Sample records for microclimate
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ERIC Educational Resources Information Center
Fontaine, Joseph J.; Stier, Samuel C.; Maggio, Melissa L.; Decker, Karie L.
2007-01-01
Students can gain an appreciation for the structure and function of local environments by studying the potential impacts of small changes in local microclimate on plant distribution. The concept of microclimate is easy for students to comprehend, simple to measure, exists in all schoolyards, and has important and tangible ecological implications.…
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Lenzholzer, Sanda
2010-03-01
Acceptance of public spaces is often guided by perceptual schemata. Such schemata also seem to play a role in thermal comfort and microclimate experience. For climate-responsive design with a focus on thermal comfort it is important to acquire knowledge about these schemata. For this purpose, perceived and "real" microclimate situations were compared for three Dutch urban squares. People were asked about their long-term microclimate perceptions, which resulted in "cognitive microclimate maps". These were compared with mapped microclimate data from measurements representing the common microclimate when people stay outdoors. The comparison revealed some unexpected low matches; people clearly overestimated the influence of the wind. Therefore, a second assumption was developed: that it is the more salient wind situations that become engrained in people's memory. A comparison using measurement data from windy days shows better matches. This suggests that these more salient situations play a role in the microclimate schemata that people develop about urban places. The consequences from this study for urban design are twofold. Firstly, urban design should address not only the "real" problems, but, more prominently, the "perceived" problems. Secondly, microclimate simulations addressing thermal comfort issues in urban spaces should focus on these perceived, salient situations.
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Tree structure and cavity microclimate: implications for bats and birds.
Clement, Matthew J; Castleberry, Steven B
2013-05-01
It is widely assumed that tree cavity structure and microclimate affect cavity selection and use in cavity-dwelling bats and birds. Despite the interest in tree structure and microclimate, the relationship between the two has rarely been quantified. Currently available data often comes from artificial structures that may not accurately represent conditions in natural cavities. We collected data on tree cavity structure and microclimate from 45 trees in five cypress-gum swamps in the Coastal Plain of Georgia in the United States in 2008. We used hierarchical linear models to predict cavity microclimate from tree structure and ambient temperature and humidity, and used Aikaike's information criterion to select the most parsimonious models. We found large differences in microclimate among trees, but tree structure variables explained <28% of the variation, while ambient conditions explained >80% of variation common to all trees. We argue that the determinants of microclimate are complex and multidimensional, and therefore cavity microclimate cannot be deduced easily from simple tree structures. Furthermore, we found that daily fluctuations in ambient conditions strongly affect microclimate, indicating that greater weather fluctuations will cause greater differences among tree cavities.
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Grisham, Blake A.; Godar, Alixandra J.; Boal, Clint W.; Haukos, David A.
2016-01-01
The range of Lesser Prairie-Chickens (Tympanuchus pallidicinctus) spans 4 unique ecoregions along 2 distinct environmental gradients. The Sand Shinnery Oak Prairie ecoregion of the Southern High Plains of New Mexico and Texas is environmentally isolated, warmer, and more arid than the Short-Grass, Sand Sagebrush, and Mixed-Grass Prairie ecoregions in Colorado, Kansas, Oklahoma, and the northeast panhandle of Texas. Weather is known to influence Lesser Prairie-Chicken nest survival in the Sand Shinnery Oak Prairie ecoregion; regional variation may also influence nest microclimate and, ultimately, survival during incubation. To address this question, we placed data loggers adjacent to nests during incubation to quantify temperature and humidity distribution functions in 3 ecoregions. We developed a suite of a priori nest survival models that incorporated derived microclimate parameters and visual obstruction as covariates in Program MARK. We monitored 49 nests in Mixed-Grass, 22 nests in Sand Shinnery Oak, and 30 nests in Short-Grass ecoregions from 2010 to 2014. Our findings indicated that (1) the Sand Shinnery Oak Prairie ecoregion was hotter and drier during incubation than the Mixed- and Short-Grass ecoregions; (2) nest microclimate varied among years within ecoregions; (3) visual obstruction was positively associated with nest survival; but (4) daily nest survival probability decreased by 10% every half-hour when temperature was greater than 34°C and vapor pressure deficit was less than −23 mmHg during the day (about 0600–2100 hours). Our major finding confirmed microclimate thresholds for nest survival under natural conditions across the species' distribution, although Lesser Prairie-Chickens are more likely to experience microclimate conditions that result in nest failures in the Sand Shinnery Oak Prairie ecoregion. The species would benefit from identification of thermal landscapes and management actions that promote cooler, more humid nest microclimates.
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[Occupational microclimate. Results and prospects of research].
Afanas'eva, R F; Bessonova, N A; Burmistrova, O V; Burmistrov, V M; Losik, T K
2013-01-01
The article covers results of studies conducted over last 15 years and aimed to elaboration of requirements to integral parameters of microclimate at workplace, its evaluation and regulation, prophylactic measures against body overcooling and overheating. The authors present methods to evaluate combined effects of physical factors (noise, vibration, microclimate) and to assess microclimate with consideration of factors determining body thermal load (energy expenditure, duration of stay at workplace, heat insulation of clothes and thermo-physical parameters of its materials). Mathematic models of forecasting cold and heat stress are presented, as well as requirements to heat insulation for individual protective means against cold and methods to calculate it. Regimens of work in heating and cooling conditions are specified. The authors set directions for further studies to define regulation requirements to microclimate on basis of studied patterns of body heat state formation, its evaluation criteria, epidemiologic studies results, specified prophylactic measures against overheating and overcooling with consideration of adaptation, sex, thermo-physical characteristics of individual protective means (special clothes, footwear, gauntlets, headwear).
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Measuring the human body's microclimate using a thermal manikin.
Voelker, C; Maempel, S; Kornadt, O
2014-12-01
The human body is surrounded by a microclimate, which results from its convective release of heat. In this study, the air temperature and flow velocity of this microclimate were measured in a climate chamber at various room temperatures, using a thermal manikin simulating the heat release of the human being. Different techniques (Particle Streak Tracking, thermography, anemometry, and thermistors) were used for measurement and visualization. The manikin surface temperature was adjusted to the particular indoor climate based on simulations with a thermoregulation model (UCBerkeley Thermal Comfort Model). We found that generally, the microclimate is thinner at the lower part of the torso, but expands going up. At the head, there is a relatively thick thermal layer, which results in an ascending plume above the head. However, the microclimate shape strongly depends not only on the body segment, but also on boundary conditions: The higher the temperature difference between the surface temperature of the manikin and the air temperature, the faster the airflow in the microclimate. Finally, convective heat transfer coefficients strongly increase with falling room temperature, while radiative heat transfer coefficients decrease. The type of body segment strongly influences the convective heat transfer coefficient, while only minimally influencing the radiative heat transfer coefficient. The findings of this study generate a better understanding of the human body’s microclimate, which is important in fields such as thermal comfort, HVAC, or indoor air quality. Additionally, the measurements can be used by CFD users for the validation of their simulations. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
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Microclimate and nest-site selection in Micronesian Kingfishers
Kesler, Dylan C.; Haig, Susan M.
2005-01-01
We studied the relationship between microclimate and nest-site selection in the Pohnpei Micronesian Kingfisher (Todiramphus cinnamominus reichenbachii) which excavates nest cavities from the mudlike nest structures of arboreal termites (Nasutitermes sp.) or termitaria. Mean daily high temperatures at termitaria were cooler and daily low temperatures were warmer than at random sites in the forest. Results also indicate that termitaria provided insulation from temperature extremes, and that temperatures inside termitaria were within the thermoneutral zone of Micronesian Kingfishers more often than those outside. No differences were identified in temperatures at sites where nest termitaria and nonnest termitaria occurred or among the insulation properties of used and unused termitaria. These results suggest that although termitaria provide insulation from thermal extremes and a metabolically less stressful microclimate, king-fishers did not select from among available termitaria based on their thermal properties. Our findings are relevant to conservation efforts for the critically endangered Guam Micronesian Kingfisher (T. c. cinnamominus) which is extinct in the wild and exists only as a captive population. Captive breeding facilities should provide aviaries with daily ambient temperatures ranging from 22.06 A?C to 28.05 A?C to reduce microclimate-associated metabolic stress and to replicate microclimates used by wild Micronesian Kingfishers.
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Mangrove microclimates alter seedling dynamics at the range edge.
Devaney, John L; Lehmann, Michael; Feller, Ilka C; Parker, John D
2017-10-01
Recent climate warming has led to asynchronous species migrations, with major consequences for ecosystems worldwide. In woody communities, localized microclimates have the potential to create feedback mechanisms that can alter the rate of species range shifts attributed to macroclimate drivers alone. Mangrove encroachment into saltmarsh in many areas is driven by a reduction in freeze events, and this encroachment can further modify local climate, but the subsequent impacts on mangrove seedling dynamics are unknown. We monitored microclimate conditions beneath mangrove canopies and adjacent open saltmarsh at a freeze-sensitive mangrove-saltmarsh ecotone and assessed survival of experimentally transplanted mangrove seedlings. Mangrove canopies buffered night time cooling during the winter, leading to interspecific differences in freeze damage on mangrove seedlings. However, mangrove canopies also altered biotic interactions. Herbivore damage was higher under canopies, leading to greater mangrove seedling mortality beneath canopies relative to saltmarsh. While warming-induced expansion of mangroves can lead to positive microclimate feedbacks, simultaneous fluctuations in biotic drivers can also alter seedling dynamics. Thus, climate change can drive divergent feedback mechanisms through both abiotic and biotic channels, highlighting the importance of vegetation-microclimate interactions as important moderators of climate driven range shifts. © 2017 by the Ecological Society of America.
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Comparison of Microclimate Simulated weather data to ASHRAE Clear Sky Model and Measured Data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhandari, Mahabir S.
In anticipation of emerging global urbanization and its impact on microclimate, a need exists to better understand and quantify microclimate effects on building energy use. Satisfaction of this need will require coordinated research of microclimate impacts on and from “human systems.” The Urban Microclimate and Energy Tool (Urban-MET) project seeks to address this need by quantifying and analyzing the relationships among climatic conditions, urban morphology, land cover, and energy use; and using these relationships to inform energy-efficient urban development and planning. Initial research will focus on analysis of measured and modeled energy efficiency of various building types in selected urbanmore » areas and temporal variations in energy use for different urban morphologies under different microclimatic conditions. In this report, we analyze the differences between microclimate weather data sets for the Oak Ridge National Laboratory campus produced by ENVI-met and Weather Research Forecast (WRF) models, the ASHRAE clear sky which defines the maximum amounts of solar radiation that can be expected, and measured data from a weather station on campus. Errors with climate variables and their impact on building energy consumption will be shown for the microclimate simulations to help prioritize future improvement for use in microclimate simulation impacts to energy use of buildings.« less
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Geostatistical modeling of riparian forest microclimate and its implications for sampling
Eskelson, B.N.I.; Anderson, P.D.; Hagar, J.C.; Temesgen, H.
2011-01-01
Predictive models of microclimate under various site conditions in forested headwater stream - riparian areas are poorly developed, and sampling designs for characterizing underlying riparian microclimate gradients are sparse. We used riparian microclimate data collected at eight headwater streams in the Oregon Coast Range to compare ordinary kriging (OK), universal kriging (UK), and kriging with external drift (KED) for point prediction of mean maximum air temperature (Tair). Several topographic and forest structure characteristics were considered as site-specific parameters. Height above stream and distance to stream were the most important covariates in the KED models, which outperformed OK and UK in terms of root mean square error. Sample patterns were optimized based on the kriging variance and the weighted means of shortest distance criterion using the simulated annealing algorithm. The optimized sample patterns outperformed systematic sample patterns in terms of mean kriging variance mainly for small sample sizes. These findings suggest methods for increasing efficiency of microclimate monitoring in riparian areas.
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Microclimate landscape design at southern integrated terminal Bandar Tasik Selatan, Kuala Lumpur
NASA Astrophysics Data System (ADS)
Phin, L. H.; Krisantia, I.
2018-01-01
Bandar Tasik Selatan is the integrated transport terminal has high energy consuming, high carbon emission and poor linkage. However, microclimate can be reduced through landscape design. This paper is a study to achieve energy efficiency and improve microclimate in the urban area. The research area is at Southern integrated terminal Bandar Tasik Selatan Kuala Lumpur Malaysia. It is carried out through a case study and microclimate analyzed using System Modeling method. System modelling using in this research is system energy budget of the microclimate at a site is a balance between the radiant energy supplied and the energy removed by all consumers. The finding indicated the microclimatic components that can be modified through landscape design are solar radiation, wind and precipitation can create thermal comfort, energy efficiency and others benefits.Through this research, provide more green space to achieve energy efficiency and improve microclimate of the site, introducing vertical landscape and proper planting selection to improve air quality, introducing green energy as part of the source of power supply and to promote integration of terminal building and rail systems by unify them using softscape
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Use of a coverlet system for the management of skin microclimate.
Collier, Mark; Potts, Carol; Shaw, Elaine
2014-08-12
Pressure and shear are the two key extrinsic factors that cause pressure ulcer damage. However, if the resilience of the skin and soft tissue deteriorates, the individual's susceptibility to such pressure damage will increase. The risk is greater if the microclimate at the interface between the skin and the support surface is impaired. This will occur when the skin temperature is elevated and there is excess moisture on the skin surface. Microclimate management therefore plays an important role in pressure ulcer prevention. This article describes how use of a new coverlet system (Skin IQ Microclimate Manager, ArjoHuntleigh) can avoid the accumulation of heat and moisture at the patient/support-surface interface.
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Mayor, T S; Couto, S; Psikuta, A; Rossi, R M
2015-12-01
The ability of clothing to provide protection against external environments is critical for wearer's safety and thermal comfort. It is a function of several factors, such as external environmental conditions, clothing properties and activity level. These factors determine the characteristics of the different microclimates existing inside the clothing which, ultimately, have a key role in the transport processes occurring across clothing. As an effort to understand the effect of transport phenomena in clothing microclimates on the overall heat transport across clothing structures, a numerical approach was used to study the buoyancy-driven heat transfer across horizontal air layers trapped inside air impermeable clothing. The study included both the internal flow occurring inside the microclimate and the external flow occurring outside the clothing layer, in order to analyze the interdependency of these flows in the way heat is transported to/from the body. Two-dimensional simulations were conducted considering different values of microclimate thickness (8, 25 and 52 mm), external air temperature (10, 20 and 30 °C), external air velocity (0.5, 1 and 3 m s(-1)) and emissivity of the clothing inner surface (0.05 and 0.95), which implied Rayleigh numbers in the microclimate spanning 4 orders of magnitude (9 × 10(2)-3 × 10(5)). The convective heat transfer coefficients obtained along the clothing were found to strongly depend on the transport phenomena in the microclimate, in particular when natural convection is the most important transport mechanism. In such scenario, convective coefficients were found to vary in wavy-like manner, depending on the position of the flow vortices in the microclimate. These observations clearly differ from data in the literature for the case of air flow over flat-heated surfaces with constant temperature (which shows monotonic variations of the convective heat transfer coefficients, along the length of the surface). The flow
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Physiological reaction to work in cold microclimate.
Bortkiewicz, Alicja; Gadzicka, Elzbieta; Szymczak, Wiesław; Szyjkowska, Agata; Koszada-Włodarczyk, Wiesława; Makowiec-Dabrowska, Teresa
2006-01-01
In Poland, occupational exposure to cold microclimate is quite common (5.1 workers/1000 occupationally active people). Reports on health effects of this exposure are rather scarce. The aim of the study was to evaluate the physiological reaction in workers occupationally exposed to cold microclimate. Examinations were performed in a group of 102 workers (41 women and 61 men) employed at cold storage units. The mean age in the group was 39.1 +/- 9.9 years and the duration of employment under conditions of cold environment was over 12 years. The study population was divided into four groups, according to microclimate conditions (group I, ambient temperature -26 degrees C; group II, 10-14 degrees C; group III, 18-20 degrees C, control group; and group IV, 0-10 degress C). The workers underwent the following procedures: general medical examinations, cold pressor test, ambulatory blood pressure monitoring, and heart rate variability (HRV) analysis (time- and frequency-domain parameters). The results were adjusted for confounding factors (age, smoking and drinking habits). The analysis of HRV parameters did not reveal any significant differences between the study groups. However, systolic and diastolic blood pressure (BP) in the daytime and at night was significantly higher in group IV compared to group II. Mean heart rate (HR) in the daytime and at night and the BP and HR day/night ratio did not differ between the groups. The analysis of BP by gender revealed that in women, systolic BP during the day and at night was significantly higher in group IV than in group II. In the group of workers with hypertension (18 men and 5 women), men reacted to the cold pressor test either by increased or decreased BP while all the women reacted by the increased BP. Our findings indicated that in workers exposed to cold microclimate, the physiological reaction was dependent on gender and ambient temperature. Women seemed to be more sensitive to cold stress than men. However, this finding
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NASA Astrophysics Data System (ADS)
Buhmirov, V. V.; Prorokova, M. V.
2015-01-01
The method of determining a microclimate comfort level have been developed, taking into account the main parameters influencing the microclimate in residential, public and administration buildings, their mutual influence on the comfort level, and air quality.
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Predicting the size and elevation of future mountain forests: Scaling macroclimate to microclimate
NASA Astrophysics Data System (ADS)
Cory, S. T.; Smith, W. K.
2017-12-01
Global climate change is predicted to alter continental scale macroclimate and regional mesoclimate. Yet, it is at the microclimate scale that organisms interact with their physiochemical environments. Thus, to predict future changes in the biota such as biodiversity and distribution patterns, a quantitative coupling between macro-, meso-, and microclimatic parameters must be developed. We are evaluating the impact of climate change on the size and elevational distribution of conifer mountain forests by determining the microclimate necessary for new seedling survival at the elevational boundaries of the forest. This initial life stage, only a few centimeters away from the soil surface, appears to be the bottleneck to treeline migration and the expansion or contraction of a conifer mountain forest. For example, survival at the alpine treeline is extremely rare and appears to be limited to facilitated microsites with low sky exposure. Yet, abundant mesoclimate data from standard weather stations have rarely been scaled to the microclimate level. Our research is focusing on an empirical downscaling approach linking microclimate measurements at favorable seedling microsites to the meso- and macro-climate levels. Specifically, mesoclimate values of air temperature, relative humidity, incident sunlight, and wind speed from NOAA NCEI weather stations can be extrapolated to the microsite level that is physiologically relevant for seedling survival. Data will be presented showing a strong correlation between incident sunlight measured at 2-m and seedling microclimate, despite large differences from seedling/microsite temperatures. Our downscaling approach will ultimately enable predictions of microclimate from the much more abundant mesoclimate data available from a variety of sources. Thus, scaling from macro- to meso- to microclimate will be possible, enabling predictions of climate change models to be translated to the microsite level. This linkage between measurement
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Afanas'eva, R F
2008-01-01
The article deals with basic points concerning influence of microclimate on humans and tasks of its regulation in contemporary conditions. The authors described universality of microclimate from viewpoint of producing functional state and health state of human, so microclimate should be assessed consistently and systematically through all aspects of its influence, with complex approach to evaluation (clothing, physical activity, etc.).
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MTCLIM: a mountain microclimate simulation model
Roger D. Hungerford; Ramakrishna R. Nemani; Steven W. Running; Joseph C. Coughlan
1989-01-01
A model for calculating daily microclimate conditions in mountainous terrain is presented. Daily air temperature, shortwave radiation, relative humidity, and precipitation are extrapolated form data measured at National Weather Service stations. The model equations are given and the paper describes how to execute the model. Model outputs are compared with observed data...
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The Microclimate of a Tropical Evergreen Forest.
1980-08-01
of Human Bioclimate - A Review. World Meteorological Organization Bulletin, Geneva, 56 pp. REFERENCES (con’t) Lee, R., 1978. Forest Micrometeorology...Geophysics, and Bioclimatology , Ser. B 24, 243-251. Pinker, R. (1980): The Microclimate of a dry tropical forest. (Accepted for publication in
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Integration of remote sensing based surface information into a three-dimensional microclimate model
NASA Astrophysics Data System (ADS)
Heldens, Wieke; Heiden, Uta; Esch, Thomas; Mueller, Andreas; Dech, Stefan
2017-03-01
Climate change urges cities to consider the urban climate as part of sustainable planning. Urban microclimate models can provide knowledge on the climate at building block level. However, very detailed information on the area of interest is required. Most microclimate studies therefore make use of assumptions and generalizations to describe the model area. Remote sensing data with area wide coverage provides a means to derive many parameters at the detailed spatial and thematic scale required by urban climate models. This study shows how microclimate simulations for a series of real world urban areas can be supported by using remote sensing data. In an automated process, surface materials, albedo, LAI/LAD and object height have been derived and integrated into the urban microclimate model ENVI-met. Multiple microclimate simulations have been carried out both with the dynamic remote sensing based input data as well as with manual and static input data to analyze the impact of the RS-based surface information and the suitability of the applied data and techniques. A valuable support of the integration of the remote sensing based input data for ENVI-met is the use of an automated processing chain. This saves tedious manual editing and allows for fast and area wide generation of simulation areas. The analysis of the different modes shows the importance of high quality height data, detailed surface material information and albedo.
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Landscape-Scale Soil Carbon Inventories by Microclimate Decomposition
NASA Astrophysics Data System (ADS)
Beaudette, D. E.; O'Geen, A. T.
2008-12-01
Estimation of carbon stocks in rangeland and foothill ecosystems is poised to become an important service once legislation regulating greenhouse gas emissions is passed. Trading of carbon credits and greenhouse gas emission/sequestration budgets for vegetated areas is largely dependent on an accurate and scale- dependent inventory of existing conditions. Soil survey presents one possible resource for surface carbon stocks, however these data are usually not mapped at the landscape-scale. Soil-landscape modeling techniques have been successfully used in several instances to predict the spatial variation in soil carbon. Most of these studies have used site exposure (aspect angle) as a categorical proxy for terrain-induced microclimate. Our objective was to model parameters related to soil microclimate (soil temperature and moisture) for the production of detailed maps of soil carbon and organic matter quality (i.e. C:N ratio). We used a solar radiation model and long-term monitoring of soil moisture and temperature to generate several models of soil microclimate. Parameterization of the ESRA (European Solar Radiation Atlas) solar radiation model (clear-sky version) was accomplished with daily estimates of the Linke turbidity factor, using local pyranometer measurements (11 year record). Our estimated daily radiance values correlated well with local weather station data (R2 = 0.965, p < 0.001). This model is included in the popular, open source GRASS GIS. A preliminary study based on 35 sites, spanning two contrasting landform types (and lithology), revealed a statistically significant relationship between annual radiation load and carbon (R2 = 0.75, p < 0.001). A highly significant relationship between C:N ratio and annual radiation load was identified as well (R2 = 0.99, p < 0.001). Solar radiation models are simple to use, and have the potential to refine previous soil-landscape modeling efforts that relied on aspect class or angle. Models linking surface processes
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2012-12-01
TROPIC CONDITIONS: EFFECTS OF THREE MICROCLIMATE COOLING CONFIGURATIONS Bruce S. Cadarette Catherine O’Brien Thermal and Mountain...Cooling HR – Heart Rate INT – Intermittent Cooling LO – Low Cooling MCCS – Microclimate Cooling System NC – No Cooling NSRDEC – Natick...develop lightweight microclimate cooling systems (MCCS) for use by dismounted Soldiers by evaluating the cooling potentials of two prototype MCCS
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[Work schedule of electric welders in heating microclimate].
Sorokin, G A; Frolova, N M
2010-01-01
The authors present results of specified hygienically justified timing regulations for setting the variants of work and rest modes within electric welders shift, who work in various postures with variable visual strain while welding in heating microclimate.
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Microclimate in Forest Ecosystem and Landscape Ecology
Jiquan Chen; Sari C. Saunders; Thomas R. Crow; Robert J. Naiman; Kimberley D. Brosofske; Glenn D. Mroz; Brain L. Brookshire; Jerry F. Franklin
1999-01-01
Microclimate is the suite of climatic conditions measured in localized areas near the earth's surface (Geiger 1965). These environmental variables, which include temperature, light, windspeed, and moisture, have been critical throughout human history, providing meaningful indicators for habitat selection and other activities. For example, for 2600 years the...
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Unger, K A; Watterson, J H
2016-10-01
The effects of decomposition microclimate on the distribution of dextromethorphan (DXM) and dextrorphan (DXT) in skeletonized remains of rats acutely exposed to DXM were examined. Animals (n = 10) received DXM (75 mg/kg, i.p.), were euthanized 30 min post-dose and immediately allowed to decompose at either Site A (shaded forest microenvironment on a grass-covered soil substrate) or Site B (rocky substrate exposed to direct sunlight, 600 m from Site A). Ambient temperature and relative humidity were automatically recorded 3 cm above rats at each site. Skeletal elements (vertebral columns, ribs, pelvic girdles, femora, tibiae, humeri and scapulae) were harvested, and analyzed using microwave assisted extraction, microplate solid phase extraction, and GC/MS. Drug levels, expressed as mass-normalized response ratios, and the ratios of DXT and DXM levels were compared across bones and between microclimate sites. No significant differences in DXT levels or metabolite/parent ratios were observed between sites or across bones. Only femoral DXM levels differed significantly between microclimate sites. For pooled data, microclimate was not observed to significantly affect analyte levels, nor the ratio of levels of DXT and DXM. These data suggest that microclimate conditions do not influence DXM and metabolite distribution in skeletal remains. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Cornthwaite, H M; Watterson, J H
2014-10-01
The influence of body position and microclimate on ketamine (KET) and metabolite distribution in decomposed bone tissue was examined. Rats received 75 mg/kg (i.p.) KET (n = 30) or remained drug-free (controls, n = 4). Following euthanasia, rats were divided into two groups and placed outdoors to decompose in one of the three positions: supine (SUP), prone (PRO) or upright (UPR). One group decomposed in a shaded, wooded microclimate (Site 1) while the other decomposed in an exposed sunlit microclimate with gravel substrate (Site 2), roughly 500 m from Site 1. Following decomposition, bones (lumbar vertebrae, thoracic vertebra, cervical vertebrae, rib, pelvis, femora, tibiae, humeri and scapulae) were collected and sorted for analysis. Clean, ground bones underwent microwave-assisted extraction using acetone : hexane mixture (1 : 1, v/v), followed by solid-phase extraction and analysis using GC-MS. Drug levels, expressed as mass normalized response ratios, were compared across all bone types between body position and microclimates. Bone type was a main effect (P < 0.05) for drug level and drug/metabolite level ratio for all body positions and microclimates examined. Microclimate and body position significantly influenced observed drug levels: higher levels were observed in carcasses decomposing in direct sunlight, where reduced entomological activity led to slowed decomposition. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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[To the issue on the optimization and regulation of microclimate in the subway trains and stations].
Leksin, A G; Beresneva, T G; Kaptsov, V A; Korotich, L P; Evlampieva, M N; Timoshenkova, E V
2014-01-01
There is presented an overview of currently existing regulatory framework governing the parameters of the microclimate in the salons of subway passenger cars and stations. Analysis of the normative documents indicated that they contain very incomplete, contradictory, often unfounded information about the parameters of microclimate parameters in salons of subway rolling stock. Also, there are no clear cut hygienically-sound requirements for the work of imposed on the rolling stock subway systems provide microclimate, including new systems for air conditioning and disinfection.
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Soil microclimate monitoring in forested and meadow sites
NASA Astrophysics Data System (ADS)
Freyerova, Katerina; Safanda, Jan
2016-04-01
It is well known fact that forest microclimate differs from open area microclimate (Geiger 1965). Less attention is paid to soil temperatures and their long-term monitoring. To evaluate and compare these two environments from the soil microclimate point of view, Institute of Geophysics in Prague monitors soil and air temperatures in Bedřichov in the Jizerské Hory Mountains (Czech Republic). The soil temperatures are measured in three depths (20, 50 and 100 cm) in forest (700 m a. s. l.) and meadow (750 m a. s. l.). Air temperatures are measured at 2m height both in forest and meadow. Nowadays, we have more than three years long time series. The most of studies and experiments described in literature are short-term ones (in order of days or weeks). However, from short-term experiments the seasonal behaviour and trends can be hardly identified and conclusions on soil temperature reaction to climatic extremes such as heat waves, drought or freeze cannot be done with confidence. These drawbacks of the short-term experiments are discussed in literature (eg. Morecroft et al. 1998; Renaud et al. 2011). At the same, with progression of the global warming, the expected increasing frequency of climatic extremes will affect the future form of forest vegetation (Von Arx et al. 2012). The soil and air temperature series, both from the forest and meadow sites, are evaluated and interpreted with respect to long term temperature characteristics and seasonal trends. The emphasis is given on the soil temperature responses to extreme climatic situations. We examine variability between the localities and depths and spatial and temporal changes in this variability. This long-term monitoring allows us to better understand and examine the behaviour of the soil temperature in extreme weather situations. Therefore, we hope to contribute to better prediction of future reactions of this specific environments to the climate change. Literature Geiger, R., 1965. The climate near the ground
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2012-12-01
USARIEM TECHNICAL REPORT PHYSIOLOGICAL RESPONSES TO MICROCLIMATE COOLING USED BY THE AIR SOLDIER DRESSED AT MOPP 4 IN AN...2012 2. REPORT TYPE 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Physiological Responses to Microclimate Cooling Used By the Air Soldier 5b. GRANT... Microclimate Cooling System MCG HI – Air Warrior Microclimate Cooling Garment Used in High Cooling Configuration MCG LO - Air Warrior Microclimate
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Assessment of turkey vehicle container microclimate on transit during summer season conditions
NASA Astrophysics Data System (ADS)
Carvalho, Rafael H.; Honorato, Danielle C. B.; Guarnieri, Paulo D.; Soares, Adriana L.; Pedrão, Mayka R.; Oba, Alexandre; Paião, Fernanda G.; Ida, Elza I.; Shimokomaki, Massami
2018-06-01
This study evaluated the formed microclimate commercial truck transport practices effects on the turkeys' welfare by measuring Dead on Arrival (DOA) index and pale, soft, and exudative (PSE-like) meat occurrence. The experimental design was entirely randomized in a 6 × 2 factorial arrangements (two truck container compartments × six water shower groups) with birds positioned at superior front (SF), inferior front (IF), superior middle (SM), inferior middle (IM), superior rear (SR), and inferior rear (IR) and two bath treatments: with water shower (WiS) and without water shower (WoS) with eight replications for each treatment. The animals were transported for 95 min' journey from the farm to the slaughterhouse under hot-humidity conditions. The results shown herein indicated the formation of a thermal core at the inferior middle and rear truck container regions, because the heat produced by the birds and the influence of developed microclimate consisting of temperature, relative humidity, and air ventilation. The IM and IR container compartments under the WoS treatment presented the highest ( P < 0.01) numbers of PSE-like meat incidence and DOA index values compared with those located at the front under WiS treatment as the consequence of the altered to birds unbearable conditions within the container microclimate in transit. The formed microclimate during the commercial transport practices under hot-humidity conditions affected the bird's welfare consequently turkey meat qualities.
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Assessment of turkey vehicle container microclimate on transit during summer season conditions
NASA Astrophysics Data System (ADS)
Carvalho, Rafael H.; Honorato, Danielle C. B.; Guarnieri, Paulo D.; Soares, Adriana L.; Pedrão, Mayka R.; Oba, Alexandre; Paião, Fernanda G.; Ida, Elza I.; Shimokomaki, Massami
2018-01-01
This study evaluated the formed microclimate commercial truck transport practices effects on the turkeys' welfare by measuring Dead on Arrival (DOA) index and pale, soft, and exudative (PSE-like) meat occurrence. The experimental design was entirely randomized in a 6 × 2 factorial arrangements (two truck container compartments × six water shower groups) with birds positioned at superior front (SF), inferior front (IF), superior middle (SM), inferior middle (IM), superior rear (SR), and inferior rear (IR) and two bath treatments: with water shower (WiS) and without water shower (WoS) with eight replications for each treatment. The animals were transported for 95 min' journey from the farm to the slaughterhouse under hot-humidity conditions. The results shown herein indicated the formation of a thermal core at the inferior middle and rear truck container regions, because the heat produced by the birds and the influence of developed microclimate consisting of temperature, relative humidity, and air ventilation. The IM and IR container compartments under the WoS treatment presented the highest (P < 0.01) numbers of PSE-like meat incidence and DOA index values compared with those located at the front under WiS treatment as the consequence of the altered to birds unbearable conditions within the container microclimate in transit. The formed microclimate during the commercial transport practices under hot-humidity conditions affected the bird's welfare consequently turkey meat qualities.
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Hydrothermal assessment of temporal variability in seedbed microclimate
USDA-ARS?s Scientific Manuscript database
The microclimatic requirements for successful establishment of rangeland species are much more restrictive than those required for maintenance of mature plant communities. We used a 44-year weather record to parameterize a seedbed-microclimate model for estimation of hourly temperature and moisture...
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Insect Infestations Linked to Shifts in Microclimate: Important Climate Change Implications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Classen, Aimee T; Hart, Stephen C; Whitham, Thomas G
Changes in vegetation due to drought-influenced herbivory may influence microclimate in ecosystems. In combination with studies of insect resistant and susceptible trees, we used long-term herbivore removal experiments with two herbivores of pinon (Pinus edulis Endelm.) to test the general hypothesis that herbivore alteration of plant architecture affects soil microclimate, a major driver of ecosystem-level processes. The pinon needle scale (Matsucoccus acalyptus, Herbert) attacks needles of juvenile trees causing them to develop an open crown. In contrast, the stem-boring moth (Dioryctria albovittella Hulst.) kills the terminal shoots of mature trees, causing the crown to develop a dense form. Our studiesmore » focused on how the microclimate effects of these architectural changes are likely to accumulate over time. Three patterns emerged: (1) scale herbivory reduced leaf area index (LAI) of susceptible trees by 39%, whereas moths had no effect on LAI; (2) scale herbivory increased soil moisture and temperature beneath susceptible trees by 35 and 26%, respectively, whereas moths had no effect; and (3) scale and moth herbivory decreased crown interception of precipitation by 51 and 29%, respectively. From these results, we conclude: (1) the magnitude of scale effects on soil moisture and temperature is large, similar to global change scenarios, and sufficient to drive changes in ecosystem processes. (2) The larger sizes of moth-susceptible trees apparently buffered them from most microclimate effects of herbivory, despite marked changes in crown architecture. (3) The phenotypic expression of susceptibility or resistance to scale insects extends beyond plant-herbivore interactions to the physical environment.« less
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Closed-chamber transepidermal water loss measurement: microclimate, calibration and performance.
Imhof, R E; De Jesus, M E P; Xiao, P; Ciortea, L I; Berg, E P
2009-04-01
The importance of transepidermal water loss (TEWL) as a measure of the skin barrier is well recognized. Currently, the open-chamber method is dominant, but it is increasingly challenged by newer closed-chamber technologies. Whilst there is familiarity with open-chamber characteristics, there is uncertainty about the capabilities of the challengers. The main issues are related to how microclimate affects TEWL measurements. The aim of this paper is to provide a framework for understanding the effects of microclimate on TEWL measurement. Part of the problem is that TEWL measurement is indirect. TEWL is the diffusion of condensed water through the stratum corneum (SC), whereas TEWL methods measure water vapour flux in the air above the SC. This vapour flux depends on (i) the rate of supply of water to the skin surface and (ii) the rate of evaporation of water from the skin surface. Rate (i) is a skin property (TEWL), rate (ii) is a microclimate property. The controlling rate for the combined process is the lower of the above two rates. Therefore, TEWL instruments measure TEWL only when TEWL is the rate-limiting process. Another problem is that SC barrier property and SC hydration are affected by the microclimate adjacent to the skin surface. This is discussed insofar as it affects the measurement of TEWL. The conclusion is that such changes occur on a timescale that is long compared with TEWL measurement times. An important aspect of TEWL measurement is calibration. We present an analysis of the traditional wet-cup method and a new droplet method that is traceable and has been independently verified by a standards laboratory. Finally, we review performance indicators of commercial closed-chamber instruments with reference to open-chamber instruments. The main findings are that TEWL readings correlate well, but there are significant differences in the other aspects of performance.
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Microclimate and development of pressure ulcers and superficial skin changes.
Yusuf, Saldy; Okuwa, Mayumi; Shigeta, Yoshie; Dai, Misako; Iuchi, Terumi; Rahman, Sulaiman; Usman, Awaluddin; Kasim, Sukmawati; Sugama, Junko; Nakatani, Toshio; Sanada, Hiromi
2015-02-01
This study aims to evaluate the microclimate and development of pressure ulcers and superficial skin changes. A prospective cohort study was conducted in an acute care ward in Indonesia. Risk factors for pressure ulcers and superficial skin changes were identified based on the Bergstrom Braden conceptual model. Microclimate data were collected every 3 days for 15 days while the development of pressure ulcers and superficial skin changes was observed every day. Pressure ulcers and superficial skin changes were developed in 20 of the 71 participants. Total mean difference in skin temperature was higher for patients with pressure ulcers and superficial skin changes (0·9 ± 0·6°C) compared with controls (0·6 ± 0·8°C) (P = 0·071). Binary logistic regression predictor values for pressure ulcers and superficial skin changes were 0·111 for type of sheet and 0·347 for Braden Scale results. In conclusion, difference in skin temperature seems to be a predictor for pressure ulcer development and superficial skin changes, while synthetic fibre sheets are able to maintain a beneficial microclimate. © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.
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Assessment of turkey vehicle container microclimate on transit during summer season conditions.
Carvalho, Rafael H; Honorato, Danielle C B; Guarnieri, Paulo D; Soares, Adriana L; Pedrão, Mayka R; Oba, Alexandre; Paião, Fernanda G; Ida, Elza I; Shimokomaki, Massami
2018-06-01
This study evaluated the formed microclimate commercial truck transport practices effects on the turkeys' welfare by measuring Dead on Arrival (DOA) index and pale, soft, and exudative (PSE-like) meat occurrence. The experimental design was entirely randomized in a 6 × 2 factorial arrangements (two truck container compartments × six water shower groups) with birds positioned at superior front (SF), inferior front (IF), superior middle (SM), inferior middle (IM), superior rear (SR), and inferior rear (IR) and two bath treatments: with water shower (WiS) and without water shower (WoS) with eight replications for each treatment. The animals were transported for 95 min' journey from the farm to the slaughterhouse under hot-humidity conditions. The results shown herein indicated the formation of a thermal core at the inferior middle and rear truck container regions, because the heat produced by the birds and the influence of developed microclimate consisting of temperature, relative humidity, and air ventilation. The IM and IR container compartments under the WoS treatment presented the highest (P < 0.01) numbers of PSE-like meat incidence and DOA index values compared with those located at the front under WiS treatment as the consequence of the altered to birds unbearable conditions within the container microclimate in transit. The formed microclimate during the commercial transport practices under hot-humidity conditions affected the bird's welfare consequently turkey meat qualities.
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Effects of urban green infrastructure (UGI) on local outdoor microclimate during the growing season.
Wang, Yafei; Bakker, Frank; de Groot, Rudolf; Wörtche, Heinrich; Leemans, Rik
2015-12-01
This study analyzed how the variations of plant area index (PAI) and weather conditions alter the influence of urban green infrastructure (UGI) on microclimate. To observe how diverse UGIs affect the ambient microclimate through the seasons, microclimatic data were measured during the growing season at five sites in a local urban area in The Netherlands. Site A was located in an open space; sites B, C, and D were covered by different types and configurations of green infrastructure (grove, a single deciduous tree, and street trees, respectively); and site E was adjacent to buildings to study the effects of their façades on microclimate. Hemispherical photography and globe thermometers were used to quantify PAI and thermal comfort at both shaded and unshaded locations. The results showed that groves with high tree density (site B) have the strongest effect on microclimate conditions. Monthly variations in the differences of mean radiant temperature (∆Tmrt) between shaded and unshaded areas followed the same pattern as the PAI. Linear regression showed a significant positive correlation between PAI and ∆Tmrt. The difference of daily average air temperature (∆T a ) between shaded and unshaded areas was also positively correlated to PAI, but with a slope coefficient below the measurement accuracy (±0.5 °C). This study showed that weather conditions can significantly impact the effectiveness of UGI in regulating microclimate. The results of this study can support the development of appropriate UGI measures to enhance thermal comfort in urban areas.
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Developing 3D morphologies for simulating building energy demand in urban microclimates
DOE Office of Scientific and Technical Information (OSTI.GOV)
New, Joshua Ryan; Omitaomu, Olufemi A.; Allen, Melissa R.
In order to simulate the effect of interactions between urban morphology and microclimate on demand for heating and cooling in buildings, we utilize source elevation data to create 3D building geometries at the neighborhood and city scale. Additionally, we use urban morphology concepts to design virtual morphologies for simulation scenarios in an undeveloped land parcel. Using these morphologies, we compute building-energy parameters such as the density for each surface and the frontal area index for each of the buildings to be able to effectively model the microclimate for the urban area.
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[Microclimate and comfortable degree of Shanghai urban open spaces in summer].
Cao, Dan; Zhou, Li-chen; Mao, Yi-wei; Li, Yin; Liu, Yi-ning; Wang, Tian-hou
2008-08-01
Based on the observation data of air temperature, relative humidity, wind speed, and solar radiation from May to August 2006, the regulation effects of five types of open spaces (square, fountain, grassplot, corridor, and woodland) in Shanghai urban districts on the microclimate were analyzed, and discomfort index (DI) was introduced to evaluate the effects of these five types of open spaces on human body' s comfortable degree. The results showed that there existed definite differences in the air temperature and relative humidity among the open spaces, with the mean temperature decreased in the order of square > grassplot > fountain > corridor > woodland, and the mean relative humidity decreased in the order of woodland > corridor > fountain > grassplot > square. The area of the square, the wind speed and direction near the fountain, the grass species on the grass-plot, the width and tree coverage of the corridor, and the tree coverage and canopy height of the woodland had significant correlations with the microclimate parameters of corresponding open spaces. Comparing with other three types of open spaces, woodland and corridor had better regulation effects on the microclimate via shading, decreasing air temperature, and increasing relative humidity.
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NASA Microclimate Cooling Challenges
NASA Technical Reports Server (NTRS)
Trevino, Luis A.
2004-01-01
The purpose of this outline form presentation is to present NASA's challenges in microclimate cooling as related to the spacesuit. An overview of spacesuit flight-rated personal cooling systems is presented, which includes a brief history of cooling systems from Gemini through Space Station missions. The roles of the liquid cooling garment, thermal environment extremes, the sublimator, multi-layer insulation, and helmet visor UV and solar coatings are reviewed. A second section is presented on advanced personal cooling systems studies, which include heat acquisition studies on cooling garments, heat rejection studies on water boiler & radiators, thermal storage studies, and insulation studies. Past and present research and development and challenges are summarized for the advanced studies.
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Hydrothermal assessment of temporal variability in seedbed microclimate
Stuart P. Hardegree; Corey A. Moffet; Gerald N. Flerchinger; Jaepil Cho; Bruce A. Roundy; Thomas A. Jones; Jeremy J. James; Patrick E. Clark; Frederick B. Pierson
2013-01-01
The microclimatic requirements for successful seedling establishment are much more restrictive than those required for adult plant survival. The purpose of the current study was to use hydrothermal germination models and a soil energy and water flux model to evaluate intra- and interannual variability in seedbed microclimate relative to potential germination response...
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Evaluation of Three Commercial Microclimate Cooling Systems
1988-11-01
easily counteracted because of the difficulty of drinking inside protective clothing . Dehydration combined with warm skin and exercise can easily result in...Stress; Exercise ; Thermoregulation 9. ABSTRACT (Continue on reverse if necessary and identify by block number) (OThree commercially available microclimate...cooling systems were evaluated for their abil- ity to reduce heat stress in men exercising in a hot environment while wearing high insula- tive, low
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Fragmentation impairs the microclimate buffering effect of tropical forests.
Ewers, Robert M; Banks-Leite, Cristina
2013-01-01
Tropical forest species are among the most sensitive to changing climatic conditions, and the forest they inhabit helps to buffer their microclimate from the variable climatic conditions outside the forest. However, habitat fragmentation and edge effects exposes vegetation to outside microclimatic conditions, thereby reducing the ability of the forest to buffer climatic variation. In this paper, we ask what proportion of forest in a fragmented ecosystem is impacted by altered microclimate conditions driven by edge effects, and extrapolate these results to the whole Atlantic Forest biome, one of the most disturbed biodiversity hotspots. To address these questions, we collected above and below ground temperature for a full year using temperature sensors placed in forest fragments of different sizes, and at different distances from the forest edge. In the Atlantic forests of Brazil, we found that the buffering effect of forests reduced maximum outside temperatures by one third or more at ground level within a forest, with the buffering effect being stronger below-ground than one metre above-ground. The temperature buffering effect of forests was, however, reduced near forest edges with the edge effect extending up to 20 m inside the forest. The heavily fragmented nature of the Brazilian Atlantic forest means that 12% of the remaining biome experiences altered microclimate conditions. Our results add further information about the extent of edge effects in the Atlantic Forest, and we suggest that maintaining a low perimeter-to-area ratio may be a judicious method for minimizing the amount of forest area that experiences altered microclimatic conditions in this ecosystem.
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Cavity types and microclimate: implications for ecological, evolutionary, and conservation studies.
Amat-Valero, M; Calero-Torralbo, M A; Václav, R; Valera, F
2014-11-01
The abiotic conditions of the immediate environment of organisms are key factors for a better understanding of ecological and evolutionary processes. Yet, information in this regard is biased towards some habitat types, landscapes, and organisms. Here, we present a 2-year comparative study of the microclimatic properties (temperature, relative humidity, and their fluctuation) of three cavity types (nest boxes, cavities in bridges, and burrows in sandy cliffs) in an arid environment. We found marked and consistent months-long differences in microclimate among the three cavity types. Nest boxes were colder than the other cavity types, with temperature oscillations being an order of magnitude higher than in other cavity types. In contrast, microclimate was very stable in burrows and cavities in bridges, the former being generally warmer and drier than the latter. We also discuss the biological implications of microclimatic conditions and its variation in different cavity types by presenting two case studies, namely the temperature-humidity index and water vapor pressure during the hatching period of an endotherm and the chilling period during the diapause of an ectotherm ectoparasite. We stress the need for comparative studies of the same organisms subjected to different microclimates given the important ecological, evolutionary, and conservation implications.
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Cooling Effectiveness of a Hybrid Microclimate Garment
1988-04-01
ELEMENT NO . NO . NO . JCCESSION NO .63747 D669 35 Cooling Effectiveness of a Hybrid Microclimate Garment (U) 12. PERSONAL AUTHOR(S) Barry S...be arranged. Therefore, no direct measurement of the cooling rate achieved by the air garments was obtained. After calculation of the liquid cooling...Cooling Performance. There was no significant difference between the levels of heat removed by the liquid and hybrid-liquid garments . The measured
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Microclimate Cooling Systems: A Shipboard Evaluation of Commercial Models
1988-04-01
NCTRF), under contract to the Navy SciencI Assistance Program (NSAP), evaluated the feasibility of using commercial microclimate coolin9" systems (MCS...exterior of the air distribution vest be covered with a fire-retardant material similar to the type used in this evaluation. The results of this evaluation
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Fragmentation Impairs the Microclimate Buffering Effect of Tropical Forests
Ewers, Robert M.; Banks-Leite, Cristina
2013-01-01
Background Tropical forest species are among the most sensitive to changing climatic conditions, and the forest they inhabit helps to buffer their microclimate from the variable climatic conditions outside the forest. However, habitat fragmentation and edge effects exposes vegetation to outside microclimatic conditions, thereby reducing the ability of the forest to buffer climatic variation. In this paper, we ask what proportion of forest in a fragmented ecosystem is impacted by altered microclimate conditions driven by edge effects, and extrapolate these results to the whole Atlantic Forest biome, one of the most disturbed biodiversity hotspots. To address these questions, we collected above and below ground temperature for a full year using temperature sensors placed in forest fragments of different sizes, and at different distances from the forest edge. Principal Findings In the Atlantic forests of Brazil, we found that the buffering effect of forests reduced maximum outside temperatures by one third or more at ground level within a forest, with the buffering effect being stronger below-ground than one metre above-ground. The temperature buffering effect of forests was, however, reduced near forest edges with the edge effect extending up to 20 m inside the forest. The heavily fragmented nature of the Brazilian Atlantic forest means that 12% of the remaining biome experiences altered microclimate conditions. Conclusions Our results add further information about the extent of edge effects in the Atlantic Forest, and we suggest that maintaining a low perimeter-to-area ratio may be a judicious method for minimizing the amount of forest area that experiences altered microclimatic conditions in this ecosystem. PMID:23483976
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Seidelmann, Katrin N; Scherer-Lorenzen, Michael; Niklaus, Pascal A
2016-01-01
Effects of tree species diversity on decomposition can operate via a multitude of mechanism, including alterations of microclimate by the forest canopy. Studying such effects in natural settings is complicated by the fact that topography also affects microclimate and thus decomposition, so that effects of diversity are more difficult to isolate. Here, we quantified decomposition rates of standard litter in young subtropical forest stands, separating effects of canopy tree species richness and topography, and quantifying their direct and micro-climate-mediated components. Our litterbag study was carried out at two experimental sites of a biodiversity-ecosystem functioning field experiment in south-east China (BEF-China). The field sites display strong topographical heterogeneity and were planted with tree communities ranging from monocultures to mixtures of 24 native subtropical tree species. Litter bags filled with senescent leaves of three native tree species were placed from Nov. 2011 to Oct. 2012 on 134 plots along the tree species diversity gradient. Topographic features were measured for all and microclimate in a subset of plots. Stand species richness, topography and microclimate explained important fractions of the variations in litter decomposition rates, with diversity and topographic effects in part mediated by microclimatic changes. Tree stands were 2-3 years old, but nevertheless tree species diversity explained more variation (54.3%) in decomposition than topography (7.7%). Tree species richness slowed litter decomposition, an effect that slightly depended on litter species identity. A large part of the variance in decomposition was explained by tree species composition, with the presence of three tree species playing a significant role. Microclimate explained 31.4% of the variance in decomposition, and was related to lower soil moisture. Within this microclimate effect, species diversity (without composition) explained 8.9% and topography 34.4% of
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Seidelmann, Katrin N.; Scherer-Lorenzen, Michael; Niklaus, Pascal A.
2016-01-01
Effects of tree species diversity on decomposition can operate via a multitude of mechanism, including alterations of microclimate by the forest canopy. Studying such effects in natural settings is complicated by the fact that topography also affects microclimate and thus decomposition, so that effects of diversity are more difficult to isolate. Here, we quantified decomposition rates of standard litter in young subtropical forest stands, separating effects of canopy tree species richness and topography, and quantifying their direct and micro-climate-mediated components. Our litterbag study was carried out at two experimental sites of a biodiversity-ecosystem functioning field experiment in south-east China (BEF-China). The field sites display strong topographical heterogeneity and were planted with tree communities ranging from monocultures to mixtures of 24 native subtropical tree species. Litter bags filled with senescent leaves of three native tree species were placed from Nov. 2011 to Oct. 2012 on 134 plots along the tree species diversity gradient. Topographic features were measured for all and microclimate in a subset of plots. Stand species richness, topography and microclimate explained important fractions of the variations in litter decomposition rates, with diversity and topographic effects in part mediated by microclimatic changes. Tree stands were 2–3 years old, but nevertheless tree species diversity explained more variation (54.3%) in decomposition than topography (7.7%). Tree species richness slowed litter decomposition, an effect that slightly depended on litter species identity. A large part of the variance in decomposition was explained by tree species composition, with the presence of three tree species playing a significant role. Microclimate explained 31.4% of the variance in decomposition, and was related to lower soil moisture. Within this microclimate effect, species diversity (without composition) explained 8.9% and topography 34.4% of
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Sampling and modeling riparian forest structure and riparian microclimate
Bianca N.I. Eskelson; Paul D. Anderson; Hailemariam Temesgen
2013-01-01
Riparian areas are extremely variable and dynamic, and represent some of the most complex terrestrial ecosystems in the world. The high variability within and among riparian areas poses challenges in developing efficient sampling and modeling approaches that accurately quantify riparian forest structure and riparian microclimate. Data from eight stream reaches that are...
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The Importance of Biologically Relevant Microclimates in Habitat Suitability Assessments
Varner, Johanna; Dearing, M. Denise
2014-01-01
Predicting habitat suitability under climate change is vital to conserving biodiversity. However, current species distribution models rely on coarse scale climate data, whereas fine scale microclimate data may be necessary to assess habitat suitability and generate predictive models. Here, we evaluate disparities between temperature data at the coarse scale from weather stations versus fine-scale data measured in microhabitats required for a climate-sensitive mammal, the American pika (Ochotona princeps). We collected two years of temperature data in occupied talus habitats predicted to be suitable (high elevation) and unsuitable (low elevation) by the bioclimatic envelope approach. At low elevations, talus surface and interstitial microclimates drastically differed from ambient temperatures measured on-site and at a nearby weather station. Interstitial talus temperatures were frequently decoupled from high ambient temperatures, resulting in instantaneous disparities of over 30°C between these two measurements. Microhabitat temperatures were also highly heterogeneous, such that temperature measurements within the same patch of talus were not more correlated than measurements at distant patches. An experimental manipulation revealed that vegetation cover may cool the talus surface by up to 10°C during the summer, which may contribute to this spatial heterogeneity. Finally, low elevation microclimates were milder and less variable than typical alpine habitat, suggesting that, counter to species distribution model predictions, these seemingly unsuitable habitats may actually be better refugia for this species under climate change. These results highlight the importance of fine-scale microhabitat data in habitat assessments and underscore the notion that some critical refugia may be counterintuitive. PMID:25115894
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The importance of biologically relevant microclimates in habitat suitability assessments.
Varner, Johanna; Dearing, M Denise
2014-01-01
Predicting habitat suitability under climate change is vital to conserving biodiversity. However, current species distribution models rely on coarse scale climate data, whereas fine scale microclimate data may be necessary to assess habitat suitability and generate predictive models. Here, we evaluate disparities between temperature data at the coarse scale from weather stations versus fine-scale data measured in microhabitats required for a climate-sensitive mammal, the American pika (Ochotona princeps). We collected two years of temperature data in occupied talus habitats predicted to be suitable (high elevation) and unsuitable (low elevation) by the bioclimatic envelope approach. At low elevations, talus surface and interstitial microclimates drastically differed from ambient temperatures measured on-site and at a nearby weather station. Interstitial talus temperatures were frequently decoupled from high ambient temperatures, resulting in instantaneous disparities of over 30 °C between these two measurements. Microhabitat temperatures were also highly heterogeneous, such that temperature measurements within the same patch of talus were not more correlated than measurements at distant patches. An experimental manipulation revealed that vegetation cover may cool the talus surface by up to 10 °C during the summer, which may contribute to this spatial heterogeneity. Finally, low elevation microclimates were milder and less variable than typical alpine habitat, suggesting that, counter to species distribution model predictions, these seemingly unsuitable habitats may actually be better refugia for this species under climate change. These results highlight the importance of fine-scale microhabitat data in habitat assessments and underscore the notion that some critical refugia may be counterintuitive.
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NASA Astrophysics Data System (ADS)
Brown, Robert Douglas
Several components of a system for quantitative application of climatic statistics to landscape planning and design (CLIMACS) have been developed. One component model (MICROSIM) estimated the microclimate at the top of a remote crop using physically-based models and inputs of weather station data. Temperatures at the top of unstressed, uniform crops on flat terrain within 1600 m of a recording weather station were estimated within 1.0 C 96% of the time for a corn crop and 92% of the time for a soybean crop. Crop top winds were estimated within 0.4 m/s 92% of the time for corn and 100% of the time for soybean. This is of sufficient accuracy for application in landscape planning and design models. A physically-based model (COMFA) was developed for the determination of outdoor human thermal comfort from microclimate inputs. Estimated versus measured comfort levels in a wide range of environments agreed with a correlation coefficient of r = 0.91. Using these components, the CLIMACS concept has been applied to a typical planning example. Microclimate data were generated from weather station information using MICROSIM, then input to COMFA and to a house energy consumption model called HOTCAN to derive quantitative climatic justification for design decisions.
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Structure of the microclimate at a woodland/parking-lot interface
David R. Miller
1977-01-01
Radiation balances and vertical and horizontal profiles of air temperature, vapor pressure and wind speed were measured across the interface of a large asphalt parking lot and an 18-m-tall Quercus velutina forest. The partitioning of available energy over the adjacent areas shows steep gradients between the parking lot and forest microclimates....
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Pan, D; Chan, M; Deng, S; Xia, L; Xu, X
2011-11-01
This article reports on two numerical studies on the microclimate around, and the thermal neutrality of, a sleeping person in a space installed with a displacement ventilation system. The development of a sleeping computational thermal manikin (SCTM) placed in a space air-conditioned by a displacement ventilation system is first described. This is followed by reporting the results of the first numerical study on the microclimate around the SCTM, including air temperature and velocity distributions and the heat transfer characteristics. Then the outcomes of the other numerical study on the thermal neutrality of a sleeping person are presented, including the thermal neutrality for a naked sleeping person and the effects of the total insulation value of a bedding system on the thermal neutrality of a sleeping person. STATEMENT OF RELEVANCE: The thermal environment would greatly affect the sleep quality of human beings. Through developing a SCTM, the microclimate around a sleeping person has been numerically studied. The thermal neutral environment may then be predicted and contributions to improved sleep quality may be made.
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Crum, Steven M; Shiflett, Sheri A; Jenerette, G Darrel
2017-09-15
Many cities are increasing vegetation in part due to the potential for microclimate cooling. However, the magnitude of vegetation cooling and sensitivity to mesoclimate and meteorology are uncertain. To improve understanding of the variation in vegetation's influence on urban microclimates we asked: how do meso- and regional-scale drivers influence the magnitude and timing of vegetation-based moderation on summertime air temperature (T a ), relative humidity (RH) and heat index (HI) across dryland cities? To answer this question we deployed a network of 180 temperature sensors in summer 2015 over 30 high- and 30 low-vegetated plots in three cities across a coastal to inland to desert climate gradient in southern California, USA. In a followup study, we deployed a network of temperature and humidity sensors in the inland city. We found negative T a and HI and positive RH correlations with vegetation intensity. Furthermore, vegetation effects were highest in evening hours, increasing across the climate gradient, with reductions in T a and increases in RH in low-vegetated plots. Vegetation increased temporal variability of T a , which corresponds with increased nighttime cooling. Increasing mean T a was associated with higher spatial variation in T a in coastal cities and lower variation in inland and desert cities, suggesting a climate dependent switch in vegetation sensitivity. These results show that urban vegetation increases spatiotemporal patterns of microclimate with greater cooling in warmer environments and during nighttime hours. Understanding urban microclimate variation will help city planners identify potential risk reductions associated with vegetation and develop effective strategies ameliorating urban microclimate. Published by Elsevier Ltd.
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Riparian microclimate and stream temperature: thinning and buffer-width influences
Paul D. Anderson
2013-01-01
Th inning of 30- to 70-year-old Douglas-fir (Pseudotsuga menziesii) stands is a common silvicultural activity on federal forest lands in Washington and Oregon west of the Cascade Range crest. Decreases in forest cover lead to alterations of site energy balances resulting in changes to understory and stream channel microclimates. Uncut vegetative...
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Cities as Water Supply Catchments to deliver microclimate benefits
NASA Astrophysics Data System (ADS)
Beringer, J.; Tapper, N. J.; Coutts, A.; Loughnan, M.
2010-12-01
Urban development extensively modifies the natural hydrology, biodiversity, carbon balance, air quality and climate of the local and regional environment mainly due to increased impervious surface area (roads, pavements, roofs, etc.). Impervious surface are a legacy of urban infrastructure planning based on a ‘drained city’ to minimise flood risk. The result is a modification of the microclimate around buildings and on a city scale results in the Urban Heat Island (UHI) effect where the urban areas are much hotter than the surrounding rural areas. Such heating comes on top of 20th century human induced climate change, namely decreased rainfall and higher temperatures. Drought conditions have triggered water restrictions in many Australian cities that have dramatically reduced ‘irrigation’ in urban areas. Ironically the drying influence from climate change has now been compounded by the drying influence of water restrictions and the efficient removal of stormwater resulting in desert like climates during summer. This will be further exacerbated by the projected increases in hot days, extreme hot days, heat waves, etc. In turn this excessive heating will compromise the health and liveability of urban dwellers. Stormwater is a potential critical resource that could be used to keep water in the landscape to irrigate urban areas to improve urban micro-climates, sustain vegetation and provide other multiple benefits to create more liveable and resilient urban environments. In Australia's major cities, stormwater harvesting has the potential to provide a low cost, low energy, fit-for-purpose source of water to help secure city supplies. Stormwater reuse not only provides a potential mitigation tool for the UHI and global climate change but has multiple benefits to provide resilience such as 1) Improved human thermal comfort to reduce heat related stress and mortality, 2) Healthy and productive vegetation and increased carbon sequestration, 3) Decreased stormwater
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Thapa, Sushil; Stewart, Bob A; Xue, Qingwu; Chen, Yuanquan
2017-01-01
Cultivar selection, planting geometry, and plant population are the key factors determining grain sorghum yields in water deficit areas. The objective of this study was to investigate whether clump geometry (three plants clustered) improves microclimate within crop canopy when plants are grown under varying water levels. In a 2-yr sorghum (Sorghum bicolor L. Moench) greenhouse study, plants were grown at two geometries (clump and conventional evenly spaced planting, ESP), two water levels (high and low, representing well-watered and water-limited condition, respectively), and three soil surface treatments (lid covered, straw-mulched, and bare). Air temperature and relative humidity (RH) within the plant canopy were measured every five minutes at different growth stages. Mean vapor pressure deficits (VPDs) within the clumps were consistently lower than those for ESPs, indicating that clumps improved the microclimate. Clumps had significantly higher harvest index (HI) compared to ESPs (0.48 vs. 0.43), which was largely due to clumps having an average of 0.4 tillers per plant compared to 1.2 tillers per plant for ESPs. Grain yield in the current study was similar between clumps and ESPs. However, our results suggest that improved microclimate was likely a reason for clumps producing significantly higher grain yields compared to ESPs in previous studies.
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Manipulating plant geometry to improve microclimate, grain yield, and harvest index in grain sorghum
Stewart, Bob A.; Xue, Qingwu; Chen, Yuanquan
2017-01-01
Cultivar selection, planting geometry, and plant population are the key factors determining grain sorghum yields in water deficit areas. The objective of this study was to investigate whether clump geometry (three plants clustered) improves microclimate within crop canopy when plants are grown under varying water levels. In a 2-yr sorghum (Sorghum bicolor L. Moench) greenhouse study, plants were grown at two geometries (clump and conventional evenly spaced planting, ESP), two water levels (high and low, representing well-watered and water-limited condition, respectively), and three soil surface treatments (lid covered, straw-mulched, and bare). Air temperature and relative humidity (RH) within the plant canopy were measured every five minutes at different growth stages. Mean vapor pressure deficits (VPDs) within the clumps were consistently lower than those for ESPs, indicating that clumps improved the microclimate. Clumps had significantly higher harvest index (HI) compared to ESPs (0.48 vs. 0.43), which was largely due to clumps having an average of 0.4 tillers per plant compared to 1.2 tillers per plant for ESPs. Grain yield in the current study was similar between clumps and ESPs. However, our results suggest that improved microclimate was likely a reason for clumps producing significantly higher grain yields compared to ESPs in previous studies. PMID:28264051
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Drone and Worker Brood Microclimates Are Regulated Differentially in Honey Bees, Apis mellifera.
Li, Zhiyong; Huang, Zachary Y; Sharma, Dhruv B; Xue, Yunbo; Wang, Zhi; Ren, Bingzhong
2016-01-01
Honey bee (Apis mellifera) drones and workers show differences in morphology, physiology, and behavior. Because the functions of drones are more related to colony reproduction, and those of workers relate to both survival and reproduction, we hypothesize that the microclimate for worker brood is more precisely regulated than that of drone brood. We assessed temperature and relative humidity (RH) inside honey bee colonies for both drone and worker brood throughout the three-stage development period, using digital HOBO® Data Loggers. The major findings of this study are that 1) both drone and worker castes show the highest temperature for eggs, followed by larvae and then pupae; 2) temperature in drones are maintained at higher precision (smaller variance) in drone eggs and larvae, but at a lower precision in pupae than the corresponding stages of workers; 3) RH regulation showed higher variance in drone than workers across all brood stages; and 4) RH regulation seems largely due to regulation by workers, as the contribution from empty honey combs are much smaller compared to that from adult workers. We conclude that honey bee colonies maintain both temperature and humidity actively; that the microclimate for sealed drone brood is less precisely regulated than worker brood; and that combs with honey contribute very little to the increase of RH in honey bee colonies. These findings increase our understanding of microclimate regulation in honey bees and may have implications for beekeeping practices.
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Drone and Worker Brood Microclimates Are Regulated Differentially in Honey Bees, Apis mellifera
Li, Zhiyong; Huang, Zachary Y.; Sharma, Dhruv B.; Xue, Yunbo; Wang, Zhi; Ren, Bingzhong
2016-01-01
Background Honey bee (Apis mellifera) drones and workers show differences in morphology, physiology, and behavior. Because the functions of drones are more related to colony reproduction, and those of workers relate to both survival and reproduction, we hypothesize that the microclimate for worker brood is more precisely regulated than that of drone brood. Methodology/Principal Findings We assessed temperature and relative humidity (RH) inside honey bee colonies for both drone and worker brood throughout the three-stage development period, using digital HOBO® Data Loggers. The major findings of this study are that 1) both drone and worker castes show the highest temperature for eggs, followed by larvae and then pupae; 2) temperature in drones are maintained at higher precision (smaller variance) in drone eggs and larvae, but at a lower precision in pupae than the corresponding stages of workers; 3) RH regulation showed higher variance in drone than workers across all brood stages; and 4) RH regulation seems largely due to regulation by workers, as the contribution from empty honey combs are much smaller compared to that from adult workers. Conclusions/Significance We conclude that honey bee colonies maintain both temperature and humidity actively; that the microclimate for sealed drone brood is less precisely regulated than worker brood; and that combs with honey contribute very little to the increase of RH in honey bee colonies. These findings increase our understanding of microclimate regulation in honey bees and may have implications for beekeeping practices. PMID:26882104
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A microclimate study on hypogea environments of ancient roman building.
