Sample records for i forest ecosystem
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Foliar litter decomposition in an alpine forest meta-ecosystem on the eastern Tibetan Plateau.
Yue, Kai; Yang, Wanqin; Peng, Changhui; Peng, Yan; Zhang, Chuan; Huang, Chunping; Tan, Yu; Wu, Fuzhong
2016-10-01
Litter decomposition is a biological process fundamental to element cycling and a main nutrient source within forest meta-ecosystems, but few studies have looked into this process simultaneously in individual ecosystems, where environmental factors can vary substantially. A two-year field study conducted in an alpine forest meta-ecosystem with four litter species (i.e., willow: Salix paraplesia, azalea: Rhododendron lapponicum, cypress: Sabina saltuaria, and larch: Larix mastersiana) that varied widely in chemical traits showed that both litter species and ecosystem type (i.e., forest floor, stream and riparian zone) are important factors affecting litter decomposition, and their effects can be moderated by local-scale environmental factors such as temperature and nutrient availability. Litter decomposed fastest in the streams followed by the riparian zone and forest floor regardless of species. For a given litter species, both the k value and limit value varied significantly among ecosystems, indicating that the litter decomposition rate and extent (i.e., reaching a limit value) can be substantially affected by ecosystem type and the local-scale environmental factors. Apart from litter initial acid unhydrolyzable residue (AUR) concentration and its ratio to nitrogen concentration (i.e., AUR/N ratio), the initial nutrient concentrations of phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) were also important litter traits that affected decomposition depending on the ecosystem type. Copyright © 2016 Elsevier B.V. All rights reserved.
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Morris, Rebecca J.
2010-01-01
Huge areas of diverse tropical forest are lost or degraded every year with dramatic consequences for biodiversity. Deforestation and fragmentation, over-exploitation, invasive species and climate change are the main drivers of tropical forest biodiversity loss. Most studies investigating these threats have focused on changes in species richness or species diversity. However, if we are to understand the absolute and long-term effects of anthropogenic impacts on tropical forests, we should also consider the interactions between species, how those species are organized in networks, and the function that those species perform. I discuss our current knowledge of network structure and ecosystem functioning, highlighting empirical examples of their response to anthropogenic impacts. I consider the future prospects for tropical forest biodiversity, focusing on biodiversity and ecosystem functioning in secondary forest. Finally, I propose directions for future research to help us better understand the effects of anthropogenic impacts on tropical forest biodiversity. PMID:20980318
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i-Tree and urban FIA—what's the connection?
David J. Nowak
2015-01-01
The i-Tree program (www.itreetools.org) was developed to assess ecosystem services and values from trees and forests based on measured forest data. The i-Tree program is currently being integrated with FIA data to assess various ecosystem services and values from urban FIA data. This presentation will overview the history and use of i-Tree; the various tools of i-Tree...
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Alamgir, Mohammed; Turton, Stephen M; Macgregor, Colin J; Pert, Petina L
2016-10-01
As ecosystem services supply from tropical forests is declining due to deforestation and forest degradation, much effort is essential to sustain ecosystem services supply from tropical forested landscapes, because tropical forests provide the largest flow of multiple ecosystem services among the terrestrial ecosystems. In order to sustain multiple ecosystem services, understanding ecosystem services capacity across heterogeneous forest types and identifying certain ecosystem services that could be managed to leverage positive effects across the wider bundle of ecosystem services are required. We sampled three forest types, tropical rainforests, sclerophyll forests, and rehabilitated plantation forests, over an area of 32,000m(2) from Wet Tropics bioregion, Australia, aiming to compare supply and evaluate interactions and patterns of eight ecosystem services (global climate regulation, air quality regulation, erosion regulation, nutrient regulation, cyclone protection, habitat provision, energy provision, and timber provision). On average, multiple ecosystem services were highest in the rainforests, lowest in sclerophyll forests, and intermediate in rehabilitated plantation forests. However, a wide variation was apparent among the plots across the three forest types. Global climate regulation service had a synergistic impact on the supply of multiple ecosystem services, while nutrient regulation service was found to have a trade-off impact. Considering multiple ecosystem services, most of the rehabilitated plantation forest plots shared the same ordination space with rainforest plots in the ordination analysis, indicating that rehabilitated plantation forests may supply certain ecosystem services nearly equivalent to rainforests. Two synergy groups and one trade-off group were identified. Apart from conserving rainforests and sclerophyll forests, our findings suggest two additional integrated pathways to sustain the supply of multiple ecosystem services from a heterogeneous tropical forest landscape: (i) rehabilitation of degraded forests aiming to provide global climate regulation and habitat provision ecosystem services and (ii) management intervention to sustain global climate regulation and habitat provision ecosystem services. Copyright © 2016 Elsevier B.V. All rights reserved.
