegetation C, show site differences that derive from the vegetation-type specific parameters and intersite variation in climate and soils. From calibration, we recover the average C{sub v} of forests, woodlands, savannas, grasslands, shrublands, and tundra that were used to develop the model initially. The timing of the phases of the annual variation is driven by temperature and light in the high latitude and moist temperate zones. The dry temperate zones are driven by temperature, precipitation, and light. In the tropics, precipitation is the key variable in annual variation. The seasonal responses are even more clearly demonstrated in net primary production and show the same controlling factors.« less

Modeling pN2 through Geological Time: Implications for Planetary Climates and Atmospheric Biosignatures.

PubMed

Stüeken, E E; Kipp, M A; Koehler, M C; Schwieterman, E W; Johnson, B; Buick, R

2016-12-01

Nitrogen is a major nutrient for all life on Earth and could plausibly play a similar role in extraterrestrial biospheres. The major reservoir of nitrogen at Earth's surface is atmospheric N 2 , but recent studies have proposed that the size of this reservoir may have fluctuated significantly over the course of Earth's history with particularly low levels in the Neoarchean-presumably as a result of biological activity. We used a biogeochemical box model to test which conditions are necessary to cause large swings in atmospheric N 2 pressure. Parameters for our model are constrained by observations of modern Earth and reconstructions of biomass burial and oxidative weathering in deep time. A 1-D climate model was used to model potential effects on atmospheric climate. In a second set of tests, we perturbed our box model to investigate which parameters have the greatest impact on the evolution of atmospheric pN 2 and consider possible implications for nitrogen cycling on other planets. Our results suggest that (a) a high rate of biomass burial would have been needed in the Archean to draw down atmospheric pN 2 to less than half modern levels, (b) the resulting effect on temperature could probably have been compensated by increasing solar luminosity and a mild increase in pCO 2 , and (c) atmospheric oxygenation could have initiated a stepwise pN 2 rebound through oxidative weathering. In general, life appears to be necessary for significant atmospheric pN 2 swings on Earth-like planets. Our results further support the idea that an exoplanetary atmosphere rich in both N 2 and O 2 is a signature of an oxygen-producing biosphere. Key Words: Biosignatures-Early Earth-Planetary atmospheres. Astrobiology 16, 949-963.

Group dynamics challenges: Insights from Biosphere 2 experiments

NASA Astrophysics Data System (ADS)

Nelson, Mark; Gray, Kathelin; Allen, John P.

2015-07-01

Successfully managing group dynamics of small, physically isolated groups is vital for long duration space exploration/habitation and for terrestrial CELSS (Controlled Environmental Life Support System) facilities with human participants. Biosphere 2 had important differences and shares some key commonalities with both Antarctic and space environments. There were a multitude of stress factors during the first two year closure experiment as well as mitigating factors. A helpful tool used at Biosphere 2 was the work of W.R. Bion who identified two competing modalities of behavior in small groups. Task-oriented groups are governed by conscious acceptance of goals, reality-thinking in relation to time and resources, and intelligent management of challenges. The opposing unconscious mode, the "basic-assumption" ("group animal") group, manifests through Dependency/Kill the Leader, Fight/Flight and Pairing. These unconscious dynamics undermine and can defeat the task group's goal. The biospherians experienced some dynamics seen in other isolated teams: factions developing reflecting personal chemistry and disagreements on overall mission procedures. These conflicts were exacerbated by external power struggles which enlisted support of those inside. Nevertheless, the crew evolved a coherent, creative life style to deal with some of the deprivations of isolation. The experience of the first two year closure of Biosphere 2 vividly illustrates both vicissitudes and management of group dynamics. The crew overrode inevitable frictions to creatively manage both operational and research demands and opportunities of the facility, thus staying 'on task' in Bion's group dynamics terminology. The understanding that Biosphere 2 was their life support system may also have helped the mission to succeed. Insights from the Biosphere 2 experience can help space and remote missions cope successfully with the inherent challenges of small, isolated crews.

The Effects of Nitrogen Fertilization of a Corn Ecosystem's Oxidative Ratio and Its Carbon Cycle Implications

NASA Astrophysics Data System (ADS)

Gallagher, M. E.; Masiello, C. A.; Hockaday, W. C.; McSwiney, C. P.; Robertson, G. P.

2008-12-01

One of the most effective ways to estimate the size of carbon sinks in the terrestrial biosphere and oceans is through paired measurements of atmospheric CO2 and O2 concentrations (e.g. (Keeling et al. 1996)). Successful use of this technique requires knowledge of the oxidative ratio (OR) of the terrestrial biosphere (the ratio of moles of O2 released per moles of CO2 consumed in gas fluxes between the terrestrial biosphere and atmosphere.) Historically the terrestrial biosphere's OR has been assumed to be a constant, approximately 1.1 (e.g. Prentice et al. 2001). However, small shifts in the biosphere's OR values can lead to large variations in the calculated sizes of the terrestrial biosphere and ocean carbon sinks (Randerson et al. 2006). We have recently shown that it is possible to measure the OR of biomass to at least +/- 0.01 units (Masiello et al., 2008), and that there is significant natural variability in ecosystem OR. Ecosystem OR is impacted by human activities. In this presentation, we explore the effects of one major form of anthropogenic ecosystem alteration: nitrogen fertilization. We are measuring ecosystem OR in corn agricultural ecosystems under a range of nitrogen fertilization treatments at the Kellogg Biological Station- Long Term Ecological Research Site (KBS-LTER) in Michigan. We measure OR indirectly, through its relationship with organic carbon oxidation state (Cox) (Masiello et al. 2008). Here we present data showing the effects of varying corn ecosystem nitrogen fertilization rates (from 0 to 202 kg N/ha) on ecosystem OR and the implications it will have on apportionment calculations.

An improved land biosphere module for use in the DCESS Earth system model (version 1.1) with application to the last glacial termination

NASA Astrophysics Data System (ADS)

Eichinger, Roland; Shaffer, Gary; Albarrán, Nelson; Rojas, Maisa; Lambert, Fabrice

2017-09-01

Interactions between the land biosphere and the atmosphere play an important role for the Earth's carbon cycle and thus should be considered in studies of global carbon cycling and climate. Simple approaches are a useful first step in this direction but may not be applicable for certain climatic conditions. To improve the ability of the reduced-complexity Danish Center for Earth System Science (DCESS) Earth system model DCESS to address cold climate conditions, we reformulated the model's land biosphere module by extending it to include three dynamically varying vegetation zones as well as a permafrost component. The vegetation zones are formulated by emulating the behaviour of a complex land biosphere model. We show that with the new module, the size and timing of carbon exchanges between atmosphere and land are represented more realistically in cooling and warming experiments. In particular, we use the new module to address carbon cycling and climate change across the last glacial transition. Within the constraints provided by various proxy data records, we tune the DCESS model to a Last Glacial Maximum state and then conduct transient sensitivity experiments across the transition under the application of explicit transition functions for high-latitude ocean exchange, atmospheric dust, and the land ice sheet extent. We compare simulated time evolutions of global mean temperature, pCO2, atmospheric and oceanic carbon isotopes as well as ocean dissolved oxygen concentrations with proxy data records. In this way we estimate the importance of different processes across the transition with emphasis on the role of land biosphere variations and show that carbon outgassing from permafrost and uptake of carbon by the land biosphere broadly compensate for each other during the temperature rise of the early last deglaciation.

Towards understanding the variability in biospheric CO2 fluxes: using FTIR spectrometry and a chemical transport model to investigate the sources and sinks of carbonyl sulfide and its link to CO2

NASA Astrophysics Data System (ADS)

Wang, Yuting; Deutscher, Nicholas M.; Palm, Mathias; Warneke, Thorsten; Notholt, Justus; Baker, Ian; Berry, Joe; Suntharalingam, Parvadha; Jones, Nicholas; Mahieu, Emmanuel; Lejeune, Bernard; Hannigan, James; Conway, Stephanie; Mendonca, Joseph; Strong, Kimberly; Campbell, J. Elliott; Wolf, Adam; Kremser, Stefanie

2016-02-01

Understanding carbon dioxide (CO2) biospheric processes is of great importance because the terrestrial exchange drives the seasonal and interannual variability of CO2 in the atmosphere. Atmospheric inversions based on CO2 concentration measurements alone can only determine net biosphere fluxes, but not differentiate between photosynthesis (uptake) and respiration (production). Carbonyl sulfide (OCS) could provide an important additional constraint: it is also taken up by plants during photosynthesis but not emitted during respiration, and therefore is a potential means to differentiate between these processes. Solar absorption Fourier Transform InfraRed (FTIR) spectrometry allows for the retrievals of the atmospheric concentrations of both CO2 and OCS from measured solar absorption spectra. Here, we investigate co-located and quasi-simultaneous FTIR measurements of OCS and CO2 performed at five selected sites located in the Northern Hemisphere. These measurements are compared to simulations of OCS and CO2 using a chemical transport model (GEOS-Chem). The coupled biospheric fluxes of OCS and CO2 from the simple biosphere model (SiB) are used in the study. The CO2 simulation with SiB fluxes agrees with the measurements well, while the OCS simulation reproduced a weaker drawdown than FTIR measurements at selected sites, and a smaller latitudinal gradient in the Northern Hemisphere during growing season when comparing with HIPPO (HIAPER Pole-to-Pole Observations) data spanning both hemispheres. An offset in the timing of the seasonal cycle minimum between SiB simulation and measurements is also seen. Using OCS as a photosynthesis proxy can help to understand how the biospheric processes are reproduced in models and to further understand the carbon cycle in the real world.

Group dynamics challenges: Insights from Biosphere 2 experiments.

PubMed

Nelson, Mark; Gray, Kathelin; Allen, John P

2015-07-01

Successfully managing group dynamics of small, physically isolated groups is vital for long duration space exploration/habitation and for terrestrial CELSS (Controlled Environmental Life Support System) facilities with human participants. Biosphere 2 had important differences and shares some key commonalities with both Antarctic and space environments. There were a multitude of stress factors during the first two year closure experiment as well as mitigating factors. A helpful tool used at Biosphere 2 was the work of W.R. Bion who identified two competing modalities of behavior in small groups. Task-oriented groups are governed by conscious acceptance of goals, reality-thinking in relation to time and resources, and intelligent management of challenges. The opposing unconscious mode, the "basic-assumption" ("group animal") group, manifests through Dependency/Kill the Leader, Fight/Flight and Pairing. These unconscious dynamics undermine and can defeat the task group's goal. The biospherians experienced some dynamics seen in other isolated teams: factions developing reflecting personal chemistry and disagreements on overall mission procedures. These conflicts were exacerbated by external power struggles which enlisted support of those inside. Nevertheless, the crew evolved a coherent, creative life style to deal with some of the deprivations of isolation. The experience of the first two year closure of Biosphere 2 vividly illustrates both vicissitudes and management of group dynamics. The crew overrode inevitable frictions to creatively manage both operational and research demands and opportunities of the facility, thus staying 'on task' in Bion's group dynamics terminology. The understanding that Biosphere 2 was their life support system may also have helped the mission to succeed. Insights from the Biosphere 2 experience can help space and remote missions cope successfully with the inherent challenges of small, isolated crews. Copyright © 2015 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

The Race for Space: Tracking Land-Cover Transformation in a Socio-ecological Landscape, South Africa

NASA Astrophysics Data System (ADS)

Coetzer, Kaera L.; Erasmus, Barend F. N.; Witkowski, Edward T. F.; Reyers, Belinda

2013-09-01

Biosphere Reserves attempt to align existing biodiversity conservation with sustainable resource use, specifically for improving socio-economic circumstances of resident communities. Typically, the Biosphere Reserve model is applied to an established landscape mosaic of existing land uses; these are often socio-ecological systems where strict environmental protection and community livelihoods are in conflict, and environmental degradation frequently accompanies "use". This raises challenges for successful implementation of the model, as the reality of the existing land-use mosaic undermines the theoretical aspirations of the Biosphere concept. This study focuses on the Kruger to Canyons Biosphere Reserve (K2C), South Africa; a socio-ecological landscape where formal conservation is juxtaposed against extensive impoverished rural communities. We focus on land-cover changes of the existing land-use mosaic (1993-2006), specifically selected land-cover classes identified as important for biodiversity conservation and local-level resource utilization. We discuss the implications of transformation for conservation, sustainable resource-use, and K2C's functioning as a "Biosphere Reserve". Spatially, changes radiated outward from the settlement expanse, with little regard for the theoretical land-use zonation of the Biosphere Reserve. Settlement growth tracked transport routes, transforming cohesive areas of communal-use rangelands. Given the interdependencies between the settlement population and local environmental resources, the Impacted Vegetation class expanded accordingly, fragmenting the Intact Vegetation class, and merging rangelands. This has serious implications for sustainability of communal harvesting areas, and further transformation of intact habitat. The distribution and magnitude of Intact Vegetation losses raise concerns around connectivity and edge effects, with long-term consequences for ecological integrity of remnant habitat, and K2C's existing network of protected areas.

Accuracy and Precision in Measurements of Biomass Oxidative Ratio and Carbon Oxidation State

NASA Astrophysics Data System (ADS)

Gallagher, M. E.; Masiello, C. A.; Randerson, J. T.; Chadwick, O. A.; Robertson, G. P.

2007-12-01

Ecosystem oxidative ratio (OR) is a critical parameter in the apportionment of anthropogenic CO2 between the terrestrial biosphere and ocean carbon reservoirs. OR is the ratio of O2 to CO2 in gas exchange fluxes between the terrestrial biosphere and atmosphere. Ecosystem OR is linearly related to biomass carbon oxidation state (Cox), a fundamental property of the earth system describing the bonding environment of carbon in molecules. Cox can range from -4 to +4 (CH4 to CO2). Variations in both Cox and OR are driven by photosynthesis, respiration, and decomposition. We are developing several techniques to accurately measure variations in ecosystem Cox and OR; these include elemental analysis, bomb calorimetry, and 13C nuclear magnetic resonance spectroscopy. A previous study, comparing the accuracy and precision of elemental analysis versus bomb calorimetry for pure chemicals, showed that elemental analysis-based measurements are more accurate, while calorimetry- based measurements yield more precise data. However, the limited biochemical range of natural samples makes it possible that calorimetry may ultimately prove most accurate, as well as most cost-effective. Here we examine more closely the accuracy of Cox and OR values generated by calorimetry on a large set of natural biomass samples collected from the Kellogg Biological Station-Long Term Ecological Research (KBS-LTER) site in Michigan.

Life on rock. Scaling down biological weathering in a new experimental design at Biosphere-2

NASA Astrophysics Data System (ADS)

Zaharescu, D. G.; Dontsova, K.; Burghelea, C. I.; Chorover, J.; Maier, R.; Perdrial, J. N.

2012-12-01

Biological colonization and weathering of bedrock on Earth is a major driver of landscape and ecosystem development, its effects reaching out into other major systems such climate and geochemical cycles of elements. In order to understand how microbe-plant-mycorrhizae communities interact with bedrock in the first phases of mineral weathering we developed a novel experimental design in the Desert Biome at Biosphere-2, University of Arizona (U.S.A). This presentation will focus on the development of the experimental setup. Briefly, six enclosed modules were designed to hold 288 experimental columns that will accommodate 4 rock types and 6 biological treatments. Each module is developed on 3 levels. A lower volume, able to withstand the weight of both, rock material and the rest of the structure, accommodates the sampling elements. A middle volume, houses the experimental columns in a dark chamber. A clear, upper section forms the habitat exposed to sunlight. This volume is completely sealed form exterior and it allows a complete control of its air and water parameters. All modules are connected in parallel with a double air purification system that delivers a permanent air flow. This setup is expected to provide a model experiment, able to test important processes in the interaction rock-life at grain-to- molecular scale.

Patterns of new versus recycled primary production in the terrestrial biosphere

USDA-ARS?s Scientific Manuscript database

Nitrogen (N) and phosphorus (P) availability regulate plant productivity throughout the terrestrial biosphere, influencing the patterns and magnitude of net primary production (NPP) by land plants both now and into the future. These nutrients enter ecosystems via geologic and atmospheric pathways, a...

A biosphere assessment of high-level radioactive waste disposal in Sweden.

PubMed

Kautsky, Ulrik; Lindborg, Tobias; Valentin, Jack

2015-04-01

Licence applications to build a repository for the disposal of Swedish spent nuclear fuel have been lodged, underpinned by myriad reports and several broader reviews. This paper sketches out the technical and administrative aspects and highlights a recent review of the biosphere effects of a potential release from the repository. A comprehensive database and an understanding of major fluxes and pools of water and organic matter in the landscape let one envisage the future by looking at older parts of the site. Thus, today's biosphere is used as a natural analogue of possible future landscapes. It is concluded that the planned repository can meet the safety criteria and will have no detectable radiological impact on plants and animals. This paper also briefly describes biosphere work undertaken after the review. The multidisciplinary approach used is relevant in a much wider context and may prove beneficial across many environmental contexts. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Influence of indoor environmental factors on mass transfer parameters and concentrations of semi-volatile organic compounds.

PubMed

Wei, Wenjuan; Mandin, Corinne; Ramalho, Olivier

2018-03-01

Semi-volatile organic compounds (SVOCs) in indoor environments can partition among the gas phase, airborne particles, settled dust, and available surfaces. The mass transfer parameters of SVOCs, such as the mass transfer coefficient and the partition coefficient, are influenced by indoor environmental factors. Subsequently, indoor SVOC concentrations and thus occupant exposure can vary depending on environmental factors. In this review, the influence of six environmental factors, i.e., indoor temperature, humidity, ventilation, airborne particle concentration, source loading factor, and reactive chemistry, on the mass transfer parameters and indoor concentrations of SVOCs was analyzed and tentatively quantified. The results show that all mass transfer parameters vary depending on environmental factors. These variations are mostly characterized by empirical equations, particularly for humidity. Theoretical calculations of these parameters based on mass transfer mechanisms are available only for the emission of SVOCs from source surfaces when airborne particles are not present. All mass transfer parameters depend on the temperature. Humidity influences the partition of SVOCs among different phases and is associated with phthalate hydrolysis. Ventilation has a combined effect with the airborne particle concentration on SVOC emission and their mass transfer among different phases. Indoor chemical reactions can produce or eliminate SVOCs slowly. To better model the dynamic SVOC concentration indoors, the present review suggests studying the combined effect of environmental factors in real indoor environments. Moreover, interactions between indoor environmental factors and human activities and their influence on SVOC mass transfer processes should be considered. Copyright © 2017 Elsevier Ltd. All rights reserved.

Land-atmosphere interactions over the continental United States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zeng, Xubin

This paper briefly discusses four suggested modifications for land surface modeling in climate models. The impact of the modifications on climate simulations is analyzed with the Biosphere-Atmosphere Transfer Scheme (BATS) land surface model. It is found that the modifications can improve BATS simulations. In particular, the sensitivity of BATS to the prescribed value of physical root fraction which cannot be observed from satellite remote sensing or field experiments is improved. These modifications significantly reduce the excessive summer land surface temperature over the continental United States simulated by the National Center for Atmospheric Research Community Climate Model (CCM2) coupled with BATS.more » A land-atmosphere interaction mechanism involving energy and water cycles is proposed to explain the results. 9 refs., 1 fig.« less

Towards understanding the variability in biospheric CO2 fluxes: using FTIR spectrometry and a chemical transport model to investigate the sources and sinks of carbonyl sulfide and its link to CO2

NASA Astrophysics Data System (ADS)

Wang, Y.; Deutscher, N. M.; Palm, M.; Warneke, T.; Notholt, J.; Baker, I.; Berry, J.; Suntharalingam, P.; Jones, N.; Mahieu, E.; Lejeune, B.; Campbell, J. E.; Wolf, A.; Kremser, S.

2015-09-01

Understanding carbon dioxide (CO2) biospheric processes is of great importance because the terrestrial exchange drives the seasonal and inter-annual variability of CO2 in the atmosphere. Atmospheric inversions based on CO2 concentration measurements alone can only determine net biosphere fluxes, but not differentiate between photosynthesis (uptake) and respiration (production). Carbonyl sulfide (OCS) could provide an important additional constraint: it is also taken up by plants during photosynthesis but not emitted during respiration, and therefore is a potential mean to differentiate between these processes. Solar absorption Fourier Transform InfraRed (FTIR) spectrometry allows for the retrievals of the atmospheric concentrations of both CO2 and OCS from measured solar absorption spectra. Here, we investigate co-located and quasi-simultaneous FTIR measurements of OCS and CO2 performed at three selected sites located in the Northern Hemisphere. These measurements are compared to simulations of OCS and CO2 using a chemical transport model (GEOS-Chem). The OCS simulations are driven by different land biospheric fluxes to reproduce the seasonality of the measurements. Increasing the plant uptake of Kettle et al. (2002a) by a factor of three resulted in the best comparison with FTIR measurements. However, there are still discrepancies in the latitudinal distribution when comparing with HIPPO (HIAPER Pole-to-Pole Observations) data spanning both hemispheres. The coupled biospheric fluxes of OCS and CO2 from the simple biosphere model (SiB) are used in the study and compared to measurements. The CO2 simulation with SiB fluxes agrees with the measurements well, while the OCS simulation reproduced a weaker drawdown than FTIR measurements at selected sites, and a smaller latitudinal gradient in the Northern Hemisphere during growing season. An offset in the timing of the seasonal cycle minimum between SiB simulation and measurements is also seen. Using OCS as a photosynthesis proxy can help to understand how the biospheric processes are reproduced in models and to further understand the carbon cycle in the real world.

Quantifying the influence of the terrestrial biosphere on glacial-interglacial climate dynamics

NASA Astrophysics Data System (ADS)

Davies-Barnard, Taraka; Ridgwell, Andy; Singarayer, Joy; Valdes, Paul

2017-10-01

The terrestrial biosphere is thought to be a key component in the climatic variability seen in the palaeo-record. It has a direct impact on surface temperature through changes in surface albedo and evapotranspiration (so-called biogeophysical effects) and, in addition, has an important indirect effect through changes in vegetation and soil carbon storage (biogeochemical effects) and hence modulates the concentrations of greenhouse gases in the atmosphere. The biogeochemical and biogeophysical effects generally have opposite signs, meaning that the terrestrial biosphere could potentially have played only a very minor role in the dynamics of the glacial-interglacial cycles of the late Quaternary. Here we use a fully coupled dynamic atmosphere-ocean-vegetation general circulation model (GCM) to generate a set of 62 equilibrium simulations spanning the last 120 kyr. The analysis of these simulations elucidates the relative importance of the biogeophysical versus biogeochemical terrestrial biosphere interactions with climate. We find that the biogeophysical effects of vegetation account for up to an additional -0.91 °C global mean cooling, with regional cooling as large as -5 °C, but with considerable variability across the glacial-interglacial cycle. By comparison, while opposite in sign, our model estimates of the biogeochemical impacts are substantially smaller in magnitude. Offline simulations show a maximum of +0.33 °C warming due to an increase of 25 ppm above our (pre-industrial) baseline atmospheric CO2 mixing ratio. In contrast to shorter (century) timescale projections of future terrestrial biosphere response where direct and indirect responses may at times cancel out, we find that the biogeophysical effects consistently and strongly dominate the biogeochemical effect over the inter-glacial cycle. On average across the period, the terrestrial biosphere has a -0.26 °C effect on temperature, with -0.58 °C at the Last Glacial Maximum. Depending on assumptions made about the destination of terrestrial carbon under ice sheets and where sea level has changed, the average terrestrial biosphere contribution over the last 120 kyr could be as much as -50 °C and -0.83 °C at the Last Glacial Maximum.

Exploring frontiers of the deep biosphere through scientific ocean drilling

NASA Astrophysics Data System (ADS)

Inagaki, F.; D'Hondt, S.; Hinrichs, K. U.

2015-12-01

Since the first deep biosphere-dedicated Ocean Drilling Program (ODP) Leg 201 using the US drill ship JOIDES Resolution in 2002, scientific ocean drilling has offered unique opportunities to expand our knowledge of the nature and extent of the deep biosphere. The latest estimate of the global subseafloor microbial biomass is ~1029cells, accounting for 4 Gt of carbon and ~1% of the Earth's total living biomass. The subseafloor microbial communities are evolutionarily diverse and their metabolic rates are extraordinarily slow. Nevertheless, accumulating activity most likely plays a significant role in elemental cycles over geological time. In 2010, during Integrated Ocean Drilling Program (IODP) Expedition 329, the JOIDES Resolutionexplored the deep biosphere in the open-ocean South Pacific Gyre—the largest oligotrophic province on our planet. During Expedition 329, relatively high concentrations of dissolved oxygen and significantly low biomass of microbial populations were observed in the entire sediment column, indicating that (i) there is no limit to life in open-ocean sediment and (ii) a significant amount of oxygen reaches through the sediment to the upper oceanic crust. This "deep aerobic biosphere" inhabits the sediment throughout up to ~37 percent of the world's oceans. The remaining ~63 percent of the oceans is comprised of higher productivity areas that contain the "deep anaerobic biosphere". In 2012, during IODP Expedition 337, the Japanese drill ship Chikyu explored coal-bearing sediments down to 2,466 meters below the seafloor off the Shimokita Peninsula, Japan. Geochemical and microbiological analyses consistently showed the occurrence of methane-producing communities associated with the coal beds. Cell concentrations in deep sediments were notably lower than those expected from the global regression line, implying that the bottom of the deep biosphere is approached in these beds. Taxonomic composition of the deep coal-bearing communities profoundly differs from those in shallower marine sediments and instead resembles organotrophic communities in forest soils. These findings suggest that the terrigenous microbial ecosystem has been partly retained from the original depositional setting over 20 million years and contributed to deep carbon cycling ever since.

Modelling of the L-band brightness temperatures measured with ELBARA III radiometer on Bubnow wetland

NASA Astrophysics Data System (ADS)

Gluba, Lukasz; Sagan, Joanna; Lukowski, Mateusz; Szlazak, Radoslaw; Usowicz, Boguslaw

2017-04-01

Microwave radiometry has become the main tool for investigating soil moisture (SM) with remote sensing methods. ESA - SMOS (Soil Moisture and Ocean Salinity) satellite operating at L-band provides global distribution of soil moisture. An integral part of SMOS mission are calibration and validation activities involving measurements with ELBARA III which is an L-band microwave passive radiometer. It is done in order to improve soil moisture retrievals - make them more time-effective and accurate. The instrument is located at Bubnow test-site, on the border of cultivated field, fallow, meadow and natural wetland being a part of Polesie National Park (Poland). We obtain both temporal and spatial dependences of brightness temperatures for varied types of land covers with the ELBARA III directed at different azimuths. Soil moisture is retrieved from brightness temperature using L-band Microwave Emission of the Biosphere (L-MEB) model, the same as currently used radiative transfer model for SMOS. Parametrization of L-MEB, as well as input values are still under debate. We discuss the results of SM retrievals basing on data obtained during first year of the radiometer's operation. We analyze temporal dependences of retrieved SM for one-parameter (SM), two-parameter (SM, τ - optical depth) and three-parameter (SM, τ, Hr - roughness parameter) retrievals, as well as spatial dependences for specific dates. Special case of Simplified Roughness Parametrization, combining the roughness parameter and optical depth, is considered. L-MEB processing is supported by the continuous measurements of soil moisture and temperature obtained from nearby agrometeorological station, as well as studies on the soil granulometric composition of the Bubnow test-site area. Furthermore, for better estimation of optical depth, the satellite-derived Normalized Difference Vegetation Index (NDVI) was employed, supported by measured in situ vegetation parameters (such as Leaf Area Index and Vegetation Water Content) obtained during the field campaigns. The values of NDVI around ELBARA III radiometer are provided by Sentinel-2 satellite with approximately 10 m spatial resolution and average 10 days of time interval within studied period of time. The work was partially funded under two ESA projects: 1) "ELBARA_PD (Penetration Depth)" No. 4000107897/13/NL/KML, funded by the Government of Poland through an ESA-PECS contract (Plan for European Cooperating States). 2) "Technical Support for the fabrication and deployment of the radiometer ELBARA-III in Bubnow, Poland" No. 4000113360/15/NL/FF/gp.

Access 1996: A directory of permanent plots which monitor flora, fauna, climate, hydrology, soil, geology, and the effects of anthropogenic changes at 132 biosphere reserves in 27 countries

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-07-01

This directory summarizes information about environmental data collected in permanent monitoring and research plots in 132 biosphere reserves in Canada, the United States, and 25 European countries. The text of the directory is organized alphabetically by country and, within each country, alphabetically according to the name of the biosphere reserve. Tabular summaries of information on permanent plots are provided. The summaries are organized topically . A general summary of basic information on permanent plots is followed by more detailed information on permanent plots dedicated primarily to monitroing and research on particular topics.

From the Big Bang to sustainable societies.

PubMed

Eriksson, K E; Robèrt, K H

1991-01-01

A series of events in the history of cosmos has created the prerequisites for life on Earth. With respect to matter, the earth is a closed system. However, it receives light from the sun and emits infrared radiation into space. The difference in thermodynamic potential between these two flows has provided the physical conditions for self-organization. The transformation of lifeless matter into modern life forms, with their high degree of order and complexity, has occurred in the context of the earth's natural cycles, including the water cycle and the biochemical cycles between plants and animals. Primary production units, the cells of green plants, can use the thermodynamic potential of the energy balance in a very direct way, i.e. in photosynthesis. Plant cells are unique in their ability to synthesize more structure than is broken down elsewhere in the biosphere. The perpetuation of this process requires the recycling of wastes. However, modern industrial societies are obsessed with the supply side, ignoring the principle of matter's conservation and neglecting to plan for the entire material flow. As a result there has been an accumulation of both visible and invisible garbage (pollution), which disturbs the biosphere and reduces stocks of natural resources. Furthermore, due to complexity and delay mechanisms, we usually cannot predict time parameters for the resulting socio-economic consequences or the development of disease. To continue along this path of folly is not compatible with the maintenance of wealth, nor with the health of humans or the biosphere. Rather than address the millions of environmental problems one at a time, we need to approach them at the systemic level. It is essential to convert to human life-styles and forms of societal organization that are based on cyclic processes compatible with the earth's natural cycles. The challenge to the developed countries is not only to decrease their own emissions of pollutants but to develop the cyclic technology and life styles needed by the entire human community.

10 CFR 63.305 - Required characteristics of the reference biosphere.

Code of Federal Regulations, 2013 CFR

2013-01-01

... the region surrounding the Yucca Mountain site. (b) DOE should not project changes in society, the biosphere (other than climate), human biology, or increases or decreases of human knowledge or technology... vary factors related to the geology, hydrology, and climate based upon cautious, but reasonable...

10 CFR 63.305 - Required characteristics of the reference biosphere.

Code of Federal Regulations, 2014 CFR

2014-01-01

... the region surrounding the Yucca Mountain site. (b) DOE should not project changes in society, the biosphere (other than climate), human biology, or increases or decreases of human knowledge or technology... vary factors related to the geology, hydrology, and climate based upon cautious, but reasonable...

10 CFR 63.305 - Required characteristics of the reference biosphere.

Code of Federal Regulations, 2012 CFR

2012-01-01

... the region surrounding the Yucca Mountain site. (b) DOE should not project changes in society, the biosphere (other than climate), human biology, or increases or decreases of human knowledge or technology... vary factors related to the geology, hydrology, and climate based upon cautious, but reasonable...

10 CFR 63.305 - Required characteristics of the reference biosphere.

Code of Federal Regulations, 2010 CFR

2010-01-01

... the region surrounding the Yucca Mountain site. (b) DOE should not project changes in society, the biosphere (other than climate), human biology, or increases or decreases of human knowledge or technology... vary factors related to the geology, hydrology, and climate based upon cautious, but reasonable...

Reaching for Excellence.

ERIC Educational Resources Information Center

Wright, Emmett L.; Perna, Jack A.

1992-01-01

Presents the four program goals for biology set forth in the National Science Teacher Association's "A Focus on Excellence: Biology Revisited" to (1) address biosphere, human society, and individual needs; (2) encourage students to experience, understand, and appreciate of natural systems; (3) apply the basic concept of the biosphere; and (4)…

The World Campaign for the Biosphere.

ERIC Educational Resources Information Center

Barman, Charles R.

1984-01-01

Lists and discusses goals of The World Campaign for the Biosphere and strategies designed to achieve these goals. Also lists eight suggestions for science teachers to help incorporate the goals into school curricula and programs. These include organizing assemblies which present information about environmental problems and presenting environmental…

Viral infections as controlling factors for the deep biosphere? (Invited)

NASA Astrophysics Data System (ADS)

Engelen, B.; Engelhardt, T.; Sahlberg, M.; Cypionka, H.

2009-12-01

The marine deep biosphere represents the largest biotope on Earth. Throughout the last years, we have obtained interesting insights into its microbial community composition. However, one component that was completely overlooked so far is the viral inventory of deep-subsurface sediments. While viral infections were identified to have a major impact on the benthic microflora of deep-sea surface sediments (Danavaro et al. 2008), no studies were performed on deep-biosphere samples, so far. As grazers probably play only a minor role in anoxic and highly compressed deep sediments, viruses might be the main “predators” for indigenous microorganisms. Furthermore, the release of cell components, called “the viral shunt”, could have a major impact on the deep biosphere in providing labile organic compounds to non-infected microorganisms in these generally nutrient depleted sediments. However, direct counting of viruses in sediments is highly challenging due to the small size of viruses and the high background of small particles. Even molecular surveys using “universal” PCR primers that target phage-specific genes fail due to the vast phage diversity. One solution for this problem is the lysogenic viral life cycle as many bacteriophages integrate their DNA into the host genome. It is estimated that up to 70% of cultivated bacteria contain prophages within their genome. Therefore, culture collections (Batzke et al. 2007) represent an archive of the viral composition within the respective habitat. These prophages can be induced to become free phage particles in stimulation experiments in which the host cells are set under certain stress situations such as a treatment with UV exposure or DNA-damaging antibiotics. The study of the viral component within the deep biosphere offers to answer the following questions: To which extent are deep-biosphere populations controlled by viral infections? What is the inter- and intra-specific diversity and the host-specific viral biogeography? Can viral infections tell us something about the physiological state of indigenous microorganisms? Finally, we will obtain estimates for the viral shunt as an important factor for sustaining the deep biosphere. References: Batzke A, Engelen B, Sass H, Cypionka H (2007) Phylogenetic and physiological diversity of cultured deep-biosphere bacteria from Equatorial Pacific Ocean and Peru Margin sediments. Geomicrobiology J 24:261-273 Danovaro R, Dell'Anno A, Corinaldesi C, Magagnini M, Noble R, Tamburini C, Weinbauer M (2008) Major viral impact on the functioning of benthic deep-sea ecosystems. Nature 454: 1084-U1027.

Self-organization of the earth's biosphere-geochemical or geophysiological?

NASA Technical Reports Server (NTRS)

Schwartzman, David W.; Shore, Steven N.; Volk, Tyler; Mcmenamin, Mark

1994-01-01

We explore the implications of indicating the biosphere's self-organization by the trend over time of the net entropic flow from the Earth's surface, the actual physical boundary of virtually all biotic mass. This flow, derived from the radiative surface entropy budget, is approximately inversely related to the surface temperature when the solar incident flux remains constant. In the geophysiological ('gaian') interpretation, biospheric self-organization has increased with the progressive colonization of the continents and evolutionary developments in the land biota, as a result of surface cooling arising from biotic enhancement of weathering. The key site for this self-organization is at the interface between land and atmosphere, the soil, where carbon is sequestered by its reaction (as carbonic and organic acids) with calcium magnesium silicates. Along with disequilibrium (steady-state) levels of carbon dioxide in the atmosphere, the occurrence of differentiated soil is the critical material evidence for biospheric self-organization, whether it be geophysiological or geochemical (ie., purely result of inorganic reactions). The computed equilibrium levels of carbon dioxide and corresponding equilibrium temperatures in the past are dramatically different from the steady-state levels. With future solar luminosity increase, the biospheric capacity for climatic regulation will decrease, leading to the ending of self-organization some two billion years from now. The Earth's surface will then approach chemical equilibrium with respect to the carbonate-silicate cycle.

Inhabitants' environmental perceptions in the city of Rome within the framework for urban biosphere reserves of the UNESCO programme on man and biosphere.

PubMed

Bonnes, Mirilia; Carrus, Giuseppe; Bonaiuto, Marino; Fornara, Ferdinando; Passafaro, Paola

2004-06-01

The article presents the main tenets of the UNESCO Programme on Man and Biosphere (MAB), launched by the United Nations at the beginning of the 1970s. The program aimed at supporting applied research and scientific knowledge for managing natural resources in a rational and sustainable way. The implication of the full ecological perspective, typical of the MAB, for promoting multidisciplinary and integrated approaches in the study of environmental issues is briefly outlined. In particular, we point out the role of the MAB, through the biosphere reserve concept, in supporting the collaboration between natural-biological and social-behavioral sciences when dealing with biodiversity conservation problems and with urban ecosystems. Then, the specific UNESCO-MAB Project on the city of Rome, launched at the end of the 1980s, is briefly presented, together with the recent project of the Department of the Environment of the Rome Municipality to propose Rome's urban and periurban green areas as a new UNESCO-MAB Biosphere Reserve. The results of the main research activities conducted therein are summarized. In particular, the specific research lines of the environmental psychology research group, involved in the MAB-Rome Project for approximately two decades, are presented. These research lines dealt with various aspects of residents' environmental perceptions and behaviors in the city of Rome. The practical implications of these results are also briefly discussed.

Impact of the 2008 Wenchuan earthquake on river organic carbon provenance: Insight from biomarkers

NASA Astrophysics Data System (ADS)

Wang, Jin; Feng, Xiaojuan; Hilton, Robert; Jin, Zhangdong; Ma, Tian; Zhang, Fei; Li, Gen; Densmore, Alexander; West, A. Joshua

2017-04-01

Large earthquakes can trigger widespread landslides in active mountain belts, which can mobilize biospheric organic carbon (OC) from the soil and vegetation. Rivers can erode and export biospheric particulate organic carbon (POC), which is an export of ecosystem productivity and may result in a CO2 sink if buried in sedimentary deposits. Our previous work showed that the 2008 Mw 7.9 Wenchuan earthquake increased the discharge of biospheric OC by rivers, due to the increased supply by earthquake triggered landslides (Wang et al., 2016). However, while the OC derived from sedimentary rocks could be accounted for, the source of biospheric OC in rivers before and after the earthquake remains poorly constrained. Here we use suspended sediment samples collected from the Zagunao River before and after the Wenchuan earthquake and measured the specific compounds of OC, including fatty acids, lignin phenols and glycerol dialkyl glycerol tetraether (GDGT) lipids. In combination with the analysis of bulk elemental concentration (C and N) and carbon isotopic ratio, the new data shows differential export patterns for OC components derived from varied terrestrial sources. A high frequency sampling enabled us to explore how the biospheric OC source changes following the earthquake, helping to better understand the link between active tectonics and the carbon cycle. Our results are also important in revealing how sedimentary biomarker records may record past earthquakes.

The Anthropocene: a conspicuous stratigraphical signal of anthropogenic changes in production and consumption across the biosphere

NASA Astrophysics Data System (ADS)

Williams, Mark; Zalasiewicz, Jan; Waters, Colin N.; Edgeworth, Matt; Bennett, Carys; Barnosky, Anthony D.; Ellis, Erle C.; Ellis, Michael A.; Cearreta, Alejandro; Haff, Peter K.; Ivar do Sul, Juliana A.; Leinfelder, Reinhold; McNeill, John R.; Odada, Eric; Oreskes, Naomi; Revkin, Andrew; Richter, Daniel deB; Steffen, Will; Summerhayes, Colin; Syvitski, James P.; Vidas, Davor; Wagreich, Michael; Wing, Scott L.; Wolfe, Alexander P.; Zhisheng, An

2016-03-01

Biospheric relationships between production and consumption of biomass have been resilient to changes in the Earth system over billions of years. This relationship has increased in its complexity, from localized ecosystems predicated on anaerobic microbial production and consumption to a global biosphere founded on primary production from oxygenic photoautotrophs, through the evolution of Eukarya, metazoans, and the complexly networked ecosystems of microbes, animals, fungi, and plants that characterize the Phanerozoic Eon (the last ˜541 million years of Earth history). At present, one species, Homo sapiens, is refashioning this relationship between consumption and production in the biosphere with unknown consequences. This has left a distinctive stratigraphy of the production and consumption of biomass, of natural resources, and of produced goods. This can be traced through stone tool technologies and geochemical signals, later unfolding into a diachronous signal of technofossils and human bioturbation across the planet, leading to stratigraphically almost isochronous signals developing by the mid-20th century. These latter signals may provide an invaluable resource for informing and constraining a formal Anthropocene chronostratigraphy, but are perhaps yet more important as tracers of a biosphere state that is characterized by a geologically unprecedented pattern of global energy flow that is now pervasively influenced and mediated by humans, and which is necessary for maintaining the complexity of modern human societies.

On the uncertainty of phenological responses to climate change, and implications for a terrestrial biosphere model

NASA Astrophysics Data System (ADS)

Migliavacca, M.; Sonnentag, O.; Keenan, T. F.; Cescatti, A.; O'Keefe, J.; Richardson, A. D.

2012-06-01

Phenology, the timing of recurring life cycle events, controls numerous land surface feedbacks to the climate system through the regulation of exchanges of carbon, water and energy between the biosphere and atmosphere. Terrestrial biosphere models, however, are known to have systematic errors in the simulation of spring phenology, which potentially could propagate to uncertainty in modeled responses to future climate change. Here, we used the Harvard Forest phenology record to investigate and characterize sources of uncertainty in predicting phenology, and the subsequent impacts on model forecasts of carbon and water cycling. Using a model-data fusion approach, we combined information from 20 yr of phenological observations of 11 North American woody species, with 12 leaf bud-burst models that varied in complexity. Akaike's Information Criterion indicated support for spring warming models with photoperiod limitations and, to a lesser extent, models that included chilling requirements. We assessed three different sources of uncertainty in phenological forecasts: parameter uncertainty, model uncertainty, and driver uncertainty. The latter was characterized running the models to 2099 using 2 different IPCC climate scenarios (A1fi vs. B1, i.e. high CO2 emissions vs. low CO2 emissions scenario). Parameter uncertainty was the smallest (average 95% Confidence Interval - CI: 2.4 days century-1 for scenario B1 and 4.5 days century-1 for A1fi), whereas driver uncertainty was the largest (up to 8.4 days century-1 in the simulated trends). The uncertainty related to model structure is also large and the predicted bud-burst trends as well as the shape of the smoothed projections varied among models (±7.7 days century-1 for A1fi, ±3.6 days century-1 for B1). The forecast sensitivity of bud-burst to temperature (i.e. days bud-burst advanced per degree of warming) varied between 2.2 days °C-1 and 5.2 days °C-1 depending on model structure. We quantified the impact of uncertainties in bud-burst forecasts on simulated photosynthetic CO2 uptake and evapotranspiration (ET) using a process-based terrestrial biosphere model. Uncertainty in phenology model structure led to uncertainty in the description of forest seasonality, which accumulated to uncertainty in annual model estimates of gross primary productivity (GPP) and ET of 9.6% and 2.9%, respectively. A sensitivity analysis shows that a variation of ±10 days in bud-burst dates led to a variation of ±5.0% for annual GPP and about ±2.0% for ET. For phenology models, differences among future climate scenarios (i.e. driver) represent the largest source of uncertainty, followed by uncertainties related to model structure, and finally, related to model parameterization. The uncertainties we have quantified will affect the description of the seasonality of ecosystem processes and in particular the simulation of carbon uptake by forest ecosystems, with a larger impact of uncertainties related to phenology model structure, followed by uncertainties related to phenological model parameterization.

Mars Exobiology: The Principles Behind The Plan For Exploration

NASA Technical Reports Server (NTRS)

DesMarais, D. J.; DeVincenzi, Donald L.; Carr, M. H.; Clark, B. C.; Farmer, J. D.; Hayes, J. M.; Holland, H.; Kerridge, J. F.; Klein, H. P.; McDonald, G. D.

1995-01-01

The search for evidence of life on Mars is a highly interdisciplinary enterprise which extends beyond the traditional life sciences. Mars conceivably had a pervasive ancient biosphere which may have persisted even to the present, but only in subsurface environments. Understanding the history of Mars' global environment, including its inventory of volatile elements, is a crucial part of the search strategy. Those deposits (minerals, sediments, etc.) which could have and retained a record of earlier biological activity must be identified and examined. While the importance of. seeking another biosphere has not diminished during the years since the Viking mission, the strategy for Mars exploration certainly has been modified by later discoveries. The Viking mission itself demonstrated that the present day surface environment of Mars is hostile to life as we know it. Thus, to search effectively for life on Mars, be it extant or extinct, we now must greatly improve our understanding of Mars the planet. Such an understanding will help us broaden our search beyond the Viking lander sites, both back in time to earlier epochs and elsewhere to other sites and beneath the surface. Exobiology involves much more than simply a search for extant life beyond Earth. It addresses the prospect of long-extinct biospheres and also the chemistry, organic and otherwise, which either led to life or which occurred on rocky planets that remained lifeless. Even a Mars without a biosphere would reveal much about life. How better to understand the origin and impact of a biosphere than to compare Earth with another similar but lifeless planet? Still, several relatively recent discoveries offer encouragement that a Martian biosphere indeed might have existed. The ancient Martian surface was extensively sculptured by volcanism and the activity of liquid water. Such observations invoke impressions of an ancient martian atmosphere and environment that resembled ancient Earth more than present-day Mars. Since Viking, we have learned that our own biosphere began prior to 3.5 billion years ago, during an early period when our solar system apparently was sustaining clement conditions on at least two of its planets. Also, we have found that microorganisms can survive, even flourish, in environments more extreme in temperature and water availability than had been previously recognized. The common ancestor of life on Earth probably was adapted to elevated temperatures, raising the possibility that hydrothermal systems played a central role in sustaining our early biosphere. If a biosphere ever arose on Mars, at least some of its constituents probably dwelled in the subsurface. Even today, conditions on Mars and Earth become more similar with increasing depth beneath their surfaces. For example, under the martian permafrost, the geothermal gradient very likely maintains liquid water in environments which resemble aquifers on Earth. Indigenous bacteria have recently been recovered from deep aquifers on Earth. Liquid groundwater very likely persisted throughout Mars' history. Thus, martian biota, if they ever existed, indeed might have survived in subsurface environments.