Scatigno, C; Gaudenzi, S; Sammartino, M P; Visco, G
2016-10-01
Roman hypogea, vernacular settlements or crypts, are underground places characterised by specific and unique challenges (RH<90% and almost constant temperature throughout the whole year) related to their relative isolation from the outdoor environment. These sites often require adequate monitoring tools providing complete environmental information in order to carry out appropriate strategies for scheduling routine maintenance and designing suitable layouts for their preservation. In this work we present the results of a carefully planned thermo-hygrometric monitoring campaign conducted in a peculiar Roman building (130CE), the "Casa di Diana" Mithraeum, sited in Ostia Antica (archaeological site, Rome-Italy), with the aim of characterising the indoor environment as the structure suffers of several conservation problems (biocolonisation, efflorescences, evaporating and condensing cycle for wall-building materials). The campaign involving multipoint continuous measurement was carefully planned to better describe this micro-clime. In addition to underground environmental data available in literature, we have also performed, as a checkpoint control, a thermo-hygrometric monitoring campaign in the "Terme di Mitra" Hypogeum, a few meters from the "Casa di Diana". The recorded data was analysed by multivariate statistical and chemometric analyses. The results brought to light the presence of different microclimates (three areas) within a single Mithraeum: a room (pre-Mithraeum) and an area (Mithraeum: 2-4m) present a thermo-hygrometric environmental behaviour in accordance with a semi-confined environment, another area (Mithraeum: 1-2m) behaves accordingly with underground environments (although it cannot be described as such), and the last area (Mithraeum: 0-1m) where was recording RH values close to saturation (96-99%), associated with non-ventilated areas where the rising damp is "held" and not dispersed, describing an own micro-clime, comparable to a "small greenhouse
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ON THE IMPACT OF THE HUMAN (CHILD) MICROCLIMATE ON PASSIVE AEROSOL MONITOR PERFORMANCE
Research into the wind microclimate and its effect on the accuracy and effectiveness of passive aerosol monitors is expanding as the importance of personal monitoring versus regional monitoring increases. The important phenomena for investigation include thermal and dynamic eff...
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Effect of moisture transport on microclimate under T-shirts.
Dai, Xiao-Qun; Imamura, Ritsuko; Liu, Guo-Lian; Zhou, Fu-Ping
2008-09-01
Water transport through garments has influence on the microclimate between the garments and the body beneath; thus the thermal comfort feeling for the wearer. Soybean protein fiber (SPF), a new type environmental fiber, which has been reported to be superior in water transfer, is often blended with cotton to improve the water transport property. In this paper, T-shirts made of this SPF/cotton blended fabric were focused in comparison with T-shirts made of cotton fabric. Wicking and immersion tests were carried out on the two types of fabrics to investigate the water transport and absorption properties, respectively; wear trials of T-shirts made of the fabrics were also conducted. Comparing with the cotton fabric which had better water absorptive property, it was found that the blended fabric with superior wicking ability could not only delay the increase of the vapor pressure under the T-shirt at the beginning of the exercise, but also help to keep it lower through the exercise significantly, and also kept the skin temperature under the T-shirt lower. It was made clear that it is the water transfer property rather than the water absorption property helps to take away sweat quickly and prevents the increase of the humidity and temperature at skin surface, thus maintaining a comfort microclimate under garments.
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Li, Yingnan; Kang, Wanmo; Han, Yiwen; Song, Youngkeun
2018-01-23
Fragmented forests generate a variety of forest edges, leading to microclimates in the edge zones that differ from those in the forest interior. Understanding microclimatic variation is an important consideration for managers because it helps when making decisions about how to restrict the extent of edge effects. Thus, our study attempted to characterize the changing microclimate features at an urban forest edge located on Mt. Gwanak, Seoul, South Korea. We examined edge effects on air temperature, relative humidity, soil temperature, soil moisture, and photosynthetically active radiation (PAR) during the hottest three consecutive days in August 2016. Results showed that each variable responded differently to the edge effects. This urban forest edge had an effect on temporal changes at a diurnal scale in all microclimate variables, except soil moisture. In addition, all variables except relative humidity were significantly influenced by the edge effect up to 15 m inward from the forest boundary. The relative humidity fluctuated the most and showed the deepest extent of the edge effect. Moreover, the edge widths calculated from the relative humidity and air temperature both peaked in the late afternoon (16:00 h). Our findings provide a reference for forest managers in designing urban forest zones and will contribute to the conservation of fragmented forests in urban areas.
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Li, Ying-Han; Wang, Jun-Jian; Chen, Xue; Sun, Jian-Lin; Zeng, Hui
2011-02-01
Based on field survey and landscape pattern analysis, this paper studied the effects of green space vegetation canopy on the microclimate in three typical residential quarters in Shenzhen City. In each of the residential quarters, 22-26 points were chosen for meteorological observation; and around each of the observation points, a 20 m x 20 m quadrat was installed, with each quadrat divided into two different patches, one covered by vegetation canopy and the another no-covered. The patch density index (D(p)) and contagion index (CONTAG) in each quadrat were calculated to analyze the relationships between vegetation canopy pattern index and microclimate in each point. The results showed that the green space vegetation canopy pattern in Shenzhen had significant regulation effect on temperature and humidity. The cooling effect was mainly from the shading effect of vegetation, and also, correlated with vegetation quantity. The increase in the CONTAG of bare surface had obvious negative effects on the regulation effect of vegetation on microclimate. The regulation capability of green space vegetation on the temperature and humidity in residential quarters mainly came from tall arbor species.
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NASA Astrophysics Data System (ADS)
Finaeva, O.
2017-11-01
The article represents a brief analysis of factors that influence the development of an urban green space system: territorial and climatic conditions, cultural and historical background as well as the modern strategy of historic cities development. The introduction defines the concept of urban greening, green spaces and green space distribution. The environmental parameters influenced by green spaces are determined. By the example of Italian cities the principles of the urban greening system development are considered: the historical aspects of formation of the urban greening system in Italian cities are analyzed, the role of green spaces in the formation of the urban environment structure and the creation of a favorable microclimate is determined, and a set of measures aimed at its improvement is highlighted. The modern principles of urban greening systems development and their characteristic features are considered. Special attention is paid to the interrelation of architectural and green structures in the formation of a favorable microclimate and psychological comfort in the urban environment; various methods of greening are considered by the example of existing architectural complexes depending on the climate of the area and the landscape features. The examples for the choice of plants and the application of compositional techniques are given. The results represent the basic principles of developing an urban green spaces system. The conclusion summarizes the techniques aimed at the microclimate improvement in the urban environment.
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NASA Astrophysics Data System (ADS)
Yahia, Moohammed Wasim; Johansson, Erik; Thorsson, Sofia; Lindberg, Fredrik; Rasmussen, Maria Isabel
2018-03-01
Due to the complexity of built environment, urban design patterns considerably affect the microclimate and outdoor thermal comfort in a given urban morphology. Variables such as building heights and orientations, spaces between buildings, plot coverage alter solar access, wind speed and direction at street level. To improve microclimate and comfort conditions urban design elements including vegetation and shading devices can be used. In warm-humid Dar es Salaam, the climate consideration in urban design has received little attention although the urban planning authorities try to develop the quality of planning and design. The main aim of this study is to investigate the relationship between urban design, urban microclimate, and outdoor comfort in four built-up areas with different morphologies including low-, medium-, and high-rise buildings. The study mainly concentrates on the warm season but a comparison with the thermal comfort conditions in the cool season is made for one of the areas. Air temperature, wind speed, mean radiant temperature (MRT), and the physiologically equivalent temperature (PET) are simulated using ENVI-met to highlight the strengths and weaknesses of the existing urban design. An analysis of the distribution of MRT in the areas showed that the area with low-rise buildings had the highest frequency of high MRTs and the lowest frequency of low MRTs. The study illustrates that areas with low-rise buildings lead to more stressful urban spaces than areas with high-rise buildings. It is also shown that the use of dense trees helps to enhance the thermal comfort conditions, i.e., reduce heat stress. However, vegetation might negatively affect the wind ventilation. Nevertheless, a sensitivity analysis shows that the provision of shade is a more efficient way to reduce PET than increases in wind speed, given the prevailing sun and wind conditions in Dar es Salaam. To mitigate heat stress in Dar es Salaam, a set of recommendations and guidelines on
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Yahia, Moohammed Wasim; Johansson, Erik; Thorsson, Sofia; Lindberg, Fredrik; Rasmussen, Maria Isabel
2018-03-01
Due to the complexity of built environment, urban design patterns considerably affect the microclimate and outdoor thermal comfort in a given urban morphology. Variables such as building heights and orientations, spaces between buildings, plot coverage alter solar access, wind speed and direction at street level. To improve microclimate and comfort conditions urban design elements including vegetation and shading devices can be used. In warm-humid Dar es Salaam, the climate consideration in urban design has received little attention although the urban planning authorities try to develop the quality of planning and design. The main aim of this study is to investigate the relationship between urban design, urban microclimate, and outdoor comfort in four built-up areas with different morphologies including low-, medium-, and high-rise buildings. The study mainly concentrates on the warm season but a comparison with the thermal comfort conditions in the cool season is made for one of the areas. Air temperature, wind speed, mean radiant temperature (MRT), and the physiologically equivalent temperature (PET) are simulated using ENVI-met to highlight the strengths and weaknesses of the existing urban design. An analysis of the distribution of MRT in the areas showed that the area with low-rise buildings had the highest frequency of high MRTs and the lowest frequency of low MRTs. The study illustrates that areas with low-rise buildings lead to more stressful urban spaces than areas with high-rise buildings. It is also shown that the use of dense trees helps to enhance the thermal comfort conditions, i.e., reduce heat stress. However, vegetation might negatively affect the wind ventilation. Nevertheless, a sensitivity analysis shows that the provision of shade is a more efficient way to reduce PET than increases in wind speed, given the prevailing sun and wind conditions in Dar es Salaam. To mitigate heat stress in Dar es Salaam, a set of recommendations and guidelines on
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Hetem, Robyn S; Strauss, W Maartin; Fick, Linda G; Maloney, Shane K; Meyer, Leith C R; Shobrak, Mohammed; Fuller, Andrea; Mitchell, Duncan
2012-12-01
Predicting whether behaviour could buffer the effects of climate change on long-lived mammals requires a better understanding of the long-term behavioural responses of mammals to environmental stress. Using biologging, we measured locomotor activity and microclimate selection, over eight months, in five Arabian oryx (Oryx leucoryx) living free in a Saudi Arabian desert. The oryx displayed seasonal flexibility in activity patterns, shifting from a continuous 24-h activity pattern with crepuscular peaks in cooler months to a predominantly nocturnal activity pattern during the hottest months, without reducing the total 24-h activity level. The proportion of total 24-h activity that occurred during daylight hours was just 29±8% during the hottest months, versus 53±8% (mean±SD, n=5 oryx) in the other months. The attenuation in diurnal activity levels during the hot months was accompanied by the selection of cooler microclimates, presumably via shade seeking, during the heat of the day. Analysis of miniature black globe (miniglobe) temperature from a remote sensor on the collar of two female animals revealed that oryx selected microclimates cooler than the microclimates in direct sun at higher environmental heat loads across all periods, but with enhanced efficiency during the dry periods. We have quantified activity re-assignment and microclimate selection as responses to hot arid conditions in a free-living artiodactyl. Such flexible behavioural processes may act to buffer the adverse effects of the progressively hotter and drier conditions predicted to occur with climate change. Copyright © 2012 Elsevier GmbH. All rights reserved.
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[Effects of land use type on diurnal dynamics of environment microclimate in Karst zone].
Li, Sheng; Ren, Hua-Dong; Yao, Xiao-Hua; Zhang, Shou-Gong
2009-02-01
In June 2007, the diurnal dynamics of light intensity, air temperature, air relative humidity, soil temperature, and surface soil (0-5 cm) water content of five land use types in the typical Karst zone of Lingyun City in Guangxi Zhuang Autonomous Region were observed. The results showed that different land use types altered the composition, coverage, and height of aboveground vegetation, which in turn changed the environment microclimate to different degree. The microclimate quality was in the order of forestland > shrub land > grassland > farmland > rock land. On rock land, the light intensity, air temperature, air relative humidity, soil temperature, and soil water content were higher, and the diurnal variation of the five climatic factors was notable, with the microclimatic conditions changed towards drier and hotter. Compared with those on rock land, the light intensity on forestland, shrub land, grassland, and farmland decreased by 96.4%, 52.0%, 17.0% and 44.2%, air temperature decreased by 30.1%, 20.2%, 12.7% and 17.8%, air relative humidity increased by 129.2%, 57.2%, 18.0% and 41.2%, soil temperature decreased by 11.5%, 8%, 2.5% and 5.5%, and soil water content increased by 42.6%, 33.2%, 15.7% and 14.0%, respectively. The five climatic factors on forestland and shrub land had lesser fluctuation, with the microclimate tended to cool and wet. Light intensity, air temperature, and soil temperature correlated positively with each other, and had negative correlations with air relative humidity and soil water content. A positive correlation was observed between air temperature and soil water content.
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Hmamouch, Asmae; El Alem, Mahmoud Mohamed; Hakkour, Maryam; Amarir, Fatima; Daghbach, Hassan; Habbari, Khalid; Fellah, Hajiba; Bekhti, Khadija; Sebti, Faiza
2017-02-22
Cutaneous leishmaniasis (CL) is widely distributed in Morocco where its geographical range and incidence are related to environmental factors. This study aimed to examine the impact of several factors on the distribution of CL in Boulemane Province, which is characterized by several microclimates, and to identify the Leishmania species circulating in these areas. Ordinary least squares regression (OLSR) analysis was performed to study the impact of poverty, vulnerability, population density, urbanization and bioclimatic factors on the distribution of CL in this province. Molecular characterization of parasites was performed using a previously described PCR-RFLP method targeting the ITS1 of ribosomal DNA of Leishmania. A total of 1009 cases were declared in Boulemane Province between the years 2000 and 2015 with incidences fluctuating over the years (P = 0.007). Analyzing geographical maps of the study region identified four unique microclimate areas; sub-humid, semi-arid, arid and Saharan. The geographical distribution and molecular identification of species shows that the Saharan microclimate, characterized by the presence of Leishmania major was the most affected (47.78%) followed by semi-arid area where Leishmania tropica was identified in three districts. Among several environmental factors included in the study, poverty had the greatest influence on the spatial extension of the disease in this province. The incidence of CL in Boulemane Province varies between microclimate areas, and environmental factors partly explain this variation. However, the existence of CL in the most affected districts is mainly related to poverty, population movement and human behavior. To our knowledge, this the first study utilizing molecular techniques to confirm L. tropica and L. major as the causative agents of CL in Boulemane Province. Our findings indicate that the spatial and temporal distribution of CL in Boulemane Province is strongly related to poverty and population
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Peng, G H
1990-05-01
Experiments were made to ascertain the effects of covering windowpane with plastic film in Hulunbeir region on microclimate and sunshine intensity in the living room. It was found that a good regulative effect on the room microclimate resulted by covering the windowpane with plastic film in the cold region. The room temperature rose distinctly. No evident effects were found on ultra-violet radiation and illumination. But the concentration of carbon dioxide increased to some extent. Attention should be paid to ventilation of the room.
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NASA Astrophysics Data System (ADS)
Karvatte, Nivaldo; Klosowski, Elcio Silvério; de Almeida, Roberto Giolo; Mesquita, Eduardo Eustáquio; de Oliveira, Caroline Carvalho; Alves, Fabiana Villa
2016-12-01
The objective of this paper was to perform a microclimate evaluation and determine the indexes of thermal comfort indexes, in sun and shade, in integrated crop-livestock-forest systems with different arrangements of eucalyptus and native trees, in the Brazilian Midwest. The experiment was conducted at Embrapa Beef Cattle in Campo Grande, state of Mato Grosso do Sul, Brazil, from July to September 2013. The evaluations were conducted on four consecutive days, from 8:00 a.m. to 5:00 p.m., local time (GMT -4:00), with 1 hour intervals, recording the microclimate parameters: air temperature (°C), black globe temperature (°C), wet bulb temperature (°C), relative humidity (%), and wind speed (m.s-1), for the subsequent calculation of the Temperature and Humidity Index, the Black Globe Temperature and Humidity Index, and the Radiant Thermal Load. The largest changes in microclimate parameters were found in the full sun, between 12:00 p.m. and 1:00 p.m., in less dense eucalyptus system, followed by the scattered native trees system, resulting in a maximum Temperature and Humidity Index of 81, Black Globe Temperature and Humidity Index of 88 and Radiant Thermal Load of 794 W m-2. Therefore, it is observed that with the presence of trees in pastures were possible reductions of up to 3.7 % in Temperature and Humidity Index, 10.2 % in the Black Globe Temperature and Humidity Index, and 28.3 % of the Radiant Thermal Load in the shade. Thus, one can conclude that the presence of trees and their arrangement in the systems provide better microclimate conditions and animal thermal comfort in pastures.
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Karvatte, Nivaldo; Klosowski, Elcio Silvério; de Almeida, Roberto Giolo; Mesquita, Eduardo Eustáquio; de Oliveira, Caroline Carvalho; Alves, Fabiana Villa
2016-12-01
The objective of this paper was to perform a microclimate evaluation and determine the indexes of thermal comfort indexes, in sun and shade, in integrated crop-livestock-forest systems with different arrangements of eucalyptus and native trees, in the Brazilian Midwest. The experiment was conducted at Embrapa Beef Cattle in Campo Grande, state of Mato Grosso do Sul, Brazil, from July to September 2013. The evaluations were conducted on four consecutive days, from 8:00 a.m. to 5:00 p.m., local time (GMT -4:00), with 1 hour intervals, recording the microclimate parameters: air temperature (°C), black globe temperature (°C), wet bulb temperature (°C), relative humidity (%), and wind speed (m.s -1 ), for the subsequent calculation of the Temperature and Humidity Index, the Black Globe Temperature and Humidity Index, and the Radiant Thermal Load. The largest changes in microclimate parameters were found in the full sun, between 12:00 p.m. and 1:00 p.m., in less dense eucalyptus system, followed by the scattered native trees system, resulting in a maximum Temperature and Humidity Index of 81, Black Globe Temperature and Humidity Index of 88 and Radiant Thermal Load of 794 W m -2 . Therefore, it is observed that with the presence of trees in pastures were possible reductions of up to 3.7 % in Temperature and Humidity Index, 10.2 % in the Black Globe Temperature and Humidity Index, and 28.3 % of the Radiant Thermal Load in the shade. Thus, one can conclude that the presence of trees and their arrangement in the systems provide better microclimate conditions and animal thermal comfort in pastures.
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Stroh, Esther D.; Miller, Joel P.
2009-01-01
The Niobrara River Valley in north-central Nebraska supports scattered stands of paper birch (Betula papyrifera Marsh), a species more typical of boreal forests. These birch stands are considered to be relictual populations that have persisted since the end of the Wisconsin glaciation, when regional flora was more boreal in nature (Wright 1970, Kaul and others, 1988). Dieback of canopy-sized birch has been observed throughout the Niobrara Valley in recent years, although no onset dates are documented. The current dieback event probably started around or after the early 1980’s. The study objectives were to understand microclimatic conditions in birch stands relative to nearby weather stations and historic weather conditions, and to assess current health conditions of individual birch trees. Temperature was measured every half-hour from June 2005 through October 2007 in 12 birch stands and individual birch tree health was measured as expressed by percent living canopy in these and 13 additional stands in spring 2006 and 2007. Birch site microclimate was compared to data from a National Weather Service station in Valentine, Nebraska, and to an automated weather station at The Nature Conservancy Niobrara Valley Preserve 24 kilometers north of Johnstown, Nebraska. Historic weather data from the Valentine station and another National Weather Service Station at Ainsworth, Nebraska, were used to reconstruct minimum and maximum temperature at The Nature Conservancy and one microclimate monitoring station using Kalman filtering and smoothing algorithms. Birch stand microclimate differed from local weather stations as well as among stands. Birch health was associated with annual minimum temperature regimes; those stands whose annual daily minimum temperature regimes were most like The Nature Conservancy station contained smaller proportions of living trees. Frequency of freeze/thaw conditions capable of inducing rootlet injury and subsequent crown dieback significantly have
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Spatial and temporal variability of canopy microclimate in a Sierra Nevada riparian forest
T. Rambo; M. North
2008-01-01
Past riparian microclimate studies have measured changes horizontally from streams, but not vertically through the forest canopy. We recorded temperature and relative humidity for a year along a two-dimensional grid of 24 data-loggers arrayed up to 40 m height in four trees 2 - 30 m slope distance from a perennial second order stream in...
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Lee, Yejin; Hong, Kyunghi; Hong, Sung-Ae
2007-05-01
Garment fit and resultant air volume is a crucial factor in thermal insulation, and yet, it has been difficult to quantify the air volume of clothing microclimate and relate it to the thermal insulation value just using the information on the size of clothing pattern without actual 3D volume measurement in wear condition. As earlier methods for the computation of air volume in clothing microclimate, vacuum over suit and circumference model have been used. However, these methods have inevitable disadvantages in terms of cost or accuracy due to the limitations of measurement equipment. In this paper, the phase-shifting moiré topography was introduced as one of the 3D scanning tools to measure the air volume of clothing microclimate quantitatively. The purpose of this research is to adopt a non-contact image scanning technology, phase-shifting moiré topography, to ascertain relationship between air volume and insulation value of layered clothing systems in wear situations where the 2D fabric creates new conditions in 3D spaces. The insulation of vests over shirts as a layered clothing system was measured with a thermal manikin in the environmental condition of 20 degrees C, 65% RH and air velocity of 0.79 m/s. As the pattern size increased, the insulation of the clothing system was increased. But beyond a certain limit, the insulation started to decrease due to convection and ventilation, which is more apparent when only the vest was worn over the torso of manikin. The relationship between clothing air volume and insulation was difficult to predict with a single vest due to the extreme openings which induced active ventilation. But when the vest was worn over the shirt, the effects of thickness of the fabrics on insulation were less pronounced compared with that of air volume. In conclusion, phase-shifting moiré topography was one of the efficient and accurate ways of quantifying air volume and its distribution across the clothing microclimate. It is also noted
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Gefen, Amit
2011-08-01
In this study, a mathematical model is developed for analyzing the effects of the microclimate on skin tolerance to superficial pressure ulcers (SPUs). The modeling identified the following factors as such that decrease the tolerance of skin to SPUs: (i) increase in the skin temperature, (ii) increase in the ambient temperature, (iii) increase in the relative humidity, (iv) increase in the skin-support (or skin-clothing-support) contact pressures, and (v) decrease in permeabilities of the materials contacting the skin or being close to it, e.g. the covering sheet of the support and clothing. The modeling is consistent with relevant empirical findings and clinical observations documented in the literature, explains them from a basic science aspect, and can be further developed for design of interventions, safer patient clothing and supports that consider the optimization of microclimate factors. Copyright © 2010 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.
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Trailer microclimate and calf welfare during fall-run transportation of beef calves in Alberta.
Goldhawk, C; Janzen, E; González, L A; Crowe, T; Kastelic, J; Pajor, E; Schwartzkopf-Genswein, K S
2014-11-01
Twenty-four commercial loads of beef calves (BW 300 ± 52 kg, mean ± SD) were evaluated for associations among transportation factors, in-transit microclimate, and calf welfare. Transport factors evaluated included vehicle speed, space allowance, compartment within trailer, and transit duration. Calves were transported for 7 h 44 min ± 4 h 15 min, with space allowances ranging from 0.56 to 1.17 m(2)/animal. Compartment within trailer, space allowance, and vehicle speed did not affect the difference between compartment ceiling-level and ambient temperatures during a 30-min period of steady-state microclimate. During the steady-state period, a 1°C increase in ambient temperature above the mean of 5.6°C was associated with a 0.62°C decrease in the difference between ceiling-level and ambient temperature (P < 0.01). Ceiling-level temperature and humidity during the first 400 min of transport could be predicted by ambient conditions and vehicle speed (pseudo-r(2) of 0.91 and 0.82 for temperature and humidity ratio; P < 0.01). Events when animal-level temperature-humidity index (THI) was classified as above the "danger" level lasted for 10.2 ± 4.1 consecutive minutes. Ambient and ceiling-level THI values were not classified as above "danger" for 90.0 and 84.9% of animal-level events. Ambient and ceiling-level THI were 5.0 ± 2.1 and 4.7 ± 2.0° Flower than animal-level THI during periods of disagreement, respectively. The majority of calves arrived in good condition and biochemical indicators of calf welfare were within reference ranges for healthy cattle. Within the study population, high pre-transport cortisol and hematocrit were associated with elevated post-transport values (P < 0.01). A 1% increase in shrink during the weaning to loading interval (24 or 48 h) decreased transportation shrink by 0.26 ± 0.04% when average animal-level temperature was greater than 5°C and decreased transportation shrink by 0.11 ± 0.04% when average animal-level temperature was
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The effect of landscape complexity and microclimate on the thermal tolerance of a pest insect.
Alford, Lucy; Tougeron, Kévin; Pierre, Jean-Sébastien; Burel, Françoise; van Baaren, Joan
2017-03-21
Landscape changes are known to exacerbate the impacts of climate change. As such, understanding the combined effect of climate and landscape on agroecosystems is vital if we are to maintain the function of agroecosystems. This study aimed to elucidate the effects of agricultural landscape complexity on the microclimate and thermal tolerance of an aphid pest to better understand how landscape and climate may interact to affect the thermal tolerance of pest species within the context of global climate change. Meteorological data were measured at the landscape level, and cereal aphids (Sitobion avenae, Metopolophium dirhodum and Rhopalosiphum padi) sampled, from contrasting landscapes (simple and complex) in winter 2013/2014 and spring 2014 in cereal fields of Brittany, France. Aphids were returned to the laboratory and the effect of landscape of origin on aphid cold tolerance (as determined by CT min ) was investigated. Results revealed that local landscape complexity significantly affected microclimate, with simple homogenous landscapes being on average warmer, but with greater temperature variation. Landscape complexity was shown to impact aphid cold tolerance, with aphids from complex landscapes being more cold tolerant than those from simple landscapes in both winter and spring, but with differences among species. This study highlights that future changes to land use could have implications for the thermal tolerance and adaptability of insects. Furthermore, not all insect species respond in a similar way to microhabitat and microclimate, which could disrupt important predator-prey relationships and the ecosystem service they provide. © 2017 Institute of Zoology, Chinese Academy of Sciences.
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Stream-riparian areas represent a nexus of biodiversity, with disproportionate numbers of species tied to and interacting within this key habitat. New research in Pacific Northwest headwater forests, especially the characterization of microclimates and amphibian distributions, is...
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Diffusive and subdiffusive dynamics of indoor microclimate: a time series modeling.
Maciejewska, Monika; Szczurek, Andrzej; Sikora, Grzegorz; Wyłomańska, Agnieszka
2012-09-01
The indoor microclimate is an issue in modern society, where people spend about 90% of their time indoors. Temperature and relative humidity are commonly used for its evaluation. In this context, the two parameters are usually considered as behaving in the same manner, just inversely correlated. This opinion comes from observation of the deterministic components of temperature and humidity time series. We focus on the dynamics and the dependency structure of the time series of these parameters, without deterministic components. Here we apply the mean square displacement, the autoregressive integrated moving average (ARIMA), and the methodology for studying anomalous diffusion. The analyzed data originated from five monitoring locations inside a modern office building, covering a period of nearly one week. It was found that the temperature data exhibited a transition between diffusive and subdiffusive behavior, when the building occupancy pattern changed from the weekday to the weekend pattern. At the same time the relative humidity consistently showed diffusive character. Also the structures of the dependencies of the temperature and humidity data sets were different, as shown by the different structures of the ARIMA models which were found appropriate. In the space domain, the dynamics and dependency structure of the particular parameter were preserved. This work proposes an approach to describe the very complex conditions of indoor air and it contributes to the improvement of the representative character of microclimate monitoring.
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D.H. Olson; P.D. Anderson; C.A. Frissell; H.H. Welsh; D.F. Bradford
2007-01-01
New science insights are redefining stream riparian zones, particularly relative to headwaters, microclimate conditions, and fauna such as amphibians. We synthesize data on these topics, and propose management approaches to target sensitive biota at reach to landscape scales.
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Eben N. Broadbent; Angélica M. Almeyda Zambrano; Gregory P. Asner; Christopher B. Field; Brad E. Rosenheim; Ty Kennedy-Bowdoin; David E. Knapp; David Burke; Christian Giardina; Susan Cordell
2014-01-01
We develop and validate a high-resolution three-dimensional model of light and air temperature for a tropical forest interior in Hawaii along an elevation gradient varying greatly in structure but maintaining a consistent species composition. Our microclimate models integrate high-resolution airborne waveform light detection and ranging data (LiDAR) and hyperspectral...
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NASA Astrophysics Data System (ADS)
Shamshiri, Redmond Ramin; Jones, James W.; Thorp, Kelly R.; Ahmad, Desa; Man, Hasfalina Che; Taheri, Sima
2018-04-01
Greenhouse technology is a flexible solution for sustainable year-round cultivation of Tomato (Lycopersicon esculentum Mill), particularly in regions with adverse climate conditions or limited land and resources. Accurate knowledge about plant requirements at different growth stages, and under various light conditions, can contribute to the design of adaptive control strategies for a more cost-effective and competitive production. In this context, different scientific publications have recommended different values of microclimate parameters at different tomato growth stages. This paper provides a detailed summary of optimal, marginal and failure air and root-zone temperatures, relative humidity and vapour pressure deficit for successful greenhouse cultivation of tomato. Graphical representations of the membership function model to define the optimality degrees of these three parameters are included with a view to determining how close the greenhouse microclimate is to the optimal condition. Several production constraints have also been discussed to highlight the short and long-term effects of adverse microclimate conditions on the quality and yield of tomato, which are associated with interactions between suboptimal parameters, greenhouse environment and growth responses.
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Evaluation of Commercial Off-the-Shelf and Government Off-the-Shelf Microclimate Cooling Systems
2005-08-01
Appendix A - Request for Information (RFI) 23 Appendix B - Memorandum from Natick Soldier Center’s International Office 25 Appendix C - Cooling Power...Data Entry Forms 7 Figure 3. Evaporative Cooling Products 9 Figure 4. Passive Phase Change Product 10 Figure 5. Liquid Circulating...Microclimate Cooling System 13 Figure 6. Compressed Air Cooling Product 15 Figure 7. Vortex Tube 15 Figure 8. Active Phase
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Small Heat Shock Protein Responses Differ between Chaparral Shrubs from Contrasting Microclimates
Knight, Charles A.
2010-01-01
Smore » mall heat shock protein (sHsp) responses were studied for two evergreen perennial shrubs in the northern California chaparral; one common on warm, south-facing slopes ( Ceanothus cuneatus ), and the other on cooler, north-facing slopes ( Prunus ilicifolia ). mall Hsp expression was induced experimentally for field collected leaves. Leaf collections were made where the species co-occur. mall Hsp expression was quantified using two antibodies, one specific to a chloroplast 22 kD sHsp and another that detects a broad range of sHsps. Differences between chloroplast sHsp accumulation, which protects thermally labile proteins in PII, and the general sHsp response were examined. The species from the cooler microclimate, Prunus , had a lower induction temperature and accumulated greater levels of sHsps at low temperatures. Both Prunus and Ceanothus reached peak sHsp expression at 42 ∘ C . The species from the warmer microclimate, Ceanothus , had greater sHsp expression at higher temperatures. Chloroplast sHsp expression generally tracked sHsp expression in Ceanothus , but in Prunus general Hsps were elevated before chloroplast sHsps. Variation between species for sHsp expression (induction temperatures, accumulation levels, and the duration of expression) coupled with the costs of Hsp synthesis, may contribute to differences in the abundance and distribution of plants across environmental gradients.« less
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He, Yufei; D'Odorico, Paolo; De Wekker, Stephan F J
2015-06-01
Many arid and semi-arid landscapes around the world are affected by a shift from grassland to shrubland vegetation, presumably induced by climate warming, increasing atmospheric CO2 concentrations, and/or changing land use. This major change in vegetation cover is likely sustained by positive feedbacks with the physical environment. Recent research has focused on a feedback with microclimate, whereby cold intolerant shrubs increase the minimum nocturnal temperatures in their surroundings. Despite the rich literature on the impact of land cover change on local climate conditions, changes in microclimate resulting from shrub expansion into desert grasslands have remained poorly investigated. It is unclear to what extent such a feedback can affect the maximum extent of shrub expansion and the configuration of a stable encroachment front. Here, we focus on the case of the northern Chihuahuan desert, where creosotebush (Larrea tridentata) has been replacing grasslands over the past 100-150 years. We use a process-based coupled atmosphere-vegetation model to investigate the role of this feedback in sustaining shrub encroachment in the region. Simulations indicate that the feedback allows juvenile shrubs to establish in the grassland during average years and, once established, reduce their vulnerability to freeze-induced mortality by creating a warmer microclimate. Such a feedback is crucial in extreme cold winters as it may reduce shrub mortality. We identify the existence of a critical zone in the surroundings of the encroachment front, in which vegetation dynamics are bistable: in this zone, vegetation can be stable both as grassland and as shrubland. The existence of these alternative stable states explains why in most cases the shift from grass to shrub cover is found to be abrupt and often difficult to revert. © 2015 John Wiley & Sons Ltd.
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Invasion of Impatiens glandulifera affects terrestrial gastropods by altering microclimate
NASA Astrophysics Data System (ADS)
Ruckli, Regina; Rusterholz, Hans-Peter; Baur, Bruno
2013-02-01
Invasive species can have far-reaching impacts on ecosystems. Invasive plants may be able to change habitat structure and quality. We conducted a field experiment to examine whether the invasive plant Impatiens glandulifera affects native terrestrial gastropods. We also evaluated whether the invasive plant alters forest soil characteristics and microclimate which in turn may influence gastropod abundance. We sampled gastropods in plots installed in patches of I. glandulifera, in plots in which I. glandulifera was regularly removed by hand, and in control plots which were not yet colonized by the invasive plant. The three types of plots were equally distributed over three mixed deciduous forest areas that were slightly, moderately or heavily affected by a wind throw 11 years ago. A total of 33 gastropod species were recorded. Gastropod species richness was not affected by delayed effects of the wind throw, but it was significantly higher in invaded plots than in uninvaded plots. Similarly, gastropod abundance was higher in invaded plots than in the two types of control plots. Canonical correspondence analysis revealed marginally significant shifts of gastropod communities between the three types of plots and indicated that soil moisture, presence of I. glandulifera and cover of woody debris affected gastropod species composition. Field measurements showed that soil moisture was higher and daily soil temperature was more damped in patches of I. glandulifera than in the native ground vegetation. The changed microclimatic conditions may favour certain gastropod species. In particular, ubiquitous species and species with a high inundation tolerance increased in abundance in plots invaded by I. glandulifera. Our field experiment demonstrated that an invasive plant can indirectly affect native organisms by changing soil characteristics and microclimate.
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Microclimate and actual evapotranspiration in a humid coastal-plain environment
Dennehy, K.F.; McMahon, P.B.
1987-01-01
Continuous hourly measurements of twelve meteorologic variables recorded during 1983 and 1984 were used to examine the microclimate and actual evapotranspiration at a low-level radioactive-waste burial site near Barnwell, South Carolina. The study area is in the Atlantic Coastal Plain of southwestern South Carolina. Monthly, daily, and hourly trends in net radiation, incoming and reflected short-wave radiation, incoming and emitted long-wave radiation, soil-heat flux, dry- and wet-bulb temperatures, soil temperatures, wind direction and speed, and precipitation were used to characterize the microclimate. Average daily air temperatures ranged from -9 to 32?? Celsius during the period of study. Net radiation varied from about -27 to 251 watts m-2 and was dominated by incoming short-wave radiation throughout the year. The peak net radiation during a summer day generally occurred 2-3h before the peak vapor pressure deficit. In the winter, these peaks occurred at about the same time of day. Monthly precipitation varied from 15 to 241 mm. The Bowen ratio method was used to estimate hourly evapotranspiration, which was summed to also give daily and monthly evapotranspiration. Actual evapotranspiration varied from 0.0 to 0.7 mm h-1, 0.8-5 mm d-1, and 20-140 mm month-1 during 1983 and 1984. The maximum rate of evapotranspiration generally occurred at the same time of day as maximum net radiation, suggesting net radiation was the main driving force for evapotranspiration. Precipitation exceeded evapotranspiration during 14 months of the 2yr study period. Late fall, winter, and early spring contained the majority of these months. The maximum excess precipitation was 115 mm in February 1983. ?? 1987.
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Siyan Ma; Amy Concilio; Brian Oakley; Malcolm North; Jiquan Chen
2010-01-01
In the western United States, mechanical thinning and prescribed fire are common forest management practices aimed at reducing potential wildfire severity and restoring historic forest structure, yet their effects on forestmicroclimate conditions are not well understood. We collected microclimate data between 1998 and 2003 in amixed-coniferforest in California's...
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Release of Oregon white oak from overtopping Douglas-fir: effects on soil water and microclimate.
W.D. Devine; C.A. Harrington
2007-01-01
Many former Oregon white oak woodland and savanna stands in the coastal Pacific Northwest have been invaded and subsequently overtopped by Douglas-fir during the past century. We examined soil water and microclimate conditions near overtopped oak trees and near oak trees that had been released from Douglas-fir. In each of the three study years, volumetric soil water...
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Reeves, Ian; Emery, R J Neil
2007-11-01
Seasonal patterns of cytokinins (CKs) and microclimate were examined in the upper, middle and lower canopy layers of mature Acer saccharum Marsh. (sugar maple) trees to elucidate the potential role of CKs in the mediation of gas exchange. The upper canopy showed a distinctly dissimilar microclimate from the middle and lower canopy layers with higher photosynthetically active radiation and wind speed, but showed no corresponding differences in transpiration (E) or stomatal conductance (g(s)). Although E and g(s) tended to be higher in the upper canopy than in the middle and lower canopies, the differences were not significant, indicating regulation beyond the passive response to changes in microclimate. The upper canopy accumulated significantly higher concentrations of CKs, predominantly as ribosides, and all canopy layers showed distinct seasonal patterns in CK profiles. Multiple regression models showed significant relationships between both g(s) and E and foliar CK concentration, although these relationships varied among canopy layers. The relationships were strongest in the middle and lower canopy layers where there was less fluctuation in leaf water status and less variability in abiotic variables. The relationships between gas exchange parameters and leaf CK concentration began to decouple near the end of the growing season as foliar phytohormone concentrations changed with the approach of dormancy.
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NASA Astrophysics Data System (ADS)
Coughlan, Neil E.; Kelly, Tom C.; Davenport, John; Jansen, Marcel A. K.
2015-05-01
Birds as carriers of propagules are major agents in the dispersal of plants, animals, fungi and microbes. However, there is a lack of empirical data in relation to bird-mediated, epizoochorous dispersal. The microclimate found within the plumage likely plays a pivotal role in survival during flight conditions. To investigate the potential of epizoochory, we have analysed the microclimatic conditions within the plumage of mallard ducks (Anas platyrhynchos). Under similar ambient conditions of humidity and temperature, a sample of mallards showed a consistent microclimatic regime with variation across the body surface. The highest (mean) temperature and specific humidity occurred between feathers of the postpatagium. The lowest humidity was found between feathers of the centre back and the lowest temperature in the crissum. Observed differences in plumage depth and density, and distance from the skin, are all likely to be determining factors of microclimate condition. Specific humidity found within the plumage was on average 1.8-3.5 times greater than ambient specific humidity. Thus, the plumage can supply a microclimate buffered from that of the exterior environment. Extrapolating survival data for Lemna minor desiccation at various temperature and humidity levels to the measured plumage microclimatic conditions of living birds, survival for up to 6 h can be anticipated, especially in crissum, crural and breast plumage. The results are discussed in the context of potential long distance epizoochorous dispersal by A. platyrhynchos and similar species.
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W.B. Sutton; Y. Wang; C.J. Schweitzer; D.A. Steen
2014-01-01
Understanding the impacts of disturbances in forest ecosystems is essential for long-term biodiversity conservation. Many studies have evaluated wildlife responses to various disturbances but most generally do not use changes in microclimate features or crohabitat structure to explain these responses. We examined lizard responses to two common forest management...
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Heat removal using microclimate foot cooling: a thermal foot manikin study.
Castellani, John W; Demes, Robert; Endrusick, Thomas L; Cheuvront, Samuel N; Montain, Scott J
2014-04-01
It has been proposed that microclimate cooling systems exploit the peripheral extremities because of more efficient heat transfer. The purpose of this study was to quantify, using a patented microclimate cooling technique, the heat transfer from the plantar surface of the foot for comparison to other commonly cooled body regions. A military boot was fitted with an insole embedded with a coiled, 1.27 m length of hollow tubing terminating in inlet and outlet valves. A thermal foot manikin with a surface temperature of 34 degrees C was placed in the boot and the valves were connected to a system that circulated water through the insole at a temperature of 20 degrees C and flow rate of 120 ml x min(-1). The manikin foot served as a constant heat source to determine heat transfer provided by the insole. Testing was done with the foot model dry and sweating at a rate of 500 ml x h(- 1) x m(-2). Climatic chamber conditions were 30 degrees C with 30% RH. Heat loss was approximately 4.1 +/- 0.1 and approximately 7.7 +/- 0.3 W from the dry and sweating foot models, respectively. On a relative scale, the heat loss was 3.0 W and 5.5 W per 1% (unit) body surface area, respectively, for the dry and sweating conditions. The relative heat loss afforded by plantar foot cooling was similar compared to other body regions, but the absolute amount of heat removal is unlikely to make an impact on whole body heat balance.
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Rebaudo, François; Faye, Emile; Dangles, Olivier
2016-01-01
A large body of literature has recently recognized the role of microclimates in controlling the physiology and ecology of species, yet the relevance of fine-scale climatic data for modeling species performance and distribution remains a matter of debate. Using a 6-year monitoring of three potato moth species, major crop pests in the tropical Andes, we asked whether the spatiotemporal resolution of temperature data affect the predictions of models of moth performance and distribution. For this, we used three different climatic data sets: (i) the WorldClim dataset (global dataset), (ii) air temperature recorded using data loggers (weather station dataset), and (iii) air crop canopy temperature (microclimate dataset). We developed a statistical procedure to calibrate all datasets to monthly and yearly variation in temperatures, while keeping both spatial and temporal variances (air monthly temperature at 1 km² for the WorldClim dataset, air hourly temperature for the weather station, and air minute temperature over 250 m radius disks for the microclimate dataset). Then, we computed pest performances based on these three datasets. Results for temperature ranging from 9 to 11°C revealed discrepancies in the simulation outputs in both survival and development rates depending on the spatiotemporal resolution of the temperature dataset. Temperature and simulated pest performances were then combined into multiple linear regression models to compare predicted vs. field data. We used an additional set of study sites to test the ability of the results of our model to be extrapolated over larger scales. Results showed that the model implemented with microclimatic data best predicted observed pest abundances for our study sites, but was less accurate than the global dataset model when performed at larger scales. Our simulations therefore stress the importance to consider different temperature datasets depending on the issue to be solved in order to accurately predict species
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Rebaudo, François; Faye, Emile; Dangles, Olivier
2016-01-01
A large body of literature has recently recognized the role of microclimates in controlling the physiology and ecology of species, yet the relevance of fine-scale climatic data for modeling species performance and distribution remains a matter of debate. Using a 6-year monitoring of three potato moth species, major crop pests in the tropical Andes, we asked whether the spatiotemporal resolution of temperature data affect the predictions of models of moth performance and distribution. For this, we used three different climatic data sets: (i) the WorldClim dataset (global dataset), (ii) air temperature recorded using data loggers (weather station dataset), and (iii) air crop canopy temperature (microclimate dataset). We developed a statistical procedure to calibrate all datasets to monthly and yearly variation in temperatures, while keeping both spatial and temporal variances (air monthly temperature at 1 km² for the WorldClim dataset, air hourly temperature for the weather station, and air minute temperature over 250 m radius disks for the microclimate dataset). Then, we computed pest performances based on these three datasets. Results for temperature ranging from 9 to 11°C revealed discrepancies in the simulation outputs in both survival and development rates depending on the spatiotemporal resolution of the temperature dataset. Temperature and simulated pest performances were then combined into multiple linear regression models to compare predicted vs. field data. We used an additional set of study sites to test the ability of the results of our model to be extrapolated over larger scales. Results showed that the model implemented with microclimatic data best predicted observed pest abundances for our study sites, but was less accurate than the global dataset model when performed at larger scales. Our simulations therefore stress the importance to consider different temperature datasets depending on the issue to be solved in order to accurately predict species
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Regional climate modulates the canopy mosaic of favourable and risky microclimates for insects.
Pincebourde, Sylvain; Sinoquet, Herve; Combes, Didier; Casas, Jerome
2007-05-01
1. One major gap in our ability to predict the impacts of climate change is a quantitative analysis of temperatures experienced by organisms under natural conditions. We developed a framework to describe and quantify the impacts of local climate on the mosaic of microclimates and physiological states of insects within tree canopies. This approach was applied to a leaf mining moth feeding on apple leaf tissues. 2. Canopy geometry was explicitly considered by mapping the 3D position and orientation of more than 26 000 leaves in an apple tree. Four published models for canopy radiation interception, energy budget of leaves and mines, body temperature and developmental rate of the leaf miner were integrated. Model predictions were compared with actual microclimate temperatures. The biophysical model accurately predicted temperature within mines at different positions within the tree crown. 3. Field temperature measurements indicated that leaf and mine temperature patterns differ according to the regional climatic conditions (cloudy or sunny) and depending on their location within the canopy. Mines in the sun can be warmer than those in the shade by several degrees and the heterogeneity of mine temperature was incremented by 120%, compared with that of leaf temperature. 4. The integrated model was used to explore the impact of both warm and exceptionally hot climatic conditions recorded during a heat wave on the microclimate heterogeneity at canopy scale. During warm conditions, larvae in sunlight-exposed mines experienced nearly optimal growth conditions compared with those within shaded mines. The developmental rate was increased by almost 50% in the sunny microhabitat compared with the shaded location. Larvae, however, experienced optimal temperatures for their development inside shaded mines during extreme climatic conditions, whereas larvae in exposed mines were overheating, leading to major risks of mortality. 5. Tree canopies act as both magnifiers and reducers
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NASA Astrophysics Data System (ADS)
Hannah, David M.; Gurnell, Angela M.; McGregor, Glenn R.
2000-06-01
Climatic processes, operating at a range of scales, drive energy fluxes at the glacier surface which control meltwater generation and ultimately runoff. Nevertheless, to date, most glacier microclimate research has been both temporally (short-term) and spatially (single station) restricted. This paper addresses this knowledge gap by reporting on a detailed, empirical study which characterizes spatio-temporal variations in and linkages between glacier microclimate, surface energy and mass exchanges within a small glacierized cirque (Taillon Glacier, French Pyrénées) over two melt seasons. Data collected at five automatic weather stations (AWSs) and over ablation stake networks suggest that topoclimates, altitude and transient snowline position primarily determine the distribution of glacier energy receipt and, in turn, snow- and ice-melt patterns. Generally net radiation is the dominant energy source, followed by sensible heat, while latent heat is an energy sink. However, the magnitude and partitioning of energy balance terms, and consequently ablation, vary across the glacier both seasonally and with prevailing weather conditions. Importantly, this paper demonstrates that such monitoring programmes are required to truly represent and provide a sound basis for modelling glacier energy and mass-balances in both space and time.
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Johns, R C; Boone, J; Leggo, J J; Smith, S; Carleton, D; Quiring, D T
2012-06-01
Herbivorous insects are often exposed to broad temporal and spatial variations in microclimate conditions within their host plants and have adapted a variety of behaviors, such as avoidance or basking, to either offset or benefit from such variation. Field experiments were carried out to investigate the influence of daily and intratree variations in microclimate on the behaviors (feeding, resting, dispersal, and hiding) and associated performance of late-instar larvae of the yellowheaded spruce sawfly, Pikonema alaskensis (Rohwer) (Hymenoptera: Tenthredinidae) within crowns of 1.25-1.5 m tall black spruce (Picea mariana [Miller] Britton Sterns Poggenburg); late instars feed on developing shoots of young spruce and are often exposed to microclimatic extremes with unknown effects on performance. Larvae fed diurnally from just after dawn (0800 h) until dusk (2000 h) and rested throughout the night, with brief periods of dispersal occurring in the morning and evening. Neither larval behavior nor abiotic conditions differed significantly between the upper and lower crowns of trees. Temperature, humidity, and solar insolation all explained >90% of variation in feeding; however, sunrise and sunset were the most likely cues influencing diurnal behavior. Most larvae (94%) fed on the bottom, shaded side of shoots, and field experiments indicated that this behavior is adaptive with respect to microclimate, probably reducing hygrothermal stress. Thus, behavioral adaptations by P. alaskensis to daily and within-shoot microclimatic variation may reduce the risk of hygrothermal stress during dispersal or feeding, while still allowing larvae to feed on the preferred and highly nutritious upper crown foliage of young spruce.
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Zeevi, Tal; Levy, Ayelet; Brauner, Neima; Gefen, Amit
2018-06-01
Scientific evidence regarding microclimate and its effects on the risk of pressure ulcers (PU) remains sparse. It is known that elevated skin temperatures and moisture may affect metabolic demand as well as the mechanical behaviour of the tissue. In this study, we incorporated these microclimate factors into a novel, 3-dimensional multi-physics coupled model of the human buttocks, which simultaneously determines the biothermal and biomechanical behaviours of the buttocks in supine lying on different support surfaces. We compared 3 simulated thermally controlled mattresses with 2 reference foam mattresses. A tissue damage score was numerically calculated in a relevant volume of the model, and the cooling effect of each 1°C decrease of tissue temperature was deduced. Damage scores of tissues were substantially lower for the non-foam mattresses compared with the foams. The percentage tissue volume at risk within the volume of interest was found to grow exponentially as the average tissue temperature increased. The resultant average sacral skin temperature was concluded to be a good predictor for an increased risk of PU/injuries. Each 1°C increase contributes approximately 14 times as much to the risk with respect to an increase of 1 mmHg of pressure. These findings highlight the advantages of using thermally controlled support surfaces as well as the need to further assess the potential damage that may be caused by uncontrolled microclimate conditions on inadequate support surfaces in at-risk patients. © 2017 Medicalhelplines.com Inc and John Wiley & Sons Ltd.
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Evaluation of three commercial microclimate cooling systems
NASA Astrophysics Data System (ADS)
Cadarette, Bruce S.; Decristofano, Barry S.; Speckman, Karen N.; Sawka, Michael N.
1988-11-01
Three commercially available microclimate cooling systems were evaluated for their ability to reduce heat stress in men exercising in a hot environment while wearing high insulative, low permeability clothing. The cooling systems were: (1) ILC Dover Model 19 Coolvest (ILC) (2) LSSI Coolhead(LSSI), and (3) Thermacor Cooling vest (THERM). Endurance Time (ET), Heart Rate (HR), rectal temperature (Tre), mean skin temperature (TSK), Sweating Rate (SR), Rated Perceived Exertion (RPE) and Thermal Sensation (TS) were measured. The subjects self-terminated on all LSSI tests because of headaches. Statistical analyses were performed on data collected at 60 minutes to have values on all subjects. There were no differences in HR, Tre, SR or TS values among the cooling vests. The subjects' TSK was lower (P less than 0.05) for the LSSI than THERM: and RPE values were higher (P less than 0.05) for LSSI than the other two vests. These data suggest an improved physiological response to exercise heat stress with all three commercial systems with the greatest benefit in performance time provided by the ILC cooling system.
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Di, Sun; Guan, De-xin; Yuan, Feng-hui; Wang, An-zhi; Wu, Jia-bing
2010-11-01
By using Granier's thermal dissipation probe, the sap flow velocity of the poplars in agroforestry system in west Liaoning was continuously measured, and the microclimate factors were measured synchronously. Dislocation contrast method was applied to analyze the sap flow velocity and corresponding air temperature, air humidity, net radiation, and vapor pressure deficit to discuss the time lag effect between poplar' s sap flow velocity and microclimate factors on sunny days. It was found that the poplar's sap flow velocity advanced of air temperature, air humidity, and vapor pressure deficit, and lagged behind net radiation. The sap flow velocity in June, July, August, and September was advanced of 70, 30, 50, and 90 min to air temperature, of 80, 30, 40, and 90 min to air humidity, and of 90, 50, 70, and 120 min to vapor pressure deficit, but lagged behind 10, 10, 40, and 40 min to net radiation, respectively. The time lag time of net radiation was shorter than that of air temperature, air humidity, and vapor pressure. The regression analysis showed that in the cases the time lag effect was contained and not, the determination coefficients between comprehensive microclimate factor and poplar's sap flow velocity were 0.903 and 0.855, respectively, indicating that when the time lag effect was contained, the determination coefficient was ascended by 2.04%, and thus, the simulation accuracy of poplar's sap flow velocity was improved.
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NASA Astrophysics Data System (ADS)
Rajewski, Daniel A.; Takle, Eugene S.; Prueger, John H.; Doorenbos, Russell K.
2016-11-01
Recent wind farm studies have revealed elevated nighttime surface temperatures but have not validated physical mechanisms that create the observed effects. We report measurements of concurrent differences in surface wind speed, temperature, fluxes, and turbulence upwind and downwind of two turbine lines at the windward edge of a utility-scale wind farm. On the basis of these measurements, we offer a conceptual model based on physical mechanisms of how wind farms affect their own microclimate. Periods of documented curtailment and zero-power production of the wind farm offer useful opportunities to rigorously evaluate the microclimate impact of both stationary and operating turbines. During an 80 min nighttime wind farm curtailment, we measured abrupt and large changes in turbulent fluxes of momentum and heat leeward of the turbines. At night, wind speed decreases in the near wake when turbines are off but abruptly increases when turbine operation is resumed. Our measurements are compared with Moderate Resolution Imaging Spectroradiometer Terra and Aqua satellite measurements reporting wind farms to have higher nighttime surface temperatures. We demonstrate that turbine wakes modify surface fluxes continuously through the night, with similar magnitudes during the Terra and Aqua transit periods. Cooling occurs in the near wake and warming in the far wake when turbines are on, but cooling is negligible when turbines are off. Wind speed and surface stratification have a regulating effect of enhancing or decreasing the impact on surface microclimate due to turbine wake effects.
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Paul E. Hennon; David V. D' Amore; Dustin T. Witter; Melinda B. Lamb
2010-01-01
Site factors predispose yellow-cedar (Chamaecyparis nootkatensis D. Don (Spach)) to a widespread climate-induced mortality in southeast Alaska. We investigated the influence of canopy cover and snow on microclimate at two small watersheds across a range of declining yellow-cedar stands on Baranof and Chichagof Islands in southeast Alaska. Two...
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USDA-ARS?s Scientific Manuscript database
Soil and irrigation management have been used to optimize crop production. However,their effects on microclimate, development, and controls of potato diseases have not been adequately quantified. The effects of soil, crop, and water management on development of potato early blight and late blight we...
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LOUNIBOS, L. P.; O'MEARA, G. F.; JULIANO, S. A.; NISHIMURA, N.; ESCHER, R. L.; REISKIND, M. H.; CUTWA, M.; GREENE, K.
2010-01-01
Within 2 yr of the arrival of the invasive container mosquito Aedes albopictus (Skuse), the previously dominant invasive mosquito Aedes aegypti (L.) disappeared from many Florida cemeteries. At some cemeteries, however, Ae. aegypti populations seem stable despite Ae. albopictus invasion. We sought to understand this variation in the outcome (exclusion, coexistence) of this invasion, given that previous experiments show that Ae. albopictus is the superior larval competitor. We tested experimentally the hypothesis that climate-dependent egg survivorship differs between exclusion and coexistence cemeteries and that differences in invasion outcome are associated with microclimate. Viability of eggs oviposited in the laboratory and suspended in vases at six cemeteries was significantly greater for Ae. aegypti than for Ae. albopictus, and greater in 2001 than in 2006. Cemeteries differed significantly in egg survivorship of Ae. albopictus, but not of Ae. aegypti, which is consistent with the hypothesis that Ae. albopictus suffers site-specific, climate-driven egg mortality that mitigates the competitive superiority of larval Ae. albopictus. Principal component (PC) analysis of microclimate records from vases during the experiments yielded three PCs accounting for >96% of the variance in both years of experiments. Multivariate analysis of variance of the three PCs revealed significant microclimate differences among the six cemeteries and between exclusion versus coexistence cemeteries. Stepwise logistic regression of egg survivorship versus microclimate PCs yielded significant fits for both species, and twice as much variance explained for Ae. albopictus as for Ae. aegypti in both years. Higher mortalities in 2006 were associated with high average daily maximum temperatures in vases, with lethal thresholds for both species at ≈40°C. From 1990 to 2007, vase occupancy by Ae. albopictus increased and that by Ae. aegypti decreased, with increasing seasonal precipitation at
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Impacts of day versus night warming on soil microclimate: results from a semiarid temperate steppe.
Xia, Jianyang; Chen, Shiping; Wan, Shiqiang
2010-06-15
One feature of climate warming is that increases in daily minimum temperature are greater than those in daily maximum temperature. Changes in soil microclimate in response to the asymmetrically diurnal warming scenarios can help to explain responses of ecosystem processes. In the present study, we examined the impacts of day, night, and continuous warming on soil microclimate in a temperate steppe in northern China. Our results showed that day, night, and continuous warming (approximately 13Wm(-2) with constant power mode) significantly increased daily mean soil temperature at 10cm depth by 0.71, 0.78, and 1.71 degrees C, respectively. Night warming caused greater increases in nighttime mean and daily minimum soil temperatures (0.74 and 0.99 degrees C) than day warming did (0.60 and 0.66 degrees C). However, there were no differences in the increases in daytime mean and daily maximum soil temperature between day (0.81 and 1.13 degrees C) and night (0.81 and 1.10 degrees C) warming. The differential effects of day and night warming on soil temperature varied with environmental factors, including photosynthetic active radiation, vapor-pressure deficit, and wind speed. When compared with the effect of continuous warming on soil temperature, the summed effects of day and night warming were lower during daytime, but greater at night, thus leading to equality at daily scale. Mean volumetric soil moisture at the depth of 0-40cm significantly decreased under continuous warming in both 2006 (1.44 V/V%) and 2007 (0.76 V/V%). Day warming significantly reduced volumetric soil moisture only in 2006, whereas night warming had no effect on volumetric soil moisture in both 2006 and 2007. Given the different diurnal warming patterns and variability of environmental factors among ecosystems, these results highlight the importance of incorporating the differential impacts of day and night warming on soil microclimate into the predictions of terrestrial ecosystem responses to climate
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The influence of mosquito resting behaviour and associated microclimate for malaria risk.
Paaijmans, Krijn P; Thomas, Matthew B
2011-07-07
The majority of the mosquito and parasite life-history traits that combine to determine malaria transmission intensity are temperature sensitive. In most cases, the process-based models used to estimate malaria risk and inform control and prevention strategies utilize measures of mean outdoor temperature. Evidence suggests, however, that certain malaria vectors can spend large parts of their adult life resting indoors. If significant proportions of mosquitoes are resting indoors and indoor conditions differ markedly from ambient conditions, simple use of outdoor temperatures will not provide reliable estimates of malaria transmission intensity. To date, few studies have quantified the differential effects of indoor vs outdoor temperatures explicitly, reflecting a lack of proper understanding of mosquito resting behaviour and associated microclimate. Published records from 8 village sites in East Africa revealed temperatures to be warmer indoors than outdoors and to generally show less daily variation. Exploring the effects of these temperatures on malaria parasite development rate suggested indoor-resting mosquitoes could transmit malaria between 0.3 and 22.5 days earlier than outdoor-resting mosquitoes. These differences translate to increases in transmission risk ranging from 5 to approaching 3,000%, relative to predictions based on outdoor temperatures. The pattern appears robust for low- and highland areas, with differences increasing with altitude. Differences in indoor vs outdoor environments lead to large differences in the limits and the intensity of malaria transmission. This finding highlights a need to better understand mosquito resting behaviour and the associated microclimate, and to broaden assessments of transmission ecology and risk to consider the potentially important role of endophily.
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Andrew D. George; Frank R. Thompson; John. Faaborg
2015-01-01
A spatial mismatch exists between regional climate models and conditions experienced by individual organisms. We demonstrate an approach to downscaling air temperatures for site-level studies using airborne LiDAR data and remote microclimate loggers. In 2012-2013, we established a temperature logger network in the forested region of central Missouri, USA, and obtained...
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Abd Latif, Zulkiflee; Blackburn, George Alan
2010-03-01
The creation of gaps can strongly influence forest regeneration and habitat diversity within forest ecosystems. However, the precise characteristics of such effects depend, to a large extent, upon the way in which gaps modify microclimate and soil water content. Hence, the aim of this study was to understand the effects of gap creation and variations in gap size on forest microclimate and soil water content. The study site, in North West England, was a mixed temperate broadleaved deciduous forest dominated by mature sessile oak (Quercus petraea), beech (Fagus sylvatica) and ash (Fraxinus excelsior) with some representatives of sycamore (Acer pseudoplatanus). Solar radiation (I), air temperature (T(A)), soil temperature (T(S)), relative humidity (h), wind speed (v) and soil water content (Psi) were measured at four natural treefall gaps created after a severe storm in 2006 and adjacent sub-canopy sites. I, T(A), T(S), and Psi increased significantly with gap size; h was consistently lower in gaps than the sub-canopy but did not vary with gap size, while the variability of v could not be explained by the presence or size of gaps. There were systematic diurnal patterns in all microclimate variables in response to gaps, but no such patterns existed for Psi. These results further our understanding of the abiotic and consequent biotic responses to gaps in broadleaved deciduous forests created by natural treefalls, and provide a useful basis for evaluating the implications of forest management practices.
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Comparison of microclimate in various land-use systems in Sumatra, Indonesia
NASA Astrophysics Data System (ADS)
Shekhar Badu, Chandra; Meijide, Ana; Gunawan, Dodo; Knohl, Alexander
2017-04-01
Deforestation and land-use changes are ongoing problems for rain forests in Indonesia. The conversion of forests to monocultures of rubber and oil palm plantations reduces not only biodiversity and carbon pools but also affects canopy structure, which is an important determinant of microclimate. There is, however, a lack of quantitative information characterizing the effect of land transformation on microclimate with a systematic experimental design. Here, we report observations microclimatic conditions (air temperature, relative humidity, soil moisture and soil temperature) on a daily, weekly and seasonal basis across four land-use systems (rain forest, jungle rubber, rubber plantation, oil palm plantation) in two near-by landscapes. The data set covers a period of approximately three years from April 2013 to March 2016 and includes one of the strongest El Nino-Southern Oscillation (ENSO) of the last decades. Mean air temperature, soil temperature, relative humidity, and vapour pressure deficit differed significantly between the four land-use systems whereas the mean soil moisture differed significantly between two landscapes. Air temperature, vapour pressure deficit and soil temperature were highest in oil palm and rubber plantations whereas lowest in forest and jungle rubber. Canopy openness was the most dominant control of microclimatic differences across the land-use systems. During the ENSO 2015, a significant increase in mean air temperature, soil temperature and vapour pressure deficit but a decrease in relative air humidity and soil moisture in all four land-use systems was found. The relative effect of ENSO was highest in forest and jungle rubber compared to rubber and oil palm plantations. In conclusion, conversion of forest to rubber and oil palm plantations has led to substantially warmer and drier microclimatic conditions than before.
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Impact Assessments and Projections in Microclimates: Working with End-Users
NASA Astrophysics Data System (ADS)
Outten, S.; Wolf, T.
2015-12-01
Local impacts of meteorological events are often shaped by the microclimates in which they occur and only by including understanding of these microclimates can robust assessments and projections of such events be made. However, co-production of knowledge with end users is also required in order to make the assessments useful for decision makers and for society as a whole. This work presents two studies working with end users around the European city of Bergen, Norway. The first study is on extreme winds assessment for larger-scale construction. While such an assessment is usually based on historical observations when the climate was more stationary, under a changing climate, infrastructure built to last for the next fifty years or more may experience events not seen in the observational period. The case study is presented for the newly completed Hardanger Bridge in Norway and demonstrates a novel method for incorporating estimates of future changes in extreme winds into the design process (figure 1). Given the close collaboration with the engineers involved in the bridge's construction, the method was tailored to fit with existing practices and standards. The second study focuses on air pollution events within the city that are favoured by persistent wintertime temperature inversions in the narrow Bergen valley. Using a temperature profile radiometer, these temperature inversions have been characterized and related to the local circulation in- and above the valley. There has been the assumption that the many large ships in Bergen harbour had a major contribution to high pollution events within the city. Results from this study however indicate that temperature inversions are mostly connected to down-valley winds. These should remove the ship-emissions from the city, giving the ships a much smaller impact on high air pollution events than previously assumed, something that is under further evaluation and of high interest for the local harbour authority. Figure 1
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USDA-ARS?s Scientific Manuscript database
We have developed and field-validated an annual inventory model for California landfill CH4 emissions that incorporates both site-specific soil properties and soil microclimate modeling coupled to 0.5o scale global climatic models. Based on 1-D diffusion, CALMIM (California Landfill Methane Inventor...