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The Northwest Forest Plan as a model for broad-scale ecosystem management: a social perspective.
Susan Charnley
2006-01-01
I evaluated the Northwest Forest Plan as a model for ecosystem management to achieve social and economic goals in communities located around federal forests in the US. Pacific Northwest. My assessment is based on the results of socioeconomic monitoring conducted to evaluate progress in achieving the plan's goals during its past 10 years. The assessment criteria I...
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The Northwest Forest Plan as a model for broad-scale ecosystem management: a social perspective.
Susan Charnely
2006-01-01
I evaluated the Northwest Forest Plan as a model for ecosystem management to achieve social and economic goals in communities located around federal forests in the U.S. Pacific Northwest. My assessment is based on the results of socioeconomic monitoring conducted to evaluate progress in achieving the plan's goals during its past 10 years. The assessment criteria I...
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Shanlei Sun; Ge Sun; Peter Caldwell; Steven G. McNulty; Erika Cohen; Jingfeng Xiao; Yang Zhang
2015-01-01
Understanding and quantitatively evaluating the regional impacts of climate change and variability (e.g., droughts) on forest ecosystem functions (i.e., water yield, evapotranspiration, and productivity) and services (e.g., fresh water supply and carbon sequestration) is of great importance for developing climate change adaptation strategies for National Forests and...
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Hisano, Masumi; Searle, Eric B; Chen, Han Y H
2018-02-01
Forest ecosystems are critical to mitigating greenhouse gas emissions through carbon sequestration. However, climate change has affected forest ecosystem functioning in both negative and positive ways, and has led to shifts in species/functional diversity and losses in plant species diversity which may impair the positive effects of diversity on ecosystem functioning. Biodiversity may mitigate climate change impacts on (I) biodiversity itself, as more-diverse systems could be more resilient to climate change impacts, and (II) ecosystem functioning through the positive relationship between diversity and ecosystem functioning. By surveying the literature, we examined how climate change has affected forest ecosystem functioning and plant diversity. Based on the biodiversity effects on ecosystem functioning (B→EF), we specifically address the potential for biodiversity to mitigate climate change impacts on forest ecosystem functioning. For this purpose, we formulate a concept whereby biodiversity may reduce the negative impacts or enhance the positive impacts of climate change on ecosystem functioning. Further B→EF studies on climate change in natural forests are encouraged to elucidate how biodiversity might influence ecosystem functioning. This may be achieved through the detailed scrutiny of large spatial/long temporal scale data sets, such as long-term forest inventories. Forest management strategies based on B→EF have strong potential for augmenting the effectiveness of the roles of forests in the mitigation of climate change impacts on ecosystem functioning. © 2017 Cambridge Philosophical Society.
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NASA Astrophysics Data System (ADS)
Asbjornsen, H.; Guerrieri, R.; Belmecheri, S.; Martin, M.; Lepine, L. C.; Jennings, K.; Xiao, J.; Ollinger, S. V.