Aircraft and satellite thermographic systems for wildfire mapping and assessment

NASA Technical Reports Server (NTRS)

Brass, J. A.; Arvesen, J. C.; Ambrosia, V. G.; Riggan, P. J.; Myers, J. S.

1987-01-01

Two complementary sensors, the DAEDALUS DEI-1260 Multispectral Scanner aboard the NASA U-2 aircraft and the Advanced Very High Resolution Radiometer aboard National Oceanographic and Atmospheric Administration orbiting satellites were tested for their applicability in monitoring and predicting parameters such as fire location, temperature and rate of spread, soil heating and cooling rates, and plume characteristics and dimensions. In addition, the satellite system was tested for its ability to extend the relationships found between fire characteristics and biospheric consequences to regional and global scales. An overall system design is presented, and special requirements are documented for the application of this system for fire research and management.

10 CFR 63.305 - Required characteristics of the reference biosphere.

Code of Federal Regulations, 2011 CFR

2011-01-01

....305 Section 63.305 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DISPOSAL OF HIGH-LEVEL RADIOACTIVE... biosphere (other than climate), human biology, or increases or decreases of human knowledge or technology... factors remain constant as they are at the time of submission of the license application. (c) DOE must...

Bright Coherent Optical Waveforms from the Infrared to the Vacuum Ultraviolet for Manipulation and Detection of Molecules

DTIC Science & Technology

2012-12-13

Margaret Murnane. Invited talk, ITAMP Winter School on Atomic, Molecular and Optical Physics ( Biosphere 2, AZ, January 2012). McElvain Lecture...Molecular and Optical Physics ( Biosphere 2, AZ, January 2012). McElvain Lecture, University of Wisconsin Chemistry Department, February 2012. Seminar

Geoscience parameter data base handbook: granites and basalts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1979-12-01

The Department of Energy has the responsibility for selecting and constructing Federal repositories for radioactive waste. The Nuclear Regulatory Commission must license such repositories prior to construction. The basic requirement in the geologic disposal of radioactive waste is stated as: placement in a geologic host whereby the radioactive waste is not in mechanical, thermal or chemical equilibrium with the object of preventing physical or chemical migration of radionuclides into the biosphere or hydrosphere in hazardous concentration (USGS, 1977). The object of this report is to document the known geologic parameters of large granite and basalt occurrences in the coterminous Unitedmore » States, for future evaluation in the selection and licensing of radioactive waste repositories. The description of the characteristics of certain potential igneous hosts has been limited to existing data pertaining to the general geologic character, geomechanics, and hydrology of identified occurrences. A description of the geochemistry is the subject of a separate report.« less

VIS and NIR land surface albedo sensitivity of the Ent Terrestrial Biosphere Model to forcing leaf area index

NASA Astrophysics Data System (ADS)

Montes, C.; Kiang, N. Y.; Ni-Meister, W.; Yang, W.; Schaaf, C.; Aleinov, I. D.; Jonas, J.; Zhao, F. A.; Yao, T.; Wang, Z.; Sun, Q.; Carrer, D.

2016-12-01

Land surface albedo is a major controlling factor in vegetation-atmosphere transfers, modifying the components of the energy budget, the ecosystem productivity and patterns of regional and global climate. General Circulation Models (GCMs) are coupled to Dynamic Global Vegetation Models (DGVMs) to solve vegetation albedo by using simple schemes prescribing albedo based on vegetation classification, and approximations of canopy radiation transport for multiple plant functional types (PFTs). In this work, we aim at evaluating the sensitivity of the NASA Ent Terrestrial Biosphere Model (TBM), a demographic DGVM coupled to the NASA Goddard Institute for Space Studies (GISS) GCM, in estimating VIS and NIR surface albedo by using variable forcing leaf area index (LAI). The Ent TBM utilizes a new Global Vegetation Structure Dataset (GVSD) to account for geographically varying vegetation tree heights and densities, as boundary conditions to the gap-probability based Analytical Clumped Two-Stream (ACTS) canopy radiative transfer scheme (Ni-Meister et al., 2010). Land surface and vegetation characteristics for the Ent GVSD are obtained from a number of earth observation platforms and algorithms, including the Moderate Resolution Imaging Spectroradiometer (MODIS) land cover and plant functional types (PFTs) (Friedl et al., 2010), soil albedo derived from MODIS (Carrer et al., 2014), and vegetation height from the Geoscience Laser Altimeter System (GLAS) on board ICESat (Ice, Cloud, and land Elevation Satellite) (Simard et al., 2011; Tang et al., 2014). Three LAI products are used as input to ACTS/Ent TBM: MODIS MOD15A2H product (Yang et al., 2006), Beijing Normal University LAI (Yuan et al., 2011), and Global Data Sets of Vegetation (LAI3g) (Zhu et al. 2013). The sensitivity of the Ent TBM VIS and NIR albedo to the three LAI products is assessed, compared against the previous GISS GCM vegetation classification and prescribed Lambertian albedoes (Matthews, 1984), and against MODIS snow-free black-sky and white-sky albedo estimates. In addition, we test the sensitivity of the Ent/ACTS albedo to different sets of leaf spectral albedos derived from the literature.

Improving precipitation simulation from updated surface characteristics in South America

NASA Astrophysics Data System (ADS)

Pereira, Gabriel; Silva, Maria Elisa Siqueira; Moraes, Elisabete Caria; Chiquetto, Júlio Barboza; da Silva Cardozo, Francielle

2017-07-01

Land use and land cover maps and their physical-chemical and biological properties are important variables in the numerical modeling of Earth systems. In this context, the main objective of this study is to analyze the improvements resulting from the land use and land cover map update in numerical simulations performed using the Regional Climate Model system version 4 (RegCM4), as well as the seasonal variations of physical parameters used by the Biosphere Atmosphere Transfer Scheme (BATS). In general, the update of the South America 2007 land use and land cover map, used by the BATS, improved the simulation of precipitation by 10 %, increasing the mean temporal correlation coefficient, compared to observed data, from 0.84 to 0.92 (significant at p < 0.05, Student's t test). Correspondingly, the simulations performed with adjustments in maximum fractional vegetation cover, in visible and shortwave infrared reflectance, and in the leaf area index, showed a good agreement for maximum and minimum temperature, with values closer to observed data. The changes in physical parameters and land use updating in BATS/RegCM4 reduced overestimation of simulated precipitation from 19 to 7 % (significant at p < 0.05, Student's t test). Regarding evapotranspiration and precipitation, the most significant differences due to land use updating were located (1) in the Amazon deforestation arc; (2) around the Brazil-Bolivia border (in the Brazilian Pantanal wetlands); (3) in the Northeast region of Brazil; (4) in northwestern Paraguay; and (5) in the River Plate Basin, in Argentina. Moreover, the main precipitation differences between sensitivity and control experiments occurred during the rainy months in central-north South America (October to March). These were associated with a displacement in the South Atlantic convergence zone (SACZ) positioning, presenting a spatial pattern of alternated areas with higher and lower precipitation rates. These important differences occur due to the replacement of tropical rainforest for pasture and agriculture and the replacement of agricultural areas for pasture, scrubland, and deciduous forest.

Background monitoring and its role in global estimation and forecast of the state of the biosphere.

PubMed

Izrael, Y A

1982-12-01

(1) Scientific grounds and the concept of monitoring as the system for observations, assessment and prediction of man-induced changes in the state of natural environment, the program and aims of the background monitoring were developed by the author in 1972-1980. These questions were discussed in detail at the International Symposium on Global Integrated Monitoring (Riga, U.S.S.R., December, 1978). It should be stressed that along with significant anthropogenic loading on large cities and industrial areas, natural ecosystems covering most of the Earth's territory are also exposed to quite extended, though insignificant anthropogenic effects. This paper proposes to consider the ways of the background information use for the biosphere state assessment and prediction. (2) Classification of objects for monitoring from the point of view of the consequences of the man-made impact, pollution in the first hand, is as follows: - population (public health); - ecosystem elements employed by man whose production is used by population (soil, water bodies, forest, etc.); - biotic elements of ecosystems (without the immediate consumed production); - abiotic constituents of natural ecosystems, considerable components of the biosphere, climatic system. (3) Historically, monitoring in all countries involves the first two spheres. The background monitoring also extends on the next two spheres. It should differentially take into account physical, chemical and biological factors of impacts. Indentification of biological effects is most complex and vital. Human impact at the background level proceeds indirectly through a general (global or regional) deterioration of the state of the biosphere. (4) Gradually the background monitoring is being practiced on a larger and larger scale. It is shown that the long-range atmospheric transport of pollutants in various regions leads to a gradual general increase of all the natural media pollution and to perceptible biological effects (soil and water acidification and resulting disturbances in the composition of soil and water organisms). The levels of the background impact differ. Thus, the background concentrations of a number of anthropogenic pollutants in Central Europe is 10-20 times higher than in Central Asia. (5) The area of priority in the background monitoring of the biosphere pollution has become evident: compounds of sulphur, mercury and their derivatives, organochloride pesticides, some radioactive substances (e.g., krypton-85 in the atmosphere). (6) The World Ocean is practically all contaminated on a global scale. Biological effects of the World Ocean pollution cause special concern. Particularly important consequences, including climate impact, may be caused by disturbances in energy and matter transfer between environmental media (water-air, water-bottom, etc.). The priority of the impact factors can be allocated here as well: oil products, metals, organochloride compounds, polycyclic aromatic hydrocarbons. (7) One of the most effective possibilities of environmental quality control is standardization which consists in elaboration of permissible ecological loadings upon ecosystems and natural media. The approach to ecological standardization differs from that of hygienic control in principle. The objective of ecological standardization is to ensure the integrity of the given ecosystem and natural environment on the whole. (8) Ecological standardization in its turn requires knowledge related to the damage from this or another impact because in such a case there is a possibility to compare ecological standards for the same ecosystem in the case when impacts are of different origin (e.g., different pollutants).

A global biogeocenotical biosphere simulation

NASA Technical Reports Server (NTRS)

Moiseyev, N. N.

1980-01-01

This model of the D. Forrester type, constructed in differential equations, predicts the food and mineral supply for the factors biosphere population, depending on two socio-economic factors, until about the year 2500. If contemporary rates of natural resources utilization are maintained and there is no management of the environment, food resources will begin to limit human population growth after 2200, and mineral resources will after 2300. A decrease in the biosphere pollution, increase in effective agricultural production, and discovery of new energy sources may forestall or completely avert the onset of a crisis situation. Conservation measures, according to the model, are to a considerable extent realizable only if carried out simultaneously in both areas.

Biospheres and solar system exploration

NASA Technical Reports Server (NTRS)

Paine, Thomas O.

1990-01-01

The implications of biosphere technology is briefly examined. The exploration status and prospects of each world in the solar system is briefly reviewed, including the asteroid belt, the moon, and comets. Five program elements are listed as particularly critical for future interplanetary operations during the coming extraterrestrial century. They include the following: (1) a highway to Space (earth orbits); (2) Orbital Spaceports to support spacecraft assembly, storage, repair, maintenance, refueling, launch, and recovery; (3) a Bridge Between Worlds to transport cargo and crews to the moon and beyond to Mars; (4) Prospecting and Resource Utilization Systems to map and characterize the resources of planets, moons, and asteroids; and (5) Closed Ecology Biospheres. The progress in these five field is reviewed.

Modelling soil and soil to plant transfer processes of radionuclides and toxic chemicals at long time scales for performance assessment of Radwaste disposal

NASA Astrophysics Data System (ADS)

Albrecht, Achim; Miquel, Stephan

2015-04-01

Performance assessments for surface nuclear waste disposal facilities require simulation of transfer processes from the waste canisters to a reference group living near-by. Such simulations need to be extended over several hundred to hundred thousand years, depending on waste type, restraining possibilities to represent short term system complexity and variability. Related modelling can be simplified as long as processes are represented conservatively with assessment endpoints estimated larger compared to more realistic modelling approaches. The indicators are doses for radionuclides (RN) and risk factors for toxic chemicals (TC, i.e. heavy metals, nitrate). We discuss a new simulation tool (SCM-Andra-multilayer-model, SAMM) that, among others, allows to model situations where RN/TC move through a soil profile characterised by temporal undersaturation and root growth (soil-plant subsystem of the biosphere model compared to the adjacent saturated geosphere). SAMM describes all relevant transfer and reaction processes (advection, diffusion, root transport, radioactive decay, chemical reactions incl. sorption - desorption) using well known differential equations solved numerically within MATLAB with scenario description and parameterisation defined in Excel sheets. With this conservative approach in mind, we apply global parameters for which the solid-solution (Kd) or soil-to-plant (TF) distribution coefficients are the most relevant. Empirical data are available for homogeneous situations, such as one compartment pot experiments, but rare for entire soil profiles. Similarly soil hydrology, in particular upward and downward advective fluxes are modelled using an empirical approach solely based on key soil hydrological parameters (precipitation, evapotranspiration, irrigation, water table level) and the soil porosity. Variability of soil hydrology in space and time, likely to change drastically even on hourly bases (i.e. intense precipitation event) or within a single column (i.e. preferential flow and capillary rise) is nonetheless represented by annual averages. Changing water saturation and associated variability in redox conditions, RN/TC speciation and mobility, represents an example, where the simulation abilities with SAMM are beyond our capacity of in situ observation and measurement, restricting of course our efforts of validation. The latter is thus limited to simpler cases with parameter values stable within the soil column or throughout time. The study of more complex situations is possible with the SAMM simulation tool. For illustration, we give at least two examples, one for a RN and one for a TC; we evaluate the species initially present as well as the daughter RN and the product of reactivity of the TC. Focus is given to situations where RN/TC are present at the base of a soil column; simulation end points are concentrations at the soil surface and for specified agricultural plant species. Dose and risk calculations based on these data are carried out in classical food chain assessment tools. These illustrations are for generic sites and situations for which at least a minor component of upward advective movement is considered, keeping in mind the conservative approach mentioned above.

Skin friction and heat transfer correlations for high-speed low-density flow past a flat plate

NASA Technical Reports Server (NTRS)

Woronowicz, Michael S.; Baganoff, Donald

1991-01-01

The independent and dependent variables associated with drag and heat transfer to a flat plate at zero incidence in high-speed, rarefied flow are analyzed anew to reflect the importance of kinetic effects occurring near the plate surface on energy and momentum transfer, rather than following arguments normally used to describe continuum, higher density flowfields. A new parameter, the wall Knudsen number Knx,w, based on an estimate of the mean free path length of molecules having just interacted with the surface of the plate, is introduced and used to correlate published drag and heat transfer data. The new parameter is shown to provide better correlation than either the viscous interaction parameter X or the widely-used slip parameter Voo for drag and heat transfer data over a wide range of Mach numbers, Reynolds numbers, and plate-to-freestream stagnation temperature ratios.

Mars Analog Rio Tinto Experiment (MARTE): 2003 Drilling Campaign to Search for a Subsurface Biosphere at Rio Tinto Spain

NASA Astrophysics Data System (ADS)

Stoker, C.; Dunagan, S.; Stevens, T.; Amils, R.; Gómez-Elvira, J.; Fernández, D.; Hall, J.; Lynch, K.; Cannon, H.; Zavaleta, J.; Glass, B.; Lemke, L.

2004-03-01

The results of an drilling experiment to search for a subsurface biosphere in a pyritic mineral deposit at Rio Tinto, Spain, are described. The experiment provides ground truth for a simulation of a Mars drilling mission to search for subsurface life.

76 FR 23649 - Endangered and Threatened Wildlife and Plants; 12-Month Finding on a Petition and Proposed Rule...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-27

... field research), the potential global population of free-ranging Morelet's crocodiles in 2004 was... will include monitoring and harvest of Morelet's crocodiles and hybrids for scientific research (CITES... Biosphere Reserve, Laguna de T[eacute]rminos Biosphere Reserve, Hampolol Wildlife Conservation and Research...

Putting the Deep Biosphere and Gas Hydrates on the Map

ERIC Educational Resources Information Center

Sikorski, Janelle J.; Briggs, Brandon R.

2016-01-01

Microbial processes in the deep biosphere affect marine sediments, such as the formation of gas hydrate deposits. Gas hydrate deposits offer a large source of natural gas with the potential to augment energy reserves and affect climate and seafloor stability. Despite the significant interdependence between life and geology in the ocean, coverage…

The Large-Scale Biosphere-Atmosphere Experiment in Amazonia: Analyzing Regional Land Use Change Effects.

Treesearch

Michael Keller; Maria Assunção Silva-Dias; Daniel C. Nepstad; Meinrat O. Andreae

2004-01-01

The Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) is a multi-disciplinary, multinational scientific project led by Brazil. LBA researchers seek to understand Amazonia in its global context especially with regard to regional and global climate. Current development activities in Amazonia including deforestation, logging, cattle ranching, and agriculture...

The potential impacts of nutrient and CO2 variations on ecosystem oxidative ratio

USDA-ARS?s Scientific Manuscript database

A fraction of fossil fuel carbon dioxide (CO2) emissions are being taken up by the terrestrial biosphere and the oceans. One particularly effective way of determining the sizes of these terrestrial biosphere and ocean carbon sinks is based on the measurements of changes in atmospheric oxygen (O2) a...

International Co-ordinating Council of the Programme on Man and the Biosphere (MAB). Final Report.

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Paris (France).

Man and the Biosphere Program is an interdisciplinary program of research which emphasizes an ecological approach to the study of interrelationships between man and the environment. It is concerned with subjects of global or major regional significance which require international cooperation. This final report discusses areas in which…

Forest response to elevated CO2 is conserved across a broad range of productivity

Treesearch

R. Norby; E. DeLucia; B. Gielen; C. Calfapietra; C. Giardina; J. King; J. Ledford; H. McCarthy; D. Moore; R. Ceulemans; P. De Angelis; A. C. Finzi; D. F. Karnosky; M. E. Kubiske; M. Lukac; K. S. Pregitzer; G. E. Scarascia-Mugnozza; W. Schlesinger and R. Oren.

2005-01-01

Climate change predictions derived from coupled carbon-climate models are highly dependent on assumptions about feedbacks between the biosphere and atmosphere. One critical feedback occurs if C uptake by the biosphere increases in response to the fossil-fuel driven increase in atmospheric [CO2] ("CO2 fertilization...

Radiological risk assessment and biosphere modelling for radioactive waste disposal in Switzerland.

PubMed

Brennwald, M S; van Dorp, F

2009-12-01

Long-term safety assessments for geological disposal of radioactive waste in Switzerland involve the demonstration that the annual radiation dose to humans due to the potential release of radionuclides from the waste repository into the biosphere will not exceed the regulatory limit of 0.1 mSv. Here, we describe the simple but robust approach used by Nagra (Swiss National Cooperative for the Disposal of Radioactive Waste) to quantify the dose to humans as a result to time-dependent release of radionuclides from the geosphere into the biosphere. The model calculates the concentrations of radionuclides in different terrestrial and aquatic compartments of the surface environment. The fluxes of water and solids within the environment are the drivers for the exchange of radionuclides between these compartments. The calculated radionuclide concentrations in the biosphere are then used to estimate the radiation doses to humans due to various exposure paths (e.g. ingestion of radionuclides via drinking water and food, inhalation of radionuclides, external irradiation from radionuclides in soils). In this paper we also discuss recent new achievements and planned future work.

Atmospheric dynamics and bioregenerative technologies in a soil-based ecological life support system: Initial results from biosphere 2

NASA Astrophysics Data System (ADS)

Nelson, M.; Dempster, W.; Alvarez-Romo, N.; MacCallum, T.

1994-11-01

Biosphere 2 is the first man-made, soil-based, bioregenerative life support system to be developed and tested. The utilization and amendment of local space resources, e.g. martian soil or lunar regolith, for agricultural and other purposes will be necesary if we are to minimize the requirement for Earth materials in the creation of long-term off-planet bases and habitations. Several of the roles soil plays in Biosphere 2 are 1) for air purification 2) as a key component in created wetland systems to recycle human and animal wastes and 3) as nutrient base for a sustainable agricultural cropping program. Initial results from the Biosphere 2 closure experiment are presented. These include the accelerated cycling rates due to small reservoir sizes, strong diurnal and seasonal fluxes in atmospheric CO2, an unexpected and continuing decline in atmospheric oxygen, overall maintenance of low levels of trace gases, recycling of waste waters through biological regeneration systems, and operation of an agriculture designed to provide diverse and nutritionally adequate diets for the crew members.

Reconnecting to the biosphere.

PubMed

Folke, Carl; Jansson, Asa; Rockström, Johan; Olsson, Per; Carpenter, Stephen R; Chapin, F Stuart; Crépin, Anne-Sophie; Daily, Gretchen; Danell, Kjell; Ebbesson, Jonas; Elmqvist, Thomas; Galaz, Victor; Moberg, Fredrik; Nilsson, Måns; Osterblom, Henrik; Ostrom, Elinor; Persson, Asa; Peterson, Garry; Polasky, Stephen; Steffen, Will; Walker, Brian; Westley, Frances

2011-11-01

Humanity has emerged as a major force in the operation of the biosphere, with a significant imprint on the Earth System, challenging social-ecological resilience. This new situation calls for a fundamental shift in perspectives, world views, and institutions. Human development and progress must be reconnected to the capacity of the biosphere and essential ecosystem services to be sustained. Governance challenges include a highly interconnected and faster world, cascading social-ecological interactions and planetary boundaries that create vulnerabilities but also opportunities for social-ecological change and transformation. Tipping points and thresholds highlight the importance of understanding and managing resilience. New modes of flexible governance are emerging. A central challenge is to reconnect these efforts to the changing preconditions for societal development as active stewards of the Earth System. We suggest that the Millennium Development Goals need to be reframed in such a planetary stewardship context combined with a call for a new social contract on global sustainability. The ongoing mind shift in human relations with Earth and its boundaries provides exciting opportunities for societal development in collaboration with the biosphere--a global sustainability agenda for humanity.

Biological life-support systems for Mars mission.

PubMed

Gitelson, J I

1992-01-01

Mars mission like the Lunar base is the first venture to maintain human life beyond earth biosphere. So far, all manned space missions including the longest ones used stocked reserves and can not be considered egress from biosphere. Conventional path proposed by technology for Martian mission LSS is to use physical-chemical approaches proved by the experience of astronautics. But the problem of man living beyond the limits of the earth biosphere can be fundamentally solved by making a closed ecosystem for him. The choice optimum for a Mars mission LSS can be substantiated by comparing the merits and demerits of physical-chemical and biological principles without ruling out possible compromise between them. The work gives comparative analysis of ecological and physical-chemical principles for LSS. Taking into consideration universal significance of ecological problems with artificial LSS as a particular case of their solution, complexity and high cost of large-scale experiments with manned LSS, it would be expedient for these works to have the status of an International Program open to be joined. A program of making artificial biospheres based on preceding experience and analysis of current situation is proposed.

Comparing the effectiveness of monetary versus moral motives in environmental campaigning

NASA Astrophysics Data System (ADS)

Bolderdijk, J. W.; Steg, L.; Geller, E. S.; Lehman, P. K.; Postmes, T.

2013-04-01

Environmental campaigns often promote energy conservation by appealing to economic (for example, lower electricity bills) rather than biospheric concerns (for example, reduced carbon emissions), assuming that people are primarily motivated by economic self-interest. However, people also care about maintaining a favourable view of themselves (they want to maintain a `positive self-concept'), and may prefer to see themselves as `green' rather than `greedy'. Consequently, people may find economic appeals less attractive than biospheric appeals. Across two studies, participants indicated feeling better about biospheric (`Want to protect the environment? Check your car's tire pressure') than economic (`Want to save money? Check your car's tire pressure') tyre-check appeals. In a field experiment, we found that an economic tyre-check appeal (`Do you care about your finances? Get a free tire check') elicited significantly less compliance than parallel biospheric and neutral appeals. Together, these studies discredit the conventional wisdom that appealing to economic self-interest is the best way to secure behaviour change. At least in some cases, our studies suggest, this strategy is not effective.

Pharmaceutical Residues Affecting the UNESCO Biosphere Reserve Kristianstads Vattenrike Wetlands: Sources and Sinks.

PubMed

Björklund, Erland; Svahn, Ola; Bak, Søren; Bekoe, Samuel Oppong; Hansen, Martin

2016-10-01

This study is the first to investigate the pharmaceutical burden from point sources affecting the UNESCO Biosphere Reserve Kristianstads Vattenrike, Sweden. The investigated Biosphere Reserve is a >1000 km(2) wetland system with inflows from lakes, rivers, leachate from landfill, and wastewater-treatment plants (WWTPs). We analysed influent and treated wastewater, leachate water, lake, river, and wetland water alongside sediment for six model pharmaceuticals. The two WWTPs investigated released pharmaceutical residues at levels close to those previously observed in Swedish monitoring exercises. Compound-dependent WWTP removal efficiencies ranging from 12 to 100 % for bendroflumethiazide, oxazepam, atenolol, carbamazepine, and diclofenac were observed. Surface-water concentrations in the most affected lake were ≥100 ng/L for the various pharmaceuticals with atenolol showing the highest levels (>300 ng/L). A small risk assessment showed that adverse single-substance toxicity on aquatic organisms within the UNESCO Biosphere Reserve is unlikely. However, the effects of combinations of a large number of known and unknown pharmaceuticals, metals, and nutrients are still unknown.

The Effects of Recreation Experience, Environmental Attitude, and Biospheric Value on the Environmentally Responsible Behavior of Nature-Based Tourists

NASA Astrophysics Data System (ADS)

Lee, Tsung Hung; Jan, Fen-Hauh

2015-07-01

The scientific understanding of the recreation experience and the environmentally responsible behavior of nature-based tourists is limited. This study examines the relationship among the recreation experience, environmental attitude, biospheric value, and the general and site-specific environmentally responsible behavior of nature-based tourists in Taomi, Liuqiu Island, and Aowanda and Najenshan in Taiwan. A total of 1342 usable questionnaires were collected for this study. The empirical results indicate that the recreation experience influences biospheric value and environmental attitude; subsequently, it then indirectly influences the general and site-specific environmentally responsible behavior of nature-based tourists. Our theoretical behavioral model elucidates previously proposed but unexamined behavioral models among nature-based tourists, and it offers a theoretical framework for researchers, decision makers, managers, and tourists in the field of nature-based tourism. We conclude that when an individual participates in nature-based tourism as described here, these recreation experiences strengthen their environmental attitude and biospheric value, and consequently increase their engagement in both general and site-specific environmentally responsible behaviors.

The effects of recreation experience, environmental attitude, and biospheric value on the environmentally responsible behavior of nature-based tourists.

PubMed

Lee, Tsung Hung; Jan, Fen-Hauh

2015-07-01

The scientific understanding of the recreation experience and the environmentally responsible behavior of nature-based tourists is limited. This study examines the relationship among the recreation experience, environmental attitude, biospheric value, and the general and site-specific environmentally responsible behavior of nature-based tourists in Taomi, Liuqiu Island, and Aowanda and Najenshan in Taiwan. A total of 1342 usable questionnaires were collected for this study. The empirical results indicate that the recreation experience influences biospheric value and environmental attitude; subsequently, it then indirectly influences the general and site-specific environmentally responsible behavior of nature-based tourists. Our theoretical behavioral model elucidates previously proposed but unexamined behavioral models among nature-based tourists, and it offers a theoretical framework for researchers, decision makers, managers, and tourists in the field of nature-based tourism. We conclude that when an individual participates in nature-based tourism as described here, these recreation experiences strengthen their environmental attitude and biospheric value, and consequently increase their engagement in both general and site-specific environmentally responsible behaviors.

Harvesting the biosphere: the human impact.

PubMed

Smil, Vaclav

2011-01-01

The human species has evolved to dominate the biosphere: global anthropomass is now an order of magnitude greater than the mass of all wild terrestrial mammals. As a result, our dependence on harvesting the products of photosynthesis for food, animal feed, raw materials, and energy has grown to make substantial global impacts. During the past two millennia these harvests, and changes of land use due to deforestation and conversions of grasslands and wetlands, have reduced the stock of global terrestrial plant mass by as much as 45 percent, with the twentieth-century reduction amounting to more than 15 percent. Current annual harvests of phytomass have been a significant share of the global net primary productivity (NPP, the total amount of new plant tissues created by photosynthesis). Some studies put the human appropriation of NPP (the ratio of these two variables) as high as 40 percent but the measure itself is problematic. Future population growth and improved quality of life will result in additional claims on the biosphere, but options to accommodate these demands exist without severely compromising the irreplaceable biospheric services.

Heat transfer in porous medium embedded with vertical plate: Non-equilibrium approach - Part A

DOE Office of Scientific and Technical Information (OSTI.GOV)

Badruddin, Irfan Anjum; Quadir, G. A.

2016-06-08

Heat transfer in a porous medium embedded with vertical flat plate is investigated by using thermal non-equilibrium model. Darcy model is employed to simulate the flow inside porous medium. It is assumed that the heat transfer takes place by natural convection and radiation. The vertical plate is maintained at isothermal temperature. The governing partial differential equations are converted into non-dimensional form and solved numerically using finite element method. Results are presented in terms of isotherms and streamlines for various parameters such as heat transfer coefficient parameter, thermal conductivity ratio, and radiation parameter.

Simultaneous estimation of local-scale and flow path-scale dual-domain mass transfer parameters using geoelectrical monitoring

USGS Publications Warehouse

Briggs, Martin A.; Day-Lewis, Frederick D.; Ong, John B.; Curtis, Gary P.; Lane, John W.

2013-01-01

Anomalous solute transport, modeled as rate-limited mass transfer, has an observable geoelectrical signature that can be exploited to infer the controlling parameters. Previous experiments indicate the combination of time-lapse geoelectrical and fluid conductivity measurements collected during ionic tracer experiments provides valuable insight into the exchange of solute between mobile and immobile porosity. Here, we use geoelectrical measurements to monitor tracer experiments at a former uranium mill tailings site in Naturita, Colorado. We use nonlinear regression to calibrate dual-domain mass transfer solute-transport models to field data. This method differs from previous approaches by calibrating the model simultaneously to observed fluid conductivity and geoelectrical tracer signals using two parameter scales: effective parameters for the flow path upgradient of the monitoring point and the parameters local to the monitoring point. We use regression statistics to rigorously evaluate the information content and sensitivity of fluid conductivity and geophysical data, demonstrating multiple scales of mass transfer parameters can simultaneously be estimated. Our results show, for the first time, field-scale spatial variability of mass transfer parameters (i.e., exchange-rate coefficient, porosity) between local and upgradient effective parameters; hence our approach provides insight into spatial variability and scaling behavior. Additional synthetic modeling is used to evaluate the scope of applicability of our approach, indicating greater range than earlier work using temporal moments and a Lagrangian-based Damköhler number. The introduced Eulerian-based Damköhler is useful for estimating tracer injection duration needed to evaluate mass transfer exchange rates that range over several orders of magnitude.

Putting the Deep Biosphere on the Map for Oceanography Courses: Gas Hydrates As a Case Study for the Deep Biosphere

NASA Astrophysics Data System (ADS)

Sikorski, J. J.; Briggs, B. R.

2014-12-01

The ocean is essential for life on our planet. It covers 71% of the Earth's surface, is the source of the water we drink, the air we breathe, and the food we eat. Yet, the exponential growth in human population is putting the ocean and thus life on our planet at risk. However, based on student evaluations from our introductory oceanography course it is clear that our students have deficiencies in ocean literacy that impact their ability to recognize that the ocean and humans are inextricably connected. Furthermore, life present in deep subsurface marine environments is also interconnected to the study of the ocean, yet the deep biosphere is not typically covered in undergraduate oceanography courses. In an effort to improve student ocean literacy we developed an instructional module on the deep biosphere focused on gas hydrate deposits. Specifically, our module utilizes Google Earth and cutting edge research about microbial life in the ocean to support three inquiry-based activities that each explore different facets of gas hydrates (i.e. environmental controls, biologic controls, and societal implications). The relevant nature of the proposed module also makes it possible for instructors of introductory geology courses to modify module components to discuss related topics, such as climate, energy, and geologic hazards. This work, which will be available online as a free download, is a solid contribution toward increasing the available teaching resources focused on the deep biosphere for geoscience educators.

Aeolian Processes and the Biosphere

NASA Astrophysics Data System (ADS)

Ravi, Sujith; D'Odorico, Paolo; Breshears, David D.; Field, Jason P.; Goudie, Andrew S.; Huxman, Travis E.; Li, Junran; Okin, Gregory S.; Swap, Robert J.; Thomas, Andrew D.; Van Pelt, Scott; Whicker, Jeffrey J.; Zobeck, Ted M.

2011-08-01

Aeolian processes affect the biosphere in a wide variety of contexts, including landform evolution, biogeochemical cycles, regional climate, human health, and desertification. Collectively, research on aeolian processes and the biosphere is developing rapidly in many diverse and specialized areas, but integration of these recent advances is needed to better address management issues and to set future research priorities. Here we review recent literature on aeolian processes and their interactions with the biosphere, focusing on (1) geography of dust emissions, (2) impacts, interactions, and feedbacks, (3) drivers of dust emissions, and (4) methodological approaches. Geographically, dust emissions are highly spatially variable but also provide connectivity at global scales between sources and effects, with “hot spots” being of particular concern. Recent research reveals that aeolian processes have impacts, interactions, and feedbacks at a variety of scales, including large-scale dust transport and global biogeochemical cycles, climate mediated interactions between atmospheric dust and ecosystems, impacts on human health, impacts on agriculture, and interactions between aeolian processes and dryland vegetation. Aeolian dust emissions are driven largely by, in addition to climate, a combination of soil properties, soil moisture, vegetation and roughness, biological and physical crusts, and disturbances. Aeolian research methods span laboratory and field techniques, modeling, and remote sensing. Together these integrated perspectives on aeolian processes and the biosphere provide insights into management options and aid in identifying research priorities, both of which are increasingly important given that global climate models predict an increase in aridity in many dryland systems of the world.

A new calibration of the effective scattering albedo and soil roughness parameters in the SMOS SM retrieval algorithm

NASA Astrophysics Data System (ADS)

Fernandez-Moran, R.; Wigneron, J.-P.; De Lannoy, G.; Lopez-Baeza, E.; Parrens, M.; Mialon, A.; Mahmoodi, A.; Al-Yaari, A.; Bircher, S.; Al Bitar, A.; Richaume, P.; Kerr, Y.

2017-10-01

This study focuses on the calibration of the effective vegetation scattering albedo (ω) and surface soil roughness parameters (HR, and NRp, p = H,V) in the Soil Moisture (SM) retrieval from L-band passive microwave observations using the L-band Microwave Emission of the Biosphere (L-MEB) model. In the current Soil Moisture and Ocean Salinity (SMOS) Level 2 (L2), v620, and Level 3 (L3), v300, SM retrieval algorithms, low vegetated areas are parameterized by ω = 0 and HR = 0.1, whereas values of ω = 0.06 - 0.08 and HR = 0.3 are used for forests. Several parameterizations of the vegetation and soil roughness parameters (ω, HR and NRp, p = H,V) were tested in this study, treating SMOS SM retrievals as homogeneous over each pixel instead of retrieving SM over a representative fraction of the pixel, as implemented in the operational SMOS L2 and L3 algorithms. Globally-constant values of ω = 0.10, HR = 0.4 and NRp = -1 (p = H,V) were found to yield SM retrievals that compared best with in situ SM data measured at many sites worldwide from the International Soil Moisture Network (ISMN). The calibration was repeated for collections of in situ sites classified in different land cover categories based on the International Geosphere-Biosphere Programme (IGBP) scheme. Depending on the IGBP land cover class, values of ω and HR varied, respectively, in the range 0.08-0.12 and 0.1-0.5. A validation exercise based on in situ measurements confirmed that using either a global or an IGBP-based calibration, there was an improvement in the accuracy of the SM retrievals compared to the SMOS L3 SM product considering all statistical metrics (R = 0.61, bias = -0.019 m3 m-3, ubRMSE = 0.062 m3 m-3 for the IGBP-based calibration; against R = 0.54, bias = -0.034 m3 m-3 and ubRMSE = 0.070 m3 m-3 for the SMOS L3 SM product). This result is a key step in the calibration of the roughness and vegetation parameters in the operational SMOS retrieval algorithm. The approach presented here is the core of a new forthcoming SMOS optimized SM product.

Steady boundary layer slip flow along with heat and mass transfer over a flat porous plate embedded in a porous medium.

PubMed

Aziz, Asim; Siddique, J I; Aziz, Taha

2014-01-01

In this paper, a simplified model of an incompressible fluid flow along with heat and mass transfer past a porous flat plate embedded in a Darcy type porous medium is investigated. The velocity, thermal and mass slip conditions are utilized that has not been discussed in the literature before. The similarity transformations are used to transform the governing partial differential equations (PDEs) into a nonlinear ordinary differential equations (ODEs). The resulting system of ODEs is then reduced to a system of first order differential equations which was solved numerically by using Matlab bvp4c code. The effects of permeability, suction/injection parameter, velocity parameter and slip parameter on the structure of velocity, temperature and mass transfer rates are examined with the aid of several graphs. Moreover, observations based on Schmidt number and Soret number are also presented. The result shows, the increase in permeability of the porous medium increase the velocity and decrease the temperature profile. This happens due to a decrease in drag of the fluid flow. In the case of heat transfer, the increase in permeability and slip parameter causes an increase in heat transfer. However for the case of increase in thermal slip parameter there is a decrease in heat transfer. An increase in the mass slip parameter causes a decrease in the concentration field. The suction and injection parameter has similar effect on concentration profile as for the case of velocity profile.

Steady Boundary Layer Slip Flow along with Heat and Mass Transfer over a Flat Porous Plate Embedded in a Porous Medium

PubMed Central

Aziz, Asim; Siddique, J. I.; Aziz, Taha

2014-01-01

In this paper, a simplified model of an incompressible fluid flow along with heat and mass transfer past a porous flat plate embedded in a Darcy type porous medium is investigated. The velocity, thermal and mass slip conditions are utilized that has not been discussed in the literature before. The similarity transformations are used to transform the governing partial differential equations (PDEs) into a nonlinear ordinary differential equations (ODEs). The resulting system of ODEs is then reduced to a system of first order differential equations which was solved numerically by using Matlab bvp4c code. The effects of permeability, suction/injection parameter, velocity parameter and slip parameter on the structure of velocity, temperature and mass transfer rates are examined with the aid of several graphs. Moreover, observations based on Schmidt number and Soret number are also presented. The result shows, the increase in permeability of the porous medium increase the velocity and decrease the temperature profile. This happens due to a decrease in drag of the fluid flow. In the case of heat transfer, the increase in permeability and slip parameter causes an increase in heat transfer. However for the case of increase in thermal slip parameter there is a decrease in heat transfer. An increase in the mass slip parameter causes a decrease in the concentration field. The suction and injection parameter has similar effect on concentration profile as for the case of velocity profile. PMID:25531301

Exploration of a Subsurface Biosphere in a Volcanic Massive Sulfide: Results of the Mars Analog Rio Tinto Drilling Experiment

NASA Astrophysics Data System (ADS)

Stoker, C. R.; Stevens, T.; Amils, R.; Fernandez, D.

2005-12-01

Biological systems on Earth require three key ingredients-- liquid water, an energy source, and a carbon source, that are found in very few extraterrestrial environments. Previous examples of independent subsurface ecosystems have been found only in basalt aquifers. Such lithotrophic microbial ecosystems (LME) have been proposed as models for steps in the early evolution of Earth's biosphere and for potential biospheres on other planets where the surface is uninhabitable, such as Mars and Europa.. The Mars Analog Rio Tinto Experiment (MARTE) has searched in a volcanic massive sulfide deposit in Rio Tinto Spain for a subsurface biosphere capable of living without sunlight or oxygen and found a subsurface ecosystem driven by the weathering of the massive sulfide deposit (VMS) in which the rock matrix provides sufficient resources to support microbial metabolism, including the vigorous production of H2 by water-rock interactions. Microbial production of methane and sulfate occurred in the sulfide orebody and microbial production of methane and hydrogen sulfide continued in an anoxic plume downgradient from the sulfide ore. Organic carbon concentrations in the parent rock were too low to support microbes. The Rio Tinto system thus represents a new type of subsurface ecosystem with strong relevance for exobiological studies. Commercial drilling was used to reach the aquifer system at 100 m depth and conventional laboratory techniques were used to identify and characterize the biosphere. Then, the life search strategy that led to successful identification of this biosphere was applied to the development of a robotic drilling, core handling, inspection, subsampling, and life detection system built on a prototype planetary lander that was deployed in Rio Tinto Spain in September 2005 to test the capability of a robotic drilling system to search for subsurface life. A remote science team directed the simulation and analyzed the data from the MARTE robotic drill. The results of this experiment have important implications for the strategy for searching for life on Mars.

“Modular Biospheres” New testbed platforms for public environmental education and research

NASA Astrophysics Data System (ADS)

Nelson, M.; Dempster, W. F.; Allen, J. P.

This paper will review the potential of a relatively new type of testbed platform for environmental education and research because of the unique advantages resulting from their material closure and separation from the outside environment. These facilities which we term "modular biospheres", have emerged from research centered on space life support research but offer a wider range of application. Examples of this type of facility include the Bios-3 facility in Russia, the Japanese CEEF (Closed Ecological Experiment Facility), the NASA Kennedy Space Center Breadboard facility, the Biosphere 2 Test Module and the Laboratory Biosphere. Modular biosphere facilities offer unique research and public real-time science education opportunities. Ecosystem behavior can be studied since initial state conditions can be precisely specified and tracked over different ranges of time. With material closure (apart from very small air exchange rate which can be determined), biogeochemical cycles between soil and soil microorganisms, water, plants, and atmosphere can be studied in detail. Such studies offer a major advance from studies conducted with phytotrons which because of their small size, limit the number of organisms to a very small number, and which crucially do not have a high degree of atmospheric, water and overall material closure. Modular biospheres take advantage of the unique properties of closure, as representing a distinct system "metabolism" and therefore are essentially a "mini-world". Though relatively large in comparison with most phytotrons and ecological microcosms, which are now standard research and educational tools, modular biospheres are small enough that they can be economically reconfigured to reflect a changing research agenda. Some design elements include lighting via electric lights and/or sunlight, hydroponic or soil substrate for plants, opaque or glazed structures, and variable volume chambers or other methods to handle atmospheric pressure differences between the facility and the outside environment.

Toward Reducing Uncertainties in Biospheric Carbon Uptake in the American West: An Atmospheric Perspective

NASA Astrophysics Data System (ADS)

Lin, J. C.; Stephens, B. B.; Mallia, D.; Wu, D.; Jacobson, A. R.

2015-12-01

Despite the need for an understanding of terrestrial biospheric carbon fluxes to account for carbon cycle feedbacks and predict future CO2 concentrations, knowledge of such fluxes at the regional scale remains poor. This is particularly true in mountainous areas, where lack of observations combined with difficulties in their interpretation lead to significant uncertainties. Yet mountainous regions are also where significant forest cover and biomass are found—areas that have the potential to serve as carbon sinks. In particular, understanding carbon fluxes in the American West is of critical importance for the U.S. carbon budget, as the large area and biomass indicate potential for carbon sequestration. However, disturbances such as drought, insect outbreak, and wildfires in this region can introduce significant perturbations to the carbon cycle and thereby affect the amount of carbon sequestered by vegetation in the Rockies. To date, there have been few atmospheric CO2 observations in the American Rockies due to a combination of difficulties associated with logistics and interpretation of the measurements in the midst of complex terrain. Among the few sites are those associated with NCAR's Regional Atmospheric Continuous CO2 Network in the Rocky Mountains (Rocky RACCOON). As CO2 observations in mountainous areas increase in the future, it is imperative that they can be properly interpreted to yield information about biospheric carbon fluxes. In this paper, we will present CO2 observations from RACCOON, along with atmospheric simulations that attempt to extract information about biospheric carbon fluxes in the Western U.S. from these observations. We show that atmospheric models can significantly misinterpret the CO2 observations, leading to large errors in the retrieved biospheric fluxes, due to erroneous atmospheric flows. Recommendations for ways to minimize such errors and properly link the CO2 concentrations to biospheric fluxes are discussed.

Evaluation of simulated biospheric carbon dioxide fluxes and atmospheric concentrations using global in situ observations

NASA Astrophysics Data System (ADS)

Philip, S.; Johnson, M. S.; Potter, C. S.; Genovese, V. B.