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The influence of mosquito resting behaviour and associated microclimate for malaria risk
2011-01-01
Background The majority of the mosquito and parasite life-history traits that combine to determine malaria transmission intensity are temperature sensitive. In most cases, the process-based models used to estimate malaria risk and inform control and prevention strategies utilize measures of mean outdoor temperature. Evidence suggests, however, that certain malaria vectors can spend large parts of their adult life resting indoors. Presentation of hypothesis If significant proportions of mosquitoes are resting indoors and indoor conditions differ markedly from ambient conditions, simple use of outdoor temperatures will not provide reliable estimates of malaria transmission intensity. To date, few studies have quantified the differential effects of indoor vs outdoor temperatures explicitly, reflecting a lack of proper understanding of mosquito resting behaviour and associated microclimate. Testing the hypothesis Published records from 8 village sites in East Africa revealed temperatures to be warmer indoors than outdoors and to generally show less daily variation. Exploring the effects of these temperatures on malaria parasite development rate suggested indoor-resting mosquitoes could transmit malaria between 0.3 and 22.5 days earlier than outdoor-resting mosquitoes. These differences translate to increases in transmission risk ranging from 5 to approaching 3,000%, relative to predictions based on outdoor temperatures. The pattern appears robust for low- and highland areas, with differences increasing with altitude. Implications of the hypothesis Differences in indoor vs outdoor environments lead to large differences in the limits and the intensity of malaria transmission. This finding highlights a need to better understand mosquito resting behaviour and the associated microclimate, and to broaden assessments of transmission ecology and risk to consider the potentially important role of endophily. PMID:21736735
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Ha, M; Tokura, H; Tanaka, Y; Holmér, I
1996-01-01
Thermophysiological responses and clothing microclimate under the influences of different underwear materials were compared during walking and recovery in the cold. Two kinds of underwear were used: two layers of cotton underwear with two-piece long-sleeved shirt and long-legged trousers (C), two layers of polypropylene underwear with two-piece long-sleeved shirt and long-legged trousers (P). In addition, the subject put on a two-piece ski suit of 100% polyester including 100% polyester padding. Seven adult females served as subjects in this study. The test was done in a climatic chamber at an ambient air temperature of 2 degrees C, a relative humidity of 65% and an air velocity of 0.14 m.s-1. The subject walked on a motor-driven treadmill with a 6 km/h speed for 30 min followed by 60 min recovery. Rectal temperature, skin temperatures, clothing microclimate (temperature, humidity), metabolic heat production and heart rate were measured. Furthermore, subjective ratings on thermal sensation, sweating/shivering sensation, clothing wettedness sensation and skin wettedness sensation for whole body were asked. The major findings are summarized as follows: 1) Mean skin temperature was not significantly different during walking, but it was significantly higher in P than in C during the recovery. 2) The absolute humidity of innermost layer and outermost layer were not significantly different during walking, but it was significantly higher in P than in C during the recovery. 3) Clothing microclimate temperature of innermost was not significantly different during the first half of walking, but it was significantly higher in C than in P during the second half of walking and significantly lower in C than in P during the recovery. Clothing microclimate temperature of outermost was not significantly different during walking, but it was significantly higher in P than in C during the recovery. 4) Metabolic heat production for the last 10 min during recovery tended to be higher in
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NASA Astrophysics Data System (ADS)
Ozbay, G.; Sriharan, S.; Fan, C.; Adolf, J.
2015-12-01
Undergraduate student experiential learning activities focused on microclimates of Hawai'i Island, Hawai'i. Six students from Virginia State University, three students from Delaware State University and faculty advisors were hosted by the University of Hawai'i at Hilo (UHH) Department of Marine Science. This partnership provided integrated, cohesive, and innovative education and research capabilities to minority students on climate change science. Activities included a summer course, instrumentation training, field and laboratory research training, sampling, data collection, logging, analysis, interpretation, report preparation, and research presentation. Most training activities used samples collected during students' field sampling in Hilo Bay. Water quality and phytoplankton data were collected along a 220 degree line transect from the mouth of the Wailuku River to the pelagic zone outside of Hilo Bay into the Pacific Ocean to a distance of 15.5 km. Water clarity, turbidity, chlorophyll, physical water quality parameters, and atmospheric CO2 levels were measured along the transect. Phytoplankton samples were collected for analysis by Scanning Electron Microscopy and Flow Cytometry. Data showed the extent of anthropogenic activity on water quality, with implications for food web dynamics. In addition, atmospheric CO2 concentration, island vegetation, and GPS points were recorded throughout the island of Hawai'i to investigate how variations in microclimate, elevation, and land development affect the amount of CO2 in the atmosphere, vegetation, and water quality. Water quality results at locations near rivers were completely different from other study sites, requiring students' critical thinking skills to find possible reasons for the difference. Our data show a correlation between population density and CO2 concentrations. Anthropogenic activities affecting CO2 and ocean conditions in Hawaiian microclimates can potentially have deleterious effects on the life
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Afanas'eva, R F; Prokopenko, L V; Kiladze, N A; Konstantinov, E I
2009-01-01
The authors demonstrated differences in heat state among workers exposed to heating microclimate during cold and warm seasons. Same external thermal load in cold season induces more humidity loss, lower weighted average skin temperature, higher pulse rate, increased systolic and diastolic blood pressure. With that, heat discomfort was more in cold season, than in warm one, this necessitates decrease of thermal load in cold season vs. the warm one.
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The vulva skin microclimate: influence of panty liners on temperature, humidity and pH.
Runeman, Bo; Rybo, Göran; Larkö, Olle; Faergemann, Jan
2003-01-01
Many women use panty liners between menstrual periods. The aim of this study was to investigate whether the use of such products might influence the vulva skin. Twelve healthy women were studied on four occasions with three different product constructions and on one occasion without products. Temperature, surface wetness and surface pH were measured on vulva skin. Mean skin temperature when the women were wearing a conventional panty liner (with a non-breathable back sheet) was 35.9 degrees C, compared to 34.4 degrees C when wearing no panty liner at all (p < 0.01) and 34.5 degrees C when using a panty liner with a breathable (i.e. vapour permeable) back sheet (p < 0.01). Skin humidity was significantly higher when the conventional panty liner was used compared to no panty liner or to the breathable panty liner (both cases p < 0.01). The mean pH value at the exterior aspect of the labium majus was 5.8 with the conventional panty liner, 5.2 with no panty liner and 5.3 with the breathable panty liner (p < 0.001 and p < 0.01, respectively). The results indicate that the conventional panty liner changes the vulva skin microclimate, but that the breathable panty liner to a substantial degree keeps the microclimate at an undisturbed level. The actual effect of these differences on microbiological flora will be addressed in a subsequent study.
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Glitz, K J; Seibel, U; Rohde, U; Gorges, W; Witzki, A; Piekarski, C; Leyk, D
2015-01-01
Heat stress caused by protective clothing limits work time. Performance improvement of a microclimate cooling method that enhances evaporative and to a minor extent convective heat loss was tested. Ten male volunteers in protective overalls completed a work-rest schedule (130 min; treadmill: 3 × 30 min, 3 km/h, 5% incline) with or without an additional air-diffusing garment (climatic chamber: 25°C, 50% RH, 0.2 m/s wind). Heat loss was supported by ventilating the garment with dry air (600 l/min, ≪5% RH, 25°C). Ventilation leads (M ± SD, n = 10, ventilated vs. non-ventilated) to substantial strain reduction (max. HR: 123 ± 12 b/min vs. 149 ± 24 b/min) by thermal relief (max. core temperature: 37.8 ± 0.3°C vs. 38.4 ± 0.4°C, max. mean skin temperature: 34.7 ± 0.8°C vs. 37.1 ± 0.3°C) and offers essential extensions in performance and work time under thermal insulation. Heat stress caused by protective clothing limits work time. Performance can be improved by a microclimate cooling method that supports evaporative and to a minor extent convective heat loss. Sweat evaporation is the most effective thermoregulatory mechanism for heat dissipation and can be enhanced by insufflating dry air into clothing.
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Keith Reinhardt; William K. Smith
2010-01-01
The red spruce-Fraser fir ecosystem (Picea rubens Sarg.-Abies fraseri [Pursh] Poir.) of the southern Appalachian mountains is a temperate zone cloud forest immersed in clouds for 30 to 40 percent of a typical summer day, and experiencing immersion on about 65 percent of all days annually. We compared the microclimate,...
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Intestinal alkaline phosphatase regulates protective surface microclimate pH in rat duodenum.
Mizumori, Misa; Ham, Maggie; Guth, Paul H; Engel, Eli; Kaunitz, Jonathan D; Akiba, Yasutada
2009-07-15
Regulation of localized extracellular pH (pH(o)) maintains normal organ function. An alkaline microclimate overlying the duodenal enterocyte brush border protects the mucosa from luminal acid. We hypothesized that intestinal alkaline phosphatase (IAP) regulates pH(o) due to pH-sensitive ATP hydrolysis as part of an ecto-purinergic pH regulatory system, comprised of cell-surface P2Y receptors and ATP-stimulated duodenal bicarbonate secretion (DBS). To test this hypothesis, we measured DBS in a perfused rat duodenal loop, examining the effect of the competitive alkaline phosphatase inhibitor glycerol phosphate (GP), the ecto-nucleoside triphosphate diphosphohydrolase inhibitor ARL67156, and exogenous nucleotides or P2 receptor agonists on DBS. Furthermore, we measured perfusate ATP concentration with a luciferin-luciferase bioassay. IAP inhibition increased DBS and luminal ATP output. Increased luminal ATP output was partially CFTR dependent, but was not due to cellular injury. Immunofluorescence localized the P2Y(1) receptor to the brush border membrane of duodenal villi. The P2Y(1) agonist 2-methylthio-ADP increased DBS, whereas the P2Y(1) antagonist MRS2179 reduced ATP- or GP-induced DBS. Acid perfusion augmented DBS and ATP release, further enhanced by the IAP inhibitor l-cysteine, and reduced by the exogenous ATPase apyrase. Furthermore, MRS2179 or the highly selective P2Y(1) antagonist MRS2500 co-perfused with acid induced epithelial injury, suggesting that IAP/ATP/P2Y signalling protects the mucosa from acid injury. Increased DBS augments IAP activity presumably by raising pH(o), increasing the rate of ATP degradation, decreasing ATP-mediated DBS, forming a negative feedback loop. The duodenal epithelial brush border IAP-P2Y-HCO(3-) surface microclimate pH regulatory system effectively protects the mucosa from acid injury.
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Sedov, A V; Kustov, V V; Surovtsev, N A; Lukicheva, T A; Akin'shin, A V; Nazarov, L Iu; Stroganov, V P
1991-01-01
Basing on experimental data, it was established that single administration of 0.5 mg bemitil increased human resistance to carbon oxide in concentration 300 mg/m3. The use of bemitil optimized human body state in the conditions of the complex influence of carbon oxide and extreme heating microclimate.
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NASA Astrophysics Data System (ADS)
Duthie, L.; Hyslop, E.; Lee, M.; Phoenix, V.; Kennedy, C.
2009-04-01
The impact of our changing climate on the historic built environment of Scotland has received surprisingly little attention. Current projections indicate that Scotland will become notably wetter and warmer over the coming decades. Winter temperatures are predicted to increase by 30C with 15% more precipitation, one result should be more aggressive microbial weathering of the sandstone buildings. In order to understand better and to quantify the damage potentially caused, it is necessary to analyse existing microbial populations but also to characterize conditions within building stones, how they change over diurnal and seasonal cycles, and how they differ from external conditions. In this study, temperature, humidity and moisture sensors were inserted at different depths into representative Scottish sandstones to record parameters key to microbial colonisation and organic weathering. Penetration of photosynthetically active radiation has also been measured. The within-stone data were compared to meteorological conditions recorded by an adjacent weather station. These data have then been compared with analysis of the microbial populations at different depths within the stone, using osmium stained polished blocks. Notably, microbes occur up to 7 mm beneath the outer sandstone surface, with community structure differing with depth. Clearly, different communities experience very different conditions within the stone, reflecting trophic structure, light penetration and microclimate. The sensor data confirm that temperature and water availability all vary within the stone and differ considerably with the external environment. We conclude that the warm and humid microclimate within Scottish building stones promotes microbial colonisation and stone decay and both will increase significantly with the changing climate of Scotland and north-west Europe.
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Pierce, K.L.; Colman, Steven M.
1986-01-01
Examines the effects of scarp size (height) and orientation (microclimate) by keeping constant variables such as age, lithology, and regional climate. For scarps 2m high, the degradation rate on S-facing scarps is 2 times that on N-facing scarps; for 10-m scarps, it is 5 times. Scarp morphology may be used to estimate age. -from Authors
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NASA Technical Reports Server (NTRS)
Machablishvili, O. G.
1980-01-01
The thermal state of women during the effect of high air temperature and relative humidity with a varying degree of physical loads was studied. Parameters for air temperature, relative humidity, and air movement were established. It was established that in women the thermo-regulatory stress occurs at lower air temperatures and with lower physical loads than in men. The accumulation of heat in women was revealed with lower air temperature than in men. It is concluded that to preserve the normal physiological state of the female organism it is necessary to create more favorable microclimate conditions and decrease the physical loads.
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NASA Astrophysics Data System (ADS)
Prorokova, M. V.; Bukhmirov, V. V.
2016-02-01
The article describes the method of valuation of comfort of microclimate of residen-tial, public and administrative buildings. The method is based on calculation of the coefficient of thermal comfort of a person in the room. Further amendments are introduced to the asym-metry of the thermal radiation, radiation cooling and air quality. The method serves as the basis for a computer program.
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Yoshimura, Mine; Nakagami, Gojiro; Iizaka, Shinji; Yoshida, Mikako; Uehata, Yoko; Kohno, Michihiro; Kasuya, Yusuke; Mae, Tomoko; Yamasaki, Takashi; Sanada, Hiromi
2015-01-01
Preventing pressure ulcers is important in patients undergoing procedures in the park-bench position. We hypothesized that the microclimate around the skin is a significant risk factor for developing pressure ulcers. This research continuously assessed factors of the microclimate in terms of skin temperature and perspiration as well as the interface pressure in order to determine whether the microclimate is an independent risk factor for the development of park-bench position-related pressure ulcers (PBP-PUs). A prospective observational study was conducted among patients undergoing elective surgery in the park-bench position at a general hospital in the metropolitan area of Japan between April and November 2014. Factors of the microclimate, including skin temperature and perspiration, in addition to the interface pressure were continuously measured throughout surgery. Twenty-nine patients were analyzed (mean age 44.4 ± 13.2 years, male 44.8%). Of these 29 patients, seven (24.1%) developed Category I PBP-PUs. The change in skin temperature from baseline to the end of surgery (2.7 ± 0.3 °C vs. 1.9 ± 0.8 °C) and the average peak pressure (119.1 ± 36.8 mmHg vs. 94.5 ± 23.1 mmHg) were significantly higher in the patients with PBP-PUs than in those without PBP-PUs. There were no significant differences in the amount of perspiration between the two groups. A hierarchical logistic regression analysis showed that the change in skin temperature was significantly related to the development of PBP-PUs (unit = 0.1 °C: odds ratio 1.44, 95% confidential interval 1.09-2.33) when adjusted for the average peak pressure and length of surgery. Our results suggest that a change in skin temperature toward a higher value is an independent risk factor for the development of PBP-PUs. Proper intraoperative management of skin temperature may therefore be a promising candidate as a preventive method against PBP-PU development. © 2015 by the Wound
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Hunsche, Mauricio; Blanke, Michael M; Noga, Georg
2010-08-15
A higher frequency of hail storms, possibly due to climate change, has led to increased installation of hail nets worldwide. The objective of the present work was to investigate potential effects of the microclimate under these hail nets on micromorphological characteristics of the leaves and adaxial leaf cuticles. Leaves of apple cultivars 'Pinova' and 'Fuji' grown on trees under white (highly translucent) or red-black (low transmittance) hail nets or on uncovered (control) trees were evaluated in June, August, September and October. The microclimate under the colored hail nets had no impact on leaf micromorphology, amount of cuticular wax, or leaf thickness. Similarly, no differences in thickness and permeability for calcium could be established between cuticles of leaves grown on trees under the two types of hail nets or uncovered trees. For all evaluated parameters, significant differences were detected between the two cultivars examined. In both cultivars, leaf wax synthesis followed a characteristic curve, increasing from the first to the second evaluation, and then decreasing continuously without affecting cuticular penetration of calcium. Overall, our results show that a reduction of the hail nets by 6-10% in both light and humidity was insufficient to influence the surface properties of apple leaves and permeability of cuticles. This may suggest that pest management strategies, i.e. formulation of agrochemicals, their application and dose, do not need to be adapted when used under hail nets. Overall, the present results indicate that the microclimatic changes brought about by colored hail nets are sufficient to enhance the vegetative growth and induce the 'shade avoidance syndrome', but do not appear to affect the leaf cuticular properties. Copyright 2010 Elsevier GmbH. All rights reserved.
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Morrison, Lucas M; Unger, Kirk A; Watterson, James H
2017-07-01
Analysis of dextromethorphan (DXM) and its metabolite dextrorphan (DXT) in skeletal remains of rats following acute (ACU, 75 mg/kg, IP, n = 10) or three repeated (REP, 25 mg/kg, IP, n = 10, 40-min interval) doses of DXM is described. Following dosing and euthanasia, rats decomposed outdoors to skeleton in two different microclimate environments (n = 5 ACU and n = 5 REP at each site): Site A (shaded forest microenvironment) and Site B (rocky substrate exposed to direct sunlight, 600 m from Site A). Two drug-free rats at each site served as negative controls. Skeletal elements (vertebrae, ribs, pelvic girdles, femora, tibiae, skulls and scapulae) were recovered, pulverized and underwent methanolic microwave assisted extraction (MAE). Extracts were analyzed by GC-MS following clean-up by solid-phase extraction (SPE). Drug levels, expressed as mass-normalized response ratios and the ratios of DXT and DXM levels (RRDXT/RRDXM) were compared between drug exposures, microclimate sites, and across skeletal elements. DXM levels differed significantly (P < 0.05) between corresponding bone elements across exposure groups (5/7-site A; 4/7-site B), but no significant differences in DXT levels were observed between corresponding elements. RRDXT/RRDXM differed significantly (P < 0.05) between corresponding bone elements across exposure groups (6/7-site A; 5/7-site B). No significant differences were observed in levels of DXM, DXT or RRDXT/RRDXM between corresponding elements from either group between sites. When data from all bone elements was pooled, levels of DXM and RRDXT/RRDXM differed significantly between exposure groups at each site, while those of DXT did not. For both exposure groups, comparison of pooled data between sites showed no significant differences in levels of DXM, DXT or RRDXT/RRDXM. Different decomposition microclimates did not impede the discrimination of DXM exposure patterns from the analyses of DXM, DXT and RRDXT/RRDXM in bone samples. © The Author 2017
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Vineyard microclimate and yield under different plastic covers.
Holcman, Ester; Sentelhas, Paulo Cesar; Conceição, Marco Antônio Fonseca; Couto, Hilton Thadeu Zarate
2018-06-01
The use of plastic cover in vineyards minimizes effects of adverse weather conditions. The northwest of São Paulo State is one of the largest grape producing regions in Brazil; however, few studies investigate the effects of different plastic covers on vineyards in this region. This study compared the effect of black shading screen (BSS) and braided polypropylene film (BPF) on BRS Morena vineyard microclimate, grown on an overhead trellis system in the northwestern São Paulo. The experiments were carried out during three growing seasons (2012-2014). BSS allowed superior incoming solar radiation (SR) transmissivity, resulting in higher net radiation (Rn), and higher ratio between photosynthetically active (PAR) and SR. No differences were observed between the average air temperatures (T) and relative humidity (RH) of covered environments (BPF and BSS) and outside condition (automatic weather station-AWS), due to high air circulation, despite wind speed (WS) reduction caused by plastic covers. BPF provided better conditions for vineyard growth with higher fruit yield than vineyard under BSS regarding the number of shoots with bunches per plant, bunch and stem weights, longitudinal diameter of berries, quantity of fertile buds per shoot, and yield per shoot and per plant. BPF covers also influenced leaf size and growth speed of plants in vineyards.
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Vineyard microclimate and yield under different plastic covers
NASA Astrophysics Data System (ADS)
Holcman, Ester; Sentelhas, Paulo Cesar; Conceição, Marco Antônio Fonseca; Couto, Hilton Thadeu Zarate
2017-12-01
The use of plastic cover in vineyards minimizes effects of adverse weather conditions. The northwest of São Paulo State is one of the largest grape producing regions in Brazil; however, few studies investigate the effects of different plastic covers on vineyards in this region. This study compared the effect of black shading screen (BSS) and braided polypropylene film (BPF) on BRS Morena vineyard microclimate, grown on an overhead trellis system in the northwestern São Paulo. The experiments were carried out during three growing seasons (2012-2014). BSS allowed superior incoming solar radiation (SR) transmissivity, resulting in higher net radiation (Rn), and higher ratio between photosynthetically active (PAR) and SR. No differences were observed between the average air temperatures (T) and relative humidity (RH) of covered environments (BPF and BSS) and outside condition (automatic weather station-AWS), due to high air circulation, despite wind speed (WS) reduction caused by plastic covers. BPF provided better conditions for vineyard growth with higher fruit yield than vineyard under BSS regarding the number of shoots with bunches per plant, bunch and stem weights, longitudinal diameter of berries, quantity of fertile buds per shoot, and yield per shoot and per plant. BPF covers also influenced leaf size and growth speed of plants in vineyards.
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Vineyard microclimate and yield under different plastic covers
NASA Astrophysics Data System (ADS)
Holcman, Ester; Sentelhas, Paulo Cesar; Conceição, Marco Antônio Fonseca; Couto, Hilton Thadeu Zarate
2018-06-01
The use of plastic cover in vineyards minimizes effects of adverse weather conditions. The northwest of São Paulo State is one of the largest grape producing regions in Brazil; however, few studies investigate the effects of different plastic covers on vineyards in this region. This study compared the effect of black shading screen (BSS) and braided polypropylene film (BPF) on BRS Morena vineyard microclimate, grown on an overhead trellis system in the northwestern São Paulo. The experiments were carried out during three growing seasons (2012-2014). BSS allowed superior incoming solar radiation (SR) transmissivity, resulting in higher net radiation (Rn), and higher ratio between photosynthetically active (PAR) and SR. No differences were observed between the average air temperatures (T) and relative humidity (RH) of covered environments (BPF and BSS) and outside condition (automatic weather station-AWS), due to high air circulation, despite wind speed (WS) reduction caused by plastic covers. BPF provided better conditions for vineyard growth with higher fruit yield than vineyard under BSS regarding the number of shoots with bunches per plant, bunch and stem weights, longitudinal diameter of berries, quantity of fertile buds per shoot, and yield per shoot and per plant. BPF covers also influenced leaf size and growth speed of plants in vineyards.
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USDA-ARS?s Scientific Manuscript database
Soil and irrigation management have been used to optimize crop production; however,their effects on microclimate, development, and potato diseases have not been adequately quantified. The effects of soil, crop, and water management on development of potato early blight and late blight were quantifie...
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2012-01-01
Background This paper discusses results obtained in the second monitoring campaign of the Carcer Tullianum, a particular hypogeum environment located in the historical centre of Rome (Italy). In the first paper we stressed the need to apply chemometric tools to this kind of studies in order to obtain full and significant information; really information on sampling design, sensors (type, number, position) and instrument validation seems to be not easy to find in literature for researches dealing with monitoring of indoor environments. Also in this case three main parameters (temperature, humidity, illuminance) were monitored in the complex construction by an inexpensive self-assembled system along some horizontal and vertical vectors together with some measurements of oxygen, carbon dioxide and barometric pressure. With respect to the first campaign, we used a higher number of sensors to cover a new excavated zone; for the same reason, as well as to take into account the presence of visitors, a different experimental design was adopted. Results Different data treatments were applied to data coming from all the used sensors. A good view of the microclimate was obtained that also resulted coherent with the different position of the three rooms constituting the monitored site (Carcer, Tullianum, Convent). Classical time plots resulted useful to evidence the correlation of the main monitored parameters (T, RH% and illuminance) with macroclimate, as well as their delay in following macroclimate. Box-Whisker and Gain-Loss graphs evidenced at the best the microclimate differences between the three rooms; an almost hypogean microclimate was evidenced for the lower room (Tullianum) where humidity values range between 90 and 100% while lower values, but anyway higher than the external, and spread more widely were measured passing to Convent and Carcer with minimum values around 50% for the last. A scarce or very scarce correlation with macroclimate was evidenced for all the
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Lapko, I V; Kir'iakov, V A; Antoshina, L I; Pavlovskaia, N A; Kondratovich, S V
2014-01-01
The authors studied influence of vibration, noise, physical overexertion and microclimate on carbohydrates metabolism and insulin resistance in metal mining industry workers. Findings are that vibration disease appeared to have maximal effect on insulin resistance test results and insulin level. The authors suggested biomarkers for early diagnosis of insulin resistance disorders in metal mining industry workers.
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du Plessis, Kari; Jacobson, Dan A.
2016-01-01
In this study, the metabolic and physiological impacts of an altered microclimate on quality-associated primary and secondary metabolites in grape (Vitis vinifera) ‘Sauvignon Blanc’ berries was determined in a high-altitude vineyard. The leaf and lateral shoot removal in the bunch zones altered the microclimate by increasing the exposure of the berries. The physical parameters (berry diameter and weight), primary metabolites (sugars and organic acids), as well as bunch temperature and leaf water potential were predominantly not affected by the treatment. The increased exposure led to higher levels of specific carotenoids and volatile terpenoids in the exposed berries, with earlier berry stages reacting distinctly from the later developmental stages. Plastic/nonplastic metabolite responses could be further classified to identify metabolites that were developmentally controlled and/or responded to the treatment in a predictable fashion (assessed over two consecutive vintages). The study demonstrates that grapevine berries exhibit a degree of plasticity within their secondary metabolites and respond physiologically to the increased exposure by increasing metabolites with potential antioxidant activity. Taken together, the data provide evidence that the underlying physiological responses relate to the maintenance of stress pathways by modulating antioxidant molecules in the berries. PMID:26628747
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Local- and landscape-scale land cover affects microclimate and water use in urban gardens.
Lin, Brenda B; Egerer, Monika H; Liere, Heidi; Jha, Shalene; Bichier, Peter; Philpott, Stacy M
2018-01-01
Urban gardens in Central California are highly vulnerable to the effects of climate change, experiencing both extended high heat periods as well as water restrictions because of severe drought conditions. This puts these critical community-based food production systems at risk as California is expected to experience increasing weather extremes. In agricultural systems, increased vegetation complexity, such as greater structure or biodiversity, can increase the resilience of food production systems from climate fluctuations. We test this theory in 15 urban gardens across California's Central Coast. Local- and landscape-scale measures of ground, vegetation, and land cover were collected in and around each garden, while climate loggers recorded temperatures in each garden in 30min increments. Multivariate analyses, using county as a random factor, show that both local- and landscape-scale factors were important. All factors were significant predictors of mean temperature. Tallest vegetation, tree/shrub species richness, grass cover, mulch cover, and landscape level agricultural cover were cooling factors; in contrast, garden size, garden age, rock cover, herbaceous species richness, and landscape level urban cover were warming factors. Results were similar for the maximum temperature analysis except that agriculture land cover and herbaceous species richness were not significant predictors of maximum temperature. Analysis of gardener watering behavior to observed temperatures shows that garden microclimate was significantly related to the number of minutes watered as well as the number of liters of water used per watering event. Thus gardeners seem to respond to garden microclimate in their watering behavior even though this behavior is most probably motivated by a range of other factors such as water regulations and time availability. This research shows that local management of ground cover and vegetation can reduce mean and maximum temperatures in gardens, and the
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Young, Philip R.; Eyeghe-Bickong, Hans A.; du Plessis, Kari
In this paper, the metabolic and physiological impacts of an altered microclimate on quality-associated primary and secondary metabolites in grape (Vitis vinifera) ‘Sauvignon Blanc’ berries was determined in a high-altitude vineyard. The leaf and lateral shoot removal in the bunch zones altered the microclimate by increasing the exposure of the berries. The physical parameters (berry diameter and weight), primary metabolites (sugars and organic acids), as well as bunch temperature and leaf water potential were predominantly not affected by the treatment. The increased exposure led to higher levels of specific carotenoids and volatile terpenoids in the exposed berries, with earlier berrymore » stages reacting distinctly from the later developmental stages. Plastic/nonplastic metabolite responses could be further classified to identify metabolites that were developmentally controlled and/or responded to the treatment in a predictable fashion (assessed over two consecutive vintages). The study demonstrates that grapevine berries exhibit a degree of plasticity within their secondary metabolites and respond physiologically to the increased exposure by increasing metabolites with potential antioxidant activity. Finally, taken together, the data provide evidence that the underlying physiological responses relate to the maintenance of stress pathways by modulating antioxidant molecules in the berries.« less
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Young, Philip R.; Eyeghe-Bickong, Hans A.; du Plessis, Kari; ...
2015-12-01
In this paper, the metabolic and physiological impacts of an altered microclimate on quality-associated primary and secondary metabolites in grape (Vitis vinifera) ‘Sauvignon Blanc’ berries was determined in a high-altitude vineyard. The leaf and lateral shoot removal in the bunch zones altered the microclimate by increasing the exposure of the berries. The physical parameters (berry diameter and weight), primary metabolites (sugars and organic acids), as well as bunch temperature and leaf water potential were predominantly not affected by the treatment. The increased exposure led to higher levels of specific carotenoids and volatile terpenoids in the exposed berries, with earlier berrymore » stages reacting distinctly from the later developmental stages. Plastic/nonplastic metabolite responses could be further classified to identify metabolites that were developmentally controlled and/or responded to the treatment in a predictable fashion (assessed over two consecutive vintages). The study demonstrates that grapevine berries exhibit a degree of plasticity within their secondary metabolites and respond physiologically to the increased exposure by increasing metabolites with potential antioxidant activity. Finally, taken together, the data provide evidence that the underlying physiological responses relate to the maintenance of stress pathways by modulating antioxidant molecules in the berries.« less
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Young, Philip R; Eyeghe-Bickong, Hans A; du Plessis, Kari; Alexandersson, Erik; Jacobson, Dan A; Coetzee, Zelmari; Deloire, Alain; Vivier, Melané A
2016-03-01
In this study, the metabolic and physiological impacts of an altered microclimate on quality-associated primary and secondary metabolites in grape (Vitis vinifera) 'Sauvignon Blanc' berries was determined in a high-altitude vineyard. The leaf and lateral shoot removal in the bunch zones altered the microclimate by increasing the exposure of the berries. The physical parameters (berry diameter and weight), primary metabolites (sugars and organic acids), as well as bunch temperature and leaf water potential were predominantly not affected by the treatment. The increased exposure led to higher levels of specific carotenoids and volatile terpenoids in the exposed berries, with earlier berry stages reacting distinctly from the later developmental stages. Plastic/nonplastic metabolite responses could be further classified to identify metabolites that were developmentally controlled and/or responded to the treatment in a predictable fashion (assessed over two consecutive vintages). The study demonstrates that grapevine berries exhibit a degree of plasticity within their secondary metabolites and respond physiologically to the increased exposure by increasing metabolites with potential antioxidant activity. Taken together, the data provide evidence that the underlying physiological responses relate to the maintenance of stress pathways by modulating antioxidant molecules in the berries. © 2016 American Society of Plant Biologists. All Rights Reserved.
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Forriez, O; Masseline, J; Coadic, D; David, V; Trouiller, P; Sztrymf, B
2017-02-02
To test the effect of a new coverlet device, allowing air circulation at the body/underlying surface interface, on skin microclimate management. This prospective observational pilot study took place in a 15-bed university-affiliated intensive care unit. Overall, 34 mechanically ventilated patients were included. Skin humidity and temperature were monitored before and after the implementation of the tested device at the occiput, scapulas, buttocks and sacrum. Humidity and temperature were evaluated through surface skin impedance and an infra-red thermometer, respectively. Health professionals were asked to evaluate the device. After implementation of the coverlet device, there was a rapid, sustained and significant decrease in skin humidity at all sites ranging from 6 % to 15 %, excluding the occiput. Skin temperature also significantly decreased from 1 % at both scapulas, but not at the other studied body sites. No side effects were observed. Health professionals reported that the device was easy and quick to install. Although they did not report a subjective improvement in skin moisture or temperature, they considered the device to be efficient. Although limited by its design, this pilot study suggests a good efficacy of the studied device on skin microclimate management. Further data are warranted to test the clinical implications of our findings.
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Grape aroma precursors in cv. Nebbiolo as affected by vine microclimate.
Asproudi, Andriani; Petrozziello, Maurizio; Cavalletto, Silvia; Guidoni, Silvia
2016-11-15
The influence exerted by bunch microclimate on some C13-norisoprenoid precursors content was investigated for the first time in Nebbiolo grapes during ripening. Samples were collected, during two consecutive seasons, from two vineyards, which are characterized by different microclimatic conditions caused by vine vigour heterogeneity and different vineyard aspects. Enzymatic hydrolysis of the glycosides extracted from the grapes, and subsequent GC-MS determination of the aglycones, highlighted that the majority of norisoprenoid glycosides accumulated in Nebbiolo berries from pre-veraison until 3-4weeks post-veraison. Vineyard aspect and vine vigour affected the timing of the maximum concentration of norisoprenoid precursors and their subsequent decrease at harvest. Low light in the vigorous blocks penalized norisoprenoids peak concentration. In the south less vigorous blocks, a decline of total norisoprenoids content during the pre-harvest period was observed. This decline appeared mainly regulated by the temperature. Vintage and/or microclimatic conditions affected the final content of some important norisoprenoids. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Grape cluster microclimate influences the aroma composition of Sauvignon blanc wine.
Martin, Damian; Grose, Claire; Fedrizzi, Bruno; Stuart, Lily; Albright, Abby; McLachlan, Andrew
2016-11-01
New Zealand Sauvignon blanc (SB) wines are characterised by a distinctive combination of tropical-fruity and green-herbaceous aromatic compounds. The influence of sunlight exposure of grape clusters on juice and wine composition was investigated, with the aim of manipulating aromatic compounds in SB wine. In the absence of basal leaf removal SB clusters naturally exposed to sunlight were riper than shaded clusters, evidenced by higher total soluble solids (TSS) and proline, and lower malic acid, 3-isobutyl-2-methoxypyrazine (IBMP) and arginine. Volatile thiols in wines did not differ between shaded and exposed clusters. At equivalent TSS, cluster exposure had little or no effect on malic acid concentration. Conversely, wine from shaded clusters had almost double the IBMP concentration of wine from exposed clusters at equivalent TSS. The effects on SB juice and wine composition of natural variations in cluster microclimate are not comparable with the effects of cluster exposure created through leaf removal. Copyright © 2016 Elsevier Ltd. All rights reserved.
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USDA-ARS?s Scientific Manuscript database
Microclimate variables were integrated over a six-month period during which blueberry (Vaccinium corymbosum cv. Liberty) bushes were grown in 51-cm high, 20-cm diameter round grow tubes (opaque or translucent) on a sawdust mulch-covered raised bed with the mulch incorporated into tilled soil. Grow t...
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Influence of Microclimate on Semi-Arid Montane Conifer Forest Sapflux Velocity in Complex Terrain
NASA Astrophysics Data System (ADS)
Thirouin, K. R.; Barnard, D. M.; Barnard, H. R.
2016-12-01
Microclimate variation in complex terrain is key to our understanding of large-scale climate change effects on montane ecosystems. Modern climate models forecast that semi-arid montane ecosystems in the western United States are to experience increases in temperature, number of extreme drought events, and decreases in annual snowpack, all of which will potentially influence ecosystem water, carbon, and energy balances. In this study, we developed response curves that describe the relationships between stem sapflux velocity, air temperature (Tair), incoming solar radiation (SWin), soil temperature (Tsoil), and soil moisture content (VWC) in sites of Pinus contorta and Pinus ponderosa distributed along an elevation and aspect gradient in the montane zone of the Central Rocky Mountains, Colorado, USA. Among sites we found sapflux velocity to be significantly correlated with all four environmental factors (p < 0.05), but most strongly with SWin and Tair. The response of sapflux velocity to SWin was logarithmic, whereas the response to Tair indicated a peak sapflux velocity at a site-specific temperature that declined with increasing Tair. Sapflux velocity also increased with increasing VWC, but decreased with increasing Tsoil. At south-facing sites, the initial increase in the logarithmic response curve for SWin leveled off at 150-250 W m-2, whereas for north-facing sites it leveled off at 50-125 W m-2. While the differences in the SWin response between aspects could be due to species physiological differences, the highest elevation south-facing P. contorta site behaved similarly to the south-facing P. ponderosa, suggesting that environmental drivers may dominate the response. In response to Tair, peak sapflux velocity occurred at 12-13 degrees C at all sites except the mid-slope north-facing P. contorta site, which also had the lowest Tsoil. The responses of stem sapflux velocity to climate drivers indicate that forest transpiration is regulated by microclimate
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Chambers, Ute; Jones, Vincent P
2015-12-01
Orchard design and management practices can alter microclimate and, thus, potentially affect insect development. If sufficiently large, these deviations in microclimate can compromise the accuracy of phenology model predictions used in integrated pest management (IPM) programs. Sunburn causes considerable damage in the Pacific Northwest, United States, apple-producing region. Common prevention strategies include the use of fruit surface protectants, evaporative cooling (EC), or both. This study focused on the effect of EC on ambient temperatures and model predictions for four insects (codling moth, Cydia pomonella L.; Lacanobia fruitworm, Lacanobia subjuncta Grote and Robinson; oblique-banded leafroller, Choristoneura rosaceana Harris; and Pandemis leafroller, Pandemis pyrusana Kearfott). Over-tree EC was applied in July and August when daily maximum temperatures were predicted to be ≥30°C between 1200-1700 hours (15/15 min on/off interval) in 2011 and between 1200-1800 hours (15/10 min on/off interval, or continuous on) in 2012. Control plots were sprayed once with kaolin clay in early July. During interval and continuous cooling, over-tree cooling reduced average afternoon temperatures compared with the kaolin treatment by 2.1-3.2°C. Compared with kaolin-treated controls, codling moth and Lacanobia fruitworm egg hatch in EC plots was predicted to occur up to 2 d and 1 d late, respectively. The presence of fourth-instar oblique-banded leafroller and Pandemis leafroller was predicted to occur up to 2 d and 1 d earlier in EC plots, respectively. These differences in model predictions were negligible, suggesting that no adjustments in pest management timing are needed when using EC in high-density apple orchards. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Scholl, M.A.; Gingerich, S.B.; Tribble, G.W.
2002-01-01
Stable isotopes of precipitation, ground water and surface water measured on the windward side of East Maui from 0 to 3055 m altitude were used to determine recharge sources for stream flow and ground water. Correct interpretation of the hydrology using rainfall ??18O gradients with altitude required consideration of the influence of fog, as fog samples had isotopic signatures enriched by as much as 3??? in ??18O and 21??? in ??D compared to volume-weighted average precipitation at the same altitude. The isotopic analyses suggested that fog drip was a major component of stream flow and shallow ground water at higher altitudes in the watershed. 18O/altitude gradients in rainfall were comparable for similar microclimates on Maui (this study) and Hawaii Island (1990-1995 study), however, East Maui ??18O values for rain in trade-wind and high-altitude microclimates were enriched compared to those from Hawaii Island. Isotopes were used to interpret regional hydrology in this volcanic island aquifer system. In part of the study area, stable isotopes indicate discharge of ground water recharged at least 1000 m above the sample site. This deep-flowpath ground water was found in springs from sea level up to 240 m altitude, indicating saturation to altitudes much higher than a typical freshwater lens. These findings help in predicting the effects of ground water development on stream flow in the area. Published by Elsevier Science B.V.
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2012-01-01
Too often microclimate studies in the field of cultural heritage are published without any or scarce information on sampling design, sensors (type, number, position) and instrument validation. Lacking of this fundamental information does not allow an open discussion in the scientific community. This work aims to be an invitation for a different approach. Three main parameters (temperature, humidity, luminance) were monitored in a selected part of a complex construction by an inexpensive self-assembled system along some horizontal and vertical vectors. All data was then processed and analyse by chemometric methods. Some measurements of oxygen, carbon monoxide and dioxide and pressure were also performed. Correlation of some indoor and outdoor data was shown for temperature and humidity. In case of outdoor changes the indoor environment reacted with a certain delay which is position-dependent and more evident for humidity data. The two observed rooms (Carcer and Tullianum) behave differently and the hypogean one is less influenced by the outdoor environment. Instrument validation before and after the campaign, allows to consider detected variations as significant. The fundamental importance of Sampling Design and of instrument validation before and after the monitoring campaign was enhanced. The choice of two main and two minor vectors allowed detection of different behaviour for the two rooms, also permitting to detect for both rooms a trend towards a spontaneous microclimate necessary for a conservation project. In the next campaign we will focus on the choice of the best sampling frequency to use more sophisticated statistical methods. PMID:22594436
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ERIC Educational Resources Information Center
Christensen, Mette K.; Lund, Ole
2014-01-01
Scholarly communities are dependent on and often measured by their ability to attract and develop doctoral students. Recent literature suggests that most scholarly communities entail ecological niches in which the doctoral students learn the codes and practices of research. In this article, we explore the microclimate in an ecological niche of…
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High-Resolution Urban Greenery Mapping for Micro-Climate Modelling Based on 3d City Models
NASA Astrophysics Data System (ADS)
Hofierka, J.; Gallay, M.; Kaňuk, J.; Šupinský, J.; Šašak, J.
2017-10-01
Urban greenery has various positive micro-climate effects including mitigation of heat islands. The primary root of heat islands in cities is in absorption of solar radiation by the mass of building structures, roads and other solid materials. The absorbed heat is subsequently re-radiated into the surroundings and increases ambient temperatures. The vegetation can stop and absorb most of incoming solar radiation mostly via the photosynthesis and evapotranspiration process. However, vegetation in mild climate of Europe manifests considerable annual seasonality which can also contribute to the seasonal change in the cooling effect of the vegetation on the urban climate. Modern methods of high-resolution mapping and new generations of sensors have brought opportunity to record the dynamics of urban greenery in a high resolution in spatial, spectral, and temporal domains. In this paper, we use the case study of the city of Košice in Eastern Slovakia to demonstrate the methodology of 3D mapping and modelling the urban greenery during one vegetation season in 2016. The purpose of this monitoring is to capture 3D effects of urban greenery on spatial distribution of solar radiation in urban environment. Terrestrial laser scanning was conducted on four selected sites within Košice in ultra-high spatial resolution. The entire study area, which included these four smaller sites, comprised 4 km2 of the central part of the city was flown within a single airborne lidar and photogrammetric mission to capture the upper parts of buildings and vegetation. The acquired airborne data were used to generate a 3D city model and the time series of terrestrial lidar data were integrated with the 3D city model. The results show that the terrestrial and airborne laser scanning techniques can be effectively used to monitor seasonal changes in foliage of trees in order to assess the transmissivity of the canopy for microclimate modelling.
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Merello, Paloma; García-Diego, Fernando-Juan; Zarzo, Manuel
2012-11-28
Ariadne's house, located at the city center of ancient Pompeii, is of great archaeological value due to the fresco paintings decorating several rooms. In order to assess the risks for long-term conservation affecting the valuable mural paintings, 26 temperature data-loggers and 26 relative humidity data-loggers were located in four rooms of the house for the monitoring of ambient conditions. Data recorded during 372 days were analyzed by means of graphical descriptive methods and analysis of variance (ANOVA). Results revealed an effect of the roof type and number of walls of the room. Excessive temperatures were observed during the summer in rooms covered with transparent roofs, and corrective actions were taken. Moreover, higher humidity values were recorded by sensors on the floor level. The present work provides guidelines about the type, number, calibration and position of thermohygrometric sensors recommended for the microclimate monitoring of mural paintings in outdoor or semi-confined environments.
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Wallace, K J; Laughlin, Daniel C; Clarkson, Bruce D
2017-06-01
Restoring forest structure and composition is an important component of urban land management, but we lack clear understanding of the mechanisms driving restoration success. Here we studied two indicators of restoration success in temperate rainforests: native tree regeneration and epiphyte colonization. We hypothesized that ecosystem properties such as forest canopy openness, abundance of exotic herbaceous weeds, and the microclimate directly affect the density and diversity of native tree seedlings and epiphytes. Relationships between environmental conditions and the plant community were investigated in 27 restored urban forests spanning 3-70 years in age and in unrestored and remnant urban forests. We used structural equation modelling to determine the direct and indirect drivers of native tree regeneration and epiphyte colonization in the restored forests. Compared to remnant forest, unrestored forest had fewer native canopy tree species, significantly more light reaching the forest floor annually, and higher exotic weed cover. Additionally, epiphyte density was lower and native tree regeneration density was marginally lower in the unrestored forests. In restored forests, light availability was reduced to levels found in remnant forests within 20 years of restoration planting, followed shortly thereafter by declines in herbaceous exotic weeds and reduced fluctuation of relative humidity and soil temperatures. Contrary to expectations, canopy openness was only an indirect driver of tree regeneration and epiphyte colonization, but it directly regulated weed cover and microclimatic fluctuations, both of which directly drove the density and richness of regeneration and epiphyte colonization. Epiphyte density and diversity were also positively related to forest basal area, as large trees provide physical habitat for colonization. These results imply that ecosystem properties change predictably after initial restoration plantings, and that reaching critical
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NASA Astrophysics Data System (ADS)
Garner, G.; Hannah, D. M.; Malcolm, I.; Sadler, J. P.
2012-12-01
Riparian forest is recognised as important for moderating stream temperature variability and has the potential to mitigate thermal extremes in a changing climate. Previous research on the heat exchanges controlling water column temperature has often been short-term or seasonally-constrained, with the few multi-year studies limited to a maximum of two years. This study advances previous work by providing a longer-term perspective which allows assessment of inter-annual variability in stream temperature, microclimate and heat exchange dynamics between a semi-natural woodland and a moorland (no trees) reach of the Girnock Burn, a tributary of the Scottish Dee. Automatic weather stations collected 15-minute data over seven consecutive years, which to our knowledge is a unique data set in providing the longest term perspective to date on stream temperature, microclimate and heat exchange processes. Results for spring-summer indicate that the presence of a riparian canopy has a consistent effect between years in reducing the magnitude and variability of mean daily water column temperature and daily net energy totals. Differences in the magnitude and variability in net energy fluxes between the study reaches were driven primarily by fluctuations in net radiation and latent heat fluxes in response to between- and within-year variability in growth of the riparian forest canopy at the forest and prevailing weather conditions at both the forest and moorland. This research provides new insights on the inter-annual variability of stream energy exchanges for moorland and forested reaches under a wide range of climatological and hydrological conditions. The findings therefore provide a more robust process basis for modelling the impact of changes in forest practice and climate change on river thermal dynamics.
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Baiocchi, Valerio; Zottele, Fabio; Dominici, Donatella
2017-01-01
This work reports a first attempt to use Landsat satellite imagery to identify possible urban microclimate changes in a city center after a seismic event that affected L’Aquila City (Abruzzo Region, Italy), on 6 April 2009. After the main seismic event, the collapse of part of the buildings, and the damaging of most of them, with the consequence of an almost total depopulation of the historic city center, may have caused alterations to the microclimate. This work develops an inexpensive work flow—using Landsat Enhanced Thematic Mapper Plus (ETM+) scenes—to construct the evolution of urban land use after the catastrophic main seismic event that hit L’Aquila. We hypothesized, that, possibly, before the event, the temperature was higher in the city center due to the presence of inhabitants (and thus home heating); while the opposite case occurred in the surrounding areas, where new settlements of inhabitants grew over a period of a few months. We decided not to look to independent meteorological data in order to avoid being biased in their investigations; thus, only the smallest dataset of Landsat ETM+ scenes were considered as input data in order to describe the thermal evolution of the land surface after the earthquake. We managed to use the Landsat archive images to provide thermal change indications, useful for understanding the urban changes induced by catastrophic events, setting up an easy to implement, robust, reproducible, and fast procedure. PMID:28218724
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Baiocchi, Valerio; Zottele, Fabio; Dominici, Donatella
2017-02-19
This work reports a first attempt to use Landsat satellite imagery to identify possible urban microclimate changes in a city center after a seismic event that affected L'Aquila City (Abruzzo Region, Italy), on 6 April 2009. After the main seismic event, the collapse of part of the buildings, and the damaging of most of them, with the consequence of an almost total depopulation of the historic city center, may have caused alterations to the microclimate. This work develops an inexpensive work flow-using Landsat Enhanced Thematic Mapper Plus (ETM+) scenes-to construct the evolution of urban land use after the catastrophic main seismic event that hit L'Aquila. We hypothesized, that, possibly, before the event, the temperature was higher in the city center due to the presence of inhabitants (and thus home heating); while the opposite case occurred in the surrounding areas, where new settlements of inhabitants grew over a period of a few months. We decided not to look to independent meteorological data in order to avoid being biased in their investigations; thus, only the smallest dataset of Landsat ETM+ scenes were considered as input data in order to describe the thermal evolution of the land surface after the earthquake. We managed to use the Landsat archive images to provide thermal change indications, useful for understanding the urban changes induced by catastrophic events, setting up an easy to implement, robust, reproducible, and fast procedure.
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Portable System for Monitoring the Microclimate in the Footwear-Foot Interface
Sandoval-Palomares, José de Jesús; Yáñez-Mendiola, Javier; Gómez-Espinosa, Alfonso; López-Vela, José Martin
2016-01-01
A new, continuously-monitoring portable device that monitors the diabetic foot has shown to help in reduction of diabetic foot complications. Persons affected by diabetic foot have shown to be particularly sensitive in the plantar surface; this sensitivity coupled with certain ambient conditions may cause dry skin. This dry skin leads to the formation of fissures that may eventually result in a foot ulceration and subsequent hospitalization. This new device monitors the micro-climate temperature and humidity areas between the insole and sole of the footwear. The monitoring system consists of an array of ten sensors that take readings of relative humidity within the range of 100% ± 2% and temperature within the range of −40 °C to 123.8 ± 0.3 °C. Continuous data is collected using embedded C software and the recorded data is processed in Matlab. This allows for the display of data; the implementation of the iterative Gauss-Newton algorithm method was used to display an exponential response curve. Therefore, the aim of our system is to obtain feedback data and provide the critical information to various footwear manufacturers. The footwear manufactures will utilize this critical information to design and manufacture diabetic footwear that reduce the risk of ulcers in diabetic feet. PMID:27399718
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2012-01-01
Background Ariadne’s house, located at the city center of ancient Pompeii, is of great archaeological value due to the fresco paintings decorating several rooms. In order to assess the risks for long-term conservation affecting the valuable mural paintings, 26 temperature data-loggers and 26 relative humidity data-loggers were located in four rooms of the house for the monitoring of ambient conditions. Results Data recorded during 372 days were analyzed by means of graphical descriptive methods and analysis of variance (ANOVA). Results revealed an effect of the roof type and number of walls of the room. Excessive temperatures were observed during the summer in rooms covered with transparent roofs, and corrective actions were taken. Moreover, higher humidity values were recorded by sensors on the floor level. Conclusions The present work provides guidelines about the type, number, calibration and position of thermohygrometric sensors recommended for the microclimate monitoring of mural paintings in outdoor or semi-confined environments. PMID:23190798
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Genz, Anne-Katrin; v Engelhardt, Wolfgang; Busche, Roger
1999-01-01
The fluorescent dye 5-N-hexadecanoyl-aminofluorescein (HAF) was used to study the mechanisms involved in maintaining a relatively constant luminal surface pH (pHs) in the distal colon of the guinea-pig. The fatty acyl chain of the HAF molecule inserts into the apical membrane of epithelial cells. This allows a continuous measurement of the surface pH for several hours. The localization of HAF was confirmed by confocal laser-scanning microscopy and by using monoclonal antibodies against fluorescein. The insertion of HAF into the apical membrane of the colonocytes did not change the transepithelial conductance or the short-circuit current of the epithelium. With the HAF method a pH microclimate was confirmed at the colonic surface. Although the pH of the bulk luminal solution was decreased in bicarbonate-containing solution from 7.4 to 6.4 the pHs changed only in the range 7.54-6.98. In the absence of bicarbonate pHs almost followed changes of bulk luminal pH. In the presence of bicarbonate there was a decrease in pHs after removal of chloride from the luminal side and an increase in pHs after addition of butyrate to the luminal solution. This suggests the involvement of a bicarbonate-anion exchange in bicarbonate secretion: a Cl−-HCO3− as well as a short-chain fatty acid−-HCO3− exchange. The apical K+-H+-ATPase in the distal colon of guinea-pig has little influence on pHs in the presence of physiological buffer concentrations. Our findings indicate that bicarbonate plays a major role in maintaining the pH microclimate at the colonic surface. PMID:10332098
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Influence of microclimate on the sustainability and reliability of weathering steel bridge
NASA Astrophysics Data System (ADS)
Kubzova, M.; Krivy, V.; Kreislova, K.
2018-04-01
Reliability and sustainability of bridge structures designed from weathering steel are influenced by the development of a sufficiently protective layer of corrosion products on its surface. The development of this protective layer is affected by several parameters such as air pollution around the bridge structure, the microclimate under the bridge, the location of surface within the bridge structure and the time of wetness. Design of structural details also significantly influences the development of the protective corrosion layer. The article deals with the results of the experimental tests carried out on the road bridge located in the city of Ostrava in the Czech Republic. The development of the protective corrosion layer on the surface of the bridge is significantly influenced by the intensive traffic under the bridge construction and the design solution of the bridge itself. Attention is focused mainly on the influence of chloride deposition on the protective function of the corrosion layer. Corrosion samples were placed on the bridge to evaluate the influence of the above-mentioned parameters. The deposition rate of chlorides spreading from the road to surfaces of the steel structure is also measured.
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Sidorchuk, N V; Rozhnov, V V
2008-01-01
Data on the microclimate (air temperature and humidity) within an unoccupied badger sett in the Darwin Reserve (the Vologda Region) between September 2005 and May 2006 have been analyzed in relation to changes in the temperature and humidity of the ground air layer and soil. A positive correlation has been revealed between the temperature regime of the soil and air temperature within the sett. After the establishment of snow cover, air and soil temperatures within the sett vary slightly and barely depend on ambient air temperature.
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NASA Technical Reports Server (NTRS)
Zimmermann, R.; McDonald, K.; Way, J.; Oren, R.
1994-01-01
Tree canopy microclimate, xylem water flux and xylem dielectric constant have been monitored in situ since June 1993 in two adjacent natural forest stands in central Alaska. The deciduous stand represents a mature balsam poplar site on the Tanana River floodplain, while the coniferous stand consists of mature white spruce with some black spruce mixed in. During solstice in June and later in summer, diurnal changes of xylem water potential were measured to investigate the occurrence and magnitude of tree transpiration and dielectric constant changes in stems.
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Fantuzzi, G; Righi, E; Predieri, G; Giacobazzi, P; Mastroianni, K; Aggazzotti, G
2010-01-01
The aim of the present study was to investigate the environmental and healthy aspects from a representative sample of indoor swimming pools located in the Emilia Romagna region. During the sampling sessions, the occupational environment was evaluated in terms of microclimate parameters and thermal comfort/discomfort conditions. Moreover the chemical risk was assessed by analyzing from the pool water the presence of disinfection by-products (DBPs), such as: trihalomethanes (THMs), haloacetic acids (HAAs), chlorite, chlorate and bromate. The analytical results are in agreement with the Italian legislation (Accordo Stato-Regioni; 2003) even if in some of the sampled indoor swimming pools, the dosed combined chlorine levels, were greater than the Italian limit. With the regard to the microclimate conditions evaluation, the considered thermal indices, Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD%), described a satisfactory occupational environment. Among DBPs, the THMs mean levels (41.4 +/- 30.0 microg/l) resulted close to the values of the current Italian drinking water legislation, and seem to not represent an health issue. The pool waters chlorate levels (range: 5 - 19537 microg/l) need further investigations as recent epidemiological studies on drinking water hypothesized a potential genotoxicity effect of these compounds which are involved in cellular oxidative processes.
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Impact of dangerous microclimate conditions within an enclosed vehicle on pediatric thermoregulation
NASA Astrophysics Data System (ADS)
Grundstein, Andrew; Duzinski, Sarah; Null, Jan
2017-01-01
Pediatric vehicular hyperthermia (PVH) persists as the leading cause of non-crash, vehicle-related deaths among US children with an average of 37 children dying after being left unattended in motor vehicles each year. Our study aims to demonstrate the microclimate conditions within an enclosed vehicle that lead infants and small children to reach key physiological heat thresholds: uncompensable heating (>37 °C) and heatstroke (>40 °C) under "worst case" conditions. A modified version of the Man-Environment Heat Exchange Model was used to compute the length of time for an infant to reach these thresholds. Several different scenarios were modeled using different initial cabin air temperatures. Assuming full sun exposure and maximum heating rates, an infant may reach uncompensable heating within 5 min and experience hyperthermia anywhere from 15 to 55 min depending on the starting cabin air temperature. The rapid approach of these heat-related thresholds occurs as enclosed vehicles maximize heating and minimize cooling mechanisms, leading to net heating and increase in core body temperatures. Health experts can use this information to support public health messaging on the topic of PVH by explaining why it is important to never leave a child alone in a car and increase the public perception of severity and susceptibility to this ongoing public health issue.
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Hübner, Sariel; Rashkovetsky, Eugenia; Kim, Young Bun; Oh, Jung Hun; Michalak, Katarzyna; Weiner, Dmitry; Korol, Abraham B.; Nevo, Eviatar; Michalak, Pawel
2013-01-01
The opposite slopes of “Evolution Canyon” in Israel have served as a natural model system of adaptation to a microclimate contrast. Long-term studies of Drosophila melanogaster populations inhabiting the canyon have exhibited significant interslope divergence in thermal and drought stress resistance, candidate genes, mobile elements, habitat choice, mating discrimination, and wing-shape variation, all despite close physical proximity of the contrasting habitats, as well as substantial interslope migration. To examine patterns of genetic differentiation at the genome-wide level, we used high coverage sequencing of the flies’ genomes. A total of 572 genes were significantly different in allele frequency between the slopes, 106 out of which were associated with 74 significantly overrepresented gene ontology (GO) terms, particularly so with response to stimulus and developmental and reproductive processes, thus corroborating previous observations of interslope divergence in stress response, life history, and mating functions. There were at least 37 chromosomal “islands” of interslope divergence and low sequence polymorphism, plausible signatures of selective sweeps, more abundant in flies derived from one (north-facing) of the slopes. Positive correlation between local recombination rate and the level of nucleotide polymorphism was also found. PMID:24324170
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NASA Astrophysics Data System (ADS)
Puspitasari, P.; Kadri, T.; Indartoyo, I.; Kusumawati, L.
2018-01-01
This paper aims to describe the results of preliminary research on floating houses on the Musi River, Seberang Ulu 1, Palembang, focused on studying the influence of microclimates to the tectonics of Rumah Rakit (Floating House). The increase of water surface due to global warming will increase the need of using floating house typology in the future. The description of the inhabitants’ experiences on applying technics to create vernacular floating houses is considered as significant knowledge to develop advance technology on the basis of local characteristic. Vernacular floating houses resilience consists of natural experiences of inhabitants in adapting their daily activities to the characteristic of local climate. By using qualitative approach, the Rumah Rakit inhabitants’ verbal information in this article becomes the main aspect in exploring local knowledge. At the end, the conceptual model of vernacular Rumah Rakit in Seberang Ulu 1, Palembang is formulated, in terms of building architectural tectonic that is closely related to the local climate characteristic. The knowledge can be utilized in the context of rehabilitation or preservation of such architectural objects that are their existences tend to be extinct at this time.
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Kim, Young Bun; Oh, Jung Hun; McIver, Lauren J.; Rashkovetsky, Eugenia; Michalak, Katarzyna; Garner, Harold R.; Kang, Lin; Nevo, Eviatar; Korol, Abraham B.; Michalak, Pawel
2014-01-01
Repeat sequences, especially mobile elements, make up large portions of most eukaryotic genomes and provide enormous, albeit commonly underappreciated, evolutionary potential. We analyzed repeatomes of Drosophila melanogaster that have been diverging in response to a microclimate contrast in Evolution Canyon (Mount Carmel, Israel), a natural evolutionary laboratory with two abutting slopes at an average distance of only 200 m, which pose a constant ecological challenge to their local biotas. Flies inhabiting the colder and more humid north-facing slope carried about 6% more transposable elements than those from the hot and dry south-facing slope, in parallel to a suite of other genetic and phenotypic differences between the two populations. Nearly 50% of all mobile element insertions were slope unique, with many of them disrupting coding sequences of genes critical for cognition, olfaction, and thermotolerance, consistent with the observed patterns of thermotolerance differences and assortative mating. PMID:25006263
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Kim, Young Bun; Oh, Jung Hun; McIver, Lauren J; Rashkovetsky, Eugenia; Michalak, Katarzyna; Garner, Harold R; Kang, Lin; Nevo, Eviatar; Korol, Abraham B; Michalak, Pawel
2014-07-22
Repeat sequences, especially mobile elements, make up large portions of most eukaryotic genomes and provide enormous, albeit commonly underappreciated, evolutionary potential. We analyzed repeatomes of Drosophila melanogaster that have been diverging in response to a microclimate contrast in Evolution Canyon (Mount Carmel, Israel), a natural evolutionary laboratory with two abutting slopes at an average distance of only 200 m, which pose a constant ecological challenge to their local biotas. Flies inhabiting the colder and more humid north-facing slope carried about 6% more transposable elements than those from the hot and dry south-facing slope, in parallel to a suite of other genetic and phenotypic differences between the two populations. Nearly 50% of all mobile element insertions were slope unique, with many of them disrupting coding sequences of genes critical for cognition, olfaction, and thermotolerance, consistent with the observed patterns of thermotolerance differences and assortative mating.
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Chan, Albert P C; Song, Wenfang; Yang, Yang
2015-01-01
This study aims to determine the appropriate microclimate cooling systems (MCSs) to reduce heat stress and improve human performance of occupational workers and their practicality in the occupational field. Meta-analysis was employed to summarize, analyze, and compare the effects of various MCSs on human performance with corresponding physiological and psychological responses, thereby providing solid suggestions for selecting suitable MCSs for occupational workers. Wearing MCSs significantly attenuated the increases in core temperature (-0.34 °C/h) and sweating rate (-0.30 L/h), and significantly improved human performance (+29.9%, effect size [EFS] = 1.1) compared with no cooling condition (CON). Cold air-cooled garments (ACG-Cs; +106.2%, EFS = 2.32) exhibited greater effects on improving human performance among various microclimate cooling garments (MCGs), followed by liquid cooling garments (LCGs; +68.1%, EFS = 1.86) and hybrid cooling garment combining air and liquid cooling (HBCG-AL; +59.1%, EFS=3.38), natural air-cooled garments (ACG-Ns; +39.9%, EFS = 1.12), and phase change material cooling garments (PCMCGs; +19.5%, EFS = 1.2). Performance improvement was observed to be positively and linearly correlated to the differences of core temperature increase rate (r = 0.65, p < 0.01) and sweating rate (r = 0.80, p < 0.001) between MCSs and CON. Considering their application in industrial settings, ACG-Cs, LCGs, and HBCG-AL are practical for work, in which workers do not move frequently, whereas ACG-Ns and PCMCGs are more applicable for the majority of occupational workers. Further enhancement of the cooling efficiency of these two cooling strategies should be initiated. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Mind the wind: microclimate effects on incubation effort of an arctic seabird.
Høyvik Hilde, Christoffer; Pélabon, Christophe; Guéry, Loreleï; Gabrielsen, Geir Wing; Descamps, Sébastien
2016-04-01
The energetic costs of reproduction in birds strongly depend on the climate experienced during incubation. Climate change and increasing frequency of extreme weather events may severely affect these costs, especially for species incubating in extreme environments. In this 3-year study, we used an experimental approach to investigate the effects of microclimate and nest shelter on the incubation effort of female common eiders (Somateria mollissima) in a wild Arctic population. We added artificial shelters to a random selection of nesting females, and compared incubation effort, measured as body mass loss during incubation, between females with and without shelter. Nonsheltered females had a higher incubation effort than females with artificial shelters. In nonsheltered females, higher wind speeds increased the incubation effort, while artificially sheltered females experienced no effect of wind. Although increasing ambient temperatures tended to decrease incubation effort, this effect was negligible in the absence of wind. Humidity had no marked effect on incubation effort. This study clearly displays the direct effect of a climatic variable on an important aspect of avian life-history. By showing that increasing wind speed counteracts the energetic benefits of a rising ambient temperature, we were able to demonstrate that a climatic variable other than temperature may also affect wild populations and need to be taken into account when predicting the effects of climate change.
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Cunningham, K.I.; LaRock, E.J.
1991-01-01
Radon concentrations range from <185 to 3,515 Bq m-3 throughout Lechuguilla Cave, Carlsbad Caverns National Park, New Mexico. Concentrations in the entrance passages and areas immediately adjacent to these passages are controlled by outside air temperature and barometric pressure, similar to other Type 2 caves. Most of the cave is developed in three geographic branches beneath the entrance passages; these areas maintain Rn levels independent of surface effects, an indication that Rn levels in deep, complex caves or mines cannot be simply estimated by outside atmospheric parameters. These deeper, more isolated areas are subject to convective ventilation driven by temperature differences along the 477-m vertical extent of the cave. Radon concentrations are used to delineate six microclimate zones (air circulation cells) throughout the cave in conjunction with observed airflow data. Suspected surface connections contribute fresh air to remote cave areas demonstrated by anomalous Rn lows surrounded by higher values, the presence of mammalian skeletal remains, CO2 concentrations and temperatures lower than the cave mean, and associated surficial karst features.
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Zhang, Pan-pan; Zhou, Yu; Song, Hui; Qiao, Zhi-jun; Wang, Hai-gang; Zheng, Dian-feng; Feng, Bai-li
2015-02-01
A field experiment with two broomcorn millet varieties Longmi 8 (strong drought-resistant variety) and Jinmi 4 (drought-sensitive variety) was conducted to compare their differences in growth, field microclimate and photosynthetic capacity from anthesis to maturity under different fertility conditions. The results showed that, fertilization decreased canopy temperature, air temperature, soil temperature, illumination, but improved the relative humidity among broomcorn millet plants compared with the non-fertilization treatment. With an increase of the fertilizer level, the plant height, SPAD, LAI, net photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO2 concentration in broomcorn millet showed an increasing trend, which of the high fertilization treatment were 9.2%, 15.1%, 56.6%, 17.8%, 24.6%, 14.2%, 29.7% higher than those of non-fertilization treatment, respectively. Compared with Jinmi 4, Longmi 8 showed a cold wet characteristic, with lower canopy temperature, air temperature, soil temperature; illumination, and higher plant height, LAI, SPAD and relative humidity during grain filling. Moreover, each photosynthetic index of Longmi 8 slowly decreased and extended the period of leaf photosynthetic function so as to accumulate more photosynthetic products.