2016-12-01
Understanding relations among forest carbon (C) uptake and water use is critical for predicting forest-climate interactions. Water use efficiency (WUE), the carbon (C) gain per unit of water (H2O) loss through transpiration, is the key physiological trait linking C and H2O cycling in forests, and allowing to monitor ecosystem productivity in response to climate change. Stable C isotope composition (δ13C) in tree rings has been extensively used to assess the changes in the tree-level intrinsic WUE (i.e., iWUE - photosynthesis, A/stomatal conductance, gs) in response to climate and anthropogenic forcing (e.g., increase in atmospheric CO2 and nitrogen deposition) over the last century for several forest ecosystems worldwide. At the forest ecosystem level, WUE (WUEe) is obtained as ratio between Gross Primary Productivity (GPP) and evapotranspiration (ET), derived from the eddy covariance measurements. Very few studies compared the two approaches, most of them to date have focused on within-site comparisons. Moreover, most studies examining the influence of climatic factors on tree-WUE have focused on water-limited ecosystems in the Southwest, while much less is known about the dynamics of WUE for mesic forests in the Eastern US. In this study, we compared the two methods across a range of eight to eleven forested Ameriflux sites and climate in the U.S. Furthermore, we examined whether species-specific physiological mechanisms facilitated a better understanding of the ecosystem fluxes. We will present 30-year δ13C (and derived iWUE) and δ18O tree-ring chronologies and foliar isotopes obtained from two dominant species at each site. Spatial (across sites) and temporal trend of tree WUE will then be compared to ecosystem WUE as obtained from eddy covariance data. Relationships between δ13C and δ18O will be explored to elucidate the species-specific physiological mechanisms underlying variation in iWUE. Moreover, drivers of the changes in WUE at the two scales (i.e., tree and ecosystem) will be evaluated and discussed in relations to findings from previous studies. Finally, we will explore the relationship between patterns of leaf internal CO2 (ci)-regulation in response to rising atmospheric CO2, which is one of the major causes of disagreement between the tree and ecosystem level approaches.
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An individual-based process model to simulate landscape-scale forest ecosystem dynamics
Rupert Seidl; Werner Rammer; Robert M. Scheller; Thomas Spies
2012-01-01
Forest ecosystem dynamics emerges from nonlinear interactions between adaptive biotic agents (i.e., individual trees) and their relationship with a spatially and temporally heterogeneous abiotic environment. Understanding and predicting the dynamics resulting from these complex interactions is crucial for the sustainable stewardship of ecosystems, particularly in the...
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Andrew R. Neill; Klaus J. Puettmann; Adrian Ares
2013-01-01
To understand the impacts of overstory density reductions on resilience of forest ecosystems (i.e., the capacity of an ecosystem to maintain desired ecosystem functions in a fl uctuating environment), we examined overstory basal area and understory vegetation cover and richness collected 6 years after thinning in seven 40- to 60-year-old forests dominated by Douglas-fi...
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Beyond CO2 - Tackling the full greenhouse gas budget of a sub-alpine forest ecosystem
NASA Astrophysics Data System (ADS)
Burri, Susanne; Merbold, Lutz; Meier, Philip; Eugster, Werner; Hörtnagl, Lukas; Buchmann, Nina
2017-04-01
In order to tackle the full greenhouse gas (GHG) budgets of forest ecosystems, it is desirable but challenging to quantify the three major GHGs, i.e. CO2, CH4 and N2O simultaneously in-situ. At the long-term forest research site Davos (Candidate Class I Ecosystem Station within the Integrated Carbon Observation System - ICOS), we have recently installed a state-of-the-art measuring system simultaneously to observe the three GHGs on a high temporal resolution and both within and above the forest canopy. Thereby, we combine above-canopy eddy covariance flux measurements and forest floor chamber flux measurements (using five custom-made fully automated chambers). Both systems are connected to a quantum cascade laser absorption spectrometer (QCL, Aerodyne) and measurements are switched between three hours of above-canopy and one hour of forest floor GHG flux measurements. Using this approach, we will be able to study the full GHG budget as well as the dynamics of the individual fluxes on two vertical levels within the forest using a single instrument. The first results presented here will highlight the suitability of this promising tool for quantifying the full GHG budget of forest ecosystems.