2016-12-01

Atmospheric mixing ratios of carbon dioxide (CO2) are largely controlled by anthropogenic emission sources and biospheric sources/sinks. Global biospheric fluxes of CO2 are controlled by complex processes facilitating the exchange of carbon between terrestrial ecosystems and the atmosphere. These processes which play a key role in these terrestrial ecosystem-atmosphere carbon exchanges are currently not fully understood, resulting in large uncertainties in the quantification of biospheric CO2 fluxes. Current models with these inherent deficiencies have difficulties simulating the global carbon cycle with high accuracy. We are developing a new modeling platform, GEOS-Chem-CASA by integrating the year-specific NASA-CASA (National Aeronautics and Space Administration - Carnegie Ames Stanford Approach) biosphere model with the GEOS-Chem (Goddard Earth Observation System-Chemistry) chemical transport model to improve the simulation of atmosphere-terrestrial ecosystem carbon exchange. We use NASA-CASA to explicitly represent the exchange of CO2 between terrestrial ecosystem and atmosphere by replacing the baseline GEOS-Chem land net CO2 flux and forest biomass burning CO2 emissions. We will present the estimation and evaluation of these "bottom-up" land CO2 fluxes, simulated atmospheric mixing ratios, and forest disturbance changes over the last decade. In addition, we will present our initial comparison of atmospheric column-mean dry air mole fraction of CO2 predicted by the model and those retrieved from NASA's OCO-2 (Orbiting Carbon Observatory-2) satellite instrument and model-predicted surface CO2 mixing ratios with global in situ observations. This evaluation is the first step necessary for our future work planned to constrain the estimates of biospheric carbon fluxes through "top-down" inverse modeling, which will improve our understanding of the processes controlling atmosphere-terrestrial ecosystem greenhouse gas exchanges, especially over regions which lack in situ observations.

B33C-0612: Evaluation of Simulated Biospheric Carbon Dioxide Fluxes and Atmospheric Concentrations Using Global in Situ Observations

NASA Technical Reports Server (NTRS)

Philip, Sajeev; Johnson, Matthew S.; Potter, Christopher S.; Genovese, Vanessa

2016-01-01

Atmospheric mixing ratios of carbon dioxide (CO2) are largely controlled by anthropogenic emission sources and biospheric sources/sinks. Global biospheric fluxes of CO2 are controlled by complex processes facilitating the exchange of carbon between terrestrial ecosystems and the atmosphere. These processes which play a key role in these terrestrial ecosystem-atmosphere carbon exchanges are currently not fully understood, resulting in large uncertainties in the quantification of biospheric CO2 fluxes. Current models with these inherent deficiencies have difficulties simulating the global carbon cycle with high accuracy. We are developing a new modeling platform, GEOS-Chem-CASA by integrating the year-specific NASA-CASA (National Aeronautics and Space Administration - Carnegie Ames Stanford Approach) biosphere model with the GEOS-Chem (Goddard Earth Observation System-Chemistry) chemical transport model to improve the simulation of atmosphere-terrestrial ecosystem carbon exchange. We use NASA-CASA to explicitly represent the exchange of CO2 between terrestrial ecosystem and atmosphere by replacing the baseline GEOS-Chem land net CO2 flux and forest biomass burning CO2 emissions. We will present the estimation and evaluation of these "bottom-up" land CO2 fluxes, simulated atmospheric mixing ratios, and forest disturbance changes over the last decade. In addition, we will present our initial comparison of atmospheric column-mean dry air mole fraction of CO2 predicted by the model and those retrieved from NASA's OCO-2 (Orbiting Carbon Observatory-2) satellite instrument and model-predicted surface CO2 mixing ratios with global in situ observations. This evaluation is the first step necessary for our future work planned to constrain the estimates of biospheric carbon fluxes through "top-down" inverse modeling, which will improve our understanding of the processes controlling atmosphere-terrestrial ecosystem greenhouse gas exchanges, especially over regions which lack in situ observations.

[Microbes on the edge of global biosphere].

PubMed

Naganuma, T

2000-12-01

The search for life on the edge of global biosphere is a frontier to bridge conventional bio/ecology and exo/astrobiology. This communication reviews the foci of microbiological studies on the inhabitants of the selected "edges", i.e., deep-sea, deep subsurface and Antarctic habitats. The deep-sea is characterized as the no-light (non-photosynthetic) habitat, and the primary production is mostly due to the chemosynthetic autotrophy at the hydrothermal vents and methane-rich seeps. Formation of the chemosynthesis-dependent animal communities in the deep leads to the idea that such communities may be found in "ocean" of the Jovian satellite, Europa. The oxygen minimal layer (OML) in mid-water provides another field of deep-sea research. Modern OML is a relatively thin layer, found between the water depth of 200 and 1000 m, but was much thicker during the periods of oceanic anoxia events (OAEs) in the past. The history of oceanic biosphere is regarded as the cycle of OAE and non-OAE periods, and the remnants of the past OAEs may be seen in the modem OML. Anoxic (no-O2) condition is also characteristic of deep subsurface biosphere. Microorganisms in deep subsurface biosphere exploit every available oxidant, or terminal electron acceptor (TEA), for anaerobic respiration. Sulfate, nitrate, iron (III) and CO2 are the representative TEAs in the deep subsurface. Subsurface of hydrothermal vents, or sub-vent biosphere, may house brine (high salt) habitats and halophilic microorganisms. Some sub-vent halophiles were phylogenetically closely similar to the ones found in the Antarctic habitats which are extremely dry by the liophilizing climate. Below the 3000-4000 m-thick glacier on Antarctica, there have been >70 lakes with liquid water located. One of such sub-glacial lakes, Lake Vostok, has been a target of "life in extreme environments" and is about to be drill-penetrated for microbiological studies. These 'microbiological platforms' will provide new knowledge about the diversity and potential of the Earth's life and facilitate the capability of astrobiologial exploration.

The direction of bilateral transfer depends on the performance parameter.

PubMed

Pan, Zhujun; van Gemmert, Arend W A

2013-10-01

To acquire a more comprehensive understanding of the learning benefits associated with bilateral transfer and to gain knowledge of possible mechanisms behind bilateral transfer, we investigated the transfer direction of several parameters which are assumed to represent important features of movement control in a visuo-motor task. During the study, participants learned a multidirectional point-to-point drawing task in which the visual feedback was rotated 45° and the gain was increased. Performance changes of the untrained hand in movement time, trajectory length, normalized jerk, initial direction error, ratio of the primary sub-movement time to the total movement time, and the accuracy of the aiming movement after the primary sub-movement were investigated as indices of learning from bilateral transfer. The results showed that performance parameters related to the initial production of the movement, such as the initial direction, ratio of primary sub-movement to the total movement time, and movement accuracy after the primary sub-movement, only transferred to the non-dominant, while hand performance variables related to the overall outcome, such as movement duration, movement smoothness, and trajectory length, transferred in both directions. The findings of the current study support the basic principle of the "dynamic dominance model" because it is suggested that overall improvements in the non-dominant system are controlled by trajectory parameters in visuo-motor tasks, which resulted in transference of the afore mentioned production parameters to rather occur to the non-dominant hand as opposed to transference to the dominant hand. Published by Elsevier B.V.

The past, present and future supernova threat to Earth's biosphere

NASA Astrophysics Data System (ADS)

Beech, Martin

2011-12-01

A brief review of the threat posed to Earth's biosphere via near-by supernova detonations is presented. The expected radiation dosage, cosmic ray flux and expanding blast wave collision effects are considered, and it is argued that a typical supernova must be closer than ˜10-pc before any appreciable and potentially harmful atmosphere/biosphere effects are likely to occur. In contrast, the critical distance for Gamma-ray bursts is of order 1-kpc. In spite of the high energy effects potentially involved, the geological record provides no clear-cut evidence for any historic supernova induced mass extinctions and/or strong climate change episodes. This, however, is mostly a reflection of their being numerous possible (terrestrial and astronomical) forcing mechanisms acting upon the biosphere and the difficulty of distinguishing between competing scenarios. Key to resolving this situation, it is suggested, is the development of supernova specific extinction and climate change linked ecological models. Moving to the future, we estimate that over the remaining lifetime of the biosphere (˜2 Gyr) the Earth might experience 1 GRB and 20 supernova detonations within their respective harmful threat ranges. There are currently at least 12 potential pre-supernova systems within 1-kpc of the Sun. Of these systems IK Pegasi is the closest Type Ia pre-supernova candidate and Betelgeuse is the closest potential Type II supernova candidate. We review in some detail the past, present and future behavior of these two systems. Developing a detailed evolutionary model we find that IK Pegasi will likely not detonate until some 1.9 billion years hence, and that it affords absolutely no threat to Earth's biosphere. Betelgeuse is the closest, reasonably well understood, pre-supernova candidate to the Sun at the present epoch, and may undergo detonation any time within the next several million years. The stand-off distance of Betelgeuse at the time of its detonation is estimated to fall between 150 and 300-pc—again, affording no possible threat to Earth's biosphere. Temporally, the next most likely, close, potential Type Ic supernova to the Sun is the Wolf-Rayet star within the γ 2 Velorum binary system located at least 260-pc away. It is suggested that evidence relating to large-scale astroengineering projects might fruitfully be looked for in those regions located within 10 to 30-pc of any pre-supernova candidate system.

Implementation of the geoethics principal to environmental technologies by Biogeosystem Technique

NASA Astrophysics Data System (ADS)

Batukaev, Abdulmalik; Kalinitchenko, Valery; Minkina, Tatiana; Mandzhieva, Saglara; Sushkova, Svetlana

2017-04-01

The uncertainty and degradation of biosphere is a result of outdated industrial technologies. The incorrect principals of the nature resources use paradigm are to be radically changed corresponding to principals of Geoethics. Technological dead-end is linked to Philosophy of Technology. The organic protection and imitation of natural patterns are till now the theoretical base of technology. The technological and social determinism are proposed as the "inevitable" for humankind. One is forced to believe that the only way for humanity is to agree that the outdated way of technical development is the only possibility for humankind to survive. But rough imitation as a method of outdated technological platform is fruitless now. Survival under practice of industrial technology platform now has become extremely dangerous. The challenge for humanity is to overcome the chain of environmental hazards of agronomy, irrigation, industry, and other human activities in biosphere, which awkwardly imitate the natural processes: plowing leads to degradation of soil and greenhouse gases emission; irrigation leads to excessive moistening and degradation of soil, landscape, greenhouse gases emission, loss of freshwater - the global deficit; waste utilization leads to greenhouse gases emission, loss of oxigen and other ecological hazards. The fundamentally new technologies are to be generates for development of biosphere, food and resources renewing. Aristotle told that technique can go beyond nature and implement "what nature can't bring to a finish." To overcome fundamental shortcomings of industrial technologies, incorrect land use we propose the Biogeosystem Technique (BGT*) for biosphere sustainability. The BGT* key point is transcendent approach (not imitating of the natural processes) - new technical solutions for biosphere - soil construction, the fluxes of energy, matter, and water control and biological productivity of terrestrial systems. Intra-soil milling which provides the new soil dispersed system synthesis - biological productivity of soil increases twice; intra-soil pulse discrete plants watering which permits to save the freshwater - global deficit - up to 20 times, protect the soil and landscape from excess water, and optimize soil water regime for higher plant's productivity; environmentally safe return of the substances into the active stage of biosphere during synthesis of soil dispersed system and (or) intra-soil pulse discrete plant watering for proper waste recycling. BGT* optimizes an anthropogenic carbon cycle of the Earth, reduces the greenhouse gases emission, implements conditions for green economy, provides an extension of the active area of the biosphere on Earth, water saving, soil and land health. The additional biological product, including food, raw materials and biofuels will be obtained. BGT* can be implemented on the basis of robotics providing cost savings compared to existing industrial technologies of agronomy and environment management. BGT* is the implementation of Geoethics in environmentally safe, productive and low cost technologies of Biosphere at the stage of Noosphere.

Biogeosystem technique as a method to overcome the Biological and Environmental Hazards of modern Agricultural, Irrigational and Technological Activities

NASA Astrophysics Data System (ADS)

Kalinitchenko, Valery; Batukaev, Abdulmalik; Zinchenko, Vladimir; Zarmaev, Ali; Magomadov, Ali; Chernenko, Vladimir; Startsev, Viktor; Bakoev, Serojdin; Dikaev, Zaurbek

2014-05-01

Modern challenge for humanity is to replace the paradigm of nature use and overcome environmental hazards of agronomy, irrigation, industry, and other human activities in biosphere. It is utterly reasonable to stop dividing biosphere on shares - the human habitat and the environment. In the 21st century it is an outdated anthropocentrism. Contradicting himself to biosphere Humankind has the problems. The new paradigm of biosphere control by methods of Biogeosystem technique is on agenda of Humankind. Key directions of Biogeosystem technique. Tillage. Single rotary milling 20…30-50…60 sm soil layer optimizes the evolution and environment of soil, creates a favorable conditions for the rhizosphere, increases the biological productivity of biosphere by 30-50% compared to the standard agricultural practices for the period up to 40 years. Recycle material. Recycling of mineral and organic substances in soil layer of 20…30-50…60 sm in rotary milling soil processing provides wastes clean return to biosphere. Direct intrasoil substances synthesis. Environmentally friendly robot wasteless nanotechnology provides direct substances synthesis, including fertilizers, inside the soil. It eliminates the prerequisites of the wastes formation under standard industrial technologies. Selective substance's extraction from soil. Electrochemical robotic nanotechnology provides selective substances extraction from soil. The technology provides recovery, collection and subsequent safe industrial use of extracted substances out of landscape. Saving fresh water. An important task is to save fresh water in biosphere. Irrigation spends water 4-5 times more of biological requirements of plants, leads to degradation of soil and landscape. The intrasoil pulse continuous-discrete paradigm of irrigation is proposed. It provides the soil and landscape conservation, increases the biological productivity, save the fresh water up to 10-20 times. The subsurface soil rotary processing and intrasoil pulsed continuous-discrete irrigation provide environmentally safe disposal of municipal, industrial, biological and agricultural wastes. Hazardous chemical and biological agents are under the soil surface. It provided a medical and veterinary safety of environment. Biogeosystem technic controls the equilibria in the soil and soil solution, prevents excessive mineralization of organic matter in the surface layers of soil. Simultaneously a soil chemical reduction excluded, biological substance do not degrade to gases. Products of organic matter decomposition are directed to the food chain, 100% waste recycling is obtained. Biogeosystems technique allows producing more biological products hence to recycle excessive amount of man-made CO2 and other substances. Biogeosystems technique increases the rate of photosynthesis of the biosphere, the degree of air ionization. This enhances the formation of rains over land, ensures stability of the ionosphere, magnetosphere and atmosphere of Earth. The nowadays technologies allow applying technical solutions based on Biogeosystem technique, there is unique opportunity to accelerate the noosphere new technological platform.

Loss of nutrients from terrestrial ecosystems to streams and the atmosphere following land use change in Amazonia

NASA Astrophysics Data System (ADS)

Davidson, Eric A.; Neill, Christopher; Krusche, Alex V.; Ballester, Victoria V. R.; Markewitz, Daniel; Figueiredo, Ricardo de O.

Rates of deforestation in the Amazon region have been accelerating, but the quantity and timing of nutrient losses from forested and deforested ecosystems are poorly understood. This paper investigates the broad variation in soil properties of the Amazon Basin as they influence transfers of plant nutrients from the terrestrial biosphere to the atmosphere and the aquatic biosphere. The dominant lowland soils are highly weathered Oxisols and Ultisols, but significant areas of Alfisols also exist, resulting in a wide range of weatherable primary minerals. Despite this considerable variation among Amazonian soils, a common feature in most mature lowland Amazonian forests is a conservative P cycle and excess N availability. In cattle pastures and secondary forests, however, low rates of internal terrestrial N cycling, low N export to streams, and low gaseous N emissions from soils are common, due to significant previous losses of N through repeated fire. Export of P to streams may increase or remain nearly undetectable after forest-to-pasture conversion, depending on soil type. Oxisols exhibit very low P export, whereas increased P export to pasture streams has been observed in Ultisols of western Amazonia. Calcium is mostly retained in terrestrial ecosystems following deforestation, although increased inputs to streams can be detected when background fluxes are naturally low. Because soil mineralogy and soil texture are both variable and important, the effects of land-use change on nutrient export to aquatic ecosystems and to the atmosphere must be understood within the context of varying soil properties across the Amazon Basin.

Biodiversity matters in feedbacks between climate change and air quality: a study using an individual-based model.

PubMed

Wang, Bin; Shuman, Jacquelyn; Shugart, Herman H; Lerdau, Manuel T

2018-03-30

Air quality is closely associated with climate change via the biosphere because plants release large quantities of volatile organic compounds (VOC) that mediate both gaseous pollutants and aerosol dynamics. Earlier studies, which considered only leaf physiology and simply scale up from leaf-level enhancements of emissions, suggest that climate warming enhances whole forest VOC emissions, and these increased VOC emissions aggravate ozone pollution and secondary organic aerosol formation. Using an individual-based forest VOC emissions model, UVAFME-VOC, that simulates system-level emissions by explicitly simulating forest community dynamics to the individual tree level, ecological competition among the individuals of differing size and age, and radiative transfer and leaf function through the canopy, we find that climate warming only sometimes stimulates isoprene emissions (the single largest source of non-methane hydrocarbon) in a southeastern U.S. forest. These complex patterns result from the combination of higher temperatures' stimulating emissions at the leaf level but decreasing the abundance of isoprene-emitting taxa at the community level by causing a decline in the abundance of isoprene-emitting species (Quercus spp.). This ecological effect eventually outweighs the physiological one, thus reducing overall emissions. Such reduced emissions have far-reaching implications for the climate-air-quality relationships that have been established on the paradigm of warming-enhancement VOC emissions from vegetation. This local scale modeling study suggests that community ecology rather than only individual physiology should be integrated into future studies of biosphere-climate-chemistry interactions. © 2018 by the Ecological Society of America.

Predicting Summer Dryness Under a Warmer Climate: Modeling Land Surface Processes in the Midwestern United States

NASA Astrophysics Data System (ADS)

Winter, J. M.; Eltahir, E. A.

2009-12-01

One of the most significant impacts of climate change is the potential alteration of local hydrologic cycles over agriculturally productive areas. As the world’s food supply continues to be taxed by its burgeoning population, a greater percentage of arable land will need to be utilized and land currently producing food must become more efficient. This study seeks to quantify the effects of climate change on soil moisture in the American Midwest. A series of 24-year numerical experiments were conducted to assess the ability of Regional Climate Model Version 3 coupled to Integrated Biosphere Simulator (RegCM3-IBIS) and Biosphere-Atmosphere Transfer Scheme 1e (RegCM3-BATS1e) to simulate the observed hydroclimatology of the midwestern United States. Model results were evaluated using NASA Surface Radiation Budget, NASA Earth Radiation Budget Experiment, Illinois State Water Survey, Climate Research Unit Time Series 2.1, Global Soil Moisture Data Bank, and regional-scale estimations of evapotranspiration. The response of RegCM3-IBIS and RegCM3-BATS1e to a surrogate climate change scenario, a warming of 3oC at the boundaries and doubling of CO2, was explored. Precipitation increased significantly during the spring and summer in both RegCM3-IBIS and RegCM3-BATS1e, leading to additional runoff. In contrast, enhancement of evapotranspiration and shortwave radiation were modest. Soil moisture remained relatively unchanged in RegCM3-IBIS, while RegCM3-BATS1e exhibited some fall and winter wetting.

Weather summaries for Coram Experimental Forest, northwestern Montana-an International Biosphere Reserve

Treesearch

Roger D. Hungerford; Joyce A. Schlieter

1984-01-01

Presents weather data summaries (1934-82) for most of the weather stations within the Coram Experimental Forest (a Biosphere Reserve) in northwestern Montana and for three stations adjacent to the Forest. These data aid in the interpretation of silvicultural and other biological research, particularly the relationships of climatological variations to forest growth and...

Stream denitrification across biomes and its response to anthropogenic nitrate loading

Treesearch

Patrick J Mulholland; Ashely M. Helton; Geoffrey C. Poole; Robert O. Hall; Stephen K. Hamilton; Bruce J. Peterson; Jennifer L. Tank; Linda R. Ashkenas; Lee W. Cooper; Clifford N. Dahm; Walter K. Dodds; Stuart E.G. Findlay; Stanley V. Gregory; Nancy B. Grimm; Sherri L. Johnson; William H. McDowell; Judy L. Meyer; H. Maurice Valett; Jackson R. Webster; Clay P. Arango; Jake J. Beaulieu; Melody J. Bernot; Amy J. Burgin; Chelsea L. Crenshaw; Laura T. Johnson; B.R. Niederlehner; Jonathan M. O' Brien; Jody D. Potter; Richard W. Sheibley; Daniel J. Sobota; Suzanne M. Thomas

2008-01-01

Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing, and terrestrial ecosystems are becoming increasingly nitrogen-saturated, causing more bioavailable nitrogen to enter groundwater and surface waters. Large-scale nitrogen budgets show that an average of about 20 to 25 percent of the nitrogen added to the biosphere is exported from rivers to...

Environmental Art as an Innovative Medium for Environmental Education in Biosphere Reserves

ERIC Educational Resources Information Center

Marks, M.; Chandler, L.; Baldwin, C.

2017-01-01

A key goal of Biosphere Reserves (BR) is to foster environmental education for sustainable development. In this study we systematically analyse two cases in which environmental art is used as a mechanism to engage communities in "building environmental understanding", in Noosa BR in Australia and North Devon BR in the United Kingdom.…

The Loss of Genetic Diversity: An Impending Global Issue.

ERIC Educational Resources Information Center

Pierce, James P.

Definitions of biosphere and ecosystem are provided as the basis for understanding a problem that threatens to become (or already is) a global issue, namely, human activity which results in reducing the diversity of life forms present in the biosphere as an ecosystem. Two aspects of this problem are: (1) the growth of human populations worldwide…

Lunar subsurface architecture enhanced by artificial biosphere concepts

NASA Technical Reports Server (NTRS)

Klassi, Jason D.; Rocha, Carlos J.; Carr, Charles A.

1992-01-01

The integration of artificial biosphere technology with subselene architecture can create a life-enhancing, productive habitat that is safe from solar radiation and extreme temperature fluctuations while maximizing resources brought from Earth and derived from lunar regolith. In the short term, the resulting biotectural (biosphere and architectural) designs will not only make the structures more habitable, productive, and manageable, but will ultimately provide the self-sufficiency factors necessary for the mature lunar settlement. From a long-term perspective, this biotecture approach to astronautics and extraterrestrial development (1) helps reduce mass lift requirements, (2) contributes to habitat self-sufficiency, and (3) actualizes at least one philosophy of solar system exploration, which is to exploit nonterrestrial resources in an effort to conserve our natural resources on this planet.

C-LAMP Subproject Description:Climate Forcing by the Terrestrial Biosphere During the Second Half of the 20th Century

DOE Office of Scientific and Technical Information (OSTI.GOV)

Covey, Curt; Hoffman, Forrest

2008-10-02

This project will quantify selected components of climate forcing due to changes in the terrestrial biosphere over the period 1948-2004, as simulated by the climate / carboncycle models participating in C-LAMP (the Carbon-Land Model Intercomparison Project; see http://www.climatemodeling.org/c-lamp). Unlike other C-LAMP projects that attempt to close the carbon budget, this project will focus on the contributions of individual biomes in terms of the resulting climate forcing. Bala et al. (2007) used a similar (though more comprehensive) model-based technique to assess and compare different components of biospheric climate forcing, but their focus was on potential future deforestation rather than the historicalmore » period.« less

[Is there a connection between biodiversity and the greenhouse effect].

PubMed

Rozanov, S I

1998-01-01

It was discussed the role of biodiversity in ecosystems capacity to control CO2 in atmosphere as the main reason not only of "greenhouse effect" but "greenhouse catastrophe". The necessity to perfect the preventive measures has been defined by time factor. This time may be so little for completing the evolution theory and models of biosphere management. The temps of contemporaneous species extinction exceed two orders as minimum ones how it has been known from planet history. It doesn't permit to discharge that evolutional process will be successful to create organisms which have been capable to stabilize biosphere in conditions of its changing status. It's possible that such change may be provocated with the crisis in civilization-biosphere interrelations.

Egoistic, altruistic, and biospheric environmental concerns: a path analytic investigation of their determinants.

PubMed

Swami, Viren; Chamorro-Premuzic, Tomas; Snelgar, Rosemary; Furnham, Adrian

2010-04-01

Previous studies have shown that environmental concerns (ECs) can be reduced to a three-factor model - comprising altruistic, biospheric, and egoistic concerns - but there have been few studies examining individual difference predictors of ECs. In this study with 203 individuals from a British community sample, we show that biospheric concern was significantly associated with participants' age, political orientation, Machiavellianism, and the Big Five personality traits of Agreeableness, Emotional Stability, and Conscientiousness. Altruistic concern was significantly associated with sex, age, political orientation, and Machiavellianism, but not the Big Five traits, whereas egoistic concern was not significantly associated with any of these predictors except sex. These results are discussed in relation to previous work on ECs and pro-environmental behavior.

Constraining ecosystem processes from tower fluxes and atmospheric profiles.

PubMed

Hill, T C; Williams, M; Woodward, F I; Moncrieff, J B

2011-07-01

The planetary boundary layer (PBL) provides an important link between the scales and processes resolved by global atmospheric sampling/modeling and site-based flux measurements. The PBL is in direct contact with the land surface, both driving and responding to ecosystem processes. Measurements within the PBL (e.g., by radiosondes, aircraft profiles, and flask measurements) have a footprint, and thus an integrating scale, on the order of 1-100 km. We use the coupled atmosphere-biosphere model (CAB) and a Bayesian data assimilation framework to investigate the amount of biosphere process information that can be inferred from PBL measurements. We investigate the information content of PBL measurements in a two-stage study. First, we demonstrate consistency between the coupled model (CAB) and measurements, by comparing the model to eddy covariance flux tower measurements (i.e., water and carbon fluxes) and also PBL scalar profile measurements (i.e., water, carbon dioxide, and temperature) from Canadian boreal forest. Second, we use the CAB model in a set of Bayesian inversions experiments using synthetic data for a single day. In the synthetic experiment, leaf area and respiration were relatively well constrained, whereas surface albedo and plant hydraulic conductance were only moderately constrained. Finally, the abilities of the PBL profiles and the eddy covariance data to constrain the parameters were largely similar and only slightly lower than the combination of both observations.

Simple global carbon model: The atmosphere-terrestrial biosphere-ocean interaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwon, O.Y.; Schnoor, J.L.

A simple global carbon model has been developed for scenario analysis, and research needs prioritization. CO{sub 2} fertilization and temperature effects are included in the terrestrial biosphere compartment, and the ocean compartment includes inorganic chemistry which, with ocean water circulation, enables the calculation of time-variable oceanic carbon uptake. Model-derived Q{sub 10} values (the increasing rate for every 10{degrees}C increase of temperature) are 1.37 for land biota photosynthesis, 1.89 for land biota respiration, and 1.95 for soil respiration, and feedback temperature is set at 0.01{degrees}C/ppm of CO{sub 2}. These could be the important parameters controlling the carbon cycle in potential globalmore » warming scenarios. Scenario analysis, together with sensitivity analysis of temperature feedback, suggests that if CO{sub 2} emissions from fossil fuel combustion continue at the present increasing rate of {approximately}1.5% per year, a CO{sub 2} doubling (to 560 ppm) will appear in year 2060. Global warming would be responsible for 40 Gt as carbon (Gt C) accumulation in the land biota, 88 Gt C depletion from the soil carbon, a 7 Gt C accumulation in the oceans, and a 19 ppm increase in atmospheric CO{sub 2}. The ocean buffering capacity to take up the excess CO{sub 2} will decrease with the increasing atmospheric CO{sub 2} concentration. 51 refs., 8 figs., 3 tabs.« less

Terrestrial biosphere models underestimate photosynthetic capacity and CO2 assimilation in the Arctic.

PubMed

Rogers, Alistair; Serbin, Shawn P; Ely, Kim S; Sloan, Victoria L; Wullschleger, Stan D

2017-12-01

Terrestrial biosphere models (TBMs) are highly sensitive to model representation of photosynthesis, in particular the parameters maximum carboxylation rate and maximum electron transport rate at 25°C (V c,max.25 and J max.25 , respectively). Many TBMs do not include representation of Arctic plants, and those that do rely on understanding and parameterization from temperate species. We measured photosynthetic CO 2 response curves and leaf nitrogen (N) content in species representing the dominant vascular plant functional types found on the coastal tundra near Barrow, Alaska. The activation energies associated with the temperature response functions of V c,max and J max were 17% lower than commonly used values. When scaled to 25°C, V c,max.25 and J max.25 were two- to five-fold higher than the values used to parameterize current TBMs. This high photosynthetic capacity was attributable to a high leaf N content and the high fraction of N invested in Rubisco. Leaf-level modeling demonstrated that current parameterization of TBMs resulted in a two-fold underestimation of the capacity for leaf-level CO 2 assimilation in Arctic vegetation. This study highlights the poor representation of Arctic photosynthesis in TBMs, and provides the critical data necessary to improve our ability to project the response of the Arctic to global environmental change. No claim to original US Government works. New Phytologist © 2017 New Phytologist Trust.

Terrestrial biosphere models underestimate photosynthetic capacity and CO 2 assimilation in the Arctic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rogers, Alistair; Serbin, Shawn P.; Ely, Kim S.

Terrestrial biosphere models (TBMs) are highly sensitive to model representation of photosynthesis, in particular the parameters maximum carboxylation rate and maximum electron transport rate at 25°C (V c,max.25 and J max.25, respectively). Many TBMs do not include representation of Arctic plants, and those that do rely on understanding and parameterization from temperate species. We then measured photosynthetic CO 2 response curves and leaf nitrogen (N) content in species representing the dominant vascular plant functional types found on the coastal tundra near Barrow, Alaska. The activation energies associated with the temperature response functions of Vc,max and Jmax were 17% lower thanmore » commonly used values. When scaled to 25°C, Vc,max.25 and J max.25 were two- to five-fold higher than the values used to parameterize current TBMs. This high photosynthetic capacity was attributable to a high leaf N content and the high fraction of N invested in Rubisco. Leaf-level modeling demonstrated that current parameterization of TBMs resulted in a two-fold underestimation of the capacity for leaf-level CO 2 assimilation in Arctic vegetation. Our study highlights the poor representation of Arctic photosynthesis in TBMs, and provides the critical data necessary to improve our ability to project the response of the Arctic to global environmental change.« less

Terrestrial biosphere models underestimate photosynthetic capacity and CO 2 assimilation in the Arctic

DOE PAGES

Rogers, Alistair; Serbin, Shawn P.; Ely, Kim S.; ...

2017-09-06

Terrestrial biosphere models (TBMs) are highly sensitive to model representation of photosynthesis, in particular the parameters maximum carboxylation rate and maximum electron transport rate at 25°C (V c,max.25 and J max.25, respectively). Many TBMs do not include representation of Arctic plants, and those that do rely on understanding and parameterization from temperate species. We then measured photosynthetic CO 2 response curves and leaf nitrogen (N) content in species representing the dominant vascular plant functional types found on the coastal tundra near Barrow, Alaska. The activation energies associated with the temperature response functions of Vc,max and Jmax were 17% lower thanmore » commonly used values. When scaled to 25°C, Vc,max.25 and J max.25 were two- to five-fold higher than the values used to parameterize current TBMs. This high photosynthetic capacity was attributable to a high leaf N content and the high fraction of N invested in Rubisco. Leaf-level modeling demonstrated that current parameterization of TBMs resulted in a two-fold underestimation of the capacity for leaf-level CO 2 assimilation in Arctic vegetation. Our study highlights the poor representation of Arctic photosynthesis in TBMs, and provides the critical data necessary to improve our ability to project the response of the Arctic to global environmental change.« less

Palaeoecological data as a tool to predict possible future vegetation changes in the boreal forest zone of European Russia: a case study from the Central Forest Biosphere Reserve

NASA Astrophysics Data System (ADS)

Novenko, E. Yu; Tsyganov, A. N.; Olchev, A. V.

2018-01-01

New multi-proxy records (pollen, testate amoebae, and charcoal) were applied to reconstruct the vegetation dynamics in the boreal forest area of the southern part of Valdai Hills (the Central Forest Biosphere Reserve) during the Holocene. The reconstructions of the mean annual temperature and precipitation, the climate moisture index (CMI), peatland surface moisture, and fire activity have shown that climate change has a significant impact on the boreal forests of European Russia. Temperature growth and decreased moistening during the warmest phases of the Holocene Thermal Maximum in 7.0-6.2 ka BP and 6.0-5.5 ka BP and in the relatively warm phase in 3.4-2.5 ka BP led to structural changes in plant communities, specifically an increase in the abundance of broadleaf tree species in forest stands and the suppression of Picea. The frequency of forest fires was higher in that period, and it resulted in the replacement of spruce forests by secondary stands with Betula and Pinus. Despite significant changes in the climatic parameters projected for the 21st century using even the optimistic RCP2.6 scenario, the time lag between climate changes and vegetation responses makes any catastrophic vegetation disturbances (due to natural reasons) in the area in the 21st century unlikely.

Environmental gradients regulate the spatio-temporal variability of phytoplankton assemblages in the Can Gio Mangrove Biosphere Reserve, Vietnam

NASA Astrophysics Data System (ADS)

Pham, Thanh-Luu

2017-12-01

This paper covers spatial and temporal variation in phytoplankton communities and physico-chemical variables in the Can Gio Mangrove Biosphere Reserve (CGMBR), Vietnam, based on field measurement conducted monthly at nine stations during February 2009 to January 2010. Species diversity, richness and phytoplankton abundance were calculated. Canonical Correspondence Analysis (CCA) was used to investigate the relationship between environmental factors and phytoplankton community. A total of 126 species were recorded with a clear dominance of Bacillariophyceae, which formed about 76.4% of the total phytoplankton counts with an annual average of 44.900 cells/L. Other algal classes like Dinophyceae, Cyanophyceae and Chrysophyceae sustained low counts, forming collectively about 14% of the total abundance of phytoplankton. Although Chaetoceros and Coscinodiscus were the most dominant genera, Schroederella and Skeletonema showed high abundance during the studied period. Among the nine environmental parameters tested in this study, salinity, nitrate and ammonium were found to be significantly different between two seasons. On the other hand, no significant difference was found between stations for the studied variables. Results of CCA indicated that phytoplankton assemblage in the CGMBR was influenced by salinity, nitrate and phosphate concentration. This is the first study simultaneously investigating the phytoplankton communities and their environment in this area and it is essential in order to set up the baseline of future studies.

Extending amulti-scale parameter regionalization (MPR) method by introducing parameter constrained optimization and flexible transfer functions

NASA Astrophysics Data System (ADS)

Klotz, Daniel; Herrnegger, Mathew; Schulz, Karsten

2015-04-01

A multi-scale parameter-estimation method, as presented by Samaniego et al. (2010), is implemented and extended for the conceptual hydrological model COSERO. COSERO is a HBV-type model that is specialized for alpine-environments, but has been applied over a wide range of basins all over the world (see: Kling et al., 2014 for an overview). Within the methodology available small-scale information (DEM, soil texture, land cover, etc.) is used to estimate the coarse-scale model parameters by applying a set of transfer-functions (TFs) and subsequent averaging methods, whereby only TF hyper-parameters are optimized against available observations (e.g. runoff data). The parameter regionalisation approach was extended in order to allow for a more meta-heuristical handling of the transfer-functions. The two main novelties are: 1. An explicit introduction of constrains into parameter estimation scheme: The constraint scheme replaces invalid parts of the transfer-function-solution space with valid solutions. It is inspired by applications in evolutionary algorithms and related to the combination of learning and evolution. This allows the consideration of physical and numerical constraints as well as the incorporation of a priori modeller-experience into the parameter estimation. 2. Spline-based transfer-functions: Spline-based functions enable arbitrary forms of transfer-functions: This is of importance since in many cases the general relationship between sub-grid information and parameters are known, but not the form of the transfer-function itself. The contribution presents the results and experiences with the adopted method and the introduced extensions. Simulation are performed for the pre-alpine/alpine Traisen catchment in Lower Austria. References: Samaniego, L., Kumar, R., Attinger, S. (2010): Multiscale parameter regionalization of a grid-based hydrologic model at the mesoscale, Water Resour. Res., doi: 10.1029/2008WR007327 Kling, H., Stanzel, P., Fuchs, M., and Nachtnebel, H. P. (2014): Performance of the COSERO precipitation-runoff model under non-stationary conditions in basins with different climates, Hydrolog. Sci. J., doi: 10.1080/02626667.2014.959956.

Stability analysis on the flow and heat transfer of nanofluid past a stretching/shrinking cylinder with suction effect

NASA Astrophysics Data System (ADS)

Bakar, Nor Ashikin Abu; Bachok, Norfifah; Arifin, Norihan Md.; Pop, Ioan

2018-06-01

The steady boundary layer flow over a stretching/shrinking cylinder with suction effect is numerically studied. Using a similarity transformations, the governing partial differential equations are transformed into a set of nonlinear differential equations and have been solved numerically using a bvp4c code in Matlab software. The nanofluid model used is taking into account the effects of Brownian motion and thermophoresis. The influences of the governing parameters namely the curvature parameter γ, mass suction parameter S, Brownian motion parameter Nb and thermophoresis parameter Nt on the flow, heat and mass transfers characteristics are presented graphically. The numerical results obtained for the skin friction coefficient, local Nusselt number and local Sherwood number are thoroughly determined and presented graphically for several values of the governing parameters. From our investigation, it is found that the non-unique (dual) solutions exist for a certain range of mass suction parameter. It is observed that as curvature parameter increases, the skin friction coefficient and heat transfer rate decrease, meanwhile the mass transfer rates increase. Moreover, the stability analysis showed that the first solution is linearly stable, while the second solution is linearly unstable.

Determination of the diffusion coefficient and phase-transfer rate parameter in LaNi{sub 5} and MmNi{sub 3.6}Co{sub 0.8}Mn{sub 0.4}Al{sub 0.3} using microelectrodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lundqvist, A.; Lindbergh, G.

1998-11-01

A potential-step method for determining the diffusion coefficient and phase-transfer parameter in metal hydrides by using microelectrodes was investigated. It was shown that a large potential step is not enough to ensure a completely diffusion-limited mass transfer if a surface-phase transfer reaction takes place at a finite rate. It was shown, using a kinetic expression for the surface phase-transfer reaction, that the slope of the logarithm of the current vs. time curve will be constant both in the case of the mass-transfer limited by diffusion or by diffusion and a surface-phase transfer. The diffusion coefficient and phase-transfer rate parameter weremore » accurately determined for MmNi{sub 3.6}Co{sub 0.8}Mn{sub 0.4}Al{sub 0.3} using a fit to the whole transient. The diffusion coefficient was found to be (1.3 {+-} 0.3) {times} 10{sup {minus}13} m{sup 2}/s. The fit was good and showed that a pure diffusion model was not enough to explain the observed transient. The diffusion coefficient and phase-transfer rate parameter were also estimated for pure LaNi{sub 5}. A fit of the whole curve showed that neither a pure diffusion model nor a model including phase transfer could explain the whole transient.« less

Solar irradiance changes and photobiological effects at earth's surface following astrophysical ionizing radiation events.

PubMed

Thomas, Brian C; Neale, Patrick J; Snyder, Brock R

2015-03-01

Astrophysical ionizing radiation events have been recognized as a potential threat to life on Earth, primarily through depletion of stratospheric ozone and subsequent increase in surface-level solar ultraviolet radiation. Simulations of the atmospheric effects of a variety of events (such as supernovae, gamma-ray bursts, and solar proton events) have been previously published, along with estimates of biological damage at Earth's surface. In this work, we employed the Tropospheric Ultraviolet and Visible (TUV) radiative transfer model to expand and improve calculations of surface-level irradiance and biological impacts following an ionizing radiation event. We considered changes in surface-level UVB, UVA, and photosynthetically active radiation (visible light) for clear-sky conditions and fixed aerosol parameter values. We also considered a wide range of biological effects on organisms ranging from humans to phytoplankton. We found that past work overestimated UVB irradiance but that relative estimates for increase in exposure to DNA-damaging radiation are still similar to our improved calculations. We also found that the intensity of biologically damaging radiation varies widely with organism and specific impact considered; these results have implications for biosphere-level damage following astrophysical ionizing radiation events. When considering changes in surface-level visible light irradiance, we found that, contrary to previous assumptions, a decrease in irradiance is only present for a short time in very limited geographical areas; instead we found a net increase for most of the modeled time-space region. This result has implications for proposed climate changes associated with ionizing radiation events.

Numerical studies of convective heat transfer in an inclined semiannular enclosure

NASA Technical Reports Server (NTRS)

Wang, Lin-Wen; Yung, Chain-Nan; Chai, An-Ti; Rashidnia, Nasser

1989-01-01

Natural convection heat transfer in a two-dimensional differentially heated semiannular enclosure is studied. The enclosure is isothermally heated and cooled at the inner and outer walls, respectively. A commercial software based on the SIMPLER algorithm was used to simulate the velocity and temperature profiles. Various parameters that affect the momentum and heat transfer processes were examined. These parameters include the Rayleigh number, Prandtl number, radius ratio, and the angle of inclination. A flow regime extending from conduction-dominated to convection-dominated flow was examined. The computed results of heat transfer are presented as a function of flow parameter and geometric factors. It is found that the heat transfer rate attains a minimum when the enclosure is tilted about +50 deg with respect to the gravitational direction.

Publications of the biospheric research program: 1981-1987

NASA Technical Reports Server (NTRS)

Wallace, Janice S. (Editor)

1988-01-01

Presented is a list of publications of investigators supported by the Biospheric Research Program of the Biological Systems Research Branch, Life Sciences Division, and the Office of Space Science and Applications. It includes publications dated as of December 31, 1987 and entered into the Life Sciences Bibliographic Database at the George Washington University. Publications are organized by the year published.

"Biosphere Reserve"--The Actual Research Subject of the Sustainable Development Process"

ERIC Educational Resources Information Center

Khasaev, Gabibulla R.; Sadovenko, Marina Yu.; Isaev, Roman O.

2016-01-01

The relevance of the analyzed issue is caused by the growing slippage of research funds of sustainable development in its practice. The purpose of the article is the theoretical basis of the biosphere reserve as a scientific research subject that is relevant to rules of the scientific activity. The leading approach to the study of this issue is…

Bird checklist, Guánica Biosphere Reserve, Puerto Rico

Treesearch

Wayne J. Arendt; John Faaborg; Miguel Canals; Jerry Bauer

2015-01-01

This research note compiles 43 years of research and monitoring data to produce the first comprehensive checklist of the dry forest avian community found within the Guánica Biosphere Reserve. We provide an overview of the reserve along with sighting locales, a list of 185 birds with their resident status and abundance, and a list of the available bird habitats....

Monitoring recreational impacts in wilderness of Kamchatka (on example of Kronotsky State Natural Biosphere Preserve)

Treesearch

Anya V. Zavadskaya

2011-01-01

This paper describes an assessment and monitoring program that was designed and initiated for monitoring recreational impacts in a wilderness in Kamchatka. The framework of the recreational assessment was tested through its application to a case study conducted during the summers of 2008 and 2009 in the Kronotsky State Natural Biosphere Preserve (Kamchatka peninsula,...

Understanding the Relationship between Christian Orthodoxy and Environmentalism : The Mediating Role of Perceived Environmental Consequences

ERIC Educational Resources Information Center

Truelove, Heather Barnes; Joireman, Jeff

2009-01-01

The present study evaluated the hypothesis that people who strongly adhere to Christian orthodoxy may be less proenvironmental to the extent that they are less aware of the biospheric consequences of environmental problems (biospheric AC) but that they may be more proenvironmental than others to the extent that they are more aware of the egoistic…

Astrobiology: Life on Earth (and Elsewhere?)

NASA Technical Reports Server (NTRS)

Des Marais, David J.

2016-01-01

Astrobiology investigates the origins, evolution and distribution of life in the universe. Scientists study how stellar systems and their planets can create planetary environments that sustain biospheres. They search for biosignatures, which are objects, substances and or patterns that indicate the presence of life. Studies of Earth's early biosphere enhance these search strategies and also provide key insights about our own origins.

Searching for Life Underground: An Analysis of Remote Sensing Observations of a Drill Core from Rio Tinto, Spain for Mineralogical Indications of Biological Activity

NASA Technical Reports Server (NTRS)

Battler, M.; Stoker, C.

2005-01-01

Water is unstable on the surface of Mars, and therefore the Martian surface is not likely to support life. It is possible, however, that liquid water exists beneath the surface of Mars, and thus life might also be found in the subsurface. Subsurface life would most likely be microbial, anaerobic, and chemoautotrophic; these types of biospheres on Earth are rare, and not well understood. Finding water and life are high priorities for Mars exploration, and therefore it is important that we learn to explore the subsurface robotically, by drilling. The Mars Analog Rio Tinto Experiment (MARTE), has searched successfully for a subsurface biosphere at Rio Tinto, Spain [1,2,3,4]. The Rio Tinto study site was selected to search for a subsurface biosphere because the extremely low pH and high concentrations of elements such as iron and copper in the Tinto River suggest the presence of a chemoautotrophic biosphere in the subsurface beneath the river. The Rio Tinto has been recognized as an important mineralogical analog to the Sinus Meridiani site on Mars [5].