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Urban geometry effects on the microclimate of streets near the river
NASA Astrophysics Data System (ADS)
Park, C.; Lee, D. K.; Asawa, T.; Murakami, A.; Kim, H. G.; Jeong, W.
2016-12-01
These days, many urbans have undergone urban heat islands (UHIs) which mean urban areas have higher temperature than surrounding areas. Because of UHIs, extreme heat waves and tropical nights threaten citizen's health. For reducing UHI effects, UHIs mitigation strategies related with urban planning (cooling elements, urban geometry, and urban materials) are studied in many fields. Especially, cooling elements such as vegetation and water are important for making sustainable cities. However, while the each effects of cooling elements are known, combination effects between urban geometry and elements are not clearly defined. To determine which urban geometry is effective to decrease air temperature, we analyzed urban geometry effects on the microclimate of streets near the river. The urban streets located in commercial area near the Cheonggye River and they had different aspect ratio. For doing this, we used field measurement. Field measurement were takin in the sunny days of July and August 2016. Air temperature measurement used T-type thermometers with cylindrical tube and ventilation fan. Wind measurements used kestrel 4500 for wind speed and wind direction. We measured air temperature in the screen level and repeated three times an hour. Measurement results showed that large aspect ratio street show lower air temperature than small ones. And they received cooling effect farther than others from the river. This is because that cooling air flows well in the wide road streets. Large aspect ratio streets are effective to receive river's cooling air. These results can be used in the urban geometry planning near the river.
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Assessment of microclimate conditions under artificial shades in a ginseng field.
Lee, Kyu Jong; Lee, Byun-Woo; Kang, Je Yong; Lee, Dong Yun; Jang, Soo Won; Kim, Kwang Soo
2016-01-01
Knowledge on microclimate conditions under artificial shades in a ginseng field would facilitate climate-aware management of ginseng production. Weather data were measured under the shade and outside the shade at two fields located in Gochang-gun and Jeongeup-si, Korea, in 2011 and 2012 seasons to assess temperature and humidity conditions under the shade. An empirical approach was developed and validated for the estimation of leaf wetness duration (LWD) using weather measurements outside the shade as inputs to the model. Air temperature and relative humidity were similar between under the shade and outside the shade. For example, temperature conditions favorable for ginseng growth, e.g., between 8°C and 27°C, occurred slightly less frequently in hours during night times under the shade (91%) than outside (92%). Humidity conditions favorable for development of a foliar disease, e.g., relative humidity > 70%, occurred slightly more frequently under the shade (84%) than outside (82%). Effectiveness of correction schemes to an empirical LWD model differed by rainfall conditions for the estimation of LWD under the shade using weather measurements outside the shade as inputs to the model. During dew eligible days, a correction scheme to an empirical LWD model was slightly effective (10%) in reducing estimation errors under the shade. However, another correction approach during rainfall eligible days reduced errors of LWD estimation by 17%. Weather measurements outside the shade and LWD estimates derived from these measurements would be useful as inputs for decision support systems to predict ginseng growth and disease development.
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Assessment of microclimate conditions under artificial shades in a ginseng field
Lee, Kyu Jong; Lee, Byun-Woo; Kang, Je Yong; Lee, Dong Yun; Jang, Soo Won; Kim, Kwang Soo
2015-01-01
Background Knowledge on microclimate conditions under artificial shades in a ginseng field would facilitate climate-aware management of ginseng production. Methods Weather data were measured under the shade and outside the shade at two fields located in Gochang-gun and Jeongeup-si, Korea, in 2011 and 2012 seasons to assess temperature and humidity conditions under the shade. An empirical approach was developed and validated for the estimation of leaf wetness duration (LWD) using weather measurements outside the shade as inputs to the model. Results Air temperature and relative humidity were similar between under the shade and outside the shade. For example, temperature conditions favorable for ginseng growth, e.g., between 8°C and 27°C, occurred slightly less frequently in hours during night times under the shade (91%) than outside (92%). Humidity conditions favorable for development of a foliar disease, e.g., relative humidity > 70%, occurred slightly more frequently under the shade (84%) than outside (82%). Effectiveness of correction schemes to an empirical LWD model differed by rainfall conditions for the estimation of LWD under the shade using weather measurements outside the shade as inputs to the model. During dew eligible days, a correction scheme to an empirical LWD model was slightly effective (10%) in reducing estimation errors under the shade. However, another correction approach during rainfall eligible days reduced errors of LWD estimation by 17%. Conclusion Weather measurements outside the shade and LWD estimates derived from these measurements would be useful as inputs for decision support systems to predict ginseng growth and disease development. PMID:26843827
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Effects of summer microclimates on behavior of lions and tigers in zoos.
Young, Tory; Finegan, Esther; Brown, Robert D
2013-05-01
The surrounding thermal environment has a direct influence on the well-being of an animal. However, few studies have investigated the microclimatic conditions that result from outdoor zoo enclosure designs and whether this affects where animals choose to spend time. Two African lions (Panthera leo) and two Siberian/Amur tigers (Panthera tigris altaica) were observed for a total of 18 full days during the summer and fall of 2009. Their activities and locations were recorded to the nearest minute of each test day. Simultaneous on-site microclimate measurements were taken of air temperature, relative humidity, solar radiation, and wind. Observations indicated that the locations where the animals chose to spend time were influenced by the microclimatic conditions. All subjects spent more time in the shade on their sunny warm days than on other days and differed from one another in their choice of shade source on all days. Temperature-comparable sunny and cloudy days showed a greater use of sun on the cloudy days. Species-specific differences between the lions (whose native habitat is hot) and the tigers (whose native habitat is temperate with cold winters) were observed with the tigers displaying more cooling behaviors than the lions in terms of solar radiation input and evaporative heat loss. The tigers were also more active than the lions. The results of this study provide new insight into how lions and tigers respond to microclimatic conditions in a captive environment.
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Effects of summer microclimates on behavior of lions and tigers in zoos
NASA Astrophysics Data System (ADS)
Young, Tory; Finegan, Esther; Brown, Robert D.
2013-05-01
The surrounding thermal environment has a direct influence on the well-being of an animal. However, few studies have investigated the microclimatic conditions that result from outdoor zoo enclosure designs and whether this affects where animals choose to spend time. Two African lions ( Panthera leo) and two Siberian/Amur tigers ( Panthera tigris altaica) were observed for a total of 18 full days during the summer and fall of 2009. Their activities and locations were recorded to the nearest minute of each test day. Simultaneous on-site microclimate measurements were taken of air temperature, relative humidity, solar radiation, and wind. Observations indicated that the locations where the animals chose to spend time were influenced by the microclimatic conditions. All subjects spent more time in the shade on their sunny warm days than on other days and differed from one another in their choice of shade source on all days. Temperature-comparable sunny and cloudy days showed a greater use of sun on the cloudy days. Species-specific differences between the lions (whose native habitat is hot) and the tigers (whose native habitat is temperate with cold winters) were observed with the tigers displaying more cooling behaviors than the lions in terms of solar radiation input and evaporative heat loss. The tigers were also more active than the lions. The results of this study provide new insight into how lions and tigers respond to microclimatic conditions in a captive environment.
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Microclimate and the zoonotic cycle of tick-borne encephalitis virus in Switzerland.
Burri, C; Bastic, V; Maeder, G; Patalas, E; Gern, L
2011-05-01
The focal distribution of tick-borne encephalitis virus (TBEV; Flaviviridae, Flavivirus) appears to depend mainly on cofeeding transmission between infected Ixodes ricinus L. nymphs and uninfected larvae. To better understand the role of cofeeding ticks in the transmission of TBEV, we investigated tick infestation of rodents and the influence of microclimate on the seasonality of questing I. ricinus ticks. A 3-yr study was carried out at four sites, including two confirmed TBEV foci. Free-living ticks and rodents were collected monthly, and microclimatic data were recorded. A decrease in questing nymph density was observed in 2007, associated with low relative humidity and high temperatures in spring. One site, Thun, did not show this decrease, probably because of microclimatic conditions in spring that favored the questing nymph population. During the same year, the proportion of rodents carrying cofeeding ticks was lower at sites where the questing nymph density decreased, although the proportion of infested hosts was similar among years. TBEV was detected in 0.1% of questing ticks, and in 8.6 and 50.0% of larval ticks feeding on two rodents. TBEV was detected at all but one site, where the proportion of hosts with cofeeding ticks was the lowest. The proportion of hosts with cofeeding ticks seemed to be one of the factors that distinguished a TBEV focus from a non-TBEV focus. The enzootic cycle of TBEV might be disrupted when dry and hot springs occur during consecutive years.
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Runeman, Bo; Rybo, Göran; Forsgren-Brusk, Ulla; Larkö, Olle; Larsson, Peter; Faergemann, Jan
2005-01-01
The aim of the present study was to investigate if tight-fitting underwear (string panties) equipped with string panty liners affected the vulvar skin microenvironment differently to regular panties with standard panty liners. Thirty-two healthy women participated in a crossover study where temperature, humidity, surface pH and aerobic microflora were measured on vulvar skin. Vulvar skin temperature was 35.2 +/- 0.19 (mean +/- SEM) and 35.3 +/- 0.17 degrees C, respectively, for the two underwear systems. Mean humidity and mean skin surface pH at vulvar skin did not differ between the two systems. Barely noticeable differences were found for the aerobic microflora both at labium majus and at perineum. The mean total number of microorganisms in the two different panty liners was the same, 6.0 +/- 0.15 and 6.0 +/- 0.16, respectively (log CFU per panty liner). The differences in panty and panty liner design studied seem to have negligible impact on the vulvar skin microclimate, skin surface pH and aerobic microflora. No support was found for the assumption that a string panty system would result in higher contamination of vulvar skin by anorectal microflora.
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NASA Astrophysics Data System (ADS)
Bubier, J. L.; Arnkil, S.; Humphreys, E.; Juutinen, S.; Larmola, T.; Moore, T. R.
2015-12-01
Atmospheric nitrogen (N) deposition has led to nutrient enrichment in wetlands globally, affecting plant community composition, carbon (C) cycling, and microbial dynamics. Nutrient-limited boreal bogs are long-term sinks of carbon dioxide (CO2), but sources of methane (CH4), an important greenhouse gas. We fertilized Mer Bleue Bog, a Sphagnum moss and evergreen shrub-dominated ombrotrophic bog near Ottawa, Ontario, for 10-15 years with N as NO3 and NH4 at 5, 10 and 20 times ambient N deposition (0.6-0.8 g N m-2 y-1), with and without phosphorus (P) and potassium (K). Treatments were applied to triplicate plots (3 x 3 m) from May - August 2000-2015 and control plots received distilled water. We measured net ecosystem CO2 exchange (NEE), ecosystem photosynthesis and respiration, and CH4 flux with climate-controlled chambers; leaf-level CO2 exchange and biochemistry; substrate-induced respiration, CH4 production and consumption potentials with laboratory incubations; plant species composition and abundance; and microclimate (peat temperature, moisture, light interception). After 15 years, we have found that NEE has decreased, and CH4 emissions have increased, in the highest nutrient treatments owing to changes in vegetation, microtopography, and peat characteristics. Vegetation changes include a loss of Sphagnum moss and introduction of new deciduous species. Simulated atmospheric N deposition has not benefitted the photosynthetic apparatus of the dominant evergreen shrubs, but resulted in higher foliar respiration, contributing to a weaker ecosystem CO2 sink. Loss of moss has led to wetter near-surface substrate, higher rates of decomposition and CH4 emission, and a shift in microbial communities. Thus, elevated atmospheric deposition of nutrients may endanger C storage in peatlands through a complex suite of feedbacks and interactions among vegetation, microclimate, and microbial communities.
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Armstrong, Alona; Waldron, Susan; Whitaker, Jeanette; Ostle, Nicholas J
2014-01-01
Global energy demand is increasing as greenhouse gas driven climate change progresses, making renewable energy sources critical to future sustainable power provision. Land-based wind and solar electricity generation technologies are rapidly expanding, yet our understanding of their operational effects on biological carbon cycling in hosting ecosystems is limited. Wind turbines and photovoltaic panels can significantly change local ground-level climate by a magnitude that could affect the fundamental plant–soil processes that govern carbon dynamics. We believe that understanding the possible effects of changes in ground-level microclimates on these phenomena is crucial to reducing uncertainty of the true renewable energy carbon cost and to maximize beneficial effects. In this Opinions article, we examine the potential for the microclimatic effects of these land-based renewable energy sources to alter plant–soil carbon cycling, hypothesize likely effects and identify critical knowledge gaps for future carbon research. PMID:24132939
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Evans, Michelle V.; McClanahan, Taylor D.; Miazgowicz, Kerri L.; Tesla, Blanka
2017-01-01
Most statistical and mechanistic models used to predict mosquito-borne disease transmission incorporate climate drivers of disease transmission by utilizing environmental data collected at geographic scales that are potentially coarser than what mosquito populations may actually experience. Temperature and relative humidity can vary greatly between indoor and outdoor environments, and can be influenced strongly by variation in landscape features. In the Aedes albopictus system, we conducted a proof-of-concept study in the vicinity of the University of Georgia to explore the effects of fine-scale microclimate variation on mosquito life history and vectorial capacity (VC). We placed Ae. albopictus larvae in artificial pots distributed across three replicate sites within three different land uses–urban, suburban, and rural, which were characterized by high, intermediate, and low proportions of impervious surfaces. Data loggers were placed into each larval environment and in nearby vegetation to record daily variation in water and ambient temperature and relative humidity. The number of adults emerging from each pot and their body size and sex were recorded daily. We found mosquito microclimate to significantly vary across the season as well as with land use. Urban sites were in general warmer and less humid than suburban and rural sites, translating into decreased larval survival, smaller body sizes, and lower per capita growth rates of mosquitoes on urban sites. Dengue transmission potential was predicted to be higher in the summer than the fall. Additionally, the effects of land use on dengue transmission potential varied by season. Warm summers resulted in a higher predicted VC on the cooler, rural sites, while warmer, urban sites had a higher predicted VC during the cooler fall season. PMID:28558030
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Murdock, Courtney C; Evans, Michelle V; McClanahan, Taylor D; Miazgowicz, Kerri L; Tesla, Blanka
2017-05-01
Most statistical and mechanistic models used to predict mosquito-borne disease transmission incorporate climate drivers of disease transmission by utilizing environmental data collected at geographic scales that are potentially coarser than what mosquito populations may actually experience. Temperature and relative humidity can vary greatly between indoor and outdoor environments, and can be influenced strongly by variation in landscape features. In the Aedes albopictus system, we conducted a proof-of-concept study in the vicinity of the University of Georgia to explore the effects of fine-scale microclimate variation on mosquito life history and vectorial capacity (VC). We placed Ae. albopictus larvae in artificial pots distributed across three replicate sites within three different land uses-urban, suburban, and rural, which were characterized by high, intermediate, and low proportions of impervious surfaces. Data loggers were placed into each larval environment and in nearby vegetation to record daily variation in water and ambient temperature and relative humidity. The number of adults emerging from each pot and their body size and sex were recorded daily. We found mosquito microclimate to significantly vary across the season as well as with land use. Urban sites were in general warmer and less humid than suburban and rural sites, translating into decreased larval survival, smaller body sizes, and lower per capita growth rates of mosquitoes on urban sites. Dengue transmission potential was predicted to be higher in the summer than the fall. Additionally, the effects of land use on dengue transmission potential varied by season. Warm summers resulted in a higher predicted VC on the cooler, rural sites, while warmer, urban sites had a higher predicted VC during the cooler fall season.
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Microclimate influence on mineral and metabolic profiles of grape berries.
Pereira, G E; Gaudillere, J-P; Pieri, P; Hilbert, G; Maucourt, M; Deborde, C; Moing, A; Rolin, D
2006-09-06
The grape berry microclimate is known to influence berry quality. The effects of the light exposure of grape berry clusters on the composition of berry tissues were studied on the "Merlot" variety grown in a vineyard in Bordeaux, France. The light exposure of the fruiting zone was modified using different intensities of leaf removal, cluster position relative to azimuth, and berry position in the cluster. Light exposures were identified and classified by in situ measurements of berry temperatures. Berries were sampled at maturity (>19 Brix) for determination of skin and/or pulp chemical and metabolic profiles based on (1) chemical and physicochemical measurement of minerals (N, P, K, Ca, Mg), (2) untargeted 1H NMR metabolic fingerprints, and HPLC targeted analyses of (3) amino acids and (4) phenolics. Each profile defined by partial least-square discriminant analysis allowed us to discriminate berries from different light exposure. Discriminant compounds between shaded and light-exposed berries were quercetin-3-glucoside, kaempferol-3-glucoside, myricetin-3-glucoside, and isorhamnetin-3-glucoside for the phenolics, histidine, valine, GABA, alanine, and arginine for the amino acids, and malate for the organic acids. Capacities of the different profiling techniques to discriminate berries were compared. Although the proportion of explained variance from the 1H NMR fingerprint was lower compared to that of chemical measurements, NMR spectroscopy allowed us to identify lit and shaded berries. Light exposure of berries increased the skin and pulp flavonols, histidine and valine contents, and reduced the organic acids, GABA, and alanine contents. All the targeted and nontargeted analytical data sets used made it possible to discriminate sun-exposed and shaded berries. The skin phenolics pattern was the most discriminating and allowed us to sort sun from shade berries. These metabolite classes can be used to qualify berries collected in an undetermined environment. The
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[Hygienic aspects of the microclimate in intensive management of rabbits].
Fiser, A
1994-01-01
In a four-row cowshed adapted for rabbit housing, air temperatures and humidity were recorded ambulantly and instrumentally, air flow rate, cooling variable, gas content in the air, microbial contamination of air and dust deposition were determined ambulantly in the years 1991-1992 and in January to April 1993. The values of ambulant measurings show that at the outside temperature -0.5 degrees C to -5.0 degrees C the microclimate quality decreases particularly with respect to the drop of air temperature in the cowshed below 10.0 degrees C, to the increase in cooling variable up to the value 53.17 mW/cm2 and to the increase in NH3 and CO2 content to 50 ppm and/or 0.45 vol.% in absolute maximum values. In these circumstances, the average determined values of both gases are higher than the standard prescription. At outside temperatures above 27.0 degrees C the average relative air humidity in the cowshed made 69.20% for the average temperature of 25.0 degrees C. To avoid the water vapor tension exceeding the limit in the cowshed air above the value 14.1 mm Hg, when sultry atmosphere sets in, the average relative air humidity should be maximally 59.0%. Hence the cowshed was found to be insufficiently ventilated at high outside temperatures above 27.0 degrees C, and it is recommended to increase the ventilator performance and at the same time to reduce water evaporation from catchpit surfaces when urine output of rabbits is excessive as a result of the increased water intake. Temperature and air humidity readings confirmed the need of heating source installation when the outside temperatures drop below 0.0 degrees C. Evaluation of air microbial contamination showed high counts of molds and particularly of micrococci in comparison with the ambience of a cage facility for piglet raising at a repopulation station with strict hygienic regime. Microbial picture of dust deposition was positively influenced by longitudinal aerosol disinfection of the air in the cowshed.
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NASA Astrophysics Data System (ADS)
Li, Xia; Mitra, Chandana; Dong, Li; Yang, Qichun
2018-02-01
To explore potential climatic consequences of land cover change in the Kolkata Metropolitan Development area, we projected microclimate conditions in this area using the Weather Research and Forecasting (WRF) model driven by future land use scenarios. Specifically, we considered two land conversion scenarios including an urbanization scenario that all the wetlands and croplands would be converted to built-up areas, and an irrigation expansion scenario in which all wetlands and dry croplands would be replaced by irrigated croplands. Results indicated that land use and land cover (LULC) change would dramatically increase regional temperature in this area under the urbanization scenario, but expanded irrigation tended to have a cooling effect. In the urbanization scenario, precipitation center tended to move eastward and lead to increased rainfall in eastern parts of this region. Increased irrigation stimulated rainfall in central and eastern areas but reduced rainfall in southwestern and northwestern parts of the study area. This study also demonstrated that urbanization significantly reduced latent heat fluxes and albedo of land surface; while increased sensible heat flux changes following urbanization suggested that developed land surfaces mainly acted as heat sources. In this study, climate change projection not only predicts future spatiotemporal patterns of multiple climate factors, but also provides valuable insights into policy making related to land use management, water resource management, and agriculture management to adapt and mitigate future climate changes in this populous region.
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Voelker, C; Alsaad, H
2018-05-01
This study aims to develop an approach to couple a computational fluid dynamics (CFD) solver to the University of California, Berkeley (UCB) thermal comfort model to accurately evaluate thermal comfort. The coupling was made using an iterative JavaScript to automatically transfer data for each individual segment of the human body back and forth between the CFD solver and the UCB model until reaching convergence defined by a stopping criterion. The location from which data are transferred to the UCB model was determined using a new approach based on the temperature difference between subsequent points on the temperature profile curve in the vicinity of the body surface. This approach was used because the microclimate surrounding the human body differs in thickness depending on the body segment and the surrounding environment. To accurately simulate the thermal environment, the numerical model was validated beforehand using experimental data collected in a climate chamber equipped with a thermal manikin. Furthermore, an example of the practical implementations of this coupling is reported in this paper through radiant floor cooling simulation cases, in which overall and local thermal sensation and comfort were investigated using the coupled UCB model. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
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Armstrong, Alona; Waldron, Susan; Whitaker, Jeanette; Ostle, Nicholas J
2014-06-01
Global energy demand is increasing as greenhouse gas driven climate change progresses, making renewable energy sources critical to future sustainable power provision. Land-based wind and solar electricity generation technologies are rapidly expanding, yet our understanding of their operational effects on biological carbon cycling in hosting ecosystems is limited. Wind turbines and photovoltaic panels can significantly change local ground-level climate by a magnitude that could affect the fundamental plant-soil processes that govern carbon dynamics. We believe that understanding the possible effects of changes in ground-level microclimates on these phenomena is crucial to reducing uncertainty of the true renewable energy carbon cost and to maximize beneficial effects. In this Opinions article, we examine the potential for the microclimatic effects of these land-based renewable energy sources to alter plant-soil carbon cycling, hypothesize likely effects and identify critical knowledge gaps for future carbon research. © 2013 John Wiley & Sons Ltd.
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Thomas, Shalu; Ravishankaran, Sangamithra; Justin, N A Johnson Amala; Asokan, Aswin; Kalsingh, T Maria Jusler; Mathai, Manu Thomas; Valecha, Neena; Montgomery, Jacqui; Thomas, Matthew B; Eapen, Alex
2018-05-16
Environmental factors such as temperature, relative humidity and their daily variation influence a range of mosquito life history traits and hence, malaria transmission. The standard way of characterizing environmental factors with meteorological station data need not be the actual microclimates experienced by mosquitoes within local transmission settings. A year-long study was conducted in Chennai, India to characterize local temperature and relative humidity (RH). Data loggers (Hobos) were placed in a range of probable indoor and outdoor resting sites of Anopheles stephensi. Recordings were taken hourly to estimate mean temperature and RH, together with daily temperature range (DTR) and daily relative humidity range. The temperature data were used to explore the predicted variation in extrinsic incubation period (EIP) of Plasmodium falciparum and Plasmodium vivax between microhabitats and across the year. Mean daily temperatures within the indoor settings were significantly warmer than those recorded outdoors. DTR in indoor environments was observed to be modest and ranged from 2 to 6 °C. Differences in EIP between microhabitats were most notable during the hottest summer months of April-June, with parasite development predicted to be impaired for tiled houses and overhead tanks. Overall, the prevailing warm and stable conditions suggest rapid parasite development rate regardless of where mosquitoes might rest. Taking account of seasonal and local environmental variation, the predicted EIP of P. falciparum varied from a minimum of 9.1 days to a maximum of 15.3 days, while the EIP of P. vivax varied from 8.0 to 24.3 days. This study provides a detailed picture of the actual microclimates experienced by mosquitoes in an urban slum malaria setting. The data indicate differences between microhabitats that could impact mosquito and parasite life history traits. The predicted effects for EIP are often relatively subtle, but variation between minimum and maximum
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Thornton, J
2000-07-01
To determine if the microclimate is detrimental to horses during international air transportation in an enclosed container. On each of two 12 h and two 24 h flights three horses were transported in an enclosed container designed to prevent exposure to insect vectors. Heart rates were monitored throughout and blood samples were collected periodically. Air in the container was sampled for bacteria and fungal spores and the temperature and relative humidity were recorded inside and outside the container periodically during the flight. On the two 12 h flights similar observations were made on three horses transported in regular open containers, which were used as controls. Heart rates during the flights reflected any agitation of the horses. Agitation was only mild and generally associated with take-off and landing. There were no changes in haematological or blood biochemical values that suggested any detrimental effects of the flights. The temperature in the Airstable was relatively constant during each flight (means ranged from 18.7 to 23.4 degrees C) and was significantly warmer than in the cargo hold (range 13.9 to 18.3 degrees C). Relative humidity fluctuated more widely and reflected the ambient humidity during airport stops. The numbers of bacteria and fungal spores in the Airstable air varied during the flights but were of no apparent significance to the horses' health. The Airstable proved a convenient means to transport horses on international flights and caused no discernible ill effects on the horses studied.
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Li, Xia; Mitra, Chandana; Dong, Li; ...
2017-02-02
In order to explore potential climatic consequences of land cover change in the Kolkata Metropolitan Development area, we projected microclimate conditions in this area using the Weather Research and Forecasting (WRF) model driven by future land use scenarios. Specifically, we considered two land conversion scenarios including an urbanization scenario that all the wetlands and croplands would be converted to built-up areas, and an irrigation expansion scenario in which all wetlands and dry croplands would be replaced by irrigated croplands. Our results indicated that land use and land cover (LULC) change would dramatically increase regional temperature in this area under themore » urbanization scenario, but expanded irrigation tended to have a cooling effect. In the urbanization scenario, precipitation center tended to move eastward and lead to increased rainfall in eastern parts of this region. Increased irrigation stimulated rainfall in central and eastern areas but reduced rainfall in southwestern and northwestern parts of the study area. Our study also demonstrated that urbanization significantly reduced latent heat fluxes and albedo of land surface; while increased sensible heat flux changes following urbanization suggested that developed land surfaces mainly acted as heat sources. In this study, climate change projection not only predicts future spatiotemporal patterns of multiple climate factors, but also provides valuable insights into policy making related to land use management, water resource management, and agriculture management to adapt and mitigate future climate changes in this populous region.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Xia; Mitra, Chandana; Dong, Li
In order to explore potential climatic consequences of land cover change in the Kolkata Metropolitan Development area, we projected microclimate conditions in this area using the Weather Research and Forecasting (WRF) model driven by future land use scenarios. Specifically, we considered two land conversion scenarios including an urbanization scenario that all the wetlands and croplands would be converted to built-up areas, and an irrigation expansion scenario in which all wetlands and dry croplands would be replaced by irrigated croplands. Our results indicated that land use and land cover (LULC) change would dramatically increase regional temperature in this area under themore » urbanization scenario, but expanded irrigation tended to have a cooling effect. In the urbanization scenario, precipitation center tended to move eastward and lead to increased rainfall in eastern parts of this region. Increased irrigation stimulated rainfall in central and eastern areas but reduced rainfall in southwestern and northwestern parts of the study area. Our study also demonstrated that urbanization significantly reduced latent heat fluxes and albedo of land surface; while increased sensible heat flux changes following urbanization suggested that developed land surfaces mainly acted as heat sources. In this study, climate change projection not only predicts future spatiotemporal patterns of multiple climate factors, but also provides valuable insights into policy making related to land use management, water resource management, and agriculture management to adapt and mitigate future climate changes in this populous region.« less
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NASA Astrophysics Data System (ADS)
Song, Uhram; Mun, Saeromi; Ho, Chang-Hoi; Lee, Eun Ju
2012-06-01
The possible consequences of global warming on plant communities and ecosystems have wide-ranging ramifications. We examined how environmental change affects plant growth as a function of the variations in the microclimate along an urban-suburban climate gradient for two allergy-inducing, invasive plants, Humulus japonicus and Ambrosia artemisiifolia var. elatior. The environmental factors and plant growth responses were measured at two urban sites (Gangbuk and Seongbuk) and two suburban sites (Goyang and Incheon) around Seoul, South Korea. The mean temperatures and CO2 concentrations differed significantly between the urban (14.8 °C and 439 ppm CO2) and suburban (13.0 °C and 427 ppm CO2) sites. The soil moisture and nitrogen contents of the suburban sites were higher than those at the urban sites, especially for the Goyang site. The two invasive plants showed significantly higher biomasses and nitrogen contents at the two urban sites. We conducted experiments in a greenhouse to confirm the responses of the plants to increased temperatures, and we found consistently higher growth rates under conditions of higher temperatures. Because we controlled the other factors, the better performance of the two invasive plants appears to be primarily attributable to their responses to temperature. Our study demonstrates that even small temperature changes in the environment can confer significant competitive advantages to invasive species. As habitats become urbanized and warmer, these invasive plants should be able to displace native species, which will adversely affect people living in these areas.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Xia; Mitra, Chandana; Dong, Li
To explore potential climatic consequences of land cover change in the Kolkata Metropolitan Development area, we projected microclimate conditions in this area using the Weather Research and Forecasting (WRF) model driven by future land use scenarios. Specifically, we considered two land conversion scenarios including an urbanization scenario that all the wetlands and croplands would be converted to built-up areas, and an irrigation expansion scenario in which all wetlands and dry croplands would be replaced by irrigated croplands. Results indicated that land use and land cover (LULC) change would dramatically increase regional temperature in this area under the urbanization scenario, butmore » expanded irrigation tended to have a cooling effect. In the urbanization scenario, precipitation center tended to move eastward and lead to increased rainfall in eastern parts of this region. Increased irrigation stimulated rainfall in central and eastern areas but reduced rainfall in southwestern and northwestern parts of the study area. This study also demonstrated that urbanization significantly reduced latent heat fluxes and albedo of land surface; while increased sensible heat flux changes following urbanization suggested that developed land surfaces mainly acted as heat sources. In this study, climate change projection not only predicts future spatiotemporal patterns of multiple climate factors, but also provides valuable insights into policy making related to land use management, water resource management, and agriculture management to adapt and mitigate future climate changes in this populous region. (C) 2017 Elsevier Ltd. All rights reserved.« less
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Song, Uhram; Mun, Saeromi; Ho, Chang-Hoi; Lee, Eun Ju
2012-06-01
The possible consequences of global warming on plant communities and ecosystems have wide-ranging ramifications. We examined how environmental change affects plant growth as a function of the variations in the microclimate along an urban-suburban climate gradient for two allergy-inducing, invasive plants, Humulus japonicus and Ambrosia artemisiifolia var. elatior. The environmental factors and plant growth responses were measured at two urban sites (Gangbuk and Seongbuk) and two suburban sites (Goyang and Incheon) around Seoul, South Korea. The mean temperatures and CO(2) concentrations differed significantly between the urban (14.8 °C and 439 ppm CO(2)) and suburban (13.0 °C and 427 ppm CO(2)) sites. The soil moisture and nitrogen contents of the suburban sites were higher than those at the urban sites, especially for the Goyang site. The two invasive plants showed significantly higher biomasses and nitrogen contents at the two urban sites. We conducted experiments in a greenhouse to confirm the responses of the plants to increased temperatures, and we found consistently higher growth rates under conditions of higher temperatures. Because we controlled the other factors, the better performance of the two invasive plants appears to be primarily attributable to their responses to temperature. Our study demonstrates that even small temperature changes in the environment can confer significant competitive advantages to invasive species. As habitats become urbanized and warmer, these invasive plants should be able to displace native species, which will adversely affect people living in these areas.
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Variations in household microclimate affect outdoor-biting behaviour of malaria vectors
Ngowo, Halfan S.; Kaindoa, Emmanuel Wilson; Matthiopoulos, Jason; Ferguson, Heather M.; Okumu, Fredros O.
2017-01-01
Background: Mosquito behaviours including the degree to which they bite inside houses or outside is a crucial determinant of human exposure to malaria. Whilst seasonality in mosquito vector abundance is well documented, much less is known about the impact of climate on mosquito behaviour. We investigated how variations in household microclimate affect outdoor-biting by malaria vectors, Anopheles arabiensis and Anopheles funestus. Methods: Mosquitoes were sampled indoors and outdoors weekly using human landing catches at eight households in four villages in south-eastern Tanzania, resulting in 616 trap-nights over 12 months. Daily temperature, relative humidity and rainfall were recorded. Generalized additive mixed models (GAMMs) were used to test associations between mosquito abundance and the microclimatic conditions. Generalized linear mixed models (GLMMs) were used to investigate the influence of microclimatic conditions on the tendency of vectors to bite outdoors (proportion of outdoor biting). Results: An. arabiensis abundance peaked during high rainfall months (February-May), whilst An. funestus density remained stable into the dry season (May-August) . Across the range of observed household temperatures, a rise of 1 ºC marginally increased nightly An. arabiensis abundance (~11%), but more prominently increased An. funestus abundance (~66%). The abundance of An. arabiensis and An. funestus showed strong positive associations with time-lagged rainfall (2-3 and 3-4 weeks before sampling). The degree of outdoor biting in An. arabiensis was significantly associated with the relative temperature difference between indoor and outdoor environments, with exophily increasing as temperature inside houses became relatively warmer. The exophily of An. funestus did not vary with temperature differences. Conclusions: This study demonstrates that malaria vector An. arabiensis shifts the location of its biting from indoors to outdoors in association with relative
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Evaluation of microbiological air quality and of microclimate in university classrooms.
Grisoli, Pietro; Rodolfi, Marinella; Chiara, Tiziana; Zonta, Laura Attinia; Dacarro, Cesare
2012-07-01
particular case, to intervene on other aspects that influence the microclimate.
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Hayden, Mary H; Uejio, Christopher K; Walker, Kathleen; Ramberg, Frank; Moreno, Rafael; Rosales, Cecilia; Gameros, Mercedes; Mearns, Linda O; Zielinski-Gutierrez, Emily; Janes, Craig R
2010-08-01
This study examined the association of human and environmental factors with the presence of Aedes aegypti, the vector for dengue fever and yellow fever viruses, in a desert region in the southwest United States and northwest Mexico. Sixty-eight sites were longitudinally surveyed along the United States-Mexico border in Tucson, AZ, Nogales, AZ, and Nogales, Sonora during a 3-year period. Aedes aegypti presence or absence at each site was measured three times per year using standard oviposition traps. Maximum and minimum temperature and relative humidity were measured hourly at each site. Field inventories were conducted to measure human housing factors potentially affecting mosquito presence, such as the use of air-conditioning and evaporative coolers, outdoor vegetation cover, and access to piped water. The results showed that Ae. aegypti presence was highly variable across space and time. Aedes aegypti presence was positively associated with highly vegetated areas. Other significant variables included microclimatic differences and access to piped water. This study demonstrates the importance of microclimate and human factors in predicting Ae. aegypti distribution in an arid environment.
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NASA Astrophysics Data System (ADS)
Rankine, C. J.; Sánchez-Azofeifa, G.
2011-12-01
In the face of unprecedented global change driven by anthropogenic pressure on natural systems it has become imperative to monitor and better understand potential shifts in ecosystem functioning and services from local to global scales. The utilization of automated sensors technologies offers numerous advantages over traditional on-site ecosystem surveying techniques and, as a result, sensor networks are becoming a powerful tool in environmental monitoring programs. Tropical forests, renowned for their biodiversity, are important regulators of land-atmosphere fluxes yet the seasonally dry tropical forests, which account for 40% of forested ecosystems in the American tropics, have been severely degraded over the past several decades and not much is known of their capacity to recover. With less than 1% of these forests protected, our ability to monitor the dynamics and quantify changes in the remaining primary and recovering secondary tropical dry forests is vital to understanding mechanisms of ecosystem stress responses and climate feedback with respect to annual productivity and desertification processes in the tropics. The remote sensing component of the Tropi-Dry: Human and Biophysical Dimensions of Tropical Dry Forests in the Americas research network supports a network of long-term tropical ecosystem monitoring platforms which focus on the dynamics of seasonally dry tropical forests in the Americas. With over 25 sensor station deployments operating across a latitudinal gradient in Mexico, Costa Rica, Brazil, and Argentina continuously collecting hyper-temporal sensory input based on standardized deployment parameters, this monitoring system is unique among tropical environments. Technologies used in the network include optical canopy phenology towers, understory wireless sensing networks, above and below ground microclimate stations, and digital cameras. Sensory data streams are uploaded to a cyber-infrastructure initiative, denominated Enviro-Net°, for data
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Dupoué, Andréaz; Stahlschmidt, Zachary R; Michaud, Bruno; Lourdais, Olivier
2015-05-15
Animals typically respond to environmental variation by adjusting their physiology, behavior, or both. Ectothermic animals are particularly sensitive to microclimatic conditions and behaviorally thermoregulate to optimize physiological performance. Yet, thermoregulation can be costly and may obligate a physiological tradeoff with water loss. Presumably, this tradeoff intensifies when animals undergo necessary life-history events (e.g., pregnancy or digestion) that impose significant behavioral and physiological changes, including shifts in behavioral thermoregulation and increased metabolic rate. Thus, behavioral responses, such as modified microclimatic preferences, may help mitigate the physiological tradeoff between thermoregulation and water loss. Herein, we examined the influence of major physiological states (specifically, pregnancy, ecdysis, and digestion) on evaporative water loss and on behavioral adjustments in a viviparous snake, Vipera aspis. First, we used open-flow respirometry to measure the effects of physiological states and microclimatic conditions (temperature and humidity) on the rate of total evaporative water loss (TEWL) and metabolic rate (rate of O2 consumption, V˙O2). Then, we experimentally tested the influence of physiological state on microclimate selection. We found that energy-demanding physiological states were associated with i) an increased rate of TEWL and V˙O2 compared to control states and ii) a slight preference (statistically marginal) for both warm and humid conditions compared to controls, suggesting a state-specificity in behavioral response. Overall our results underline the impact of physiological state on water loss and demonstrate the potential for behavior to mitigate the physiological tradeoff between thermoregulation and water balance. Copyright © 2015 Elsevier Inc. All rights reserved.
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García-Diego, Fernando-Juan; Verticchio, Elena; Beltrán, Pedro; Siani, Anna Maria
2016-08-15
Monitoring temperature and relative humidity of the environment to which artefacts are exposed is fundamental in preventive conservation studies. The common approach in setting measuring instruments is the choice of a high sampling rate to detect short fluctuations and increase the accuracy of statistical analysis. However, in recent cultural heritage standards the evaluation of variability is based on moving average and short fluctuations and therefore massive acquisition of data in slowly-changing indoor environments could end up being redundant. In this research, the sampling frequency to set a datalogger in a museum room and inside a microclimate frame is investigated by comparing the outcomes obtained from datasheets associated with different sampling conditions. Thermo-hygrometric data collected in the Sorolla room of the Pio V Museum of Valencia (Spain) were used and the widely consulted recommendations issued in UNI 10829:1999 and EN 15757:2010 standards and in the American Society of Heating, Air-Conditioning and Refrigerating Engineers (ASHRAE) guidelines were applied. Hourly sampling proved effective in obtaining highly reliable results. Furthermore, it was found that in some instances daily means of data sampled every hour can lead to the same conclusions as those of high frequency. This allows us to improve data logging design and manageability of the resulting datasheets.
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García-Diego, Fernando-Juan; Verticchio, Elena; Beltrán, Pedro; Siani, Anna Maria
2016-01-01
Monitoring temperature and relative humidity of the environment to which artefacts are exposed is fundamental in preventive conservation studies. The common approach in setting measuring instruments is the choice of a high sampling rate to detect short fluctuations and increase the accuracy of statistical analysis. However, in recent cultural heritage standards the evaluation of variability is based on moving average and short fluctuations and therefore massive acquisition of data in slowly-changing indoor environments could end up being redundant. In this research, the sampling frequency to set a datalogger in a museum room and inside a microclimate frame is investigated by comparing the outcomes obtained from datasheets associated with different sampling conditions. Thermo-hygrometric data collected in the Sorolla room of the Pio V Museum of Valencia (Spain) were used and the widely consulted recommendations issued in UNI 10829:1999 and EN 15757:2010 standards and in the American Society of Heating, Air-Conditioning and Refrigerating Engineers (ASHRAE) guidelines were applied. Hourly sampling proved effective in obtaining highly reliable results. Furthermore, it was found that in some instances daily means of data sampled every hour can lead to the same conclusions as those of high frequency. This allows us to improve data logging design and manageability of the resulting datasheets. PMID:27537886
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NASA Astrophysics Data System (ADS)
Horemans, B.; Schalm, O.; De Wael, K.; Cardell, C.; Van Grieken, R.
2012-07-01
The world famous Alhambra monument in Granada, Southern Spain, listed as UNESCO world cultural heritage since 1984, represents probably the most beautiful example of Islamic art and architecture from the Middle Ages in Europe. It is visited by ca. 2 million people annually. Granada is situated in a natural basin, surrounded by mountains with altitudes up to 3500 m. Due to this topography and the prevailing low wind speeds, pollution-derived and especially traffic-derived particulate matter often accumulates in the urban air. In order to evaluate the potential conservation risks from the surrounding air, the atmospheric composition in the Alhambra monument was evaluated. Indoor temperature and relative humidity fluctuations were evaluated for their potential degenerative effects. Furthermore, the atmospheric composition in the Alhambra was analyzed in terms of inorganic gases (NO2, SO2, O3, and NH3) and black carbon. It was found that the open architecture protected the indoor environments from developing a potentially harmful microclimate, such as the build-up of humidity resulting from the huge number of daily tourists. On the downside, the strong ventilation made the indoor air hardly different from outdoor air, as characterized by strong diurnal temperature and relative humidity gradients and high traffic-derived pollutant levels.
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Microclimates of l'Aven d'Orgnac and other French limestone caves (Chauvet, Esparros, Marsoulas)
NASA Astrophysics Data System (ADS)
Bourges, F.; Genthon, P.; Mangin, A.; D'Hulst, D.
2006-10-01
We assess the aerodynamics of the atmosphere in some limestone caves using a 5-year monitoring of the Aven d'Orgnac system, shorter thermal vertical profiling experiments, and comparison with the time series from other French caves. In the first rooms, located under the Aven opening, our records indicate, for each year, a succession of a summer regime characterized by stable parameters (except for the perturbations introduced by tourist visits) and a winter regime, in which the inner air temperature drops and is highly correlated with that outside. Atmospheric composition suggests that during the winter regime the cave is ventilated by the outside air. We show that the onset of the winter regime is governed by a thermo-convective instability involving the inflow of the outside cold and dense air. Atmospheric temperature and composition allow us to follow the stepwise progression of the winter regime toward the adjacent rooms.In the Salle Plane (SP), a far room of the Orgnac-Issirac karstic system, in which the winter regime has never been observed, the air temperature is extremely homogeneous and steady, and is characterized by a half-daily signal of amplitude less than 0.03 °C, which is correlated with the derivative of pressure versus time. This correlation, which is also observed in various other confined caves, may be explained by pressure-induced temperature changes relaxed in less than 1 h by thermal exchanges with a large volume of rock whose temperature is assumed to be constant.The various microclimates of karstic cave systems should be taken into account for the conservation of the caves open to tourists and for the interpretation of growth laminae of speleothems.
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Influence of season and microclimate on fertility of dairy cows in a hot-arid environment
NASA Astrophysics Data System (ADS)
Ray, D. E.; Jassim, A. H.; Armstrong, D. V.; Wiersma, F.; Schuh, J. D.
1992-09-01
Records were obtained over a 3 year period from six Holstein dairy farms of 300 to 500 cows each in the Phoenix, Ariz. area. Dairies were selected on the basis of similar management practices, herd size, milk production and facilities (with the exception of cooling systems). Microclimatic modifications (two dairies each) were shade only (approximately 3.7 m2/cow), evaporative-cooled shades and low-pressure water foggers under the shades. Data were categorized by season of calving (spring, Feb. May; summer, June Sept.; and fall, Oct. Jan.). Traits evaluated were calving interval, days open and services/conception. Calving interval was shortest for cows calving in the spring (378 days), intermediate in fall (382 days) and longest in summer (396 days). Similar seasonal trends were observed for days open (103, 103 and 119 days, respectively) and services/conception (1.54, 1.81 and 1.93, respectively). All differences between spring and summer were significant ( P < 0.05). Calving interval and days open were less for evaporative-cooled groups (374 and 98 days, respectively), with no difference between shade only and foggers (391 and 392 days, 112 and 116 days, respectively). Services/conception were similar for all groups (1.72 to 1.79). A significant interaction between microclimate and season for services/conception could be interpreted as (i) smaller season differences for evaporative-cooled groups than for shade or foggers, or (ii) a change in the ranking of control and fogger groups during summer versus fall. Evaporative cooling was more effective than fogging for reducing the detrimental effects of seasonal high temperatures on fertility.
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NASA Astrophysics Data System (ADS)
Ma, J.; Dmochowski, J. E.
2016-12-01
Southern California's Santa Monica Mountain coastal range hosts chaparral and coastal sage scrub ecosystems with distinct, local variations in their fire regime, microclimate, and proximity to urbanization. The high biodiversity combined with ongoing human impact make monitoring the ecological and land cover changes crucial. Due to their extensive, continuous temporal coverage and high spatial resolution, Landsat data are well suited to this purpose. Landsat-derived time-series NDVI data and classification maps have been compiled to identify regions most sensitive to change in order to determine the effects of fire regime, geography, and urbanization on vegetative changes; and assess the encroachment of non-native grasses. Spatial analysis of the classification maps identified the factors more conducive to land-cover changes as native shrubs were replaced with non-native grasses. Understanding the dynamics that govern semi-arid resilience, overall greening, and fire regime is important to predicting and managing large scale ecosystem changes as pressures from global climate change and urbanization intensify.
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NASA Astrophysics Data System (ADS)
Chen, Chun; Ho, Lih-Der
2017-04-01
This study reports a continuous microclimate monitoring carried out in the Gorilla Cave (Kaohsiung, Taiwan) between December 2015 and December 2016. This limestone cave is located in the Mt. Shoushan, which is mainly composed of limestone and mudstone. This study tried to assess the recreational impacts to the microclimate of the cave by monitoring the CO2, temperature, humidity and barometric pressure. Two monitoring stations were set up respectively at the front part (station A) and the end of the cave (station B). We also set up an auto-operated time-lapse camera at the entrance of the cave to record the numbers of tourists, and their entering time and the durations in cave. As carbon dioxide in the limestone cave may have negative impact to both speleothems and visitors, our presentation focuses on the variations of CO2 concentration in the Gorilla Cave. Daily and seasonal fluctuations of CO2 concentration were observed. The fluctuations are closely related with the temperature outside the cave. In summer, when the temperature outside the cave maintained at 30。C, fluctuations of CO2 concentration in the cave will become chaotic. The CO2 concentration would fluctuate around 1000ppm most of the day, but it would be relatively low ( 500ppm) during the noon. In winter, when temperature outside the cave maintained below 25゜C, the fluctuation of CO2 concentration in cave presented a steady state ( 400-500 ppm). Only at the noon, the temperature outside the cave rose above 25 ゜C, the CO2 concentration inside the cave would increase. There were 1,517 tourists entered the cave during the monitoring period. The average number of visitors in a group is 13, and each group averagely stayed for 15 minutes. Over half of the visitors (776 tourists) entered the cave in December, due to lower humidity, drier in the cave and less dripping water in winter. After tourists entered the cave, the CO2 concentration value of station A rose instantly. However, most tourists stayed
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Influence of season and microclimate on fertility of dairy cows in a hot-arid environment.
Ray, D E; Jassim, A H; Armstrong, D V; Wiersma, F; Schuh, J D
1992-08-01
Records were obtained over a 3 year period from six Holstein dairy farms of 300 to 500 cows each in the Phoenix, Ariz. area. Dairies were selected on the basis of similar management practices, herd size, milk production and facilities (with the exception of cooling systems). Microclimatic modifications (two dairies each) were shade only (approximately 3.7 m2/cow), evaporative-cooled shades and low-pressure water foggers under the shades. Data were categorized by season of calving (spring, Feb.-May; summer, June-Sept.; and fall, Oct.-Jan.). Traits evaluated were calving interval, days open and services/conception. Calving interval was shortest for cows calving in the spring (378 days), intermediate in fall (382 days) and longest in summer (396 days). Similar seasonal trends were observed for days open (103, 103 and 119 days, respectively) and services/conception (1.54, 1.81 and 1.93, respectively). All differences between spring and summer were significant (P less than 0.05). Calving interval and days open were less for evaporative-cooled groups (374 and 98 days, respectively), with no difference between shade only and foggers (391 and 392 days, 112 and 116 days, respectively). Services/conception were similar for all groups (1.72 to 1.79). A significant interaction between microclimate and season for services/conception could be interpreted as (i) smaller season differences for evaporative-cooled groups than for shade or foggers, or (ii) a change in the ranking of control and fogger groups during summer versus fall. Evaporative cooling was more effective than fogging for reducing the detrimental effects of seasonal high temperatures on fertility.
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Cator, Lauren J; Thomas, Shalu; Paaijmans, Krijn P; Ravishankaran, Sangamithra; Justin, Johnson A; Mathai, Manu T; Read, Andrew F; Thomas, Matthew B; Eapen, Alex
2013-03-02
Environmental temperature is an important driver of malaria transmission dynamics. Both the parasite and vector are sensitive to mean ambient temperatures and daily temperature variation. To understand transmission ecology, therefore, it is important to determine the range of microclimatic temperatures experienced by malaria vectors in the field. A pilot study was conducted in the Indian city of Chennai to determine the temperature variation in urban microclimates and characterize the thermal ecology of the local transmission setting. Temperatures were measured in a range of probable indoor and outdoor resting habitats of Anopheles stephensi in two urban slum malaria sites. Mean temperatures and daily temperature fluctuations in local transmission sites were compared with standard temperature measures from the local weather station. The biological implications of the different temperatures were explored using temperature-dependent parasite development models to provide estimates of the extrinsic incubation period (EIP) of Plasmodium vivax and Plasmodium falciparum. Mean daily temperatures within the urban transmission sites were generally warmer than those recorded at the local weather station. The main reason was that night-time temperatures were higher (and hence diurnal temperature ranges smaller) in the urban settings. Mean temperatures and temperature variation also differed between specific resting sites within the transmission environments. Most differences were of the order of 1-3°C but were sufficient to lead to important variation in predicted EIPs and hence, variation in estimates of transmission intensity. Standard estimates of environmental temperature derived from local weather stations do not necessarily provide realistic measures of temperatures within actual transmission environments. Even the small differences in mean temperatures or diurnal temperature ranges reported in this study can lead to large variations in key mosquito and/or parasite
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NASA Astrophysics Data System (ADS)
Khrit, N. G.; Alghoul, M. A.; Sopian, K.; Lahimer, A. A.; Elayeb, O. K.
2017-11-01
Assessing outdoor human thermal comfort and urban climate quality require experimental investigation of microclimatic conditions and their variations in open urban spaces. For this, it is essential to provide quantitative information on air temperature, humidity, wind velocity and mean radiant temperature. These parameters can be quantified directly except mean radiant temperature (Tmrt). The most accurate method to quantify Tmrt is integral radiation measurements (3-D shortwave and long-wave) which require using expensive radiometer instruments. To overcome this limitation the well-known globe thermometer method was suggested to calculate Tmrt. The aim of this study was to assess the possibility of using indoor globe thermometer method in predicting outdoor mean radiant temperature under Malaysia tropical microclimate. Globe thermometer method using small and large sizes of black-painted copper globes (50mm, 150mm) were used to estimate Tmrt and compare it with the reference Tmrt estimated by integral radiation method. The results revealed that the globe thermometer method considerably overestimated Tmrt during the middle of the day and slightly underestimated it in the morning and late evening. The difference between the two methods was obvious when the amount of incoming solar radiation was high. The results also showed that the effect of globe size on the estimated Tmrt is mostly small. Though, the estimated Tmrt by the small globe showed a relatively large amount of scattering caused by rapid changes in radiation and wind speed.
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Assessing the Performance of Large Scale Green Roofs and Their Impact on the Urban Microclimate
NASA Astrophysics Data System (ADS)
Smalls-Mantey, L.; Foti, R.; Montalto, F. A.
2015-12-01
In ultra-urban environments green roofs offer a feasible solution to add green infrastructure (GI) in neighborhoods where space is limited. Green roofs offer the typical advantages of urban GI such as stormwater reduction and management while providing direct benefits to the buildings on which they are installed through thermal protection and mitigation of temperature fluctuations. At 6.8 acres, the Jacob K. Javits Convention Center (JJCC) in New York City, hosts the second largest green roof in the United States. Since its installation in August 2013, the Sustainable Water Resource (SWRE) Laboratory at Drexel University has monitored the climate on and around the green roof by means of four weather stations situated on various roof and ground locations. Using two years of fine scale climatic data collected at the JJCC, this study explores the energy balance of a large scale green roof system. Temperature, radiation, evapotranspiration and wind profiles pre- and post- installation of the JJCC green roof were analyzed and compared across monitored locations, with the goal of identifying the impact of the green roof on the building and urban micro-climate. Our findings indicate that the presence of the green roof, not only altered the climatic conditions above the JJCC, but also had a measurable impact on the climatic profile of the areas immediately surrounding it. Furthermore, as a result of the mitigation of roof temperature fluctuations and of the cooling provided during warmer months, an improvement of the building thermal efficiency was contextually observed. Such findings support the installation of GI as an effective practice in urban settings and important in the discussion of key issues including energy conservation measures, carbon emission reductions and the mitigation of urban heat islands.
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Wang, Cheng; Pang, Xue-Yong; Bao, Wei-Kai
2010-03-01
Taking a dense spruce pure plantation as test object and simulating the formation of natural forest gap, this paper studied the effects of low intensity thinning by gap creation on the ground temperature, ground humidity, and nutrient contents in different soil layers of the plantation. In the first year of gap creation, the mean diurnal temperature in the gap across the growth season (May - September) increased, while the mean diurnal humidity decreased. The soil organic matter (SOM) and NH4(+) -N contents in O-horizon (humus layer) increased by 19.62% and 283.85%, and the dissolved organic carbon (DOC) and NO3(-) -N contents decreased by 77.86% and 23.60%, respectively. The SOM, total nitrogen (TN), and NO3(-) -N contents in 0-10 cm soil layer increased by 45.77%, 37.14%, and 75.11%, and the NH4(+) -N, DOC, and total phosphorus (TP) contents decreased by 48.56%, 33.33%, and 13.11%, respectively. All the results suggested that low intensity thinning by gap creation could rapidly improve the ground microclimate of the plantation, and consequently, promote the soil microbial activity and mineralization processes in O-horizon, the release of soil nutrients, and the restoration of soil fertility.
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Water relations and microclimate around the upper limit of a cloud forest in Maui, Hawai'i.
Gotsch, Sybil G; Crausbay, Shelley D; Giambelluca, Thomas W; Weintraub, Alexis E; Longman, Ryan J; Asbjornsen, Heidi; Hotchkiss, Sara C; Dawson, Todd E
2014-07-01
The goal of this study was to determine the effects of atmospheric demand on both plant water relations and daily whole-tree water balance across the upper limit of a cloud forest at the mean base height of the trade wind inversion in the tropical trade wind belt. We measured the microclimate and water relations (sap flow, water potential, stomatal conductance, pressure-volume relations) of Metrosideros polymorpha Gaudich. var. polymorpha in three habitats bracketing the cloud forest's upper limit in Hawai'i to understand the role of water relations in determining ecotone position. The subalpine shrubland site, located 100 m above the cloud forest boundary, had the highest vapor pressure deficit, the least amount of rainfall and the highest levels of nighttime transpiration (EN) of all three sites. In the shrubland site, on average, 29% of daily whole-tree transpiration occurred at night, while on the driest day of the study 50% of total daily transpiration occurred at night. While EN occurred in the cloud forest habitat, the proportion of total daily transpiration that occurred at night was much lower (4%). The average leaf water potential (Ψleaf) was above the water potential at the turgor loss point (ΨTLP) on both sides of the ecotone due to strong stomatal regulation. While stomatal closure maintained a high Ψleaf, the minimum leaf water potential (Ψleafmin) was close to ΨTLP, indicating that drier conditions may cause drought stress in these habitats and may be an important driver of current landscape patterns in stand density. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
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Characterizing microclimate in urban malaria transmission settings: a case study from Chennai, India
2013-01-01
Background Environmental temperature is an important driver of malaria transmission dynamics. Both the parasite and vector are sensitive to mean ambient temperatures and daily temperature variation. To understand transmission ecology, therefore, it is important to determine the range of microclimatic temperatures experienced by malaria vectors in the field. Methods A pilot study was conducted in the Indian city of Chennai to determine the temperature variation in urban microclimates and characterize the thermal ecology of the local transmission setting. Temperatures were measured in a range of probable indoor and outdoor resting habitats of Anopheles stephensi in two urban slum malaria sites. Mean temperatures and daily temperature fluctuations in local transmission sites were compared with standard temperature measures from the local weather station. The biological implications of the different temperatures were explored using temperature-dependent parasite development models to provide estimates of the extrinsic incubation period (EIP) of Plasmodium vivax and Plasmodium falciparum. Results Mean daily temperatures within the urban transmission sites were generally warmer than those recorded at the local weather station. The main reason was that night-time temperatures were higher (and hence diurnal temperature ranges smaller) in the urban settings. Mean temperatures and temperature variation also differed between specific resting sites within the transmission environments. Most differences were of the order of 1-3°C but were sufficient to lead to important variation in predicted EIPs and hence, variation in estimates of transmission intensity. Conclusions Standard estimates of environmental temperature derived from local weather stations do not necessarily provide realistic measures of temperatures within actual transmission environments. Even the small differences in mean temperatures or diurnal temperature ranges reported in this study can lead to large
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Johnson, Joseph S; Lacki, Michael J
2014-01-01
A growing number of mammal species are recognized as heterothermic, capable of maintaining a high-core body temperature or entering a state of metabolic suppression known as torpor. Small mammals can achieve large energetic savings when torpid, but they are also subject to ecological costs. Studying torpor use in an ecological and physiological context can help elucidate relative costs and benefits of torpor to different groups within a population. We measured skin temperatures of 46 adult Rafinesque's big-eared bats (Corynorhinus rafinesquii) to evaluate thermoregulatory strategies of a heterothermic small mammal during the reproductive season. We compared daily average and minimum skin temperatures as well as the frequency, duration, and depth of torpor bouts of sex and reproductive classes of bats inhabiting day-roosts with different thermal characteristics. We evaluated roosts with microclimates colder (caves) and warmer (buildings) than ambient air temperatures, as well as roosts with intermediate conditions (trees and rock crevices). Using Akaike's information criterion (AIC), we found that different statistical models best predicted various characteristics of torpor bouts. While the type of day-roost best predicted the average number of torpor bouts that bats used each day, current weather variables best predicted daily average and minimum skin temperatures of bats, and reproductive condition best predicted average torpor bout depth and the average amount of time spent torpid each day by bats. Finding that different models best explain varying aspects of heterothermy illustrates the importance of torpor to both reproductive and nonreproductive small mammals and emphasizes the multifaceted nature of heterothermy and the need to collect data on numerous heterothermic response variables within an ecophysiological context. PMID:24558571
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Grundel, R.; Pavlovic, N.B.
2007-01-01
Determination of which aspects of habitat quality and habitat spatial arrangement best account for variation in a species’ distribution can guide management for organisms such as the Karner blue butterfly (Lycaeides melissa samuelis), a federally endangered subspecies inhabiting savannas of Midwest and Eastern United States. We examined the extent to which three sets of predictors, (1) larval host plant (Lupinus perennis, wild lupine) availability, (2) characteristics of the matrix surrounding host plant patches, and (3) factors affecting a patch’s thermal environment, accounted for variation in lupine patch use by Karner blues at Indiana Dunes National Lakeshore, Indiana and Fort McCoy, Wisconsin, USA. Each predictor set accounted for 7–13% of variation in patch occupancy by Karner blues at both sites and in larval feeding activity among patches at Indiana Dunes. Patch area, an indicator of host plant availability, was an exception, accounting for 30% of variation in patch occupancy at Indiana Dunes. Spatially structured patterns of patch use across the landscape accounted for 9–16% of variation in patch use and explained more variation in larval feeding activity than did spatial autocorrelation between neighboring patches. Because of this broader spatial trend across sites, a given management action may be more effective in promoting patch use in some portions of the landscape than in others. Spatial trend, resource availability, matrix quality, and microclimate, in general, accounted for similar amounts of variation in patch use and each should be incorporated into habitat management planning for the Karner blue butterfly.
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Royles, Jessica; Amesbury, Matthew J; Roland, Thomas P; Jones, Glyn D; Convey, Peter; Griffiths, Howard; Hodgson, Dominic A; Charman, Dan J
2016-07-01
The stable isotope compositions of moss tissue water (δ(2)H and δ(18)O) and cellulose (δ(13)C and δ(18)O), and testate amoebae populations were sampled from 61 contemporary surface samples along a 600-km latitudinal gradient of the Antarctic Peninsula (AP) to provide a spatial record of environmental change. The isotopic composition of moss tissue water represented an annually integrated precipitation signal with the expected isotopic depletion with increasing latitude. There was a weak, but significant, relationship between cellulose δ(18)O and latitude, with predicted source water inputs isotopically enriched compared to measured precipitation. Cellulose δ(13)C values were dependent on moss species and water content, and may reflect site exposure to strong winds. Testate amoebae assemblages were characterised by low concentrations and taxonomic diversity, with Corythion dubium and Microcorycia radiata types the most cosmopolitan taxa. The similarity between the intra- and inter-site ranges measured in all proxies suggests that microclimate and micro-topographical conditions around the moss surface were important determinants of proxy values. Isotope and testate amoebae analyses have proven value as palaeoclimatic, temporal proxies of climate change, whereas this study demonstrates that variations in isotopic and amoeboid proxies between microsites can be beyond the bounds of the current spatial variability in AP climate.
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NASA Astrophysics Data System (ADS)
Naot, O.; Mahrer, Y.
1991-08-01
A numerical two-dimensional model based on higher-order closure assumptions is developed to simulate the horizontal microclimate distribution over an irrigated field in arid surroundings. The model considers heat, mass, momentum, and radiative fluxes in the soil-plant-atmosphere system. Its vertical domain extends through the whole planetary boundary layer. The model requires temporal solar and atmospheric radiation data, as well as temporal boundary conditions for wind-speed, air temperature, and humidity. These boundary conditions are specified by an auxiliary mesoscale model and are incorporated in the microscale model by a nudging method. Vegetation parameters (canopy height, leaf-angle orientation distribution, leaf-area index, photometric properties, root-density distribution), soil texture, and soil-hydraulic and photometric properties are considered. The model is tested using meteorological data obtained in a drip-irrigated cotton field located in an extremely arid area, where strong fetch effects are expected. Four masts located 50 m before the leading edge of the field and 10, 30, and 100 m inward from the leading edge are used to measure various meteorological parameters and their horizontal and vertical gradients. Calculated values of air and soil temperatures, wind-speed, net radiation and soil, latent, and sensible heat fluxes agreed well with measurements. Large horizontal gradients of air temperature are both observed and measured within the canopy in the first 40 m of the leading edge. Rate of evapotranspiration at both the upwind and the downwind edges of the field are higher by more than 15% of the midfield value. Model calculations show that a stable thermal stratification is maintained above the whole field for 24 h. The aerodynamic and thermal internal boundary layer (IBL) growth is proportional to the square root of the fetch. This is also the observed rate of growth of the thermal IBL over a cool sea surface.
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NASA Astrophysics Data System (ADS)
Herbst, M.; Wittich, K. P.; Meinert, T.; Namyslo, J.; Frühauf, C.; Falge, E.
2017-12-01
The agrometeorological soil and crop water model developed by the German Meteorological Service a few decades ago and has recently been updated and refined in order to serve as a tool to assess the future options, risks and opportunities for agriculture in a changing climate. The core of the model consists of a SVAT scheme that calculates the different evaporation components of agricultural ecosystems, their energy balance and canopy microclimate and the water storage in several soil layers. In contrast to the widely used FAO schemes to calculate the crop water relations, the new model distinguishes between the productive and unproductive fractions of evapotranspiration and thus produces a more realistic account of water stress and irrigation demand. Furthermore, the model represents the water relations of the root zone in greater detail and accounts specifically for the water extraction from various depths. Infiltration rate and capillary rise are simulated, too, as well as leaf wetness duration following rain, irrigation or dewfall, and temperature and humidity within the canopy and the soil. As a consequence of these additional features, the model serves also as a robust basis for more specific predictions of, e.g., soil trafficability or phytopathological aspects. Here we present an overview about the model and show some examples where we test its suitability for forecasts of irrigation demands, for predictions of actual evaporation rates and soil water status of specific crops using various climate projections and for a coupling to biogeochemical models describing e.g. ammonia emissions, nitrate losses, crop yield etc. Challenges and opportunities for an extended application of the model are discussed and perspectives for its use as a decision support tool developed, particularly with respect to risk assessments of potential agricultural yield reductions due to drought, heat, frost, stagnant moisture and other environmental stress factors.