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Clarifying the confusion: old-growth savannahs and tropical ecosystem degradation
2016-01-01
Ancient tropical grassy biomes are often misrecognized as severely degraded forests. I trace this confusion to several factors, with roots in the nineteenth century, including misinterpretations of the nature of fire in savannahs, attempts to reconcile savannah ecology with Clementsian succession, use of physiognomic (structural) definitions of savannah and development of tropical degradation frameworks focused solely on forests. Towards clarity, I present two models that conceptualize the drivers of ecosystem degradation as operating in both savannahs and forests. These models highlight how human-induced environmental changes create ecosystems with superficially similar physiognomies but radically different conservation values. Given the limitation of physiognomy to differentiate savannahs from severely degraded forests, I present an alternative approach based on floristic composition. Data from eastern lowland Bolivia show that old-growth savannahs can be reliably distinguished by eight grass species and that species identity influences ecosystem flammability. I recommend that scientists incorporate savannahs in tropical degradation frameworks alongside forests, and that savannah be qualified as old-growth savannah in reference to ancient grassy biomes or derived savannah in reference to deforestation. These conceptual advances will require attention not only to tree cover, but also to savannah herbaceous plant species and their ecologies. This article is part of the themed issue ‘Tropical grassy biomes: linking ecology, human use and conservation’. PMID:27502372
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The Impacts of Climate-Induced Drought on Biogeochemical Cycles
NASA Astrophysics Data System (ADS)
Peng, C.
2014-12-01
Terrestrial ecosystems and, in particular, forests exert strong controls on the global biogeochemical cycles and influence regional hydrology and climatology directly through water and surface energy budgets. Recent studies indicated that forest mortality caused by rising temperature and drought from around the world have unexpectedly increased in the past decade and they collectively illustrate the vulnerability of many forested ecosystems to rapid increases in tree mortality due to warmer temperatures and more severe drought. Persistent changes in tree mortality rates can alter forest structure, composition, and ecosystem services (such as albedo and carbon sequestration). Quantifying potential impacts of tree mortality on ecosystem processes requires research into mortality effects on carbon, energy, and water budgets at both site and regional levels. Despite recent progress, the uncertainty around mortality responses still limits our ability to predict the likelihood and anticipate the impacts of tree die-off. Studies are needed that explore tree death physiology for a wide variety of functional types, connect patterns of mortality with climate events, and quantify the impacts on carbon, energy, and water flux. In this presentation, I will highlight recent research progress, and identify key research needs and future challenges to predict the consequence and impacts of drought-induced large-scale forest mortality on biogeochemical cycles. I will focus on three main forest ecosystems (tropic rainforest in Amazon, temperate forest in Western USA, and boreal forest in Canada) as detailed case studies.
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Regeneration of southern pine stands under ecosystem management in the Piedmont
James W. McMinn; Alexander Clark
1999-01-01
Ecosystem-oriented management is being used on southern National Forests to conserve biodiversity, improve the balance among forest values, and achieve sustainable conditions. This paper reports on the regeneration phase of a study to identify the implications of ecosystem management practices on loblolly pine (Pinus taeda L.) and shortleaf (I? echinata Mill) pine...
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[Ecological regulation services of Hainan Island ecosystem and their valuation].