Methane Production and Transport within the Marsh Biome of Biosphere 2

NASA Technical Reports Server (NTRS)

Molnar, Jennifer; Goodridge, Kelven

1997-01-01

In recent decades, the concentration of methane in the earth's atmosphere increased 1-2% annually. It's rate of increases, combined with methane's effectiveness as a greenhouse gas, has led to an intensive research effort to determine the sources and sinks of the gas in the environment. Biosphere 2 offers a unique opportunity to contribute to the effort because it lacks a major photochemical sink present in the Earth's atmosphere. Researchers can therefore concentrate on biological processes involved in methane cycles. Wetlands are a large source of atmospheric methane, due to anoxic conditions in the sediments and the abundance of organic materials. In order to determine if these conditions in Biosphere 2 also promote methane production, this study looked for the fluxes of methane and methods of transport of the gas from from the water and sediments to the atmosphere in the Marsh Biome. Fluxes of methane from the sediments and waters were measured using static chambers, peepers, and leaf bags. Fluxes and vertical profiles of methane in the sediments show that substantial amounts of methane are being produced in the marsh and are being transported into the Biosphere 2 environment.

The physics, biology, and environmental ethics of making mars habitable.

PubMed

McKay, C P; Marinova, M M

2001-01-01

The considerable evidence that Mars once had a wetter, more clement, environment motivates the search for past or present life on that planet. This evidence also suggests the possibility of restoring habitable conditions on Mars. While the total amounts of the key molecules--carbon dioxide, water, and nitrogen--needed for creating a biosphere on Mars are unknown, estimates suggest that there may be enough in the subsurface. Super greenhouse gases, in particular, perfluorocarbons, are currently the most effective and practical way to warm Mars and thicken its atmosphere so that liquid water is stable on the surface. This process could take approximately 100 years. If enough carbon dioxide is frozen in the South Polar Cap and absorbed in the regolith, the resulting thick and warm carbon dioxide atmosphere could support many types of microorganisms, plants, and invertebrates. If a planet-wide martian biosphere converted carbon dioxide into oxygen with an average efficiency equal to that for Earth's biosphere, it would take > 100,000 years to create Earth-like oxygen levels. Ethical issues associated with bringing life to Mars center on the possibility of indigenous martian life and the relative value of a planet with or without a global biosphere.

Biochemical and physiological bases for the use of carbon and nitrogen isotopes in environmental and ecological studies

NASA Astrophysics Data System (ADS)

Ohkouchi, Naohiko; Ogawa, Nanako O.; Chikaraishi, Yoshito; Tanaka, Hiroyuki; Wada, Eitaro

2015-12-01

We review the biochemical and physiological bases of the use of carbon and nitrogen isotopic compositions as an approach for environmental and ecological studies. Biochemical processes commonly observed in the biosphere, including the decarboxylation and deamination of amino acids, are the key factors in this isotopic approach. The principles drawn from the isotopic distributions disentangle the complex dynamics of the biosphere and allow the interactions between the geosphere and biosphere to be analyzed in detail. We also summarize two recently examined topics with new datasets: the isotopic compositions of individual biosynthetic products (chlorophylls and amino acids) and those of animal organs for further pursuing the basis of the methodology. As a tool for investigating complex systems, compound-specific isotopic analysis compensates the intrinsic disadvantages of bulk isotopic signatures. Chlorophylls provide information about the particular processes of various photoautotrophs, whereas amino acids provide a precise measure of the trophic positions of heterotrophs. The isotopic distributions of carbon and nitrogen in a single organism as well as in the whole biosphere are strongly regulated, so that their major components such as amino acids are coordinated appropriately rather than controlled separately.

The physics, biology, and environmental ethics of making mars habitable

NASA Technical Reports Server (NTRS)

McKay, C. P.; Marinova, M. M.

2001-01-01

The considerable evidence that Mars once had a wetter, more clement, environment motivates the search for past or present life on that planet. This evidence also suggests the possibility of restoring habitable conditions on Mars. While the total amounts of the key molecules--carbon dioxide, water, and nitrogen--needed for creating a biosphere on Mars are unknown, estimates suggest that there may be enough in the subsurface. Super greenhouse gases, in particular, perfluorocarbons, are currently the most effective and practical way to warm Mars and thicken its atmosphere so that liquid water is stable on the surface. This process could take approximately 100 years. If enough carbon dioxide is frozen in the South Polar Cap and absorbed in the regolith, the resulting thick and warm carbon dioxide atmosphere could support many types of microorganisms, plants, and invertebrates. If a planet-wide martian biosphere converted carbon dioxide into oxygen with an average efficiency equal to that for Earth's biosphere, it would take > 100,000 years to create Earth-like oxygen levels. Ethical issues associated with bringing life to Mars center on the possibility of indigenous martian life and the relative value of a planet with or without a global biosphere.

Deciduous birch canopy as unexpected contributor to stand level atmospheric reactivity in boreal forests

NASA Astrophysics Data System (ADS)

Bäck, Jaana; Taipale, Ditte; Aalto, Juho

2017-04-01

In boreal forests, deciduous trees such as birches may in future climate become more abundant due to their large biomass production capacity, relatively good resource use ability and large acclimation potential to elevated CO2 levels and warmer climate. Increase in birch abundance may lead to unpredicted consequences in atmospheric composition. Currently it is acknowledged that conifers such as Scots pine and Norway spruce are important sources for volatile organic compounds (VOCs), especially monoterpenes, throughout the year, although the strong temperature relationships implies that emissions are highest in summertime. However, the dynamics of the deciduous birch foliage VOC emissions and their relationship with environmental drivers during the development, maturation and senescence of foliage has not been well analyzed. Long-term measurements of birch, which are unfortunately very sparse, can provide very useful information for the development of biosphere-atmosphere models that simulate boreal and subarctic forested areas where birch is often a sub-canopy species, occurs as a mixture among conifers or forms even pure stands in the higher latitudes. We measured the branch level VOC emissions from a mature Silver birch with proton transfer reaction mass spectrometer during 2014 and 2015 at the SMEAR II station (Station for Measuring Ecosystem-Atmosphere Relations), southern Finland. Our results showed that the Silver birch foliage is a huge source for both short-chained volatiles such as methanol, acetaldehyde and acetone, as well as for monoterpenes. The mean emission rates from birch leaves were 5 to 10 times higher than the corresponding emissions from Scots pine shoots. We compared several semi-empirical model approaches for determining the birch foliage monoterpene standardized emission potentials, and utilized the continuous emission measurements from the two growing seasons for development of a novel algorithm which accounts for the leaf development and senescence in addition to prevailing temperature and light conditions. With these improvements and inputs to the 1D biosphere-atmosphere model SOSAA (model to Simulate Organic vapours, Sulphuric Acid and Aerosols), we showed that the contribution of Silver birch to stand scale atmospheric reactivity may exceed the ones from conifers, and therefore specific land use and species distribution patterns should be accounted for in biosphere-atmosphere models describing the surface-atmosphere exchange of reactive gases.

Terraforming planet Dune: Climate-vegetation interactions on a sandy planet

NASA Astrophysics Data System (ADS)

Cresto Aleina, F.; Baudena, M.; D'Andrea, F.; Provenzale, A.

2012-04-01

The climate and the biosphere of planet Earth interact in multiple, complicated ways and on many spatial and temporal scales. Some of these processes can be studied with the help of simple mathematical models, as done for the effects of vegetation on albedo in desert areas and for the mechanisms by which terrestrial vegetation affects water fluxes in arid environments. Conceptual models of this kind do not attempt at providing quantitative descriptions of the climate-biosphere interaction, but rather to explore avenues and mechanisms which can play a role in the real system, providing inspiration for further research. In this work, we develop a simple conceptual box model in the spirit illustrated above, to explore whether and how vegetation affects the planetary hydrologic cycle. We imagine a planet with no oceans and whose surface is entirely covered with sand, quite similar to planet Dune of the science-fiction series by Frank Herbert (1965). We suppose that water is entirely in the sand, below the surface. Without vegetation, only evaporation takes place, affecting the upper sand layer for a maximum depth of a few cm. The amount of water that is evaporated in the atmosphere is relatively small, and not sufficient to trigger a full hydrologic cycle. The question is what happens to this planet when vegetation is introduced: the root depth can reach a meter or more, and plant transpiration can then transfer a much larger amount of water to the atmosphere. One may wonder whether the presence of vegetation is sufficient to trigger a hydrologic cycle with enough precipitation to sustain the vegetation itself and, if the answer is positive, what is the minimum vegetation cover that is required to maintain the cycle active. In more precise terms, we want to know whether the introduction of vegetation and of the evapotranspiration feedback allows for the existence of multiple equilibria (or solutions) in the soil-vegetation-atmosphere system. Although the box model introduced here is best formulated in terms of a hypothetical sandy planet, the results can be used to study the hydrologic cycle on wide continental regions of the Earth. On the other hand, our findings show how the definition of a habitable climate may also depend on surface characteristics, and in particular on biosphere and climate interactions.

Cytonuclear genetics of experimental fish hybrid zones inside Biosphere 2

USGS Publications Warehouse

Scribner, K.T.; Avise, John C.

1994-01-01

Two species of mosquitofish (family Poeciliidae) known to hybridize in nature were introduced into freshwater habitats inside Biosphere 2, and their population genetics were monitored after 2 years. Within four to six generations, nuclear and cytoplasmic markers characteristic of Gambusia holbrooki had risen greatly in frequency, although some Gambusia affinis alleles and haplotypes were retained primarily in recombinant genotypes, indicative of introgressive hybridization. The temporal cytonuclear dynamics proved similar to population genetic changes observed in replicated experimental hybrid populations outside of Biosphere 2, thus indicating strong directional selection favoring G. holbrooki genotypes across the range of environments monitored. When interpreted in the context of species-specific population demographies observed previously, results suggest that the extremely rapid evolution in these zones of secondary contact is attributable primarily to species differences in life-history traits.

Information in the Biosphere: Biological and Digital Worlds.

PubMed

Gillings, Michael R; Hilbert, Martin; Kemp, Darrell J

2016-03-01

Evolution has transformed life through key innovations in information storage and replication, including RNA, DNA, multicellularity, and culture and language. We argue that the carbon-based biosphere has generated a cognitive system (humans) capable of creating technology that will result in a comparable evolutionary transition. Digital information has reached a similar magnitude to information in the biosphere. It increases exponentially, exhibits high-fidelity replication, evolves through differential fitness, is expressed through artificial intelligence (AI), and has facility for virtually limitless recombination. Like previous evolutionary transitions, the potential symbiosis between biological and digital information will reach a critical point where these codes could compete via natural selection. Alternatively, this fusion could create a higher-level superorganism employing a low-conflict division of labor in performing informational tasks. Copyright © 2015 Elsevier Ltd. All rights reserved.

Data management at Biosphere 2 center

NASA Technical Reports Server (NTRS)

McCreary, Leone F.

1997-01-01

Throughout the history of Biosphere 2, the collecting and recording of biological data has been sporadic. Currently no active effort to administer and record regular biological surveys is being made. Also, there is no central location, such as an on-site data library, where all records from various studies have been archived. As a research institute, good, complete data records are at the core of all Biosphere 2's scientific endeavors. It is therefore imperative that an effective data management system be implemented within the management and research departments as soon as possible. Establishing this system would require three general phases: (1) Design/implement a new archiving/management program (including storage, cataloging and retrieval systems); (2) Organize and input baseline and intermediate data from existing archives; and (3) Maintain records by inputting new data.

Deuterobiosphere the chemosynthetic second biosphere of the globe. A first review.

PubMed

Por, Francis D

2008-06-01

With the discovery of Ophel, a chemosynthesis-based continental subterranean environment (Por 2007), it became evident that such environments, previously known only from the sea, are spanning the world as a parallel biosphere, the deuterobiosphere. In this preliminary contribution the different known biomes of the deuterobiosphere are reviewed and some general and comparative features are listed. © 2008 ISZS, Blackwell Publishing and IOZ/CAS.

Biodiversity conservation, sustainable development, and the U.S. Man and the Biosphere Program: Past contributions and future directions

Treesearch

P. N. Manley; D. C. Hayes

2006-01-01

U.S. Man and the Biosphere (MAB) Program is part of the United Nations Educational, Scientific, and Cultural Organization (UNESCO) MAB program, and is one of six regional MAB programs that span the globe. The MAB Program was created in 1971 with the goal to explore, demonstrate, promote, and encourage harmonious relationships between people and their environments....

Stream denitrification across biomes and its response to anthropogenic nitrate loading

Treesearch

Patrick J. Mulholland; Ashley M. Helton; Geoffrey C. Poole; Robert O. Hall; Stephen K. Hamilton; et al

2008-01-01

Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing1, 2 and terrestrial ecosystems are becoming increasingly nitrogen-saturated3, causing more bioavailable nitrogen to enter groundwater and surface waters4, 5, 6. Large-scale nitrogen budgets show that an average of about 20–25 per cent of the nitrogen added to the biosphere is exported from...

Land-related global habitability science issues

NASA Technical Reports Server (NTRS)

1983-01-01

The scientific investigation of the viewpoint of the biosphere that living organisms and their physical and chemical environment are bound, inseparable parts of one set of closely coupled global processes of the global biogeochemical system, life and life support cycles, is discussed as one of the major scientific challenges of the next decade by building from understanding land processes to interdisciplinary, holistic studies of biospheric dynamics including human impacts.

SeaWiFS Third Anniversary Global Biosphere

NASA Technical Reports Server (NTRS)

2002-01-01

September 18,2000 is the third anniversary of the start of regular SeaWiFS operations of this remarkable planet called Earth. This SeaWiFS image is of the Global Biosphere depicting the ocean's long-term average phytoplankton chlorophyll concentration acquired between September 1997 and August 2000 combined with the SeaWiFS-derived Normalized Difference Vegetation Index (NDVI) over land during July 2000.

Transfer Function Identification Using Orthogonal Fourier Transform Modeling Functions

NASA Technical Reports Server (NTRS)

Morelli, Eugene A.

2013-01-01

A method for transfer function identification, including both model structure determination and parameter estimation, was developed and demonstrated. The approach uses orthogonal modeling functions generated from frequency domain data obtained by Fourier transformation of time series data. The method was applied to simulation data to identify continuous-time transfer function models and unsteady aerodynamic models. Model fit error, estimated model parameters, and the associated uncertainties were used to show the effectiveness of the method for identifying accurate transfer function models from noisy data.

Towards a representation of priming on soil carbon decomposition in the global land biosphere model ORCHIDEE (version 1.9.5.2)

NASA Astrophysics Data System (ADS)

Guenet, Bertrand; Esteban Moyano, Fernando; Peylin, Philippe; Ciais, Philippe; Janssens, Ivan A.

2016-03-01

Priming of soil carbon decomposition encompasses different processes through which the decomposition of native (already present) soil organic matter is amplified through the addition of new organic matter, with new inputs typically being more labile than the native soil organic matter. Evidence for priming comes from laboratory and field experiments, but to date there is no estimate of its impact at global scale and under the current anthropogenic perturbation of the carbon cycle. Current soil carbon decomposition models do not include priming mechanisms, thereby introducing uncertainty when extrapolating short-term local observations to ecosystem and regional to global scale. In this study we present a simple conceptual model of decomposition priming, called PRIM, able to reproduce laboratory (incubation) and field (litter manipulation) priming experiments. Parameters for this model were first optimized against data from 20 soil incubation experiments using a Bayesian framework. The optimized parameter values were evaluated against another set of soil incubation data independent from the ones used for calibration and the PRIM model reproduced the soil incubations data better than the original, CENTURY-type soil decomposition model, whose decomposition equations are based only on first-order kinetics. We then compared the PRIM model and the standard first-order decay model incorporated into the global land biosphere model ORCHIDEE (Organising Carbon and Hydrology In Dynamic Ecosystems). A test of both models was performed at ecosystem scale using litter manipulation experiments from five sites. Although both versions were equally able to reproduce observed decay rates of litter, only ORCHIDEE-PRIM could simulate the observed priming (R2 = 0.54) in cases where litter was added or removed. This result suggests that a conceptually simple and numerically tractable representation of priming adapted to global models is able to capture the sign and magnitude of the priming of litter and soil organic matter.

Towards a representation of priming on soil carbon decomposition in the global land biosphere model ORCHIDEE (version 1.9.5.2)

NASA Astrophysics Data System (ADS)

Guenet, B.; Moyano, F. E.; Peylin, P.; Ciais, P.; Janssens, I. A.

2015-10-01

Priming of soil carbon decomposition encompasses different processes through which the decomposition of native (already present) soil organic matter is amplified through the addition of new organic matter, with new inputs typically being more labile than the native soil organic matter. Evidence for priming comes from laboratory and field experiments, but to date there is no estimate of its impact at global scale and under the current anthropogenic perturbation of the carbon cycle. Current soil carbon decomposition models do not include priming mechanisms, thereby introducing uncertainty when extrapolating short-term local observations to ecosystem and regional to global scale. In this study we present a simple conceptual model of decomposition priming, called PRIM, able to reproduce laboratory (incubation) and field (litter manipulation) priming experiments. Parameters for this model were first optimized against data from 20 soil incubation experiments using a Bayesian framework. The optimized parameter values were evaluated against another set of soil incubation data independent from the ones used for calibration and the PRIM model reproduced the soil incubations data better than the original, CENTURY-type soil decomposition model, whose decomposition equations are based only on first order kinetics. We then compared the PRIM model and the standard first order decay model incorporated into the global land biosphere model ORCHIDEE. A test of both models was performed at ecosystem scale using litter manipulation experiments from 5 sites. Although both versions were equally able to reproduce observed decay rates of litter, only ORCHIDEE-PRIM could simulate the observed priming (R2 = 0.54) in cases where litter was added or removed. This result suggests that a conceptually simple and numerically tractable representation of priming adapted to global models is able to capture the sign and magnitude of the priming of litter and soil organic matter.

D:L-AMINO Acids and the Turnover of Microbial Biomass

NASA Astrophysics Data System (ADS)

Lomstein, B. A.; Braun, S.; Mhatre, S. S.; Jørgensen, B. B.

2015-12-01

Decades of ocean drilling have demonstrated wide spread microbial life in deep sub-seafloor sediment, and surprisingly high microbial cell numbers. Despite the ubiquity of life in the deep biosphere, the large community sizes and the low energy fluxes in the vast buried ecosystem are still poorly understood. It is not know whether organisms of the deep biosphere are specifically adapted to extremely low energy fluxes or whether most of the observed cells are in a maintenance state. Recently we developed and applied a new culture independent approach - the D:L-amino acid model - to quantify the turnover times of living microbial biomass, microbial necromass and mean metabolic rates. This approach is based on the built-in molecular clock in amino acids that very slowly undergo chemical racemization until they reach an even mixture of L- and D- forms, unless microorganisms spend energy to keep them in the L-form that dominates in living organisms. The approach combines sensitive analyses of amino acids, the unique bacterial endospore marker (dipicolinic acid) with racemization dynamics of stereo-isomeric amino acids. Based on a heating experiment, we recently reported kinetic parameters for racemization of aspartic acid, glutamic acid, serine and alanine in bulk sediment from Aarhus Bay, Denmark. The obtained racemization rate constants were faster than the racemization rate constants of free amino acids, which we have previously applied in Holocene sediment from Aarhus Bay and in up to 10 mio yr old sediment from ODP Leg 201. Another important input parameter for the D:L-amino acid model is the cellular carbon content. It has recently been suggested that the cellular carbon content most likely is lower than previously thought. In recognition of these new findings, previously published data based on the D:L-amino acid model were recalculated and will be presented together with new data from an Arctic Holocene setting with constant sub-zero temperatures.

The roles of ecological first principles and evolutionary contingency in unraveling ecosystem response and reconstruction during the Permian-Triassic transition.

NASA Astrophysics Data System (ADS)

Roopnarine, P. D.; Weik, A.; Dineen, A.; Angielczyk, K.

2016-12-01

The Permian-Triassic mass extinction (PTME) is the most severe mass extinction recorded in Earth's history. Effects on the biosphere were complicated and often contradictory, e.g. selective species extinctions and exceptional species survival; prolonged miniaturization of some Early Triassic clades but rapid increases of size in others; and both simplified and complex trophic structures in various E. Triassic ecosystems. Here we present the results of a new generalized model of paleocommunity global stability (number of species capable of persistent coexistence in the absence of external perturbation), suggesting that community dynamics in response to species extinction, and the addition of new species in the aftermath of the PTME, is best understood as a complex outcome of predictable community dynamics and contingent, unpredictable evolutionary pathways. We applied the model to the best known PTME transitional terrestrial ecosystem, the Karoo Basin of South Africa. The model verifies previous claims that global stability scales negatively with increasing species richness and the strength of interspecific interactions. We also show that global stability scales negatively with intrinsic population growth rates. Taxon-rich Permian communities could therefore have persisted only under a restricted range of those parameters. Communities during three phases of the PTME, however, exhibited greater global stability than would be predicted from the pre-PTME communities. Those communities could therefore have maintained relative stabilities under a broader range of parameters, implying that species could have adapted by modifying life history and ecological traits with lesser negative consequences to community stability. The earliest post-PTME community with increased species richness, however, was less stable than would be predicted from pre-PTME communities. In both the extinction and aftermath communities, nonlinear deviations from the general scaling of stability result from structural features unique to those communities, perhaps limiting our ability to forecast biospheric responses to extreme perturbations.

FSW of Aluminum Tailor Welded Blanks across Machine Platforms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hovanski, Yuri; Upadhyay, Piyush; Carlson, Blair

2015-02-16

Development and characterization of friction stir welded aluminum tailor welded blanks was successfully carried out on three separate machine platforms. Each was a commercially available, gantry style, multi-axis machine designed specifically for friction stir welding. Weld parameters were developed to support high volume production of dissimilar thickness aluminum tailor welded blanks at speeds of 3 m/min and greater. Parameters originally developed on an ultra-high stiffness servo driven machine where first transferred to a high stiffness servo-hydraulic friction stir welding machine, and subsequently transferred to a purpose built machine designed to accommodate thin sheet aluminum welding. The inherent beam stiffness, bearingmore » compliance, and control system for each machine were distinctly unique, which posed specific challenges in transferring welding parameters across machine platforms. This work documents the challenges imposed by successfully transferring weld parameters from machine to machine, produced from different manufacturers and with unique control systems and interfaces.« less

Considering bioactivity in modelling continental growth and the Earth's evolution

NASA Astrophysics Data System (ADS)

Höning, D.; Spohn, T.

2013-09-01

The complexity of planetary evolution increases with the number of interacting reservoirs. On Earth, even the biosphere is speculated to interact with the interior. It has been argued (e.g., Rosing et al. 2006; Sleep et al, 2012) that the formation of continents could be a consequence of bioactivity harvesting solar energy through photosynthesis to help build the continents and that the mantle should carry a chemical biosignature. Through plate tectonics, the surface biosphere can impact deep subduction zone processes and the interior of the Earth. Subducted sediments are particularly important, because they influence the Earth's interior in several ways, and in turn are strongly influenced by the Earth's biosphere. In our model, we use the assumption that a thick sedimentary layer of low permeability on top of the subducting oceanic crust, caused by a biologically enhanced weathering rate, can suppress shallow dewatering. This in turn leads to greater vailability of water in the source region of andesitic partial melt, resulting in an enhanced rate of continental production and regassing rate into the mantle. Our model includes (i) mantle convection, (ii) continental erosion and production, and (iii) mantle water degassing at mid-ocean ridges and regassing at subduction zones. The mantle viscosity of our model depends on (i) the mantle water concentration and (ii) the mantle temperature, whose time dependency is given by radioactive decay of isotopes in the Earth's mantle. Boundary layer theory yields the speed of convection and the water outgassing rate of the Earth's mantle. Our results indicate that present day values of continental surface area and water content of the Earth's mantle represent an attractor in a phase plane spanned by both parameters. We show that the biologic enhancement of the continental erosion rate is important for the system to reach this fixed point. An abiotic Earth tends to reach an alternative stable fixed point with a smaller continental surface area and dryer mantle. The origin and evolution of life on Earth might be responsible for the rise of continents 3.5 billion years ago.

Global pulses of organic carbon burial in deep-sea sediments during glacial maxima

PubMed Central

Cartapanis, Olivier; Bianchi, Daniele; Jaccard, Samuel L.; Galbraith, Eric D.

2016-01-01

The burial of organic carbon in marine sediments removes carbon dioxide from the ocean–atmosphere pool, provides energy to the deep biosphere, and on geological timescales drives the oxygenation of the atmosphere. Here we quantify natural variations in the burial of organic carbon in deep-sea sediments over the last glacial cycle. Using a new data compilation of hundreds of sediment cores, we show that the accumulation rate of organic carbon in the deep sea was consistently higher (50%) during glacial maxima than during interglacials. The spatial pattern and temporal progression of the changes suggest that enhanced nutrient supply to parts of the surface ocean contributed to the glacial burial pulses, with likely additional contributions from more efficient transfer of organic matter to the deep sea and better preservation of organic matter due to reduced oxygen exposure. These results demonstrate a pronounced climate sensitivity for this global carbon cycle sink. PMID:26923945

Recycling of trace elements required for humans in CELSS.

PubMed

Ashida, A

1994-11-01

Recycle of complete nourishment necessary for human should be constructed in CELSS (Controlled Ecological Life Support Systems). Essential elements necessary for human support are categorized as major elements, semi-major elements and trace elements. Recently, trace elements have been identified from considerations of local diseases, food additive problems, pollution problems and adult diseases, consisting of Fe, Zn, Cu, Se, Co, F, Si, Mn, Cr, I, As, Mo, Ni, V, Sn, Li, Br, Cd, Pb, B. A review of the biogeochemical history of the earth's biosphere and the physiological nature of humans and plants explains some of the requirements. A possible route for intake of trace elements is considered that trace elements are dissolved in some chemical form in water, absorbed by plants through their roots and then transfered to human as foods. There may be a possibility that living things absorb some trace elements from atmosphere. Management and recycling of trace elements in CELSS is discussed.

Phytoremediation of heavy metal polluted soils and water: Progresses and perspectives*

PubMed Central

Lone, Mohammad Iqbal; He, Zhen-li; Stoffella, Peter J.; Yang, Xiao-e

2008-01-01

Environmental pollution affects the quality of pedosphere, hydrosphere, atmosphere, lithosphere and biosphere. Great efforts have been made in the last two decades to reduce pollution sources and remedy the polluted soil and water resources. Phytoremediation, being more cost-effective and fewer side effects than physical and chemical approaches, has gained increasing popularity in both academic and practical circles. More than 400 plant species have been identified to have potential for soil and water remediation. Among them, Thlaspi, Brassica, Sedum alfredii H., and Arabidopsis species have been mostly studied. It is also expected that recent advances in biotechnology will play a promising role in the development of new hyperaccumulators by transferring metal hyperaccumulating genes from low biomass wild species to the higher biomass producing cultivated species in the times to come. This paper attempted to provide a brief review on recent progresses in research and practical applications of phytoremediation for soil and water resources. PMID:18357623

Recycling of trace elements required for humans in CELSS

NASA Astrophysics Data System (ADS)

Ashida, A.

1994-11-01

Recycle of complete nourishment necessary for human should be constructed in CELSS (Controlled Ecological Life Support Systems). Essential elements necessary for human support are categorized as major elements, semi-major elements and trace elements. Recently, trace elements have been identified from considerations of local diseases, food additive problems, pollution problems and adult diseases, consisting of Fe, Zn, Cu, Se, Co, F, Si, Mn, Cr, I, As, Mo, Ni, V, Sn, Li, Br, Cd, Pb, B. A review of the biogeochemical history of the earth's biosphere and the physiological nature of humans and plants explains some of the requirements. A possible route for intake of trace elements is considered that trace elements are dissolved in some chemical form in water, absorbed by plants through their roots and then transfered to human as foods. There may be a posibility that living things absorb some trace elements from atmosphere. Management and recycling of trace elements in CELSS is discussed.

Phages in nature

PubMed Central

Millard, Andrew D; Letarov, Andrey V; Heaphy, Shaun

2011-01-01

Bacteriophages or phages are the most abundant organisms in the biosphere and they are a ubiquitous feature of prokaryotic existence. A bacteriophage is a virus which infects a bacterium. Archaea are also infected by viruses, whether these should be referred to as ‘phages’ is debatable, but they are included as such in the scope this article. Phages have been of interest to scientists as tools to understand fundamental molecular biology, as vectors of horizontal gene transfer and drivers of bacterial evolution, as sources of diagnostic and genetic tools and as novel therapeutic agents. Unraveling the biology of phages and their relationship with their hosts is key to understanding microbial systems and their exploitation. In this article we describe the roles of phages in different host systems and show how modeling, microscopy, isolation, genomic and metagenomic based approaches have come together to provide unparalleled insights into these small but vital constituents of the microbial world. PMID:21687533

The Potential Feasibility of Chlorinic Photosynthesis on Exoplanets

NASA Astrophysics Data System (ADS)

Haas, Johnson R.

2010-11-01

The modern search for life-bearing exoplanets emphasizes the potential detection of O2 and O3 absorption spectra in exoplanetary atmospheres as ideal signatures of biology. However, oxygenic photosynthesis may not arise ubiquitously in exoplanetary biospheres. Alternative evolutionary paths may yield planetary atmospheres tinted with the waste products of other dominant metabolisms, including potentially exotic biochemistries. This paper defines chlorinic photosynthesis (CPS) as biologically mediated photolytic oxidation of aqueous Cl- to form halocarbon or dihalogen products, coupled with CO2 assimilation. This hypothetical metabolism appears to be feasible energetically, physically, and geochemically, and could potentially develop under conditions that approximate the terrestrial Archean. It is hypothesized that an exoplanetary biosphere in which chlorinic photosynthesis dominates primary production would tend to evolve a strongly oxidizing, halogen-enriched atmosphere over geologic time. It is recommended that astronomical observations of exoplanetary outgoing thermal emission spectra consider signs of halogenated chemical species as likely indicators of the presence of a chlorinic biosphere. Planets that favor the evolution of CPS would probably receive equivalent or greater surface UV flux than is produced by the Sun, which would promote stronger abiotic UV photolysis of aqueous halides than occurred during Earth's Archean era and impose stronger evolutionary selection pressures on endemic life to accommodate and utilize halogenated compounds. Ocean-bearing planets of stars with metallicities equivalent to, or greater than, the Sun should especially favor the evolution of chlorinic biospheres because of the higher relative seawater abundances of Cl, Br, and I such planets would tend to host. Directed searches for chlorinic biospheres should probably focus on G0-G2, F, and A spectral class stars that have bulk metallicities of +0.0 Dex or greater.

Biospheric feedback effects in a synchronously coupled model of human and Earth systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thornton, Peter E.; Calvin, Katherine; Jones, Andrew D.

Fossil fuel combustion and land-use change are the first and second largest contributors to industrial-era increases in atmospheric carbon dioxide concentration, which is itself the largest driver of present-day climate change1. Projections of fossil fuel consumption and land-use change are thus fundamental inputs for coupled Earth system models (ESM) used to estimate the physical and biological consequences of future climate system forcing2,3. While empirical datasets are available to inform historical analyses4,5, assessments of future climate change have relied on projections of energy and land use based on energy economic models, constrained using historical and present-day data and forced with assumptionsmore » about future policy, land-use patterns, and socio-economic development trajectories6. Here we show that the influence of biospheric change – the integrated effect of climatic, ecological, and geochemical processes – on land ecosystems has a significant impact on energy, agriculture, and land-use projections for the 21st century. Such feedbacks have been ignored in previous ESM studies of future climate. We find that synchronous exposure of land ecosystem productivity in the economic system to biospheric change as it develops in an ESM results in a 10% reduction of land area used for crop cultivation; increased managed forest area and land carbon; a 15-20% decrease in global crop price; and a 17% reduction in fossil fuel emissions for a low-mid range forcing scenario7. These simulation results demonstrate that biospheric change can significantly alter primary human system forcings to the climate system. This synchronous two-way coupling approach removes inconsistencies in description of climate change between human and biosphere components of the coupled model, mitigating a major source of uncertainty identified in assessments of future climate projections8-10.« less

The potential feasibility of chlorinic photosynthesis on exoplanets.

PubMed

Haas, Johnson R

2010-11-01

The modern search for life-bearing exoplanets emphasizes the potential detection of O(2) and O(3) absorption spectra in exoplanetary atmospheres as ideal signatures of biology. However, oxygenic photosynthesis may not arise ubiquitously in exoplanetary biospheres. Alternative evolutionary paths may yield planetary atmospheres tinted with the waste products of other dominant metabolisms, including potentially exotic biochemistries. This paper defines chlorinic photosynthesis (CPS) as biologically mediated photolytic oxidation of aqueous Cl(-) to form halocarbon or dihalogen products, coupled with CO(2) assimilation. This hypothetical metabolism appears to be feasible energetically, physically, and geochemically, and could potentially develop under conditions that approximate the terrestrial Archean. It is hypothesized that an exoplanetary biosphere in which chlorinic photosynthesis dominates primary production would tend to evolve a strongly oxidizing, halogen-enriched atmosphere over geologic time. It is recommended that astronomical observations of exoplanetary outgoing thermal emission spectra consider signs of halogenated chemical species as likely indicators of the presence of a chlorinic biosphere. Planets that favor the evolution of CPS would probably receive equivalent or greater surface UV flux than is produced by the Sun, which would promote stronger abiotic UV photolysis of aqueous halides than occurred during Earth's Archean era and impose stronger evolutionary selection pressures on endemic life to accommodate and utilize halogenated compounds. Ocean-bearing planets of stars with metallicities equivalent to, or greater than, the Sun should especially favor the evolution of chlorinic biospheres because of the higher relative seawater abundances of Cl, Br, and I such planets would tend to host. Directed searches for chlorinic biospheres should probably focus on G0-G2, F, and A spectral class stars that have bulk metallicities of +0.0 Dex or greater.

Turnover of microbial lipids in the deep biosphere and growth of benthic archaeal populations

PubMed Central

Xie, Sitan; Lipp, Julius S.; Wegener, Gunter; Ferdelman, Timothy G.; Hinrichs, Kai-Uwe

2013-01-01

Deep subseafloor sediments host a microbial biosphere with unknown impact on global biogeochemical cycles. This study tests previous evidence based on microbial intact polar lipids (IPLs) as proxies of live biomass, suggesting that Archaea dominate the marine sedimentary biosphere. We devised a sensitive radiotracer assay to measure the decay rate of ([14C]glucosyl)-diphytanylglyceroldiether (GlcDGD) as an analog of archaeal IPLs in continental margin sediments. The degradation kinetics were incorporated in model simulations that constrained the fossil fraction of subseafloor IPLs and rates of archaeal turnover. Simulating the top 1 km in a generic continental margin sediment column, we estimated degradation rate constants of GlcDGD being one to two orders of magnitude lower than those of bacterial IPLs, with half-lives of GlcDGD increasing with depth to 310 ky. Given estimated microbial community turnover times of 1.6–73 ky in sediments deeper than 1 m, 50–96% of archaeal IPLs represent fossil signals. Consequently, previous lipid-based estimates of global subseafloor biomass probably are too high, and the widely observed dominance of archaeal IPLs does not rule out a deep biosphere dominated by Bacteria. Reverse modeling of existing concentration profiles suggest that archaeal IPL synthesis rates decline from around 1,000 pg⋅mL−1 sediment⋅y−1 at the surface to 0.2 pg⋅mL−1⋅y−1 at 1 km depth, equivalent to production of 7 × 105 to 140 archaeal cells⋅mL−1 sediment⋅y−1, respectively. These constraints on microbial growth are an important step toward understanding the relationship between the deep biosphere and the carbon cycle. PMID:23530229

Earth Applications of Closed Ecological Systems: Relevance to the Development of Sustainability in our Global Biosphere

NASA Astrophysics Data System (ADS)

Dempster, W.; van Thillo, M.; Alling, A.; Allen, J.; Silverstone, S.; Nelson, M.

The parallels between the challenges facing bioregenerative life support and closed ecological systems and those in our global biosphere are striking. At the scale of the current global technosphere and human population, it is increasingly obvious that the biosphere can no longer be counted on to be vast enough to safely buffer and absorb technogenic and anthropogenic pollutants. With an increasing percentage of the world's natural resources and primary productivity being dictated by, and directed to, humans, our species is starting to appreciate its survival and quality of life depends on regulating its activities, and insuring that crucial biogeochemical cycles continue to function. This shift of consciousness has led to the widespread call for moving towards the sustainability of human activities. For researchers working on bioreenerative life support, the small volumes and faster cycling times have made it obvious that systems must be created in to ensure renewal of water and atmosphere, nutrient recycling, and where all technical systems can be safely integrated with the maintenance of safe environmental conditions. The development of technical systems that can be fully integrated with the living systems that they support should be a harbinger of new perspectives in the global environment. The paper will review some of these environmental technologies which are emerging from bioregenerative life support system research such as high-yield intensive agricultural methods, waste treatment and nutrient recycling, air purification, modeling, sensor and control systems and their potential applications in the global biosphere. In addition, a review of the human experience in closed ecological systems shows that these can offer opportunities for public education and consciousness-changing of how humans regard our global biosphere.

A statistical approach for isolating fossil fuel emissions in atmospheric inverse problems

DOE PAGES

Yadav, Vineet; Michalak, Anna M.; Ray, Jaideep; ...

2016-10-27

We study independent verification and quantification of fossil fuel (FF) emissions that constitutes a considerable scientific challenge. By coupling atmospheric observations of CO 2 with models of atmospheric transport, inverse models offer the possibility of overcoming this challenge. However, disaggregating the biospheric and FF flux components of terrestrial fluxes from CO 2 concentration measurements has proven to be difficult, due to observational and modeling limitations. In this study, we propose a statistical inverse modeling scheme for disaggregating winter time fluxes on the basis of their unique error covariances and covariates, where these covariances and covariates are representative of the underlyingmore » processes affecting FF and biospheric fluxes. The application of the method is demonstrated with one synthetic and two real data prototypical inversions by using in situ CO 2 measurements over North America. Also, inversions are performed only for the month of January, as predominance of biospheric CO 2 signal relative to FF CO 2 signal and observational limitations preclude disaggregation of the fluxes in other months. The quality of disaggregation is assessed primarily through examination of a posteriori covariance between disaggregated FF and biospheric fluxes at regional scales. Findings indicate that the proposed method is able to robustly disaggregate fluxes regionally at monthly temporal resolution with a posteriori cross covariance lower than 0.15 µmol m -2 s -1 between FF and biospheric fluxes. Error covariance models and covariates based on temporally varying FF inventory data provide a more robust disaggregation over static proxies (e.g., nightlight intensity and population density). However, the synthetic data case study shows that disaggregation is possible even in absence of detailed temporally varying FF inventory data.« less

Turnover of microbial lipids in the deep biosphere and growth of benthic archaeal populations.

PubMed

Xie, Sitan; Lipp, Julius S; Wegener, Gunter; Ferdelman, Timothy G; Hinrichs, Kai-Uwe

2013-04-09

Deep subseafloor sediments host a microbial biosphere with unknown impact on global biogeochemical cycles. This study tests previous evidence based on microbial intact polar lipids (IPLs) as proxies of live biomass, suggesting that Archaea dominate the marine sedimentary biosphere. We devised a sensitive radiotracer assay to measure the decay rate of ([(14)C]glucosyl)-diphytanylglyceroldiether (GlcDGD) as an analog of archaeal IPLs in continental margin sediments. The degradation kinetics were incorporated in model simulations that constrained the fossil fraction of subseafloor IPLs and rates of archaeal turnover. Simulating the top 1 km in a generic continental margin sediment column, we estimated degradation rate constants of GlcDGD being one to two orders of magnitude lower than those of bacterial IPLs, with half-lives of GlcDGD increasing with depth to 310 ky. Given estimated microbial community turnover times of 1.6-73 ky in sediments deeper than 1 m, 50-96% of archaeal IPLs represent fossil signals. Consequently, previous lipid-based estimates of global subseafloor biomass probably are too high, and the widely observed dominance of archaeal IPLs does not rule out a deep biosphere dominated by Bacteria. Reverse modeling of existing concentration profiles suggest that archaeal IPL synthesis rates decline from around 1,000 pg⋅mL(-1) sediment⋅y(-1) at the surface to 0.2 pg⋅mL(-1)⋅y(-1) at 1 km depth, equivalent to production of 7 × 10(5) to 140 archaeal cells⋅mL(-1) sediment⋅y(-1), respectively. These constraints on microbial growth are an important step toward understanding the relationship between the deep biosphere and the carbon cycle.

Atribacteria from the Subseafloor Sedimentary Biosphere Disperse to the Hydrosphere through Submarine Mud Volcanoes.

PubMed

Hoshino, Tatsuhiko; Toki, Tomohiro; Ijiri, Akira; Morono, Yuki; Machiyama, Hideaki; Ashi, Juichiro; Okamura, Kei; Inagaki, Fumio

2017-01-01

Submarine mud volcanoes (SMVs) are formed by muddy sediments and breccias extruded to the seafloor from a source in the deep subseafloor and are characterized by the discharge of methane and other hydrocarbon gasses and deep-sourced fluids into the overlying seawater. Although SMVs act as a natural pipeline connecting the Earth's surface and subsurface biospheres, the dispersal of deep-biosphere microorganisms and their ecological roles remain largely unknown. In this study, we investigated the microbial communities in sediment and overlying seawater at two SMVs located on the Ryukyu Trench off Tanegashima Island, southern Japan. The microbial communities in mud volcano sediments were generally distinct from those in the overlying seawaters and in the well-stratified Pacific margin sediments collected at the Peru Margin, the Juan de Fuca Ridge flank off Oregon, and offshore of Shimokita Peninsula, northeastern Japan. Nevertheless, in-depth analysis of different taxonomic groups at the sub-species level revealed that the taxon affiliated with Atribacteria , heterotrophic anaerobic bacteria that typically occur in organic-rich anoxic subseafloor sediments, were commonly found not only in SMV sediments but also in the overlying seawater. We designed a new oligonucleotide probe for detecting Atribacteria using the catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH). CARD-FISH, digital PCR and sequencing analysis of 16S rRNA genes consistently showed that Atribacteria are abundant in the methane plumes of the two SMVs (0.58 and 1.5 × 10 4 cells/mL, respectively) but not in surrounding waters, suggesting that microbial cells in subseafloor sediments are dispersed as "deep-biosphere seeds" into the ocean. These findings may have important implications for the microbial transmigration between the deep subseafloor biosphere and the hydrosphere.

Atribacteria from the Subseafloor Sedimentary Biosphere Disperse to the Hydrosphere through Submarine Mud Volcanoes

PubMed Central

Hoshino, Tatsuhiko; Toki, Tomohiro; Ijiri, Akira; Morono, Yuki; Machiyama, Hideaki; Ashi, Juichiro; Okamura, Kei; Inagaki, Fumio

2017-01-01

Submarine mud volcanoes (SMVs) are formed by muddy sediments and breccias extruded to the seafloor from a source in the deep subseafloor and are characterized by the discharge of methane and other hydrocarbon gasses and deep-sourced fluids into the overlying seawater. Although SMVs act as a natural pipeline connecting the Earth’s surface and subsurface biospheres, the dispersal of deep-biosphere microorganisms and their ecological roles remain largely unknown. In this study, we investigated the microbial communities in sediment and overlying seawater at two SMVs located on the Ryukyu Trench off Tanegashima Island, southern Japan. The microbial communities in mud volcano sediments were generally distinct from those in the overlying seawaters and in the well-stratified Pacific margin sediments collected at the Peru Margin, the Juan de Fuca Ridge flank off Oregon, and offshore of Shimokita Peninsula, northeastern Japan. Nevertheless, in-depth analysis of different taxonomic groups at the sub-species level revealed that the taxon affiliated with Atribacteria, heterotrophic anaerobic bacteria that typically occur in organic-rich anoxic subseafloor sediments, were commonly found not only in SMV sediments but also in the overlying seawater. We designed a new oligonucleotide probe for detecting Atribacteria using the catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH). CARD-FISH, digital PCR and sequencing analysis of 16S rRNA genes consistently showed that Atribacteria are abundant in the methane plumes of the two SMVs (0.58 and 1.5 × 104 cells/mL, respectively) but not in surrounding waters, suggesting that microbial cells in subseafloor sediments are dispersed as “deep-biosphere seeds” into the ocean. These findings may have important implications for the microbial transmigration between the deep subseafloor biosphere and the hydrosphere. PMID:28676800

Development of model for studies on momentum transfer in electrochemical cells with entry region coil as turbulence promoter

NASA Astrophysics Data System (ADS)

Penta Rao, Tamarba; Rajendra Prasad, P.