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Fabrication and Testing of Tapered Electro-spray Nozzles
2012-09-01
4.2 Microclimate Issues .......................................................................................................20 5. Summary and...requirement, while using very low flow rates per nozzle to obtain small combustor geometries. 4.2 Microclimate One of the challenges with this...off the Taylor-cone. To determine if there is an influence of microclimate , the evaporation rate was calculated from the Langmuir equation 1, using
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Dadgar, S; Lee, E S; Leer, T L V; Burlinguette, N; Classen, H L; Crowe, T G; Shand, P J
2010-05-01
This study investigated the effect of microclimate temperature during preslaughter transportation on chicken meat quality. Ninety broilers per load of 2,900 were monitored individually during 3 to 4 h of preslaughter transport in an actively ventilated trailer. Six transport test runs were conducted at average ambient temperatures of -27, -22, -17, -5, +4, and +11 degrees C. Birds were classified into 4 groups based upon the temperatures recorded in their immediate surroundings as follows: -16 to 0, 0 to 10, 10 to 20, and 20 to 30 degrees C. Internal body temperatures of the birds were recorded using Thermocron DS1922L iButtons. Birds were slaughtered in a commercial facility and meat quality of the chilled carcasses was evaluated by determination of pH, color, drip loss, thaw loss, cook loss, shear force, water-binding capacity, and pellet cook yield of the pectoralis major muscle. The breast meat from birds exposed to temperatures below 0 degrees C showed a significantly higher (P < 0.05) ultimate pH. Breast meat from birds exposed to temperatures below 0 degrees C showed significantly higher (P < 0.05) ultimate pH, a* value, water-binding capacity, and pellet cook yield and a significantly lower L* compared with breast meat of birds exposed to temperatures above 0 degrees C. The average core body temperatures were significantly lower (P < 0.05) during transport for birds exposed to temperatures below 0 degrees C compared with those exposed to temperatures between 0 and 10 degrees C. The latter birds had significantly lower (P < 0.05) core body temperatures compared with those exposed to temperatures above 10 degrees C. Thaw loss was significantly higher (P < 0.05) for breast meat of birds exposed to temperatures above 20 degrees C during transportation. There was no significant trend for b* value, drip loss, cook loss, or shear values based on environment temperature immediately surrounding the birds. Exposure to temperatures below 0 degrees C increased the
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Solar Maps Development: How the Maps Were Made | Geospatial Data Science |
10% of a true measured value within the grid cell. Due to terrain effects and other microclimate effects and other microclimate influences, the local cloud cover can vary significantly even within a approximately 10% of a true measured value within the grid cell. Due to terrain effects and other microclimate
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Hozumi, Satoshi; Inagaki, Terumi
2010-01-01
Polybia spinifex Richards (Hymenoptera: Vespidae) constructs mud nests characterized by a long slit-like entrance. The ventilation and thermal characteristics of the P. spinifex nest were investigated to determine whether the nest microclimate is automatically maintained due to the size of the entrance. In order to examine this hypothesis, a numerical simulation was employed to predict the effects of the entrance length. The calculations were performed with 3D-virtual models that simulated the P. spinifex nest conditions, and the reliability of the simulations was experimentally examined by using gypsum-model nests and a P. spinifex nest. The ventilation effect was determined by blowing air through the nest at 1-3 m/s (airflow conditions); the airspeed was found to be higher in models with a longer entrance. The ventilation rate was also higher in models with longer entrances, suggesting that the P. spinifex nest is automatically ventilated by natural winds. Next, the thermal effect was calculated under condition of direct sunlight. Under a calm condition (airflow, 0 m/s), thermal convection and a small temperature drop were observed in the case of models with a long entrance, whereas the ventilation and thermoregulation effects seemed small. Under airflow conditions, the temperature at the mid combs steeply dropped due to the convective airflow through the entrance at 1-2 m/s, and at 3 m/s, most of the heat was eliminated due to high thermal conductivity of the mud envelope, rather than convection.
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Wei, Quan-Shuai; Wang, Jing-Hua; Duan, Wen-Biao; Chen, Li-Xin; Wang, Ting; Han, Dong-Hui; Gu, Wei
2014-03-01
An investigation was conducted in a 2.25 hm2 plot of Pinus koraiensis-dominated broad-leaved mixed forest to study basic characteristics of 7 small gaps, 5 middle gaps, 3 large gaps and 7 closed stands within 38 pit and mound complexes caused by treefall in May 2012. From June to September 2012, the soil temperature, soil water content and relative humidity at five microsites (pit bottom, pit wall, mound top, mound face and undisturbed closed stands) were measured in six sunny days each month. The results showed that among the five microsites in every month, the mound top had the highest soil temperature and the lowest water content and relative humidity, and vice versa for the pit bottom. Mostly, the differences in the above indicators among the five microsites were significant. From June to September, the mean soil temperatures for all microsites at pit and mound complex in the various gaps and closed stands were in the order of large gap>middle gap >small gap>closed stand; but the soil water content ranked differently every month. In June, August and September, the mean relative humidities for all microsites in the various gaps and closed stands were in the order of closed stand>small gap>middle gap>large gap. Mostly, the differences in the above indicators between all microsites in the various gaps and closed stand were significant. The mean monthly soil temperature and relative humidity were highest in July, but lowest in September. The maximal mean monthly soil water content occurred in July and the minimal one in September for each microsite except the undisturbed closed stands, where the maximal mean monthly soil water content occurred in July. The variation of the microclimate at the pit and mound complex was mainly influenced by gap size, microsite, and time.
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2012-04-01
3.1 % RH. The microclimate within helicopters can be extreme, with elevated air temperatures, relative humidity, and solar load, with the greenhouse...experienced by helicopter pilots. Katz et al. (11) reported that an Air Warrior Chemical Protective ensemble with microclimate cooling was effective...study showed that a microclimate cooling system worn next to the skin could alleviate some of the thermal burden experienced (10). Banta and Braun
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2012-08-01
soldiers via microclimate cooling [13]. Unfortunately, a common method for direct cooling of the soldiers – surface cooling – can cause cutaneous...Intermittent, Regional Microclimate Cooling," Journal of Applied Physiology, vol. 94, pp. 1841-48, 2003. [18] L. A. Stephenson, C. R. Vernieuw, W...Leammukda and M. A. Kolka, "Skin Temperature Feedback Optimizes Microclimate Cooling," Aviation, Space and Environmental Medicine, vol. 78, pp. 377-382
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Feng, Jing; Duan, Wen-Biao; Chen, Li-Xin
2012-07-01
HOBO automatic weather stations were installed in the central parts and at the south, north, east, and west edges of large, medium, and small gaps in a Pinus koraiensis-dominated broadleaved mixed forest in Xiaoxing' anling Mountains to measure the air temperature, relative humidity, and photosynthetic photon flux density (PPFD) in these locations and the total radiation and precipitation in the gap centres from June to September 2010, taking the closed forest stand and open field as the controls. The differences in the microclimate between various size forest gaps and between the gap centers and their edges as well as the variations of the microclimatic factors over time were analyzed, and the effects of sunny and overcast days on the diurnal variations of the microclimatic factors within forest gaps were compared, aimed to offer basic data and practice reference for gap regeneration and sustainable management of Pinus koraiensis-dominated broadleaved mixed forest. The PPFD was decreased in the order of large gap, medium gap, and small gap. For the same gaps, the PPFD in gap centre was greater than that in gap edge. The mean monthly air temperature and total radiation in gap centres were declined in the sequence of July, June, August, and September, and the amplitudes of the two climatic factors were decreased in the order of open field, large gap, medium gap, small gap, and closed forest stand. The mean monthly relative humidity in gap centres dropped in the order of August, July, September, and June, and the amplitude of this climatic factor was decreased in the sequence of closed forest stand, small gap, medium gap, large gap, and open field. The total and monthly precipitations for the three different size gaps and open field during measurement period generally decreased in the order of open field, large gap, medium gap, small gap, and closed forest stand. In sunny days, the variations of PPFD, air temperature, and relative humidity were greater in large gap
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Reinhardt, Keith; Smith, William K
2008-11-01
The red spruce-Fraser fir ecosystem [Picea rubens Sarg.-Abies fraseri (Pursh) Poir.] of the southern Appalachian mountains, USA, is a temperate zone cloud forest immersed in clouds for 30-40% of a typical summer day, and experiencing immersion on about 65% of all days annually. We compared the microclimate, photosynthetic gas exchange, and water relations of Fraser fir trees in open areas during cloud-immersed, low-cloud, or sunny periods. In contrast to sunny periods, cloud immersion reduced instantaneous sunlight irradiance by 10-50%, and midday atmospheric vapor pressure deficit (VPD) was 85% lower. Needle surfaces were wet for up to 16 h per day during cloud-immersed days compared to <1 h for clear days. Shoot-level light-saturated photosynthesis (A (sat)) on both cloud-immersed (16.0 micromol m(-2) s(-1)) and low-cloud (17.9 micromol m(-2) s(-1)) days was greater than A (sat) on sunny days (14.4 micromol m(-2) s(-1)). Daily mean A was lowest on cloud-immersed days due to reduced sunlight levels, while leaf conductance (g) was significantly higher, with a mean value of 0.30 mol m(-2) s(-1). These g values were greater than commonly reported for conifer tree species with needle-like leaves, and declined exponentially with increasing leaf-to-air VPD. Daily mean transpiration (E) on immersed days was 43 and 20% lower compared to sunny and low-cloud days, respectively. As a result, daily mean water use efficiency (A/E) was lowest on cloud-immersed days due to light limitation of A, and high humidity resulted in greater uncoupling of A from g. Thus, substantial differences in photosynthetic CO2 uptake, and corresponding water relations, were strongly associated with cloud conditions that occur over substantial periods of the summer growth season.
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NASA Astrophysics Data System (ADS)
Henshall, S. E.; Sadler, J. P.; Hannah, D. M.
2009-04-01
Exposed riverine sediments (ERS) are frequently inundated areas of relatively un-vegetated, fluvially deposited sediment (sand, silt, gravel and pebble). These habitats provide an important interface allowing the interaction of aquatic and terrestrial habitats and species. ERS are highly valuable for many rare and specialist invertebrates particularly beetles. Within an area of ERS, beetle species richness tends to be highest along the water's edge. This higher species richness may be linked to: (1) the availability of food items in the form of emerging and stranded aquatic invertebrates and (2) favourable physical microhabitat conditions in terms of temperature and moisture. This paper explores the role of microclimate and food availability by creating areas of ‘water's edge' habitat in the centre of a gravel bar. Typically these areas are drier, reach higher temperatures and devoid of emerging aquatic invertebrate prey. Four 2m x 2m experimental plots were created: one wet plot, one wet- fed plot, one dry-fed plot and one dry plot (control). These plots were each replicated on three separate areas of ERS. Sixty colour marked ERS specialist ground beetles (Bembidion atrocaeruleum) were released into each plot to monitor beetle persistence and movement on and between plots. The plots were maintained wet using a capillary pump system, and fed with dried blood worms for 30 days. Sediment temperature (0.05 m depth) was measured at 15 minute intervals and spot measurements of surface temperature were taken daily. A hand search was carried out on 25% of each plot after 7, 14, 21 and 30 days. Significant temperature differences were observed between the wet and dry sediment and air temperature. The wet plots on average were 1.8oC cooler than the dry plots and had a reduced temperature range. Both wet and dry sediments remained significantly warmer than air temperature. The wet and wet-fed plots yielded significantly greater numbers of beetles and marked beetles than
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Goldhawk, C; Crowe, T; Janzen, E; González, L A; Kastelic, J; Pajor, E; Schwartzkopf-Genswein, K S
2014-11-01
factors (P > 0.05). Despite association between indicators of calf welfare and microclimate, all cattle arrived in good condition and there was 0.96% treatment rate within the first 30 d after arrival. Management and auditing decisions related to transportation of feeder cattle should consider the relationship between animal-level and ambient conditions and conditions before transportation. Under the commercial conditions of the current study, the transportation process did not appear to cause distress according to the dimensions of animal welfare that were assessed.
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NASA Astrophysics Data System (ADS)
Tan, Elcin; Onol, Baris; Acar, Merve; Biyik, Gokay; Unal, Yurdanur S.
2013-04-01
The main purpose of this research is to provide information on the change of temperature and humidity fields after the development of a new reservoir in the southeastern part of Turkey. It is believed that pistachio and pomegranates production rate might decrease due to a change of the microclimate of the Southern Anatolian Irrigation Project Region (GAP) with an inclusion of a large water volume. Since temperature and humidity are the significant meteorological variables for growing of these products, their change with the inclusion of the reservoir is analyzed using the WRF model. Two summer years, 2000 and 2002, are studied to indicate the importance of warm and cold summer years, respectively. NCEP/NCAR Reanalysis dataset is used for setting up initial and boundary conditions for 27 km, 9km, 3km, and 1km nested domains. 1 km resolution run is performed using ndown option of the WRF Model for 4 months of these two years, from June to October. 5 different microphysics, atmospheric boundary layer, cumulus, and land use parameterization scheme combinations are analyzed to decide on the appropriate physics scheme combination in order to reduce the biases occurred due to steep topography of this domain of interest. After this decision, the WRF model is performed for both control case, i.e., without the inclusion of any water bodies; and wet case, i.e. with the inclusion of a water body. The preliminary results show that the difference between wet and control cases is about 1°C for 2m temperature; whereas 2m relative humidity change is about 3% from the monthly averages of the 4 months. Therefore, these results may indicate that the production of pistachio and pomegranates may not be affected from the inclusion of a reservoir to the southeastern part of Turkey.
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Healy, R.W.; DeVries, M.P.; Sturrock, Alex M.
1989-01-01
From July 1982 through June 1984, a study was made of the evapotranspiration and microclimate at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Vegetation at the site consists of mixed pasture grasses, primarily awnless brome (Bromus inermis) and red clover (Trifoleum pratense). Three methods were used to estimate evapotranspiration: (1) an energy budget with the Bowen ratio, (2) an aerodynamic profile, and (3) a soil-based water budget. For the aerodynamic-profile method, sensible-heat flux was estimated by a profile equation and evapotranspiration was then calculated as the residual in the energy-balance equation. Estimates by the energy-budget and aerodynamic-profile methods were computed from hourly data and then summed by days and months. Yearly estimates (for March through November) by these methods were in close agreement: 648 and 626 millimeters, respectively. Daily estimates reach a maximum of about 6 millimeters. The water-budget method produced only monthly estimates based on weekly or biweekly soil-moisture content measurements. The yearly evapotranspiration estimated by this method (which actually included only the months of April through October) was 655 millimeters. The March-through-November average for the three methods of 657 millimeters was equivalent to 70 percent of total precipitation. Continuous measurements were made of incoming and reflected shortwave radiation, incoming and emitted longwave radiation, net radiation, soil-heat flux, soil temperature, horizontal windspeed, and wet- and dry-bulb air temperature. Windspeed and air temperature were measured at heights of 0.5 and 2.0 meters (and also at 1.0 meter after September 1983). Soilmoisture content of the soil zone was measured with a gamma-attenuation gage. Annual precipitation (938 millimeters) and average temperature (10.8 degrees Celsius) at the Sheffield site were virtually identical to long-term averages from nearby National Weather Service
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Healy, R.W.; DeVries, M.P.; Sturrock, A.M.
1987-01-01
From July 1982 through June 1984, a study was made of the microclimate and evapotranspiration at a low-level radioactive-waste disposal site near Sheffield, Bureau County, Illinois. Vegetation at the site consists of mixed pasture grasses, primarily brome (Bromus inermis) and red clover (Trifoleum pratense). Three methods were used to estimate evapotranspiration: (1) an energy-budget with the Bowen ratio, (2) an aerodynamic-profile, and (3) a soil-based water-budget. For the aerodynamic-profile method, sensible-heat flux was estimated by a profile equation and evapotranspiration was then calculated as the residual in the energy-balance equation. Estimates by the energy-budget and aerodynamic-profile methods were computed from hourly data, then summed by days and months. Yearly estimates for March through November, by these methods, were quite close--648 and 626 millimeters, respectively. Daily estimates range up to a maximum of about 6 millimeters. The water-budget method produced only monthly estimates based on weekly or biweekly soil-moisture content measurements. The yearly evapotranspiration estimated by this method (which actually included only the months of April through October) was 655 millimeters. The March-through-November average for the three methods of 657 millimeters was equivalent to 70 percent of precipitation. Continuous measurements were made of incoming and reflected shortwave radiation, incoming and emitted longwave radiation, net radiation, soil-heat flux, soil temperature, horizontal windspeed, and wet- and dry-bulb air temperature. Windspeed and air temperature were measured at heights of 0.5 and 2.0 meters (and also at 1.0 meter after September 1983). Soil-moisture content of the soil zone was measured with a gamma-attenuation gage. Annual precipitation (938 millimeters) and average temperature (10.8 degrees Celsius) were virtually identical to long-term averages from nearby National Weather Service stations. Solar radiation averaged 65
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NASA Astrophysics Data System (ADS)
Reinhardt, K.; Castanha, C.; Germino, M. J.; Kueppers, L. M.
2011-12-01
The elevation limit of tree growth (alpine treeline) is considered to be constrained by environmental (i.e., thermal) and genetic (i.e., inability to adapt to climatic conditions) limitations to growth. Warming conditions due to climate change are predicted to cause upward shifts in the elevation of alpine treelines, through relief of cold-induced physiological limitations on seedling recruitment beyond current treeline boundaries. To determine how genetics and climate may interact to affect seedling establishment, we transplanted recently germinated seedlings from high- and low-elevation provenances (HI and LO, respectively) of Pinus flexilis in common gardens arrayed along an elevation and canopy gradient from subalpine forest into the alpine zone at Niwot Ridge, CO. We compared differences in microclimate and seedling ecophysiology among sites and between provenances. During the first summer of growth, frequently cloudy skies resulted in similar solar radiation incidence and air and soil temperatures among sites, despite nearly a 500 m-span in elevation across all sites. Preliminary findings suggest that survival of seedlings was similar between the lowest and highest elevations, with greater survival of LO (60%) compared to HI (40%) seedlings at each of these sites. Photosynthesis, carbon balance (photosynthesis/respiration), and conductance increased more than 2X with elevation for both provenances, and were 35-77% greater in LO seedlings compared to HI seedlings. There were no differences in dark-adapted chlorophyll fluorescence (Fv/Fm) among sites or between provenances. However, in a common-garden study at low elevation, we observed no differences in carbon or water relations between two naturally-germinated mitochondrial haplotypes of P. flexilis (of narrow and wide-ranging distributions). We did observe water-related thresholds on seedling carbon balance and survival that occurred when soil volumetric water content dropped below 10% and seedling water
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Abiotic vs. biotic influences on habitat selection of coexisting species: Climate change impacts?
Martin, T.E.
2001-01-01
Species are commonly segregated along gradients of microclimate and vegetation. I explore the question of whether segregation is the result of microhabitat partitioning (biotic effects) or choice of differing microclimates (abiotic effects). I explored this question for four ground-nesting bird species that are segregated along a microclimate and vegetation gradient in Arizona. Birds shifted position of their nests on the microhabitat and microclimate gradient in response to changing precipitation over nine years. Similarly, annual bird abundance varied with precipitation across 12 yr. Those shifts in abundance and nesting microhabitat with changing precipitation demonstrate the importance of abiotic influences on bird distributions and habitat choice. However, nest-site shifts and microhabitat use also appear to be influenced by interactions among coexisting species. Moreover, shifts in habitat use by all species caused nest predation (i.e., biotic) costs that increased with increasing distance along the microclimate gradient. These results indicate that abiotic and biotic costs can strongly interact to influence microhabitat choice and abundances of coexisting species. Global climate change impacts have been considered largely in terms of simple distributional shifts, but these results indicate that shifts can also increase biotic costs when species move into habitat types for which they are poorly adapted or that create new biotic interactions.
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Simulation of within-canopy radiation exchange
USDA-ARS?s Scientific Manuscript database
Radiation exchange at the surface plays a critical role in the surface energy balance, plant microclimate, and plant growth. The ability to simulate the surface energy balance and the microclimate within the plant canopy is contingent upon simulation of the surface radiation exchange. A validation a...
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Software Tools for Weed Seed Germination Modeling
USDA-ARS?s Scientific Manuscript database
The next generation of weed seed germination models will need to account for variable soil microclimate conditions. In order to predict this microclimate environment we have developed a suite of individual tools (models) that can be used in conjunction with the next generation of weed seed germinati...
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Habitat associations of species show consistent but weak responses to climate
Suggitt, Andrew J.; Stefanescu, Constantí; Páramo, Ferran; Oliver, Tom; Anderson, Barbara J.; Hill, Jane K.; Roy, David B.; Brereton, Tom; Thomas, Chris D.
2012-01-01
Different vegetation types can generate variation in microclimates at local scales, potentially buffering species from adverse climates. To determine if species could respond to such microclimates under climatic warming, we evaluated whether ectothermic species (butterflies) can exploit favourable microclimates and alter their use of different habitats in response to year-to-year variation in climate. In both relatively cold (Britain) and warm (Catalonia) regions of their geographical ranges, most species shifted into cooler, closed habitats (e.g. woodland) in hot years, and into warmer, open habitats (e.g. grassland) in cooler years. Additionally, three-quarters of species occurred in closed habitats more frequently in the warm region than in the cool region. Thus, species shift their local distributions and alter their habitat associations to exploit favourable microclimates, although the magnitude of the shift (approx. 1.3% of individuals from open to shade, per degree Celsius) is unlikely to buffer species from impacts of regional climate warming. PMID:22491762
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Range expansion through fragmented landscapes under a variable climate
Bennie, Jonathan; Hodgson, Jenny A; Lawson, Callum R; Holloway, Crispin TR; Roy, David B; Brereton, Tom; Thomas, Chris D; Wilson, Robert J
2013-01-01
Ecological responses to climate change may depend on complex patterns of variability in weather and local microclimate that overlay global increases in mean temperature. Here, we show that high-resolution temporal and spatial variability in temperature drives the dynamics of range expansion for an exemplar species, the butterfly Hesperia comma. Using fine-resolution (5 m) models of vegetation surface microclimate, we estimate the thermal suitability of 906 habitat patches at the species' range margin for 27 years. Population and metapopulation models that incorporate this dynamic microclimate surface improve predictions of observed annual changes to population density and patch occupancy dynamics during the species' range expansion from 1982 to 2009. Our findings reveal how fine-scale, short-term environmental variability drives rates and patterns of range expansion through spatially localised, intermittent episodes of expansion and contraction. Incorporating dynamic microclimates can thus improve models of species range shifts at spatial and temporal scales relevant to conservation interventions. PMID:23701124
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Duan, Wen-biao; Du, Shan; Chen, Li-xin; Wang, Li-xia; Wei, Quan-shuai; Zhao, Jian-hui
2013-08-01
Three representative forest gaps with pit-mound microsites formed by uprooted trees were selected within the 2.55 hm2 plot in a Pinus koraiensis-dominated broad-leaved mixed forest in Xiao Xing'an Mountains of Northeast China. The cleared land and closed stand were set up as the controls, and the PAR, air temperature and relative humidity in the centers of different size gaps and in mound top as well as the total radiation and precipitation in the gap centers were measured between July and September, 2011 by using multichannel automatic meteorological stations. The differences of the microclimate between the gap centers and mound top in different months were compared, and the monthly and diurnal variations of the microclimatic factors in the gap centers and in the mound top under typical weather conditions were analyzed. The results showed that the mean monthly PAR and air temperature in the three gaps of different sizes were in the order of large gap > medium gap > small gap, and the mean monthly relative humidity was in the order of small gap > medium gap > large gap. For the same size gap, the mean monthly PAR and air temperature were higher in the mound top than in the gap center, whereas the mean monthly relative humidity was higher in the gap center than in the mound top. Both the mean monthly total radiation and the mean monthly air temperature in the forest gaps and in the controls were in the order of July > August > September and of cleared land > large gap > medium gap > small gap > closed stand, while the mean monthly relative humidity was in the order of closed stand > small gap > medium gap > large gap > cleared land. The differences in the mean monthly relative humidity between closed stand and various gaps and between closed stand and cleared land reached significant level. The monthly precipitation from July to September decreased in the order of cleared land > large gap > medium gap > small gap > closed stand. Whether in sunny days or in overcast
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Spatial models reveal the microclimatic buffering capacity of old-growth forests
Sarah J. K. Frey; Adam S. Hadley; Sherri L. Johnson; Mark Schulze; Julia A. Jones; Matthew. G. Betts
2016-01-01
Climate change is predicted to cause widespread declines in biodiversity, but these predictions are derived from coarse-resolution climate models applied at global scales. Such models lack the capacity to incorporate microclimate variability, which is critical to biodiversity microrefugia. In forested montane regions, microclimate is thought to be influenced by...
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NASA Astrophysics Data System (ADS)
van de Ven, C.; Weiss, S. B.
2009-12-01
Most climate models are expressed at regional scales, with resolutions on the scales of kilometers. When used for ecological modeling, these climate models help explain only broad-scale trends, such as latitudinal and upslope migration of plants. However, more refined ecological models require down-scaled climate data at ecologically relevant spatial scales, and the goal of this presentation is to demonstrate robust downscaling methods. For example, in the White Mountains, eastern California, tree species, including bristlecone pine (Pinus longaeva) are seen moving not just upslope, but also sideways across aspects, and downslope into areas characterized by cold air drainage. Macroclimate in the White Mountains is semi-arid, residing in the rain shadow of the Sierra Nevada. Macroclimate is modified by mesoscale effects of mountain ranges, where climate becomes wetter and colder with elevation, the temperature decreasing according to the regionally and temporally-specific lapse rate. Local topography further modifies climate, where slope angle, aspect, and topographic position further impact the temperature at a given site. Finally, plants experience extremely localized microclimate, where surrounding vegetation provide differing degrees of shade. We measured and modeled topoclimate across the White Mountains using iButton Thermochron temperature data loggers during late summer in 2006 and 2008, and have documented effects of microclimatic temperature differences between sites in the open and shaded by shrubs. Starting with PRISM 800m data, we derived mesoscale lapse rates. Then, we calculated temperature differentials between each Thermochron and a long-term weather station in the middle of the range at Crooked Creek Valley. We modeled month-specific minimum temperature differentials by regressing the Thermochron-weather station minimum temperature differentials with various topographic parameters. Topographic position, the absolute value of topographic position
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Dawson, Russell D; Lawrie, Cheyenne C; O'Brien, Erin L
2005-07-01
Organisms are expected to balance energy allocation in such a way that fitness is maximized. While much research has focussed on allocation strategies of reproducing parents, in particular birds, relatively little attention has been paid to how nestlings allocate energy while in the nest. Nestling birds are faced with a trade-off between devoting energy to growth or to thermoregulation, and in altricial species it is likely that the thermal environment of the nest site influences the nature of this trade-off. Here, we experimentally investigate how altering the microclimate of nests affects the growth, size and survival, as well as cell-mediated immune (CMI) response, of nestling tree swallows (Tachycineta bicolor) in a temperate environment. We place air-activated heating pads in nests of swallows when young were between 4 days and 16 days of age, and compared performance of offspring to control nests. Our manipulation raised temperatures of heated nests by approximately 5 degrees C compared to control nests. Offspring in heated nests had enhanced survival while in the nest, and we also found that they were heavier and had longer ninth primary feathers at 16 days of age. In addition, heating nest boxes resulted in significantly faster growth of primaries, and there was a trend for growth rates of mass to also be higher in heated nests. There were no significant differences between heated and control nests in growth rate or size of tarsus at age 16 days, and we speculate that this lack of response to elevated nest temperatures may be due to growth of skeletal structures being limited by other factors such as calcium availability. We also found no difference between heated and control nests in CMI response. Nonetheless, our results show overall that increasing temperatures of nests has significant benefits that enhance the fitness of offspring. As provisioning rates to offspring did not differ between heated and control nests, we suspect that the beneficial effects
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Tropical forests are thermally buffered despite intensive selective logging.
Senior, Rebecca A; Hill, Jane K; Benedick, Suzan; Edwards, David P
2018-03-01
Tropical rainforests are subject to extensive degradation by commercial selective logging. Despite pervasive changes to forest structure, selectively logged forests represent vital refugia for global biodiversity. The ability of these forests to buffer temperature-sensitive species from climate warming will be an important determinant of their future conservation value, although this topic remains largely unexplored. Thermal buffering potential is broadly determined by: (i) the difference between the "macroclimate" (climate at a local scale, m to ha) and the "microclimate" (climate at a fine-scale, mm to m, that is distinct from the macroclimate); (ii) thermal stability of microclimates (e.g. variation in daily temperatures); and (iii) the availability of microclimates to organisms. We compared these metrics in undisturbed primary forest and intensively logged forest on Borneo, using thermal images to capture cool microclimates on the surface of the forest floor, and information from dataloggers placed inside deadwood, tree holes and leaf litter. Although major differences in forest structure remained 9-12 years after repeated selective logging, we found that logging activity had very little effect on thermal buffering, in terms of macroclimate and microclimate temperatures, and the overall availability of microclimates. For 1°C warming in the macroclimate, temperature inside deadwood, tree holes and leaf litter warmed slightly more in primary forest than in logged forest, but the effect amounted to <0.1°C difference between forest types. We therefore conclude that selectively logged forests are similar to primary forests in their potential for thermal buffering, and subsequent ability to retain temperature-sensitive species under climate change. Selectively logged forests can play a crucial role in the long-term maintenance of global biodiversity. © 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.
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Kück-Biere, U; von Engelhardt, W
1990-01-01
K+ concentrations were measured in vitro with K+ sensitive microelectrodes in the microclimate at the luminal cell surface of the colon of guinea pigs. The serosal K+ concentration was mostly 5.4 mmol/1, the mucosal K+ concentrations were changed (0, 5, 50, or 70 mmol/l). Under control conditions K+ concentrations in the microclimate of the proximal colon were also low (6-9 mmol/l) and rather independent from K+ concentrations in the bulk luminal solution. In the distal colon K+ concentrations in the microclimate increased from 3.7 mmol/l when no K+ was in the luminal solution, up to 22 mmol/l when the mucosal K+ concentrations was 70 mmol/l. Attempts to decrease K+ conductance of the apical membrane with Ba++, to impair K+ transport with ouabain and to increase the paracellular shunt with deoxycholic acid did not affect K+ concentrations in the microclimate of the proximal colon but decreased K+ concentrations in the distal colon. When valinomycin or triaminopyrimidine were added to the mucosal solution at high K+ concentrations in the luminal solutions the K+ concentration in the microclimate was raised. At low luminal K+ concentrations valinomycin had no effect, triaminopyrimidine significantly diminished K+ concentrations at the cell surface. Regional differences in paracellular shunt conductance and in the preepithelial diffusion barrier are thought to be responsible for the observed differences between the proximal and the distal colon. Obviously, however, further unknown mechanisms have to be involved. PMID:2108077
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Natural disturbance reduces disease risk in endangered rainforest frog populations
Roznik, Elizabeth A.; Sapsford, Sarah J.; Pike, David A.; Schwarzkopf, Lin; Alford, Ross A.
2015-01-01
Natural disturbances can drive disease dynamics in animal populations by altering the microclimates experienced by hosts and their pathogens. Many pathogens are highly sensitive to temperature and moisture, and therefore small changes in habitat structure can alter the microclimate in ways that increase or decrease infection prevalence and intensity in host populations. Here we show that a reduction of rainforest canopy cover caused by a severe tropical cyclone decreased the risk of endangered rainforest frogs (Litoria rheocola) becoming infected by a fungal pathogen (Batrachochytrium dendrobatidis). Reductions in canopy cover increased the temperatures and rates of evaporative water loss in frog microhabitats, which reduced B. dendrobatidis infection risk in frogs by an average of 11–28% in cyclone-damaged areas, relative to unaffected areas. Natural disturbances to the rainforest canopy can therefore provide an immediate benefit to frogs by altering the microclimate in ways that reduce infection risk. This could increase host survival and reduce the probability of epidemic disease outbreaks. For amphibian populations under immediate threat from this pathogen, targeted manipulation of canopy cover could increase the availability of warmer, drier microclimates and therefore tip the balance from host extinction to coexistence. PMID:26294048
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Natural disturbance reduces disease risk in endangered rainforest frog populations.
Roznik, Elizabeth A; Sapsford, Sarah J; Pike, David A; Schwarzkopf, Lin; Alford, Ross A
2015-08-21
Natural disturbances can drive disease dynamics in animal populations by altering the microclimates experienced by hosts and their pathogens. Many pathogens are highly sensitive to temperature and moisture, and therefore small changes in habitat structure can alter the microclimate in ways that increase or decrease infection prevalence and intensity in host populations. Here we show that a reduction of rainforest canopy cover caused by a severe tropical cyclone decreased the risk of endangered rainforest frogs (Litoria rheocola) becoming infected by a fungal pathogen (Batrachochytrium dendrobatidis). Reductions in canopy cover increased the temperatures and rates of evaporative water loss in frog microhabitats, which reduced B. dendrobatidis infection risk in frogs by an average of 11-28% in cyclone-damaged areas, relative to unaffected areas. Natural disturbances to the rainforest canopy can therefore provide an immediate benefit to frogs by altering the microclimate in ways that reduce infection risk. This could increase host survival and reduce the probability of epidemic disease outbreaks. For amphibian populations under immediate threat from this pathogen, targeted manipulation of canopy cover could increase the availability of warmer, drier microclimates and therefore tip the balance from host extinction to coexistence.
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Forest Microclimate Characteristics Review
2014-09-01
Co ns tr uc tio n En gi ne er in g R es ea rc h La bo ra to ry Rosemary Keane, Hannah Pitstick, Patrick J . Guertin, and Dick L. Gebhart...Annotated Bibliography Rosemary Keane, Hannah Pitstick, Patrick J . Guertin, and Dick L. Gebhart Construction Engineering Research Laboratory U.S. Army...alphabetical order by last name of the study’s first author. Anno - tations for these references are presented in Chapter 4. Hyperlinked page numbers and
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microclim: Global estimates of hourly microclimate based on long-term monthly climate averages
Kearney, Michael R; Isaac, Andrew P; Porter, Warren P
2014-01-01
The mechanistic links between climate and the environmental sensitivities of organisms occur through the microclimatic conditions that organisms experience. Here we present a dataset of gridded hourly estimates of typical microclimatic conditions (air temperature, wind speed, relative humidity, solar radiation, sky radiation and substrate temperatures from the surface to 1 m depth) at high resolution (~15 km) for the globe. The estimates are for the middle day of each month, based on long-term average macroclimates, and include six shade levels and three generic substrates (soil, rock and sand) per pixel. These data are suitable for deriving biophysical estimates of the heat, water and activity budgets of terrestrial organisms. PMID:25977764
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Microclim: Global estimates of hourly microclimate based on long-term monthly climate averages.
Kearney, Michael R; Isaac, Andrew P; Porter, Warren P
2014-01-01
The mechanistic links between climate and the environmental sensitivities of organisms occur through the microclimatic conditions that organisms experience. Here we present a dataset of gridded hourly estimates of typical microclimatic conditions (air temperature, wind speed, relative humidity, solar radiation, sky radiation and substrate temperatures from the surface to 1 m depth) at high resolution (~15 km) for the globe. The estimates are for the middle day of each month, based on long-term average macroclimates, and include six shade levels and three generic substrates (soil, rock and sand) per pixel. These data are suitable for deriving biophysical estimates of the heat, water and activity budgets of terrestrial organisms.
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Compensation and climate: Latitudinal variation in ecototherm response to environmental change
DOE Office of Scientific and Technical Information (OSTI.GOV)
Curtin, C.G.
1995-06-01
Thermal preference measured in a laboratory thermal gradient, and field body temperatures in a field enclosure, contrast the fundamental and realized thermal niches of ornate box turtles (Terrapene ornata) from northern, central, and southern locations. The relatively warmer thermal preference of southern turtles appears to result in lower body temperatures and relatively shorter activity periods. Variation in thermal constraints are input into computer simulations of ectotherm response to climate to assess latitudinal variation in turtle response to microclimate cooling (4{degrees} C), current climate (1970-1990), and climatic warming (3-5{degrees} C). Climatic warming is calculated to lead to a northward shift inmore » turtle range and distribution with increases in northern and declines in southern populations. Microclimate cooling is estimated to result in declines in northern areas and in the core of the box turtle range. The local changes in microclimate, such as can result from shifts in land-use, can be greater than those resulting from large scale changes in climate. Suggesting that land managers and conservation biologists need to focus greater attention on the impact of changes in within patch structure of plant associations and its implications for alteration of microclimate and species life history.« less
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Visco, Giovanni; Plattner, Susanne H; Fortini, Patrizia; Sammartino, Mariapia
2017-06-01
In the last decades, the very fast improvement of the analytical instrumentation has led to the possibility of quickly and easily getting a lot of data; in turn, the need of advanced statistical methods suitable to extract the full information furnished by instruments has increased. Such kind of data treatments is particularly important in any case of continuous monitoring of one or more parameters, so the microclimate monitoring is a typical example for this application. Microclimate control is essential in the conservation of Cultural Heritage (CH), but decisions on optimal conservation parameters cannot base only on existing norms that do not take into account the environment's history. Often CH has survived for many centuries in conditions that must be considered risky but also a stable state (equilibrium) resulting from a long adaptation process during which a more or less heavy damage occurred to the materials. Any successive change of microclimate parameters has interrupted this equilibrium conditions and has induced further damage to material until a new equilibrium is reached; dimension and frequency of changes are proportional to the expected damage. This thermodynamic consideration provides the background for a CH conservation project based on microclimate control and highlights the importance of environmental monitoring for the identification of equilibrium parameters to be maintained. In 2010, we monitored the microclimate of an important historical building in Rome, the Mamertino Carcer, before its opening to visitors. One year later, we repeated the monitoring in the presence of visitors, and here, we present a careful choice of multivariate data treatments adopted for an enough, simple and immediate evaluation of the microclimatic changes; this allows an easier understanding also for persons with not too deep scientific background, such as Superintendents and, in turn, really useful information to provide suggestions for a conservation project
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Woods, H Arthur; Dillon, Michael E; Pincebourde, Sylvain
2015-12-01
We analyze the effects of changing patterns of thermal availability, in space and time, on the performance of small ectotherms. We approach this problem by breaking it into a series of smaller steps, focusing on: (1) how macroclimates interact with living and nonliving objects in the environment to produce a mosaic of thermal microclimates and (2) how mobile ectotherms filter those microclimates into realized body temperatures by moving around in them. Although the first step (generation of mosaics) is conceptually straightforward, there still exists no general framework for predicting spatial and temporal patterns of microclimatic variation. We organize potential variation along three axes-the nature of the objects producing the microclimates (abiotic versus biotic), how microclimates translate macroclimatic variation (amplify versus buffer), and the temporal and spatial scales over which microclimatic conditions vary (long versus short). From this organization, we propose several general rules about patterns of microclimatic diversity. To examine the second step (behavioral sampling of locally available microclimates), we construct a set of models that simulate ectotherms moving on a thermal landscape according to simple sets of diffusion-based rules. The models explore the effects of both changes in body size (which affect the time scale over which organisms integrate operative body temperatures) and increases in the mean and variance of temperature on the thermal landscape. Collectively, the models indicate that both simple behavioral rules and interactions between body size and spatial patterns of thermal variation can profoundly affect the distribution of realized body temperatures experienced by ectotherms. These analyses emphasize the rich set of problems still to solve before arriving at a general, predictive theory of the biological consequences of climate change. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Valero, Miguel Ángel; Merello, Paloma; Navajas, Ángel Fernández; García-Diego, Fernando-Juan
2014-01-01
The Noheda archaeological site is unique and exceptional for its size, and the quality and conservation condition of the Roman mosaic pavement covering its urban pars. In 2008 a tent was installed as protection from rain and sun. Being of interest to characterise the microclimate of the remains, six probes with relative humidity and temperature sensors were installed in 2013 for this purpose. Microclimate monitoring allowed us to check relative humidity differences resulting from the groundwater level, as well as inner sensors reaching maximum temperatures higher than the outdoors ones as a consequence of the non-ventilated tent covering the archaeological site. Microclimatic conditions in the archaeological site were deemed detrimental for the conservation of the mosaics. Thus, in summer 2013, expanded clay and geotextile were installed over the mosaics as a corrective action. The outcomes of this study have proven the effectiveness of this solution to control temperature and relative humidity, helping to configure a more stable microclimate suitable for preservation of the mosaic. PMID:24445414
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Valero, Miguel Ángel; Merello, Paloma; Navajas, Ángel Fernández; García-Diego, Fernando-Juan
2014-01-17
The Noheda archaeological site is unique and exceptional for its size, and the quality and conservation condition of the Roman mosaic pavement covering its urban pars. In 2008 a tent was installed as protection from rain and sun. Being of interest to characterise the microclimate of the remains, six probes with relative humidity and temperature sensors were installed in 2013 for this purpose. Microclimate monitoring allowed us to check relative humidity differences resulting from the groundwater level, as well as inner sensors reaching maximum temperatures higher than the outdoors ones as a consequence of the non-ventilated tent covering the archaeological site. Microclimatic conditions in the archaeological site were deemed detrimental for the conservation of the mosaics. Thus, in summer 2013, expanded clay and geotextile were installed over the mosaics as a corrective action. The outcomes of this study have proven the effectiveness of this solution to control temperature and relative humidity, helping to configure a more stable microclimate suitable for preservation of the mosaic.
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Phase change thermal energy storage methods for combat vehicles, phase 1
NASA Astrophysics Data System (ADS)
Lynch, F. E.
1986-06-01
Three alternative cooling methods, based on latent heat absorption during phase changes, were studied for potential use in combat vehicle microclimate temperature control. Metal hydrides absorb heat as they release hydrogen gas. Plastic crystals change from one solid phase to another, absorbing heat in the process. Liquid air boils at cryogenic temperature and absorbs additional sensible heat as the cold gas mixes with the microclimate air flow. System designs were prepared for each of the three microclimate cooling concepts. These designs provide details about the three phase change materials, their containers and the auxiliary equipment needed to implement each option onboard a combat vehicle. The three concepts were compared on the basis of system mass, system volume and the energy required to regenerate them after use. Metal hydrides were found to be the lightest and smallest option by a large margin. The energy needed to regenerate a hydride thermal storage system can be extracted from the vehicle's exhaust gases.
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Hetem, Robyn S; Maloney, Shane K; Fuller, Andrea; Meyer, Leith C R; Mitchell, Duncan
2007-06-01
Behavioural thermoregulation is an animal's primary defence against changes in the thermal environment. We aimed to validate a remote technique to quantify the thermal environment behaviourally selected by free-ranging ungulates. First, we demonstrated that the temperature of miniature, 30 mm diameter, black globes (miniglobes) could be converted to standard, 150 mm diameter, black globe temperatures. Miniglobe temperature sensors subsequently were fitted to collars on three free-ranging ungulates, namely blue wildebeest (Connochaetes taurinus), impala (Aepyceros melampus) and horse (Equus caballus). Behavioural observations were reflected in animal miniglobe temperatures which differed from those recorded by an identical miniglobe on a nearby exposed weather station. The wildebeest often selected sites protected from the wind, whereas the impala and the horse sheltered from the sun. Nested analysis of variances revealed that the impala and horse selected significantly less variable environments than those recorded at the weather station (P<0.001) over a 20-min time interval, whereas, the microclimates selected by wildebeest tended to be more variable (P=0.08). Correlation of animal miniglobe against weather station miniglobe temperature resulted in regression slopes significantly less than one (P<0.001) for all species studied, implying that, overall, the animals selected cooler microclimates at high environmental heat loads and/or warmer microclimates at low environmental heat loads. We, therefore, have developed an ambulatory device, which can be attached to free-ranging animals, to remotely quantify thermoregulatory behaviour and selected microclimates. (c) 2007 Wiley-Liss, Inc.
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Lightweight Passive Microclimate Cooling Device
1993-03-01
rabrication. No consideration was given to weight. We have examined alternate methods of construction of the backpack and cylinder assembly and thin...13 Figure 7. Water Adsorption on Magnesium Chloride ........... 14 Figure 8. Cylinder Assembly ................................ 20...Figure 9. Backpack Assembly ............................... 21 Figure 10. Unwrapped Vest ................................... 22 Figure 11. Adsorption
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Simple Techniques for Microclimate Measurement.
ERIC Educational Resources Information Center
Unwin, D. M.
1978-01-01
Describes simple ways of measuring the very local climate near the ground, and explains what these measurements mean. Equipment included a solar radiometer, a dew point instrument, and a thermocouple psychrometer. Examples are given of field measurements taken with some of the equipment and the results and their interpretation are discussed.…
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Sedov, A V; Lukicheva, T A; Surovtsev, N A; Akin'shin, A V; Nazarov, L Iu; Miroshnik, S V
1993-01-01
A group of volunteers was exposed to coaction of carbon dioxide (concentration 300 mg/cu m) and heating microclimate (ambient temperature +50 +/- 2 degrees C, relative humidity 20 +/- 5%), simultaneously they received one of the medicines: placebo, bemitil (0.5 g), bromantane (0.25 g) or bemitil (0.5 g) combined with bromantane (0.25 g). Bromantane (0.25 g) or bemitil (0.5 g) combined with bromantane (0.25 g) were proved to be the most effective method to increase stability of the human body against co-action of carbon dioxide and heating microclimate.
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Rajkovich, Nicholas B; Larsen, Larissa
2016-01-25
Collecting a fine scale of microclimate data can help to determine how physical characteristics (e.g., solar radiation, albedo, sky view factor, vegetation) contribute to human exposure to ground and air temperatures. These data also suggest how urban design strategies can reduce the negative impacts of the urban heat island effect. However, urban microclimate measurement poses substantial challenges. For example, data taken at local airports are not representative of the conditions at the neighborhood or district level because of variation in impervious surfaces, vegetation, and waste heat from vehicles and buildings. In addition, fixed weather stations cannot be deployed quickly to capture data from a heat wave. While remote sensing can provide data on land cover and ground surface temperatures, resolution and cost remain significant limitations. This paper describes the design and validation of a mobile measurement bicycle. This bicycle permits movement from space to space within a city to assess the physical and thermal properties of microclimates. The construction of the vehicle builds on investigations of the indoor thermal environment of buildings using thermal comfort carts.
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Rajkovich, Nicholas B.; Larsen, Larissa
2016-01-01
Collecting a fine scale of microclimate data can help to determine how physical characteristics (e.g., solar radiation, albedo, sky view factor, vegetation) contribute to human exposure to ground and air temperatures. These data also suggest how urban design strategies can reduce the negative impacts of the urban heat island effect. However, urban microclimate measurement poses substantial challenges. For example, data taken at local airports are not representative of the conditions at the neighborhood or district level because of variation in impervious surfaces, vegetation, and waste heat from vehicles and buildings. In addition, fixed weather stations cannot be deployed quickly to capture data from a heat wave. While remote sensing can provide data on land cover and ground surface temperatures, resolution and cost remain significant limitations. This paper describes the design and validation of a mobile measurement bicycle. This bicycle permits movement from space to space within a city to assess the physical and thermal properties of microclimates. The construction of the vehicle builds on investigations of the indoor thermal environment of buildings using thermal comfort carts. PMID:26821037
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NASA Astrophysics Data System (ADS)
Cardinale, Tiziana; Rospi, Gianluca; Cardinale, Nicola; Paterino, Lucia; Persia, Ivan
2014-05-01
The Matera Cathedral was built in Apulian-Romanesque style in the thirteenth century on the highest spur of the "Civita" that divides "Sassi" district in two parts. The constructive material is the calcareous stone of the Vaglia, extracted from quarries in the area of Matera. The interior is Baroque and presents several artworks, including: mortars covered with a golden patina, a wooden ceiling, painted canvas and painting frescoes, three minor altars and a major altar of precious white marble, a nativity scene made of local painted limestone. The research had to evaluate the indoor microclimate during and after the restoration works, that also concern the installation of floor heating system to heat the indoor environments. Specifically, we have analyzed the thermal comfort and the effect that the artwork and construction materials inside the Cathedral of Matera have undergone. This evaluation was carried out in two different phases: in the first one we have investigated the state of the art (history of the site, constructive typology and artworks); in the second one we have done a systematic diagnosis and an instrumental one. The analysis were carried out in a qualitative and quantitative way and have allowed us to test indoor microclimatic parameters (air temperature, relative humidity and indoor air velocity), surface temperatures of the envelope and also Fanger's comfort indices (PMV and PPD) according to the UNI EN ISO 7730. The thermal mapping of the wall surface and of the artworks, carried out through thermal imaging camera, and the instrumental measurement campaigns were made both before restoration and after installation of the heating system; in addition measurements were taken with system on and off. The analysis thus made possible to verify that the thermo-hygrometric parameters found, as a result of the recovery operations, meet the limits indicated by the regulations and international studies. In this way, we can affirm that the indoor environment
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Separating temperature from other factors in phenological measurements
NASA Astrophysics Data System (ADS)
Schwartz, Mark D.; Hanes, Jonathan M.; Liang, Liang
2014-09-01
Phenological observations offer a simple and effective way to measure climate change effects on the biosphere. While some species in northern mixed forests show a highly sensitive site preference to microenvironmental differences (i.e., the species is present in certain areas and absent in others), others with a more plastic environmental response (e.g., Acer saccharum, sugar maple) allow provisional separation of the universal "background" phenological variation caused by in situ (possibly biological/genetic) variation from the microclimatic gradients in air temperature. Moran's I tests for spatial autocorrelation among the phenological data showed significant ( α ≤ 0.05) clustering across the study area, but random patterns within the microclimates themselves, with isolated exceptions. In other words, the presence of microclimates throughout the study area generally results in spatial autocorrelation because they impact the overall phenological development of sugar maple trees. However, within each microclimate (where temperature conditions are relatively uniform) there is little or no spatial autocorrelation because phenological differences are due largely to randomly distributed in situ factors. The phenological responses from 2008 and 2009 for two sugar maple phenological stages showed the relationship between air temperature degree-hour departure and phenological change ranged from 0.5 to 1.2 days earlier for each additional 100 degree-hours. Further, the standard deviations of phenological event dates within individual microclimates (for specific events and years) ranged from 2.6 to 3.8 days. Thus, that range of days is inferred to be the "background" phenological variation caused by factors other than air temperature variations, such as genetic differences between individuals.
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Groff, Luke A.; Calhoun, Aram J.K.; Loftin, Cynthia S.
2016-01-01
Poikilothermic species, such as amphibians, endure harsh winter conditions via freeze-tolerance or freeze-avoidance strategies. Freeze-tolerance requires a suite of complex, physiological mechanisms (e.g., cryoprotectant synthesis); however, behavioral strategies (e.g., hibernal habitat selection) may be used to regulate hibernaculum temperatures and promote overwintering survival. We investigated the hibernal ecology of the freeze-tolerant Wood Frog (Lithobates sylvaticus) in north-central Maine. Our objectives were to characterize the species hibernaculum microclimate (temperature, relative humidity), evaluate hibernal habitat selection, and describe the spatial arrangement of breeding, post-breeding, and hibernal habitats. We monitored 15 frogs during two winters (2011/12: N = 10; 2012/13: N = 5), measured hibernal habitat features at micro (2 m) and macro (10 m) spatial scales, and recorded microclimate hourly in three strata (hibernaculum, leaf litter, ambient air). We compared these data to that of 57 random locations with logistic regression models, Akaike Information Criterion, and Kolmogorov–Smirnov tests. Hibernaculum microclimate was significantly different and less variable than leaf litter, ambient air, and random location microclimate. Model averaging indicated that canopy cover (−), leaf litter depth (+), and number of logs and stumps (+; microhabitat only) were important predictors of Wood Frog hibernal habitat. These habitat features likely act to insulate hibernating frogs from extreme and variable air temperatures. For example, decreased canopy cover facilitates increased snowpack depth and earlier snowpack accumulation and melt. Altered winter temperature and precipitation patterns attributable to climate change may reduce snowpack insulation, facilitate greater temperature variation in the underlying hibernacula, and potentially compromise Wood Frog winter survival.
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Seasonal Trends in Airborne Fungal Spores in Coastal California Ecosystems
NASA Astrophysics Data System (ADS)
Morfin, J.; Crandall, S. G.; Gilbert, G. S.
2014-12-01
Airborne fungal spores cause disease in plants and animals and may trigger respiratory illnesses in humans. In terrestrial systems, fungal sporulation, germination, and persistence are strongly regulated by local meteorological conditions. However, few studies investigate how microclimate affects the spatio-temporal dynamics of airborne spores. We measured fungal aerospora abundance and microclimate at varying spatial and time scales in coastal California in three habitat-types: coast redwood forest, mixed-evergreen forest, and maritime chaparral. We asked: 1) is there a difference in total airborne spore concentration between habitats, 2) when do we see peak spore counts, and 3) do spore densities correlate with microclimate conditions? Fungal spores were caught from the air with a volumetric vacuum air spore trap during the wet season (January - March) in 2013 and 2014, as well as monthly in 2014. Initial results suggest that mixed-evergreen forests exhibit the highest amounts of spore abundance in both years compared to the other habitats. This may be due to either a higher diversity of host plants in mixed-evergreen forests or a rich leaf litter layer that may harbor a greater abundance of saprotrophic fungi. Based on pilot data, we predict that temperature and to a lesser degree, relative humidity, will be important microclimate predictors for high spore densities. These data are important for understanding when and under what weather conditions we can expect to see high levels of fungal spores in the air; this can be useful information for managers who are interested in treating diseased plants with fungicides.
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Bogerd, Cornelis Peter; Rechsteiner, Ivo; Wüst, Benno; Rossi, René M; Brühwiler, Paul A
2011-06-01
The goal of the present study was to investigate physiological effects, mainly at the level of the foot, of two sock fabrics with distinct moisture properties. Twelve participants wore two different socks, one on each foot. The following two sock types were used: PP: 99.6% polypropylene and 0.4% elastane and BLEND: 50% Merino wool, 33% polypropylene, and 17% polyamide. The participants walked three times on a treadmill at 5 km h(-1), with no gradient for the first and third phase and a 10% upward inclination for the second walking phase. The microclimate temperature between the boot and foot was measured during walking. Preceding and following the walking phases, additional measurements were carried out at the level of the foot, i.e. skin temperature and skin hydration on three locations and skin friction between the posterior surface of the calcaneus and a glass plate. In addition, the moisture absorption of boots and socks was determined. Differences between the sock fabrics were found for weight gain and microclimate temperature: (i) PP tended to hold less water compared to BLEND, (ii) the boot's microclimate temperature resulted in larger values for BLEND measured at the dorsal surface at the level of the third metatarsal, and (iii) warmer microclimates of the boot were measured for PP compared to BLEND at the distal anterior end of the tibia. The established differences in moisture behavior of both socks did not result in detectable differences in parameters measured on the skin of the foot.
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Wilkinson, Sally; Davies, William J
2008-01-01
The apoplastic pH of intact Forsythiaxintermedia (cv. Lynwood) and tomato (Solanum lycopersicum) plants has been manipulated using buffered foliar sprays, and thereby stomatal conductance (g(s)), leaf growth rate, and plant water loss have been controlled. The more alkaline the pH of the foliar spray, the lower the g(s) and/or leaf growth rate subsequently measured. The most alkaline pH that was applied corresponds to that measured in sap extracted from shoots of tomato and Forsythia plants experiencing, respectively, soil drying or a relatively high photon flux density (PFD), vapour pressure deficit (VPD), and temperature in the leaf microclimate. The negative correlation between PFD/VPD/temperature and g(s) determined in well-watered Forsythia plants exposed to a naturally varying summer microclimate was eliminated by spraying the plants with relatively alkaline but not acidic buffers, providing evidence for a novel pH-based signalling mechanism linking the aerial microclimate with stomatal aperture. Increasing the pH of the foliar spray only reduced g(s) in plants of the abscisic acid (ABA)-deficient flacca mutant of tomato when ABA was simultaneously sprayed onto leaves or injected into stems. In well-watered Forsythia plants exposed to a naturally varying summer microclimate (variable PFD, VPD, and temperature), xylem pH and leaf ABA concentration fluctuated but were positively correlated. Manipulation of foliar apoplastic pH also affected the response of g(s) and leaf growth to ABA injected into stems of intact Forsythia plants. The techniques used here to control physiology and water use in intact growing plants could easily be applied in a horticultural context.
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Boal, Clint W.; Grisham, Blake A.; Haukos, David A.; Zavaleta, Jennifer C.; Dixon, Charles
2014-01-01
Climate models predict that the region of the Great Plains Landscape Conservation Cooperative (GPLCC) will experience increased maximum and minimum temperatures, reduced frequency but greater intensity of precipitation events, and earlier springs. These climate changes along with different landscape management techniques may influence the persistence of the lesser prairie-chicken (Tympanuchus pallidicinctus), a candidate for protection under the Endangered Species Act and a priority species under the GPLCC, in positive or negative ways. The objectives of this study were to conduct (1) a literature review of lesser prairie-chicken nesting phenology and ecology, (2) an analysis of thermal aspects of lesser prairie-chicken nest microclimate data, and (3) an analysis of nest site selection, nest survival, and vegetation response to 10 years of tebuthiuron and/or grazing treatments. We found few reports in the literature containing useful data on the nesting phenology of lesser prairie-chickens; therefore, managers must rely on short-term observations and measurements of parameters that provide some predictive insight into climate impacts on nesting ecology. Our field studies showed that prairie-chickens on nests were able to maintain relatively consistent average nest temperature of 31 °C and nest humidities of 56.8 percent whereas average external temperatures (20.3–35.0 °C) and humidities (35.2–74.9 percent) varied widely throughout the 24 hour (hr) cycle. Grazing and herbicide treatments within our experimental areas were designed to be less intensive than in common practice. We determined nest locations by radio-tagging hen lesser prairie-chickens captured at leks, which are display grounds at which male lesser prairie-chickens aggregate and attempt to attract a female for mating. Because nest locations selected by hen lesser prairie-chicken are strongly associated with the lek at which they were captured, we assessed nesting habitat use on the basis of hens
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Mantilla-Contreras, Jasmin
2018-01-01
Environmental and leaf trait effects on herbivory are supposed to vary among different feeding guilds. Herbivores also show variability in their preferences for plant ontogenetic stages. Along the vertical forest gradient, environmental conditions change, and trees represent juvenile and adult individuals in the understorey and canopy, respectively. This study was conducted in ten forests sites in Central Germany for the enrichment of canopy research in temperate forests. Arthropod herbivory of different feeding traces was surveyed on leaves of Fagus sylvatica Linnaeus (European beech; Fagaceae) in three strata. Effects of microclimate, leaf traits, and plant ontogenetic stage were analyzed as determining parameters for herbivory. The highest herbivory was caused by exophagous feeding traces. Herbivore attack levels varied along the vertical forest gradient for most feeding traces with distinct patterns. If differences of herbivory levels were present, they only occurred between juvenile and adult F. sylvatica individuals, but not between the lower and upper canopy. In contrast, differences of microclimate and important leaf traits were present between the lower and upper canopy. In conclusion, the plant ontogenetic stage had a stronger effect on herbivory than microclimate or leaf traits along the vertical forest gradient. PMID:29373542
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Analyzing the edge effects in a Brazilian seasonally dry tropical forest.
Arruda, D M; Eisenlohr, P V
2016-02-01
Due to the deciduous nature of dry forests (widely known as seasonally dry tropical forests) they are subject to microclimatic conditions not experienced in other forest formations. Close examinations of the theory of edge effects in dry forests are still rare and a number of questions arise in terms of this topic. In light of this situation we examined a fragment of the dry forest to respond to the following questions: (I) Are there differences in canopy cover along the edge-interior gradient during the dry season? (II) How does the microclimate (air temperature, soil temperature, and relative humidity) vary along that gradient? (III) How does the microclimate influence tree species richness, evenness and abundance along that gradient? (IV) Are certain tree species more dominant closer to the forest edges? Regressions were performed to address these questions. Their coefficients did not significantly vary from zero. Apparently, the uniform openness of the forest canopy caused a homogeneous internal microclimate, without significant differentiation in habitats that would allow modifications in biotic variables tested. We conclude that the processes of edge effect commonly seen in humid forests, not was shared with the dry forest assessed.
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NASA Astrophysics Data System (ADS)
Stelling, Jonathan M.; Yu, Zicheng; Loisel, Julie; Beilman, David W.
2018-05-01
The western Antarctic Peninsula experienced rapid warming in the second half of the 20th century, which has increased vascular plant abundance and moss productivity. To better understand long-term ecological responses, we used paleoecological and microclimate data to investigate dynamics of late-Holocene peatbank development and landscape influences. In peatbank cores from three locations on Litchfield Island (64°46‧S; 64°06‧W) high-resolution plant macrofossil and geochemical analysis show contrasting ecological and environmental changes. Two peatbanks on the southwest- and west-facing slopes of two separate hills are about 500 years old in contrast to a north-facing peatbank that is 2700 years old. The period from 1350 to 450 calibrated years before present (cal yr BP) at the north-facing peatbank had low accumulation (0.25 mm yr-1, 36 g OM m-2 yr-1), which we interpret as a period of low temperature and increased snow cover. Microclimate differences were amplified by this regional climate cooling, causing the delayed peat initiation on non-equator-facing slopes. Over the last 500 years, the north-facing peatbank had an accumulation rate (0.7 mm yr-1, 76 g OM m-2 yr-1) that was lower than the southwest- and west-facing peatbanks (1-1.4 mm yr-1, 97-110 g OM m-2 yr-1). Microclimate data suggest that slope aspect on Litchfield Island influences soil temperature, snow cover, and water availability that in turn affect growing-season lengths and peat accumulation. Plant macrofossils preserved in the north- and west-facing peatbanks show a centennial-scale pattern of fluctuation in relative abundance of dry-adapted Polytrichum strictum and wetter Chorisodontium aciphyllum mosses. Our results suggest that moss communities responded to external environmental influence, particularly those affecting moisture conditions, while topography and resultant microclimate differences had a strong influence on peat accumulation.
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Kleckova, Irena; Klecka, Jan
2016-01-01
Understanding the potential of animals to immediately respond to changing temperatures is imperative for predicting the effects of climate change on biodiversity. Ectothermic animals, such as insects, use behavioural thermoregulation to keep their body temperature within suitable limits. It may be particularly important at warm margins of species occurrence, where populations are sensitive to increasing air temperatures. In the field, we studied thermal requirements and behavioural thermoregulation in low-altitude populations of the Satyrinae butterflies Erebia aethiops, E. euryale and E. medusa. We compared the relationship of individual body temperature with air and microhabitat temperatures for the low-altitude Erebia species to our data on seven mountain species, including a high-altitude population of E. euryale, studied in the Alps. We found that the grassland butterfly E. medusa was well adapted to the warm lowland climate and it was active under the highest air temperatures and kept the highest body temperature of all species. Contrarily, the woodland species, E. aethiops and a low-altitude population of E. euryale, kept lower body temperatures and did not search for warm microclimates as much as other species. Furthermore, temperature-dependence of daily activities also differed between the three low-altitude and the mountain species. Lastly, the different responses to ambient temperature between the low- and high-altitude populations of E. euryale suggest possible local adaptations to different climates. We highlight the importance of habitat heterogeneity for long-term species survival, because it is expected to buffer climate change consequences by providing a variety of microclimates, which can be actively explored by adults. Alpine species can take advantage of warm microclimates, while low-altitude grassland species may retreat to colder microhabitats to escape heat, if needed. However, we conclude that lowland populations of woodland species may be
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NASA Astrophysics Data System (ADS)
Percy, M.; Singha, K.; Benninger, L. K.; Riveros-Iregui, D. A.; Mirus, B. B.
2015-12-01
The spatial and temporal distribution of soil moisture in tropical critical zones depends upon a number of variables including topographic position, soil texture, overlying vegetation, and local microclimates. We investigate the influences on soil moisture on a tropical basaltic island (San Cristóbal, Galápagos) across a variety of microclimates during the transition from the wetter to the drier season. We used multiple approaches to characterize spatial and temporal patterns in soil moisture at four sites across microclimates ranging from arid to very humid. The microclimates on San Cristóbal vary with elevation, so our monitoring includes two sites in the transitional zone at lower elevations, one in the humid zone at moderate elevations, and one in the very humid zone in higher elevations. We made over 250 near-surface point measurements per site using a Hydrosense II probe, and estimated the lateral variability in soil moisture across each site with an EM-31 electrical conductivity meter. We also monitored continuous time-series of in-situ soil moisture dynamics using three nested TDR probes collocated with meteorological stations at each of the sites. Preliminary analysis indicates that soils in the very humid zone have lower electrical conductivities across all the hillslopes as compared to the humid and transitional zones, which suggests that additional factors beyond climate and slope position are important. While soil texture across the very humid site is fairly uniform, variations in vegetation have a strong control on soil moisture patterns. At the remaining sites the vegetation patterns also have a very strong local influence on soil moisture, but correlation between the depth to clay layers and soil moisture patterns suggests that mineralogy is also important. Our findings suggest that the microclimatic setting is a crucial consideration for understanding relations between vegetation, soil texture, and soil-moisture dynamics in tropical critical
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NASA Astrophysics Data System (ADS)
Kearney, Michael R.; Maino, James L.
2018-06-01
Accurate models of soil moisture are vital for solving core problems in meteorology, hydrology, agriculture and ecology. The capacity for soil moisture modelling is growing rapidly with the development of high-resolution, continent-scale gridded weather and soil data together with advances in modelling methods. In particular, the GlobalSoilMap.net initiative represents next-generation, depth-specific gridded soil products that may substantially increase soil moisture modelling capacity. Here we present an implementation of Campbell's infiltration and redistribution model within the NicheMapR microclimate modelling package for the R environment, and use it to assess the predictive power provided by the GlobalSoilMap.net product Soil and Landscape Grid of Australia (SLGA, ∼100 m) as well as the coarser resolution global product SoilGrids (SG, ∼250 m). Predictions were tested in detail against 3 years of root-zone (3-75 cm) soil moisture observation data from 35 monitoring sites within the OzNet project in Australia, with additional tests of the finalised modelling approach against cosmic-ray neutron (CosmOz, 0-50 cm, 9 sites from 2011 to 2017) and satellite (ASCAT, 0-2 cm, continent-wide from 2007 to 2009) observations. The model was forced by daily 0.05° (∼5 km) gridded meteorological data. The NicheMapR system predicted soil moisture to within experimental error for all data sets. Using the SLGA or the SG soil database, the OzNet soil moisture could be predicted with a root mean square error (rmse) of ∼0.075 m3 m-3 and a correlation coefficient (r) of 0.65 consistently through the soil profile without any parameter tuning. Soil moisture predictions based on the SLGA and SG datasets were ≈ 17% closer to the observations than when using a chloropleth-derived soil data set (Digital Atlas of Australian Soils), with the greatest improvements occurring for deeper layers. The CosmOz observations were predicted with similar accuracy (r = 0.76 and rmse of ∼0
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NASA Astrophysics Data System (ADS)
Uniyal, S.; Singh, S.; Rao, S. S.