Ouyang, Zhiyun; Zhao, Tongqian; Zhao, Jingzhu; Xiao, Han; Wang, Xiaoke
2004-08-01
Ecosystem services imply the natural environmental conditions on which human life relies for existence, and their effectiveness formed and sustained by ecosystem and its ecological processes. In newly research reports, they were divided into four groups, i. e., provisioning services, regulation services, cultural services, and supporting services. To assess and valuate ecosystem services is the foundation of regional environmental reserve and development. Taking Hainan Island as an example and based on the structure and processes of natural ecosystem, this paper discussed the proper methods for regulation services assessment. The ecosystems were classified into 13 types including valley rain forest, mountainous rain forest, tropical monsoon forest, mountainous coppice forest, mountainous evergreen forest, tropical coniferous forest, shrubs, plantation, timber forest, windbreak forest, mangrove, savanna, and cropland, and then, the regulation services and their economic values of Hainan Island ecosystem were assessed and evaluated by terms of water-holding, soil conservancy, nutrient cycle, C fixation, and windbreak function. The economic value of the regulation services of Hainan Island ecosystem was estimated as 2035.88 x 10(8)-2153.39 x 10(8) RMB yuan, 8 times higher to its provisioning services (wood and agricultural products) which were estimated as only 254.06 x 10(8) RMB yuan. The result implied that ecosystem regulation services played an even more important role in the sustainable development of society and economy in Hainan Island.
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Divergence of ecosystem services in U.S. National Forests and Grasslands under a changing climate
Kai Duan; Ge Sun; Shanlei Sun; Peter V. Caldwell; Erika Cohen Mack; Steve McNulty; Heather D. Aldridge; Yang Zhang
2016-01-01
The 170 National Forests and Grasslands (NFs) in the conterminous United States are public lands that provide important ecosystem services such as clean water and timber supply to the American people. This study investigates the potential impacts of climate change on two key ecosystem functions (i.e., water yield and ecosystem productivity) using the most recent...
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[Forest ecosystem service and its evaluation in China].
Fang, Jin; Lu, Shaowei; Yu, Xinxiao; Rao, Liangyi; Niu, Jianzhi; Xie, Yuanyuan; Zhag, Zhenming
2005-08-01
Facing the relative lag of forest ecosystem service and estimation in China, this paper proposed to quickly carry out the research on the evaluation of forest ecosystem service. On the basis of the classification of forest ecosystem types in China, the service of artificial and semi-artificial forest ecosystems was investigated, which was divided into eight types, i.e., timber and other products, recreation and eco-tourism, water storage, C fixation and O2 release, nutrient cycling, air quality purifying, erosion control, and habitat provision. According to the assessment index system for global ecosystem service proposed by Costanza et al., a series of assessment index system suitable for Chinese forest ecosystem service was set up, by which, the total value of forest ecosystem service in China was estimated to be 30 601.20 x 10(8) yuan x yr(-1), including direct and indirect economic value about 1 920.23 x 10(8) and 28 680.97 x 10(8) yuan x yr(-1), respectively. The indirect value was as 14.94 times as the direct one. The research aimed to bring natural resources and environment factors into the account system of national economy quickly, and to realize the green GDP at last, which would be helpful to realize sustainable development and environment protection.
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Repelling invaders: Hawaiian foresters use ecology to counter invasive species
Jim Kling; Julie Featured: Denslow; Tracy Johnson; Susan Cordell
2008-01-01
The Hawaiian Islands are one of the United States' most treasured natural resources. Their natural beauty attracts legions of visitors every year, and they represent a unique set of ecosystems. Despite their limited geographic size, Hawaiâi hosts a remarkable range of habitats. On some islands, dry tropical forest, wet rain forest, and alpine ecosystems are found...
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Mueller-Dombois, Dieter; Jacobi, James D.; Boehmer, Hans Juergen; Price, Jonathan P.