2018-04-01

Entry region swirl promoters gain importance in industry because of its effectiveness in augmentation of mass and heat transfer augmentation. Design of equipment needs momentum transfer data along with mass or heat transfer data. Hence an experimental investigation was carried out with coaxially placed entry region spiral coil as turbulence promoters on momentum transfer in forced convection flow of electrolyte in circular conduits. Aqueous solution of sodium hydroxide and 0.01 M equimolal Ferri-ferro cyanide system was chosen for the study. The study covered parameters like effect of pitch of the coil, effect of length of the coil, diameter of the coil, diameter of the coil wire, diameter of the annular rod. The promoter is measured by limiting current technique using diffusion controlled electrochemical reactions. The study comprises of evaluation of momentum transfer rates at the outer wall of the electrochemical cell. Pressure drop measurements were also made to obtain the energy consumption pattern. Within the range of variables covered. The results are correlated by the momentum transfer similarity function. Momentum transfer coefficients were evaluated from measured limiting currents. Effect of each parameter was studied in terms of friction factor. A model was developed for momentum transfer. The experimental data on momentum transfer was modeled in terms of momentum transfer function and Reynolds number, geometric parameters.

Land-Atmosphere Interactions: Successes, Problems and Prospects

NASA Technical Reports Server (NTRS)

Sud, Y. C.; Mocko, D. M.

1999-01-01

After two decades of active research, a much better understanding of the broader role of biospheric processes on the local climate has emerged. A surface-albedo increase, particularly in desert border regions of the subtropics (as well as the deforested tropical regions), leads to a net surface energy deficit, which in turn leads to a relative sinking and reduced rainfall. On the other hand, studies of the influence of altered ratios of evapotranspiration and sensible fluxes, in situations where the net solar income is unchanged, show that evapotranspiration is a more desirable flux for increased precipitation and vitality of the biosphere. Besides providing water vapor and convective available potential energy (CAPE) to the lower troposphere, evapotranspiration helps in building larger CAPE before "turning on" the moist-convection. Larger CAPE in the lower troposphere enables convection to reach into the deeper atmosphere thereby heating the upper troposphere; indeed, moist-convection is also accompanied by the evaporation of falling precipitation that cools and moistens the lower atmosphere. While convective, as opposed to stratiform, precipitation reduces the fractional cloud cover; it also allows more solar radiation to reach the surface thereby invigorating surface fluxes. These, together with moist convection and associated downdrafts help to maintain the characteristic upper temperature limit(s) of the moist-land as well as oceanic regions. Regardless of the above understanding, several important problems continue to hinder the accurate simulation of a realistic land atmosphere interaction in a numerical model (both GCM and/or Meso-scale models). Among the unsolved problems are parameterization of sub-grid scale land processes that include small-scale variability of soil moisture, snow-cover and snow-physics, the biodiversity of the biosphere, orography, local drainage characteristics under natural conditions, and surface flow over the natural terrain. A well-known non-linear response of surface fluxes to these variations makes the problem of parameterizing land-atmosphere interaction processes hard-to-address and simulate, particularly in a GCM. In our presentation, we will discuss how orographic, snow-cover, and water table interactions can be included into a Simple Biosphere Model such as SiB/SSiB. Figure I shows how, in the Russian region, spring snowmelt affects the soil moisture profile. Corresponding figure 2 shows how interaction with the water table decreases the natural evapotranspiration in the Sahel region simulation. While these simulations need better validation with data, the simulations reveal that surface processes are sensitive to these parameterizations. With these developments, we continue to advance our understanding of the interaction of land with the atmosphere aloft, but the intrinsic variability of the newer parameters, e. g., hydraulic properties of the soil, diminish the positive influences of these advances on the improved climate simulation with GCMs.

Space observations for global and regional studies of the biosphere

NASA Technical Reports Server (NTRS)

Cihlar, J.; Li, Z.; Chen, J.; Sellers, P.; Hall, F.

1994-01-01

The capability to make space-based measurements of Earth at high spatial and temporal resolutions, which would not otherwise be economically or practically feasible, became available just in time to contribute to scientific understanding of the interactive processes governing the total Earth system. Such understanding has now become essential in order to take practical steps which would counteract or mitigate the pervasive impact of the growing human population on the future habitability of the Earth. The paper reviews the rationale for using space observations for studies of climate and terrestrial ecosystems at global and regional scales, as well as the requirements for such observations for studies of climate and ecosystem dynamics. The present status of these developments is reported along with initiatives under way to advance the use of satellite observations for Earth system studies. The most important contribution of space observations is the provision of physical or biophysical parameters for models representing various components of the Earth system. Examples of such parameters are given for climatic and ecosystem studies.

Toward an understanding of global change: Initial priorities for US contributions to the International Geosphere-Biosphere Program

NASA Technical Reports Server (NTRS)

1988-01-01

A limited number of high-priority research initiatives are recommended for early implementation as part of the U.S. contribution to the preparatory phase of the International Geosphere-Biosphere Program. The recommendations are based on the committee's analysis of the most critical gaps in the scientific knowledge needed to understand the changes that are occurring in the earth system not being addressed by existing programs. The report articulates a number of important key issues and interactions that characterize global change in the geosphere-biosphere system on time scales of decades to centuries; identifies the knowledge that is the most urgently needed to improve understanding of those issues and interactions; and formulates initial priorities for initial U.S. contributions to the IGBP, recognizing the contributions of other ongoing and proposed programs.

A modern earth narrative: What will be the fate of the biosphere?

USGS Publications Warehouse

Williams, R.S.

2000-01-01

The modern Earth Narrative is the scientific description of the natural and human history of the Earth, and it is based on two fundamental concepts: Deep (or Geologic) Time and Biological Evolution. Changes in the Earth's biosphere and geosphere are discussed from the perspective of natural variability and impacts of the rapid increase in the human population. The failure of humans to comprehend and understand the Earth Narrative, especially the place of humans in it, presages dire consequences for the Earth's biosphere. The actions humans take, individually and collectively, during the 21st century will likely determine the fate of many millions of species, including our own. It is argued that we must quickly establish an Earth System-based conservation ethic that has the objective of complete preservation of the Earth's biotic inheritance. Published by Elsevier Science Ltd.

The Compressible Laminar Boundary Layer with Heat Transfer and Arbitrary Pressure Gradient

NASA Technical Reports Server (NTRS)

Cohen, Clarence B; Reshotko, Eli

1956-01-01

An approximate method for the calculation of the compressible laminar boundary layer with heat transfer and arbitrary pressure gradient, based on Thwaites' correlation concept, is presented. With the definition of dimensionless shear and heat-transfer parameters and an assumed correlation of these parameters in terms of a momentum parameter, a complete system of relations for calculating skin friction and heat transfer results. Knowledge of velocity or temperature profiles is not necessary in using this calculation method. When the method is applied to a convergent-divergent, axially symmetric rocket nozzle, it shows that high rates of heat transfer are obtained at the initial stagnation point and at the throat of the nozzle. Also indicated are negative displacement thicknesses in the convergent portion of the nozzle; these occur because of the high density within the lower portions of the cooled boundary layer. (author)

Lidar Remote Sensing of Forests: New Instruments and Modeling Capabilities

NASA Technical Reports Server (NTRS)

Cook, Bruce D.

2012-01-01

Lidar instruments provide scientists with the unique opportunity to characterize the 3D structure of forest ecosystems. This information allows us to estimate properties such as wood volume, biomass density, stocking density, canopy cover, and leaf area. Structural information also can be used as drivers for photosynthesis and ecosystem demography models to predict forest growth and carbon sequestration. All lidars use time-in-flight measurements to compute accurate ranging measurements; however, there is a wide range of instruments and data types that are currently available, and instrument technology continues to advance at a rapid pace. This seminar will present new technologies that are in use and under development at NASA for airborne and space-based missions. Opportunities for instrument and data fusion will also be discussed, as Dr. Cook is the PI for G-LiHT, Goddard's LiDAR, Hyperspectral, and Thermal airborne imager. Lastly, this talk will introduce radiative transfer models that can simulate interactions between laser light and forest canopies. Developing modeling capabilities is important for providing continuity between observations made with different lidars, and to assist the design of new instruments. Dr. Bruce Cook is a research scientist in NASA's Biospheric Sciences Laboratory at Goddard Space Flight Center, and has more than 25 years of experience conducting research on ecosystem processes, soil biogeochemistry, and exchange of carbon, water vapor and energy between the terrestrial biosphere and atmosphere. His research interests include the combined use of lidar, hyperspectral, and thermal data for characterizing ecosystem form and function. He is Deputy Project Scientist for the Landsat Data Continuity Mission (LDCM); Project Manager for NASA s Carbon Monitoring System (CMS) pilot project for local-scale forest biomass; and PI of Goddard's LiDAR, Hyperspectral, and Thermal (G-LiHT) airborne imager.

An Agent-Based Interface to Terrestrial Ecological Forecasting

NASA Technical Reports Server (NTRS)

Golden, Keith; Nemani, Ramakrishna; Pang, Wanlin; Votava, Petr

2005-01-01

The latest generation of NASA Earth Observing System (EOS) satellites has brought a new dimension to continuous monitoring of the living part of the Earth System, the biosphere. EOS data can now provide weekly global measures of vegetation productivity and ocean chlorophyll, and many related biophysical factors such as land cover changes or snowmelt rates. However, the highest economic value would come from forecasting impending conditions of the biosphere, to allow decision makers to mitigate dangers or exploit positive trends. NASA's strategic plan for the Earth Science Enterprise i d e n a s ecological forecasting as a focus for research. Ecological forecasting predicts the effects of changes in the physical, chemical and biological environment on ecosystem activity. Possible applications of such a system include predicting shortfalls or bumper crops of agricultural production, populations of threatened or invasive species or wildfire danger in time to allow improves preparation and logistical efficiency. Petabytes of remote sensing data are now available to help measure, understand and forecast changes in the Earth system, but using these data effectively can be surprisingly hard. The volume and variety of data files and formats are daunting. Simple data management activities, such as locating and transferring files, changing file formats, gridding point data, and scaling and reprojecting gridded data, can consume far more personnel time and resources than the actual data analysis. Some scientists commit to a particular data source or resolution just because using anything different would be more effort that it's worth. Better tools can help, but most of the tools developed to date are little more than shell scripts; they lack the flexibility to meet the diverse needs of users and are difficult to extend to handle changes in available data sources.

Partitioning net ecosystem carbon exchange into net assimilation and respiration using 13CO2 measurements: A cost-effective sampling strategy

NASA Astrophysics Data System (ADS)

OgéE, J.; Peylin, P.; Ciais, P.; Bariac, T.; Brunet, Y.; Berbigier, P.; Roche, C.; Richard, P.; Bardoux, G.; Bonnefond, J.-M.

2003-06-01

The current emphasis on global climate studies has led the scientific community to set up a number of sites for measuring the long-term biosphere-atmosphere net CO2 exchange (net ecosystem exchange, NEE). Partitioning this flux into its elementary components, net assimilation (FA), and respiration (FR), remains necessary in order to get a better understanding of biosphere functioning and design better surface exchange models. Noting that FR and FA have different isotopic signatures, we evaluate the potential of isotopic 13CO2 measurements in the air (combined with CO2 flux and concentration measurements) to partition NEE into FR and FA on a routine basis. The study is conducted at a temperate coniferous forest where intensive isotopic measurements in air, soil, and biomass were performed in summer 1997. The multilayer soil-vegetation-atmosphere transfer model MuSICA is adapted to compute 13CO2 flux and concentration profiles. Using MuSICA as a "perfect" simulator and taking advantage of the very dense spatiotemporal resolution of the isotopic data set (341 flasks over a 24-hour period) enable us to test each hypothesis and estimate the performance of the method. The partitioning works better in midafternoon when isotopic disequilibrium is strong. With only 15 flasks, i.e., two 13CO2 nighttime profiles (to estimate the isotopic signature of FR) and five daytime measurements (to perform the partitioning) we get mean daily estimates of FR and FA that agree with the model within 15-20%. However, knowledge of the mesophyll conductance seems crucial and may be a limitation to the method.

Respiratory Pathways Reconstructed by Multi-Omics Analysis in Melioribacter roseus, Residing in a Deep Thermal Aquifer of the West-Siberian Megabasin

PubMed Central

Gavrilov, Sergey; Podosokorskaya, Olga; Alexeev, Dmitry; Merkel, Alexander; Khomyakova, Maria; Muntyan, Maria; Altukhov, Ilya; Butenko, Ivan; Bonch-Osmolovskaya, Elizaveta; Govorun, Vadim; Kublanov, Ilya

2017-01-01

Melioribacter roseus, a representative of recently proposed Ignavibacteriae phylum, is a metabolically versatile thermophilic bacterium, inhabiting subsurface biosphere of the West-Siberian megabasin and capable of growing on various substrates and electron acceptors. Genomic analysis followed by inhibitor studies and membrane potential measurements of aerobically grown M. roseus cells revealed the activity of aerobic respiratory electron transfer chain comprised of respiratory complexes I and IV, and an alternative complex III. Phylogeny reconstruction revealed that oxygen reductases belonged to atypical cc(o/b)o3-type and canonical cbb3–type cytochrome oxidases. Also, two molybdoenzymes of M. roseus were affiliated either with Ttr or Psr/Phs clades, but not with typical respiratory arsenate reductases of the Arr clade. Expression profiling, both at transcripts and protein level, allowed us to assign the role of the terminal respiratory oxidase under atmospheric oxygen concentration for the cc(o/b)o3 cytochrome oxidase, previously proposed to serve for oxygen detoxification only. Transcriptomic analysis revealed the involvement of both molybdoenzymes of M. roseus in As(V) respiration, yet differences in the genomic context of their gene clusters allow to hypothesize about their distinct roles in arsenate metabolism with the ‘Psr/Phs’-type molybdoenzyme being the most probable candidate respiratory arsenate reductase. Basing on multi-omics data, the pathways for aerobic and arsenate respiration were proposed. Our results start to bridge the vigorously increasing gap between homology-based predictions and experimentally verified metabolic processes, what is especially important for understudied microorganisms of novel lineages from deep subsurface environments of Eurasia, which remained separated from the rest of the biosphere for several geological periods. PMID:28713355

Resistance of Terrestrial Microbial Communities to Impack of Physical Conditinos of Subsurface Layers of Martian Regolith

NASA Astrophysics Data System (ADS)

Cheptsov, V. S.; Vorobyova, E. A.

2017-05-01

Currently, astrobiology is focused on Mars as one of the most perspective objects in the Solar System to search for microbial life. It was assumed that the putative biosphere of Mars could be cryopreserved and had been stored for billions of years in anabiotic state like microbial communities of Arctic and Antarctic permafrost deposits have been preserved till now for millions of years. In this case microbial cells should be not able to repair the damages or these processes have to be significantly depressed, and the main factor causing cell's death should be ionizing radiation. In a series of experiments we simulated the effects of combination of physical factors known as characteristics of the Martian regolith (and close to the space environment) on the natural microbial communities inhabiting xerophytic harsh habitats with extreme temperature conditions: polar permafrost and desert soils. The aim of the study was to examine the cumulative effect of factors (gamma radiation, low temperature, low pressure) to assess the possibility of metabolic reactions, and to find limits of the viability of natural microbial communities after exposure to the given conditions. It was found that microbial biomarkers could be reliably detected in soil samples after radiation dose accumulation up to 1 MGy (not further investigated) in combination with exposure to low temperature and low pressure. Resistance to extremely high doses of radiation in simulated conditions proves that if there was an Earth-like biosphere on the early Mars microorganisms could survive in the surface or subsurface layers of the Martian regolith for more than tens of millions of years after climate change. The study gives also some new grounds for the approval of transfer of viable microorganisms in space.

Intergovernmental Conference of Experts on the Scientific Basis for Rational Use and Conservation of the Resources of the Biosphere (Paris, France, September 4-13, 1968), Recommendations.

ERIC Educational Resources Information Center

United Nations Educational, Scientific, and Cultural Organization, Paris (France).

This document contains twenty recommendations put forth at the Intergovernmental Conference of Experts on the Scientific Basis for Rational Use and Conservation of the Resources of the Biosphere under the direction of UNESCO (United Nations Educational, Scientific and Cultural Organization). The conference was held at the UNESCO House, Paris,…

Studies of land-cover, land-use, and biophysical properties of vegetation in the Large Scale Biosphere Atmosphere experiment in Amazonia.

Treesearch

Dar A. Robertsa; Michael Keller; Joao Vianei Soares

2003-01-01

We summarize early research on land-cover, land-use, and biophysical properties of vegetation from the Large Scale Biosphere Atmosphere (LBA) experiment in Amazoˆnia. LBA is an international research program developed to evaluate regional function and to determine how land-use and climate modify biological, chemical and physical processes there. Remote sensing has...

Effects of primitive photosynthesis on Earth's early climate system

NASA Astrophysics Data System (ADS)

Ozaki, Kazumi; Tajika, Eiichi; Hong, Peng K.; Nakagawa, Yusuke; Reinhard, Christopher T.

2018-01-01

The evolution of different forms of photosynthetic life has profoundly altered the activity level of the biosphere, radically reshaping the composition of Earth's oceans and atmosphere over time. However, the mechanistic impacts of a primitive photosynthetic biosphere on Earth's early atmospheric chemistry and climate are poorly understood. Here, we use a global redox balance model to explore the biogeochemical and climatological effects of different forms of primitive photosynthesis. We find that a hybrid ecosystem of H2-based and Fe2+-based anoxygenic photoautotrophs—organisms that perform photosynthesis without producing oxygen—gives rise to a strong nonlinear amplification of Earth's methane (CH4) cycle, and would thus have represented a critical component of Earth's early climate system before the advent of oxygenic photosynthesis. Using a Monte Carlo approach, we find that a hybrid photosynthetic biosphere widens the range of geochemical conditions that allow for warm climate states well beyond either of these metabolic processes acting in isolation. Our results imply that the Earth's early climate was governed by a novel and poorly explored set of regulatory feedbacks linking the anoxic biosphere and the coupled H, C and Fe cycles. We suggest that similar processes should be considered when assessing the potential for sustained habitability on Earth-like planets with reducing atmospheres.

Intraterrestrial life in igneous ocean crust: advances, technologies, and the future (Invited)

NASA Astrophysics Data System (ADS)

Edwards, K. J.; Wheat, C. G.

2010-12-01

The “next frontier” of scientific investigation in the deep sub-seafloor microbial biosphere lies in a realm that has been a completely unexplored until just the past decade: the igneous oceanic crust. Problems that have hampered exploration of the “hard rock” marine deep biosphere have revolved around sample access (hard rock drilling is technologically complex), contamination (a major hurdle), momentum (why take on this challenge when the relatively “easier” marine muds also have been a frontier) and suspicion that microbes in more readily accessed using (simpler) non-drilling technologies - like vents - are truly are endemic of subsurface clades/activities. Since the late 1990’s, however, technologies and resultant studies on microbes in the igneous ocean crust deep biosphere have risen sharply, and offer a new and distinct view on this biome. Moreover, microbiologists are now taking leading roles in technological developments that are critically required to address this biosphere - interfacing and collaborating closely with engineers, genomic biologists, geologists, seismologists, and geochemists to accomplish logistically complex and long-term studies that bring observatory research to this deep realm. The future of this field for the least decade is rich - opportunities abound for microbiologists to play new roles in how we study microbiology in the deep subsurface in an oceanographic and Earth system science perspective.

Searching for a shadow biosphere on Earth as a test of the 'cosmic imperative'.

PubMed

Davies, P C W

2011-02-13

Estimates for the number of communicating civilizations in the galaxy, based on the so-called Drake equation, are meaningless without a plausible estimate for the probability that life will emerge on an Earth-like planet. In the absence of a theory of the origin of life, that number can be anywhere from 0 to 1. Distinguished scientists have been known to argue that life on Earth is a freak accident, unique in the observable universe and, conversely, that life is almost bound to arise in the course of time, given Earth-like conditions. De Duve, adopting the latter position, coined the phrase that 'life is a cosmic imperative'. De Duve's position would be immediately verified if we were to discover a second sample of life that we could be sure arose from scratch independently of known life. Given the current absence of evidence for life beyond Earth, the best way to test the hypothesis of the cosmic imperative is to see whether terrestrial life began more than once. If it did, it is possible that descendants of a second genesis might be extant, forming a sort of 'shadow biosphere' existing alongside, or perhaps interpenetrating, the known biosphere. I outline a strategy to detect the existence of such a shadow biosphere.

Life in a dark biosphere: a review of circadian physiology in "arrhythmic" environments.

PubMed

Beale, Andrew David; Whitmore, David; Moran, Damian

2016-12-01

Most of the life with which humans interact is exposed to highly rhythmic and extremely predictable changes in illumination that occur with the daily events of sunrise and sunset. However, while the influence of the sun feels omnipotent to surface dwellers such as ourselves, life on earth is dominated, in terms of biomass, by organisms isolated from the direct effects of the sun. A limited understanding of what life is like away from the sun can be inferred from our knowledge of physiology and ecology in the light biosphere, but a full understanding can only be gained by studying animals from the dark biosphere, both in the laboratory and in their natural habitats. One of the least understood aspects of life in the dark biosphere is the rhythmicity of physiology and what it means to live in an environment of low or no rhythmicity. Here we describe methods that may be used to understand rhythmic physiology in the dark and summarise some of the studies of rhythmic physiology in "arrhythmic" environments, such as the poles, deep sea and caves. We review what can be understood about the adaptive value of rhythmic physiology on the Earth's surface from studies of animals from arrhythmic environments and what role a circadian clock may play in the dark.

Microbial metagenomes from three aquifers in the Fennoscandian shield terrestrial deep biosphere reveal metabolic partitioning among populations

PubMed Central

Wu, Xiaofen; Holmfeldt, Karin; Hubalek, Valerie; Lundin, Daniel; Åström, Mats; Bertilsson, Stefan; Dopson, Mark

2016-01-01

Microorganisms in the terrestrial deep biosphere host up to 20% of the earth's biomass and are suggested to be sustained by the gases hydrogen and carbon dioxide. A metagenome analysis of three deep subsurface water types of contrasting age (from <20 to several thousand years) and depth (171 to 448 m) revealed phylogenetically distinct microbial community subsets that either passed or were retained by a 0.22 μm filter. Such cells of <0.22 μm would have been overlooked in previous studies relying on membrane capture. Metagenomes from the three water types were used for reconstruction of 69 distinct microbial genomes, each with >86% coverage. The populations were dominated by Proteobacteria, Candidate divisions, unclassified archaea and unclassified bacteria. The estimated genome sizes of the <0.22 μm populations were generally smaller than their phylogenetically closest relatives, suggesting that small dimensions along with a reduced genome size may be adaptations to oligotrophy. Shallow ‘modern marine' water showed community members with a predominantly heterotrophic lifestyle. In contrast, the deeper, ‘old saline' water adhered more closely to the current paradigm of a hydrogen-driven deep biosphere. The data were finally used to create a combined metabolic model of the deep terrestrial biosphere microbial community. PMID:26484735

Microbial metagenomes from three aquifers in the Fennoscandian shield terrestrial deep biosphere reveal metabolic partitioning among populations.

PubMed

Wu, Xiaofen; Holmfeldt, Karin; Hubalek, Valerie; Lundin, Daniel; Åström, Mats; Bertilsson, Stefan; Dopson, Mark

2016-05-01

Microorganisms in the terrestrial deep biosphere host up to 20% of the earth's biomass and are suggested to be sustained by the gases hydrogen and carbon dioxide. A metagenome analysis of three deep subsurface water types of contrasting age (from <20 to several thousand years) and depth (171 to 448 m) revealed phylogenetically distinct microbial community subsets that either passed or were retained by a 0.22 μm filter. Such cells of <0.22 μm would have been overlooked in previous studies relying on membrane capture. Metagenomes from the three water types were used for reconstruction of 69 distinct microbial genomes, each with >86% coverage. The populations were dominated by Proteobacteria, Candidate divisions, unclassified archaea and unclassified bacteria. The estimated genome sizes of the <0.22 μm populations were generally smaller than their phylogenetically closest relatives, suggesting that small dimensions along with a reduced genome size may be adaptations to oligotrophy. Shallow 'modern marine' water showed community members with a predominantly heterotrophic lifestyle. In contrast, the deeper, 'old saline' water adhered more closely to the current paradigm of a hydrogen-driven deep biosphere. The data were finally used to create a combined metabolic model of the deep terrestrial biosphere microbial community.

Community structure of rare methanogenic archaea: insight from a single functional group

PubMed Central

Winkel, Matthias; Wagner, Dirk

2017-01-01

Abstract The rare biosphere, the low abundant microbial populations, is suggested to be a conserved way of microbial life. Here we conducted a molecular survey of rare methanogenic archaea in the environment targeting the mcrA gene in order to test if general concepts associated with the structure of the rare bacterial biosphere also apply to single functional groups. Similar to what is known about rare bacterial communities, the contribution of rare methanogens to the alpha diversity is much larger than to Bray-Curtis measures. Moreover, a similar core group of methanogens harbored by the abundant and rare communities suggests similar sources and environmental controls of both groups. Among the communities of different levels of rarity, the conditionally rare methanogenic taxa largely account for the overall community dynamics of the rare biosphere and likely enter the dominant community under favorable environmental conditions. In addition, we observed a positive correlation between the alpha diversity and the production of methane when the rare taxa were taken into account. This supports the concept that increasing microbial biodiversity enhances ecological function. The composition and environmental associations of the rare methanogenic biosphere allow us to conclude that rarity is a conserved way also for single functional groups. PMID:29029047

Sensitivity Analysis for Steady State Groundwater Flow Using Adjoint Operators

NASA Astrophysics Data System (ADS)

Sykes, J. F.; Wilson, J. L.; Andrews, R. W.

1985-03-01

Adjoint sensitivity theory is currently being considered as a potential method for calculating the sensitivity of nuclear waste repository performance measures to the parameters of the system. For groundwater flow systems, performance measures of interest include piezometric heads in the vicinity of a waste site, velocities or travel time in aquifers, and mass discharge to biosphere points. The parameters include recharge-discharge rates, prescribed boundary heads or fluxes, formation thicknesses, and hydraulic conductivities. The derivative of a performance measure with respect to the system parameters is usually taken as a measure of sensitivity. To calculate sensitivities, adjoint sensitivity equations are formulated from the equations describing the primary problem. The solution of the primary problem and the adjoint sensitivity problem enables the determination of all of the required derivatives and hence related sensitivity coefficients. In this study, adjoint sensitivity theory is developed for equations of two-dimensional steady state flow in a confined aquifer. Both the primary flow equation and the adjoint sensitivity equation are solved using the Galerkin finite element method. The developed computer code is used to investigate the regional flow parameters of the Leadville Formation of the Paradox Basin in Utah. The results illustrate the sensitivity of calculated local heads to the boundary conditions. Alternatively, local velocity related performance measures are more sensitive to hydraulic conductivities.

Priority design parameters of industrialized optical fiber sensors in civil engineering

NASA Astrophysics Data System (ADS)

Wang, Huaping; Jiang, Lizhong; Xiang, Ping

2018-03-01

Considering the mechanical effects and the different paths for transferring deformation, optical fiber sensors commonly used in civil engineering have been systematically classified. Based on the strain transfer theory, the relationship between the strain transfer coefficient and allowable testing error is established. The proposed relationship is regarded as the optimal control equation to obtain the optimal value of sensors that satisfy the requirement of measurement precision. Furthermore, specific optimization design methods and priority design parameters of the classified sensors are presented. This research indicates that (1) strain transfer theory-based optimization design method is much suitable for the sensor that depends on the interfacial shear stress to transfer the deformation; (2) the priority design parameters are bonded (sensing) length, interfacial bonded strength, elastic modulus and radius of protective layer and thickness of adhesive layer; (3) the optimization design of sensors with two anchor pieces at two ends is independent of strain transfer theory as the strain transfer coefficient can be conveniently calibrated by test, and this kind of sensors has no obvious priority design parameters. Improved calibration test is put forward to enhance the accuracy of the calibration coefficient of end-expanding sensors. By considering the practical state of sensors and the testing accuracy, comprehensive and systematic analyses on optical fiber sensors are provided from the perspective of mechanical actions, which could scientifically instruct the application design and calibration test of industrialized optical fiber sensors.

Two phase modeling of nanofluid flow in existence of melting heat transfer by means of HAM

NASA Astrophysics Data System (ADS)

Sheikholeslami, M.; Jafaryar, M.; Bateni, K.; Ganji, D. D.

2018-02-01

In this article, Buongiorno Model is applied for investigation of nanofluid flow over a stretching plate in existence of magnetic field. Radiation and Melting heat transfer are taken into account. Homotopy analysis method (HAM) is selected to solve ODEs which are obtained from similarity transformation. Roles of Brownian motion, thermophoretic parameter, Hartmann number, porosity parameter, Melting parameter and Eckert number are presented graphically. Results indicate that nanofluid velocity and concentration enhance with rise of melting parameter. Nusselt number reduces with increase of porosity and melting parameters.

A Global 1 Degree by 1 Degree Distribution of Atmospheric/Soil CO2 Consumption by Continental Weathering and of Riverine HCO3 Yield (DB1012)

DOE Data Explorer

Suchet, Philippe Amiotte [Centre National de la Recherche Scientifique, Center de Geochimie de la Surface, Strasbourg Cedex, France; Probst, Jean-Lue [Centre National de la Recherche Scientifique, Center de Geochimie de la Surface, Strasbourg Cedex, France

1995-01-01

The mission of the Centre National de la Recherche Scientifique (CNRS) of Strasbourg Cedex, France is to study "The Global Carbon Cycle and its Perturbation by Man and Climate, the Terrestrial Biosphere". With the support of the Environment Programme of the European Communities, modeling of the spatial distribution of atmospheric-soil CO2 consumption by chemical weathering of continental rocks have been and are being conducted. One of the major results of these studies is a set of global maps which show the distribution of CO2 consumption (FCO2) and the transport of bicarbonate (FHCO3-) from rivers to the ocean, each in moles per kilometer squared per year (mol km2/yr). Continental weathering influences the geologic carbon cycle (Trabalka, 1985). The largest natural exchange fluxes of carbon occur between the atmosphere and the terrestrial biota, and between the atmosphere and the ocean surface waters (Houghton, et. al. 1990). River carbon input to the oceans is a component of the estimate of global air-sea CO2 fluxes (Sarminento and Sundquist 1992). It is estimated that about 0.3 gigatons of carbon per year (GtC/yr) are consumed by the chemical erosion of continental rocks and transferred as HCO3- to the oceans (Berner et. al. 1983; Meybeck 1987; and Probst 1992), while the flux of particulate and dissolved organic carbon transported by rivers to the oceans is estimated to be about 0.4 GtC/yr (Probst 1992). On the whole, about 0.7 GtC/yr are transferred by continental erosion from the soil-biosphere reservoir to the oceans. A model developed by Amiotte Suchet and Probst (1993) calculates the flux of atmospheric-soil CO2 consumed by the chemical erosion of continental rock (i.e., rock weathering) and the bicarbonate river transfer to the ocean. This model is based on a set of empirical relationships between FCO2 and the drainage (runoff) on the major rock types outcropping on the continents. The model assumes that the consumption of atmospheric CO2 by continental weathering is primarily influenced by drainage, and the different types of rocks outcropping the continents. This data base contains estimates of the net flux of atmospheric-soil CO2 (FCO2) produced by the Amiotte Suchet and Probst model and the associated bicarbonate river flux (FHCO3-). These variables are referenced to a 1 degree latitude by 1 degree longitude world grid. The grid contains 64,800 records (i.e. grid cells) originating at -180 degrees West longitude by -90 degrees North latitude, and extending to 180 degrees West longitude by 90 degrees North latitude.

Mechanistic insights on the responses of plant and ecosystem gas exchange to global environmental change: lessons from Biosphere 2.

PubMed

Gonzalez-Meler, Miquel A; Rucks, Jessica S; Aubanell, Gerard

2014-09-01

Scaling up leaf processes to canopy/ecosystem level fluxes is critical for examining feedbacks between vegetation and climate. Collectively, studies from Biosphere 2 Laboratory have provided important insight of leaf-to-ecosystem investigations of multiple environmental parameters that were not before possible in enclosed or field studies. B2L has been a testing lab for the applicability of new technologies such as spectral approaches to detect spatial and temporal changes in photosynthesis within canopies, or for the development of cavity ring-down isotope applications for ecosystem evapotranspiration. Short and long term changes in atmospheric CO2, drought or temperature allowed for intensive investigation of the interactions between photosynthesis and leaf, soil and ecosystem respiration. Experiments conducted in the rainforest biome have provided some of the most comprehensive dataset to date on the effects of climate change variables on tropical ecosystems. Results from these studies have been later corroborated in natural rainforest ecosystems and have improved the predictive capabilities of models that now show increased resilience of tropics to climate change. Studies of temperature and CO2 effects on ecosystem respiration and its leaf and soil components have helped reconsider the use of simple first-order kinetics for characterizing respiration in models. The B2L also provided opportunities to quantify the rhizosphere priming effect, or establish the relationships between net primary productivity, atmospheric CO2 and isoprene emissions. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Similarity of Mars and Mercury for terraforming and settling of people

NASA Astrophysics Data System (ADS)

Steklov, A. F.; Vidmachenko, A. P.

2018-05-01

We compared the main characteristics of the planets Mars and Mercury in the form normalized on the parameters of the planet Earth. Both planets turned out to be similar and close in terms of terraforming techniques, and conditions of comfortable human habitation in long term endo-planetary stations under the surface of a particular planetoid. Mars and Mercury also turned out to be similar on the vital activity of some other representatives of the Earth's biosphere. Our detailed analysis of the temperature distribution both over the entire surface of these planets, and in the conditions of their diurnal and annual variations on different latitudes and on Mars and on Mercury - showed that each of these planets has its advantages for the first terraforming.

Clouds, surface temperature, and the tropical and subtropical radiation budget

NASA Technical Reports Server (NTRS)

Dhuria, Harbans L.; Kyle, H. Lee

1980-01-01

Solar energy drives both the Earth's climate and biosphere, but the absorbed energy is unevenly distributed over the Earth. The tropical regions receive excess energy which is then transported by atmospheric and ocean currents to the higher latitudes. All regions at a given latitude receive the same top of the atmosphere solar irradiance (insolation). However, the net radiation received from the Sun in the tropics and subtropics varies greatly from one region to another depending on local conditions. Over land, variations in surface albedo are important. Over both land and ocean, surface temperature, cloud amount, and cloud type are also important. The Nimbus-7 cloud and Earth radiation budget (ERB) data sets are used to examine the affect of these parameters.

STUDY TO IDENTIFY IMPORTANT PARAMETERS FOR CHARACTERIZING PESTICIDE RESIDUE TRANSFER EFFICIENCIES

EPA Science Inventory

To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and non-dietary ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study to identify the important parameters for...

Estimation of whole lemon mass transfer parameters during hot air drying using different modelling methods

NASA Astrophysics Data System (ADS)

Torki-Harchegani, Mehdi; Ghanbarian, Davoud; Sadeghi, Morteza

2015-08-01

To design new dryers or improve existing drying equipments, accurate values of mass transfer parameters is of great importance. In this study, an experimental and theoretical investigation of drying whole lemons was carried out. The whole lemons were dried in a convective hot air dryer at different air temperatures (50, 60 and 75 °C) and a constant air velocity (1 m s-1). In theoretical consideration, three moisture transfer models including Dincer and Dost model, Bi- G correlation approach and conventional solution of Fick's second law of diffusion were used to determine moisture transfer parameters and predict dimensionless moisture content curves. The predicted results were then compared with the experimental data and the higher degree of prediction accuracy was achieved by the Dincer and Dost model.

Living Organisms Author Their Read-Write Genomes in Evolution

PubMed Central

2017-01-01

Evolutionary variations generating phenotypic adaptations and novel taxa resulted from complex cellular activities altering genome content and expression: (i) Symbiogenetic cell mergers producing the mitochondrion-bearing ancestor of eukaryotes and chloroplast-bearing ancestors of photosynthetic eukaryotes; (ii) interspecific hybridizations and genome doublings generating new species and adaptive radiations of higher plants and animals; and, (iii) interspecific horizontal DNA transfer encoding virtually all of the cellular functions between organisms and their viruses in all domains of life. Consequently, assuming that evolutionary processes occur in isolated genomes of individual species has become an unrealistic abstraction. Adaptive variations also involved natural genetic engineering of mobile DNA elements to rewire regulatory networks. In the most highly evolved organisms, biological complexity scales with “non-coding” DNA content more closely than with protein-coding capacity. Coincidentally, we have learned how so-called “non-coding” RNAs that are rich in repetitive mobile DNA sequences are key regulators of complex phenotypes. Both biotic and abiotic ecological challenges serve as triggers for episodes of elevated genome change. The intersections of cell activities, biosphere interactions, horizontal DNA transfers, and non-random Read-Write genome modifications by natural genetic engineering provide a rich molecular and biological foundation for understanding how ecological disruptions can stimulate productive, often abrupt, evolutionary transformations. PMID:29211049

Living Organisms Author Their Read-Write Genomes in Evolution.

PubMed

Shapiro, James A

2017-12-06

Evolutionary variations generating phenotypic adaptations and novel taxa resulted from complex cellular activities altering genome content and expression: (i) Symbiogenetic cell mergers producing the mitochondrion-bearing ancestor of eukaryotes and chloroplast-bearing ancestors of photosynthetic eukaryotes; (ii) interspecific hybridizations and genome doublings generating new species and adaptive radiations of higher plants and animals; and, (iii) interspecific horizontal DNA transfer encoding virtually all of the cellular functions between organisms and their viruses in all domains of life. Consequently, assuming that evolutionary processes occur in isolated genomes of individual species has become an unrealistic abstraction. Adaptive variations also involved natural genetic engineering of mobile DNA elements to rewire regulatory networks. In the most highly evolved organisms, biological complexity scales with "non-coding" DNA content more closely than with protein-coding capacity. Coincidentally, we have learned how so-called "non-coding" RNAs that are rich in repetitive mobile DNA sequences are key regulators of complex phenotypes. Both biotic and abiotic ecological challenges serve as triggers for episodes of elevated genome change. The intersections of cell activities, biosphere interactions, horizontal DNA transfers, and non-random Read-Write genome modifications by natural genetic engineering provide a rich molecular and biological foundation for understanding how ecological disruptions can stimulate productive, often abrupt, evolutionary transformations.

Interplay between solid Earth and biological evolution

NASA Astrophysics Data System (ADS)

Höning, Dennis; Spohn, Tilman

2017-04-01

Major shifts in Earth's evolution led to progressive adaptations of the biosphere. Particularly the emergence of continents permitted efficient use of solar energy. However, the widespread evolution of the biosphere fed back to the Earth system, often argued as a cause for the great oxidation event or as an important component in stabilizing Earth's climate. Furthermore, biologically enhanced weathering rates alter the flux of sediments in subduction zones, establishing a potential link to the deep interior. Stably bound water within subducting sediments not only enhances partial melting but further affects the mantle rheology. The mantle responds by enhancing its rates of convection, water outgassing, and subduction. How crucial is the emergence and evolution of life on Earth to these processes, and how would Earth have been evolved without the emergence of life? We here discuss concepts and present models addressing these questions and discuss the biosphere as a major component in evolving Earth system feedback cycles.

An extensive phase space for the potential martian biosphere.

PubMed

Jones, Eriita G; Lineweaver, Charles H; Clarke, Jonathan D

2011-12-01

We present a comprehensive model of martian pressure-temperature (P-T) phase space and compare it with that of Earth. Martian P-T conditions compatible with liquid water extend to a depth of ∼310 km. We use our phase space model of Mars and of terrestrial life to estimate the depths and extent of the water on Mars that is habitable for terrestrial life. We find an extensive overlap between inhabited terrestrial phase space and martian phase space. The lower martian surface temperatures and shallower martian geotherm suggest that, if there is a hot deep biosphere on Mars, it could extend 7 times deeper than the ∼5 km depth of the hot deep terrestrial biosphere in the crust inhabited by hyperthermophilic chemolithotrophs. This corresponds to ∼3.2% of the volume of present-day Mars being potentially habitable for terrestrial-like life.

The oxygen side of sulfate constrains global biospheric productivity in the mid-Phanerozoic

NASA Astrophysics Data System (ADS)

Wing, B. A.

2009-12-01

Recent work has read in the oxygen side of sulfate a record of CO2 concentrations and extreme environments on Neoproterozoic Earth [1, 2]. The connection between CO2 levels and total isotopic composition of mineral proxies for marine sulfate was motivated by an empirical correlation between CO2 concentrations and in 17O anomalies in samples of atmospheric gases preserved as bubbles in ice cores [3,4]. The 17O anomaly in atmospheric O2 has been interpreted to originate primarily from stratospheric photochemical cycles of O3, O2, and CO2 [3, 4]. Both CO2 and O3 form the 17O-enriched partners for the 17O-depleted O2 and, given a fixed atmospheric lifetime for O2, isotopic mass balance dictates that increasing CO2 levels will drive larger relative 17O deficits in O2. With a photochemically-calibrated relationship between the relative 17O anomaly in atmospheric O2 and atmospheric CO2 levels [1], the amount of CO2 in an ancient atmosphere can be directly estimated from the isotopic record of atmospheric O2 bound up in the oxygen side of sulfate. Although they are correlated, the relative 17O anomaly in atmospheric O2 is not only a function of atmospheric CO2 levels. Photosynthetic O2 is characterized by isotopically ‘normal’ oxygen sourced from the global hydrosphere [3]. Increased photosynthetic O2 production, therefore, dilutes the isotopic anomaly found in atmospheric O2. Measurements of the 17O anomaly in O2 from ice cores allow global changes in global biosphere productivity to be traced back to 60 ka ago [3, 4]. Applying similar analysis to recent datasets of the 17O anomaly in marine sulfates [1] and atmospheric CO2 levels [5] produces quantitative global biospheric productivity estimates for the time interval from 310 to 240 Ma ago. Although the time resolution is coarse, much of the mid-Phanerozoic was characterized by global biospheric productivity similar in magnitude to the average global biospheric productivity for the last 10 ka. Counterintuitively, this includes the global mid-Carboniferous biosphere. Global biospheric productivity at the end of the Permian, however, was apparently greatly enhanced relative to the rest of the mid-Phanerozoic. [1] Huiming Bao, J. Lyons, Chuanming Zhou (2008) Nature 453 504. [2] Huiming Bao, I.J. Fairchild, P.M. Wynn, C. Spötl (2009) Science 323 119. [3] B. Luz, E. Barkan, M. L. Bender, M. H. Thiemens, K. A. Boering (1999) Nature 400 547. [4] T. Blunier, B. Barnett, M. L. Bender, M. B. Hendricks (2002) Global Biogeochem. Cycles 16 doi:10.1029/2001GB001460. [5] D. L. Royer (2006) Geochim. Cosmochim. Acta 70 5665.

Heat and water rate transfer processes in the human respiratory tract at various altitudes.

PubMed

Kandjov, I M

2001-02-01

The process of the respiratory air conditioning as a process of heat and mass exchange at the interface inspired air-airways surface was studied. Using a model of airways (Olson et al., 1970) where the segments of the respiratory tract are like cylinders with a fixed length and diameter, the corresponding heat transfer equations, in the paper are founded basic rate exchange parameters-convective heat transfer coefficient h(c)(W m(-2) degrees C(-1)) and evaporative heat transfer coefficient h(e)(W m(-2)hPa(-1)). The rate transfer parameters assumed as sources with known heat power are connected to airflow rate in different airways segments. Relationships expressing warming rate of inspired air due to convection, warming rate of inspired air due to evaporation, water diffused in the inspired air from the airways wall, i.e. a system of air conditioning parameters, was composed. The altitude dynamics of the relations is studied. Every rate conditioning parameter is an increasing function of altitude. The process of diffusion in the peripheral bronchial generations as a basic transfer process is analysed. The following phenomenon is in effect: the diffusion coefficient increases with altitude and causes a compensation of simultaneous decreasing of O(2)and CO(2)densities in atmospheric air. Due to this compensation, the diffusion in the peripheral generations with altitude is approximately constant. The elements of the human anatomy optimality as well as the established dynamics are discussed and assumed. The square form of the airways after the trachea expressed in terms of transfer supposes (in view of maximum contact surface), that a maximum heat and water exchange is achieved, i.e. high degree of air condition at fixed environmental parameters and respiration regime. Copyright 2001 Academic Press.

Typecasting catchments: Classification, directionality, and the pursuit of universality

NASA Astrophysics Data System (ADS)

Smith, Tyler; Marshall, Lucy; McGlynn, Brian

2018-02-01

Catchment classification poses a significant challenge to hydrology and hydrologic modeling, restricting widespread transfer of knowledge from well-studied sites. The identification of important physical, climatological, or hydrologic attributes (to varying degrees depending on application/data availability) has traditionally been the focus for catchment classification. Classification approaches are regularly assessed with regard to their ability to provide suitable hydrologic predictions - commonly by transferring fitted hydrologic parameters at a data-rich catchment to a data-poor catchment deemed similar by the classification. While such approaches to hydrology's grand challenges are intuitive, they often ignore the most uncertain aspect of the process - the model itself. We explore catchment classification and parameter transferability and the concept of universal donor/acceptor catchments. We identify the implications of the assumption that the transfer of parameters between "similar" catchments is reciprocal (i.e., non-directional). These concepts are considered through three case studies situated across multiple gradients that include model complexity, process description, and site characteristics. Case study results highlight that some catchments are more successfully used as donor catchments and others are better suited as acceptor catchments. These results were observed for both black-box and process consistent hydrologic models, as well as for differing levels of catchment similarity. Therefore, we suggest that similarity does not adequately satisfy the underlying assumptions being made in parameter regionalization approaches regardless of model appropriateness. Furthermore, we suggest that the directionality of parameter transfer is an important factor in determining the success of parameter regionalization approaches.