2017-12-01
Trees Outside Forest (TOF) grow on a variety of landscapes , e.g. linear, scattered, block etc. and include unique range of species that are specific to the local environmental and socio-cultural conditions. TOF usefulness came into knowledge when the ongoing anthropogenic activities increases the CO2 concentration in the atmosphere and it has been understood that CO2 can also be sequestered by increasing rate of afforestation.This study illustrates a methodology to estimate individual tree phytomass, their contribution to the environment and microclimate, spatial distribution of TOF phytomass and their carbon storage in Gwalior and Sheopur districts of Madhya Pradesh using very high resolution satellite data. Attempt has been made to estimate phytomass at pixel level also using various regression models. Phytomass is an important parameter to assess the atmospheric carbon that is harvested by trees .More the amount of phytomass more will be the Carbon content of trees and in similar way more will be their contribution for regulation of CO2 and vice versa. Tree Canopies extraction was done using very high resolution satellite data within an area of 5´5 km grids using various remote sensing techniques. Field data were collected from different types of TOFs, e.g. linear, scattered, block etc. from varying plot shapes and sizes, and Stratum-wise phytomass was estimated. Findings of study reported here says that varying phytomass range has been observed for road, agriculture and settlement with varying number of individual trees.The Phytomass in scattered TOFs varied from 0.22 to 15.68 t/ha and carbon content 0.104 to 7.4tC whereas, in linear TOFs it varied from 5.26 to 156.71 t/ha with carbon content 2.49 to 74.43tC. Phytomass along the road-side varied from 20.75 to 879.8 t/ha and carbon content 9.85 to 417.90 tC. Stratum-wise total phytomass and carbon content in areas having TOF was estimated. Of the 10 grids considered, the maximum Phytomass of 1363 tonnes with
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Perceptions of temperature, moisture and comfort in clothing during environmental transients.
Li, Y
2005-02-22
A study has been carried out to investigate the psychophysical mechanisms of the perception of temperature and moisture sensations in clothing during environmental transients. A series of wear trials was conducted to measure the psychological perception of thermal and moisture sensations and the simultaneous temperature and humidity at the skin surface, fabric surface and in the clothing under simulated moderate rain conditions. Jumpers made from wool and acrylic fibres were used in the trial. Analysis has been carried out to study the relationship between psychological perceptions of temperature and moisture and the objectively measured skin and fabric temperatures and relative humidity in clothing microclimate. The perception of warmth seems to follow Fechner's law and Stevens' power law, having positive relationships with the skin temperature and fabric temperatures. The perception of dampness appears to follow Fechner's law more closely than Stevens' power law with a negative relationship with skin temperature, and is nonlinearly and positively correlated with relative humidity in clothing microclimate. The perception of comfort is positively related to the perception of warmth and negatively to the perception of dampness. This perception of comfort is positively related to the skin temperature, which appears to follow both Fechner's law and Stevens' law, also non-linearly and negatively related to relative humidity in clothing microclimate.
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Lozano, Yudi M; Armas, Cristina; Hortal, Sara; Casanoves, Fernando; Pugnaire, Francisco I
2017-12-01
Nurse plants promote establishment of other plant species by buffering climate extremes and improving soil properties. Soil biota plays an important role, but an analysis to disentangle the effects of soil microorganisms, soil properties and microclimate on facilitation is lacking. In three microhabitats (gaps, small and large Retama shrubs), we placed six microcosms with sterilized soil, two per soil origin (i.e. from each microhabitat). One in every pair received an alive, and the other a sterile, inoculum from its own soil. Seeds of annual plants were sown into the microcosms. Germination, survival and biomass were monitored. Soil bacterial communities were characterized by pyrosequencing. Germination in living Retama inoculum was nearly double that of germination in sterile inoculum. Germination was greater under Retama canopies than in gaps. Biomass was up to three times higher in nurse than in gap soils. Soil microorganisms, soil properties and microclimate showed a range of positive to negative effects on understory plants depending on species identity and life stage. Nurse soil microorganisms promoted germination, but the effect was smaller than the positive effects of soil properties and microclimate under nurses. Nurse below-ground environment (soil properties and microorganisms) promoted plant growth and survival more than nurse microhabitat. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.
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ERIC Educational Resources Information Center
Fisher, Carol J.
1978-01-01
Presents ideas and activities for teaching basic skills including vocabulary building, learning science from the microclimates, using tape recorders to teach reading, and using monsters to teach metrics. (JMB)
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Wireless Sensor Platform for Cultural Heritage Monitoring and Modeling System.
Klein, Levente J; Bermudez, Sergio A; Schrott, Alejandro G; Tsukada, Masahiko; Dionisi-Vici, Paolo; Kargere, Lucretia; Marianno, Fernando; Hamann, Hendrik F; López, Vanessa; Leona, Marco
2017-08-31
Results from three years of continuous monitoring of environmental conditions using a wireless sensor platform installed at The Cloisters, the medieval branch of the New York Metropolitan Museum of Art, are presented. The platform comprises more than 200 sensors that were distributed in five galleries to assess temperature and air flow and to quantify microclimate changes using physics-based and statistical models. The wireless sensor network data shows a very stable environment within the galleries, while the dense monitoring enables localized monitoring of subtle changes in air quality trends and impact of visitors on the microclimate conditions. The high spatial and temporal resolution data serves as a baseline study to understand the impact of visitors and building operations on the long-term preservation of art objects.
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A dew point signaller for conservation of works of art.
Camuffo, D; Valcher, S
1986-03-01
All works of art, from paintings, frescoes, sculptures, to monuments and buildings, are affected by diurnal and seasonal variations of the local microclimate, which induce interactions with the environmental atmosphere. Heat and vapour exchanges cause fluxes of heat and mass between the surface and the atmosphere, and may favour the agressivity of environmental pollutants. Condensation-evaporation cycles are recognized as being very important processes which adversely affect the life-time of the work of art. The need to control the microclimate or to stop condensation processes has been resolved by means of a dew-point signaller especially designed to overcome this problem. This paper discusses the characteristics of this device as well as the environmental philosophy which should be followed when conserving works of art.
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Functions of perch relocations in a communal night roost of wintering bald eagles
Yackel Adams, A.A.; Skagen, S.K.; Knight, R.L.
2000-01-01
We investigated the functions of perch relocations within a communal night roost of wintering bald eagles (Haliaeetus leucocephalus) along the Nooksack River, Washington, during two winters. We tested seven predictions of two nonexclusive hypotheses: (1) bald eagles relocate within roosts to assess foraging success of conspecifics and (2) bald eagles relocate to obtain thermoregulatory benefits from an improved microclimate. Additionally, we gathered descriptive information to allow refinement of further alternative hypotheses. We rejected the hypothesis that relocations are a means of assessing foraging success. Contrary to our expectations, immature eagles did not relocate to be closer to adults, and relocations were less frequent when food was less abundant. Our data support the hypothesis that eagles relocate within night roosts to obtain a favorable microclimate during winters when they are subjected to cold stress and food stress. In both winters, relocations were more frequent in the evening than in the morning. In both winters, most evening relocations were to the center of the roost rather than to its edge, and the frequency of relocation to the center was greater when temperatures were low. The microclimate hypothesis, however, explains only a limited number of relocations. Based on our findings, it is likely that relocation has multiple functions, including establishing and (or) maintaining foraging associations, establishing and (or) maintaining social-dominance hierarchies when food is less abundant, and nonsocial activities.
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Aridity and decomposition processes in complex landscapes
NASA Astrophysics Data System (ADS)
Ossola, Alessandro; Nyman, Petter
2015-04-01
Decomposition of organic matter is a key biogeochemical process contributing to nutrient cycles, carbon fluxes and soil development. The activity of decomposers depends on microclimate, with temperature and rainfall being major drivers. In complex terrain the fine-scale variation in microclimate (and hence water availability) as a result of slope orientation is caused by differences in incoming radiation and surface temperature. Aridity, measured as the long-term balance between net radiation and rainfall, is a metric that can be used to represent variations in water availability within the landscape. Since aridity metrics can be obtained at fine spatial scales, they could theoretically be used to investigate how decomposition processes vary across complex landscapes. In this study, four research sites were selected in tall open sclerophyll forest along a aridity gradient (Budyko dryness index ranging from 1.56 -2.22) where microclimate, litter moisture and soil moisture were monitored continuously for one year. Litter bags were packed to estimate decomposition rates (k) using leaves of a tree species not present in the study area (Eucalyptus globulus) in order to avoid home-field advantage effects. Litter mass loss was measured to assess the activity of macro-decomposers (6mm litter bag mesh size), meso-decomposers (1 mm mesh), microbes above-ground (0.2 mm mesh) and microbes below-ground (2 cm depth, 0.2 mm mesh). Four replicates for each set of bags were installed at each site and bags were collected at 1, 2, 4, 7 and 12 months since installation. We first tested whether differences in microclimate due to slope orientation have significant effects on decomposition processes. Then the dryness index was related to decomposition rates to evaluate if small-scale variation in decomposition can be predicted using readily available information on rainfall and radiation. Decomposition rates (k), calculated fitting single pool negative exponential models, generally
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Wireless Sensor Platform for Cultural Heritage Monitoring and Modeling System
Bermudez, Sergio A.; Schrott, Alejandro G.; Tsukada, Masahiko; Kargere, Lucretia; Marianno, Fernando; Hamann, Hendrik F.; López, Vanessa; Leona, Marco
2017-01-01
Results from three years of continuous monitoring of environmental conditions using a wireless sensor platform installed at The Cloisters, the medieval branch of the New York Metropolitan Museum of Art, are presented. The platform comprises more than 200 sensors that were distributed in five galleries to assess temperature and air flow and to quantify microclimate changes using physics-based and statistical models. The wireless sensor network data shows a very stable environment within the galleries, while the dense monitoring enables localized monitoring of subtle changes in air quality trends and impact of visitors on the microclimate conditions. The high spatial and temporal resolution data serves as a baseline study to understand the impact of visitors and building operations on the long-term preservation of art objects. PMID:28858223
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Microclimate moderates plant responses to macroclimate warming.
De Frenne, Pieter; Rodríguez-Sánchez, Francisco; Coomes, David Anthony; Baeten, Lander; Verstraeten, Gorik; Vellend, Mark; Bernhardt-Römermann, Markus; Brown, Carissa D; Brunet, Jörg; Cornelis, Johnny; Decocq, Guillaume M; Dierschke, Hartmut; Eriksson, Ove; Gilliam, Frank S; Hédl, Radim; Heinken, Thilo; Hermy, Martin; Hommel, Patrick; Jenkins, Michael A; Kelly, Daniel L; Kirby, Keith J; Mitchell, Fraser J G; Naaf, Tobias; Newman, Miles; Peterken, George; Petrík, Petr; Schultz, Jan; Sonnier, Grégory; Van Calster, Hans; Waller, Donald M; Walther, Gian-Reto; White, Peter S; Woods, Kerry D; Wulf, Monika; Graae, Bente Jessen; Verheyen, Kris
2013-11-12
Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., "thermophilization" of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that "climatic lags" may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over an interval of 12-67 y, we document significant thermophilization of ground-layer plant communities. These changes reflect concurrent declines in species adapted to cooler conditions and increases in species adapted to warmer conditions. However, thermophilization, particularly the increase of warm-adapted species, is attenuated in forests whose canopies have become denser, probably reflecting cooler growing-season ground temperatures via increased shading. As standing stocks of trees have increased in many temperate forests in recent decades, local microclimatic effects may commonly be moderating the impacts of macroclimate warming on forest understories. Conversely, increases in harvesting woody biomass--e.g., for bioenergy--may open forest canopies and accelerate thermophilization of temperate forest biodiversity.
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Microclimate moderates plant responses to macroclimate warming
De Frenne, Pieter; Rodríguez-Sánchez, Francisco; Coomes, David Anthony; Baeten, Lander; Verstraeten, Gorik; Vellend, Mark; Bernhardt-Römermann, Markus; Brown, Carissa D.; Brunet, Jörg; Cornelis, Johnny; Decocq, Guillaume M.; Dierschke, Hartmut; Eriksson, Ove; Gilliam, Frank S.; Hédl, Radim; Heinken, Thilo; Hermy, Martin; Hommel, Patrick; Jenkins, Michael A.; Kelly, Daniel L.; Kirby, Keith J.; Mitchell, Fraser J. G.; Naaf, Tobias; Newman, Miles; Peterken, George; Petřík, Petr; Schultz, Jan; Sonnier, Grégory; Van Calster, Hans; Waller, Donald M.; Walther, Gian-Reto; White, Peter S.; Woods, Kerry D.; Wulf, Monika; Graae, Bente Jessen; Verheyen, Kris
2013-01-01
Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., “thermophilization” of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that “climatic lags” may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over an interval of 12–67 y, we document significant thermophilization of ground-layer plant communities. These changes reflect concurrent declines in species adapted to cooler conditions and increases in species adapted to warmer conditions. However, thermophilization, particularly the increase of warm-adapted species, is attenuated in forests whose canopies have become denser, probably reflecting cooler growing-season ground temperatures via increased shading. As standing stocks of trees have increased in many temperate forests in recent decades, local microclimatic effects may commonly be moderating the impacts of macroclimate warming on forest understories. Conversely, increases in harvesting woody biomass—e.g., for bioenergy—may open forest canopies and accelerate thermophilization of temperate forest biodiversity. PMID:24167287
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NASA Astrophysics Data System (ADS)
Salvatore, M. R.; Mustard, J. F.; Head, J. W.; Marchant, D. R.; Wyatt, M. B.; Seeley, J.
2012-03-01
Primary igneous and secondary alteration signatures can be resolved using orbital spectroscopy over mafic regions of the McMurdo Dry Valleys. We assess the nature of these signatures and their link to surface stability and regional microclimates.
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Apple production and quality when cultivated under anti-hail cover in Southern Brazil
NASA Astrophysics Data System (ADS)
Bosco, Leosane Cristina; Bergamaschi, Homero; Cardoso, Loana Silveira; de Paula, Viviane Aires; Marodin, Gilmar Arduino Bettio; Nachtigall, Gilmar Ribeiro
2015-07-01
Anti-hail nets may change the microclimate of orchards and hence modify the physicochemical and sensory characteristics of fruits. The present study aimed to evaluate the effects of anti-hail nets on the physical, chemical, and sensory attributes of apples grown in southern Brazil. The study was conducted in commercial orchards, with apples grown under a black anti-hail net under an open sky during the 2008/2009, 2009/2010, and 2010/2011 cycles. Measurements of photosynthetically active radiation were collected at both sites. Physical, chemical, and sensory analyses of fruits were performed in the laboratory. The anti-hail net reduced incident photosynthetically active radiation by 32 %. The light spectrum in the canopy changed the corresponding R/FR (red/far-red) ratio in the lower and upper canopy layers from 0.27 to 1.55, respectively. In contrast to the majority of microclimate studies carried out in the temperate zones of the northern hemisphere, this study in the southern hemisphere showed that although it reduced the incident solar radiation, the cover did not change the color or organoleptic characteristics of "Royal Gala" and "Fuji Suprema" apples. The net cover prolonged the subperiod between fruit setting and harvesting, thus slowing fruit ripening. Therefore, the use of anti-hail nets on apple orchards is a suitable alternative for the protection of apple trees against hail because it causes only small changes in the microclimate and in the maturation period, ensuring fruit production without affecting its quality.
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Apple production and quality when cultivated under anti-hail cover in Southern Brazil.
Bosco, Leosane Cristina; Bergamaschi, Homero; Cardoso, Loana Silveira; de Paula, Viviane Aires; Marodin, Gilmar Arduino Bettio; Nachtigall, Gilmar Ribeiro
2015-07-01
Anti-hail nets may change the microclimate of orchards and hence modify the physicochemical and sensory characteristics of fruits. The present study aimed to evaluate the effects of anti-hail nets on the physical, chemical, and sensory attributes of apples grown in southern Brazil. The study was conducted in commercial orchards, with apples grown under a black anti-hail net under an open sky during the 2008/2009, 2009/2010, and 2010/2011 cycles. Measurements of photosynthetically active radiation were collected at both sites. Physical, chemical, and sensory analyses of fruits were performed in the laboratory. The anti-hail net reduced incident photosynthetically active radiation by 32%. The light spectrum in the canopy changed the corresponding R/FR (red/far-red) ratio in the lower and upper canopy layers from 0.27 to 1.55, respectively. In contrast to the majority of microclimate studies carried out in the temperate zones of the northern hemisphere, this study in the southern hemisphere showed that although it reduced the incident solar radiation, the cover did not change the color or organoleptic characteristics of "Royal Gala" and "Fuji Suprema" apples. The net cover prolonged the subperiod between fruit setting and harvesting, thus slowing fruit ripening. Therefore, the use of anti-hail nets on apple orchards is a suitable alternative for the protection of apple trees against hail because it causes only small changes in the microclimate and in the maturation period, ensuring fruit production without affecting its quality.
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Ginocchio, Rosanna; Carvallo, Gastón; Toro, Ignacia; Bustamante, Elena; Silva, Yasna; Sepúlveda, Nancy
2004-01-01
Soil chemical changes produced by metal smelters have mainly been studied on a large scale. In terms of plant survival, determination of small scale variability may be more important because less toxic microhabitats may represent safe sites for successful recruitment and thus for plant survival. Three dominant microhabitats (open spaces and areas below the canopy of Sphaeralcea obtusiloba and Baccharis linearis shrubs) were defined in a heavily polluted area near a copper smelter and characterised in terms of microclimate, general soil chemistry, total and extractable metal concentrations in the soil profile (A0 horizon, 0-5 and 15-20 cm depth), and seedling densities. Results indicated a strong variability in microclimate and soil chemistry not only in the soil profile but also among microhabitats. Air/soil temperatures, radiation and wind speed were much lower under the canopy of shrubs, particularly during the plant growth season. Soil acidification was detected on top layers (0-5 cm depth) of all microhabitats while higher concentrations of N, Cu and Cd were detected on litter and top soil layers below shrubs when compared to open spaces; however, high organic matter content below shrubs decreased bioavailability of metals. Plant recruitment was concentrated under shrub canopies; this may be explained as a result of the nursery effect exerted by shrubs in terms of providing a more favourable microclimate, along with better soil conditions in terms of macronutrients and metal bioavailability.
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NASA Astrophysics Data System (ADS)
Suuronen, Anna; Muñoz-Escobar, Christian; Lensu, Anssi; Kuitunen, Markku; Guajardo Celis, Natalia; Espinoza Astudillo, Pablo; Ferrú, Marcos; Taucare-Ríos, Andrés; Miranda, Marcelo; Kukkonen, Jussi V. K.
2017-10-01
The renewable energy sector is growing at a rapid pace in northern Chile and the solar energy potential is one of the best worldwide. Therefore, many types of solar power plant facilities are being built to take advantage of this renewable energy resource. Solar energy is considered a clean source of energy, but there are potential environmental effects of solar technology, such as landscape fragmentation, extinction of local biota, microclimate changes, among others. To be able to minimize environmental impacts of solar power plants, it is important to know what kind of environmental conditions solar power plants create. This study provides information about abiotic and biotic conditions in the vicinity of photovoltaic solar power plants. Herein, the influence of these power plants as drivers of new microclimate conditions and arthropods diversity composition in the Atacama Desert was evaluated. Microclimatic conditions between panel mounts was found to be more extreme than in the surrounding desert yet beneath the panels temperature is lower and relative humidity higher than outside the panel area. Arthropod species composition was altered in fixed-mount panel installations. In contrast, solar tracking technology showed less influence on microclimate and species composition between Sun and Shade in the power plant. Shady conditions provided a refuge for arthropod species in both installation types. For example, Dipterans were more abundant in the shade whereas Solifugaes were seldom present in the shade. The presented findings have relevance for the sustainable planning and construction of solar power plants.
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Suuronen, Anna; Muñoz-Escobar, Christian; Lensu, Anssi; Kuitunen, Markku; Guajardo Celis, Natalia; Espinoza Astudillo, Pablo; Ferrú, Marcos; Taucare-Ríos, Andrés; Miranda, Marcelo; Kukkonen, Jussi V K
2017-10-01
The renewable energy sector is growing at a rapid pace in northern Chile and the solar energy potential is one of the best worldwide. Therefore, many types of solar power plant facilities are being built to take advantage of this renewable energy resource. Solar energy is considered a clean source of energy, but there are potential environmental effects of solar technology, such as landscape fragmentation, extinction of local biota, microclimate changes, among others. To be able to minimize environmental impacts of solar power plants, it is important to know what kind of environmental conditions solar power plants create. This study provides information about abiotic and biotic conditions in the vicinity of photovoltaic solar power plants. Herein, the influence of these power plants as drivers of new microclimate conditions and arthropods diversity composition in the Atacama Desert was evaluated. Microclimatic conditions between panel mounts was found to be more extreme than in the surrounding desert yet beneath the panels temperature is lower and relative humidity higher than outside the panel area. Arthropod species composition was altered in fixed-mount panel installations. In contrast, solar tracking technology showed less influence on microclimate and species composition between Sun and Shade in the power plant. Shady conditions provided a refuge for arthropod species in both installation types. For example, Dipterans were more abundant in the shade whereas Solifugaes were seldom present in the shade. The presented findings have relevance for the sustainable planning and construction of solar power plants.
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Darby, Alexander; Draguljić, Danel; Glunk, Andrew; Gotsch, Sybil G
2016-10-01
Microclimate in the tropical montane cloud forest (TMCF) is variable on both spatial and temporal scales and can lead to large fluctuations in both leaf-level transpiration and whole plant water use. While variation in transpiration has been found in TMCFs, the influence of different microclimatic drivers on plant water relations in this ecosystem has been relatively understudied. Within the TMCF, epiphytes may be particularly affected by natural variation in microclimate due to their partial or complete disassociation from soil resources. In this study, we examined the effects of seasonal microclimate on whole plant water balance in epiphytes in both an observational and a manipulative experiment. We also evaluated the effects of different microclimatic drivers using three hierarchical linear (mixed) models. On average, 31 % of total positive sap flow was recovered via foliar water uptake (FWU) over the course of the study. We found that precipitation was the greatest driver of foliar water uptake and nighttime sap flow in our study species and that both VPD and precipitation were important drivers to daytime sap flow. We also found that despite adaptations to withstand seasonal drought, an extended dry period caused severe desiccation in most plants despite a large reduction in leaf-level and whole plant transpiration. Our results indicate that the epiphytes studied rely on FWU to maintain positive water balance in the dry season and that increases in dry periods in the TMCF may be detrimental to these common members of the epiphyte community.
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Most scenario‐based climate modeling studies indicate that replacing temperate forest with cropland will promote cooling by reducing surface air temperatures. These results are inconsistent with fieldbased microclimate studies that have found that forests are cooler, wetter, and...
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Herman, R.; O’Brien, S.
Using our own prototype sensor arrays that were deployed to collect microclimate data, we were able to visualize distinct differences in temperature, wind speed, and humidity over very small ranges of distance. We collected data across four polygons within the Barrow Environmental Observatory site. Our prototype microclimate arrays were based on an Arduino microcontroller, DS18B20 temperature sensors, DHT11 relative humidity/temperature sensors, and Vernier anemometers. Data were obtained in a small grid pattern with four sensors spaced 60 cm apart along the x-axis, and moved at 60 cm increments along a y-line across a polygon. Overlaying bird nest location with suchmore » data has allowed us to better answer our research question, “How do Arctic birds choose where to nest to maximize fitness in harsh Arctic environments?”« less
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Paper birch: Sentinels of climate change in the Niobrara River Valley, Nebraska
Stroh, Esther D.
2011-01-01
The Niobrara River Valley in the northern Great Plains supports scattered stands of paper birch (Betula papyrifera Marsh), a species more typical of boreal forests. These birch stands are considered to be relictual populations that have persisted since the end of the Wisconsin glaciation. Localized summer microclimates have likely facilitated the persistence of birch populations in a region otherwise unsuitable for the species. Dieback of canopy-sized birch has been observed throughout the valley in recent years, although no onset dates are documented. Changes in spring weather patterns may be causing rootlet injury so that trees die in spite of the still-cool summer microclimates. Current weather patterns, combined with little evidence of recruitment of young birch and great geographic distances from potential immigrant sources, make the future persistence of birch in the Niobrara River Valley stands uncertain.
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Thermal Comfort and Sensation in Men Wearing a Cooling System Controlled by Skin Temperature
2007-07-01
The study was done to determine whether thermal comfort (TC), thermal sensation (TS), and subjective factors gauging environmental stress were...improvement in thermal comfort . Methods: Eight male volunteers exercised at moderate work intensity (425 W) in three microclimate cooling tests. The
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Grape anthocyanin altered by absolute sunlight exclusion
USDA-ARS?s Scientific Manuscript database
This research was conducted to clarify anthocyanin accumulation within ‘Merlot’ grapes in response to microclimate, specifically to light incidence, temperature, and humidity. Treatment grape clusters were light-excluded during ripening by opaque white polypropylene enclosures, during which light in...
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THE RESPONSE OF ANIMAL RANGE TO CLIMATIC AND LAND-USE CHANGES
The geographic ranges of animal taxa seem much more complex than those of plants, since mobile animals may be constrained by many factors other than readily measurable climatic conditions. These additional factors may include microclimate and availability of particular plant type...
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USDA-ARS?s Scientific Manuscript database
Background: Halyomorpha halys (Hemiptera: Pentatomidae) is an invasive species from Asia causing major economic losses in agricultural production in the mid-Atlantic region of the United States. H. halys overwinters in sheltered locations with protective and less extreme microclimates. Unlike ot...
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Realizing ecosystem services: wetland hydrologic function along a gradient of ecosystem condition.
McLaughlin, Daniel L; Cohen, Matthew J
2013-10-01
Wetlands provide numerous ecosystem services, from habitat provision to pollutant removal, floodwater storage, and microclimate regulation. Delivery of particular services relies on specific ecological functions, and thus to varying degree on wetland ecological condition, commonly quantified as departure from minimally impacted reference sites. Condition assessments are widely adopted as regulatory indicators of ecosystem function, and for some services (e.g., habitat) links between condition and function are often direct. For others, however, links are more tenuous, and using condition alone to enumerate ecosystem value (e.g., for compensatory mitigation) may underestimate important services. Hydrologic function affects many services cited in support of wetland protection both directly (floodwater retention, microclimate regulation) and indirectly (biogeochemical cycling, pollutant removal). We investigated links between condition and hydrologic function to test the hypothesis, embedded in regulatory assessment of wetland value, that condition predicts function. Condition was assessed using rapid and intensive approaches, including Florida's official wetland assessment tool, in 11 isolated forested wetlands in north Florida (USA) spanning a land use intensity gradient. Hydrologic function was assessed using hydrologic regime (mean, variance, and rates of change of water depth), and measurements of groundwater exchange and evapotranspiration (ET). Despite a wide range in condition, no systematic variation in hydrologic regime was observed; indeed reference sites spanned the full range of variation. In contrast, ET was affected by land use, with higher rates in intensive (agriculture and urban) landscapes in response to higher leaf area. ET determines latent heat exchange, which regulates microclimate, a valuable service in urban heat islands. Higher ET also indicates higher productivity and thus carbon cycling. Groundwater exchange regularly reversed flow direction
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Forest litter insect community succession in clearcuts of Norway spruce
Arturas Gedminas
2003-01-01
Insects are subjected to stress in fresh clearcuts due to changes in microclimate, vegetation, and trophic links. The objective of this study was to investigate succession in litter insect communities (most abundant by number of species and individuals of all clearcut insects).
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Richard C. Cobb; David M. Rizzo
2016-01-01
Forest pathogens have strong potential to shape ecosystem function by altering litterfall, microclimate, and changing community structure. We quantified changes in litter decomposition from a set of distinct diseases caused by Phytophthora ramorum, an exotic generalist pathogen. Phytophthora ramorum causes leaf blight and...
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Is timing the key to good fruit phenolics?: year 2
USDA-ARS?s Scientific Manuscript database
Despite a century of research, we still lack a concrete, mechanistic understanding of solar radiation and temperature effects on anthocyanin accumulation and composition, crucial for red wine grapes. Our aim was to elucidate the mechanistic response to microclimate of anthocyanin metabolism in Vitis...
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Is solar radiation a key to good red wine grape anthocyanin?
USDA-ARS?s Scientific Manuscript database
Despite a century of research, we still lack a concrete, mechanistic understanding of solar radiation and temperature effects on anthocyanin accumulation and composition, crucial for red wine grapes. Our aim was to elucidate the mechanistic response to microclimate of anthocyanin metabolism in Viti...
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Small differences in temperature interact with solar radiation to alter anthocyanin in grapes
USDA-ARS?s Scientific Manuscript database
Despite a century of research, we still lack a concrete, mechanistic understanding of solar radiation and temperature effects on anthocyanin accumulation and composition, crucial for red wine grapes. Our aim was to elucidate the mechanistic response to microclimate of anthocyanin metabolism in Viti...
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Basic results of medical examinations of Soyuz spacecraft crew members
NASA Technical Reports Server (NTRS)
Gurovskiy, N. N.; Yegorov, A. D.; Kakurin, L. I.; Nefedov, Y. G.
1975-01-01
Weightlessness, hypokinesia and intense activity of crew members caused changes in human physiological functions during prolonged space flight as expressed in unusual diurnal rhythms. Microclimate, radiation and the nervous emotional state were not of significance in emergence of human body response reactions.
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USDA-ARS?s Scientific Manuscript database
The microclimate within western cotton (Gossypium spp.) seems favorable for the western tarnished plant bug (Lygus hesperus Knight) provided adequate soil moisture is available. Diminishing water supplies and increasing costs in the West will likely change irrigation practices and induce at least p...
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Measurement of landing mosquito density on humans
USDA-ARS?s Scientific Manuscript database
In conventional vector surveillance systems, adult mosquito density and the rate of human-mosquito contact is estimated from the mosquito numbers captured in mechanical traps. However, the design of the traps, their placement in the habitat and operating time, microclimate, and other environmental ...
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RELATIONSHIPS OF NATURAL ENEMIES AND NON-PREY FOODS
USDA-ARS?s Scientific Manuscript database
There are very few entomophagous species so maladapted as to rely on prey as their sole nutritional resource. Although a rich source of nutrients, prey/host availability to predators and parasitoids is restricted temporally by ephemeral population dynamics, spatial differences in microclimate, struc...
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The effect of cropping systems and irrigation management on development of potato early blight
USDA-ARS?s Scientific Manuscript database
Crop and soil management may modify canopy and belowground microclimate. However, their effects on potential development and control of early blight are not well documented. Crop management systems [Status Quo (SQ), Soil Conserving (SC), Soil Improving (SI), Disease Suppressive (DS), and Continuou...
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Use of CFD modelling for analysing air parameters in auditorium halls
NASA Astrophysics Data System (ADS)
Cichowicz, Robert
2017-11-01
Modelling with the use of numerical methods is currently the most popular method of solving scientific as well as engineering problems. Thanks to the use of computer methods it is possible for example to comprehensively describe the conditions in a given room and to determine thermal comfort, which is a complex issue including subjective sensations of the persons in a given room. The article presents the results of measurements and numerical computing that enabled carrying out the assessment of environment parameters, taking into consideration microclimate, temperature comfort, speeds in the zone of human presence and dustiness in auditory halls. For this purpose measurements of temperature, relative humidity and dustiness were made with the use of a digital microclimate meter and a laser dust particles counter. Thanks to the above by using the application DesignBuilder numerical computing was performed and the obtained results enabled determining PMV comfort indicator in selected rooms.
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Raman spectroscopy detection of biomolecules in biocrusts from differing environmental conditions.
Miralles, I; Jorge-Villar, S E; van Wesemael, B; Lázaro, R
2017-01-15
Lichens and cyanobacteria colonize inhospitable places covering a wide climate range due to their different survival strategies, such as the synthesis of protective biomolecules. The effect of ecological factors on the synthesis of biomolecules has not been widely analysed. This study aimed to assess the effects of four factors (species, microclimate, seasonality and hydration state) and their interactions on the biomolecule frequency detected by Raman Spectroscopy. We included cyanobacterial biocrusts, and the lichens Diploschistes diacapsis, Squamarina lentigera, and Lepraria isidiata; two contrasted microclimates (typical and marginal), two contrasted seasons (hot and dry vs cool and wet) and two hydration states (dry and wet). "Species" was the most influential factor in the identity and frequency of the main biomolecules. Microclimatic differences in the range of the local specific habitats only influenced the biomolecules in cyanobacteria. There was a quadruple interaction among the factors, the effects being different mainly depending on the species. At D. diacapsis, the production of their main biomolecules depended on microclimate, although it also depended on seasonality. Nevertheless, in L. isidiata and S. lentigera microclimatic differences did not significantly affect the production of biomolecules. In the lichen species, the microhabitats exposed to relatively larger incident radiation did not show significantly larger relative frequency of photoprotective biomolecules. No clear connection between higher production of oxalates and drier microhabitats was found, suggesting that the synthesis of oxalates is not related to water reserve strategy. The pros and cons of monitor biomolecules in biocrust by Raman spectrometry were also discussed. Copyright © 2016. Published by Elsevier B.V.
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Human thermal comfort conditions and urban planning in hot-humid climates—The case of Cuba
NASA Astrophysics Data System (ADS)
Rodríguez Algeciras, José Abel; Coch, Helena; De la Paz Pérez, Guillermo; Chaos Yeras, Mabel; Matzarakis, Andreas
2016-08-01
Climate regional characteristics, urban environmental conditions, and outdoors thermal comfort requirements of residents are important for urban planning. Basic studies of urban microclimate can provide information and useful resources to predict and improve thermal conditions in hot-humid climatic regions. The paper analyzes the thermal bioclimate and its influence as urban design factor in Cuba, using Physiologically Equivalent Temperature (PET). Simulations of wind speed variations and shade conditions were performed to quantify changes in thermal bioclimate due to possible modifications in urban morphology. Climate data from Havana, Camagüey, and Santiago of Cuba for the period 2001 to 2012 were used to calculate PET with the RayMan model. The results show that changes in meteorological parameters influence the urban microclimate, and consequently modify the thermal conditions in outdoors spaces. Shade is the predominant strategy to improve urban microclimate with more significant benefits in terms of PET higher than 30 °C. For climatic regions such as the analyzed ones, human thermal comfort can be improved by a wind speed modification for thresholds of PET above 30 °C, and by a wind speed decreases in conditions below 26 °C. The improvement of human thermal conditions is crucial for urban sustainability. On this regards, our study is a contribution for urban designers, due to the possibility of taking advantage of results for improving microclimatic conditions based on urban forms. The results may enable urban planners to create spaces that people prefer to visit, and also are usable in the reconfiguration of cities.
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Human thermal comfort conditions and urban planning in hot-humid climates-The case of Cuba.
Rodríguez Algeciras, José Abel; Coch, Helena; De la Paz Pérez, Guillermo; Chaos Yeras, Mabel; Matzarakis, Andreas
2016-08-01
Climate regional characteristics, urban environmental conditions, and outdoors thermal comfort requirements of residents are important for urban planning. Basic studies of urban microclimate can provide information and useful resources to predict and improve thermal conditions in hot-humid climatic regions. The paper analyzes the thermal bioclimate and its influence as urban design factor in Cuba, using Physiologically Equivalent Temperature (PET). Simulations of wind speed variations and shade conditions were performed to quantify changes in thermal bioclimate due to possible modifications in urban morphology. Climate data from Havana, Camagüey, and Santiago of Cuba for the period 2001 to 2012 were used to calculate PET with the RayMan model. The results show that changes in meteorological parameters influence the urban microclimate, and consequently modify the thermal conditions in outdoors spaces. Shade is the predominant strategy to improve urban microclimate with more significant benefits in terms of PET higher than 30 °C. For climatic regions such as the analyzed ones, human thermal comfort can be improved by a wind speed modification for thresholds of PET above 30 °C, and by a wind speed decreases in conditions below 26 °C. The improvement of human thermal conditions is crucial for urban sustainability. On this regards, our study is a contribution for urban designers, due to the possibility of taking advantage of results for improving microclimatic conditions based on urban forms. The results may enable urban planners to create spaces that people prefer to visit, and also are usable in the reconfiguration of cities.
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Raman spectroscopy detection of biomolecules in biocrusts from differing environmental conditions
NASA Astrophysics Data System (ADS)
Miralles, I.; Jorge-Villar, S. E.; van Wesemael, B.; Lázaro, R.
2017-01-01
Lichens and cyanobacteria colonize inhospitable places covering a wide climate range due to their different survival strategies, such as the synthesis of protective biomolecules. The effect of ecological factors on the synthesis of biomolecules has not been widely analysed. This study aimed to assess the effects of four factors (species, microclimate, seasonality and hydration state) and their interactions on the biomolecule frequency detected by Raman Spectroscopy. We included cyanobacterial biocrusts, and the lichens Diploschistes diacapsis, Squamarina lentigera, and Lepraria isidiata; two contrasted microclimates (typical and marginal), two contrasted seasons (hot and dry vs cool and wet) and two hydration states (dry and wet). ;Species; was the most influential factor in the identity and frequency of the main biomolecules. Microclimatic differences in the range of the local specific habitats only influenced the biomolecules in cyanobacteria. There was a quadruple interaction among the factors, the effects being different mainly depending on the species. At D. diacapsis, the production of their main biomolecules depended on microclimate, although it also depended on seasonality. Nevertheless, in L. isidiata and S. lentigera microclimatic differences did not significantly affect the production of biomolecules. In the lichen species, the microhabitats exposed to relatively larger incident radiation did not show significantly larger relative frequency of photoprotective biomolecules. No clear connection between higher production of oxalates and drier microhabitats was found, suggesting that the synthesis of oxalates is not related to water reserve strategy. The pros and cons of monitor biomolecules in biocrust by Raman spectrometry were also discussed.
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Deforestation, fire susceptibility, and potential tree responses to fire in the eastern Amazon
DOE Office of Scientific and Technical Information (OSTI.GOV)
Uhl, C.; Kauffman, J.B.
1990-04-01
In the state of Para, Brazil, in the eastern Amazon, the authors studied the potential for sustained fire events within four dominant vegetation cover types (undisturbed rain forest, selectively logged forest, second-growth forest, and open pasture), by measuring fuel availability, microclimate, and rates of fuel moisture loss. They also estimated the potential tree mortality that might result from a wide-scale Amazon forest fire by measuring the thermal properties of bark for all trees in a 5-ha stand of mature forest, followed by measurements of heat flux through bark during simulated fires. In pastures the average midday temperature was almost 10{degree}Cmore » greater and the average midday relative humidity was 30% lower than in primary forest. The most five-prone ecosystem was the open pasture followed by selectively logged forest, second growth forest, and undisturbed rain forest in which sustained combustion was not possible even after prolonged rainless periods. Even though the autogenic factors in primary forest of the eastern Amazon create a microclimate that virtually eliminates the probability of fire, they are currently a common event in disturbed areas of Amazonia. As many as 8 {times} 10{sup 6} ha burned in the Amazon Basin of Brazil in 1987 alone. In terms of current land-use patterns, altered microclimates, and fuel mass, there are also striking similarities between the eastern Amazon and East Kalimantan, Indonesia (the site of recent rain forest wildfires that burned 3.5 {times} 10{sup 6} ha).« less
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Gotsch, Sybil G; Davidson, Kenneth; Murray, Jessica G; Duarte, Vanessa J; Draguljić, Danel
2017-12-01
Tropical Montane Cloud Forests (TMCFs) are important ecosystems to study and preserve because of their high biodiversity and critical roles in local and regional ecosystem processes. TMCFs may be particularly affected by changes in climate because of the narrow bands of microclimate they occupy and the vulnerability of TMCF species to projected increases in cloud base heights and drought. A comprehensive understanding of the structure and function of TMCFs is lacking and difficult to attain because of variation in topography within and across TMCF sites. This causes large differences in microclimate and forest structure at both large and small scales. In this study, we estimated the abundance of the entire epiphyte community in the canopy (bryophytes, herbaceous vascular plants, woody epiphytes, and canopy dead organic matter) in six sites. In each of the sites we installed a complete canopy weather station to link epiphyte abundance to a number of microclimatic parameters. We found significant differences in epiphyte abundance across the sites; epiphyte abundance increased with elevation and leaf wetness, but decreased as vapor pressure deficit (VPD) increased. Epiphyte abundance had the strongest relationship with VPD; there were differences in VPD that could not be explained by elevation alone. By measuring this proxy of canopy VPD, TMCF researchers will better understand differences in microclimate and plant community composition across TMCF sites. Incorporating such information in comparative studies will allow for more meaningful comparisons across TMCFs and will further conservation and management efforts in this ecosystem. © 2017 Botanical Society of America.
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Field windbreaks for bioenergy production and carbon sequestration
USDA-ARS?s Scientific Manuscript database
Tree windbreaks are a multi-benefit land use with the ability to mitigate climate change by modifying the local microclimate for improved crop growth and sequestering carbon in soil and biomass. Agroforestry practices are also being considered for bioenergy production by direct combustion or produci...
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J.J. Rykken; A.R. Moldenke; D.H. Olson
2007-01-01
Invertebrate communities were characterized in unmanaged headwaters, and the effects of clearcutting without buffers and with buffers of approximately 30 m was examined. A near-stream community was distinct and largely retained by the buffers. Elevation, location, and microclimate were predictors of community structure.
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[Hygienic evaluation of health risk for female workers of stock-raising enterprise].
Iusupova, N Z; Shamsiiarov, N N; Dautov, F F
2012-01-01
The article presents results of study concerning work conditions of female workers engaged into stock-raising enterprises of Tatarstan Republic. Findings are that major occupational hazards in the female workers are unfavorable microclimate, chemical hazards contaminating ambient air of workplace and high noise level.
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USDA-ARS?s Scientific Manuscript database
One of our three program goals for this USDA-ARS-CRIS project is to determine the effects of vineyard and vine microclimate (sunlight, temperature, humidity, etc) upon fruit development, vine productivity, and fruit quality, particularly phenolic compounds. Plant phenolics are important due to their...
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ERIC Educational Resources Information Center
Moore, Gary T.
1998-01-01
Examines five issues related to child care facility design: (1) siting the building, outdoor play, and service areas; (2) creating favorable microclimates; (3) developmentally appropriate play yards; (4) pedestrian access and site circulation; and (5) vehicular access and parking away from pedestrians and play. (KB)
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Some Basics for Teaching and Evaluating Energy Conservation in the Home
ERIC Educational Resources Information Center
McColl, Robert W.
1978-01-01
Examines methods for determining thermal efficiency and measuring heat loss in the home. Suggests ways to conserve energy based upon (1) climatic environment and its impact on a structure, (2) physical location of buildings and their microclimate, and (3) behavior modification of the inhabitants. (Author)
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Katherine L. Martin; P. Charles Goebel
2011-01-01
Hemlock woolly adelgid (HWA) is an invasive insect causing widespread mortality in eastern hemlock (Tsuga canadensis [L.] Carr; hereafter "hemlock") throughout eastern forests. Hemlock is a foundation species, regulating ecosystem structure and function (e.g., microclimate, nutrient cycling). Across the central and southern Appalachians,...
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[Sanitary epidemiologic safety and technical regulations on railway transport].
Leksin, A G
2009-01-01
The author necessitated that requirements on sanitary and epidemiologic safety of life support systems for engine driver cabin (microclimate maintainance system, protection from vibration and noise, illumination, workplace ergonomics, etc) should be included into technical regulations for railway vehicles, both newly constructed and modernized.
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Effect of topography on microclimate in southwestern Wisconsin.
Richard S. Sartz
1972-01-01
Ridge and coulee terrain has little effect on point rainfall, but snowpack accumulation is affected by degree of slope and aspect. North slopes accumulate about 50% more snow. Soil water depletion is little affected by aspect. South slopes receive more insulation than north slopes, but temperature differences are slight and may result more from wind differences than...
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Microclimate Cooling and the Aircrew Chemical Defense Ensemble
1986-05-01
subjects on approximately 50 percent of the ZITA test trials in order to increase the subjects workload. The 11 tititett^^ ZITA was administered...included the standard deviations of vertical airspeed (VSI) and aircraft roll (ROLL). Time on trial was not measured in this 3 £3 22...34.■ " - ".* V "> "«"> * » "J * -"«" * * s *JI ’ • v« » .^ .’ VBJ-JI ’^M^M M* rafruilWAXrj|"J(AJir^Alinjrrwrwr»..rwrru<rBfrwrrir.. only HAAT trials with
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Solar energy microclimate as determined from satellite observations
NASA Technical Reports Server (NTRS)
Vonder Haar, T. H.; Ellis, J. S.
1975-01-01
A method is presented for determining solar insolation at the earth's surface using satellite broadband visible radiance and cloud imagery data, along with conventional in situ measurements. Conventional measurements are used to both tune satellite measurements and to develop empirical relationships between satellite observations and surface solar insolation. Cloudiness is the primary modulator of sunshine. The satellite measurements as applied in this method consider cloudiness both explicitly and implicitly in determining surface solar insolation at space scales smaller than the conventional pyranometer network.
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Impact of agroforestry plantings for bioenergy production on soil organic carbon
USDA-ARS?s Scientific Manuscript database
Tree windbreaks are an attractive multiple-benefit land use through their ability to mitigate climate change by modifying the local microclimate to improve crop growth and by sequestering carbon in the soil and tree biomass. Recently, such agroforestry practices are also being considered for their b...
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Microclimatic performance of a free-air warming and CO2 enrichment experiment in windy Wyoming, USA
USDA-ARS?s Scientific Manuscript database
In order to predict and plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (warming, elevated CO2) on the ecologically critical experimental plot microclimate. During three years of an eight year stu...
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Impact of water deficit on volatile composition of grapes and wine
USDA-ARS?s Scientific Manuscript database
Availability of water has become an increased concern for agriculture, including wine and wine grape production. Water status will directly affect plant nutrient uptake, and change vine canopy size. The canopy size may alter the microclimate within the vine canopy and change vine physiology. The cha...
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Hartwell H Welsh Jr; Garth R. Hodgson; Nancy E. Karraker
2005-01-01
We examined differences in riparian and aquatic environments within the three dominant vegetation patch types of the Mattole River watershed, a 789-km2 mixed conifer-deciduous (hardwood) forest and grassland-dominated landscape in northwestern California, USA. Riparian and aquatic environments, and particularly microclimates therein, influence...
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Afrane, Yaw A.; Little, Tom J.; Lawson, Bernard W.; Githeko, Andrew K.
2008-01-01
We investigated the effects of deforestation on microclimates and sporogonic development of Plasmodium falciparum parasites in Anopheles gambiae mosquitoes in an area of the western Kenyan highland prone to malaria epidemics. An. gambiae mosquitoes were fed with P. falciparum–infected blood through membrane feeders. Fed mosquitoes were placed in houses in forested and deforested areas in a highland area (1,500 m above sea level) and monitored for parasite development. Deforested sites had higher temperatures and relative humidities, and the overall infection rate of mosquitoes was increased compared with that in forested sites. Sporozoites appeared on average 1.1 days earlier in deforested areas. Vectorial capacity was estimated to be 77.7% higher in the deforested site than in the forested site. We showed that deforestation changes microclimates, leading to more rapid sporogonic development of P. falciparum and to a marked increase of malaria risk in the western Kenyan highland. PMID:18826815
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The Influence of Roof Material on Diurnal Urban Canyon Breathing
NASA Astrophysics Data System (ADS)
Abuhegazy, Mohamed; Yaghoobian, Neda
2017-11-01
Improvements in building energy use, air quality in urban canyons and in general urban microclimates require understanding the complex interaction between urban morphology, materials, climate, and inflow conditions. Review of the literature indicates that despite a long history of valuable urban microclimate studies, more comprehensive approaches are needed to address energy, and heat and flow transport in urban areas. In this study, a more comprehensive simulation of the diurnally varying street canyon flow and associated heat transport is numerically investigated, using Large-eddy Simulation (LES). We use computational modeling to examine the impact of diurnal variation of the heat fluxes from urban surfaces on the air flow and temperature distribution in street canyons with a focus on the role of roof materials and their temperature footprints. A detailed building energy model with a three-dimensional raster-type geometry provides urban surface heat fluxes as thermal boundary conditions for the LES to determine the key aero-thermodynamic factors that affect urban street ventilation.
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Shimazaki, Yasuhiro; Matsutani, Toshiki; Satsumoto, Yayoi
2016-07-01
Comfort is an important concept in footwear design. The microclimate inside footwear contributes to the perception of thermal comfort. To investigate the effect of ventilation on microclimate formation inside footwear, experiments with subjects were conducted at four gait speeds with three different footwear sizes. Skin temperature, metabolism, and body mass were measured at approximately 25 °C and 50% relative humidity, with no solar radiation and a calm wind. The footwear occupancy and ventilation rate were also estimated, with the latter determined using the tracer gas method. The experimental results revealed that foot movement, metabolism, evaporation, radiation, convection, and ventilation were the main factors influencing the energy balance for temperature formation on the surface of the foot. The cooling effect of ventilation on the arch temperature was observed during gait. The significance of the amount of air space and ventilation on the improvement in the thermal comfort of footwear was clarified. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.
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Small group gender ratios impact biology class performance and peer evaluations
Cotner, Sehoya
2018-01-01
Women are underrepresented in science, technology, engineering, and mathematics (STEM) disciplines. Evidence suggests the microclimate of the classroom is an important factor influencing female course grades and interest, which encourages retention of women in STEM fields. Here, we test whether the gender composition of small (8–9 person) learning groups impacts course performance, sense of social belonging, and intragroup peer evaluations of intellectual contributions. Across two undergraduate active learning courses in introductory biology, we manipulated the classroom microclimate by varying the gender ratios of learning groups, ranging from 0% female to 100% female. We found that as the percent of women in groups increased, so did overall course performance for all students, regardless of gender. Additionally, women assigned higher peer- evaluations in groups with more women than groups with less women. Our work demonstrates an added benefit of the retention of women in STEM: increased performance for all, and positive peer perceptions for women. PMID:29614091
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Biogeography of photoautotrophs in the high polar biome
Pointing, Stephen B.; Burkhard Büdel; Convey, Peter; Gillman, Len N.; Körner, Christian; Leuzinger, Sebastian; Vincent, Warwick F.
2015-01-01
The global latitudinal gradient in biodiversity weakens in the high polar biome and so an alternative explanation for distribution of Arctic and Antarctic photoautotrophs is required. Here we identify how temporal, microclimate and evolutionary drivers of biogeography are important, rather than the macroclimate features that drive plant diversity patterns elsewhere. High polar ecosystems are biologically unique, with a more central role for bryophytes, lichens and microbial photoautotrophs over that of vascular plants. Constraints on vascular plants arise mainly due to stature and ontogenetic barriers. Conversely non-vascular plant and microbial photoautotroph distribution is correlated with favorable microclimates and the capacity for poikilohydric dormancy. Contemporary distribution also depends on evolutionary history, with adaptive and dispersal traits as well as legacy influencing biogeography. We highlight the relevance of these findings to predicting future impacts on diversity of polar photoautotrophs and to the current status of plants in Arctic and Antarctic conservation policy frameworks. PMID:26442009
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Thermal environment and sleep in winter shelter-analogue settings
NASA Astrophysics Data System (ADS)
Mochizuki, Yosuke; Maeda, Kazuki; Nabeshima, Yuki; Tsuzuki, Kazuyo
2017-10-01
We aimed to examine sleep in shelter-analogue settings in winter to determine the sleep and environmental conditions in evacuation shelters. Twelve young healthy students took part in the sleep study of two nights for seven hours from 0 AM to 7 AM in a gymnasium. One night the subject used a pair of futons and on the other the subject used emergency supplies consisting of four blankets and a set of portable partitions. Air temperature, humidity were measured around the sleeping subjects through the night. Sleep parameters, skin temperature, microclimate temperature, rectal temperature, and heart rate of the subjects were continuously measured and recorded during the sleeping period. The subjects completed questionnaires relating to thermal comfort and subjective sleep before and after sleep. The sleep efficiency indices were lower when the subjects slept using the blankets. As the microclimate temperature between the human body and blanket was lower, mean skin temperature was significantly lower in the case of blankets.
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Small group gender ratios impact biology class performance and peer evaluations.
Sullivan, Lauren L; Ballen, Cissy J; Cotner, Sehoya
2018-01-01
Women are underrepresented in science, technology, engineering, and mathematics (STEM) disciplines. Evidence suggests the microclimate of the classroom is an important factor influencing female course grades and interest, which encourages retention of women in STEM fields. Here, we test whether the gender composition of small (8-9 person) learning groups impacts course performance, sense of social belonging, and intragroup peer evaluations of intellectual contributions. Across two undergraduate active learning courses in introductory biology, we manipulated the classroom microclimate by varying the gender ratios of learning groups, ranging from 0% female to 100% female. We found that as the percent of women in groups increased, so did overall course performance for all students, regardless of gender. Additionally, women assigned higher peer- evaluations in groups with more women than groups with less women. Our work demonstrates an added benefit of the retention of women in STEM: increased performance for all, and positive peer perceptions for women.
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Zarzo, Manuel; Fernández-Navajas, Angel; García-Diego, Fernando-Juan
2011-01-01
We describe the performance of a microclimate monitoring system that was implemented for the preventive conservation of the Renaissance frescoes in the apse vault of the Cathedral of Valencia, that were restored in 2006. This system comprises 29 relative humidity (RH) and temperature sensors: 10 of them inserted into the plaster layer supporting the fresco paintings, 10 sensors in the walls close to the frescoes and nine sensors measuring the indoor microclimate at different points of the vault. Principal component analysis was applied to RH data recorded in 2007. The analysis was repeated with data collected in 2008 and 2010. The resulting loading plots revealed that the similarities and dissimilarities among sensors were approximately maintained along the three years. A physical interpretation was provided for the first and second principal components. Interestingly, sensors recording the highest RH values correspond to zones where humidity problems are causing formation of efflorescence. Recorded data of RH and temperature are discussed according to Italian Standard UNI 10829 (1999). PMID:22164100
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John A. Parrotta
1993-01-01
Forest plantations established on degraded sites can accelerate natural succession through their effects on vegetation structure, microclimate, and soils. Spatial and temporal patterns of secondary forest species regeneration were studied in permanent quadrats in Albizia lebbek planta1ion plots and control areas at a degraded coastal pasture in...
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Forest dynamics following eastern hemlock mortality in the southern Appalachians
Chelcy R. Ford; Katherine J. Elliott; Barton D. Clinton; Brian D. Kloeppel; James M. Vose
2011-01-01
Understanding changes in community composition caused by invasive species is critical for predicting effects on ecosystem function, particularly when the invasive threatens a foundation species. Here we focus on dynamics of forest structure, composition and microclimate, and how these interact in southern Appalachian riparian forests following invasion by hemlock...
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On-Going Research at Slippery Rock University.
ERIC Educational Resources Information Center
Chase, Craig
1985-01-01
Summarizes eight research studies in the field of outdoor/environmental education being completed at Slippery Rock University in 1985. Topics include isolation among National Park Service rangers, school participation in recycling programs, the use of trees to modify microclimates in West African urban centers, and evaluation of environmental…
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Two subspecies and a hybrid of big sagebrush: Comparison of respiration and growth characteristics
L. D. Hansen; L. K. Farnsworth; N. K. Itoga; A. Nicholson; H. L. Summers; M. C. Whitsitt; E. D. McArthur
2008-01-01
Environmental temperatures and growth and respiratory characteristics of natural populations of two subspecies and a hybrid of sagebrush (Artemisia tridentata) that grow on a single hillside were measured to test a hypothesis that adaptation to microclimate temperature patterns restricts these taxa to their native locations and that plant-endophyte...
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Johnson, Joseph S; Lacki, Michael J
2013-07-01
Many small mammals are heterothermic endotherms capable of maintaining an elevated core body temperature or reducing their thermoregulatory set point to enter a state of torpor. Torpor can confer substantial energy savings, but also incurs ecological costs, such as hindering allocation of energy towards reproduction. We placed temperature-sensitive radio transmitters on 44 adult Rafinesque's big-eared bats (Corynorhinus rafinesquii) and deployed microclimate dataloggers inside 34 day roosts to compare the use of torpor by different sex and reproductive classes of bats during the summer. We collected 324 bat-days of skin-temperature data from 36 females and 4 males. Reproductive females employed fewer torpor bouts per day than non-reproductive females and males (P < 0.0001), and pregnant and lactating females had higher average (P < 0.0001) and minimum (P < 0.0001) skin temperatures than non-reproductive females. Pregnant females spent less time torpid (P < 0.0001) than non-reproductive females, but lactating females used relatively deep, long torpor bouts. Microclimates varied inside tree species with different configurations of entrances to the roost cavity (P < 0.0001). Bats spent more time torpid when roosting in water tupelo (Nyssa aquatica) trees possessing only a basal entrance to the cavity (P = 0.001). Of the tree species used as roosts, water tupelo cavities exhibited the least variable daytime and nighttime temperatures. These data demonstrate that use of summer torpor is not uniform among sex and reproductive classes in Rafinesque's big-eared bat, and variation in microclimate among tree roosts due to species and structural characteristics facilitates the use of different thermoregulatory strategies in these bats.
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NASA Astrophysics Data System (ADS)
Korbut, Vadim; Voznyak, Orest; Sukholova, Iryna; Myroniuk, Khrystyna
2017-12-01
The abstract is to The article is devoted to the decision of actual task of air distribution efficiency increasing with the help of swirl and spread air jets to provide normative parameters of air in the production apartments. The mathematical model of air supply with swirl and spread air jets in that type of apartments is improved. It is shown that for reachin of air distribution maximal efficiency it is necessary to supply air by air jets, that intensively extinct before entering into a working area. Simulation of air flow performed with the help of CFD FLUENT (Ansys FLUENT). Calculations of the equation by using one-parameter model of turbulence Spalart-Allmaras are presented. The graphical and the analytical dependences on the basis of the conducted experimental researches, which can be used in subsequent engineering calculations, are shown out. Dynamic parameters of air flow that is created due to swirl and spread air jets at their leakage at variable regime and creation of dynamic microclimate in a room has been determined. Results of experimental investigations of air supply into the room by air distribution device which creates swirl air jets for creation more intensive turbulization air flow in the room are presented. Obtained results of these investigations give possibility to realize engineer calculations of air distribution with swirl air jets. The results of theoretical researches of favourable influence of dynamic microclimate to the man are presented. When using dynamic microclimate, it's possible to decrease conditioning and ventilation system expenses. Human organism reacts favourably on short lasting deviations from the rationed parameters of air environment.
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Rockweit, Jeremy T.; Franklin, Alan B.; Bakken, George S.; Gutiérrez, R. J.
2012-01-01
Many bird species do not make their own nests; therefore, selection of existing sites that provide adequate microclimates is critical. This is particularly true for owls in north temperate climates that often nest early in the year when inclement weather is common. Spotted owls use three main types of nest structures, each of which are structurally distinct and may provide varying levels of protection to the eggs or young. We tested the hypothesis that spotted owl nest configuration influences nest microclimate using both experimental and observational data. We used a wind tunnel to estimate the convective heat transfer coefficient (hc) of eggs in 25 potential nest configurations that mimicked 2 nest types (top-cavity and platform nests), at 3 different wind speeds. We then used the estimates of hc in a biophysical heat transfer model to estimate how long it would take unattended eggs to cool from incubation temperature (∼36°C) to physiological zero temperature (PZT; ∼26°C) under natural environmental conditions. Our results indicated that the structural configuration of nests influences the cooling time of the eggs inside those nests, and hence, influences the nest microclimate. Estimates of time to PZT ranged from 10.6 minutes to 33.3 minutes. Nest configurations that were most similar to platform nests always had the fastest egg cooling times, suggesting that platform nests were the least protective of those nests we tested. Our field data coupled with our experimental results suggested that nest choice is important for the reproductive success of owls during years of inclement weather or in regions characterized by inclement weather during the nesting season. PMID:22859993
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Modelled and field measurements of biogenic hydrocarbon emissions from a Canadian deciduous forest
NASA Astrophysics Data System (ADS)
Fuentes, J. D.; Wang, D.; Den Hartog, G.; Neumann, H. H.; Dann, T. F.; Puckett, K. J.
The Biogenic Emission Inventory System (BEIS) used by the United States Environmental Protection Agency (Lamb et al., 1993, Atmospheric Environment21, 1695-1705; Pierce and Waldruff, 1991, J. Air Waste Man. Ass.41, 937-941) was tested for its ability to provide realistic microclimate descriptions within a deciduous forest in Canada. The microclimate description within plant canopies is required because isoprene emission rates from plants are strongly influenced by foliage temperature and photosynthetically active radiation impinging on leaves while monoterpene emissions depend primarily on leaf temperature. Model microclimate results combined with plant emission rates and local biomass distribution were used to derive isoprene and α-pinene emissions from the deciduous forest canopy. In addition, modelled isoprene emission estimates were compared to measured emission rates at the leaf level. The current model formulation provides realistic microclimatic conditions for the forest crown where modelled and measured air and foliage temperature are within 3°C. However, the model provides inadequate microclimate characterizations in the lower canopy where estimated and measured foliage temperatures differ by as much as 10°C. This poor agreement may be partly due to improper model characterization of relative humidity and ambient temperature within the canopy. These uncertainties in estimated foliage temperature can lead to underestimates of hydrocarbon emission estimates of two-fold. Moreover, the model overestimates hydrocarbon emissions during the early part of the growing season and underestimates emissions during the middle and latter part of the growing season. These emission uncertainties arise because of the assumed constant biomass distribution of the forest and constant hydrocarbon emission rates throughout the season. The BEIS model, which is presently used in Canada to estimate inventories of hydrocarbon emissions from vegetation, underestimates emission
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Fire and riparian ecosystems in landscapes of the western USA
Kathleen A. Dwire; J. Boone Kauffman
2003-01-01
Despite the numerous values of riparian areas and the recognition of fire as a critical natural disturbance, few studies have investigated the behavior, properties, and influence of natural fire in riparian areas of the western USA. Riparian areas frequently differ from adjacent uplands in vegetative composition and structure, geomorphology, hydrology, microclimate,...
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Topography-mediated controls on local vegetation phenology estimated from MODIS vegetation index
Taehee Hwang; Conghe Song; James Vose; Lawrence Band
2011-01-01
Forest canopy phenology is an important constraint on annual water and carbon budgets, and responds to regional interannual climate variation. In steep terrain, there are complex spatial variations in phenology due to topographic influences on microclimate, community composition, and available soil moisture. In this study, we investigate spatial patterns of phenology...
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Nazrullaeva, M F; Alekseev, A N
1991-01-01
The efficacy of minihygrometers in the study of bed microclimate (a shelter of dust ticks) has been assessed. Maximum difference between minihygrometer and August's psychrometer parameters reaches 0.5%. In all shelters of ticks humidity at night was higher than in the premises, which demonstrates the efficacy of the method used.
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Barton D. Clinton
2003-01-01
Small canopy openings often alter understory microclimate, leading to changes in forest structure and composition. It is generally accepted that physical changes in the understory (i.e., microclimatic) due to canopy removal drive changes in basic forest processes, particularly seedling recruitment which is intrinsically linked to soil moisture availability, light and,...
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Resource selection by an ectothermic predator in a dynamic thermal landscape
Andrew D. George; Grant M. Connette; Frank R. Thompson; John Faaborg
2017-01-01
Predicting the effects of global climate change on species interactions has remained difficult because there is a spatiotemporal mismatch between regional climate models and microclimates experienced by organisms. We evaluated resource selection in a predominant ectothermic predator using a modeling approach that permitted us to assess the importance of habitat...
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Cathryn H. Greenberg; Christopher E. Moorman; Amy L. Raybuck; Chad Sundol; Tara L. Keyser; Janis Bush; Dean M. Simon; Gordon S. Warburton
2016-01-01
Forest restoration efforts commonly employ silvicultural methods that alter light and competition to influence species composition. Changes to forest structure and microclimate may adversely affect some taxa (e.g., terrestrial salamanders), but positively affect others (e.g., early successional birds). Salamanders are cited as indicators of ecosystem health because of...
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Elizabeth A Nauertz; Thomas R. Crow; John Zasada; Ronald M. Teclaw
2004-01-01
Temperature, light, wind, and precipitation were measured in the understory of managed and unmanaged northern hardwood forests in the Upper Peninsula of Michigan from 1995 through 2001. These measurements provide a baseline of information to compare the microclimate under managed and unmanaged conditions. Extreme climatic events may influence growth and development...
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Diversity and distribution of ant communities in Puerto Rico
J.A. Torres
1984-01-01
I studied ants in upland tropical forest, grassland and agricultural land in San Lorenzo, Puerto Rico, to uncover factors responsible for the distribution and number of species in these communities. Observations, laboratory studies and field experiments were used. Microclimate influenced the distributions of Pheidole fallax, Solenopsis geminata and Monomorium ebeninum...
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S.M. Eagan; C.T. Hunsaker; C.R. Dolanc; M.E. Lynch; C.R. Johnson
2007-01-01
The Kings River Experimental Watershed (KREW) is now in its third year of data collection on eight small perennial watersheds. We are collecting meteorology, stream discharge, sediment load, water chemistry, shallow soil water chemistry, vegetation, macro-invertebrate, stream microclimate, and air quality data. This paper primarily examines discharge and sediment data...
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Forest vegetation of eastern Washington and northern Idaho
R. Daubenmire; Jean B. Daubenmire
1968-01-01
The forest vegetation of the northern Rocky Mountains is potentially a rather simple mosaic determined by macroclimate, microclimate, soil fertility and soil drainage. In actuality, however, the vegetation consists mainly of a wide variety of intergrading, disturbance-induced communities that are difficult to treat except as developmental series related to...
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Adapting forest management to climate change using bioclimate models with topographic drivers
Gerald E. Rehfeldt; James J. Worrall; Suzanne B. Marchetti; Nicholas L. Crookston
2015-01-01
Bioclimate models incorporating topographic predictors as surrogates for microclimate effects are developed for Populus tremuloides and Picea engelmannii to provide the fine-grained specificity to local terrain required for adapting management of three Colorado (USA) national forests (1.28 million ha) and their periphery to climate change. Models were built with the...