2013-01-01
In the early 1970s, a multidisciplinary team of forest biologists began a study of Hawaiian ecosystems under the International Biological Program (IBP). Research focus was on the intact native ecosystems in and around Hawai'i Volcanoes National Park, in particular the ʻŌhiʻa Lehua rainforest. Patches of dead ʻŌhiʻa stands had been reported from the windward slopes of Mauna Loa and Mauna Kea. Subsequent air photo analyses by a team of US and Hawai'i State foresters discovered rapidly spreading ʻŌhiʻa dieback, also called ʻŌhiʻa forest decline. A killer disease was suspected to destroy the Hawaiian rain forest in the next 15-25 years. Ecological research continued with a focus on the dynamics of the Hawaiian rainforest. This book explains what really happened and why the ʻŌhiʻa rainforest survived in tact as everyone can witness today.
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Schleuning, Matthias; Farwig, Nina; Peters, Marcell K; Bergsdorf, Thomas; Bleher, Bärbel; Brandl, Roland; Dalitz, Helmut; Fischer, Georg; Freund, Wolfram; Gikungu, Mary W; Hagen, Melanie; Garcia, Francisco Hita; Kagezi, Godfrey H; Kaib, Manfred; Kraemer, Manfred; Lung, Tobias; Naumann, Clas M; Schaab, Gertrud; Templin, Mathias; Uster, Dana; Wägele, J Wolfgang; Böhning-Gaese, Katrin
2011-01-01
Forest fragmentation and selective logging are two main drivers of global environmental change and modify biodiversity and environmental conditions in many tropical forests. The consequences of these changes for the functioning of tropical forest ecosystems have rarely been explored in a comprehensive approach. In a Kenyan rainforest, we studied six animal-mediated ecosystem processes and recorded species richness and community composition of all animal taxa involved in these processes. We used linear models and a formal meta-analysis to test whether forest fragmentation and selective logging affected ecosystem processes and biodiversity and used structural equation models to disentangle direct from biodiversity-related indirect effects of human disturbance on multiple ecosystem processes. Fragmentation increased decomposition and reduced antbird predation, while selective logging consistently increased pollination, seed dispersal and army-ant raiding. Fragmentation modified species richness or community composition of five taxa, whereas selective logging did not affect any component of biodiversity. Changes in the abundance of functionally important species were related to lower predation by antbirds and higher decomposition rates in small forest fragments. The positive effects of selective logging on bee pollination, bird seed dispersal and army-ant raiding were direct, i.e. not related to changes in biodiversity, and were probably due to behavioural changes of these highly mobile animal taxa. We conclude that animal-mediated ecosystem processes respond in distinct ways to different types of human disturbance in Kakamega Forest. Our findings suggest that forest fragmentation affects ecosystem processes indirectly by changes in biodiversity, whereas selective logging influences processes directly by modifying local environmental conditions and resource distributions. The positive to neutral effects of selective logging on ecosystem processes show that the functionality of tropical forests can be maintained in moderately disturbed forest fragments. Conservation concepts for tropical forests should thus include not only remaining pristine forests but also functionally viable forest remnants.