Multiple solutions in MHD flow and heat transfer of Sisko fluid containing nanoparticles migration with a convective boundary condition: Critical points

NASA Astrophysics Data System (ADS)

Dhanai, Ruchika; Rana, Puneet; Kumar, Lokendra

2016-05-01

The motivation behind the present analysis is to focus on magneto-hydrodynamic flow and heat transfer characteristics of non-Newtonian fluid (Sisko fluid) past a permeable nonlinear shrinking sheet utilizing nanoparticles involving convective boundary condition. The non-homogenous nanofluid transport model considering the effect of Brownian motion, thermophoresis, suction/injection and no nanoparticle flux at the sheet with convective boundary condition has been solved numerically by the RKF45 method with shooting technique. Critical points for various pertinent parameters are evaluated in this study. The dual solutions (both first and second solutions) are captured in certain range of material constant (nc< n < ∞) , mass transfer parameter (sc < s < ∞) and shrinking parameter (χc < χ < 0) . For both the branches (upper and lower branch), the rate of heat transfer is an increasing function of the power-law index, Prandtl number and Biot number, whereas it is a decreasing function of the material constant and thermophoresis parameter.

Parameter Estimation of Actuators for Benchmark Active Control Technology (BACT) Wind Tunnel Model with Analysis of Wear and Aerodynamic Loading Effects

NASA Technical Reports Server (NTRS)

Waszak, Martin R.; Fung, Jimmy

1998-01-01

This report describes the development of transfer function models for the trailing-edge and upper and lower spoiler actuators of the Benchmark Active Control Technology (BACT) wind tunnel model for application to control system analysis and design. A simple nonlinear least-squares parameter estimation approach is applied to determine transfer function parameters from frequency response data. Unconstrained quasi-Newton minimization of weighted frequency response error was employed to estimate the transfer function parameters. An analysis of the behavior of the actuators over time to assess the effects of wear and aerodynamic load by using the transfer function models is also presented. The frequency responses indicate consistent actuator behavior throughout the wind tunnel test and only slight degradation in effectiveness due to aerodynamic hinge loading. The resulting actuator models have been used in design, analysis, and simulation of controllers for the BACT to successfully suppress flutter over a wide range of conditions.

The Aggregate Description of Semi-Arid Vegetation with Precipitation-Generated Soil Moisture Heterogeneity

NASA Technical Reports Server (NTRS)

White, Cary B.; Houser, Paul R.; Arain, Altaf M.; Yang, Zong-Liang; Syed, Kamran; Shuttleworth, W. James

1997-01-01

Meteorological measurements in the Walnut Gulch catchment in Arizona were used to synthesize a distributed, hourly-average time series of data across a 26.9 by 12.5 km area with a grid resolution of 480 m for a continuous 18-month period which included two seasons of monsoonal rainfall. Coupled surface-atmosphere model runs established the acceptability (for modelling purposes) of assuming uniformity in all meteorological variables other than rainfall. Rainfall was interpolated onto the grid from an array of 82 recording rain gauges. These meteorological data were used as forcing variables for an equivalent array of stand-alone Biosphere-Atmosphere Transfer Scheme (BATS) models to describe the evolution of soil moisture and surface energy fluxes in response to the prevalent, heterogeneous pattern of convective precipitation. The calculated area-average behaviour was compared with that given by a single aggregate BATS simulation forced with area-average meteorological data. Heterogeneous rainfall gives rise to significant but partly compensating differences in the transpiration and the intercepted rainfall components of total evaporation during rain storms. However, the calculated area-average surface energy fluxes given by the two simulations in rain-free conditions with strong heterogeneity in soil moisture were always close to identical, a result which is independent of whether default or site-specific vegetation and soil parameters were used. Because the spatial variability in soil moisture throughout the catchment has the same order of magnitude as the amount of rain failing in a typical convective storm (commonly 10% of the vegetation's root zone saturation) in a semi-arid environment, non-linearitv in the relationship between transpiration and the soil moisture available to the vegetation has limited influence on area-average surface fluxes.

A computational study of entropy generation in magnetohydrodynamic flow and heat transfer over an unsteady stretching permeable sheet

NASA Astrophysics Data System (ADS)

Saeed Butt, Adnan; Ali, Asif

2014-01-01

The present article aims to investigate the entropy effects in magnetohydrodynamic flow and heat transfer over an unsteady permeable stretching surface. The time-dependent partial differential equations are converted into non-linear ordinary differential equations by suitable similarity transformations. The solutions of these equations are computed analytically by the Homotopy Analysis Method (HAM) then solved numerically by the MATLAB built-in routine. Comparison of the obtained results is made with the existing literature under limiting cases to validate our study. The effects of unsteadiness parameter, magnetic field parameter, suction/injection parameter, Prandtl number, group parameter and Reynolds number on flow and heat transfer characteristics are checked and analysed with the aid of graphs and tables. Moreover, the effects of these parameters on entropy generation number and Bejan number are also shown graphically. It is examined that the unsteadiness and presence of magnetic field augments the entropy production.

Ocean Drilling Program Contributions to the Understanding of the Deep Subsurface Biosphere

NASA Astrophysics Data System (ADS)

Fisk, M. R.

2003-12-01

Tantalizing evidence for microbes in oceanic basalts has been reported for a few decades, but it was from rocks cored on Ocean Drilling Program (ODP) Leg 148 in 1993 that the first clear-cut evidence of microbial invasion of ocean basalts was obtained. (Work on ODP legs, starting with Leg 112 in 1986, had already revealed the presence of significant microbial biomass in sediments.) In 1997 ODP created the Deep Biosphere Program Planning Group to promote the investigation of the microbiology of the ocean crust. In 1999 ODP built a microbiology lab on the JOIDES Resolution, and used the lab that year (Legs 185 and 187) to test the amount of microbial contamination introduced into rocks during drilling and to establish cultures from cored basalts. These experiments have been repeated on several legs since then. The development of CORKs has permitted long-term sampling of subseafloor fluids, and microorganisms have been recovered from CORKed holes. Thus, ODP made it possible for the scientific community to address major questions about the biology of the igneous crust, such as, (1) What microbes are present? (2) How abundant are they? (3) How are they distributed? DNA from basalts and subseafloor fluids reveal what types of organisms are present. Cell abundance and biomass have been estimated based on cell counts and on organic content of basalts. Surveys of basalts in DSDP/ODP repositories indicate that microorganisms are ubiquitous in the igneous crust. Microorganisms are found in rocks that are close to 100° C. They are found as deep as 1500 m below the sea floor, and in rocks as young as a few years and as old as 170 million years. Because of the vast size of the habitat, microorganism, even if present in small numbers, could be a significant fraction of the Earth's biomass. In a short time ODP contributed to advances in our understanding of the oceanic subsurface biosphere. Answers to other significant questions such as: (1) How do the microorganisms live?, (2) What impact do subsurface microorganisms have on the surface biosphere? (3) And, what roles do the subsurface biosphere play in element cycling? will be answered by future drilling. The International Ocean Drilling Program (IODP) is in the enviable position of providing support to address these key questions about the Earth's subsurface biosphere.

Modern Microbial Ecosystems are a Key to Understanding Our Biosphere's Early Evolution and its Contributions To The Atmosphere and Rock Record

NASA Technical Reports Server (NTRS)

DesMarais, David J.; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

The survival of our early biosphere depended upon efficient coordination anion- diverse microbial populations. Microbial mats exhibit a 3.46-billion-year fossil record, thus they are the oldest known ecosystems. Photosynthetic microbial mats were key because, today, sunlight powers more than 99 percent of global primary productivity. Thus photosynthetic ecosystems have affected the atmosphere profoundly and have created the most pervasive, easily-detected fossils. Photosynthetic biospheres elsewhere will be most detectible via telescopes or spacecraft. As a part of the Astrobiology Institute, our Ames Microbial Ecosystems group examines the roles played by ecological processes in the early evolution of our biosphere, as recorded in geologic fossils and in the macromolecules of living cells: (1) We are defining the microbial mat microenvironment, which was an important milieu for early evolution. (2) We are comparing mats in contrasting environments to discern strategies of adaptation and diversification, traits that were key for long-term survival. (3) We have selected sites that mimic key environmental attributes of early Earth and thereby focus upon evolutionary adaptations to long-term changes in the global environment. (4) Our studies of gas exchange contribute to better estimates of biogenic gases in Earth's early atmosphere. This group therefore directly addresses the question: How have the Earth and its biosphere influenced each other over time Our studies strengthen the systematics for interpreting the microbial fossil record and thereby enhance astrobiological studies of martian samples. Our models of biogenic gas emissions will enhance models of atmospheres that might be detected on inhabited extrasolar planets. This work therefore also addresses the question: How can other biospheres be recogniZed" Our choice of field sites helps us explore Earth's evolving early environment. For example, modern mats that occupy thermal springs and certain freshwater environments experience conditions such as low O2 and sulfate and high inorganic carbon and sulfide levels that resemble those of ancient marine environments. Later in history, both biologically-induced carbonate precipitation and the trapping and binding of suspended grains of carbonate became a dominant mechanism for carbonate deposition. Modern marine carbonate platforms and alkaline offer good examples of microbiologically-induced calcification. Both marine platforms and solar salterns illustrate microbially-driven trapping and binding. We are also exploring the effects of water composition upon the exchange of biogenic gases with the atmosphere.

Interrogation of electrical connector faults using miniaturized UWB sources

NASA Astrophysics Data System (ADS)

Tokgöz, Çaǧata; Dardona, Sameh

2017-01-01

A diagnostic method for the detection, identification, and characterization of precursors of faults due to partial insertion of pin-socket contacts within electrical connectors commonly used in avionics systems is presented. It is demonstrated that a miniaturized ultrawideband (UWB) source and a minispectrum analyzer can be employed to measure resonant frequency shifts in connector S parameters as a small and low-cost alternative to a large and expensive network analyzer. The transfer function of an electrical connector is represented as a ratio of the spectra measured using the spectrum analyzer with and without the connector. Alternatively, the transfer function is derived in terms of the connector S parameters and the reflection coefficients at both ports of the connector. The transfer function data obtained using this derivation agreed well with its representation as a measured spectral ratio. The derivation enabled the extraction of the connector S parameters from the measured transfer function data as a function of the insertion depth of a pin-socket contact within the connector. In comparison with the S parameters measured directly using a network analyzer at multiple insertion depths, the S parameters extracted from the measured transfer function showed consistent and reliable representation of the electrical connector fault. The results demonstrate the potential of integrating a low-cost miniaturized UWB device into a connector harness for real-time detection of precursors to partially inserted connector faults.

Space Transfer Concepts and Analyses for Exploration Missions. Technical Directive 12: Beamed Power Systems Study

NASA Technical Reports Server (NTRS)

Eder, D.

1992-01-01

Parametric models were constructed for Earth-based laser powered electric orbit transfer from low Earth orbit to geosynchronous orbit. These models were used to carry out performance, cost/benefit, and sensitivity analyses of laser-powered transfer systems including end-to-end life cycle cost analyses for complete systems. Comparisons with conventional orbit transfer systems were made indicating large potential cost savings for laser-powered transfer. Approximate optimization was done to determine best parameter values for the systems. Orbit transfer flights simulations were conducted to explore effects of parameters not practical to model with a spreadsheet. The simulations considered view factors that determine when power can be transferred from ground stations to an orbit transfer vehicle and conducted sensitivity analyses for numbers of ground stations, Isp including dual-Isp transfers, and plane change profiles. Optimal steering laws were used for simultaneous altitude and plane change. Viewing geometry and low-thrust orbit raising were simultaneously simulated. A very preliminary investigation of relay mirrors was made.

Correlation of laboratory and production freeze drying cycles.

PubMed

Kuu, Wei Y; Hardwick, Lisa M; Akers, Michael J

2005-09-30

The purpose of this study was to develop the correlation of cycle parameters between a laboratory and a production freeze-dryer. With the established correlation, key cycle parameters obtained using a laboratory dryer may be converted to those for a production dryer with minimal experimental efforts. In order to develop the correlation, it was important to consider the contributions from the following freeze-drying components: (1) the dryer, (2) the vial, and (3) the formulation. The critical parameters for the dryer are the shelf heat transfer coefficient and shelf surface radiation emissivity. The critical parameters for the vial are the vial bottom heat transfer coefficients (the contact parameter Kcs and separation distance lv), and vial top heat transfer coefficient. The critical parameter of the formulation is the dry layer mass transfer coefficient. The above heat and mass transfer coefficients were determined by freeze-drying experiments in conjunction with mathematical modeling. With the obtained heat and mass transfer coefficients, the maximum product temperature, Tbmax, during primary drying was simulated using a primary drying subroutine as a function of the shelf temperature and chamber pressure. The required shelf temperature and chamber pressure, in order to perform a successful cycle run without product collapse, were then simulated based on the resulting values of Tbmax. The established correlation approach was demonstrated by the primary drying of the model formulation 5% mannitol solution. The cycle runs were performed using a LyoStar dryer as the laboratory dryer and a BOC Edwards dryer as the production dryer. The determined normalized dried layer mass transfer resistance for 5% mannitol is expressed as RpN=0.7313+17.19l, where l is the receding dry layer thickness. After demonstrating the correlation approach using the model formulation 5% mannitol, a practical comparison study was performed for the actual product, the lactate dehydrogenase (LDH) formulation. The determined normalized dried layer mass transfer resistance for the LDH formulation is expressed as RpN=4.344+10.85l. The operational templates Tbmax and primary drying time were also generated by simulation. The cycle run for the LDH formulation using the Edwards production dryer verified that the cycle developed in a laboratory freeze-dryer was transferable at the production scale.

Design of the transfer line from booster to storage ring at 3 GeV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bayar, C., E-mail: cafer.bayar@cern.ch; Ciftci, A. K., E-mail: abbas.kenan.ciftci@cern.ch

The Synchrotron Booster Ring accelerates the e-beam up to 3 GeV and particles are transported from booster to storage ring by transfer line. In this study, two options are considered, the first one is a long booster which shares the same tunnel with storage ring and the second one is a compact booster. As a result, two transfer line are designed based on booster options. The optical design is constrained by the e-beam Twiss parameters entering and leaving the transfer line. Twiss parameters in the extraction point of booster are used for the entrance of transfer line and are matchedmore » in the exit of transfer line to the injection point of the storage ring.« less

USSR and Eastern Europe Scientific Abstracts. Geophysics, Astronomy and Space, Number 430

DTIC Science & Technology

1978-10-02

making the necessary preparations. (PRAVDA 30 Aug 78 p 1) 30 AUGUST 31 AUGUST In accordance with the " Biosfera " (biosphere) experiment, the...On their sixth day on board the space complex, cosmonauts Bykovskiy and Jaehn continued the " Biosfera " environmental studies experiment as well as...AUGUST In accordance with the " Biosfera " (biosphere) experiment, the internatxonal crew conducted observations of the earth’s surface, a variety of

Our Changing Planet: The U.S. Climate Change Science Program for Fiscal Year 2009

DTIC Science & Technology

2008-07-01

forests of the southern Yucatan Peninsula form the largest expanse of this ecosystem type remaining in Mexico. It forms an ecocline between a drier...Calakmul Biosphere Reserve to preserve this unique forested area. The Southern Yucatan Peninsular Region Project is currently engaged in an assessment of the...Eastman, B.L. Turner II, S. Calme, R. Dickson, C. Pozo, and F. Sangermano, 2007: Land Change in the southern Yucatan and Calamul biosphere reserve

Improved Carbon Flux Observations over Urban Areas Using Carbonyl Sulfide (COS) to Differentiate Contributions from Biosphere

NASA Astrophysics Data System (ADS)

Whelan, M.; LaFranchi, B. W.; Bambha, R.; Michelsen, H. A.; Fischer, M. L.; Graven, H. D.; Baker, I. T.; Guilderson, T.; Campbell, J. E.

2016-12-01

Direct measurement and attribution of carbon exchange over urban areas is challenging because of the heterogeneity of the landscape and errors introduced by flux source partitioning. One important contribution to uncertainty is the influence of the urban biosphere on the regional carbon budget. Atmospheric observations of carbonyl sulfide (COS) are an emerging tool for estimating gross primary productivity: COS is consumed in plant leaves by parallel pathways to CO2 uptake, without the additional complexity of an analogous respiration term. This study makes use of COS measurements to better understand fluctuations in total CO2 concentrations over an urban region due to the balance of photosynthesis and respiration. In situ ground-based observations of trace gas concentrations were made from a tower in Livermore, CA, USA, and interpreted with WRF-STILT back trajectories and gridded data sets (e.g. VULCAN, a new anthropogenic COS inventory), supplemented with biosphere models (SiB, CASA-GFED3). CO2, 14CO2, and CO observations were used to first parse the contribution of fossil fuel emissions to total CO2. Changes in the remainder CO2 was differentiated as the sum of biosphere components with associated uncertainties. This approach could be used to better validate carbon emissions reduction measures and ecosytem-based carbon capture projects on the regional scale.

Multiple greenhouse-gas feedbacks from the land biosphere under future climate change scenarios

NASA Astrophysics Data System (ADS)

Stocker, Benjamin D.; Roth, Raphael; Joos, Fortunat; Spahni, Renato; Steinacher, Marco; Zaehle, Soenke; Bouwman, Lex; Xu-Ri; Prentice, Iain Colin

2013-07-01

Atmospheric concentrations of the three important greenhouse gases (GHGs) CO2, CH4 and N2O are mediated by processes in the terrestrial biosphere that are sensitive to climate and CO2. This leads to feedbacks between climate and land and has contributed to the sharp rise in atmospheric GHG concentrations since pre-industrial times. Here, we apply a process-based model to reproduce the historical atmospheric N2O and CH4 budgets within their uncertainties and apply future scenarios for climate, land-use change and reactive nitrogen (Nr) inputs to investigate future GHG emissions and their feedbacks with climate in a consistent and comprehensive framework. Results suggest that in a business-as-usual scenario, terrestrial N2O and CH4 emissions increase by 80 and 45%, respectively, and the land becomes a net source of C by AD 2100. N2O and CH4 feedbacks imply an additional warming of 0.4-0.5°C by AD 2300; on top of 0.8-1.0°C caused by terrestrial carbon cycle and Albedo feedbacks. The land biosphere represents an increasingly positive feedback to anthropogenic climate change and amplifies equilibrium climate sensitivity by 22-27%. Strong mitigation limits the increase of terrestrial GHG emissions and prevents the land biosphere from acting as an increasingly strong amplifier to anthropogenic climate change.

[The high pressure life of piezophiles].

PubMed

Oger, Philippe; Cario, Anaïs

2014-01-01

The deep biosphere is composed of very different biotopes located in the depth of the oceans, the ocean crust or the lithosphere. Although very different, deep biosphere biotopes share one common feature, high hydrostatic pressure. The deep biosphere is colonized by specific organisms, called piezophiles, that are able to grow under high hydrostatic pressure. Bacterial piezophiles are mainly psychrophiles belonging to five genera of γ-proteobacteria, Photobacterium, Shewanella, Colwellia, Psychromonas and Moritella, while piezophilic Archaea are mostly (hyper)thermophiles from the Thermococcales. None of these genera are specific for the deep biosphere. High pressure deeply impacts the activity of cells and cellular components, and reduces the activity of numerous key processes, eventually leading to cell death of piezosensitive organisms. Biochemical and genomic studies yield a fragmented view on the adaptive mechanisms in piezophiles. It is yet unclear whether piezophilic adaptation requires the modification of a few genes, or metabolic pathways, or a more profound reorganization of the genome, the fine tuning of gene expression to compensate the pressure-induced loss of activity of the proteins most affected by high pressure, or a stress-like physiological cell response. In contrast to what has been seen for thermophily or halophily, the adaptation to high pressure is diffuse in the genome and may concern only a small fraction of the genes. © Société de Biologie, 2014.

Constraining Centennial-Scale Ecosystem-Climate Interactions with a Pre-colonial Forest Reconstruction across the Upper Midwest and Northeastern United States

NASA Astrophysics Data System (ADS)

Matthes, J. H.; Dietze, M.; Fox, A. M.; Goring, S. J.; McLachlan, J. S.; Moore, D. J.; Poulter, B.; Quaife, T. L.; Schaefer, K. M.; Steinkamp, J.; Williams, J. W.

2014-12-01

Interactions between ecological systems and the atmosphere are the result of dynamic processes with system memories that persist from seconds to centuries. Adequately capturing long-term biosphere-atmosphere exchange within earth system models (ESMs) requires an accurate representation of changes in plant functional types (PFTs) through time and space, particularly at timescales associated with ecological succession. However, most model parameterization and development has occurred using datasets than span less than a decade. We tested the ability of ESMs to capture the ecological dynamics observed in paleoecological and historical data spanning the last millennium. Focusing on an area from the Upper Midwest to New England, we examined differences in the magnitude and spatial pattern of PFT distributions and ecotones between historic datasets and the CMIP5 inter-comparison project's large-scale ESMs. We then conducted a 1000-year model inter-comparison using six state-of-the-art biosphere models at sites that bridged regional temperature and precipitation gradients. The distribution of ecosystem characteristics in modeled climate space reveals widely disparate relationships between modeled climate and vegetation that led to large differences in long-term biosphere-atmosphere fluxes for this region. Model simulations revealed that both the interaction between climate and vegetation and the representation of ecosystem dynamics within models were important controls on biosphere-atmosphere exchange.

Impact craters as biospheric microenvironments, Lawn Hill Structure, Northern Australia.

PubMed

Lindsay, John; Brasier, Martin

2006-04-01

Impact craters on Mars act as traps for eolian sediment and in the past may have provided suitable microenvironments that could have supported and preserved a stressed biosphere. If this is so, terrestrial impact structures such as the 18-km-diameter Lawn Hill Structure, in northern Australia, may prove useful as martian analogs. We sampled outcrop and drill core from the carbonate fill of the Lawn Hill Structure and recorded its gamma-log signature. Facies data along with whole rock geochemistry and stable isotope signatures show that the crater fill is an outlier of the Georgina Basin and was formed by impact at, or shortly before, approximately 509-506 million years ago. Subsequently, it was rapidly engulfed by the Middle Cambrian marine transgression, which filled it with shallow marine carbonates and evaporites. The crater formed a protected but restricted microenvironment in which sediments four times the thickness of the nearby basinal succession accumulated. Similar structures, common on the martian surface, may well have acted as biospheric refuges as the planet's water resources declined. Low-pH aqueous environments on Earth similar to those on Mars, while extreme, support diverse ecologies. The architecture of the eolian crater fill would have been defined by long-term ground water cycles resulting from intermittent precipitation in an extremely arid climate. Nutrient recycling, critical to a closed lacustrine sub-ice biosphere, could be provided by eolian transport onto the frozen water surface.

Predicting what extra-terrestrials will be like: and preparing for the worst.

PubMed

Morris, Simon Conway

2011-02-13

It is difficult to imagine evolution in alien biospheres operating in any manner other than Darwinian. Yet, it is also widely assumed that alien life-forms will be just that: strange, un-nerving and probably repulsive. There are two reasons for this view. First, it is assumed that the range of habitable environments available to extra-terrestrial life is far wider than on Earth. I suggest, however, that terrestrial life is close to the physical and chemical limits of life anywhere. Second, it is a neo-Darwinian orthodoxy that evolution lacks predictability; imagining what extra-terrestrial life would look like in any detail is a futile exercise. To the contrary, I suggest that the outcomes of evolution are remarkably predictable. This, however, leads us to consider two opposites, both of which should make our blood run cold. The first, and actually extremely unlikely, is that alien biospheres will be strikingly similar to our terrestrial equivalent and that in such biospheres intelligence will inevitably emerge. The reasons for this revolve around the ubiquity of evolutionary convergence, the determinate structure of the Tree of Life and molecular inherency. But if something like a human is an inevitability, why do I also claim that the first possibility is 'extremely unlikely'? Simply because the other possibility is actually the correct answer. Paradoxically, we and our biosphere are completely alone. So which is worse? Meeting ourselves or meeting nobody?

Chemical reaction for Carreau-Yasuda nanofluid flow past a nonlinear stretching sheet considering Joule heating

NASA Astrophysics Data System (ADS)

Khan, Mair; Shahid, Amna; Malik, M. Y.; Salahuddin, T.

2018-03-01

Current analysis has been made to scrutinize the consequences of chemical response against magneto-hydrodynamic Carreau-Yasuda nanofluid flow induced by a non-linear stretching surface considering zero normal flux, slip and convective boundary conditions. Joule heating effect is also considered. Appropriate similarity approach is used to convert leading system of PDE's for Carreau-Yasuda nanofluid into nonlinear ODE's. Well known mathematical scheme namely shooting method is utilized to solve the system numerically. Physical parameters, namely Weissenberg number We , thermal slip parameter δ , thermophoresis number NT, non-linear stretching parameter n, magnetic field parameter M, velocity slip parameter k , Lewis number Le, Brownian motion parameter NB, Prandtl number Pr, Eckert number Ec and chemical reaction parameter γ upon temperature, velocity and concentration profiles are visualized through graphs and tables. Numerical influence of mass and heat transfer rates and friction factor are also represented in tabular as well as graphical form respectively. Skin friction coefficient reduces when Weissenberg number We is incremented. Rate of heat transfer enhances for large values of Brownian motion constraint NB. By increasing Lewis quantity Le rate of mass transfer declines.

Heat and mass transfer in MHD free convection from a moving permeable vertical surface by a perturbation technique

NASA Astrophysics Data System (ADS)

Abdelkhalek, M. M.

2009-05-01

Numerical results are presented for heat and mass transfer effect on hydromagnetic flow of a moving permeable vertical surface. An analysis is performed to study the momentum, heat and mass transfer characteristics of MHD natural convection flow over a moving permeable surface. The surface is maintained at linear temperature and concentration variations. The non-linear coupled boundary layer equations were transformed and the resulting ordinary differential equations were solved by perturbation technique [Aziz A, Na TY. Perturbation methods in heat transfer. Berlin: Springer-Verlag; 1984. p. 1-184; Kennet Cramer R, Shih-I Pai. Magneto fluid dynamics for engineers and applied physicists 1973;166-7]. The solution is found to be dependent on several governing parameter, including the magnetic field strength parameter, Prandtl number, Schmidt number, buoyancy ratio and suction/blowing parameter, a parametric study of all the governing parameters is carried out and representative results are illustrated to reveal a typical tendency of the solutions. Numerical results for the dimensionless velocity profiles, the temperature profiles, the concentration profiles, the local friction coefficient and the local Nusselt number are presented for various combinations of parameters.

Developing Starlight connections with UNESCO sites through the Biosphere Smart

NASA Astrophysics Data System (ADS)

Marin, Cipriano

2015-08-01

The large number of UNESCO Sites around the world, in outstanding sites ranging from small islands to cities, makes it possible to build and share a comprehensive knowledge base on good practices and policies on the preservation of the night skies consistent with the protection of the associated scientific, natural and cultural values. In this context, the Starlight Initiative and other organizations such as IDA play a catalytic role in an essential international process to promote comprehensive, holistic approaches on dark sky preservation, astronomical observation, environmental protection, responsible lighting, sustainable energy, climate change and global sustainability.Many of these places have the potential to become models of excellence to foster the recovery of the dark skies and its defence against light pollution, included some case studies mentioned in the Portal to the Heritage of Astronomy.Fighting light pollution and recovering starry sky are already elements of a new emerging culture in biosphere reserves and world heritage sites committed to acting on climate change and sustainable development. Over thirty territories, including biosphere reserves and world heritage sites, have been developed successful initiatives to ensure night sky quality and promote sustainable lighting. Clear night skies also provide sustainable income opportunities as tourists and visitors are eagerly looking for sites with impressive night skies.Taking into account the high visibility and the ability of UNESCO sites to replicate network experiences, the Starlight Initiative has launched an action In cooperation with Biosphere Smart, aimed at promoting the Benchmark sites.Biosphere Smart is a global observatory created in partnership with UNESCO MaB Programme to share good practices, and experiences among UNESCO sites. The Benchmark sites window allows access to all the information of the most relevant astronomical heritage sites, dark sky protected areas and other places committed to the preservation of the values associated with the night sky. A new step ahead in our common task of protecting the starry skies at UNESCO sites.

Multilevel approach to mentoring in the Research Experiences for Undergraduates programs

NASA Astrophysics Data System (ADS)

Bonine, K. E.; Dontsova, K.; Pavao-Zuckerman, M.; Paavo, B.; Hogan, D.; Oberg, E.; Gay, J.

2015-12-01

This presentation focuses on different types of mentoring for students participating in Research Experiences for Undergraduates programs with examples, including some new approaches, from The Environmental and Earth Systems Research Experiences for Undergraduates Program at Biosphere 2. While traditional faculty mentors play essential role in students' development as researchers and professionals, other formal and informal mentoring can be important component of the REU program and student experiences. Students receive mentoring from program directors, coordinators, and on site undergraduate advisors. While working on their research projects, REU students receive essential support and mentoring from undergraduate and graduate students and postdoctoral scientists in the research groups of their primary mentors. Cohort living and group activities give multiple opportunities for peer mentoring where each student brings their own strengths and experiences to the group. Biosphere 2 REU program puts strong emphasis on teaching students to effectively communicate their research to public. In order to help REUs learn needed skills the outreach personnel at Biosphere 2 mentor and advise students both in groups and individually, in lecture format and by personal example, on best outreach approaches in general and on individual outreach projects students develop. To further enhance and strengthen outreach mentoring we used a novel approach of blending cohort of REU students with the Cal Poly STAR (STEM Teacher And Researcher) Program fellows, future K-12 STEM teachers who are gaining research experience at Biosphere 2. STAR fellows live together with the REU students and participate with them in professional development activities, as well as perform research side by side. Educational background and experiences gives these students a different view and better preparation and tools to effectively communicate and adapt science to lay audiences, a challenge commonly facing researchers but rarely taught to future scientists. In addition, REU students act as mentors themselves to the middle and high school students in Biosphere 2 Science Academy sharing with them exciting research they are doing and their experiences about doing science and life in college.

What are the Outstanding Questions in Biosphere-Atmosphere Exchange?

NASA Astrophysics Data System (ADS)

Katul, G.; Finnigan, J.

2002-12-01

Our answer to this question has three parts. At the highest level human population is now so large (and will grow to 10-12 million by 2050 before stabilizing and reversing) and our capacity to influence the biosphere is so profound that we must now treat human, biophysical and geophysical processes as a single interacting system: the Anthroposphere. The Anthroposphere is a complex adaptive system (CAS) in the sense that action of humans individually or in groups (as large as nations) are a response to an environment that includes not just the geosphere and biosphere but the sum of human interactions as well. These actions, in turn, will change this system that provides critical ecosystem services that we are just now realizing are finite and threatened. At present we lack the tools and understanding even to frame key questions about the Anthroposphere although the emerging discipline of Complex System Science is hinting at ways this might be done. At the next level we address the problems posed by cross-scale interactions central to the state and function of the geosphere and biosphere, where processes at the cellular level, (e.g. photosynthesis and respiration), have consequences on the global level and vice-versa through a sequence of non-linear upscale and downscale interactions. Currently there are large gaps in our understanding of this scale cascade that inhibit our ability to parameterize, model and predict phenomena such as the rapid shifts in climate that recent studies of the paleo record have revealed. In short, we need to quantify the risk that our current actions may cause abrupt climate changes that may then feed upon the Anthrosphere. Unless we can reduce the uncertainty with which we describe quantitatively the non-human parts of the Anthroposphere, the injection of models of human interaction, initially tentative, may reduce our predictive ability to unusable levels. Finally we can detail a set of key processes that are themselves critical to geosphere-biosphere functioning but which are poorly understood as yet.

Top-Down Assessment of the Asian Carbon Budget Since the Mid 1990s

NASA Astrophysics Data System (ADS)

Thompson, R.; Canadell, J.; Patra, P. K.; Chevallier, F.; Maksyutov, S. S.; Law, R. M.; Ziehn, T.; van der Laan-Luijkx, I. T.; Peters, W.; Ganshin, A.; Zhuravlev, R.; Maki, T.; Nakamura, T.; Shirai, T.; Ishizawa, M.; Saeki, T.; Poulter, B.; Ciais, P.

2015-12-01

Atmospheric carbon dioxide (CO2) is the principle driver of anthropogenic climate change. Asia is an important region for the global carbon budget, with four of the world's ten largest national emitters of CO2, but it is also a region with considerable uncertainty in both anthropogenic emissions and land biosphere fluxes of CO2. Furthermore, Asia has undergone rapid economic growth over the past two decades, which has been associated with large increases in fossil fuel emissions, 190% for India and 240% for China between 1990 and 2010. We have used an ensemble of seven atmospheric CO2 inversions and three standard fossil fuel and cement fluxes, based on the inventories of CDIAC, EDGAR and IEA, to determine the land biosphere fluxes for East, South and Southeast Asia, and to ascertain the robustness and overall uncertainty of the results. We find that the East Asian land biosphere was on average a carbon sink of -0.35 ± 0.37 PgC y-1 (median and MAD), or equivalently 17 ± 18% of East Asia's fossil fuel and cement emissions, over 1996 - 2012. Between 1996 - 2001 and 2008 - 2012, we find an increase in the sink of 0.74 ± 0.28 PgC y-1, however the magnitude of this is contingent on the assumed increase in fossil fuel emissions. For South Asia, we find that on average the land biosphere was close to carbon neutral, -0.01 ± 0.20 PgC y-1 over 1996 - 2012 and that there was no significant trend. For Southeast Asia, we find no evidence for a trend in the land biosphere flux over 1996 - 2012 and we cannot determine any difference from carbon neutrality (as assumed a priori by most inversions) with a flux of 0.06 ± 0.29 PgC y-1, throughout this period despite extensive tropical deforestation.

Benthic δ13C stacks: Metrics for deglacial changes in deep ocean carbon storage and the terrestrial biosphere

NASA Astrophysics Data System (ADS)

Peterson, C.; Lisiecki, L. E.

2016-12-01

Across the deglaciation, atmospheric CO2 and global temperatures rise while the deep ocean ventilates carbon to the atmosphere and terrestrial biosphere. As the terrestrial biosphere expands, the mean global ocean δ13C signature increases in response. How well constrained is the global mean benthic δ13C from 20-6 ka? Are the atmosphere and terrestrial biosphere signals in benthic δ13C coupled across the deglaciation? Improved understanding of deglacial carbon cycle interactions can help close the gap between data-based and model-based estimates of global mean benthic δ13C and deep ocean carbon storage changes. Here we present a 118-record compilation of Cibicides wuellerstorfi δ13C time series that span 20-6 kyr. The δ13C records with a resolution better than 3 kyr and gaps between data smaller than 4 kyr are aligned to age models that are constrained by planktic 14C ages (Stern and Lisiecki, 2014). The δ13C records are stacked within nine regions. Then these regional stacks are combined using volume-weighted averages to create intermediate, deep and whole ocean δ13C stacks. The δ13C gradient between the intermediate and deep stacks covaries with atmospheric CO2 change. Meanwhile the deglacial global ocean mean δ13C rise tracks the expansion of the global terrestrial biosphere from 19-6 ka. From this volume-weighted global δ13C stack, the LGM-Holocene mean δ13C change is 0.35±0.10‰ similar to previous estimates (Curry et al., 1988; Duplessy et al., 1988; Peterson et al., 2015; Gebbie et al., 2015). The δ13C stacks and this 4D δ13C compilation are ideal for model-data comparisons and time-stepping 3D visualizations.

Technical Review of the Laboratory Biosphere Closed Ecological System Facility

NASA Astrophysics Data System (ADS)

Dempster, W.; van Thillo, M.; Alling, A.; Allen, J.; Silverstone, S.; Nelson, M.

The "Laboratory Biosphere", a new closed ecological system facility in Santa Fe, New Mexico (USA) has been constructed and became operational in May 2002. Built and operated by the Global Ecotechnics consortium (Biosphere Technologies and Biosphere Foundation with Biospheric Design Inc., and the Institute of Ecotechnics), the research apparatus for intensive crop growth, biogeochemical cycle dynamics and recycling of inedible crop biomass comprises a sealed cylindrical steel chamber and attached variable volume chamber (lung) to prevent pressures caused by the expansion and contraction of the contained air. The cylindrical growing chamber is 3.7m (12 feet) long and 3.7m (12 foot) diameter, giving an internal volume of 34 m3 (1200 ft 3 ). The two crop growth beds cover 5.5 m2, with a soil depth of 0.3m (12 inches), with 12 x 1000 watt high-pressure sodium lights capable of variable lighting of 40-70 mol per m2 per day. A small soil bed reactor in the chamber can be activated to help with metabolism of chamber trace gases. The volume of the attached variable volume chamber (lung) can range between 0-11 m3 (0-400 ft 3 ). Evapotranspired and soil leachate water are collected, combined and recycled to water the planting beds. Sampling ports enable testing of water quality of leachate, condensate and irrigation water. Visual inspection windows provide views of the entire interior and growing beds. The chamber is also outfitted with an airlock to minimize air exchange when people enter and work in the chamber. Continuous sensors include atmospheric CO2 and oxygen, temperature, humidity, soil moisture, light level and water levels in reservoirs. Both "sniffer" (air ports) and "sipper" (water ports) will enable collection of water or air samples for detailed analysis. This paper reports on the development of this new soil-based bioregenerative life support closed system apparatus and its technical challenges and capabilities.

Geological carbon budget of the Mackenzie River Basin: New insight from the oxidation of rock-derived organic carbon

NASA Astrophysics Data System (ADS)

Horan, K.; Hilton, R. G.; Dellinger, M.; Galy, V.; Gaillardet, J.; Tipper, E.; Selby, D. S.; Ottley, C. J.; Burton, K. W.

2016-12-01

Erosion and weathering transfer carbon between the atmosphere and lithospheric storage, thereby operating to modify Earth's long-term climate. Over millions of years, atmospheric carbon dioxide (CO2) is sequestered during the weathering of silicate minerals by carbonic acid, coupled to carbonate formation, and following the erosion of biospheric organic carbon and its burial in sediments. However, erosion and weathering also act together to release CO2 from the lithosphere. Erosion enhances the rate of oxidative weathering of organic carbon in rocks (petrogenic OC, OCpetro), which is a major CO2 source over geological time. In addition, oxidation of sulfide minerals can produce sulfuric acid that weathers carbonate minerals and results in transient CO2 release. Although these sources and sinks of CO2 are well recognised, limited case studies exist where they have been measured alongside each other. Here we calculate the geological carbon budget during weathering and erosion in the Mackenzie River Basin, Canada. The silicate weathering rate, carbonate weathering rate by sulfuric acid and the sedimentary burial of biospheric organic carbon have been constrained by prior work. Closing the long-term CO2 budget therefore requires us to quantify the OCpetro oxidation rate. To do this, we use dissolved rhenium (Re) concentrations as a proxy for OCpetro weathering using samples collected from 2009 to 2013. We normalise dissolved river Re concentrations to the rock Re concentration ([Re]diss/[Re]rock) to assess the variability in oxidative weathering efficiency. We find [Re]diss/[Re]rock ratios are 2-4 times lower than those calculated for rapidly eroding mountain catchments (e.g. Taiwan), which is consistent with a lower physical erosion rate in the Mackenzie Basin. By making assumptions about the concurrent mobility of Re and CO2 during OCpetro weathering we quantify the OCpetro weathering rate and constrain the associated CO2 flux to be 0.3 tC km-2 yr-1. The transient CO2 release by sulfuric acid driven carbonate weathering is 0.8 tC km-2 yr-1. Therefore, these two CO2 sources counter CO2 drawdown by silicate weathering (0.4 tC km-2 yr-1). Nevertheless, OCpetro oxidation does not negate the large CO2 sink driven by biospheric organic carbon erosion (2 tC km-2 yr-1), so the Mackenzie Basin is presently a CO2 sink.

An analytic formula for H-infinity norm sensitivity with applications to control system design

NASA Technical Reports Server (NTRS)

Giesy, Daniel P.; Lim, Kyong B.

1992-01-01

An analytic formula for the sensitivity of singular value peak variation with respect to parameter variation is derived. As a corollary, the derivative of the H-infinity norm of a stable transfer function with respect to a parameter is presented. It depends on some of the first two derivatives of the transfer function with respect to frequency and the parameter. For cases when the transfer function has a linear system realization whose matrices depend on the parameter, analytic formulas for these first two derivatives are derived, and an efficient algorithm for calculating them is discussed. Examples are given which provide numerical verification of the H-infinity norm sensitivity formula and which demonstrate its utility in designing control systems satisfying H-infinity norm constraints. In the appendix, derivative formulas for singular values are paraphrased.

Parameters assessment of the inductively-coupled circuit for wireless power transfer

NASA Astrophysics Data System (ADS)

Isaev, Yu N.; Vasileva, O. V.; Budko, A. A.; Lefebvre, S.

2017-02-01

In this paper, a wireless power transfer model through the example of inductively-coupled coils of irregular shape in software package COMSOL Multiphysics is studied. Circuit parameters, such as inductance, coil resistance and self-capacitance were defined through electromagnetic energy by the finite-element method. The study was carried out according to Helmholtz equation. Spatial distribution of current per unit depending on frequency and the coupling coefficient for analysis of resonant frequency and spatial distribution of the vector magnetic potential at different distances between coils were presented. The resulting algorithm allows simulating the wireless power transfer between the inductively coupled coils of irregular shape with the assessment of the optimal parameters.

Space-dependent perfusion coefficient estimation in a 2D bioheat transfer problem

NASA Astrophysics Data System (ADS)

Bazán, Fermín S. V.; Bedin, Luciano; Borges, Leonardo S.

2017-05-01

In this work, a method for estimating the space-dependent perfusion coefficient parameter in a 2D bioheat transfer model is presented. In the method, the bioheat transfer model is transformed into a time-dependent semidiscrete system of ordinary differential equations involving perfusion coefficient values as parameters, and the estimation problem is solved through a nonlinear least squares technique. In particular, the bioheat problem is solved by the method of lines based on a highly accurate pseudospectral approach, and perfusion coefficient values are estimated by the regularized Gauss-Newton method coupled with a proper regularization parameter. The performance of the method on several test problems is illustrated numerically.

On the parameters influencing air-water gas exchange

NASA Astrophysics Data System (ADS)

JäHne, Bernd; Münnich, Karl Otto; BöSinger, Rainer; Dutzi, Alfred; Huber, Werner; Libner, Peter

1987-02-01

Detailed gas exchange measurements from two circular and one linear wind/wave tunnels are presented. Heat, He, CH4, CO2, Kr, and Xe have been used as tracers. The experiments show the central importance of waves for the water-side transfer process. With the onset of waves the Schmidt number dependence of the transfer velocity k changes from k ∝ Sc-⅔ to k ∝ Sc-½indicating a change in the boundary conditions at the surface. Moreover, energy put into the wave field by wind is transferred to near-surface turbulence enhancing gas transfer. The data show that the mean square slope of the waves is the best parameter to characterize the free wavy surface with respect to water-side transfer processes.

A novel pulsed gas metal arc welding system with direct droplet transfer close-loop control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Q.; Li, P.; Zhang, L.

1994-12-31

In pulsed gas metal arc welding (GMAW), a predominant parameter that has to be monitored and controlled in real time for maintaining process stability and ensuring weld quality, is droplet transfer. Based on the close correlation between droplet transfer and arc light radiant flux in GMAW of steel and aluminum, a direct closed-loop droplet transfer control system for pulsed GMAW with arc light sensor has been developed. By sensing the droplet transfer directly via the arc light signal, a pulsed GMAW process with real and exact one-pulse, one-droplet transfer has been achieved. The novel pulsed GMAW machine consists of threemore » parts: a sensing system, a controlling system, and a welding power system. The software used in this control system is capable of data sampling and processing, parameter matching, optimum parameter restoring, and resetting. A novel arc light sensing system has been developed. The sensor is small enough to be clamped to a semiautomatic welding torch. Based on thissensingn system, a closed-loop droplet transfer control system of GMAW of steel and aluminum has been built and a commercial prototype has been made. The system is capable of keeping one-pulse, one-droplet transfer against external interferences. The welding process with this control system has been proved to be stable, quiet, with no spatter, and provide good weld formation.« less

Hydrodynamics and Heat Transfer in the Case of Combined Flow in a Annular Channel of Small Cross Section

NASA Astrophysics Data System (ADS)

Komov, A. T.; Varava, A. N.; Dedov, A. V.; Zakharenkov, A. V.; Boltenko, É. A.

2017-01-01

The present work is a continuation of experimental investigations conducted at the Moscow Power Engineering Institute (MPEI) on heat-transfer intensification. Brief descriptions of the working section and structure of intensifiers are given and their basic geometric parameters are enumerated. New systematized experimental data on the coefficients of hydraulic resistance and heat transfer in the regime of single-phase convection are given in an extended range of regime parameters and geometric characteristics of the intensifiers. Considerable increase in the heat-transfer coefficient as a function of the geometric characteristics of the intensifier has been established experimentally. The values of the relative fin height, at which these are the maxima of heat transfer and hydraulic resistance, have been established. Calculated dependences for the coefficient of hydraulic resistance and heat transfer have been obtained.

A methodology for the transfer of probabilities between accident severity categories

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whitlow, J. D.; Neuhauser, K. S.