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Thermal regimes of Mexican spotted owl nest stands
Joseph L. Ganey
2004-01-01
To evaluate the hypothesis that spotted owls (Strix occidentalis) select habitats with cool microclimates to avoid high daytime temperatures, I sampled thermal regimes in nest areas used by Mexican spotted owls (S. o. lucida) in northern Arizona. I sampled air temperature at 30-min intervals in 30 pairs of nest and random sites...
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Do silvicultural practices to restore oaks affect salamanders in the short term?
Amy L. Raybuck; Christopher E. Moorman; Sarah R. Fritts; Cathryn H. Greenberg; Christopher S. Deperno; Dean M. Simon; Gordon S. Warburton
2015-01-01
Salamanders are an important ecological component of eastern hardwood forests and may be affected by natural or silvicultural disturbances that alter habitat structure and associated microclimate. From May to August in 2008 (pre- treatment) and 2011 (post-treatment), we evaluated the response of salamanders to three silvicultural practices designed to promote oak...
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A review of factors affecting cave climates for hibernating bats in temperate North America
Roger W. Perry
2013-01-01
The fungal pathogen Geomyces destructans, which causes white-nose syndrome in bats, thrives in the cold and moist conditions found in caves where bats hibernate. To aid managers and researchers address this disease, an updated and accessible review of cave hibernacula and cave microclimates is presented. To maximize energy savings and reduce...
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Timothy B. Harrington; Robert A. Slesak; Stephen H. Schoenholtz
2013-01-01
Logging debris remaining after timber harvest can modify the microclimate and growing conditions for forest regeneration. Debris also can influence tree seedlings indirectly through its effects on development of competing vegetation, although the mechanisms are poorly understood. At two sites in Washington and Oregon (USA) that differed in availability of soil water...
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ERIC Educational Resources Information Center
Lyons, Zachary
2010-01-01
Issues related to supporting the language of schooling have become important social and educational policy concerns in Ireland. This article reports on a three-year investigation of the micro-climate of English language support provision in 70 post-primary schools since 2007 and highlights potential points of leverage in the educational system for…
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Chapter 10. Dynamics of subalpine forests
Dennis H. Knight
1994-01-01
The boreal owl's fairly specific habitat requirements restrict its range in the conterminous U.S. to subalpine forests (see Chapter 9). These forests provide tree cavities, uncrusted snow that facilitates preying on small mammals, and cool microclimates essential for summer roosting. Such forests also provide habitat for the owl's prey which consists...
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Oscar J. Abelleira Martinez
2011-01-01
The African tulip tree, Spathodea campanulata, dominates many post-agricultural secondary forests in the moist tropics. Some consider these novel forests have no ecological value, yet they appear to restore ecosystem processes on degraded sites. This study describes the litterfall mass and seasonality, canopy phenology, and microclimate of S. campanulata forests on...
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Cross-scale modeling of surface temperature and tree seedling establishment inmountain landscapes
Dingman, John; Sweet, Lynn C.; McCullough, Ian M.; Davis, Frank W.; Flint, Alan L.; Franklin, Janet; Flint, Lorraine E.
2013-01-01
Abstract: Introduction: Estimating surface temperature from above-ground field measurements is important for understanding the complex landscape patterns of plant seedling survival and establishment, processes which occur at heights of only several centimeters. Currently, future climate models predict temperature at 2 m above ground, leaving ground-surface microclimate not well characterized. Methods: Using a network of field temperature sensors and climate models, a ground-surface temperature method was used to estimate microclimate variability of minimum and maximum temperature. Temperature lapse rates were derived from field temperature sensors and distributed across the landscape capturing differences in solar radiation and cold air drainages modeled at a 30-m spatial resolution. Results: The surface temperature estimation method used for this analysis successfully estimated minimum surface temperatures on north-facing, south-facing, valley, and ridgeline topographic settings, and when compared to measured temperatures yielded an R2 of 0.88, 0.80, 0.88, and 0.80, respectively. Maximum surface temperatures generally had slightly more spatial variability than minimum surface temperatures, resulting in R2 values of 0.86, 0.77, 0.72, and 0.79 for north-facing, south-facing, valley, and ridgeline topographic settings. Quasi-Poisson regressions predicting recruitment of Quercus kelloggii (black oak) seedlings from temperature variables were significantly improved using these estimates of surface temperature compared to air temperature modeled at 2 m. Conclusion: Predicting minimum and maximum ground-surface temperatures using a downscaled climate model coupled with temperature lapse rates estimated from field measurements provides a method for modeling temperature effects on plant recruitment. Such methods could be applied to improve projections of species’ range shifts under climate change. Areas of complex topography can provide intricate microclimates that may
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NASA Astrophysics Data System (ADS)
Moody, M.; Bailey, B.; Stoll, R., II
2017-12-01
Understanding how changes in the microclimate near individual plants affects the surface energy budget is integral to modeling land-atmosphere interactions and a wide range of near surface atmospheric boundary layer phenomena. In urban areas, the complex geometry of the urban canopy layer results in large spatial deviations of turbulent fluxes further complicating the development of models. Accurately accounting for this heterogeneity in order to model urban energy and water use requires a sub-plant level understanding of microclimate variables. We present analysis of new experimental field data taken in and around two Blue Spruce (Picea pungens) trees at the University of Utah in 2015. The test sites were chosen in order study the effects of heterogeneity in an urban environment. An array of sensors were placed in and around the conifers to quantify transport in the soil-plant-atmosphere continuum: radiative fluxes, temperature, sap fluxes, etc. A spatial array of LEMS (Local Energy Measurement Systems) were deployed to obtain pressure, surrounding air temperature and relative humidity. These quantities are used to calculate the radiative and turbulent fluxes. Relying on measurements alone is insufficient to capture the complexity of microclimate distribution as one reaches sub-plant scales. A spatially-explicit radiation and energy balance model previously developed for deciduous trees was extended to include conifers. The model discretizes the tree into isothermal sub-volumes on which energy balances are performed and utilizes incoming radiation as the primary forcing input. The radiative transfer component of the model yields good agreement between measured and modeled upward longwave and shortwave radiative fluxes. Ultimately, the model was validated through an examination of the full energy budget including radiative and turbulent fluxes through isolated Picea pungens in an urban environment.
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Differences in physical growth of Aymara and Quechua children living at high altitude in Peru.
de Meer, K; Bergman, R; Kusner, J S; Voorhoeve, H W
1993-01-01
Physical growth of Amerindian children living in two Aymara and three Quechua peasant communities in the Andean highlands of southern Peru (altitude 3,810-3,840 m) was studied, taking into account differences in the microclimate, agronomic situation, and sociodemographic variables. Anthropometric measurements were taken in 395 children aged under 14 years of age in a sample of 151 families in these communities, who were surveyed for sociodemographic variables as well. Data on the land system were available for 77 families. In comparison with reference populations from the United States (NCHS) and The Netherlands, stature, weight, head circumference, and midupper arm circumference (but not weight for stature) in the sample children were reduced. Growth retardation increased after the age of 1 year. Stature and weight in the present sample were very similar compared with previously published data on growth of rural Aymara children living near Lake Titicaca in Bolivia. Head circumference, midupper arm circumference, and weight for stature were significantly larger in Aymara children compared with Quechua children. Land was significantly more fragmented in Aymara compared with Quechua families, but amount of land owned was not different. Perinatal and infant mortality was elevated in Aymara vs. Quechua communities. Most families in Aymara communities used protected drinking water. One Quechua community had a severe microclimate, grim economic outlook, and weak social cohesion. Children in this community showed significant reductions in weight and midupper arm circumference compared with their peers in the other communities. We conclude that (presumably nutritionally mediated) intervillage and Aymara-Quechua differences in childhood physical growth existed in this rural high-altitude population in Peru and were associated with microclimate and the village economy, sociodemographic factors, and differences in the land system.
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NASA Astrophysics Data System (ADS)
Sheridan, Gary; nyman, petter; Duff, Tom; Baillie, Craig; Bovill, William; Lane, Patrick; Tolhurst, Kevin
2015-04-01
The prediction of fuel moisture content is important for estimating the rate of spread of wildfires, the ignition probability of firebrands, and for the efficient scheduling of prescribed fire. The moisture content of fine surface fuels varies spatially at large scales (10's to 100's km) due to variation in meteorological variables (eg. temperature, relative humidity, precipitation). At smaller scales (100's of metres) in steep topography spatial variability is attributed to topographic influences that include differences in radiation due to aspect and slope, differences in precipitation, temperature and relative humidity due to elevation, and differences in soil moisture due to hillslope drainage position. Variable forest structure and canopy shading adds further to the spatial variability in surface fuel moisture. In this study we aim to combine daily 5km resolution gridded weather data with 20m resolution DEM and vegetation structure data to predict the spatial variability of fine surface fuels in steep topography. Microclimate stations were established in south east Australia to monitor surface fine fuel moisture continuously (every 15 minutes) using newly developed instrumented litter packs, in addition to temperature and relative humidity measurements inside the litter pack, and measurement of precipitation and energy inputs above and below the forest canopy. Microclimate stations were established across a gradient of aspect (5 stations), drainage position (7 stations), elevation (15 stations), and canopy cover conditions (6 stations). The data from this extensive network of microclimate stations across a broad spectrum of topographic conditions is being analysed to enable the downscaling of gridded weather data to spatial scales that are relevant to the connectivity of wildfire fuels and to the scheduling and outcome of prescribed fires. The initial results from the first year of this study are presented here.
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NASA Astrophysics Data System (ADS)
Coombes, Martin A.; Naylor, Larissa A.; Viles, Heather A.; Thompson, Richard C.
2013-11-01
As well as their destructive roles, plants, animals and microorganisms contribute to geomorphology and ecology via direct and indirect bioprotection, which can reduce weathering and erosion. For example, indirect bioprotection can operate via biotic influences on microclimate whereby physical decay processes associated with fluctuations in temperature and moisture (salt crystallization, thermal fatigue and wetting-drying), are limited. In the intertidal zone, the spatial and temporal distribution of macroalgae (seaweeds) is patchy, related to physical and ecological conditions for colonization and growth, and the nature and frequency of natural and anthropogenic disturbance. We examined the influence of seaweed canopies (Fucus spp.) on near-surface microclimate and, by implication, on conditions for mechanical rock decay and under-canopy ecology. Monitoring on hard artificial coastal structures in South West England, UK, built from limestone and concrete showed that both the range and maxima of daily summertime temperatures were significantly lower, by an average of 56% and 25%, respectively, in areas colonized by seaweed compared to experimentally cleared areas. Short-term microclimatic variability (minutes-hours) was also significantly reduced, by an average of 78% for temperature and 71% for humidity, under algal canopies during low-tide events. Using seaweed as an example, we develop a conceptual model of the relationship between biological cover and microclimate in the intertidal zone. Disturbance events that remove or drastically reduce seaweed cover mediate shifts between relatively stable and unstable states with respect to mechanical decay and ecological stress associated with heat and desiccation. In urban coastal environments where disturbance may be frequent, facilitating the establishment and recovery of canopy-forming species on rocks and engineered structures could enhance the durability of construction materials as well as support conservation
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Dale L. Bartos; Gordon D. Booth
1994-01-01
Temperature measurements were made to better understand the role of microclimate on mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae), activity as a result of thinning lodgepole pine stands. Sampling was done over 61 days on the north slope of the Unita Mountain Range in northeastern Utah. Principal components analysis was applied to all...
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California's coast redwood in New Zealand
Tom Gaman
2012-01-01
New Zealanders are making a significant effort to develop their forest industry to benefit from rapid growth exhibited by Sequoia sempervirens on both the North Island and South Island. US and New Zealand forest products companies have established redwood plantations in the past decade, and have found that microclimate, site preparation, soil chemistry, fertilization...
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Defoliation and mortality patterns in forests silviculturally managed for gypsy moth
Kurt W. Gottschalk; Rose-Marie Muzika
1995-01-01
Mixed hardwood forests of the Appalachian region support one of the most diverse communities of woody plants in North America, but the composition and relative dominance of the forest changes substantially with slight changes in physiography, soil type, or microclimate. Composition of oak and other species highly preferred by the gypsy moth determines the...
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Xiao Chen; Deborah Page-Dumroese; Ruiheng Lv; Weiwei Wang; Guolei Li; Yong Liu
2014-01-01
Thinning alters litter quality and microclimate under forests. Both of these two changes after thinning induce alterations of litter decomposition rates and nutrient cycling. However, a possible interaction between these two changes remains unclear. We placed two types of litter (LN, low N concentration litter; HN, high N concentration litter) in a Chinese pine (Pinus...
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P.J. Peper; E.G. McPherson; S.M. Mori
2001-01-01
Although the modeling of energy-use reduction, air pollution uptake, rainfall interception, and microclimate modification associated with urban trees depends on data relating diameter at breast height (dbh) , crown height, crown diameter, and leaf area to tree age or dbh, scant information is available for common municipal tree species . I n this study , tree height ,...
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P.W. Rundel; C.I. Millar
2016-01-01
Alpine ecosystems are typically defined as those areas occurring above treeline, while recognizing that alpine ecosystems at a local scale may be found below this boundary for reasons including geology, geomorphology, and microclimate. The lower limit of the alpine ecosystems, the climatic treeline, varies with latitude across California, ranging from about 3500 m in...
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Design of outdoor urban spaces for thermal comfort
Harriet J. Plumley
1977-01-01
Microclimates in outdoor urban spaces may be modified by controlling the wind and radiant environments in these spaces. Design guidelines were developed to specify how radiant environments may be selected or modified to provide conditions for thermal comfort. Fanger's human-thermal-comfort model was used to determine comfortable levels of radiant-heat exchange for...
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Effects of forest fire and logging on forest degradation in Mongolia
Yeong Dae Park; Don Koo Lee; Jamsran Tsogtbaatar; John A. Stanturf
2010-01-01
Forests in Mongolia have been severely degraded by forest fire and exploitive logging. This study investigate changes in vegetation and soil properties after forest fire or clearfelling. Microclimate conditions such as temperature and relative humidity (RH) changed drastically after forest fire or logging; temperature increased 1.6-1.7 ºC on average, whereas...
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Hurricanes, coral reefs and rainforests: resistance, ruin and recovery in the Caribbean
Lugo, Ariel E.; Rogers, Caroline S.; Nixon, Scott W.
2000-01-01
The coexistence of hurricanes, coral reefs, and rainforests in the Caribbean demonstrates that highly structured ecosystems with great diversity can flourish in spite of recurring exposure to intense destructive energy. Coral reefs develop in response to wave energy and resist hurricanes largely by virtue of their structural strength. Limited fetch also protects some reefs from fully developed hurricane waves. While storms may produce dramatic local reef damage, they appear to have little impact on the ability of coral reefs to provide food or habitat for fish and other animals. Rainforests experience an enormous increase in wind energy during hurricanes with dramatic structural changes in the vegetation. The resulting changes in forest microclimate are larger than those on reefs and the loss of fruit, leaves, cover, and microclimate has a great impact on animal populations. Recovery of many aspects of rainforest structure and function is rapid, though there may be long-term changes in species composition. While resistance and repair have maintained reefs and rainforests in the past, human impacts may threaten their ability to survive.
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Davey, C.A.; Pielke, R.A.; Gallo, K.P.
2006-01-01
There is currently much attention being given to the observed increase in near-surface air temperatures during the last century. The proper investigation of heating trends, however, requires that we include surface heat content to monitor this aspect of the climate system. Changes in heat content of the Earth's climate are not fully described by temperature alone. Moist enthalpy or, alternatively, equivalent temperature, is more sensitive to surface vegetation properties than is air temperature and therefore more accurately depicts surface heating trends. The microclimates evident at many surface observation sites highlight the influence of land surface characteristics on local surface heating trends. Temperature and equivalent temperature trend differences from 1982-1997 are examined for surface sites in the Eastern U.S. Overall trend differences at the surface indicate equivalent temperature trends are relatively warmer than temperature trends in the Eastern U.S. Seasonally, equivalent temperature trends are relatively warmer than temperature trends in winter and are relatively cooler in the fall. These patterns, however, vary widely from site to site, so local microclimate is very important. ?? 2006 Elsevier B.V. All rights reserved.
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Analysis of the systems of ventilation of residential houses of Ukraine and Estonia
NASA Astrophysics Data System (ADS)
Savchenko, Olena; Zhelykh, Vasyl; Voll, Hendrik
2017-12-01
The most common ventilation system in residential buildings in Ukraine is natural ventilation. In recent years, due to increased tightness of structures, an increase in the content of synthetic finishing materials in them, the quality of microclimate parameters deteriorated. One of the measures to improve the parameters of indoor air in residential buildings is the use of mechanical inflow and exhaust ventilation system. In this article the regulatory documents concerning the design of ventilation systems in Ukraine and Estonia and the requirements for air exchange in residential buildings are considered. It is established that the existing normative documents in Ukraine are analogous to European norms, which allow design the system of ventilation of residential buildings according to European standards. However, the basis for the design of ventilation systems in Ukraine is the national standards, in which mechanical ventilation, unfortunately, is provided only for the design of high-rise buildings. To maintain acceptable microclimate parameters in residential buildings, it is advisable for designers to apply the requirements for designing ventilation systems in accordance with European standards.
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Challenges in pressure ulcer prevention.
Dealey, Carol; Brindle, C Tod; Black, Joyce; Alves, Paulo; Santamaria, Nick; Call, Evan; Clark, Michael
2015-06-01
Although this article is a stand-alone article, it sets the scene for later articles in this issue. Pressure ulcers are considered to be a largely preventable problem, and yet despite extensive training and the expenditure of a large amount of resources, they persist. This article reviews the current understanding of pressure ulcer aetiology: pressure, shear and microclimate. Individual risk factors for pressure ulceration also need to be understood in order to determine the level of risk of an individual. Such an assessment is essential to determine appropriate prevention strategies. The main prevention strategies in terms of reducing pressure and shear and managing microclimate are studied in this article. The problem of pressure ulceration related to medical devices is also considered as most of the standard prevention strategies are not effective in preventing this type of damage. Finally, the possibility of using dressings as an additional preventive strategy is raised along with the question: is there enough evidence to support their use? © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.
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USAF Physiological Studies of Personal Microclimate Cooling: A Review
1993-05-01
53 vi 11h. Thermal comfort ratings during continuous work. AC = Ambient Air Cooling; NC = No Cooling...43 10b Thermal Comfort (TC) and Rating of Perceived Exertion (RPE) at the End of 45-Min Work Cycles in...47 10d Thermal Comfort (TC) and Ratings of Perceived Exertion (RPE) at the End o! 30
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An experimental study of microclimate at Coliseum (Rome, Italy)
NASA Astrophysics Data System (ADS)
de Simone, Sara; di Menno, Ivo; Malvestuto, Vincenzo; Gallo, Veronica; Rafanelli, Claudio; Poscolieri, Maurizio
2010-05-01
The study of the causes of the deterioration of monuments and architectural heritage has been carried out by means of a campaign of measures aimed at the assessment of horizontal and vertical gradients of temperature and humidity. These gradients are needed both to assess the sensible and latent heat fluxes in the monument walls and to show the efficiency of the various possible mechanisms of deposition of pollutants, leading among others to the genesis of the "black" crusts. The paper will show the preliminary results of the measurement campaign performed during autumn-winter of 2002 and 2003 at the northern walls of the Amphitheatrum Flavium (Roman Coliseum). This results have provided evidence of well-defined correlations among the three components of wind speed and anti-correlation between temperature and humidity on the surface of the monument stone.
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Demonstration of the gypsy moth energy budget microclimate model
D. E. Anderson; D. R. Miller; W. E. Wallner
1991-01-01
The use of a "User friendly" version of "GMMICRO" model to quantify the local environment and resulting core temperature of GM larvae under different conditions of canopy defoliation, different forest sites, and different weather conditions was demonstrated.
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Robert J. Warren
2010-01-01
⢠The ubiquitous transition of plant communities across slope aspects is a welldescribed, but rarely tested, ecological dynamic. Aspect position is often used as a proxy for microclimate changes in moisture, light and temperature, but these abiotic drivers are seldom decoupled and very rarely manipulated across slope aspects. ⢠To investigate the mechanisms...
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Tera E. Lewandowski; Jodi A. Forrester; David J. Mladenoff; Anthony W. D' Amato; Brian J. Palik
2016-01-01
Intensive forest biomass harvesting, or the removal of harvesting slash (woody debris from tree branches and tops) for use as biofuel, has the potential to negatively affect the soil microbial community (SMC) due to loss of carbon and nutrient inputs from the slash, alteration of the soil microclimate, and increased nutrient leaching. These effects could result in...
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Megan McGroddy; Whendee L. Silver
2000-01-01
We used a humid tropical elevation gradient to examine the relationships among climate, edaphic conditions, belowground carbon storage, and soil respiration rates. We also compared open and closed canopy sites to increase the range of microclimate conditions sampled along the gradient, and determine the effects of canopy openings on C and P storage, and C dynamics....
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The urban FIA inventory: plot design, data collection, data flow and processing
Tonya Lister; Mark Majewsky; Mark A. Hatfield; Angie Rowe; Bill Dunning; Chris Edgar; Tom Brandeis
2015-01-01
More than 80 percent of the U.S. population lives in urban areas and tree cover in these areas offers a wide range of environmental benefits including the provision of wildlife habitat, aesthetic appeal and visual barriers, microclimate control, water quality improvement, and air and noise pollution control. Recognizing the importance of urban forests, and with...
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Fekedulegn Desta; J.J. Colbert; James S. Rentch; Kurt W. Gottschalk
2004-01-01
This study evaluates and quantifies the variation in vegetation, plant nutrients, and microclimate across four topographic aspects in an Appalachian watershed (39°39'43"N, 79°45'28"W). The study found that the north and east aspects were 27-50% more productive than the west and southwest aspects. Species groups that showed strong...
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Watershed clearcutting and canopy arthropods
Barbara C. Reynolds; Timothy D. Schowalter; D.A. Crossley
2014-01-01
The southern Appalachian forests are home to myriad species of insects, spiders, and other arthropods. There are more than 4,000 invertebrate species know in the Great Smoky Mountains National Park , and easily a thousand insect species in the Coweeta basin alone. The forest environment, with its favorable microclimates and structural diversity, offers a large variety...
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Seasonal variation in nest placement of Abert's Towhees
Deborah M. Finch
1983-01-01
Several meteorological variables are known to influence the heat budgets of nesting birds (e.g., Walsberg and King 1978a, b). Such factors include air temperature, incident radiation, wind, and humidity. If the microclimate of the nest is unfavorable, parent birds may become inattentive, exposing eggs or nestlings to excessive heat or cold. They may then desert the...
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Paul E. Hennon; David V. D' Amore; Paul G. Schaberg; Dustin T. Wittwer; Colin S. Shanley
2012-01-01
The extensive mortality of yellow-cedar along more than 1000 kilometers of the northern Pacific coast of North America serves as a leading example of climate effects on a forest tree species. In this article, we document our approaches to resolving the causes of tree death, which we explain as a cascade of interacting topographic, forest-structure, and microclimate...
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Controlling solar light and heat in a forest by managing shadow sources
Howard G. Halverson; James L. Smith
1974-01-01
Control of solar light and heat to develop the proper growth environment is a desirable goal in forest management. The amount of sunlight and heat reaching the surface is affected by shadows cast by nearby objects, including trees. In timbered areas, the type of forest management practiced can help develop desired microclimates. The results depend on the size and...
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Soil Properties Related to Coniferous Seedling Height Growth in Northern Wisconsin
John J. Rawinski; James A. Bowles; Nonan V. Noste
1980-01-01
Soil properties (organic matter content, pH, texture, and microclimate) were related to early height growth of jack pine (Pinus banksiana, Lamb.), red pine (Pinus resinosa, Ait.), white spruce (Picea glauca, (Moench) Voss), and hybrid larch (Larix leptolepis x Larizx decidua) planted in northern Wisconsin. Based on 2-year height growth, jack pine and hybrid larch...
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Leaf litter is an important mediator of soil respiration in an oak-dominated forest
Jared L. DeForest; Jiquan Chen; Steve G. McNulty
2009-01-01
The contribution of the organic (O) horizon to total soil respiration is poorly understood even though it can represent a large source of uncertainty due to seasonal changes in microclimate and O horizon properties due to plant phenology. Our objectives were to partition the CO2 effluxes of litter layer and mineral soil from total soil...
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Parks and the urban heat island: A longitudinal study in Westfield, Massachusetts
Robert S. Bristow; Robert Blackie; Nicole Brown
2012-01-01
Urban landscapes often have warmer temperatures than the surrounding countryside, a phenomenon known as the urban heat island (UHI) effect. This study compares and contrasts temperatures across Westfield, Massachusetts, a moderate size New England city, and considers the influence that the cityâs parks and protected areas have on the local microclimate. The data show a...
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Centennial impacts of fragmentation on the canopy structure of tropical montane forest
Nicholas Vaughn; Greg Asner; Christian Giardina
2014-01-01
Fragmentation poses one of the greatest threats to tropical forests with short-term changes to the structure of forest canopies affecting microclimate, tree mortality, and growth. Yet the long-term effects of fragmentation are poorly understood because (1) most effects require many decades to materialize, but long-term studies are very rare, (2) the effects of edges on...
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Judith D. Springer; Amy E. M. Waltz; Peter Z. Fule; Margaret M. Moore; W. Wallace Covington
2001-01-01
The decision whether to seed with native species following restoration treatments should be based on existing vegetation, species present in or absent from the soil seed bank, past management history, microclimate conditions and soils. We installed three permanent monitoring plots in two areas (total 18.6 ha) at Mt. Trumbull, AZ. Trees were thinned and the sites burned...
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John C. Tappeiner
2013-01-01
Th inning stands (managing their densities) aff ects the development of trees and understory plants as individuals, as well as stand-level characteristics like structure, microclimate, and stand growth, habitat for various species, and fuel and potential fi re severity. Th ese characteristics and the rate of changes are aff ected by thinning severityâthe reduction in...
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[Characteristics of working conditions at metallurgy-related plants].
Egorova, A M
2008-01-01
Working conditions at more versus less advanced technology steel plants of the Volgograd Region are analyzed. The working conditions at the less advanced technology plants are referred to as a very high occupational risk. It is necessary to work out measures to lower the poor impact of microclimate, dust, noise, to improve illumination, and to regulate labor at steel plants.
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Effect of synthetic surfaces and vegetation in urban areas on human energy balance and comfort
Thomas F. Stark; David R. Miller
1977-01-01
The thermal balance of a standard man was quantified for a variety of urban and rural summer daytime microclimates. The resulting net heat-load data were correlated with the relative amounts of vegetation and synthetic materials at each site. By extrapolating these results, it is possible to estimate the expected heat load of a proposed development before it is built...
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Water-use efficiency of a poplar plantation in Northern China
Jie Zhou; Zhiqiang Zhang; Ge sun; Xianrui Fang; Tonggang Zha; Jiquan Chen; Asko Noormets; Junting Guo; Steve McNulty
2014-01-01
The water-use efficiency (WUE) of an ecosystemâdefined as the gross ecosystem production (GEP) divided by the evapotranspiration (ET)âis an important index for understanding the coupling of water and carbon and quantifying waterâcarbon trade-offs in forests. An open-path eddy covariance technique and a microclimate measurement system were deployed to investigate the...
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Technology Evaluation for an Advanced Individual Protection System (AIPS)
1992-12-01
this analysis are: time of operation, duration of thermal management, power consumed during operation, cooling/heating benefit , time between recharge...BRDEC) TOPICS: o individual power * batteries/engines/fuel cel!s POC: Wes Goodwin (NRDEC) TOPICS: * microclimate cooling e vapor compression cycles e...individual power 2.3 LITERATURE SEARCHES The literature searches began by reviewing Battelle in-house sources for useful reports. This included a
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Lydia P. Olander; F.N Scatena; Whendee L. Silver
1998-01-01
The impacts of road construction and the spread of exotic vegetation, which are common threats to upper elevation tropical forests, were evaluated in the subtropical cloud forests of Puerto Rico. The vegetation, soil and microclimate of 6-month-old road®lls, 35-year-old road®lls and mature forest with and without grass understories were compared. Recent road®lls had...
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NASA Astrophysics Data System (ADS)
Siegert, C. M.; Levia, D. F.
2010-12-01
Forest ecosystems provide a significant portion of fresh water to the hydrologic cycle through transpiration, the majority of which is supplied by saplings and mature trees. However, a smaller, yet measurable, proportion is also supplied by seedlings. The contribution of seedlings is dependent upon physiological characteristics of the species, whose range of habitat is ultimately controlled by microclimate. The objectives of this study were to (1) observe meteorological conditions of two forest microlimates and (2) assess the intra- and interspecific stomatal conductance and transpiration responses of naturally occurring seedlings of varying shade tolerance. Naturally established seedlings in a deciduous forest understory and an adjacent clearing were monitored throughout the 2008 growing season in southeastern Pennsylvania (39°49'N, 75°43'W). Clear spatial and temporal trends of stomatal conductance and transpiration were observed throughout this study. The understory microclimate conditions overall had a lower degree of variability and had consistently lower mean quantum flux density, air temperature, vapor pressure deficit, volumetric water content, and soil temperature than the clearing plot. Shade tolerant understory seedlings (Fagus grandifolia Ehrh. (American beech) and Prunus serotina L. (black cherry)) had significantly lower mean monthly rates of water loss (p = 0.05) than shade intolerant clearing seedlings (P. serotina and Liriodendron tulipifera L. (yellow poplar)). Additionally, water loss by shade grown P. serotina was significantly lower (p = 0.05) than by sun grown P. serotina. Significant intraspecific responses (p = 0.05) were also observed on a monthly basis, with the exception of L. tulipifera. These findings indicate that physiological differences, specifically shade tolerance, play an important role in determining rates of stomatal conductance and transpiration in tree seedlings. To a lesser degree, microclimate variability was also shown
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Distribution of a climate-sensitive species at an interior range margin
Ray, Chris; Beever, Erik; Rodhouse, Thomas J.
2016-01-01
Advances in understanding the factors that limit a species’ range, particularly in the context of climate change, have come disproportionately through investigations at range edges or margins. The margins of a species’ range might often correspond with anomalous microclimates that confer habitat suitability where the species would otherwise fail to persist. We addressed this hypothesis using data from an interior, climatic range margin of the American pika (Ochotona princeps), an indicator of relatively cool, mesic climates in rocky habitats of western North America. Pikas in Lava Beds National Monument, northeastern California, USA, occur at elevations much lower than predicted by latitude and longitude. We hypothesized that pika occurrence within Lava Beds would be associated primarily with features such as “ice caves” in which sub-surface ice persists outside the winter months. We used data loggers to monitor sub-surface temperatures at cave entrances and at non-cave sites, confirming that temperatures were cooler and more stable at cave entrances. We surveyed habitat characteristics and evidence of pika occupancy across a random sample of cave and non-cave sites over a 2-yr period. Pika detection probability was high (~0.97), and the combined occupancy of cave and non-cave sites varied across the 2 yr from 27% to 69%. Contrary to our hypothesis, occupancy was not higher at cave sites. Vegetation metrics were the best predictors of site use by pikas, followed by an edge effect and elevation. The importance of vegetation as a predictor of pika distribution at this interior range margin is congruent with recent studies from other portions of the species’ range. However, we caution that vegetation composition depends on microclimate, which might be the proximal driver of pika distribution. The microclimates available in non-cave crevices accessible to small animals have not been characterized adequately for lava landscapes. We advocate innovation in the
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Microclimatic Performance of a Free-Air Warming and CO2 Enrichment Experiment in Windy Wyoming, USA
LeCain, Daniel; Smith, David; Morgan, Jack; Kimball, Bruce A.; Pendall, Elise; Miglietta, Franco
2015-01-01
In order to plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (warming, elevated CO2) on the experimental plot microclimate. During three years of an eight year study with year-round feedback-controlled infra-red heater warming (1.5/3.0°C day/night) and growing season free-air CO2 enrichment (600 ppm) in the mixed-grass prairie of Wyoming, USA, we monitored soil, leaf, canopy-air, above-canopy-air temperatures and relative humidity of control and treated experimental plots and evaluated ecologically important temperature differentials. Leaves were warmed somewhat less than the target settings (1.1 & 1.5°C day/night) but soil was warmed more creating an average that matched the target settings extremely well both during the day and night plus the summer and winter. The site typically has about 50% bare or litter covered soil, therefore soil heat transfer is more critical than in dense canopy ecosystems. The Wyoming site commonly has strong winds (5 ms-1 average) and significant daily and seasonal temperature fluctuations (as much as 30°C daily) but the warming system was nearly always able to maintain the set temperatures regardless of abiotic variation. The within canopy-air was only slightly warmed and above canopy-air was not warmed by the system, therefore convective warming was minor. Elevated CO2 had no direct effect nor interaction with the warming treatment on microclimate. Relative humidity within the plant canopy was only slightly reduced by warming. Soil water content was reduced by warming but increased by elevated CO2. This study demonstrates the importance of monitoring the microclimate in manipulative field global change experiments so that critical physiological and ecological conclusions can be determined. Highly variable energy demand fluctuations showed that passive IR heater warming systems will not maintain desired warming for much of the
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Microclimatic performance of a free-air warming and CO₂ enrichment experiment in windy Wyoming, USA
DOE Office of Scientific and Technical Information (OSTI.GOV)
LeCain, Daniel; Smith, David; Morgan, Jack
In order to plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (warming, elevated CO₂) on the experimental plot microclimate. During three years of an eight year study with year-round feedback-controlled infra-red heater warming (1.5/3.0°C day/night) and growing season free-air CO₂ enrichment (600 ppm) in the mixed-grass prairie of Wyoming, USA, we monitored soil, leaf, canopy-air, above-canopy-air temperatures and relative humidity of control and treated experimental plots and evaluated ecologically important temperature differentials. Leaves were warmed somewhat less than the target settings (1.1 & 1.5°C day/night)more » but soil was warmed more creating an average that matched the target settings extremely well both during the day and night plus the summer and winter. The site typically has about 50% bare or litter covered soil, therefore soil heat transfer is more critical than in dense canopy ecosystems. The Wyoming site commonly has strong winds (5 ms⁻¹ average) and significant daily and seasonal temperature fluctuations (as much as 30°C daily) but the warming system was nearly always able to maintain the set temperatures regardless of abiotic variation. The within canopy-air was only slightly warmed and above canopy-air was not warmed by the system, therefore convective warming was minor. Elevated CO₂ had no direct effect nor interaction with the warming treatment on microclimate. Relative humidity within the plant canopy was only slightly reduced by warming. Soil water content was reduced by warming but increased by elevated CO₂. This study demonstrates the importance of monitoring the microclimate in manipulative field global change experiments so that critical physiological and ecological conclusions can be determined. Highly variable energy demand fluctuations showed that passive IR heater warming systems will not maintain desired warming
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Microclimatic performance of a free-air warming and CO₂ enrichment experiment in windy Wyoming, USA
LeCain, Daniel; Smith, David; Morgan, Jack; ...
2015-02-06
In order to plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (warming, elevated CO₂) on the experimental plot microclimate. During three years of an eight year study with year-round feedback-controlled infra-red heater warming (1.5/3.0°C day/night) and growing season free-air CO₂ enrichment (600 ppm) in the mixed-grass prairie of Wyoming, USA, we monitored soil, leaf, canopy-air, above-canopy-air temperatures and relative humidity of control and treated experimental plots and evaluated ecologically important temperature differentials. Leaves were warmed somewhat less than the target settings (1.1 & 1.5°C day/night)more » but soil was warmed more creating an average that matched the target settings extremely well both during the day and night plus the summer and winter. The site typically has about 50% bare or litter covered soil, therefore soil heat transfer is more critical than in dense canopy ecosystems. The Wyoming site commonly has strong winds (5 ms⁻¹ average) and significant daily and seasonal temperature fluctuations (as much as 30°C daily) but the warming system was nearly always able to maintain the set temperatures regardless of abiotic variation. The within canopy-air was only slightly warmed and above canopy-air was not warmed by the system, therefore convective warming was minor. Elevated CO₂ had no direct effect nor interaction with the warming treatment on microclimate. Relative humidity within the plant canopy was only slightly reduced by warming. Soil water content was reduced by warming but increased by elevated CO₂. This study demonstrates the importance of monitoring the microclimate in manipulative field global change experiments so that critical physiological and ecological conclusions can be determined. Highly variable energy demand fluctuations showed that passive IR heater warming systems will not maintain desired warming
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The critical role of fire in catchment coevolution in South Eastern Australia
NASA Astrophysics Data System (ADS)
Nyman, P.; Inbar, A.; Lane, P. N. J.; Sheridan, G. J.
2016-12-01
Temperate south east Australian forested uplands are characterised by complex spatial patterns in forest types, soils and fire regimes, even within areas with similar geologies and landscape position. Preliminary measurements and experiments suggest that positive and negative feedbacks between the vegetation, fuels, fire frequency and soil erosion may control the coevolution of these observed system states. Here we propose the hypotheses that in this landscape post-fire soil erosion has played a dominant role in the coevolved system-state combinations of standing biomass, fire frequency and soil depth. To test the hypothesis a 1D simulation model was developed that links together an ecohydrological model to drive the biomass production and water and energy partitioning, a stochastic fire model that is controlled by climate, fuel load and moisture conditions, and a geomorphic model that controls soil production and fluvial and diffusive sediment transport rates. The model was calibrated to the range of existing observed quasi-equalibrium system-states of soil depth, standing biomass, fuel loading and fire frequency using field measurements from 12 instrumented eco-hydrologic microclimate research sites. The long-term partitioning of rainfall into evaporation, transpiration, and streamflow was calibrated against field and literature values. Fuel moisture and micro-climate variables were calibrated to the field microclimate stations. The calibrated model was able to reasonably replicate the observed quasi-equilibrium system-states and hydrologic outputs using current climate forcings operating over a 10,000 year period, providing confidence in the model structure and performance. The model was then used to test the hypothesis stated above, by alternatively including or excluding the post fire erosion process. An alternate hypothesis, whereby the observed system states are dominated by climate related differences in soil production rates was also tested in this way
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NASA Astrophysics Data System (ADS)
Li Heng, Su; Chow, Winston
2017-04-01
Human thermal comfort research is important as climate discomfort can adversely affect both health and work productivity in cities; however, such biometeorological work in low-latitude urban areas is still relatively unstudied hitherto. In the tropical metropolis of Singapore, a suite of policies have been implemented aimed at improving environmental sustainability via increasing car-free commutes and pedestrian movement during work/school journeys, with the consequence that individuals will likely have increased personal exposure through a variety of spaces (and climates) during typical daily activities. As such, research into exploring the thermal (dis)comfort experienced during pedestrian movements across these indoor, outdoor and transitional (semi-outdoor) spaces would yield interesting applied biometerological insights. This pilot study thus investigates how pedestrian thermal comfort varies spatially across a university campus, and how the physical intensity of pedestrian travel affects thermal comfort across these spaces. Over a 10-week period, we profiled six students for both their objective and subjective pedestrian thermal comfort during traverses across different spaces. Data were obtained through use of (a.) of a heat stress sensor, (b.) a fitness tracker, and (b.) a questionnaire survey to record traverse measurements of the microclimate, their physiological data, and their perceived microclimate comfort respectively. Measured climate and physiological data were used to derive commonly-used thermal comfort indices like wet-bulb globe temperature (WBGT) and physiological equivalent temperature (PET). Further, interviews were conducted with all six subjects at the end of the fieldwork period to ascertain details on individual acclimatization behavior and adaptation strategies. The results indicate that (a.) more than 50% of the microclimatic conditions within each indoor, semi-outdoor, and outdoor space exceeded heat stress thresholds of both PET and
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Pincebourde, Sylvain; Murdock, Courtney C; Vickers, Mathew; Sears, Michael W
2016-07-01
When predicting the response of organisms to global change, models use measures of climate at a coarse resolution from general circulation models or from downscaled regional models. Organisms, however, do not experience climate at such large scales. The climate heterogeneity over a landscape and how much of that landscape an organism can sample will determine ultimately the microclimates experienced by organisms. This past few decades has seen an important increase in the number of studies reporting microclimatic patterns at small scales. This synthesis intends to unify studies reporting microclimatic heterogeneity (mostly temperature) at various spatial scales, to infer any emerging trends, and to discuss the causes and consequences of such heterogeneity for organismal performance and with respect to changing land use patterns and climate. First, we identify the environmental drivers of heterogeneity across the various spatial scales that are pertinent to ectotherms. The thermal heterogeneity at the local and micro-scales is mostly generated by the architecture or the geometrical features of the microhabitat. Then, the thermal heterogeneity experienced by individuals is modulated by behavior. Second, we survey the literature to quantify thermal heterogeneity from the micro-scale up to the scale of a landscape in natural habitats. Despite difficulties in compiling studies that differ much in their design and aims, we found that there is as much thermal heterogeneity across micro-, local and landscape scales, and that the temperature range is large in general (>9 °C on average, and up to 26 °C). Third, we examine the extent to which urban habitats can be used to infer the microclimatic patterns of the future. Urban areas generate globally drier and warmer microclimatic patterns and recent evidence suggest that thermal traits of ectotherms are adapted to them. Fourth, we explore the interplay between microclimate heterogeneity and the behavioral thermoregulatory
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Under-canopy microclimate within sand dunes in the Negev Desert
NASA Astrophysics Data System (ADS)
Kidron, Giora J.
2010-10-01
SummaryScattered shrubs are a common phenomenon in many arid landscapes. Once established, shrubs are known to create "islands of fertility", i.e., preferential habitats for annuals and animals. In an attempt to characterize the physical conditions prevailing under the shrub, radiation, temperatures and soil moisture (0-40 cm) following rain were measured during 1993-1995 at the shaded under-canopy (UC) and at the exposed inter-shrub habitat (EXP) of two pairs of shrubs located at the north- and south-facing slopes of dunes in the Nizzana research site, western Negev Desert, Israel. In addition, the soil organic matter (SOM) and the fine (silt and clay) content (FC) were also measured. Whereas the differences in the amounts of SOM and FC were small, daylight temperatures at UC were substantially lower (6-15 °C), subsequently resulting in extended time during which the UC habitat remained wet. Moisture was retained for up to 10.5-42.6% longer at UC in comparison to EXP, mainly explained by the shading effect. SOM was found to explain only 8.6-19.6% of the results. By shading, shrubs in the Negev Desert may thus provide relatively wetter conditions for annuals, rendering them an advantage over inter-shrub habitats at this harsh arid environment.
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Effects of Vegetation Microclimate on Larval Cattle Fever Tick Survival
USDA-ARS?s Scientific Manuscript database
Cattle Fever Ticks (CFT), Rhipicephalus annulatus and R. microplus, have been a threat to the livestock industry for many years. These ticks are vectors of cattle fever, a disease produced by the hemoparasite Babesia bovis and B. bigemina. Laboratory research on CFT larval survival has shown that co...
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Body Temperature Versus Microclimate Selection in Heat Stressed Dairy Cows
USDA-ARS?s Scientific Manuscript database
The purpose of this study is to characterize the thermoregulatory responses of unrestrained heat-stressed dairy cows within a freestall environment using fan and spray configurations for cooling cows while lying or standing. An experimental treatment sprayed individual cows lying in freestalls from ...
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Microclimate predicts within-season distribution dynamics of montane forest birds
Sarah J.K. Frey; Adam S. Hadley; Matthew G. Betts; Mark Robertson
2016-01-01
Aim: Climate changes are anticipated to have pervasive negative effects on biodiversity and are expected to necessitate widespread range shifts or contractions. Such projections are based upon the assumptions that (1) species respond primarily to broad-scale climatic regimes, or (2) that variation in climate at fine spatial scales is less relevant at coarse spatial...
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Colored plastic mulch microclimates affect strawberry fruit yield and quality
NASA Astrophysics Data System (ADS)
Shiukhy, Saeid; Raeini-Sarjaz, Mahmoud; Chalavi, Vida
2015-08-01
Significant reduction of strawberry ( Fragaria × ananassa, Duch.) fruit yield and quality, as a consequence of conventional cultivation method, is common in the Caspian Sea region, Iran. Recently, growers started using plastic mulches to overcome these shortcomings. Plastic mulches have different thermal and radiation properties and could affect strawberry fruit yield and quality. In the present study, the effect of different colored plastic mulches (black, red, and white) along with conventional practice was tested on yield and quality of strawberry Camarosa cultivar, in a completely randomized block design. Colored plastic mulches had highly significant effect on fruit weight, size, and phytochemical contents. In the most harvest times, mean fruit weight was significantly higher in red plastic relative to white and control treatments. Total fruit weight of plastic mulches was not significantly different, while all were statistically higher than that of control. Fruit size significantly increased over red plastic mulch. Total fruit numbers over plastic mulches were significantly higher than that of control treatment. The content of phenolic compounds was similar between treatments, while anthocyanin content, IC50 value, and flavonoid content significantly were affected by colored plastics. In conclusion, colored plastic mulches could affect strawberry fruit weight and quality through altering strawberry thermal and radiation environment.
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Colored plastic mulch microclimates affect strawberry fruit yield and quality.
Shiukhy, Saeid; Raeini-Sarjaz, Mahmoud; Chalavi, Vida
2015-08-01
Significant reduction of strawberry (Fragaria × ananassa, Duch.) fruit yield and quality, as a consequence of conventional cultivation method, is common in the Caspian Sea region, Iran. Recently, growers started using plastic mulches to overcome these shortcomings. Plastic mulches have different thermal and radiation properties and could affect strawberry fruit yield and quality. In the present study, the effect of different colored plastic mulches (black, red, and white) along with conventional practice was tested on yield and quality of strawberry Camarosa cultivar, in a completely randomized block design. Colored plastic mulches had highly significant effect on fruit weight, size, and phytochemical contents. In the most harvest times, mean fruit weight was significantly higher in red plastic relative to white and control treatments. Total fruit weight of plastic mulches was not significantly different, while all were statistically higher than that of control. Fruit size significantly increased over red plastic mulch. Total fruit numbers over plastic mulches were significantly higher than that of control treatment. The content of phenolic compounds was similar between treatments, while anthocyanin content, IC(50) value, and flavonoid content significantly were affected by colored plastics. In conclusion, colored plastic mulches could affect strawberry fruit weight and quality through altering strawberry thermal and radiation environment.
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[Hygienic education in pupils from general educational establishments].
Mirskaia, N B
2009-01-01
The high prevalence of the major behavioral factors of a risk to health: violation of the study leisure regimen, violation of dietary pattern and quality, low motor activity, smoking, frequent alcohol abuse, drug taste, and deteriorated family microclimate, was revealed in middle and senior schoolchildren from Moscow, Kaliningrad, and Murmansk. Proposals are given to mold healthy lifestyle in adolescents and to optimize their hygienic education at general educational establishments.
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Army Field-Oriented S&T Experimentation Venues: A Comparative Analysis
2011-09-01
Microclimate Cooling Station (MCCS)). The Fort Benning AEWE provides the venue and the data collection and analysis. The costs to the S&T...forest, fields, etc.) and is designated as an Army experimental station with access to ground and an aerial fleet. Technology developers have optional...YTC), (2) tropical (the Tropic Regions Test Center, Panama Canal Zone), and (3) cold weather (CRTC, Bolio Lake Test Complex, AK. Special
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Spatial models reveal the microclimatic buffering capacity of old-growth forests
Frey, Sarah J. K.; Hadley, Adam S.; Johnson, Sherri L.; Schulze, Mark; Jones, Julia A.; Betts, Matthew G.
2016-01-01
Climate change is predicted to cause widespread declines in biodiversity, but these predictions are derived from coarse-resolution climate models applied at global scales. Such models lack the capacity to incorporate microclimate variability, which is critical to biodiversity microrefugia. In forested montane regions, microclimate is thought to be influenced by combined effects of elevation, microtopography, and vegetation, but their relative effects at fine spatial scales are poorly known. We used boosted regression trees to model the spatial distribution of fine-scale, under-canopy air temperatures in mountainous terrain. Spatial models predicted observed independent test data well (r = 0.87). As expected, elevation strongly predicted temperatures, but vegetation and microtopography also exerted critical effects. Old-growth vegetation characteristics, measured using LiDAR (light detection and ranging), appeared to have an insulating effect; maximum spring monthly temperatures decreased by 2.5°C across the observed gradient in old-growth structure. These cooling effects across a gradient in forest structure are of similar magnitude to 50-year forecasts of the Intergovernmental Panel on Climate Change and therefore have the potential to mitigate climate warming at local scales. Management strategies to conserve old-growth characteristics and to curb current rates of primary forest loss could maintain microrefugia, enhancing biodiversity persistence in mountainous systems under climate warming. PMID:27152339
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Merckx, Thomas; Serruys, Mélanie; Van Dyck, Hans
2015-04-01
Recent anthropogenic eutrophication has meant that host plants of nettle-feeding insects became quasi-omnipresent in fertile regions of Western Europe. However, host plant resource quality - in terms of microclimate and nutritional value - may vary considerably between the 'original' forest habitat and 'recent' agricultural habitat. Here, we compared development in both environmental settings using a split-brood design, so as to explore to what extent larval survival and adult morphology in the nettle-feeding butterfly Aglais urticae are influenced by the anthropogenic environment. Nettles along field margins had higher C/N ratios and provided warmer microclimates to larvae. Larvae developed 20% faster and tended to improve their survival rates, on the agricultural land compared to woodland. Our split-brood approach indicated plastic responses within families, but also family effects in the phenotypic responses. Adult males and females had darker wing pigmentation in the drier and warmer agricultural environment, which contrasts with the thermal melanism hypothesis. Developmental plasticity in response to this microclimatically different and more variable habitat was associated with a broader phenotypic parameter space for the species. Both habitat expansion and developmental plasticity are likely contributors to the ecological and evolutionary success of these nettle-feeding insects in anthropogenic environments under high nitrogen load.
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Merckx, Thomas; Serruys, Mélanie; Van Dyck, Hans
2015-01-01
Recent anthropogenic eutrophication has meant that host plants of nettle-feeding insects became quasi-omnipresent in fertile regions of Western Europe. However, host plant resource quality – in terms of microclimate and nutritional value – may vary considerably between the ‘original’ forest habitat and ‘recent’ agricultural habitat. Here, we compared development in both environmental settings using a split-brood design, so as to explore to what extent larval survival and adult morphology in the nettle-feeding butterfly Aglais urticae are influenced by the anthropogenic environment. Nettles along field margins had higher C/N ratios and provided warmer microclimates to larvae. Larvae developed 20% faster and tended to improve their survival rates, on the agricultural land compared to woodland. Our split-brood approach indicated plastic responses within families, but also family effects in the phenotypic responses. Adult males and females had darker wing pigmentation in the drier and warmer agricultural environment, which contrasts with the thermal melanism hypothesis. Developmental plasticity in response to this microclimatically different and more variable habitat was associated with a broader phenotypic parameter space for the species. Both habitat expansion and developmental plasticity are likely contributors to the ecological and evolutionary success of these nettle-feeding insects in anthropogenic environments under high nitrogen load. PMID:25926881
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Kumari, Priyanka; Woo, Cheolwoon; Yamamoto, Naomichi; Choi, Hong-Lim
2016-01-01
We examined the abundance, diversity and community composition of airborne fungi in swine houses during winter and summer seasons by using quantitative PCR and Illumina HiSeq sequencing of ITS1 region. The abundance of airborne fungi varied significantly only between seasons, while fungal diversity varied significantly both within and between seasons, with both abundance and diversity peaked in winter. The fungal OTU composition was largely structured by the swine house unit and season as well as by their interactions. Of the measured microclimate variables, relative humidity, particulate matters (PMs), ammonia, and stocking density were significantly correlated with fungal OTU composition. The variation in beta diversity was higher within swine houses during summer, which indicates that the airborne fungal community composition was more heterogeneous in summer compared to winter. We also identified several potential allergen/pathogen related fungal genera in swine houses. The total relative abundance of potential allergen/pathogen related fungal genera varied between swine houses in both seasons, and showed positive correlation with PM2.5. Overall, our findings show that the abundance, diversity and composition of airborne fungi are highly variable in swine houses and to a large extent structured by indoor microclimate variables of swine houses. PMID:27892507
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NASA Astrophysics Data System (ADS)
Kumari, Priyanka; Woo, Cheolwoon; Yamamoto, Naomichi; Choi, Hong-Lim
2016-11-01
We examined the abundance, diversity and community composition of airborne fungi in swine houses during winter and summer seasons by using quantitative PCR and Illumina HiSeq sequencing of ITS1 region. The abundance of airborne fungi varied significantly only between seasons, while fungal diversity varied significantly both within and between seasons, with both abundance and diversity peaked in winter. The fungal OTU composition was largely structured by the swine house unit and season as well as by their interactions. Of the measured microclimate variables, relative humidity, particulate matters (PMs), ammonia, and stocking density were significantly correlated with fungal OTU composition. The variation in beta diversity was higher within swine houses during summer, which indicates that the airborne fungal community composition was more heterogeneous in summer compared to winter. We also identified several potential allergen/pathogen related fungal genera in swine houses. The total relative abundance of potential allergen/pathogen related fungal genera varied between swine houses in both seasons, and showed positive correlation with PM2.5. Overall, our findings show that the abundance, diversity and composition of airborne fungi are highly variable in swine houses and to a large extent structured by indoor microclimate variables of swine houses.
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[The ecology of ticks, tick-borne diseases and biological tick control in Baden-Württemberg].
Sebastian, P; Mackenstedt, U; Wassermann, M; Wurst, E; Hartelt, K; Petney, T; Pfäffle, M; Littwin, N; Steidle, J L M; Selzer, P; Norra, S; Böhnke, D; Gebhardt, R; Kahl, O; Dautel, H; Oehme, R
2014-05-01
Ticks and tick-borne diseases are of great significance for the health of humans and animals. However, the factors influencing their distribution and dynamics are inadequately known. In a project financed by the Baden-Württemberg Ministry of the Environment, Climate and Energy Industry, as part of the program BWPLUS, interdisciplinary specialists work together to determine the influence of weather, (micro)climate, habitat, land use, human activities, and the population dynamics of host animals on the distribution and abundance of ticks and the diseases that they transmit in Baden-Württemberg. The project comprises four modules: the large-scale distribution of ticks in Baden-Württemberg (module 1), detailed studies of host-tick-pathogen interaction in relation to the microclimate (module 2), and the spatial occurrence of important tick-borne pathogens (module 3). The fourth module involves the comprehensive analysis and synthesis of all data in order to determine the relative importance of the factors studied and to develop a risk model. Recently, intensive investigations into tick control have been undertaken using various entomopathogenic fungi and nematodes as well as a parasitoid wasp. Our aim was to determine whether these natural enemies could be used to effectively reduce the number of free-living ticks.
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Root traits predict decomposition across a landscape-scale grazing experiment
Smith, Stuart W; Woodin, Sarah J; Pakeman, Robin J; Johnson, David; van der Wal, René
2014-01-01
Root litter is the dominant soil carbon and nutrient input in many ecosystems, yet few studies have considered how root decomposition is regulated at the landscape scale and how this is mediated by land-use management practices. Large herbivores can potentially influence below-ground decomposition through changes in soil microclimate (temperature and moisture) and changes in plant species composition (root traits). To investigate such herbivore-induced changes, we quantified annual root decomposition of upland grassland species in situ across a landscape-scale livestock grazing experiment, in a common-garden experiment and in laboratory microcosms evaluating the influence of key root traits on decomposition. Livestock grazing increased soil temperatures, but this did not affect root decomposition. Grazing had no effect on soil moisture, but wetter soils retarded root decomposition. Species-specific decomposition rates were similar across all grazing treatments, and species differences were maintained in the common-garden experiment, suggesting an overriding importance of litter type. Supporting this, in microcosms, roots with lower specific root area (m2 g−1) or those with higher phosphorus concentrations decomposed faster. Our results suggest that large herbivores alter below-ground carbon and nitrogen dynamics more through their effects on plant species composition and associated root traits than through effects on the soil microclimate. PMID:24841886
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Varner, Johanna; Lambert, Mallory S.; Horns, Joshua J.; Laverty, Sean; Dizney, Laurie; Beever, Erik; Dearing, M. Denise
2015-01-01
Wildfires are increasing in frequency and severity as a result of climate change in many ecosystems; however, effects of altered disturbance regimes on wildlife remain poorly quantified. Here, we leverage an unexpected opportunity to investigate how fire affects the occupancy and abundance of a climate-sensitive habitat specialist, the American pika (Ochotona princeps). We determine the effects of a fire on microclimates within talus and explore habitat factors promoting persistence and abundance in fire-affected habitat. During the fire, temperatures in talus interstices remained below 19°C, suggesting that animals could have survived in situ. Within 2 years, pikas were widely distributed throughout burned areas and did not appear to be physiologically stressed at severely burned sites. Furthermore, pika densities were better predicted by topographic variables known to affect this species than by metrics of fire severity. This widespread distribution may reflect quick vegetation recovery and the fact that the fire did not alter the talus microclimates in the following years. Together, these results highlight the value of talus as a thermal refuge for small animals during and after fire. They also underscore the importance of further study in individual species’ responses to typical and altered disturbance regimes.
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Ferrari, Virginia; Dellacassa, Eduardo; Coniberti, Andrés; Disegna, Edgardo
2017-02-01
Aspergillus spp. and Penicillium spp. are the main producers of ochratoxin A (OTA), a mycotoxin responsible for fatal human diseases. Some authorities have established a maximum of 2 μg/L of OTA in wine. Although the incidence and occurrence of OTA in grapes and wine is highly related to climate conditions, as has been extensively documented, there is no conclusive information on the effects of cultivation systems on the presence of OTA. This study focuses on determining the effect of the trellis system, planting density and cordon height on plant microclimate and thus on Aspergillus spp. contamination and OTA production in Tannat wines in Southern Uruguay. Two experiments were conducted during the 2010-2011 growing season: (1) a strip split plot design with five replicates and two cordon heights (CH) (0.5 m and 1.0 m above the soil) were compared in two planting densities (PD) (0.8 and 1.5 m between plants); (2) a randomised complete block design, vertical shoot positioning (VSP) versus Lyra trellis systems were evaluated. The results suggest that, even the macro- and micro-climate growing conditions play an important part in Aspergillus developing on grapes. Agronomical practices also have an undoubted impact on the risk and control of OTA accumulation in wine.
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Spatial models reveal the microclimatic buffering capacity of old-growth forests.
Frey, Sarah J K; Hadley, Adam S; Johnson, Sherri L; Schulze, Mark; Jones, Julia A; Betts, Matthew G
2016-04-01
Climate change is predicted to cause widespread declines in biodiversity, but these predictions are derived from coarse-resolution climate models applied at global scales. Such models lack the capacity to incorporate microclimate variability, which is critical to biodiversity microrefugia. In forested montane regions, microclimate is thought to be influenced by combined effects of elevation, microtopography, and vegetation, but their relative effects at fine spatial scales are poorly known. We used boosted regression trees to model the spatial distribution of fine-scale, under-canopy air temperatures in mountainous terrain. Spatial models predicted observed independent test data well (r = 0.87). As expected, elevation strongly predicted temperatures, but vegetation and microtopography also exerted critical effects. Old-growth vegetation characteristics, measured using LiDAR (light detection and ranging), appeared to have an insulating effect; maximum spring monthly temperatures decreased by 2.5°C across the observed gradient in old-growth structure. These cooling effects across a gradient in forest structure are of similar magnitude to 50-year forecasts of the Intergovernmental Panel on Climate Change and therefore have the potential to mitigate climate warming at local scales. Management strategies to conserve old-growth characteristics and to curb current rates of primary forest loss could maintain microrefugia, enhancing biodiversity persistence in mountainous systems under climate warming.
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Automated soil gas monitoring chamber
Edwards, Nelson T.; Riggs, Jeffery S.
2003-07-29
A chamber for trapping soil gases as they evolve from the soil without disturbance to the soil and to the natural microclimate within the chamber has been invented. The chamber opens between measurements and therefore does not alter the metabolic processes that influence soil gas efflux rates. A multiple chamber system provides for repetitive multi-point sampling, undisturbed metabolic soil processes between sampling, and an essentially airtight sampling chamber operating at ambient pressure.
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Management of natural resources through automatic cartographic inventory
NASA Technical Reports Server (NTRS)
Rey, P. (Principal Investigator); Gourinard, Y.; Cambou, F.
1972-01-01
The author has identified the following significant results. Return beam vidicon and multispectral band scanner imagery will be correlated with existing vegetation and geologic maps of southern France and northern Spain to develop correspondence codes between map units and space data. Microclimate data from six stations, spectral measurements from a few meters to 2 km using ERTS-type filter and spectrometers, and leaf reflectance measurements will be obtained to assist in correlation studies.
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Translations on USSR Science and Technology Biomedical Sciences, Number 11
1977-10-14
over the quality of combined feeds and the microclimate parameters, appropriate preparations of the production sectors, prevention of the " mastitis ...fact, still incomprehensible to us: We formed ah isolated farm out of young animals vaccinated when 5 months old. A year later, four cows aborted...had 27 unfavorable areas left, in which we hope to achieve recovery this year. The fact that up to 23 percent non-calving young cows are introduced
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2009-08-01
improved road access and overhead power. The site contains a WISS shelter, five (5) 40’ connex containers, UMTE pedestal, shelter, and a weather ...monitoring station (Figure 3- 1 ). 3.1.8.3 Camera I site consists of a roughly l acre site with semi-improved road access and overhead power. The site...characteristics such as microclimate , soil temperature, and moisture regimes. which in turn influence the type of vegetation that will be found there
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NASA Astrophysics Data System (ADS)
Tapete, D.; Fratini, F.; Mazzei, B.; Camaiti, M.; Cantisani, E.; Riminesi, C.; Manganelli Del Fà, R.; Cuzman, O.; Tiano, P.
2012-04-01
One of the deterioration processes affecting mural paintings and rock surfaces within manmade hypogea consists in the formation of calcium carbonate crystallizations, which can create thick coverage and incrustations, even in some cases speleothems. These chemical reactions necessarily require the availability of calcium sources, which can be also of anthropogenic origin (e.g., lime-based mortars). Microclimate parameters also represent environmental forcing factors, on which the morphology and the degree of crystallinity of the precipitated carbonates depend. Understanding past/recent dynamics of carbonate precipitation implies a deep knowledge of the relationships between the exposed surfaces and the microclimate conditions, the impacts of external factors (e.g., groundwater infiltration and percolation from the overlying soil) and how they change over time. This is particularly fundamental for the preservation of hypogean sites which have not comparison with other typologies of environment due to their uniqueness, such as the ancient catacombs carved underneath the suburbs of Rome (Italy), since the 2nd century AD. In this paper we present the multidisciplinary methodological approach designed for the instrumental monitoring of the microphysical environment of the Catacombs of Saints Mark, Marcellian and Damasus, in the framework of the co-operation between the Institute for the Conservation and Valorization of Cultural Heritage and Pontifical Commission for Sacred Archaeology, Vatican, on the project HYPOGEA. Temperature inside the catacomb and on the surfaces, air relative humidity and CO2 concentration are the main of the parameters continuously measured by means of data loggers installed within the cubicles. Contemporarily, standardized methods of photographic documentation and digital micro-photogrammetry are used for change detection analysis of the painted surfaces and ancient plasters, as well as of the test areas purposely realized by applying fresh
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Modeling behavioral thermoregulation in a climate change sentinel.
Moyer-Horner, Lucas; Mathewson, Paul D; Jones, Gavin M; Kearney, Michael R; Porter, Warren P
2015-12-01
When possible, many species will shift in elevation or latitude in response to rising temperatures. However, before such shifts occur, individuals will first tolerate environmental change and then modify their behavior to maintain heat balance. Behavioral thermoregulation allows animals a range of climatic tolerances and makes predicting geographic responses under future warming scenarios challenging. Because behavioral modification may reduce an individual's fecundity by, for example, limiting foraging time and thus caloric intake, we must consider the range of behavioral options available for thermoregulation to accurately predict climate change impacts on individual species. To date, few studies have identified mechanistic links between an organism's daily activities and the need to thermoregulate. We used a biophysical model, Niche Mapper, to mechanistically model microclimate conditions and thermoregulatory behavior for a temperature-sensitive mammal, the American pika (Ochotona princeps). Niche Mapper accurately simulated microclimate conditions, as well as empirical metabolic chamber data for a range of fur properties, animal sizes, and environmental parameters. Niche Mapper predicted pikas would be behaviorally constrained because of the need to thermoregulate during the hottest times of the day. We also showed that pikas at low elevations could receive energetic benefits by being smaller in size and maintaining summer pelage during longer stretches of the active season under a future warming scenario. We observed pika behavior for 288 h in Glacier National Park, Montana, and thermally characterized their rocky, montane environment. We found that pikas were most active when temperatures were cooler, and at sites characterized by high elevations and north-facing slopes. Pikas became significantly less active across a suite of behaviors in the field when temperatures surpassed 20°C, which supported a metabolic threshold predicted by Niche Mapper. In general
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NASA Astrophysics Data System (ADS)
Pospelova, I.
2017-11-01
The article suggests an original way of keeping heat load and its compensation for a microclimate system by proposing the “Smart Wall”. The construction consists of specially combined composite materials including phase-transition materials. The method for determination of the layer thickness is proposed for a certain accumulation time. Varying the thickness and composition of the layer it is possible to achieve a low amount of the thermal conductivity coefficient and to obtain various functional characteristics of fences.
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Sleeping distance in wild wolf packs
Knick, S.T.; Mech, L.D.
1980-01-01
Sleeping distances were observed among members of 13 wild wolf (Canis lupus) packs and 11 pairs in northeastern Minnesota to determine if the distances correlated with pack size and composition. The study utilized aerial radio-tracking and observation during winter. Pack size and number of adults per pack were inversely related to pack average sleeping distance and variability. No correlation between sleeping distance and microclimate was observed. Possible relationships between social bonding and our results are discussed.
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[The occupational aspect of sudden cardiac death in coal miners].