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Schleuning, Matthias; Farwig, Nina; Peters, Marcell K.; Bergsdorf, Thomas; Bleher, Bärbel; Brandl, Roland; Dalitz, Helmut; Fischer, Georg; Freund, Wolfram; Gikungu, Mary W.; Hagen, Melanie; Garcia, Francisco Hita; Kagezi, Godfrey H.; Kaib, Manfred; Kraemer, Manfred; Lung, Tobias; Schaab, Gertrud; Templin, Mathias; Uster, Dana; Wägele, J. Wolfgang; Böhning-Gaese, Katrin
2011-01-01
Forest fragmentation and selective logging are two main drivers of global environmental change and modify biodiversity and environmental conditions in many tropical forests. The consequences of these changes for the functioning of tropical forest ecosystems have rarely been explored in a comprehensive approach. In a Kenyan rainforest, we studied six animal-mediated ecosystem processes and recorded species richness and community composition of all animal taxa involved in these processes. We used linear models and a formal meta-analysis to test whether forest fragmentation and selective logging affected ecosystem processes and biodiversity and used structural equation models to disentangle direct from biodiversity-related indirect effects of human disturbance on multiple ecosystem processes. Fragmentation increased decomposition and reduced antbird predation, while selective logging consistently increased pollination, seed dispersal and army-ant raiding. Fragmentation modified species richness or community composition of five taxa, whereas selective logging did not affect any component of biodiversity. Changes in the abundance of functionally important species were related to lower predation by antbirds and higher decomposition rates in small forest fragments. The positive effects of selective logging on bee pollination, bird seed dispersal and army-ant raiding were direct, i.e. not related to changes in biodiversity, and were probably due to behavioural changes of these highly mobile animal taxa. We conclude that animal-mediated ecosystem processes respond in distinct ways to different types of human disturbance in Kakamega Forest. Our findings suggest that forest fragmentation affects ecosystem processes indirectly by changes in biodiversity, whereas selective logging influences processes directly by modifying local environmental conditions and resource distributions. The positive to neutral effects of selective logging on ecosystem processes show that the functionality of tropical forests can be maintained in moderately disturbed forest fragments. Conservation concepts for tropical forests should thus include not only remaining pristine forests but also functionally viable forest remnants. PMID:22114695
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Seidl, Rupert; Rammer, Werner; Spies, Thomas A.
2015-01-01
Disturbances are key drivers of forest ecosystem dynamics, and forests are well adapted to their natural disturbance regimes. However, as a result of climate change, disturbance frequency is expected to increase in the future in many regions. It is not yet clear how such changes might affect forest ecosystems, and which mechanisms contribute to (current and future) disturbance resilience. We studied a 6364-ha landscape in the western Cascades of Oregon, USA, to investigate how patches of remnant old-growth trees (as one important class of biological legacies) affect the resilience of forest ecosystems to disturbance. Using the spatially explicit, individual-based, forest landscape model iLand, we analyzed the effect of three different levels of remnant patches (0%, 12%, and 24% of the landscape) on 500-year recovery trajectories after a large, high-severity wildfire. In addition, we evaluated how three different levels of fire frequency modulate the effects of initial legacies. We found that remnant live trees enhanced the recovery of total ecosystem carbon (TEC) stocks after disturbance, increased structural complexity of forest canopies, and facilitated the recolonization of late-seral species (LSS). Legacy effects were most persistent for indicators of species composition (still significant 500 years after disturbance), while TEC (i.e., a measure of ecosystem functioning) was least affected, with no significant differences among legacy scenarios after 236 years. Compounding disturbances were found to dampen legacy effects on all indicators, and higher initial legacy levels resulted in elevated fire severity in the second half of the study period. Overall, disturbance frequency had a stronger effect on ecosystem properties than the initial level of remnant old-growth trees. A doubling of the historically observed fire frequency to a mean fire return interval of 131 years reduced TEC by 10.5% and lowered the presence of LSS on the landscape by 18.1% on average, demonstrating that an increase in disturbance frequency (a potential climate change effect) may considerably alter the structure, composition, and functioning of forest landscapes. Our results indicate that live tree legacies are an important component of disturbance resilience, underlining the potential of retention forestry to address challenges in ecosystem management. PMID:27053913
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We have developed a modeling framework to support grid-based simulation of ecosystems at multiple spatial scales, the Ecological Component Library for Parallel Spatial Simulation (ECLPSS). ECLPSS helps ecologists to build robust spatially explicit simulations of ...
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NASA Astrophysics Data System (ADS)
Mayer, Paul M.