A methodology has been developed which allows the accident probabilities associated with one accident-severity category scheme to be transferred to another severity category scheme. The methodology requires that the schemes use a common set of parameters to define the categories. The transfer of accident probabilities is based on the relationships between probability of occurrence and each of the parameters used to define the categories. Because of the lack of historical data describing accident environments in engineering terms, these relationships may be difficult to obtain directly for some parameters. Numerical models or experienced judgement are often needed to obtain the relationships.more » These relationships, even if they are not exact, allow the accident probability associated with any severity category to be distributed within that category in a manner consistent with accident experience, which in turn will allow the accident probability to be appropriately transferred to a different category scheme.« less

Comparing inversion techniques for constraining CO2 fluxes in the Brazilian Amazon Basin with aircraft observations

NASA Astrophysics Data System (ADS)

Chow, V. Y.; Gerbig, C.; Longo, M.; Koch, F.; Nehrkorn, T.; Eluszkiewicz, J.; Ceballos, J. C.; Longo, K.; Wofsy, S. C.

2012-12-01

The Balanço Atmosférico Regional de Carbono na Amazônia (BARCA) aircraft program spanned the dry to wet and wet to dry transition seasons in November 2008 & May 2009 respectively. It resulted in ~150 vertical profiles covering the Brazilian Amazon Basin (BAB). With the data we attempt to estimate a carbon budget for the BAB, to determine if regional aircraft experiments can provide strong constraints for a budget, and to compare inversion frameworks when optimizing flux estimates. We use a LPDM to integrate satellite-, aircraft-, & surface-data with mesoscale meteorological fields to link bottom-up and top-down models to provide constraints and error bounds for regional fluxes. The Stochastic Time-Inverted Lagrangian Transport (STILT) model driven by meteorological fields from BRAMS, ECMWF, and WRF are coupled to a biosphere model, the Vegetation Photosynthesis Respiration Model (VPRM), to determine regional CO2 fluxes for the BAB. The VPRM is a prognostic biosphere model driven by MODIS 8-day EVI and LSWI indices along with shortwave radiation and temperature from tower measurements and mesoscale meteorological data. VPRM parameters are tuned using eddy flux tower data from the Large-Scale Biosphere Atmosphere experiment. VPRM computes hourly CO2 fluxes by calculating Gross Ecosystem Exchange (GEE) and Respiration (R) for 8 different vegetation types. The VPRM fluxes are scaled up to the BAB by using time-averaged drivers (shortwave radiation & temperature) from high-temporal resolution runs of BRAMS, ECMWF, and WRF and vegetation maps from SYNMAP and IGBP2007. Shortwave radiation from each mesoscale model is validated using surface data and output from GL 1.2, a global radiation model based on GOES 8 visible imagery. The vegetation maps are updated to 2008 and 2009 using landuse scenarios modeled by Sim Amazonia 2 and Sim Brazil. A priori fluxes modeled by STILT-VPRM are optimized using data from BARCA, eddy covariance sites, and flask measurements. The aircraft mixing ratios are applied as a top down constraint in Maximum Likelihood Estimation (MLE) and Bayesian inversion frameworks that solves for parameters controlling the flux. Posterior parameter estimates are used to estimate the carbon budget of the BAB. Preliminary results show that the STILT-VPRM model simulates the net emission of CO2 during both transition periods reasonably well. There is significant enhancement from biomass burning during the November 2008 profiles and some from fossil fuel combustion during the May 2009 flights. ΔCO/ΔCO2 emission ratios are used in combination with continuous observations of CO to remove the CO2 contributions from biomass burning and fossil fuel combustion from the observed CO2 measurements resulting in better agreement of observed and modeled aircraft data. Comparing column calculations for each of the vertical profiles shows our model represents the variability in the diurnal cycle. The high altitude CO2 values from above 3500m are similar to the lateral boundary conditions from CarbonTracker 2010 and GEOS-Chem indicating little influence from surface fluxes at these levels. The MLE inversion provides scaling factors for GEE and R for each of the 8 vegetation types and a Bayesian inversion is being conducted. Our initial inversion results suggest the BAB represents a small net source of CO2 during both of the BARCA intensives.

Hydromagnetic flow of a Cu-water nanofluid past a moving wedge with viscous dissipation

NASA Astrophysics Data System (ADS)

M. Salem, A.; Galal, Ismail; Rania, Fathy

2014-04-01

A numerical study is performed to investigate the flow and heat transfer at the surface of a permeable wedge immersed in a copper (Cu)-water-based nanofluid in the presence of magnetic field and viscous dissipation using a nanofluid model proposed by Tiwari and Das (Tiwari I K and Das M K 2007 Int. J. Heat Mass Transfer 50 2002). A similarity solution for the transformed governing equation is obtained, and those equations are solved by employing a numerical shooting technique with a fourth-order Runge-Kutta integration scheme. A comparison with previously published work is carried out and shows that they are in good agreement with each other. The effects of velocity ratio parameter λ, solid volume fraction φ, magnetic field M, viscous dissipation Ec, and suction parameter Fw on the fluid flow and heat transfer characteristics are discussed. The unique and dual solutions for self-similar equations of the flow and heat transfer are analyzed numerically. Moreover, the range of the velocity ratio parameter for which the solution exists increases in the presence of magnetic field and suction parameter.

Mixed convection and heat generation/absorption aspects in MHD flow of tangent-hyperbolic nanoliquid with Newtonian heat/mass transfer

NASA Astrophysics Data System (ADS)

Qayyum, Sajid; Hayat, Tasawar; Shehzad, Sabir Ali; Alsaedi, Ahmed

2018-03-01

This article concentrates on the magnetohydrodynamic (MHD) stagnation point flow of tangent hyperbolic nanofluid in the presence of buoyancy forces. Flow analysis caused due to stretching surface. Characteristics of heat transfer are examined under the influence of thermal radiation and heat generation/absorption. Newtonian conditions for heat and mass transfer are employed. Nanofluid model includes Brownian motion and thermophoresis. The governing nonlinear partial differential systems of the problem are transformed into a systems of nonlinear ordinary differential equations through appropriate variables. Impact of embedded parameters on the velocity, temperature and nanoparticle concentration fields are presented graphically. Numerical computations are made to obtain the values of skin friction coefficient, local Nusselt and Sherwood numbers. It is concluded that velocity field enhances in the frame of mixed convection parameter while reverse situation is observed due to power law index. Effect of Brownian motion parameter on the temperature and heat transfer rate is quite reverse. Moreover impact of solutal conjugate parameter on the concentration and local Sherwood number is quite similar.

Heat transfer characteristics within an array of impinging jets. Effects of crossflow temperature relative to jet temperature

NASA Technical Reports Server (NTRS)

Florschuetz, L. W.; Su, C. C.

1985-01-01

Spanwise average heat fluxes, resolved in the streamwise direction to one stream-wise hole spacing were measured for two-dimensional arrays of circular air jets impinging on a heat transfer surface parallel to the jet orifice plate. The jet flow, after impingement, was constrained to exit in a single direction along the channel formed by the jet orifice plate and heat transfer surface. The crossflow originated from the jets following impingement and an initial crossflow was present that approached the array through an upstream extension of the channel. The regional average heat fluxes are considered as a function of parameters associated with corresponding individual spanwise rows within the array. A linear superposition model was employed to formulate appropriate governing parameters for the individual row domain. The effects of flow history upstream of an individual row domain are also considered. The results are formulated in terms of individual spanwise row parameters. A corresponding set of streamwise resolved heat transfer characteristics formulated in terms of flow and geometric parameters characterizing the overall arrays is described.

Heat transfer in porous medium embedded with vertical plate: Non-equilibrium approach - Part B

DOE Office of Scientific and Technical Information (OSTI.GOV)

Quadir, G. A., E-mail: Irfan-magami@Rediffmail.com, E-mail: gaquadir@gmail.com; Badruddin, Irfan Anjum

2016-06-08

This work is continuation of the paper Part A. Due to large number of results, the paper is divided into two section with section-A (Part A) discussing the effect of various parameters such as heat transfer coefficient parameter, thermal conductivity ratio etc. on streamlines and isothermal lines. Section-B highlights the heat transfer characteristics in terms of Nusselt number The Darcy model is employed to simulate the flow inside the medium. It is assumed that the heat transfer takes place by convection and radiation. The governing partial differential equations are converted into non-dimensional form and solved numerically using finite element method.

Determining the Carbon Transport Rate of an Enclosed Tropical Rainforest Ecosystem in Biosphere 2

NASA Astrophysics Data System (ADS)

Takagi, Y. A.; Van Haren, J. L.

2013-12-01

Determining how carbon moves through a tropical rainforest ecosystem is an important step towards understanding its role as a carbon sink system in the global carbon cycle. The paths by which carbon moves through forest ecosystems are reasonably well known. However, very little is known about how quickly this happens. We will present data from experiments where we isotopically pulse label the atmospheric carbon dioxide within the Biosphere 2 tropical rainforest biome with natural gas derived CO2 (∂13C ~ -40‰ vs. ~ -8.5‰ for ambient air). We are continually monitoring the CO2 concentration and isotope composition of the ambient air along a vertical profile to measure ecosystem gas exchange, and that of six branch-bag and five soil-chamber locations within the Biosphere 2 tropical rainforest, with an Aerodyne Quantum Cascade Laser to trace the labeled carbon (precision for ∂13C = 0.02‰ and CO2 = 0.07ppm, calibrated to NOAA air standards). Environmental parameters such as light, relative humidity, soil moisture, and temperature are monitored at fifteen-minute intervals. We have selected one vine species and three different tree species for branch bag enclosures at two canopy heights that we expect represent the bulk photosynthetic biomass of the rainforest. The soil chambers are distributed randomly. By treating the Biosphere 2 tropical rainforest biome, a glass enclosed ecosystem with 1900m2 of ground, 26700m3 of air, and 92 different plant species, as a model ecosystem, we anticipate to determine carbon transport rates that would otherwise be practically impossible to determine in the real world due to the difficulty of isotopically labeling and monitoring entire canopies or even individual trees, which can reach heights over 60m. The data we have collected thus far will provide a baseline comparison for the labeling data. Comparing the branch bag data with the ecosystem data has helped us determine how well small branches represent the canopy and whole ecosystem behavior. We have also determined the natural abundance ∂13C isotope fractionation rates of photosynthesis (ranging from -14‰ to -20‰, depending on the species, location within the canopy, and environmental conditions) and respiration (ranging from -25‰ to -29‰). From the lag time in the isotope signal at each location, we will derive the carbon transport rate: the time it takes for carbon to travel from the atmosphere through the carbon cycle pathways to these locations. We intend to present data from several labeling runs, which will last a week to several weeks each, depending on the lag times, especially in the soil chambers. At the conclusion of these runs, we expect to be able to propose the first experimentally derived model for tropical rainforest carbon transport rates.

Influence of speckle image reconstruction on photometric precision for large solar telescopes

NASA Astrophysics Data System (ADS)

Peck, C. L.; Wöger, F.; Marino, J.

2017-11-01

Context. High-resolution observations from large solar telescopes require adaptive optics (AO) systems to overcome image degradation caused by Earth's turbulent atmosphere. AO corrections are, however, only partial. Achieving near-diffraction limited resolution over a large field of view typically requires post-facto image reconstruction techniques to reconstruct the source image. Aims: This study aims to examine the expected photometric precision of amplitude reconstructed solar images calibrated using models for the on-axis speckle transfer functions and input parameters derived from AO control data. We perform a sensitivity analysis of the photometric precision under variations in the model input parameters for high-resolution solar images consistent with four-meter class solar telescopes. Methods: Using simulations of both atmospheric turbulence and partial compensation by an AO system, we computed the speckle transfer function under variations in the input parameters. We then convolved high-resolution numerical simulations of the solar photosphere with the simulated atmospheric transfer function, and subsequently deconvolved them with the model speckle transfer function to obtain a reconstructed image. To compute the resulting photometric precision, we compared the intensity of the original image with the reconstructed image. Results: The analysis demonstrates that high photometric precision can be obtained for speckle amplitude reconstruction using speckle transfer function models combined with AO-derived input parameters. Additionally, it shows that the reconstruction is most sensitive to the input parameter that characterizes the atmospheric distortion, and sub-2% photometric precision is readily obtained when it is well estimated.

On the Relationship Between Transfer Function-derived Response Times and Hydrograph Analysis Timing Parameters: Are there Similarities?

NASA Astrophysics Data System (ADS)

Bansah, S.; Ali, G.; Haque, M. A.; Tang, V.

2017-12-01

The proportion of precipitation that becomes streamflow is a function of internal catchment characteristics - which include geology, landscape characteristics and vegetation - and influence overall storage dynamics. The timing and quantity of water discharged by a catchment are indeed embedded in event hydrographs. Event hydrograph timing parameters, such as the response lag and time of concentration, are important descriptors of how long it takes the catchment to respond to input precipitation and how long it takes the latter to filter through the catchment. However, the extent to which hydrograph timing parameters relate to average response times derived from fitting transfer functions to annual hydrographs is unknown. In this study, we used a gamma transfer function to determine catchment average response times as well as event-specific hydrograph parameters across a network of eight nested watersheds ranging from 0.19 km2 to 74.6 km2 prairie catchments located in south central Manitoba (Canada). Various statistical analyses were then performed to correlate average response times - estimated using the parameters of the fitted gamma transfer function - to event-specific hydrograph parameters. Preliminary results show significant interannual variations in response times and hydrograph timing parameters: the former were in the order of a few hours to days, while the latter ranged from a few days to weeks. Some statistically significant relationships were detected between response times and event-specific hydrograph parameters. Future analyses will involve the comparison of statistical distributions of event-specific hydrograph parameters with that of runoff response times and baseflow transit times in order to quantity catchment storage dynamics across a range of temporal scales.

Mars Analog Rio Tinto Experiment (MARTE): 2003 Drilling Campaign to Search for a Subsurface Biosphere at Rio Tinto Spain

NASA Technical Reports Server (NTRS)

Stoker, Carol; Dunagan, Stephen; Stevens, Todd; Amils, Ricardo; Gomez-Elvira, Javier; Fernandez, David; Hall, James; Lynch, Kennda; Cannon, Howard; Zavaleta, Jhony

2004-01-01

The MARTE (Mars Astrobiology Research and Technology Experiment) project, an ASTEP field experiment, is exploring for a hypothesized subsurface anaerobic chemoautotrophic biosphere in the region of the Tinto River- or Rio Tinto- in southwestern Spain. It is also demonstrating technology needed to search for a subsurface biosphere on Mars. The project has three primary objectives: (1) search for and characterize subsurface life at Rio Tinto along with the physical and chemical properties and sustaining energy sources of its environment, (2) perform a high fidelity simulation of a robotic Mars drilling mission to search for life, and (3) demonstrate the drilling, sample handling, and instrument technologies relevant to searching for life on Mars. The simulation of the robotic drilling mission is guided by the results of the aseptic drilling campaign to search for life at Rio Tinto. This paper describes results of the first phase of the aseptic drilling campaign.

Cosmic Rays as a Factor of Biosphere Evolution

NASA Astrophysics Data System (ADS)

Miroshnichenko, L. I.

2014-11-01

There are no doubts that the Earth's space environment in the past inevitably exerted direct and/or indirect influence [1--4] on the conditions of terrestrial life and biospheric evolution. Well-known cosmic factors are usually streams of cosmic dust and gas, comets and asteroids, cosmic rays (energetic particles of galactic and/or solar origin), interplanetary plasma (solar wind), and electromagnetic radiation of different energies, wavelengths, or frequencies. Of great interest are radiation conditions and their variations, especially in the remote past (over the geological time scales). The Sun, the most important and indispensable condition for the existence of the Earth's biosphere, is also a potential source of dangerous emissions. In continuation of (and in addition to) our review paper [3], below we summarize the observational data and results of theoretical works that have been carried out and/or published mainly after 2012. These studies are actually in the frontier region between the Astrobiology and Space Weather. Our main attention is paid to cosmic rays (CR) of galactic and solar origin (GCR and SCR, respectively).

Agricultural ecosystems - The world is watching

DOE Office of Scientific and Technical Information (OSTI.GOV)

Madison, M.F.; Licht, L.A.

1990-02-01

Environmental degradation is displacing nuclear war as the overriding concern of the world's people. An accusing finger is rightfully pointed at agricultural practices - for degrading water, air, food, and societal quality. As reported in the popular and technical press, there is a clamor for farming technology that is both productive and ecological. We cannot survive without a productive agriculture. Yet, the eroding soil, the degrading water quality, the decrease in farm profitability, the reductions in wildlife populations, and the closing store fronts in rural America point to a need for new management approaches. The word sustainable continues to bemore » mentioned as an underlying theme for future management techniques. Soil, air, and water form a seamless whole - the thin envelope we call the biosphere. The term sustainable agriculture implies a nourishing stewardship of the biosphere when used by farmers in pursuit of their livelihood. This biosphere simultaneously produces and sustains a multitude of products, including ourselves. It is all we have to create both our present and our future.« less

'Rare biosphere' bacteria as key phenanthrene degraders in coastal seawaters.

PubMed

Sauret, Caroline; Séverin, Tatiana; Vétion, Gilles; Guigue, Catherine; Goutx, Madeleine; Pujo-Pay, Mireille; Conan, Pascal; Fagervold, Sonja K; Ghiglione, Jean-François

2014-11-01

By coupling DNA-SIP and pyrosequencing approaches, we identified Cycloclasticus sp. as a keystone degrader of polycyclic aromatic hydrocarbons (PAH) despite being a member of the 'rare biosphere' in NW Mediterranean seawaters. We discovered novel PAH-degrading bacteria (Oceanibaculum sp., Sneathiella sp.) and we identified other groups already known to possess this function (Alteromonas sp., Paracoccus sp.). Together with Cycloclasticus sp., these groups contributed to potential in situ phenanthrene degradation at a rate >0.5 mg l(-1) day(-1), sufficient to account for a considerable part of PAH degradation. Further, we characterized the PAH-tolerant bacterial communities, which were much more diverse in the polluted site by comparison to unpolluted marine references. PAH-tolerant bacteria were also members of the rare biosphere, such as Glaciecola sp. Collectively, these data show the complex interactions between PAH-degraders and PAH-tolerant bacteria and provide new insights for the understanding of the functional ecology of marine bacteria in polluted waters. Copyright © 2014 Elsevier Ltd. All rights reserved.

Exploration and protection of Europa's biosphere: implications of permeable ice.

PubMed

Greenberg, Richard

2011-03-01

Europa has become a high-priority objective for exploration because it may harbor life. Strategic planning for its exploration has been predicated on an extreme model in which the expected oceanic biosphere lies under a thick ice crust, buried too deep to be reached in the foreseeable future, which would beg the question of whether other active satellites might be more realistic objectives. However, Europa's ice may in fact be permeable, with very different implications for the possibilities for life and for mission planning. A biosphere may extend up to near the surface, making life far more readily accessible to exploration while at the same time making it vulnerable to contamination. The chances of finding life on Europa are substantially improved while the need for planetary protection becomes essential. The new National Research Council planetary protection study will need to go beyond its current mandate if meaningful standards are to be put in place. © Mary Ann Liebert, Inc.

Modelling of intermittent microwave convective drying: parameter sensitivity

NASA Astrophysics Data System (ADS)

Zhang, Zhijun; Qin, Wenchao; Shi, Bin; Gao, Jingxin; Zhang, Shiwei

2017-06-01

The reliability of the predictions of a mathematical model is a prerequisite to its utilization. A multiphase porous media model of intermittent microwave convective drying is developed based on the literature. The model considers the liquid water, gas and solid matrix inside of food. The model is simulated by COMSOL software. Its sensitivity parameter is analysed by changing the parameter values by ±20%, with the exception of several parameters. The sensitivity analysis of the process of the microwave power level shows that each parameter: ambient temperature, effective gas diffusivity, and evaporation rate constant, has significant effects on the process. However, the surface mass, heat transfer coefficient, relative and intrinsic permeability of the gas, and capillary diffusivity of water do not have a considerable effect. The evaporation rate constant has minimal parameter sensitivity with a ±20% value change, until it is changed 10-fold. In all results, the temperature and vapour pressure curves show the same trends as the moisture content curve. However, the water saturation at the medium surface and in the centre show different results. Vapour transfer is the major mass transfer phenomenon that affects the drying process.

Concerning evaluation of eco-geochemical background in remediation strategy

NASA Astrophysics Data System (ADS)

Korobova, Elena; Romanov, Sergey

2015-04-01

The geochemical concept of biosphere developed by V.I. Vernadsky states the geological role of the living organisms in the course of their active chemical interaction with the inert matter (Vernadsky, 1926, 1960). Basing on this theory it is reasonable to suggest that coevolution of living organisms and their environment led to development of the dynamically stable biogeocenoses precisely adequate to their geochemical environment. Soil cover was treated by V.I. Vernadsky as a balanced bio-inert matter resulting from this interaction. Appearance of human mind and then a civilization led to global expansion of human beings, first able to survive in unfavorable geochemical conditions and then starting chemical transformation of the environment to satisfy the growing demands of mankind in food and energy. The residence in unfavorable environment and local contamination was followed by appearance of endemic diseases of plants, animals and man. Therefore zonal, regional and local chemical composition of the soil cover formed in natural conditions may be used for estimation of the optimum geochemical background, most adequate for the corresponding zonal biogeocenoses and species. Moreover, the natural geochemical background and technogenic fields have unequal spatial structure and this facilitates their identification that may be relatively easy realized in remediation strategy. On the assumption of the foregoing, the adequate methodical approach to remediation of technogenically affected areas should account of the interaction of the existing natural and the newly formed technogenic geochemical fields and include the following steps: 1) the study and mapping of geochemical structure of the natural geochemical background basing on soil maps; 2) the study of contaminants and mapping spatial distribution of technogenic releases; 3) construction of risk maps for the target risk groups with due regard to natural ecological threshold concentration in context of risk degree for plants and animals (Kovalsky, 1974; Letunova, Kovalsky, 1978, Ermakov, 1999). Obtained zones of different eco-geochemical risk need particular strategy basing on maximum possible correspondence to the natural geochemical conditions. For example, the assessment of effects of the nuclear accident in any case needs taking into account the synergetic results of ionizing radiation in different eco-geochemical conditions. In this respect the most contaminated areas should be withdrawn from living but some spatial arable lands can be used for seeds or technical crops production. The less contaminated areas still used in agriculture need shifting to fodder or species giving non-contaminated products (e.g. oil). Wet meadows of superaqueous landscapes with a relatively high radionuclide transfer to the plants should be excluded from grazing but other areas with lower transfer to forage may be used. In all the cases the resultant remediation should achieve first of all the maximum decrease of the summary negative health effect for the residents or working personnel. References Vernadsky V.I., 1926. Biosphere. Leningrad, Nauch. khim.-tekhn. izd-vo, 147 p. Vernadsky V.I., 1960. Selected works, Vol. 5. Moscow, izd-vo AN SSSR, 422 p. Kovalsky V.V., 1974. Geochemical ecology. Moscow, Nauka, Letunova S.V., Kovalsky V.V., 1978. Geochemical ecology of microorganisms. Moscow, Nauka, 148 pp. Ermakov V.V., 1999.Geochemical ecology as a result of the system-based study of the biosphere. Problems of biogeochemistry and geochemical ecology. Transactions of the Biogeochem. Lab., 23, Moscow, Nauka, 152-182.

Constrained parameterisation of photosynthetic capacity causes significant increase of modelled tropical vegetation surface temperature

NASA Astrophysics Data System (ADS)

Kattge, J.; Knorr, W.; Raddatz, T.; Wirth, C.

2009-04-01

Photosynthetic capacity is one of the most sensitive parameters of terrestrial biosphere models whose representation in global scale simulations has been severely hampered by a lack of systematic analyses using a sufficiently broad database. Due to its coupling to stomatal conductance changes in the parameterisation of photosynthetic capacity may potentially influence transpiration rates and vegetation surface temperature. Here, we provide a constrained parameterisation of photosynthetic capacity for different plant functional types in the context of the photosynthesis model proposed by Farquhar et al. (1980), based on a comprehensive compilation of leaf photosynthesis rates and leaf nitrogen content. Mean values of photosynthetic capacity were implemented into the coupled climate-vegetation model ECHAM5/JSBACH and modelled gross primary production (GPP) is compared to a compilation of independent observations on stand scale. Compared to the current standard parameterisation the root-mean-squared difference between modelled and observed GPP is substantially reduced for almost all PFTs by the new parameterisation of photosynthetic capacity. We find a systematic depression of NUE (photosynthetic capacity divided by leaf nitrogen content) on certain tropical soils that are known to be deficient in phosphorus. Photosynthetic capacity of tropical trees derived by this study is substantially lower than standard estimates currently used in terrestrial biosphere models. This causes a decrease of modelled GPP while it significantly increases modelled tropical vegetation surface temperatures, up to 0.8°C. These results emphasise the importance of a constrained parameterisation of photosynthetic capacity not only for the carbon cycle, but also for the climate system.

Effect of Cattaneo-Christov heat flux on buoyancy MHD nanofluid flow and heat transfer over a stretching sheet in the presence of Joule heating and thermal radiation impacts

NASA Astrophysics Data System (ADS)

Dogonchi, A. S.; Ganji, D. D.

2018-06-01

In this study, buoyancy MHD nanofluid flow and heat transfer over a stretching sheet in the presence of Joule heating and thermal radiation impacts, are studied. Cattaneo-Christov heat flux model instead of conventional Fourier's law of heat conduction is applied to investigate the heat transfer characteristics. A similarity transformation is used to transmute the governing momentum and energy equations into non-linear ordinary differential equations with the appropriate boundary conditions. The obtained non-linear ordinary differential equations are solved numerically. The impacts of diverse active parameters such as the magnetic parameter, the radiation parameter, the buoyancy parameter, the heat source parameter, the volume fraction of nanofluid and the thermal relaxation parameter are examined on the velocity and temperature profiles. In addition, the value of the Nusselt number is calculated and presented through figures. The results demonstrate that the temperature profile is lower in the case of Cattaneo-Christov heat flux model as compared to Fourier's law. Moreover, the Nusselt number raises with the raising volume fraction of nanofluid and it abates with the ascending the radiation parameter.

An Investigation of the Critical Events and Influential Factors to the Evolution of the U.S. Man and the Biosphere Program

NASA Astrophysics Data System (ADS)

Thomsen, Jennifer M.

2018-04-01

The UNESCO Man and the Biosphere program has operated for 45 years as an international program that started in the 1970s to conserve biotic communities and provide areas for research, education, and training. The program later evolved in the 1990s to address social and environmental issues in a sustainable manner across a landscape. This program was one of the first efforts that recognized the importance of working beyond park and protected area boundaries and the need to sustain livelihoods as much as the resources. In the MAB program's infancy, the United States (U.S.) was a major advocate and leader with more than 45 biosphere reserves, most of them established in or around 1976. Yet, many political, economic, and other external factors influenced the U.S. MAB involvement in subsequent years. Consequently, the U.S. has remained largely inactive in the international MAB network for the past fifteen years until a recent push to revive the program under the leadership of the State Department and the National Park Service. Through in-depth research on two longterm U.S. biosphere reserves, this paper provides a description of the key events impacting the U.S. MAB program over the past several decades and discusses the influential role of politics, a public image, and the perceptions of international designations. Through the lessons presented in this paper, recommendations are provided to support the revival of the MAB program in the U.S.

The deep, hot biosphere: Twenty-five years of retrospection.

PubMed

Colman, Daniel R; Poudel, Saroj; Stamps, Blake W; Boyd, Eric S; Spear, John R

2017-07-03

Twenty-five years ago this month, Thomas Gold published a seminal manuscript suggesting the presence of a "deep, hot biosphere" in the Earth's crust. Since this publication, a considerable amount of attention has been given to the study of deep biospheres, their role in geochemical cycles, and their potential to inform on the origin of life and its potential outside of Earth. Overwhelming evidence now supports the presence of a deep biosphere ubiquitously distributed on Earth in both terrestrial and marine settings. Furthermore, it has become apparent that much of this life is dependent on lithogenically sourced high-energy compounds to sustain productivity. A vast diversity of uncultivated microorganisms has been detected in subsurface environments, and we show that H 2 , CH 4 , and CO feature prominently in many of their predicted metabolisms. Despite 25 years of intense study, key questions remain on life in the deep subsurface, including whether it is endemic and the extent of its involvement in the anaerobic formation and degradation of hydrocarbons. Emergent data from cultivation and next-generation sequencing approaches continue to provide promising new hints to answer these questions. As Gold suggested, and as has become increasingly evident, to better understand the subsurface is critical to further understanding the Earth, life, the evolution of life, and the potential for life elsewhere. To this end, we suggest the need to develop a robust network of interdisciplinary scientists and accessible field sites for long-term monitoring of the Earth's subsurface in the form of a deep subsurface microbiome initiative.

Biospheric Cooling and the Emergence of Intelligence

NASA Astrophysics Data System (ADS)

Schwartzman, David; Middendorf, George

The long-term cooling history of the Earth's biosphere implies a temperature constraint on the timing of major events in biologic evolution, e.g., emergence of cyanobacteria, eucaryotes and Metazoa apparently occurred at times when temperatures were near their upper growth limits. Could biospheric cooling also have been a necessary condition for the emergence of veterbrates and their encephalization? The upper temperature limit for vertebrate growth is about 10 degrees below the limit for Metazoa (50 degrees C). Heterothermy followed by full homeothermy was likely a necessary condition for greater encephalization because of the energy requirement of larger brains. The temperature differential between an animal and a cooler environment, all other factors equal, will increase the efficiency of heat loss from the brain, but too large a differential will shift metabolic energy away from the brain to the procurement of food. Encephalization has also entailed the evolution of internal cooling mechanisms to avoid overheating the brain. The two periods of pronounced Phanerozoic cooling, the PermoCarboniferous and late Cenozoic, corresponded to the emergence of mammal-like reptiles and hominids respectively, with a variety of explanations offered for the apparent link. The origin of highly encephalized whales, dolphins and porpoises occurred with the drop in ocean temperatures 25-30 mya. Of course, other possible paths to encephalization are conceivable, with radically different solutions to the problem of heat dissipation. But the intrinsic requirements for information processing capacity necessary for intelligence suggest our terrestrial pattern may resemble those of alien biospheres given similar histories.

Value orientation and payment for ecosystem services: Perceived detrimental consequences lead to willingness-to-pay for ecosystem services.

PubMed

Obeng, Elizabeth Asantewaa; Aguilar, Francisco Xavier

2018-01-15

This research analyzed whether the three distinct value orientations posited under the Value-Belief-Norm (VBN) model determine willingness-to-pay (WTP) for a payment for ecosystem services (PES) program. A survey instrument gathered U.S. residents' knowledge and attitudes toward ecosystem services and PES, and elicited WTP for the restoration of a hypothetical degraded forest watershed for improved ecosystem services. Data from over 1000 respondents nationwide were analyzed using exploratory factor analysis (EFA) and ordered logistic regression. Urban respondents were more familiar with the concepts of ecosystem service and PES than rural respondents but familiarity did not yield statistically different WTP estimates. Based on results from the EFA, we posit that latent value orientations might be distinguished as 'detrimental', 'biospheric' and 'beneficial (egoistic)' - as compared to 'altruistic', 'biospheric' and 'egoistic' as suggested in the VBN's general awareness of consequences scale. Awareness of biospheric and detrimental consequences along with ascriptions to personal norms had positive and significant effects on stated WTP. Beneficial (egoistic) value orientation was negatively associated with WTP and carried a negative average WTP per household per year (US$ -30.48) for the proposed PES restoration program as compared with biospheric (US$ 15.53) and detrimental (US$ 3.96) orientations. Besides personal norms, awareness of detrimental consequences to human wellbeing from environmental degradation seems the stronger driver of WTP for the restoration and protection of forest watershed ecosystem services under a PES program. Copyright © 2017 Elsevier Ltd. All rights reserved.

An Investigation of the Critical Events and Influential Factors to the Evolution of the U.S. Man and the Biosphere Program.

PubMed

Thomsen, Jennifer M

2018-04-01

The UNESCO Man and the Biosphere program has operated for 45 years as an international program that started in the 1970s to conserve biotic communities and provide areas for research, education, and training. The program later evolved in the 1990s to address social and environmental issues in a sustainable manner across a landscape. This program was one of the first efforts that recognized the importance of working beyond park and protected area boundaries and the need to sustain livelihoods as much as the resources. In the MAB program's infancy, the United States (U.S.) was a major advocate and leader with more than 45 biosphere reserves, most of them established in or around 1976. Yet, many political, economic, and other external factors influenced the U.S. MAB involvement in subsequent years. Consequently, the U.S. has remained largely inactive in the international MAB network for the past fifteen years until a recent push to revive the program under the leadership of the State Department and the National Park Service. Through in-depth research on two longterm U.S. biosphere reserves, this paper provides a description of the key events impacting the U.S. MAB program over the past several decades and discusses the influential role of politics, a public image, and the perceptions of international designations. Through the lessons presented in this paper, recommendations are provided to support the revival of the MAB program in the U.S.

Snowball Earth: Response of the biosphere?

NASA Astrophysics Data System (ADS)

Runnegar, B.

2001-05-01

Snowball Earth is a script for global catastrophe that rivals giant impact theories in the likely severity of its environmental effects. This is particularly true for the "hard" version of the hypothesis, which requires the atmosphere to be effectively isolated from the ocean so that its carbon dioxide concentration can build up to the level ( ~100 PAL) ultimately required to melt the ice. However, coupled GCM-EMB models (Hyde et al. Nature 405, 425-430; Crowley & Hyde, GRL 28, 283-286) allow equatorial open water solutions under plausible Neoproterozoic conditions. These "softer" scenarios are more appealing if one considers the possible effects of snowball Earth episodes on the global biosphere. The meager Neoproterozoic fossil record makes it difficult to observe the biospheric response directly, but we know from evolutionary trees constructed from aligned protein and DNA sequences from living organisms, calibrated by the fossil record, that many lines of descent passed through the Cryogenian glacial periods. They include various kinds of prokaryotic and eukaryotic algae, a range of protists, and probably, a number of different kinds of animals and fungi. In addition, most of the microbial groups shown on comprehensive 16S rRNA trees have molecular clock ages that predate the snowball episodes. As the global environmental perturbations associated with the "hard" snowball hypothesis (freezing temperatures; huge and rapid changes in temperature; sudden carbon dioxide overload) are thought to have been biologically limiting during the Phanerozoic, the inferred response of the biosphere to Neoprotereozic glaciations may, indeed, provide a way of testing alternative snowball Earth scenarios.

Modelling Sensor and Target effects on LiDAR Waveforms

NASA Astrophysics Data System (ADS)

Rosette, J.; North, P. R.; Rubio, J.; Cook, B. D.; Suárez, J.

2010-12-01

The aim of this research is to explore the influence of sensor characteristics and interactions with vegetation and terrain properties on the estimation of vegetation parameters from LiDAR waveforms. This is carried out using waveform simulations produced by the FLIGHT radiative transfer model which is based on Monte Carlo simulation of photon transport (North, 1996; North et al., 2010). The opportunities for vegetation analysis that are offered by LiDAR modelling are also demonstrated by other authors e.g. Sun and Ranson, 2000; Ni-Meister et al., 2001. Simulations from the FLIGHT model were driven using reflectance and transmittance properties collected from the Howland Research Forest, Maine, USA in 2003 together with a tree list for a 200m x 150m area. This was generated using field measurements of location, species and diameter at breast height. Tree height and crown dimensions of individual trees were calculated using relationships established with a competition index determined for this site. Waveforms obtained by the Laser Vegetation Imaging Sensor (LVIS) were used as validation of simulations. This provided a base from which factors such as slope, laser incidence angle and pulse width could be varied. This has enabled the effect of instrument design and laser interactions with different surface characteristics to be tested. As such, waveform simulation is relevant for the development of future satellite LiDAR sensors, such as NASA’s forthcoming DESDynI mission (NASA, 2010), which aim to improve capabilities of vegetation parameter estimation. ACKNOWLEDGMENTS We would like to thank scientists at the Biospheric Sciences Branch of NASA Goddard Space Flight Center, in particular to Jon Ranson and Bryan Blair. This work forms part of research funded by the NASA DESDynI project and the UK Natural Environment Research Council (NE/F021437/1). REFERENCES NASA, 2010, DESDynI: Deformation, Ecosystem Structure and Dynamics of Ice. http://desdyni.jpl.nasa.gov/ (accessed May 2010). NI-MEISTER, W., JUPP, D. L. B. and DUBAYAH, R., 2001, Modeling Lidar Waveforms in Heterogeneous and Discrete Canopies. IEEE Transactions on Geoscience and Remote Sensing, 39 (9): 1943-1958. NORTH, P. R. J., 1996, Three-Dimensional Forest Light Interaction Model Using a Monte Carlo Method. IEEE Transactions on Geoscience and Remote Sensing, 34 (4): 946-956. NORTH, P. R. J., ROSETTE, J. A. B., SUÁREZ, J. C. and LOS, S. O., 2010, A Monte Carlo radiative transfer model of satellite waveform lidar. International Journal of Remote Sensing, 31 (5): 1343-1358. SUN, G. and RANSON, K. J., 2000, Modeling lidar returns from forest canopies. IEEE Transactions on Geoscience and Remote Sensing, 38 (6): 2617-2626.

Worldwide Historical Estimates of Leaf Area Index, 1932-2000

NASA Technical Reports Server (NTRS)

Scurlock, J. M. O.; Asner, G. P.; Gower, S. T.

2001-01-01

Approximately 1000 published estimates of leaf area index (LAI) from nearly 400 unique field sites, covering the period 1932-2000, have been compiled into a single data set. LA1 is a key parameter for global and regional models of biosphere/atmosphere exchange of carbon dioxide, water vapor, and other materials. It also plays an integral role in determining the energy balance of the land surface. This data set provides a benchmark of typical values and ranges of LA1 for a variety of biomes and land cover types, in support of model development and validation of satellite-derived remote sensing estimates of LA1 and other vegetation parameters. The LA1 data are linked to a bibliography of over 300 originalsource references.This report documents the development of this data set, its contents, and its availability on the Internet from the Oak Ridge National Laboratory Distributed Active Archive Center for Biogeochemical Dynamics. Caution is advised in using these data, which were collected using a wide range of methodologies and assumptions that may not allow comparisons among sites.

Remote sensing of wetland parameters related to carbon cycling

NASA Technical Reports Server (NTRS)

Bartlett, David S.; Johnson, Robert W.

1985-01-01

Measurement of the rates of important biogeochemical fluxes on regional or global scales is vital to understanding the geochemical and climatic consequences of natural biospheric processes and of human intervention in those processes. Remote data gathering and interpretation techniques were used to examine important cycling processes taking place in wetlands over large geographic expanses. Large area estimation of vegetative biomass and productivity depends upon accurate, consistent measurements of canopy spectral reflectance and upon wide applicability of algorithms relating reflectance to biometric parameters. Results of the use of airborne multispectral scanner data to map above-ground biomass in a Delaware salt marsh are shown. The mapping uses an effective algorithm linking biomass to measured spectral reflectance and a means to correct the scanner data for large variations in the angle of observation of the canopy. The consistency of radiometric biomass algorithms for marsh grass when they are applied over large latitudinal and tidal range gradients were also examined. Results of a 1 year study of methane emissions from tidal wetlands along a salinity gradient show marked effects of temperature, season, and pore-water chemistry in mediating flux to the atmosphere.

Charge-Transfer Analysis of 2p3d Resonant Inelastic X-ray Scattering of Cobalt Sulfide and Halides

PubMed Central

2017-01-01

We show that with 2p3d resonant inelastic X-ray scattering (RIXS) we can accurately determine the charge-transfer parameters of CoF2, CoCl2, CoBr2, and CoS. The 160 meV resolution RIXS results are compared with charge-transfer multiplet calculations. The improved resolution and the direct observation of the crystal field and charge-transfer excitations allow the determination of more accurate parameters than could be derived from X-ray absorption and X-ray photoemission, both limited in resolution by their lifetime broadening. We derive the crystal field and charge-transfer parameters of the Co2+ ions, which provides the nature of the ground state of the Co2+ ions with respect to symmetry and hybridization. In addition, the increased spectral resolution allows the more accurate determination of the atomic Slater integrals. The results show that the crystal field energy decreases with increasing ligand covalency. The L2 edge RIXS spectra show that the intensity of the (Coster–Kronig induced) nonresonant X-ray emission is a measure of ligand covalency. PMID:29170686

Iterative optimization method for design of quantitative magnetization transfer imaging experiments.

PubMed

Levesque, Ives R; Sled, John G; Pike, G Bruce

2011-09-01

Quantitative magnetization transfer imaging (QMTI) using spoiled gradient echo sequences with pulsed off-resonance saturation can be a time-consuming technique. A method is presented for selection of an optimum experimental design for quantitative magnetization transfer imaging based on the iterative reduction of a discrete sampling of the Z-spectrum. The applicability of the technique is demonstrated for human brain white matter imaging at 1.5 T and 3 T, and optimal designs are produced to target specific model parameters. The optimal number of measurements and the signal-to-noise ratio required for stable parameter estimation are also investigated. In vivo imaging results demonstrate that this optimal design approach substantially improves parameter map quality. The iterative method presented here provides an advantage over free form optimal design methods, in that pragmatic design constraints are readily incorporated. In particular, the presented method avoids clustering and repeated measures in the final experimental design, an attractive feature for the purpose of magnetization transfer model validation. The iterative optimal design technique is general and can be applied to any method of quantitative magnetization transfer imaging. Copyright © 2011 Wiley-Liss, Inc.

Modelling the Impact of Life on Continental Growth - Mechanisms and Results

NASA Astrophysics Data System (ADS)

Höning, D.; Spohn, T.

2013-12-01

The complexity of planetary evolution increases with the number of interacting reservoirs. On Earth, even the biosphere is speculated to interact with the interior. It has been argued (e.g., Rosing et al. 2006; Sleep et al, 2012) that the formation of continents could be a consequence of bioactivity harvesting solar energy through photosynthesis to help build the continents and that the mantle should carry a chemical biosignature. Through plate tectonics, the surface biosphere can impact deep subduction zone processes and the interior of the Earth. Subducted sediments are particularly important, because they influence the Earth's interior in several ways, and in turn are strongly influenced by the Earth's biosphere. In our model, we use the assumption that a thick sedimentary layer of low permeability on top of the subducting oceanic crust, caused by a biologically enhanced weathering rate, can suppress shallow dewatering. This in turn leads to greater availability of water in the source region of andesitic partial melt, resulting in an enhanced rate of continental production and regassing rate into the mantle. Our model includes (i) mantle convection, (ii) continental erosion and production, and (iii) mantle water degassing at mid-ocean ridges and regassing at subduction zones. The mantle viscosity of our model depends on (i) the mantle water concentration and (ii) the mantle temperature, whose time dependency is given by radioactive decay of isotopes in the Earth's mantle. Boundary layer theory yields the speed of convection and the water outgassing rate of the Earth's mantle. Our results indicate that present day values of continental surface area and water content of the Earth's mantle represent an attractor in a phase plane spanned by both parameters. We show that the biologic enhancement of the continental erosion rate is important for the system to reach this fixed point. An abiotic Earth tends to reach an alternative stable fixed point with a smaller continental surface area and dryer mantle. The origin and evolution of life on Earth might be responsible for the rise of continents 3.5 billion years ago. References: [1] N. H. Sleep et al., Annu. Rev. Earth Planet. Sci. 40, 277-300, 2012 [2] M. T. Rosing et al., Paleo3 232, 90-113, 2006

Magnetohydrodynamics effect on convective boundary layer flow and heat transfer of viscoelastic micropolar fluid past a sphere

NASA Astrophysics Data System (ADS)

Amera Aziz, Laila; Kasim, Abdul Rahman Mohd; Zuki Salleh, Mohd; Syahidah Yusoff, Nur; Shafie, Sharidan

2017-09-01

The main interest of this study is to investigate the effect of MHD on the boundary layer flow and heat transfer of viscoelastic micropolar fluid. Governing equations are transformed into dimensionless form in order to reduce their complexity. Then, the stream function is applied to the dimensionless equations to produce partial differential equations which are then solved numerically using the Keller-box method in Fortran programming. The numerical results are compared to published study to ensure the reliability of present results. The effects of selected physical parameters such as the viscoelastic parameter, K, micropolar parameter, K1 and magnetic parameter, M on the flow and heat transfer are discussed and presented in tabular and graphical form. The findings from this study will be of critical importance in the fields of medicine, chemical as well as industrial processes where magnetic field is involved.

Probing Reliability of Transport Phenomena Based Heat Transfer and Fluid Flow Analysis in Autogeneous Fusion Welding Process

NASA Astrophysics Data System (ADS)

Bag, S.; de, A.

2010-09-01

The transport phenomena based heat transfer and fluid flow calculations in weld pool require a number of input parameters. Arc efficiency, effective thermal conductivity, and viscosity in weld pool are some of these parameters, values of which are rarely known and difficult to assign a priori based on the scientific principles alone. The present work reports a bi-directional three-dimensional (3-D) heat transfer and fluid flow model, which is integrated with a real number based genetic algorithm. The bi-directional feature of the integrated model allows the identification of the values of a required set of uncertain model input parameters and, next, the design of process parameters to achieve a target weld pool dimension. The computed values are validated with measured results in linear gas-tungsten-arc (GTA) weld samples. Furthermore, a novel methodology to estimate the overall reliability of the computed solutions is also presented.