Cherkesov, V V; Kobets, G P; Kopytina, R A; Kamkov, V P; Fufaeva, I G; Danilik, V M; Sizonenko, L N; Tsygankov, V A
1993-09-01
By means of epidemiological, clinico-functional, experimental, pathomorphological, histological and mathematical-statistical methods the authors showed that hard physical work under conditions of heating microclimate promoted quick development and advance of coronary heart disease in deeply working coal miners. Negative dynamics of sudden coronary death (SCD) rate was established, its pathophysiological mechanisms were specified. SCD risk factors were singled out and arranged accordingly to their importance. SCD in miners was suggested to be considered as professionally conditioned state.
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[Achievements and prospects in railway transport hygiene].
Kaptsov, V A
1997-01-01
A unique Institute of Railway Hygiene was created 70 years ago in Russia, one of the major railway countries in the world. Since then the Institute's staffers have carried out huge work on improvement of railway workers' health, prevention of their exposure to noise, unfavorable microclimate, vibration and other occupational hazards. Significant contribution into the world occupational hygiene was made by such Institute's professionals as S.F. Kazansky, P.I. Nikitin, A.M. Volkov and others.
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Linking Tree Growth Response to Measured Microclimate - A Field Based Approach
NASA Astrophysics Data System (ADS)
Martin, J. T.; Hoylman, Z. H.; Looker, N. T.; Jencso, K. G.; Hu, J.
2015-12-01
The general relationship between climate and tree growth is a well established and important tenet shaping both paleo and future perspectives of forest ecosystem growth dynamics. Across much of the American west, water limits growth via physiological mechanisms that tie regional and local climatic conditions to forest productivity in a relatively predictable way, and these growth responses are clearly evident in tree ring records. However, within the annual cycle of a forest landscape, water availability varies across both time and space, and interacts with other potentially growth limiting factors such as temperature, light, and nutrients. In addition, tree growth responses may lag climate drivers and may vary in terms of where in a tree carbon is allocated. As such, determining when and where water actually limits forest growth in real time can be a significant challenge. Despite these challenges, we present data suggestive of real-time growth limitation driven by soil moisture supply and atmospheric water demand reflected in high frequency field measurements of stem radii and cell structure across ecological gradients. The experiment was conducted at the Lubrecht Experimental Forest in western Montana where, over two years, we observed intra-annual growth rates of four dominant conifer species: Douglas fir, Ponderosa Pine, Engelmann Spruce and Western Larch using point dendrometers and microcores. In all four species studied, compensatory use of stored water (inferred from stem water deficit) appears to exhibit a threshold relationship with a critical balance point between water supply and demand. The occurrence of this point in time coincided with a decrease in stem growth rates, and the while the timing varied up to one month across topographic and elevational gradients, the onset date of growth limitation was a reliable predictor of overall annual growth. Our findings support previous model-based observations of nonlinearity in the relationship between climate and annual ring formation, and suggest a rather immediate growth response to critical micro-meteorological conditions occurring at different times across the landscape by linking the timing and magnitude of tree growth responses to in situ measurements of environmental conditions.
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Enhancing soil begins with soil biology and a stable soil microclimate
USDA-ARS?s Scientific Manuscript database
Protection of the soil resource from erosion requires reducing the surface impact from raindrop energy and maintaining soil structure and stability to allow more efficient infiltration of water into the soil column. These two processes are linked with practices associated with enhancing and maintain...
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Developmental priming of stomatal sensitivity to abscisic acid by leaf microclimate.
Pantin, Florent; Renaud, Jeanne; Barbier, François; Vavasseur, Alain; Le Thiec, Didier; Rose, Christophe; Bariac, Thierry; Casson, Stuart; McLachlan, Deirdre H; Hetherington, Alistair M; Muller, Bertrand; Simonneau, Thierry
2013-09-23
Plant water loss and CO2 uptake are controlled by valve-like structures on the leaf surface known as stomata. Stomatal aperture is regulated by hormonal and environmental signals. We show here that stomatal sensitivity to the drought hormone abscisic acid (ABA) is acquired during leaf development by exposure to an increasingly dryer atmosphere in the rosette plant Arabidopsis. Young leaves, which develop in the center of the rosette, do not close in response to ABA. As the leaves increase in size, they are naturally exposed to increasingly dry air as a consequence of the spatial arrangement of the leaves, and this triggers the acquisition of ABA sensitivity. Interestingly, stomatal ABA sensitivity in young leaves is rapidly restored upon water stress. These findings shed new light on how plant architecture and stomatal physiology have coevolved to optimize carbon gain against water loss in stressing environments. Copyright © 2013 Elsevier Ltd. All rights reserved.
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Proposed Standard for a Microclimate Cooling System for Emergency Responder Operations
2012-02-17
shock, circuit damage, overheating, fire , or explosion. If applicable, MCS vendors shall provide a certificate of compliance, which specifically cites...2, each configuration includes underwear , a duty uniform, ballistic helmet, and, boots. Table A-2 CBP PPE Configurations Configuration Components
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Mapping Topoclimate and Microclimate in the Monarch Butterfly Biosphere Reserve, Mexico
NASA Astrophysics Data System (ADS)
Weiss, S. B.
2006-12-01
Overwintering monarch butterflies in Mexico select areas of the high elevation Oyamel fir -pine forest providing a canopy that protects them from extremes of cold, heat, sun, and wind. These exacting microclimatic conditions are found in relatively small areas of forest with appropriate topography and canopy cover. The major goal of this investigation is to map topoclimatic and microclimatic conditions within the Monarch Butterfly Biosphere Reserve by combining temperature monitoring (iButton Thermochrons), hemispherical canopy photography, multiple regression, and GIS modeling. Temperature measurements included base weather stations and arrays of Thermochrons (on the north-side of trees at 2m height) across local topographic and canopy cover gradients. Topoclimatic models of minimum temperatures included topographic position, slope, and elevation, and predicted that thermal belts on slopes and cold air drainage into canyons create local minimum temperature gradients of 2°C. Topoclimatic models of maximum temperatures models included elevation, topographic position, and relative solar exposure, with local gradients of 3°C. These models, which are independent of forest canopy structure, were then projected across the entire region. Forest canopy structure, including direct and diffuse solar radiation, was assessed with hemispherical photography at each Thermochron site. Canopy cover affected minimum temperatures primarily on the calmest, coldest nights. Maximum temperatures were predicted by direct radiation below the canopy. Fine- scale grids (25 m spacing) at three overwintering sites characterized effects of canopy gaps and edges on temperature and wind exposure. The effects of temperature variation were considered for lipid loss rates, ability to take flight, and freezing mortality. Lipid loss rates were estimated by measured hourly temperatures. Many of the closed canopy sites allowed for substantial lipid reserves at the end of the season (March 15), but increases in average temperature could effectively deplete lipids by that time. The large influence of canopy cover on daytime maximum temperatures demonstrates that forest thinning directly reduces habitat suitability. Monarchs' flight behavior under warmer conditions suggests that daytime temperatures drive the dynamics of monarch distribution within colonies. Thinning also decreases nighttime minimum temperatures, and increases wind exposure. These results create a basis for quantitative understanding of the combinations of topography and forest structure that provide high quality overwintering habitat.
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Zhao, Jie; Wan, Songze; Zhang, Chenlu; Liu, Zhanfeng; Zhou, Lixia; Fu, Shenglei
2014-01-01
Ecological interactions between aboveground and belowground biodiversity have received many attentions in the recent decades. Although soil biodiversity declined with the decrease of plant diversity, many previous studies found plant species identities were more important than plant diversity in controlling soil biodiversity. This study focused on the responses of soil biodiversity to the altering of plant functional groups, namely overstory and understory vegetations, rather than plant diversity gradient. We conducted an experiment by removing overstory and/or understory vegetation to compare their effects on soil microbial phospholipid fatty acid (PLFA) and nematode diversities in eucalyptus monocultures. Our results indicated that both overstory and understory vegetations could affect soil microbial PLFA and nematode diversities, which manifested as the decrease in Shannon-Wiener diversity index (H') and Pielou evenness index (J) and the increase in Simpson dominance index (λ) after vegetation removal. Soil microclimate change explained part of variance of soil biodiversity indices. Both overstory and understory vegetations positively correlated with soil microbial PLFA and nematode diversities. In addition, the alteration of soil biodiversity might be due to a mixing effect of bottom-up control and soil microclimate change after vegetation removal in the studied plantations. Given the studied ecosystem is common in humid subtropical and tropical region of the world, our findings might have great potential to extrapolate to large scales and could be conducive to ecosystem management and service.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Porter, W.P.
1985-08-01
We continue to put considerable effort into analysis of the dynamics of interactions between environmental and animal variance and its implications for growth and reproduction. We have completed the physiological experiments necessary for defining a complete mass and energy budget for two species of lizards, Uta stansburiana, and Sceloporus undulatus. We have completed the programming and are evaluating calculations for potential growth and reproduction for Sceloporus undulatus for the sandhill country of western Nebraska, where we have field data on microclimates, doubly labeled water measurements, and growth and reproduction measurements to do a thorough test of the microclimate and ectothermmore » models that together calculate potential growth and reproduction. The doubly labeled water analysis system is calibrated and running very well. We are just beginning analysis of the lizard samples from Nebraska. In deer mice, marmots and prairie dogs we have found significant diurnal and seasonal changes in body temperature and activity times. Deer mice in the field may exhibit 6-7 degree and as much as 20 degree body temperature changes in 15 to 20 minute intervals. Winter work in Jackson Hole at -40C showed capability for core temperature drops in deer mice of 8C in one minute and full recovery once the animal could burrow into the snow. Our calculations show that this variability saves significantly in energy costs.« less
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Novel Cooling Strategies for Military Training and Operations.
Lee, Jason K W; Kenefick, Robert W; Cheuvront, Samuel N
2015-11-01
The deleterious effects of environmental heat stress, combined with high metabolic loads and protective clothing and equipment of the modern Warfighter, impose severe heat strain, impair task performance, and increase risk of heat illness, thereby reducing the chance for mission success. Despite the implementation of heat-risk mitigation procedures over the past decades, task performance still suffers and exertional heat illness remains a major military problem. We review 3 novel heat mitigation strategies that may be implemented in the training or operational environment to reduce heat strain and the risk of exertional heat illness. These strategies include ingestion of ice slurry, arm immersion cooling, and microclimate cooling. Each of these strategies is suitable for use in different scenarios and the choice of cooling strategy is contingent on the requirements, circumstances, and constraints of the training and operational scenario. Ingestion of ice slurry and arm immersion cooling are practical strategies that may be implemented during training scenarios; ice slurry can be ingested before and during exercise, whereas arm immersion cooling can be administered after exercise-heat exposure. In the operational environment, existing microclimate cooling can be implemented with retrofitted vehicles and as an unmounted system, and it has the potential for use in many military occupational scenarios. This review will discuss the efficacy, limitations, and practical considerations for field implementation of each strategy.
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Rates of surficial rock creep on hillslopes in Western Colorado
Schumm, S.A.
1967-01-01
The average rate of downshope movement of rock fragments on shale hillslopes is directly proportional to the sine of the slope angle or that component of the gravitational force which acts parallel to the hillslope. The rates of surficial rock creep range from a few millimeters per year on a 3degree slope to almost 70 millimeters per year on a 40-degree slope, but these rates vary with natural variations in soil characteristics and microclimate, as well as with accidental disturbances.
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Concerning modeling of double-stage water evaporation cooling
NASA Astrophysics Data System (ADS)
Shatskiy, V. P.; Fedulova, L. I.; Gridneva, I. V.
2018-03-01
The matter of need for setting technical norms for production, as well as acceptable microclimate parameters, such as temperature and humidity, at the work place, remains urgent. Use of certain units should be economically sound and that should be taken into account for construction, assembly, operation, technological, and environmental requirements. Water evaporation coolers are simple to maintain, environmentally friendly, and quite cheap, but the development of the most efficient solutions requires mathematical modeling of the heat and mass transfer processes that take place in them.
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[Occupational hygiene at solar-energy electric power plants].
Lipkina, L I; Kolesnikova, A V; Tsirkova, N L
1991-01-01
The labour conditions of the personnel engaged in servicing an experimental solar electric power station in warm seasons of the year were characterized by the unfavourable environmental factors peculiar of working out-doors (heliostat sites) and in the station's shops (solar radiation, heating microclimate, noise). Combinations and activity of those factors were professionally determined. Established was the role of the labour conditions and respective occupational peculiarities in the individual response formation to work overload. A set of health-related preventive measures was also proposed.
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NASA Astrophysics Data System (ADS)
Katsoulas, N.; Antoniadis, D.; Tsirogiannis, I. L.; Labraki, E.; Bartzanas, T.; Kittas, C.
2017-05-01
The objectives of this effort was to study the effect of vertical (green wall) and horizontal (pergola) green structures on the microclimate conditions of the building surroundings and estimate the thermal perception and heat stress conditions near the two structures. The experimental data were used to validate the results simulated by the recent version (V4.0 preview III) of ENVI-met software which was used to simulate the effect of different design parameters of a pergola and a green façade on microclimate and heat stress conditions. Further aim is to use these results for better design of green structures. The microclimate measurements were carried out in real scale structures (hydroponic pergola and hydroponic green wall) at the Kostakii Campus of the Technological Education Institute of Epirus (Arta, Greece). The validation results showed a very good agreement between measured and simulated values of air temperature, with Tair,sim = 0.98 Tair,meas in the Empty atrium and Tair,sim = 0.99 Tair,meas in the Atrium with pergola, with a determination coefficient R 2 of 0.98 and 0.93, respectively. The model was used to predict the effects of green structures on air temperature (Tair), relative humidity (RH), and mean radiant temperature (Tmrt). The output values of these parameters were used as input data in the RayMan pro (V 2.1) model for estimating the physiologically equivalent temperature (PET) of different case scenarios. The average daytime value of simulated air temperature in the atrium for the case without and with pergola during three different days was 29.2 and 28.9 °C while the corresponding measured values were 29.7 and 29.2 °C. The results showed that compared to the case with no pergola in the atrium, covering 100% the atrium area with a planted pergola reduced at the hottest part of the day Tmrt and PET values by 29.4 and 17.9 °C, respectively. Although the values of air temperature (measured and simulated) were not greatly affected by the
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Predicting the Spatial Variability of Fuel Moisture Content in Mountainous Eucalyptus Forests
NASA Astrophysics Data System (ADS)
Sheridan, G. J.; Nyman, P.; Lane, P. N. J.; Metzen, D.
2014-12-01
In steep mountainous landscapes, topographic aspect can play a significant role in small-scale (ie. scales in the order of 10's ha) variability in surface fuel moisture. Experimental sites for monitoring microclimate variables and moisture content in litter and in near-surface soils were established at a control site and on four contrasting aspects (north, south, east and west) in southeast Australia. At each of the four microclimate sites sensors are arranged to measure the soil moisture (2 replicates), surface fuel moisture at 2.5cm depth (12 replicates), precipitation throughfall (3 replicates), radiation (3 replicates), and screen level relative humidity, air temperature, leaf wetness, and wind speed (1 replicate of each). Temperature and relative humidity are also measured within the dead fine surface fuel using Ibutton's (4 replicates). All measurements are logged continuously at 15 min intervals. The moisture content of the surface fuel is estimated using a novel method involving high-replication of low-cost continuous soil moisture sensors placed at the centre of a 5cm deep sample of fine dead surface fuel, referred to here as "litter-packs". The litter-packs were constructed from fuels collected from the area surrounding the microclimate site. The initial results show the moisture regime on the forest floor was highly sensitive to the incoming shortwave radiation, which was up to 6 times higher in the north-facing (equatorial) slopes due to slope orientation and the sparse vegetation compared to vegetation on the south-facing (polar facing) slopes. Differences in shortwave radiation resulted in peak temperatures within the litter that were up to 2 times higher on the equatorial-facing site than those on the polar-facing site. For instance, on a day in November 2013 with maximum open air temperature of 35o C, the temperatures within the litter layer at the north-facing and south-facing sites were 54o C and 32o C, respectively, despite air temperature at the
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Non-structural origins of asymmetric topography in semi-arid environments
NASA Astrophysics Data System (ADS)
Richardson, P. W.; Perron, T.; Miller, S. R.
2012-12-01
Geoscientists have long noted that landscapes in some regions have pole-facing slopes that are steeper than equator-facing slopes. In some cases, the asymmetry has a simple structural cause, such as slopes that form parallel to bedrock strata, but in others, the absence of obvious structural controls and the consistent pole-equator orientation of the asymmetry suggest that different microclimates on opposing slopes may be the cause. Compelling as the microclimatic correlation may be, it has not been demonstrated how microclimatic effects can influence long-term landscape evolution sufficiently to generate asymmetric topography. Two conflicting hypotheses that depend on microclimates have been proposed. In one hypothesis, a microclimate-induced contrast in the efficiency of erosion processes, such as channel incision, creates a difference in erosion rates on opposing slopes that drives drainage divide migration until the slope asymmetry compensates for the difference in erosional efficiency. In the other, more popular hypothesis, the asymmetric erosional efficiency is not a sufficient condition. Instead, faster sediment aggradation at the foot of more efficiently eroding slopes forces axial streams to undercut the opposing slopes, eventually creating an asymmetry in steepness. We seek to determine whether undercutting is a necessary mechanism, and focus our efforts on understanding the mechanisms responsible for the topographic asymmetry at Gabilan Mesa, CA, a landscape with a high degree of asymmetry and a simple underlying lithology. We investigate the long-term topographic consequences of these mechanisms with a landscape evolution model. In the first set of model experiments, we explore the effects of aspect-dependent differences in the efficiency of soil creep, the magnitude of a channel incision threshold, and runoff production. The second model experiment includes undercutting of slopes in response to lateral base level migration. We examined which mechanism
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2013-01-01
This study was designed to investigate the relationship between the microclimate temperature and clothing insulation (Icl) under comfortable environmental conditions. In total, 20 subjects (13 women, 7 men) took part in this study. Four environmental temperatures were chosen: 14°C (to represent March/April), 25°C (May/June), 29°C (July/August), and 23°C (September/October). Wind speed (0.14ms-1) and humidity (45%) were held constant. Clothing microclimate temperatures were measured at the chest (Tchest) and on the interscapular region (Tscapular). Clothing temperature of the innermost layer (Tinnermost) was measured on this layer 30 mm above the centre of the left breast. Subjects were free to choose the clothing that offered them thermal comfort under each environmental condition. We found the following results. 1) All clothing factors except the number of lower clothing layers (Llower), showed differences between the different environmental conditions (P<0.05). The ranges of Tchest were 31.6 to 33.5°C and 32.2 to 33.4°C in Tscapular. The range of Tinnermost was 28.6 to 32.0°C. The range of the upper clothing layers (Lupper) and total clothing mass (Mtotal) was 1.1 to 3.2 layers and 473 to 1659 g respectively. The range of Icl was 0.78 to 2.10 clo. 2) Post hoc analyses showed that analysis of Tinnermost produced the same results as for that of Icl. Likewise, the analysis of Lupper produced the same result as the analysis of the number of total layers (Ltotal) within an outfit. 3) Air temperature (ta) had positive relationships with Tchest and Tscapular and with Tinnermost but had inverse correlations with Icl, Mtotal, Lupper and Ltotal. Tchest, Tscapular, and Tinnermost increased as ta rose. 4) Icl had inverse relationships with Tchest and Tinnermost, but positive relationships with Mtotal, Lupper and Ltotal. Icl could be estimated by Mtotal, Lupper, and Tscapular using a multivariate linear regression model. 5) Lupper had positive relationships with Icl
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Forest productivity varies with soil moisture more than temperature in a small montane watershed
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wei, Liang; Zhou, Hang; Link, Timothy E
Mountainous terrain creates variability in microclimate, including nocturnal cold air drainage and resultant temperature inversions. Driven by the elevational temperature gradient, vapor pressure deficit (VPD) also varies with elevation. Soil depth and moisture availability often increase from ridgetop to valley bottom. These variations complicate predictions of forest productivity and other biological responses. We analyzed spatiotemporal air temperature (T) and VPD variations in a forested, 27-km 2 catchment that varied from 1000 to 1650 m in elevation. Temperature inversions occurred on 76% of mornings in the growing season. The inversion had a clear upper boundary at midslope (~1370 m a.s.l.). Vapormore » pressure was relatively constant across elevations, therefore VPD was mainly controlled by T in the watershed. Here, we assessed the impact of microclimate and soil moisture on tree height, forest productivity, and carbon stable isotopes (δ 13C) using a physiological forest growth model (3-PG). Simulated productivity and tree height were tested against observations derived from lidar data. The effects on photosynthetic gas-exchange of dramatic elevational variations in T and VPD largely cancelled as higher temperature (increasing productivity) accompanies higher VPD (reducing productivity). Although it was not measured, the simulations suggested that realistic elevational variations in soil moisture predicted the observed decline in productivity with elevation. Therefore, in this watershed, the model parameterization should have emphasized soil moisture rather than precise descriptions of temperature inversions.« less
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NASA Astrophysics Data System (ADS)
Broadbent, Ashley M.; Coutts, Andrew M.; Tapper, Nigel J.; Demuzere, Matthias; Beringer, Jason
2017-09-01
Prolonged drought has threatened traditional potable urban water supplies in Australian cities, reducing capability to adapt to climate change and mitigate against extreme. Integrated urban water management (IUWM) approaches, such as water sensitive urban design (WSUD), reduce the reliance on centralised potable water supply systems and provide a means for retaining water in the urban environment through stormwater harvesting and reuse. This study examines the potential for WSUD to provide cooling benefits and reduce human exposure and heat stress and thermal discomfort. A high-resolution observational field campaign, measuring surface level microclimate variables and remotely sensed land surface characteristics, was conducted in a mixed residential suburb containing WSUD in Adelaide, South Australia. Clear evidence was found that WSUD features and irrigation can reduce surface temperature (T s) and air temperature (T a) and improve human thermal comfort (HTC) in urban environments. The average 3 pm T a near water bodies was found to be up to 1.8 °C cooler than the domain maximum. Cooling was broadly observed in the area 50 m downwind of lakes and wetlands. Design and placement of water bodies were found to affect their cooling effectiveness. HTC was improved by proximity to WSUD features, but shading and ventilation were also effective at improving thermal comfort. This study demonstrates that WSUD can be used to cool urban microclimates, while simultaneously achieving other environmental benefits, such as improved stream ecology and flood mitigation.
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NASA Astrophysics Data System (ADS)
Gomez, A. M.; McDonald, K. C.; Shein, K. A.; Devries, S. L.; Armstrong, R.; Carlo, M.
2017-12-01
The third global coral bleaching event, which began in mid-2014, is a major environmental stressor that has been causing significant documented damage to coral reefs in all tropical ocean basins. This worldwide phenomenon is the longest and largest coral bleaching event on record and now finally appears to be ending. During this event, some coral colonies proved to be more resilient to increased ocean temperatures while others bleached severely. This research investigates the spatial and temporal variability of bleaching stress on coral reefs in La Parguera, Puerto Rico, and Southeastern Florida to help further understand the role of temperature and light in coral bleaching. We examine the microclimate within two coral reef systems, using in situ collections of temperature and light data from data loggers deployed throughout Cayo Enrique and Cayo Mario in La Parguera, and Lauderdale-By-The-Sea in FLorida. The in situ measurements are compared to NOAA Coral Reef Watch's 5-km sea surface temperature data as well as to the associated Light Stress Damage Product. Research outcomes include statistical analyses of in situ measurements with satellite datasets supporting enhanced interpretation of satellite-based SST and light products, and ecological niche modeling to assess where corals could potentially survive under future climate conditions. Additional understanding of the microclimate encompassing coral reefs and improved satellite SST and light data will ultimately help coral reef ecosystem managers and policy makers in prioritizing resources toward the monitoring and protection of coral reef ecosystems.
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Matheny, Ashley M.; Bohrer, Gil; Vogel, Christoph S.; ...
2014-12-04
Intermediate disturbances shape forest structure and composition, which may in turn alter carbon, nitrogen, and water cycling. We used a large-scale experiment in a forest in northern lower Michigan where we prescribed an intermediate disturbance by stem girdling all canopy-dominant early successional trees to simulate an accelerated age-related senescence associated with natural succession.Using 3 years of eddy covariance and sap flux measurements in the disturbed area and an adjacent control plot, we analyzed disturbance-induced changes to plot level and species-specific transpiration and stomatal conductance. We found transpiration to be ~15% lower in disturbed plots than in unmanipulated control plots. However,more » species-specific responses to changes in microclimate varied. While red oak and white pine showed increases in stomatal conductance during post disturbance (62.5 and 132.2%, respectively), redmaple reduced stomatal conductance by 36.8%. We used the hysteresis between sap flux and vapor pressure deficit to quantify diurnal hydraulic stress incurred by each species in both plots. Red oak, a ring porousanisohydric species, demonstrated the largest mean relative hysteresis, while red maple, bigtooth aspen, andpaper birch, all diffuse porous species, had the lowest relative hysteresis. We employed the Penman-Monteithmodel for LE to demonstrate that these species-specific responses to disturbance are not well captured using current modeling strategies and that accounting for changes to leaf area index and plot microclimate are insufffcient to fully describe the effects of disturbance on transpiration.« less
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Host tree phenology affects vascular epiphytes at the physiological, demographic and community level
Einzmann, Helena J. R.; Beyschlag, Joachim; Hofhansl, Florian; Wanek, Wolfgang; Zotz, Gerhard
2015-01-01
The processes that govern diverse tropical plant communities have rarely been studied in life forms other than trees. Structurally dependent vascular epiphytes, a major part of tropical biodiversity, grow in a three-dimensional matrix defined by their hosts, but trees differ in their architecture, bark structure/chemistry and leaf phenology. We hypothesized that the resulting seasonal differences in microclimatic conditions in evergreen vs. deciduous trees would affect epiphytes at different levels, from organ physiology to community structure. We studied the influence of tree leaf phenology on vascular epiphytes on the Island of Barro Colorado, Panama. Five tree species were selected, which were deciduous, semi-deciduous or evergreen. The crowns of drought-deciduous trees, characterized by sunnier and drier microclimates, hosted fewer individuals and less diverse epiphyte assemblages. Differences were also observed at a functional level, e.g. epiphyte assemblages in deciduous trees had larger proportions of Crassulacean acid metabolism species and individuals. At the population level a drier microclimate was associated with lower individual growth and survival in a xerophytic fern. Some species also showed, as expected, lower specific leaf area and higher δ13C values when growing in deciduous trees compared with evergreen trees. As hypothesized, host tree leaf phenology influences vascular epiphytes at different levels. Our results suggest a cascading effect of tree composition and associated differences in tree phenology on the diversity and functioning of epiphyte communities in tropical lowland forests. PMID:25392188
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Waudby, Helen P; Petit, Sophie
2017-05-01
Deserts exhibit extreme climatic conditions. Small desert-dwelling vertebrates have physiological and behavioral adaptations to cope with these conditions, including the ability to seek shelter. We investigated the temperature (T) and relative humidity (RH) regulating properties of the soil cracks that characterize the extensive cracking-clay landscapes of arid Australia, and the extent of their use by 2 small marsupial species: fat-tailed and stripe-faced dunnarts (Sminthopsis crassicaudata and Sminthopsis macroura). We measured hourly (over 24-h periods) the T and RH of randomly-selected soil cracks compared to outside conditions, during 2 summers and 2 winters. We tracked 17 dunnarts (8 Sminthopsis crassicaudata and 9 Sminthopsis macroura) to quantify their use of cracks. Cracks consistently moderated microclimate, providing more stable conditions than available from non-crack points, which often displayed comparatively dramatic fluctuations in T and RH. Both dunnart species used crack shelters extensively. Cracks constitute important shelter for small animals during extreme conditions by providing a stable microclimate, which is typically cooler than outside conditions in summer and warmer in winter. Cracks likely play a fundamental sheltering role by sustaining the physiological needs of small mammal populations. Globally, cracking-clay areas are dominated by agricultural land uses, including livestock grazing. Management of these systems should focus not only on vegetation condition, but also on soil integrity, to maintain shelter resources for ground-dwelling fauna. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.
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Environmental monitoring in four European museums
NASA Astrophysics Data System (ADS)
Camuffo, Dario; Van Grieken, Rene; Busse, Hans-Jürgen; Sturaro, Giovanni; Valentino, Antonio; Bernardi, Adriana; Blades, Nigel; Shooter, David; Gysels, Kristin; Deutsch, Felix; Wieser, Monika; Kim, Oliver; Ulrych, Ursula
In a European multidisciplinary research project concerning environmental diagnostics, museums have been selected, having different climate and pollution conditions, i.e.: Correr Museum, Venice (Italy); Kunsthistorisches Museum, Vienna (Austria); Royal Museum of Fine Arts, Antwerp (Belgium); Sainsbury Centre for Visual Arts, Norwich (UK). Some field tests investigated the microclimate, the gaseous and particulate air pollution and the biological contamination to suggest mitigative techniques that may reduce the potential for damage in the long run. Potential risk factors are generated by imbalance in temperature and humidity, generated by heating, air conditioning or ventilating system (HVAC), or the building structures, exchange of outside air, or large visitor numbers. HVAC may also enhance indoor gaseous pollution. Plants and carpets represent potential niches for bacterial colonisation. Pollutants and particles have been recognised having partly external and partly internal origin. Tourism has a direct negative impact, i.e. transport of external particles, release of heat, vapour and CO 2, as well as generation of turbulence, which increases the deposition rate of particulate matter. However, the main problem is that the microclimate has been planned for the well being of visitors during only the visiting time, disregarding the needs of conservation that requires a constant climate by day and by night. In some of these cases, better environmental niches have been obtained with the help of showcases. In other cases, showcases worsened the situation, especially when incandescent lamps were put inside.
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Entling, Martin H.; Mantilla-Contreras, Jasmin
2017-01-01
Microclimate in different positions on a host plant has strong direct effects on herbivores. But little is known about indirect effects due to changes of leaf traits. We hypothesized that herbivory increases from upper canopy to lower canopy and understory due to a combination of direct and indirect pathways. Furthermore, we hypothesized that herbivory in the understory differs between tree species in accordance with their leaf traits. We investigated herbivory by leaf chewing insects along the vertical gradient of mixed deciduous forest stands on the broad-leaved tree species Fagus sylvatica L. (European beech) with study sites located along a 140 km long transect. Additionally, we studied juvenile Acer pseudoplatanus L. (sycamore maple) and Carpinus betulus L. (hornbeam) individuals within the understory as a reference of leaf traits in the same microclimate. Lowest levels of herbivory were observed in upper canopies, where temperatures were highest. Temperature was the best predictor for insect herbivory across forest layers in our study. However, the direction was opposite to the generally known positive relationship. Herbivory also varied between the three tree species with lowest levels for F. sylvatica. Leaf carbon content was highest for F. sylvatica and probably indicates higher amounts of phenolic defense compounds. We conclude that the effect of temperature must have been indirect, whereby the expected higher herbivory was suppressed due to unfavorable leaf traits (lower nitrogen content, higher toughness and carbon content) of upper canopy leaves compared to the understory. PMID:28099483
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2017-01-01
Neighboring plants can decrease or increase each other’s likelihood of damage from herbivores through associational resistance or susceptibility, respectively. Associational effects (AE) can transpire through changes in herbivore or plant traits that affect herbivore movement, densities, and feeding behaviors to ultimately affect plant damage. While much work has focused on understanding the mechanisms that underlie associational effects, we know little about how these mechanisms are influenced by neighborhood composition, i.e., plant density or relative frequency which is necessary to make predictions about when AE should occur in nature. Using a series of field and greenhouse experiments, I examined how plant density and relative frequency affected plant damage to Solanum carolinense and four mechanisms that underlie AE; (i) accumulation of insect herbivores and arthropod predators, (ii) microclimate conditions, (iii) plant resistance, and (iv) specialist herbivore preference. I found a positive relationship between S. carolinense damage and the relative frequency of a non-focal neighbor (Solidago altissima) and all four AE mechanisms were influenced by one or multiple neighborhood components. Frequency-dependence in S. carolinense damage is most likely due to greater generalist herbivore load on S. carolinense (through spillover from S. altissima) with microclimate variables, herbivore preference, predation pressures, and plant resistance having relatively weaker effects. Associational effects may have long-term consequences for these two plant species during plant succession and understanding context-dependent herbivory has insect pest management implication for other plant species in agriculture and forestry. PMID:28486538
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Forest productivity varies with soil moisture more than temperature in a small montane watershed
Wei, Liang; Zhou, Hang; Link, Timothy E; ...
2018-05-16
Mountainous terrain creates variability in microclimate, including nocturnal cold air drainage and resultant temperature inversions. Driven by the elevational temperature gradient, vapor pressure deficit (VPD) also varies with elevation. Soil depth and moisture availability often increase from ridgetop to valley bottom. These variations complicate predictions of forest productivity and other biological responses. We analyzed spatiotemporal air temperature (T) and VPD variations in a forested, 27-km 2 catchment that varied from 1000 to 1650 m in elevation. Temperature inversions occurred on 76% of mornings in the growing season. The inversion had a clear upper boundary at midslope (~1370 m a.s.l.). Vapormore » pressure was relatively constant across elevations, therefore VPD was mainly controlled by T in the watershed. Here, we assessed the impact of microclimate and soil moisture on tree height, forest productivity, and carbon stable isotopes (δ 13C) using a physiological forest growth model (3-PG). Simulated productivity and tree height were tested against observations derived from lidar data. The effects on photosynthetic gas-exchange of dramatic elevational variations in T and VPD largely cancelled as higher temperature (increasing productivity) accompanies higher VPD (reducing productivity). Although it was not measured, the simulations suggested that realistic elevational variations in soil moisture predicted the observed decline in productivity with elevation. Therefore, in this watershed, the model parameterization should have emphasized soil moisture rather than precise descriptions of temperature inversions.« less
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A dynamic tester to evaluate the thermal and moisture behaviour of the surface of textiles.
Li, Wenbin; Xu, Weilin; Wang, Hao; Wang, Xin
2016-01-01
The thermal and moisture behaviour of the microclimate of textiles is crucial in determining the physiological comfort of apparel, but it has not been investigated sufficiently due to the lack of particular evaluation techniques. Based on sensing, temperature controlling and wireless communicating technology, a specially designed tester has been developed in this study to evaluate the thermal and moisture behaviour of the surface of textiles in moving status. A temperature acquisition system and a temperature controllable hotplate have been established to test temperature and simulate the heat of human body, respectively. Relative humidity of the surface of fabric in the dynamic process has been successfully tested through sensing. Meanwhile, wireless communication technology was applied to transport the acquired data of temperature and humidity to computer for further processing. Continuous power supply was achieved by intensive contact between an elastic copper plate and copper ring on the rotating shaft. This tester provides the platform to evaluate the thermal and moisture behaviour of textiles. It enables users to conduct a dynamic analysis on the temperature and humidity together with the thermal and moisture transport behaviour of the surface of fabric in moving condition. Development of this tester opens the door of investigation on the micro-climate of textiles in real time service, and eventually benefits the understanding of the sensation comfort and wellbeing of apparel wearers. Copyright © 2015 Elsevier Ltd. All rights reserved.
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Contrasting growth responses of dominant peatland plants to warming and vegetation composition.
Walker, Tom N; Ward, Susan E; Ostle, Nicholas J; Bardgett, Richard D
2015-05-01
There is growing recognition that changes in vegetation composition can strongly influence peatland carbon cycling, with potential feedbacks to future climate. Nevertheless, despite accelerated climate and vegetation change in this ecosystem, the growth responses of peatland plant species to combined warming and vegetation change are unknown. Here, we used a field warming and vegetation removal experiment to test the hypothesis that dominant species from the three plant functional types present (dwarf-shrubs: Calluna vulgaris; graminoids: Eriophorum vaginatum; bryophytes: Sphagnum capillifolium) contrast in their growth responses to warming and the presence or absence of other plant functional types. Warming was accomplished using open top chambers, which raised air temperature by approximately 0.35 °C, and we measured air and soil microclimate as potential mechanisms through which both experimental factors could influence growth. We found that only Calluna growth increased with experimental warming (by 20%), whereas the presence of dwarf-shrubs and bryophytes increased growth of Sphagnum (46%) and Eriophorum (20%), respectively. Sphagnum growth was also negatively related to soil temperature, which was lower when dwarf-shrubs were present. Dwarf-shrubs may therefore promote Sphagnum growth by cooling the peat surface. Conversely, the effect of bryophyte presence on Eriophorum growth was not related to any change in microclimate, suggesting other factors play a role. In conclusion, our findings reveal contrasting abiotic and biotic controls over dominant peatland plant growth, suggesting that community composition and carbon cycling could be modified by simultaneous climate and vegetation change.
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Species-specific transpiration responses to intermediate disturbance in a northern hardwood forest
NASA Astrophysics Data System (ADS)
Matheny, Ashley M.; Bohrer, Gil; Vogel, Christoph S.; Morin, Timothy H.; He, Lingli; Frasson, Renato Prata de Moraes; Mirfenderesgi, Golnazalsadat; Schäfer, Karina V. R.; Gough, Christopher M.; Ivanov, Valeriy Y.; Curtis, Peter S.
2014-12-01
Intermediate disturbances shape forest structure and composition, which may in turn alter carbon, nitrogen, and water cycling. We used a large-scale experiment in a forest in northern lower Michigan where we prescribed an intermediate disturbance by stem girdling all canopy-dominant early successional trees to simulate an accelerated age-related senescence associated with natural succession. Using 3 years of eddy covariance and sap flux measurements in the disturbed area and an adjacent control plot, we analyzed disturbance-induced changes to plot level and species-specific transpiration and stomatal conductance. We found transpiration to be 15% lower in disturbed plots than in unmanipulated control plots. However, species-specific responses to changes in microclimate varied. While red oak and white pine showed increases in stomatal conductance during postdisturbance (62.5 and 132.2%, respectively), red maple reduced stomatal conductance by 36.8%. We used the hysteresis between sap flux and vapor pressure deficit to quantify diurnal hydraulic stress incurred by each species in both plots. Red oak, a ring porous anisohydric species, demonstrated the largest mean relative hysteresis, while red maple, bigtooth aspen, and paper birch, all diffuse porous species, had the lowest relative hysteresis. We employed the Penman-Monteith model for LE to demonstrate that these species-specific responses to disturbance are not well captured using current modeling strategies and that accounting for changes to leaf area index and plot microclimate are insufficient to fully describe the effects of disturbance on transpiration.
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Multiple climate drivers accelerate Arctic plant community senescence
NASA Astrophysics Data System (ADS)
Livensperger, C.; Steltzer, H.; Wallenstein, M. D.; Weintraub, M. N.
2015-12-01
Alteration of seasonal phenology cues due to climate change has led to changes in the onset and duration of the growing season. While photoperiod often acts as an ultimate control on phenological events, recent studies have shown that environmental cues such as temperature and soil water content can modify the direction and rate of senescence processes. Warmer temperatures have resulted in an observed trend towards delayed senescence across temperate latitudes. However, Arctic regions are characterized by extreme seasonality and rapidly decreasing photoperiod, and consequently senescence may not shift as climate warms. We monitored the timing of Arctic plant community senescence for three years under the framework of an experimental manipulation that altered seasonal phenological cues through warming and earlier snowmelt. Alternative models of senescence were tested to determine if microclimate (air temperature, soil temperature, and soil moisture) or start of season phenology affect the timing and rate of community senescence. We found that all three microclimate predictors contributed to explaining variation in timing of senescence, suggesting that photoperiod is not the sole control on timing of senescence in Arctic plant communities. Rather, increased air and soil temperatures along with drier soil conditions, led to acceleration in the onset of senescence at a community level. Our data suggest that (1) multiple climate drivers predict timing of plant community senescence, and (2) climate change could result in a shorter peak season due to earlier onset of senescence, which would decrease the potential carbon uptake in moist acidic tundra.
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Multilocus adaptation associated with heat resistance in reef-building corals.
Bay, Rachael A; Palumbi, Stephen R
2014-12-15
The evolution of tolerance to future climate change depends on the standing stock of genetic variation for resistance to climate-related impacts, but genes contributing to climate tolerance in wild populations are poorly described in number and effect. Physiology and gene expression patterns have shown that corals living in naturally high-temperature microclimates are more resistant to bleaching because of both acclimation and fixed effects, including adaptation. To search for potential genetic correlates of these fixed effects, we genotyped 15,399 single nucleotide polymorphisms (SNPs) in 23 individual tabletop corals, Acropora hyacinthus, within a natural temperature mosaic in backreef lagoons on Ofu Island, American Samoa. Despite overall lack of population substructure, we identified 114 highly divergent SNPs as candidates for environmental selection, via multiple stringent outlier tests, and correlations with temperature. Corals from the warmest reef location had higher minor allele frequencies across these candidate SNPs, a pattern not seen for noncandidate loci. Furthermore, within backreef pools, colonies in the warmest microclimates had a higher number and frequency of alternative alleles at candidate loci. These data suggest mild selection for alternate alleles at many loci in these corals during high heat episodes and possible maintenance of extensive polymorphism through multilocus balancing selection in a heterogeneous environment. In this case, a natural population harbors a reservoir of alleles preadapted to high temperatures, suggesting potential for future evolutionary response to climate change. Copyright © 2014 Elsevier Ltd. All rights reserved.
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2009-10-01
and ratings of thermal comfort (TC) were measured at regular intervals. 3.0 RESULTS In study one, all IR1-4 paradigms significantly reduced... Thermal comfort and sensation in men wearing a cooling system controlled by skin temperatrure. Human Factors 49: 1033-1044, 2007. [7] Xu X
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SIMULATION OF A BIOFEEDBACK MICROCLIMATE COOLING SYSTEM USING A HUMAN THERMOREGULATION MODEL
2017-02-01
garment (LCG) The rate of LCG heat removal from the human body depends on coolant inlet temperature (Tin), clothing insulation worn over the LCG, flow...The efficiency η is equal to one when the outer clothing has sufficient insulation and the heat exchange between LCG and the external environment...0.27 m2·ºC·W-1 (1.73 clo). Insulation of protective ensembles prevent the LCG from absorbing heat from the environment (circulating liquid temperature
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Foley, Bryan J; Drozd, Ashley M; Bollard, Mary T; Laspina, Denise; Podobedov, Nikita; Zeniou, Nicholas; Rao, Anjali S; Andi, Babak; Jackimowicz, Rick; Sweet, Robert M; McSweeney, Sean; Soares, Alexei S
2016-02-01
A method is described for using custom snap-on lids to protect chemicals in microtiter plates from evaporation and contamination. The lids contain apertures (diameter 1.5, 1.0, or 0.5 mm) through which the chemical building blocks can be transferred. The lid with 0.5 mm apertures was tested using a noncontact acoustic liquid handler; the 1.0 and 1.5 mm lids were tested using two tip-based liquid handlers. All of the lids reduced the rate at which solvents evaporated to room air, and greatly reduced the rate of contamination by water and oxygen from room air. In steady-state measurements, the lids reduced the rate of evaporation of methanol, 1-hexene, and water by 33% to 248%. In cycled experiments, the contamination of aqueous solvent with oxygen was reduced below detectability and the rate at which DMSO engorged atmospheric water was reduced by 81%. Our results demonstrate that the lids preserve the integrity of air-sensitive reagents during the time needed for different types of liquid handlers to perform dispensations. Controlling degradation and evaporation of chemical building blocks exposed to the atmosphere is increasingly useful as the reagent volume is reduced by advances in liquid handling technology, such as acoustic droplet ejection. © 2015 Society for Laboratory Automation and Screening.
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Teixeira, Daniel C; Lacerda, Luiz D; Silva-Filho, Emmanoel V
2017-02-01
Mercury (Hg) concentrations in tropical forest soils and litter are up to 10 times higher than those from temperate and boreal forests. The majority of Hg that has been stored in tropical soils, as the forest is left intact, could be trapped in deeper layers of soil and only small quantities are exported to water bodies. The quantitative approach to the Hg cycle in tropical forests is uncommon; the South America Atlantic Forest indeed is a hotspot for species conservation and also seems to be for the Hg's cycle. This study reports on a biannual dynamics of Hg through different species assemblage of different successional stages in this biome, based on 24 litter traps used to collect litterfall from 3 different successional stages under a rainforest located at Brazilian Southeast. The mean Hg litterfall flux obtained was 6.1 ± 0.15 μg ha -1 yr -1 , while the mean Hg concentration in litter was 57 ± 16 ng g -1 and the accumulation of Hg via litterfall flux was 34.6 ± 1.2 μg m -2 yr -1 . These inventories are close to those found for tropical areas in the Amazon, but they were lower than those assessed for Atlantic Forest biome studies. These low concentrations are related to the remoteness of the area from pollution sources and probably to the climatic limitation, due to the altitude effects over the forest's eco-physiology. The mercury fluxes found in each different successional stage, correlated with time variations of global radiation, suggesting a mandatory role of the forest primary production over Hg deposition to the soil. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Observations of the microclimate of a lake under cold air advective conditions
NASA Technical Reports Server (NTRS)
Bill, R. G., Jr.; Sutherland, R. A.; Bartholic, J. F.
1977-01-01
The moderating effects of Lake Apopka, Florida, on downwind surface temperatures were evaluated under cold air advective conditions. Point temperature measurements north and south of the lake and data obtained from the NOAA satellite and a thermal scanner flown at 1.6 km, indicate that, under conditions of moderate winds (approximately 4m/sec), surface temperatures directly downwind may be higher than surrounding surface temperatures by as much as 5 C. With surface wind speed less than 1m/sec, no substantial temperature effects were observed. Results of this study are being used in land use planning, lake level control and in agriculture for selecting planting sites.
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Modeling Urban Energy Savings Scenarios Using Earth System Microclimate and Urban Morphology
NASA Astrophysics Data System (ADS)
Allen, M. R.; Rose, A.; New, J. R.; Yuan, J.; Omitaomu, O.; Sylvester, L.; Branstetter, M. L.; Carvalhaes, T. M.; Seals, M.; Berres, A.
2017-12-01
We analyze and quantify the relationships among climatic conditions, urban morphology, population, land cover, and energy use so that these relationships can be used to inform energy-efficient urban development and planning. We integrate different approaches across three research areas: earth system modeling; impacts, adaptation and vulnerability; and urban planning in order to address three major gaps in the existing capability in these areas: i) neighborhood resolution modeling and simulation of urban micrometeorological processes and their effect on and from regional climate; ii) projections for future energy use under urbanization and climate change scenarios identifying best strategies for urban morphological development and energy savings; iii) analysis and visualization tools to help planners optimally use these projections.
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Microclimate Evaluation of the Hradec Králové City using HUMIDEX
NASA Astrophysics Data System (ADS)
Rožnovský, Jaroslav; Litschmann, Tomáš; Středová, Hana; Středa, Tomáš; Salaš, Petr; Horká, Marie
2017-09-01
Urban environment differs from the surrounding landscape in terms of the values of meteorological parameters. This is often referred to as the urban heat island (UHI), which in simple terms means higher air temperatures in cities. The cause of these changes lies in the different active surfaces in cities, which subsequently results in a different radiation balance. The higher temperatures, however, also affect the living conditions in the city and during very high temperature periods can have negative effects on the health of the city inhabitants. The results presented in this paper are based on measurements taken over several years at locations near Hradec Králové, which is surrounded by different surface areas. Environment analysis was performed using the Humidex index. The obtained results show that replacing green areas with built-up areas affects temperatures in the city, when air temperatures are very high they significantly increase the discomfort of the inhabitants. Differences in the frequency of discomfort levels are observed especially during periods of high temperatures, at lower temperatures these differences are not significant. Higher frequencies of discomfort are observed at locations with artificial surfaces (asphalt, cobblestones, concrete) and in closed spaces. In contrast, locations with lots of green areas almost always have the value of this index lower or more balanced. The results should therefore be a valid argument for maintaining and extending green areas in cities.
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Microclimate and Hydrology of Native Cloud Forest in Hawaii Volcanoes National Park
NASA Astrophysics Data System (ADS)
Giambelluca, T. W.; Asner, G. P.; Martin, R. E.; Delay, J. K.; Mudd, R. G.; Nullet, M. A.; Takahashi, M.
2006-12-01
The water balance of cloud forests on Kilauea Volcano are of interest for improving understanding of regional hydrologic and ecological processes. Exceptionally high rates of forest evapotranspiration (ET) have been found in recent studies on other tropical oceanic islands, raising questions about current estimates of water balance and groundwater recharge for forested areas in Hawai'i. Previous studies in the same area have shown fog to be the dominant pathway for atmospheric nitrogen deposition derived from atmospheric sources associated with the nearby Pu'u O'o eruption. A 25-m tower equipped with eddy covariance and other micrometeorological instrumentation was constructed within 17-m-tall native Metrosideros polymorpha cloud forest in Hawai'i Volcanoes National Park. Measurements of stand-level ET, tree transpiration, throughfall, stemflow, and soil moisture are underway to quantify the canopy water balance and to estimate the direct deposition of cloud water to the system. Based on these measurements, mean monthly stand level ET is estimated to range from 1.69 (March) to 3.43 (July) mm per day. These rates are slightly lower than expected for this site, and much lower than rates recently found at forest sites on other tropical islands. The ratio of throughfall to gross rainfall was 1.096, 1.065, and 1.034 for 2004, 2005, and 2006, respectively. These values imply cloud water interception of approximately 600 to 1000 mm per year. Measurements of stemflow and sapflow have recently begun and will be useful in refining the canopy water balance and improving estimates of cloud water interception.
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Illustrating harvest effects on site microclimate in a high-elevation forest stand.
W.B. Fowler; T.D. Anderson
1987-01-01
Three-dimensional contour surfaces were drawn for physiologically active radiation (PAR) and air and soil temperatures from measurements taken at a high-elevation site (1450 m) near the crest of the Cascade Range in central Washington. Measurements in a clearcut were compared with measurements from an adjacent uncut stand. Data for 31 days in July and August 1985...
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[MICROCLIMATE CONDITION IN SUBWAY CARS IN THE SUMMER PERIOD OF THE YEAR].
Leksin, A G; Evlampieva, M N; Timoshenkova, E V; Morgunov, A V; Kaptsov, V A
2015-01-01
There are presented the results of the work, which aims to identify the relationship between the temperature of air in the salons of subway cars from the heat output of passengers in different people occupancy of cars during "peak hours", and to determine the efficacy offorced air handling regular ventilation or air conditioning system to remove the elevated heat load on passengers. In the work there was used the method of calculating the amount of heat output of 215 passengers (nominal fullness of the chamber) and the simulation method of heat and moisture output of the same number of passengers. The operating system of ventilation has been shown to fail to decline the average temperature of the air in the passenger compartment to the optimum values and most efficient approach for the reducing the heat load on the passengers is the use of air conditioning systems.
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Vegetation placement for summer built surface temperature moderation in an urban microclimate.
Millward, Andrew A; Torchia, Melissa; Laursen, Andrew E; Rothman, Lorne D
2014-06-01
Urban vegetation can mitigate increases in summer air temperature by reducing the solar gain received by buildings. To quantify the temperature-moderating influence of city trees and vine-covered buildings, a total of 13 pairs of temperature loggers were installed on the surfaces of eight buildings in downtown Toronto, Canada, for 6 months during the summer of 2008. One logger in each pair was shaded by vegetation while the other measured built surface temperature in full sunlight. We investigated the temperature-moderating benefits of solitary mature trees, clusters of trees, and perennial vines using a linear-mixed model and a multiple regression analysis of degree hour difference. We then assessed the temperature-moderating effect of leaf area, plant size and proximity to building, and plant location relative to solar path. During a period of high solar intensity, we measured an average temperature differential of 11.7 °C, with as many as 10-12 h of sustained cooler built surface temperatures. Vegetation on the west-facing aspect of built structures provided the greatest temperature moderation, with maximum benefit (peak temperature difference) occurring late in the afternoon. Large mature trees growing within 5 m of buildings showed the greatest ability to moderate built surface temperature, with those growing in clusters delivering limited additional benefit compared with isolated trees. Perennial vines proved as effective as trees at moderating rise in built surface temperature to the south and west sides of buildings, providing an attractive alternative to shade trees where soil volume and space are limited.
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Vegetation Placement for Summer Built Surface Temperature Moderation in an Urban Microclimate
NASA Astrophysics Data System (ADS)
Millward, Andrew A.; Torchia, Melissa; Laursen, Andrew E.; Rothman, Lorne D.
2014-06-01
Urban vegetation can mitigate increases in summer air temperature by reducing the solar gain received by buildings. To quantify the temperature-moderating influence of city trees and vine-covered buildings, a total of 13 pairs of temperature loggers were installed on the surfaces of eight buildings in downtown Toronto, Canada, for 6 months during the summer of 2008. One logger in each pair was shaded by vegetation while the other measured built surface temperature in full sunlight. We investigated the temperature-moderating benefits of solitary mature trees, clusters of trees, and perennial vines using a linear-mixed model and a multiple regression analysis of degree hour difference. We then assessed the temperature-moderating effect of leaf area, plant size and proximity to building, and plant location relative to solar path. During a period of high solar intensity, we measured an average temperature differential of 11.7 °C, with as many as 10-12 h of sustained cooler built surface temperatures. Vegetation on the west-facing aspect of built structures provided the greatest temperature moderation, with maximum benefit (peak temperature difference) occurring late in the afternoon. Large mature trees growing within 5 m of buildings showed the greatest ability to moderate built surface temperature, with those growing in clusters delivering limited additional benefit compared with isolated trees. Perennial vines proved as effective as trees at moderating rise in built surface temperature to the south and west sides of buildings, providing an attractive alternative to shade trees where soil volume and space are limited.
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Karnaukh, N G; Petrov, G A; Gapon, V A; Poslednichenko, I P; Shmidt, S E
1992-01-01
Inspection of the environment in manganese-alloyed steel production showed inadequate hygienic conditions of the technological processes employed. Air was more polluted by manganese oxides during the oxygen-converter process though their highest concentrations, 38 times exceeding the MAS, appeared during the casting of steel. An electric furnace coated by dust-noise-proof material and gas cleaning is preferable from a hygienic point of view. The influence of unfavourable microclimate, intensive infrared irradiation and loud noise on workers necessitates automation and mechanization of the process in order to improve the working conditions.
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Plant Succession at the Edges of Two Abandoned Cultivated Fields on the Arid Lands Ecology Reserve
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simmons, Sally A.; Rickard, William H.
How vegetation recovers from disturbances is an important question for land managers. We examined 500 m2 plots to determine the progress made by native herbaceous plant species in colonizing the edges of abandoned cultivated fields at different elevations and microclimates, but with similar soils in a big sagebrush/bluebunch wheatgrass steppe. Alien species, especially cheatgrass and cereal rye, were the major competitors to the natives. The native species with best potential for restoring steppe habitats were sulphur lupine, hawksbeard, bottlebrush squirreltail, needle-and-thread grass, Sandberg's bluegrass, and several lomatiums.
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[Rheumatoid arthritis and morbidity among wet spinning factory women workers].
Wysocki, Z; Janas, Z; Cichoń, L; Sikorzewski, M; Gregorowicz, H
1977-01-01
Two hundred ninety women employed in the wet spinning mill of the linen plants have been examined. Their average age and duration of employment were respectively 45 and 17,5 years. Examined women worked in specific microclimate including temperature from 24 degrees C to 25.3 degrees C and the moisture of air from 63,5 to 72,5%. Rheumatoid Arthritis in women working in wet spinning factory was the aim of this examination. It has been stated that these surroundings have no influence on that sort of disease.
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Heavy metal pollution in soils of abandoned mining areas (SE, Spain)
NASA Astrophysics Data System (ADS)
Martínez-Sánchez, M. J.; Pérez-Sirvent, C.; Molina, J.; Tudela, M. L.; Navarro, M. C.; García-Lorenzo, M. L.
2009-04-01
Elevated levels of heavy metals can be found in and around disused metalliferous mines due to discharge and dispersion of mine wastes into nearby agricultural soils, food crops and stream systems. Heavy metals contained in the residues from mining and metallurgical operations are often dispersed by wind and/or water after their disposal. These areas have severe erosion problems caused by wind and water runoff in which soil and mine spoil texture, landscape topography and regional and microclimate play an important role. The present study was carried out in the Cabezo Rajao (La Uni
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The global topography mission gains momentum
Farr, Tom; Evans, Diane; Zebker, Howard; Harding, David; Bufton, Jack; Dixon, Timothy; Vetrella, S.; Gesch, Dean B.
1995-01-01
An accurate description of the surface elevation of the Earth is of fundamental importance to many branches of Earth science. Continental topographic data are required for studies of hydrology, ecology, glaciology, geomorphology, and atmospheric circulation. For example, in hydrologic and terrestrial ecosystem studies, topography exerts significant control on intercepted solar radiation, water runoff and subsurface water inventory, microclimate, vegetation type and distribution, and soil development. The topography of the polar ice caps and mountain glaciers directly reflects ice-flow dynamics and is closely linked to global climate and sea level change.
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Makarov, V I; Tiurenkov, I N; Klauchek, S V; Nalivaĭko, I O; Antipova, A Iu
1997-01-01
A group of volunteers was exposed to action of heating microclimate (ambient temperature 30 +/- 1 degrees C, relative humidity 35 +/- 5%) and other critical occupation factors (physical loading, personal protective equipment). They received simultaneously one of the medicines: placebo, bemethyl (0.5 g), phenibut (0.25 g), obsidan (0.08 g), or phenibut (0.25 g) combined with obsidan (0.08 g). Combined phenibut (0.25 g) with obsidan (0.08 g) were proved to be the most effective method to increase stability of the human body against studying critical occupational factors.
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Wilkening, Jennifer L; Ray, Chris; Varner, Johanna
2015-01-01
The American pika (Ochotona princeps) is considered a sentinel species for detecting ecological effects of climate change. Pikas are declining within a large portion of their range, and ongoing research suggests loss of sub-surface ice as a mechanism. However, no studies have demonstrated physiological responses of pikas to sub-surface ice features. Here we present the first analysis of physiological stress in pikas living in and adjacent to habitats underlain by ice. Fresh fecal samples were collected non-invasively from two adjacent sites in the Rocky Mountains (one with sub-surface ice and one without) and analyzed for glucocorticoid metabolites (GCM). We also measured sub-surface microclimates in each habitat. Results indicate lower GCM concentration in sites with sub-surface ice, suggesting that pikas are less stressed in favorable microclimates resulting from sub-surface ice features. GCM response was well predicted by habitat characteristics associated with sub-surface ice features, such as lower mean summer temperatures. These results suggest that pikas inhabiting areas without sub-surface ice features are experiencing higher levels of physiological stress and may be more susceptible to changing climates. Although post-deposition environmental effects can confound analyses based on fecal GCM, we found no evidence for such effects in this study. Sub-surface ice features are key to water cycling and storage and will likely represent an increasingly important component of water resources in a warming climate. Fecal samples collected from additional watersheds as part of current pika monitoring programs could be used to further characterize relationships between pika stress and sub-surface ice features.
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Locosselli, Giuliano Maselli; Cardim, Ricardo Henrique; Ceccantini, Gregório
2016-05-01
We aimed to understand the effect of rock outcrops on the growth of Podocarpus lambertii within a microrefuge. Our hypothesis holds that the growth and survival of this species depend on the regional climate decoupling provided by rock outcrops. To test this hypothesis, we characterized the microclimate of (1) surrounding vegetation, (2) rock outcrop corridors, and (3) adjacencies. We assessed population structure by collecting data of specimen stem diameter and height. We also assessed differences between vegetation associated or not with outcrops using satellite imaging. For dendrochronological analyses, we sampled 42 individuals. Tree rings of 31 individuals were dated, and climate-growth relationships were tested. Rock outcrops produce a favorable microclimate by reducing average temperature by 4.9 °C and increasing average air humidity by 12 %. They also reduce the variability of atmospheric temperature by 42 % and air humidity by 20 % supporting a vegetation with higher leaf area index. Within this vegetation, specimen height was strongly constrained by the outcrop height. Although temperature and precipitation modulate this species growth, temperature-induced stress is the key limiting growth factor for this population of P. lambertii. We conclude that this species growth and survival depend on the presence of rock outcrops. These topography elements decouple regional climate in a favorable way for this species growth. However, these benefits are restricted to the areas sheltered by rock outcrops. Although this microrefuge supported P. lambertii growth so far, it is unclear whether this protection would be sufficient to withstand the stress of future climate changes.
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Biodegradable Plastic Mulch Films: Impacts on Soil Microbial Communities and Ecosystem Functions.
Bandopadhyay, Sreejata; Martin-Closas, Lluis; Pelacho, Ana M; DeBruyn, Jennifer M
2018-01-01
Agricultural plastic mulch films are widely used in specialty crop production systems because of their agronomic benefits. Biodegradable plastic mulches (BDMs) offer an environmentally sustainable alternative to conventional polyethylene (PE) mulch. Unlike PE films, which need to be removed after use, BDMs are tilled into soil where they are expected to biodegrade. However, there remains considerable uncertainty about long-term impacts of BDM incorporation on soil ecosystems. BDMs potentially influence soil microbial communities in two ways: first, as a surface barrier prior to soil incorporation, indirectly affecting soil microclimate and atmosphere (similar to PE films) and second, after soil incorporation, as a direct input of physical fragments, which add carbon, microorganisms, additives, and adherent chemicals. This review summarizes the current literature on impacts of plastic mulches on soil biological and biogeochemical processes, with a special emphasis on BDMs. The combined findings indicated that when used as a surface barrier, plastic mulches altered soil microbial community composition and functioning via microclimate modification, though the nature of these alterations varied between studies. In addition, BDM incorporation into soil can result in enhanced microbial activity and enrichment of fungal taxa. This suggests that despite the fact that total carbon input from BDMs is minuscule, a stimulatory effect on microbial activity may ultimately affect soil organic matter dynamics. To address the current knowledge gaps, long term studies and a better understanding of impacts of BDMs on nutrient biogeochemistry are needed. These are critical to evaluating BDMs as they relate to soil health and agroecosystem sustainability.
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Biodegradable Plastic Mulch Films: Impacts on Soil Microbial Communities and Ecosystem Functions
Bandopadhyay, Sreejata; Martin-Closas, Lluis; Pelacho, Ana M.; DeBruyn, Jennifer M.
2018-01-01
Agricultural plastic mulch films are widely used in specialty crop production systems because of their agronomic benefits. Biodegradable plastic mulches (BDMs) offer an environmentally sustainable alternative to conventional polyethylene (PE) mulch. Unlike PE films, which need to be removed after use, BDMs are tilled into soil where they are expected to biodegrade. However, there remains considerable uncertainty about long-term impacts of BDM incorporation on soil ecosystems. BDMs potentially influence soil microbial communities in two ways: first, as a surface barrier prior to soil incorporation, indirectly affecting soil microclimate and atmosphere (similar to PE films) and second, after soil incorporation, as a direct input of physical fragments, which add carbon, microorganisms, additives, and adherent chemicals. This review summarizes the current literature on impacts of plastic mulches on soil biological and biogeochemical processes, with a special emphasis on BDMs. The combined findings indicated that when used as a surface barrier, plastic mulches altered soil microbial community composition and functioning via microclimate modification, though the nature of these alterations varied between studies. In addition, BDM incorporation into soil can result in enhanced microbial activity and enrichment of fungal taxa. This suggests that despite the fact that total carbon input from BDMs is minuscule, a stimulatory effect on microbial activity may ultimately affect soil organic matter dynamics. To address the current knowledge gaps, long term studies and a better understanding of impacts of BDMs on nutrient biogeochemistry are needed. These are critical to evaluating BDMs as they relate to soil health and agroecosystem sustainability. PMID:29755440
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Large-Scale Removal of Invasive Honeysuckle Decreases Mosquito and Avian Host Abundance.
Gardner, Allison M; Muturi, Ephantus J; Overmier, Leah D; Allan, Brian F
2017-12-01
Invasive species rank second only to habitat destruction as a threat to native biodiversity. One consequence of biological invasions is altered risk of exposure to infectious diseases in human and animal populations. The distribution and prevalence of mosquito-borne diseases depend on the complex interactions between the vector, the pathogen, and the human or wildlife reservoir host. These interactions are highly susceptible to disturbance by invasive species, including terrestrial plants. We conducted a 2-year field experiment using a Before-After/Control-Impact design to examine how removal of invasive Amur honeysuckle (Lonicera maackii) in a forest fragment embedded within a residential neighborhood affects the abundance of mosquitoes, including two of the most important vectors of West Nile virus, Culex pipiens and Cx. restuans. We also assessed any potential changes in avian communities and local microclimate associated with Amur honeysuckle removal. We found that (1) removal of Amur honeysuckle reduces the abundance of both vector and non-vector mosquito species that commonly feed on human hosts, (2) the abundance and composition of avian hosts is altered by honeysuckle removal, and (3) areas invaded with honeysuckle support local microclimates that are favorable to mosquito survival. Collectively, our investigations demonstrate the role of a highly invasive understory shrub in determining the abundance and distribution of mosquitoes and suggest potential mechanisms underlying this pattern. Our results also give rise to additional questions regarding the general impact of invasive plants on vector-borne diseases and the spatial scale at which removal of invasive plants may be utilized to effect disease control.
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Applications of the thermography in the animal production
NASA Astrophysics Data System (ADS)
Piñeiro, Carlos; Vizcaino, Elena; Morales, Joaquín.; Manso, Alberto; Díaz, Immaculada; Montalvo, Gema
2015-04-01
Infrared thermography is a working technology for over decades, which have been applied mainly in the buildings. We want to move this use to the animal production in order to help us to detect problems of energy efficiency in the facilities preventing, for example, the animal's welfare. In animal production it is necessary to provide a suitable microclimate according to age and production stage of the animals. This microclimate is achieved in the facilities through the environment modification artificially, providing an appropriate comfort for the animals. Many of the problems detected in farms are related to a poor environmental management and control. This is where infrared thermography becomes an essential diagnostic tool to detect failures in the facilities that will be related with health and performance of the animals. The use of this technology in energy audits for buildings, facilities, etc. is becoming more frequent, enabling the technician to easily detect and assess the temperature and energy losses, and it can be used as a support to draft reports and to transmit the situation to the owner in a visual format. In this way, both will be able to decide what improvements are required. Until now, there was not an appropriate technology with affordable prices and easy to manage enough in order to allow the use of the thermography like a routine tool for the diagnostic of these problems, but currently there are some solutions which are starting to appear on the market to meet the requirements needed by the industry.