Heat and Mass Transfer in an L Shaped Porous Medium

NASA Astrophysics Data System (ADS)

Salman Ahmed, N. J.; Azeem; Yunus Khan, T. M.

2017-08-01

This article is an extension to the heat transfer in L-shaped porous medium by including the mass diffusion. The heat and mass transfer in the porous domain is represented by three coupled partial differential equations representing the fluid movement, energy transport and mass transport. The equations are converted into algebraic form of equations by the application of finite element method that can be conveniently solved by matrix method. An iterative approach is adopted to solve the coupled equations by setting suitable convergence criterion. The results are discussed in terms of heat transfer characteristics influenced by physical parameters such as buoyancy ratio, Lewis number, Rayleigh number etc. It is found that these physical parameters have significant effect on heat and mass transfer behavior of L-shaped porous medium.

Human impact on the planet: an earth system science perspective and ethical considerations

USGS Publications Warehouse

Williams, Richard S.

2002-01-01

The modern Earth Narrative, the scientific story of the 4.5 billion-year natural and human history of the Earth, has emerged from the solid foundation of two factual concepts: Deep (or Geologic) Time and Biological Evolution. spread acceptance of the Earth Narrative is critically important as we begin the third millennium, because it provides a clear understanding of the growing impact of human population growth and associated activities on the Earth System, especially the negative impact on Earth?s biosphere. It is important for humans to realize that we are but one of 4,500 species of mammals that exist on Earth and that we are but one species in the estimated 30 to 100 million species that form the complex biosphere. We also need to recognize that all species exist within the physical limits imposed by the geosphere. We are totally dependent on the biosphere for food, oxygen, and other necessities of life. mans are one of the latest results of biological evolution operating over a long period of Geologic Time. We find ourselves on Earth, after 4.5 billion years of Earth history by chance, not by design. Humans have become so successful at modifying their environment that many of the natural limitations on the expansion of populations of our fellow animals have been overcome by technological and cultural innovations. According to Peter Raven, ?Humans, at a current population of 6 billion [expected to nearly double by 2050], are consuming or wasting about 50 percent of the total net biological productivity on land and 50 percent of the available supply of freshwater. The overwhelming and expanding human presence leaves less and less room in the environment for other biota.? st century will be a pivotal time in the fate of Earth?s biosphere. Whereas human modification of the geosphere will slowly recover over time, human changes to the biosphere are a far more consequential matter? extinction of a species is forever! Will humans effectively use our new knowledge of natural and human history to stop further degradation of Earth?s ecosystems and extinction of its biota? The fate of the biosphere, including humanity, depends on a reaffirmation by all humans of all cultures and religions of the global importance of a planet-wide conservation of the Earth?s biotic heritage. For the world?s religions it means elevation of stewardship of the Earth to a moral imperative and a goal of complete preservation of the Earth?s biotic inheritance, one which is based on a Do No Harm ethic.

Using observations to evaluate biosphere-atmosphere interactions in models

NASA Astrophysics Data System (ADS)

Green, Julia; Konings, Alexandra G.; Alemohammad, Seyed H.; Gentine, Pierre

2017-04-01

Biosphere-atmosphere interactions influence the hydrologic cycle by altering climate and weather patterns (Charney, 1975; Koster et al., 2006; Seneviratne et al., 2006), contributing up to 30% of precipitation and radiation variability in certain regions (Green et al., 2017). They have been shown to contribute to the persistence of drought in Europe (Seneviratne et al., 2006), as well as to increase rainfall in the Amazon (Spracklen et al., 2012). Thus, a true representation of these feedbacks in Earth System Models (ESMs) is crucial for accurate forecasting and planning. However, it has been difficult to validate the performance of ESMs since often-times surface and atmospheric flux data are scarce and/or difficult to observe. In this study, we use the results of a new global observational study (using remotely sensed solar-induced fluorescence to represent the biosphere flux) (Green et al., 2017) to determine how well a suite of 13 ESMs capture biosphere-atmosphere feedbacks. We perform a Conditional Multivariate Granger Causality analysis in the frequency domain with radiation, precipitation and temperature as atmospheric inputs and GPP as the biospheric input. Performing the analysis in the frequency domain allows for separation of feedbacks at different time-scales (subseasonal, seasonal or interannual). Our findings can be used to determine whether there is agreement between models, as well as, to pinpoint regions or time-scales of model bias or inaccuracy, which will provide insight on potential improvement. We demonstrate that in addition to the well-known problem of convective parameterization over land in models, the main issue in representing feedbacks between the land and the atmosphere is due to the misrepresentation of water stress. These results provide a direct quantitative assessment of feedbacks in models and how to improve them. References: Charney, J.G. Dynamics of deserts and drought in the Sahel. Quarterly Journal of the Royal Meteorological Society 101, 193-202 (1975). Green, J.K., Konings, A.G., Alemohammad, S.H., Berry, J., Entekhabi, D., Kolassa, J., Lee, J.E., Gentine, P. Hotspots of terrestrial biosphere-atmosphere feedbacks. In review. (2017). Koster, R. D. et al. GLACE: The Global Land - Atmosphere Coupling Experiment. Part I: Overview. J. Hydrometeorol. 7, 611-625 (2006). Seneviratne, S.I., Lüthi, D., Litschi M., Schär, C. Land-atmosphere coupling and climate change in Europe. Nature 443, 205-209 (2006). Spracklen, D.V, Arnold, S.R., Taylor, C.M. Observations of increased tropical rainfall preceded by air passage over forests. Nature 489, 282-285 (2012).

Earth's Early Biosphere and the Biogeochemical Carbon Cycle

NASA Technical Reports Server (NTRS)

DesMarais, David

2004-01-01

Our biosphere has altered the global environment principally by influencing the chemistry of those elements most important for life, e g., C, N, S, O, P and transition metals (e.g., Fe and Mn). The coupling of oxygenic photosynthesis with the burial in sediments of photosynthetic organic matter, and with the escape of H2 to space, has increased the state of oxidation of the Oceans and atmosphere. It has also created highly reduced conditions within sedimentary rocks that have also extensively affected the geochemistry of several elements. The decline of volcanism during Earth's history reduced the flow of reduced chemical species that reacted with photosynthetically produced O2. The long-term net accumulation of photosynthetic O2 via biogeochemical processes has profoundly influenced our atmosphere and biosphere, as evidenced by the O2 levels required for algae, multicellular life and certain modem aerobic bacteria to exist. When our biosphere developed photosynthesis, it tapped into an energy resource that was much larger than the energy available from oxidation-reduction reactions associated with weathering and hydrothermal activity. Today, hydrothermal sources deliver globally (0.13-1.1)x10(exp l2) mol yr(sup -1) of reduced S, Fe(2+), Mn(2+), H2 and CH4; this is estimated to sustain at most about (0.2-2)xl0(exp 12)mol C yr(sup -1) of organic carbon production by chemautotrophic microorganisms. In contrast, global photosynthetic productivity is estimated to be 9000x10(exp 12) mol C yr(sup -1). Thus, even though global thermal fluxes were greater in the distant geologic past than today, the onset of oxygenic photosynthesis probably increased global organic productivity by some two or more orders of magnitude. This enormous productivity materialized principally because oxygenic photosynthesizers unleashed a virtually unlimited supply of reduced H that forever freed life from its sole dependence upon abiotic sources of reducing power such as hydrothermal emanations and weathering. Communities sustained by oxygenic photosynthesis apparently thrived wherever supplies of sunlight, moisture and nutrients were sufficient. Prior to the development of oxygenic photosynthesis, the net global effect of the ancient global biosphere was to facilitate chemical equilibrium between reduced species from thermal activity and weathering and more oxidized constituents in the surface environment. But even this ancient biosphere might have been globally pervasive. The global geothermal heat flow was substantially higher during Earth's first billion years, and thus reduced chemical species might have persisted in sunlit aquatic environments. Perhaps the substantial decline in thermal activity between 4000 and 3000 Ma created a driver for oxygenic photosynthesis to develop.

Convection Heat and Mass Transfer in a Power Law Fluid with Non Constant Relaxation Time Past a Vertical Porous Plate in the Presence of Thermo and Thermal Diffusion

NASA Astrophysics Data System (ADS)

Olajuwon, B. I.; Oyelakin, I. S.

2012-12-01

The paper investigates convection heat and mass transfer in power law fluid flow with non relaxation time past a vertical porous plate in presence of a chemical reaction, heat generation, thermo diffu- sion and thermal diffusion. The non - linear partial differential equations governing the flow are transformed into ordinary differential equations using the usual similarity method. The resulting similarity equations are solved numerically using Runge-Kutta shooting method. The results are presented as velocity, temperature and concentration profiles for pseudo plastic fluids and for different values of parameters governing the prob- lem. The skin friction, heat transfer and mass transfer rates are presented numerically in tabular form. The results show that these parameters have significant effects on the flow, heat transfer and mass transfer.

Sea spray aerosol structure and composition using cryogenic transmission electron microscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patterson, Joseph P.; Collins, Douglas B.; Michaud, Jennifer M.

The surface properties of atmospheric aerosol particles largely control their impact on climate by affecting their ability to uptake water, react heterogeneously, and nucleate ice in clouds. However, in the vacuum of a conventional electron microscope, the native surface structure often undergoes chemical rearrangement resulting in surfaces that are quite different from their atmospheric configurations. Herein, we report the development of a cryo-TEM approach where sea spray aerosol particles are flash frozen in their native state and then probed by electron microscopy. This unique approach allows for the detection of not only mixed salts, but also soft materials including wholemore » hydrated bacteria, diatoms, virus particles, marine vesicles, as well as gel networks within hydrated salt droplets. As a result, we anticipate this method will open up a new avenue of analysis for aerosol particles, not only for ocean-derived aerosols, but for those produced from other sources where there is interest in the transfer of organic or biological species from the biosphere to the atmosphere.« less

Sea spray aerosol structure and composition using cryogenic transmission electron microscopy

DOE PAGES

Patterson, Joseph P.; Collins, Douglas B.; Michaud, Jennifer M.; ...

2016-01-15

The surface properties of atmospheric aerosol particles largely control their impact on climate by affecting their ability to uptake water, react heterogeneously, and nucleate ice in clouds. However, in the vacuum of a conventional electron microscope, the native surface structure often undergoes chemical rearrangement resulting in surfaces that are quite different from their atmospheric configurations. Herein, we report the development of a cryo-TEM approach where sea spray aerosol particles are flash frozen in their native state and then probed by electron microscopy. This unique approach allows for the detection of not only mixed salts, but also soft materials including wholemore » hydrated bacteria, diatoms, virus particles, marine vesicles, as well as gel networks within hydrated salt droplets. As a result, we anticipate this method will open up a new avenue of analysis for aerosol particles, not only for ocean-derived aerosols, but for those produced from other sources where there is interest in the transfer of organic or biological species from the biosphere to the atmosphere.« less

Arterial pressure transfer characteristics: effects of travel time.

PubMed

Westerhof, Berend E; Guelen, Ilja; Stok, Wim J; Wesseling, Karel H; Spaan, Jos A E; Westerhof, Nico; Bos, Willem Jan; Stergiopulos, Nikos

2007-02-01

We investigated the quantitative contribution of all local conduit arterial, blood, and distal load properties to the pressure transfer function from brachial artery to aorta. The model was based on anatomical data, Young's modulus, wall viscosity, blood viscosity, and blood density. A three-element windkessel represented the distal arterial tree. Sensitivity analysis was performed in terms of frequency and magnitude of the peak of the transfer function and in terms of systolic, diastolic, and pulse pressure in the aorta. The root mean square error (RMSE) described the accuracy in wave-shape prediction. The percent change of these variables for a 25% alteration of each of the model parameters was calculated. Vessel length and diameter are found to be the most important parameters determining pressure transfer. Systolic and diastolic pressure changed <3% and RMSE <1.8 mmHg for a 25% change in vessel length and diameter. To investigate how arterial tapering influences the pressure transfer, a single uniform lossless tube was modeled. This simplification introduced only small errors in systolic and diastolic pressures (1% and 0%, respectively), and wave shape was less well described (RMSE, approximately 2.1 mmHg). Local (arm) vasodilation affects the transfer function little, because it has limited effect on the reflection coefficient. Since vessel length and diameter translate into travel time, this parameter can describe the transfer accurately. We suggest that with a, preferably, noninvasively measured travel time, an accurate individualized description of pressure transfer can be obtained.

MHD Forced Convective Laminar Boundary Layer Flow from a Convectively Heated Moving Vertical Plate with Radiation and Transpiration Effect

PubMed Central

Uddin, Md. Jashim; Khan, Waqar A.; Ismail, A. I. Md.

2013-01-01

A two-dimensional steady forced convective flow of a Newtonian fluid past a convectively heated permeable vertically moving plate in the presence of a variable magnetic field and radiation effect has been investigated numerically. The plate moves either in assisting or opposing direction to the free stream. The plate and free stream velocities are considered to be proportional to whilst the magnetic field and mass transfer velocity are taken to be proportional to where is the distance along the plate from the leading edge of the plate. Instead of using existing similarity transformations, we use a linear group of transformations to transform the governing equations into similarity equations with relevant boundary conditions. Numerical solutions of the similarity equations are presented to show the effects of the controlling parameters on the dimensionless velocity, temperature and concentration profiles as well as on the friction factor, rate of heat and mass transfer. It is found that the rate of heat transfer elevates with the mass transfer velocity, convective heat transfer, Prandtl number, velocity ratio and the magnetic field parameters. It is also found that the rate of mass transfer enhances with the mass transfer velocity, velocity ratio, power law index and the Schmidt number, whilst it suppresses with the magnetic field parameter. Our results are compared with the results existing in the open literature. The comparisons are satisfactory. PMID:23741295

Tuning a physically-based model of the air-sea gas transfer velocity

NASA Astrophysics Data System (ADS)

Jeffery, C. D.; Robinson, I. S.; Woolf, D. K.

Air-sea gas transfer velocities are estimated for one year using a 1-D upper-ocean model (GOTM) and a modified version of the NOAA-COARE transfer velocity parameterization. Tuning parameters are evaluated with the aim of bringing the physically based NOAA-COARE parameterization in line with current estimates, based on simple wind-speed dependent models derived from bomb-radiocarbon inventories and deliberate tracer release experiments. We suggest that A = 1.3 and B = 1.0, for the sub-layer scaling parameter and the bubble mediated exchange, respectively, are consistent with the global average CO 2 transfer velocity k. Using these parameters and a simple 2nd order polynomial approximation, with respect to wind speed, we estimate a global annual average k for CO 2 of 16.4 ± 5.6 cm h -1 when using global mean winds of 6.89 m s -1 from the NCEP/NCAR Reanalysis 1 1954-2000. The tuned model can be used to predict the transfer velocity of any gas, with appropriate treatment of the dependence on molecular properties including the strong solubility dependence of bubble-mediated transfer. For example, an initial estimate of the global average transfer velocity of DMS (a relatively soluble gas) is only 11.9 cm h -1 whilst for less soluble methane the estimate is 18.0 cm h -1.

Locally optimal transfer trajectories between libration point orbits using invariant manifolds

NASA Astrophysics Data System (ADS)

Davis, Kathryn E.

2009-12-01

Techniques from dynamical systems theory and primer vector theory have been applied to the construction of locally optimal transfer trajectories between libration point orbits. When two libration point orbits have different energies, it has been found that the unstable manifold of the first orbit can be connected to the stable manifold of the second orbit with a bridging trajectory. A bounding sphere centered on the secondary, with a radius less than the radius of the sphere of influence of the secondary, was used to study the stable and unstable manifold trajectories. It was numerically demonstrated that within the bounding sphere, the two-body parameters of the unstable and stable manifold trajectories could be analyzed to locate low transfer costs. It was shown that as the two-body parameters of an unstable manifold trajectory more closely matched the two-body parameters of a stable manifold trajectory, the total DeltaV necessary to complete the transfer decreased. Primer vector theory was successfully applied to a transfer to determine the optimal maneuvers required to create the bridging trajectory that connected the unstable manifold of the first orbit to the stable manifold of the second orbit. Transfer trajectories were constructed between halo orbits in the Sun-Earth and Earth-Moon three-body systems. Multiple solutions were found between the same initial and final orbits, where certain solutions retraced interior portions of the trajectory. All of the trajectories created satisfied the conditions for optimality. The costs of transfers constructed using invariant manifolds were compared to the costs of transfers constructed without the use of invariant manifolds, when data was available. In all cases, the total cost of the transfers were significantly lower when invariant manifolds were used in the transfer construction. In many cases, the transfers that employed invariant manifolds were three to four times more efficient, in terms of fuel expenditure, than the transfer that did not. The decrease in transfer cost was accompanied by an increase in transfer time of flight. Transfers constructed in the Earth-Moon system were shown to be particularly viable for lunar navigation and communication constellations, as excellent coverage of the lunar surface can be achieved during the transfer.

Managing Environmental Stress: An Evaluation of Environmental Management of the Long Point Sandy Barrier, Lake Erie, Canada.

PubMed

Kreutzwiser; Gabriel

2000-01-01

/ This paper assesses the extent to which key geomorphic components, processes, and stresses have been reflected in the management of a coastal sandy barrier environment. The management policies and practices of selected agencies responsible for Long Point, a World Biosphere Reserve along Lake Erie, Canada, were evaluated for consistency with these principles of environmental management for sandy barriers: maintaining natural stresses essential to sandy barrier development and maintenance;protecting sediment sources, transfers, and storage; recognizing spatial variability and cyclicity of natural stresses, such as barrier overwash events; and accepting and planning for long-term evolutionary changes in the sandy barrier environment. Generally, management policies and practices have not respected the dynamic and sensitive environment of Long Point because of limited mandates of the agencies involved, inconsistent policies, and failure to apply or enforce existing policies. This is particularly evident with local municipalities and less so for the Canadian Wildlife Service, the federal agency responsible for managing National Wildlife Areas at the point. In the developed areas of Long Point, landward sediment transfers and sediment storage in dunes have been impacted by cottage development, shore protection, and maintenance of roads and parking lots. Additionally, agencies responsible for managing Long Point have no jurisdiction over sediment sources as far as 95 km away. Evolutionary change of sandy barriers poses the greatest challenge to environmental managers.

Influence of bacteria on lanthanide and actinide transfer from specific soil components (humus, soil minerals and vitrified municipal solid waste incinerator bottom ash) to corn plants: Sr-Nd isotope evidence.

PubMed

Aouad, Georges; Stille, Peter; Crovisier, Jean-Louis; Geoffroy, Valérie A; Meyer, Jean-Marie; Lahd-Geagea, Majdi

2006-11-01

Experiments have been performed to test the stability of vitrified municipal solid waste (MSW) incinerator bottom ash under the presence of bacteria (Pseudomonas aeruginosa) and plants (corn). The substratum used for the plant growth was a humus-rich soil mixed with vitrified waste. For the first time, information on the stability of waste glasses in the presence of bacteria and plants is given. Results show that inoculated plant samples contained always about two times higher lanthanide and actinide element concentrations. Bacteria support the element transfer since plants growing in inoculated environment developed a smaller root system but have higher trace element concentrations. Compared with the substratum, plants are light rare earth element (LREE) enriched. The vitrified bottom ash has to some extent been corroded by bacteria and plant activities as indicated by the presence of Nd (REE) and Sr from the vitrified waste in the plants. (87)Sr/(86)Sr and (143)Nd/(144)Nd isotope ratios of plants and soil components allow the identification of the corroded soil components and confirm that bacteria accelerate the assimilation of elements from the vitrified bottom ash. These findings are of importance for landfill disposal scenarios, and similar experiments should be performed in order to better constrain the processes of microbially mediated alteration of the MSW glasses in the biosphere.

Orthoptera (Insecta: Tettigonioidea, Pyrgomorphoidea, Acridoidea) of Kafa Biosphere Reserve, Bale Mountains National Park and other areas of conservation interest in Ethiopia.

PubMed

Felix, Rob P W H; Massa, Bruno

2016-11-09

An annotated checklist of 51 Orthoptera taxa (Tettigonioidea, Pyrgomorphoidea and Acridoidea) of Kafa Biosphere Reserve, Bale Mountains National Park and some additional sites in Ethiopia is presented. Ten species are newly recorded for the country. Four species are new to science: Peropyrrhicia attilioi n. sp., P. keffensis n. sp., P. semiensis n. sp. and Coryphosima danieli n. sp. The status of Peropyrrhicia cooperi Uvarov, 1934 and P. scotti Uvarov, 1934 is revised: both are considered valid species.

The biosphere as a driver of global atmospheric change

NASA Technical Reports Server (NTRS)

Levine, Joel S.

1991-01-01

The effects of the biosphere on the evolution of atmospheric oxygen and ozone, and the consequences of that development for global atmospheric change, are discussed. Attention is given to the impact of oxygen and ozone on atmospheric photolysis rates, the effect of oxygen on the biogenic production of nitrous oxide and nitric oxide, and the effects of the evolution of atmospheric oxygen on fires and biomass burning. The influence of the latter on atmospheric processes, particularly the production of methane, carbon dioxide, and carbon monoxide, is considered.

Symbolic Regression for the Estimation of Transfer Functions of Hydrological Models

NASA Astrophysics Data System (ADS)

Klotz, D.; Herrnegger, M.; Schulz, K.

2017-11-01

Current concepts for parameter regionalization of spatially distributed rainfall-runoff models rely on the a priori definition of transfer functions that globally map land surface characteristics (such as soil texture, land use, and digital elevation) into the model parameter space. However, these transfer functions are often chosen ad hoc or derived from small-scale experiments. This study proposes and tests an approach for inferring the structure and parametrization of possible transfer functions from runoff data to potentially circumvent these difficulties. The concept uses context-free grammars to generate possible proposition for transfer functions. The resulting structure can then be parametrized with classical optimization techniques. Several virtual experiments are performed to examine the potential for an appropriate estimation of transfer function, all of them using a very simple conceptual rainfall-runoff model with data from the Austrian Mur catchment. The results suggest that a priori defined transfer functions are in general well identifiable by the method. However, the deduction process might be inhibited, e.g., by noise in the runoff observation data, often leading to transfer function estimates of lower structural complexity.

Stagnation Region Heat Transfer: The Influence of Turbulence Parameters, Reynolds Number and Body Shape

NASA Technical Reports Server (NTRS)

Vanfossen, G. James; Simoneau, Robert J.

1994-01-01

The effect of velocity gradient on stagnation region heat transfer augmentation by free stream turbulence was investigated. Heat transfer was measured in the stagnation region of four models with elliptical leading edges with ratios of major to minor axes of 1:1, 1.5:1, 2.25:1, and 3:1. Four geometrically similar, square bar, square mesh, biplane grids were used to generate free stream turbulence with different intensities and length. Heat transfer measurements were made for the following ranges of parameters: Reynolds number, based on leading edge diameter, 37,000 to 228,000; dimensionless leading edge velocity gradient, 1.20 to 1.80; turbulence intensity, 1.1 to 15.9%; and length scale to leading edge diameter ratio, 0.05 to 0.30. Stagnation point heat transfer augmentation by free stream turbulence can be predicted using a modified version of a previously developed correlation for a circular leading edge. Heat transfer augmentation was independent of body shape at the stagnation point. The heat transfer distribution down-stream from the stagnation point can be predicted using the normalized laminar heat transfer distribution.

Förster-type energy transfer as a probe for changes in local fluctuations of the protein matrix.

PubMed

Somogyi, B; Matkó, J; Papp, S; Hevessy, J; Welch, G R; Damjanovich, S

1984-07-17

Much evidence, on both theoretical and experimental sides, indicates the importance of local fluctuations (in energy levels, conformational substates, etc.) of the macromolecular matrix in the biological activity of proteins. We describe here a novel application of the Förster-type energy-transfer process capable of monitoring changes both in local fluctuations and in conformational states of macromolecules. A new energy-transfer parameter, f, is defined as an average transfer efficiency, [E], normalized by the actual average quantum efficiency of the donor fluorescence, [phi D]. A simple oscillator model (for a one donor-one acceptor system) is presented to show the sensitivity of this parameter to changes in amplitudes of local fluctuations. The different modes of averaging (static, dynamic, and intermediate cases) occurring for a given value of the average transfer rate, [kt], and the experimental requirements as well as limitations of the method are also discussed. The experimental tests were performed on the ribonuclease T1-pyridoxamine 5'-phosphate conjugate (a one donor-one acceptor system) by studying the change of the f parameter with temperature, an environmental parameter expectedly perturbing local fluctuations of proteins. The parameter f increased with increasing temperature as expected on the basis of the oscillator model, suggesting that it really reflects changes of fluctuation amplitudes (significant changes in the orientation factor, k2, as well as in the spectral properties of the fluorophores can be excluded by anisotropy measurements and spectral investigations). Possibilities of the general applicability of the method are also discussed.

A scale self-adapting segmentation approach and knowledge transfer for automatically updating land use/cover change databases using high spatial resolution images

NASA Astrophysics Data System (ADS)

Wang, Zhihua; Yang, Xiaomei; Lu, Chen; Yang, Fengshuo

2018-07-01

Automatic updating of land use/cover change (LUCC) databases using high spatial resolution images (HSRI) is important for environmental monitoring and policy making, especially for coastal areas that connect the land and coast and that tend to change frequently. Many object-based change detection methods are proposed, especially those combining historical LUCC with HSRI. However, the scale parameter(s) segmenting the serial temporal images, which directly determines the average object size, is hard to choose without experts' intervention. And the samples transferred from historical LUCC also need experts' intervention to avoid insufficient or wrong samples. With respect to the scale parameter(s) choosing, a Scale Self-Adapting Segmentation (SSAS) approach based on the exponential sampling of a scale parameter and location of the local maximum of a weighted local variance was proposed to determine the scale selection problem when segmenting images constrained by LUCC for detecting changes. With respect to the samples transferring, Knowledge Transfer (KT), a classifier trained on historical images with LUCC and applied in the classification of updated images, was also proposed. Comparison experiments were conducted in a coastal area of Zhujiang, China, using SPOT 5 images acquired in 2005 and 2010. The results reveal that (1) SSAS can segment images more effectively without intervention of experts. (2) KT can also reach the maximum accuracy of samples transfer without experts' intervention. Strategy SSAS + KT would be a good choice if the temporal historical image and LUCC match, and the historical image and updated image are obtained from the same resource.

How Do Radionuclides Accumulate in Marine Organisms? A Case Study of Europium with Aplysina cavernicola

DOE PAGES

Maloubier, Melody; Shuh, David K.; Minasian, Stefan G.; ...

2016-09-15

In the ocean, complex interactions between natural and anthropogenic radionuclides, seawater, and diverse marine biota provide a unique window through which to examine ecosystem and trophic transfer mechanisms in cases of accidental dissemination. The nature of interaction between radionuclides, the marine environment, and marine species is therefore essential for better understanding transfer mechanisms from the hydrosphere to the biosphere. Although data pertaining to the rate of global transfer are often available, little is known regarding the mechanism of environmental transport and uptake of heavy radionuclides by marine species. Among marine species, sponges are immobile active filter feeders and have beenmore » identified as hyperaccumulators of several heavy metals. We have selected the Mediterranean sponge Aplysina cavernicola as a model species for this study. Actinide elements are not the only source of radioactive release in cases of civilian nuclear events; however, their physicochemical transfer mechanisms to marine species remain largely unknown. We have targeted europium(III) as a representative of the trivalent actinides such as americium or curium. To unravel biological uptake mechanisms of europium in A. cavernicola, we have combined radiometric (γ) measurements with spectroscopic (time-resolved laser-induced fluorescence spectroscopy, TRLIFS, and X-ray absorption near-edge structure, XANES) and imaging (transmission electron microscopy, TEM, and scanning transmission X-ray microscopy, STXM) techniques. Here, we have observed that the colloids of NaEu(CO 3) 2 ·nH 2O formed in seawater are taken up by A. cavernicola with no evidence that lethal dose has been reached in our working conditions. Spectroscopic results suggest that there is no change of speciation during uptake. Finally, TEM and STXM images recorded at different locations across a sponge cross section, together with differential cell separation, indicate the presence of europium particles (around 200 nm) mainly located in the skeleton and toward the outer surface of the sponge.« less

How Do Radionuclides Accumulate in Marine Organisms? A Case Study of Europium with Aplysina cavernicola

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maloubier, Melody; Shuh, David K.; Minasian, Stefan G.

In the ocean, complex interactions between natural and anthropogenic radionuclides, seawater, and diverse marine biota provide a unique window through which to examine ecosystem and trophic transfer mechanisms in cases of accidental dissemination. The nature of interaction between radionuclides, the marine environment, and marine species is therefore essential for better understanding transfer mechanisms from the hydrosphere to the biosphere. Although data pertaining to the rate of global transfer are often available, little is known regarding the mechanism of environmental transport and uptake of heavy radionuclides by marine species. Among marine species, sponges are immobile active filter feeders and have beenmore » identified as hyperaccumulators of several heavy metals. We have selected the Mediterranean sponge Aplysina cavernicola as a model species for this study. Actinide elements are not the only source of radioactive release in cases of civilian nuclear events; however, their physicochemical transfer mechanisms to marine species remain largely unknown. We have targeted europium(III) as a representative of the trivalent actinides such as americium or curium. To unravel biological uptake mechanisms of europium in A. cavernicola, we have combined radiometric (γ) measurements with spectroscopic (time-resolved laser-induced fluorescence spectroscopy, TRLIFS, and X-ray absorption near-edge structure, XANES) and imaging (transmission electron microscopy, TEM, and scanning transmission X-ray microscopy, STXM) techniques. Here, we have observed that the colloids of NaEu(CO 3) 2 ·nH 2O formed in seawater are taken up by A. cavernicola with no evidence that lethal dose has been reached in our working conditions. Spectroscopic results suggest that there is no change of speciation during uptake. Finally, TEM and STXM images recorded at different locations across a sponge cross section, together with differential cell separation, indicate the presence of europium particles (around 200 nm) mainly located in the skeleton and toward the outer surface of the sponge.« less

Temporal variations of atmospheric CO2 and CO at Ahmedabad in western India

NASA Astrophysics Data System (ADS)

Chandra, Naveen; Lal, Shyam; Venkataramani, S.; Patra, Prabir K.; Sheel, Varun

2016-05-01

About 70 % of the anthropogenic carbon dioxide (CO2) is emitted from the megacities and urban areas of the world. In order to draw effective emission mitigation policies for combating future climate change as well as independently validating the emission inventories for constraining their large range of uncertainties, especially over major metropolitan areas of developing countries, there is an urgent need for greenhouse gas measurements over representative urban regions. India is a fast developing country, where fossil fuel emissions have increased dramatically in the last three decades and are predicted to continue to grow further by at least 6 % per year through to 2025. The CO2 measurements over urban regions in India are lacking. To overcome this limitation, simultaneous measurements of CO2 and carbon monoxide (CO) have been made at Ahmedabad, a major urban site in western India, using a state-of-the-art laser-based cavity ring down spectroscopy technique from November 2013 to May 2015. These measurements enable us to understand the diurnal and seasonal variations in atmospheric CO2 with respect to its sources (both anthropogenic and biospheric) and biospheric sinks. The observed annual average concentrations of CO2 and CO are 413.0 ± 13.7 and 0.50 ± 0.37 ppm respectively. Both CO2 and CO show strong seasonality with lower concentrations (400.3 ± 6.8 and 0.19 ± 0.13 ppm) during the south-west monsoon and higher concentrations (419.6 ± 22.8 and 0.72 ± 0.68 ppm) during the autumn (SON) season. Strong diurnal variations are also observed for both the species. The common factors for the diurnal cycles of CO2 and CO are vertical mixing and rush hour traffic, while the influence of biospheric fluxes is also seen in the CO2 diurnal cycle. Using CO and CO2 covariation, we differentiate the anthropogenic and biospheric components of CO2 and found significant contributions of biospheric respiration and anthropogenic emissions in the late night (00:00-05:00 h, IST) and evening rush hours (18:00-22:00 h) respectively. We compute total yearly emissions of CO to be 69.2 ± 0.07 Gg for the study region using the observed CO : CO2 correlation slope and bottom-up CO2 emission inventory. This calculated emission of CO is 52 % larger than the estimated emission of CO by the emissions database for global atmospheric research (EDGAR) inventory. The observations of CO2 have been compared with an atmospheric chemistry-transport model (ACTM), which incorporates various components of CO2 fluxes. ACTM is able to capture the basic variabilities, but both diurnal and seasonal amplitudes are largely underestimated compared to the observations. We attribute this underestimation by the model to uncertainties in terrestrial biosphere fluxes and coarse model resolution. The fossil fuel signal from the model shows fairly good correlation with observed CO2 variations, which supports the overall dominance of fossil fuel emissions over the biospheric fluxes in this urban region.

New procedure for recovering extra- and intracellular DNA from marine sediment samples

NASA Astrophysics Data System (ADS)

Alawi, M.; Kallmeyer, J.

2012-12-01

Extracellular DNA (eDNA) is a ubiquitous biological compound in aquatic sediment and soil. Despite major methodological advances, analysis of DNA from sediment is still technically challenging, not just because of the co-elution of inhibitory substances, but also due to co-elution of extracellular DNA, which potentially leads to an overestimate of the actual diversity. Previous studies suggested that eDNA might play an important role in biogeochemical element cycling, horizontal gene transfer and stabilization of biofilm structures. Several protocols based on the precipitation of eDNA e.g. with CTAB and ethanol have already been published. However, using these methods we did not succeed in quantifying very low amounts of eDNA (e.g. <1μg eDNA/g dry wt) in marine sediment even when using DNA carriers like glycogen. Since the recovery of eDNA by precipitation strongly depends on its concentration, these previously published procedures are not adequate for deep biosphere sediment due to the low eDNA content. We have focused on the question whether eDNA could be a source of nitrogen and phosphorus for microbes in the subseafloor biosphere. Therefore we developed a new method for the (semi)-quantitative extraction of eDNA from sediment. The new extraction procedure is based on sequential washing of the sediment to remove simultaneously eDNA and microbial cells without lysing them. After separation of the cells by centrifugation, the eDNA was extracted from the supernatant and purified by adsorption onto a solid phase, followed by removal of the solids and subsequent elution of the pure eDNA. Intracellular DNA (iDNA) was extracted and purified from the cell pellet using a commercial DNA extraction kit. Additional to a very low detection limit and reproducible quantification, this new method allows separation and purification of both extracellular and intracellular DNA to an extent that inhibitors are removed and downstream applications like PCR can be performed. To evaluate the new extraction method two sediments with rather opposing composition were analyzed. Sediment from the South Pacific Gyre, the most oligotrophic oceanic region on earth and organic-rich Baltic Sea sediment (Northern Germany) were processed. Using this new procedure high purity genomic iDNA and eDNA with a molecular size range between 20 bp and 50k bp can be simultaneously recovered even from very oligotrophic sediment with very low cell abundances. The main fraction of recovered eDNA was suitable for downstream applications like PCR and had a molecular size that indicates minimal shearing. Despite about two decades of research many questions about deep subsurface life remain unanswered. The fact that microbes can be found even in deep oligotrophic marine sediment raises the fundamental questions of the types and availability of substrates and their biogeochemical cycling. This is the first study that provides evidence that eDNA is an important potential substrate for microorganisms in the deep biosphere. Also, our results show a link between cell counts and eDNA content, indicating that the eDNA pool in the investigated sediment consist mainly of microbial DNA. Comparative sequence analysis of extracted iDNA and eDNA will provide deeper insights into the origin and turnover of eDNA and the apparent microbial community composition in the deep biosphere.

Scalability Analysis and Use of Compression at the Goddard DAAC and End-to-End MODIS Transfers

NASA Technical Reports Server (NTRS)

Menasce, Daniel A.

1998-01-01

The goal of this task is to analyze the performance of single and multiple FTP transfer between SCF's and the Goddard DAAC. We developed an analytic model to compute the performance of FTP sessions as a function of various key parameters, implemented the model as a program called FTP Analyzer, and carried out validations with real data obtained by running single and multiple FTP transfer between GSFC and the Miami SCF. The input parameters to the model include the mix to FTP sessions (scenario), and for each FTP session, the file size. The network parameters include the round trip time, packet loss rate, the limiting bandwidth of the network connecting the SCF to a DAAC, TCP's basic timeout, TCP's Maximum Segment Size, and TCP's Maximum Receiver's Window Size. The modeling approach used consisted of modeling TCP's overall throughput, computing TCP's delay per FTP transfer, and then solving a queuing network model that includes the FTP clients and servers.

Numerical investigation of heat transfer in annulus laminar flow of multi tubes-in-tube helical coil

NASA Astrophysics Data System (ADS)

Nada, S. A.; Elattar, H. F.; Fouda, A.; Refaey, H. A.

2018-03-01

In the present study, a CFD analysis using ANSYS-FLUENT 14.5 CFD package is used to investigate the characteristics of heat transfer of laminar flow in annulus formed by multi tubes in tube helically coiled heat exchanger. The numerical results are validated by comparison with previous experimental data and fair agreements were existed. The influences of the design and operation parameters such as heat flux, Reynolds numbers and annulus geometry on the heat transfer characteristics are investigated. Different annulus of different numbers of inner tubes, specifically 1, 2, 3, 4 and 5 tubes, are tested. The Results showed that for all the studied annulus, the heat flux has no effect on the Nusselt number and compactness parameter. The annulus formed by using five inner tubes showed the best heat transfer performance and compactness parameter. Correlation of predicting Nusselt number in terms of Reynolds number and number of inner tubes are presented.

An inventory-theory-based interval-parameter two-stage stochastic programming model for water resources management

NASA Astrophysics Data System (ADS)

Suo, M. Q.; Li, Y. P.; Huang, G. H.

2011-09-01

In this study, an inventory-theory-based interval-parameter two-stage stochastic programming (IB-ITSP) model is proposed through integrating inventory theory into an interval-parameter two-stage stochastic optimization framework. This method can not only address system uncertainties with complex presentation but also reflect transferring batch (the transferring quantity at once) and period (the corresponding cycle time) in decision making problems. A case of water allocation problems in water resources management planning is studied to demonstrate the applicability of this method. Under different flow levels, different transferring measures are generated by this method when the promised water cannot be met. Moreover, interval solutions associated with different transferring costs also have been provided. They can be used for generating decision alternatives and thus help water resources managers to identify desired policies. Compared with the ITSP method, the IB-ITSP model can provide a positive measure for solving water shortage problems and afford useful information for decision makers under uncertainty.

Preliminary structural design of a lunar transfer vehicle aerobrake. M.S. Thesis

NASA Technical Reports Server (NTRS)

Bush, Lance B.

1992-01-01

An aerobrake concept for a Lunar transfer vehicle was weight optimized through the use of the Taguchi design method, structural finite element analyses and structural sizing routines. Six design parameters were chosen to represent the aerobrake structural configuration. The design parameters included honeycomb core thickness, diameter to depth ratio, shape, material, number of concentric ring frames, and number of radial frames. Each parameter was assigned three levels. The minimum weight aerobrake configuration resulting from the study was approx. half the weight of the average of all twenty seven experimental configurations. The parameters having the most significant impact on the aerobrake structural weight were identified.

Challenges of model transferability to data-scarce regions (Invited)

NASA Astrophysics Data System (ADS)

Samaniego, L. E.

2013-12-01

Developing the ability to globally predict the movement of water on the land surface at spatial scales from 1 to 5 km constitute one of grand challenges in land surface modelling. Copying with this grand challenge implies that land surface models (LSM) should be able to make reliable predictions across locations and/or scales other than those used for parameter estimation. In addition to that, data scarcity and quality impose further difficulties in attaining reliable predictions of water and energy fluxes at the scales of interest. Current computational limitations impose also seriously limitations to exhaustively investigate the parameter space of LSM over large domains (e.g. greater than half a million square kilometers). Addressing these challenges require holistic approaches that integrate the best techniques available for parameter estimation, field measurements and remotely sensed data at their native resolutions. An attempt to systematically address these issues is the multiscale parameterisation technique (MPR) that links high resolution land surface characteristics with effective model parameters. This technique requires a number of pedo-transfer functions and a much fewer global parameters (i.e. coefficients) to be inferred by calibration in gauged basins. The key advantage of this technique is the quasi-scale independence of the global parameters which enables to estimate global parameters at coarser spatial resolutions and then to transfer them to (ungauged) areas and scales of interest. In this study we show the ability of this technique to reproduce the observed water fluxes and states over a wide range of climate and land surface conditions ranging from humid to semiarid and from sparse to dense forested regions. Results of transferability of global model parameters in space (from humid to semi-arid basins) and across scales (from coarser to finer) clearly indicate the robustness of this technique. Simulations with coarse data sets (e.g. EOBS forcing 25x25 km2, FAO soil map 1:5000000) using parameters obtained with high resolution information (REGNIE forcing 1x1 km2, BUEK soil map 1:1000000) in different climatic regions indicate the potential of MPR for prediction in data-scarce regions. In this presentation, we will also discuss how the transferability of global model parameters across scales and locations helps to identify deficiencies in model structure and regionalization functions.

Probing Metabolic Activity of Deep Subseafloor Life with NanoSIMS

NASA Astrophysics Data System (ADS)

Morono, Y.; Terada, T.; Itoh, M.; Inagaki, F.

2014-12-01

There are very few natural environments where life is absent in the Earth's surface biosphere. However, uninhabitable region is expected to be exist in the deep subsurface biosphere, of which extent and constraining factor(s) have still remained largly unknown. Scientific ocean drilling have revealed that microbial communities in sediments are generally phylogenetically distinct from known spieces isolated from the Earth's surface biosphere, and hence metabolic functions of the deep subseafloor life remain unknown. In addition, activity of subseafloor microbial cells are thought to be extraordinally slow, as indicated by limited supply of neutrient and energy substrates. To understand the limits of the Earth's subseafloor biosphere and metabolic functions of microbial populations, detection and quantification of the deeply buried microbial cells in geological habitats are fundamentary important. Using newly developed cell separation techniques as well as an discriminative cell detection system, the current quantification limit of sedimentary microbial cells approaches to 102 cells/cm3. These techniques allow not only to assess very small microbial population close to the subsurface biotic fringe, but also to separate and sort the target cells using flow cytometric cell sorter. Once the deep subseafloor microbial cells are detached from mineral grains and sorted, it opens new windows to subsequent molecular ecological and element/isotopic analyses. With a combined use of nano-scale secondary ion masspectrometry (NanoSIMS) and stable isotope-probing techniques, it is possible to detect and measure activity of substrate incorporation into biomass, even for extremely slow metabolic processes such as uncharacteriszed deep subseafloor life. For example, it was evidenced by NanoSIMS that at least over 80% of microbial cells at ~200 meters-deep, 460,000-year-old sedimentary habitat are indeed live, which substrate incooporation was found to be low (10-15 gC/cell/day) even under the lab incubation condition. Also microbial activity in ultraoligotrophic biosphere samples such as the South Pacific Gyre (i.e., IODP Expeditions 329) will be shown. Our results demonstrates metabolic potential of microbes that have been survived for geological timescale in extremely starved condition.

Nitrogen Fertilization of Corn: Plant Biochemistry Effects and Carbon Cycle Implications

NASA Astrophysics Data System (ADS)

Gallagher, M. E.; Hockaday, W. C.; Masiello, C. A.; McSwiney, C. P.; Robertson, G. P.; Baldock, J. A.

2008-05-01

Atmospheric carbon dioxide (CO2) concentrations are rising due to anthropogenic CO2 emissions (Alley et al. 2007; Prentice et al. 2001). About half of the anthropogenic CO2 emitted during the 1990s was absorbed by the terrestrial biosphere and ocean (Prentice et al. 2001). It is possible to estimate the size of terrestrial and oceanic carbon sinks individually using atmospheric CO2 and O2 measurements (Keeling et al. 1996). To best estimate the sizes of these carbon sinks, we need to accurately know the oxidative ratio (OR) of the terrestrial biosphere (Randerson et al. 2006). OR is the ratio of the moles of O2 released per moles of CO2 consumed in gas fluxes between the terrestrial biosphere and atmosphere. Though it is likely that the net OR of the biosphere varies with ecosystem type and nutrient status, OR is assumed constant in carbon sink apportionment calculations (e.g. Prentice et al. 2001). Small shifts in OR can lead to large variations in the calculated sizes of the terrestrial biosphere and ocean carbon sinks (Randerson et al. 2006). OR likely shifts with changes in climate, nutrient status, and land use. These shifts are due, in part, to shifts in plant biochemistry. We are measuring ecosystem OR in corn agricultural ecosystems under a range of nitrogen fertilization treatments at the Kellogg Biological Station-Long Term Ecological Research Site (KBS-LTER) in Michigan. We measure OR indirectly, through its relationship with organic carbon oxidation state (Cox) (Masiello et al. in press 2008). Cox can be measured through elemental analysis and, with basic knowledge of plant nitrogen use patterns, Cox values can be converted to OR values. Cox can also be measured through 13C nuclear magnetic resonance spectroscopy (NMR), which can be combined with a molecular mixing model to determine Cox, OR, and plant biochemical composition (i.e. percentage carbohydrates, lignin, lipids, and proteins) (Baldock et al. 2004). Here we present data showing the effects of varying corn ecosystem nitrogen fertilization rates (from 0 to 292 kg N/ha) on ecosystem OR and plant biochemistry.