2008-03-01
Identifying the biotic (e.g. decomposers, vegetation) and abiotic (e.g. temperature, moisture) mechanisms controlling litter decomposition is key to understanding ecosystem function, especially where variation in ecosystem structure due to successional processes may alter the strength of these mechanisms. To identify these controls and feedbacks, I measured mass loss and N flux in herbaceous, leaf, and wood litter along a successional gradient of ecosystem types (old field, transition forest, old-growth forest) while manipulating detritivore access to litter. Ecosystem type, litter type, and decomposers contributed directly and interactively to decomposition. Litter mass loss and N accumulation was higher while litter C:N remained lower in old-growth forests than in either old fields or transition forest. Old-growth forests influenced litter dynamics via microclimate (coolest and wettest) but also, apparently, through a decomposer community adapted to consuming the large standing stocks of leaf litter, as indicated by rapid leaf litter loss. In all ecosystem types, mass loss of herbaceous litter was greater than leaf litter which, in turn was greater than wood. However, net N loss from wood litter was faster than expected, suggesting localized N flux effects of wood litter. Restricting detritivore access to litter reduced litter mass loss and slowed the accumulation of N in litter, suggesting that macro-detritivores affect both physical and chemical characteristics of litter through selective grazing. These data suggest that the distinctive litter loss rates and efficient N cycling observed in old-growth forest ecosystems are not likely to be realized soon after old fields are restored to forested ecosystems.
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NASA Astrophysics Data System (ADS)
Wang, Shaoqiang
2014-05-01
Evidence is mounting that an increase in extreme climate events has begun to occur worldwide during the recent decades, which affect biosphere function and biodiversity. Ecosystems returned to its original structures and functions to maintain its sustainability, which was closely dependent on ecosystem resilience. Understanding the resilience and recovery capacity of ecosystem to extreme climate events is essential to predicting future ecosystem responses to climate change. Given the overwhelming importance of this region in the overall carbon cycle of forest ecosystems in China, south China suffered a destructive ice storm in 2008. In this study, we used the number of freezing day and a process-based model (Boreal Ecosystem Productivity Simulator, BEPS) to characterize the spatial distribution of ice storm region in southeastern China and explore the impacts on carbon cycle of forest ecosystem over the past decade. The ecosystem variables, i.e. Net primary productivity (NPP), Evapotranspiration (ET), and Water use efficiency (WUE, the ratio of NPP to ET) from the outputs of BEPS models were used to detect the resistance and resilience of forest ecosystem in southern China. The pattern of ice storm-induced forest productivity widespread decline was closely related to the number of freezing day during the ice storm period. The NPP of forest area suffered heavy ice storm returned to normal status after five months with high temperature and ample moisture, indicated a high resilience of subtropical forest in China. The long-term changes of forest WUE remain stable, behaving an inherent sensitivity of ecosystem to extreme climate events. In addition, ground visits suggested that the recovery of forest productivity was attributed to rapid growth of understory. Understanding the variability and recovery threshold of ecosystem following extreme climate events help us to better simulate and predict the variability of ecosystem structure and function under current and future climate change.
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P. Sicard; A. Augustaitis; S. Belyazid; C. Calfapietra; A. De Marco; Mark E. Fenn; Andrzej Bytnerowicz; Nancy Grulke; S. He; R. Matyssek; Y. Serengil; G. Wieser; E. Paoletti
2016-01-01
Research directions from the 27th conference for Specialists in Air Pollution and Climate Change Effects on Forest Ecosystems (2015) reflect knowledge advancements about (i) Mechanistic bases of tree responses to multiple climate and pollution stressors, in particular the interaction of ozone (O3) with nitrogen (N) deposition and drought; (ii)...
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Natural disturbance impacts on ecosystem services and biodiversity in temperate and boreal forests.
Thom, Dominik; Seidl, Rupert
2016-08-01
In many parts of the world forest disturbance regimes have intensified recently, and future climatic changes are expected to amplify this development further in the coming decades. These changes are increasingly challenging the main objectives of forest ecosystem management, which are to provide ecosystem services sustainably to society and maintain the biological diversity of forests. Yet a comprehensive understanding of how disturbances affect these primary goals of ecosystem management is still lacking. We conducted a global literature review on the impact of three of the most important disturbance agents (fire, wind, and bark beetles) on 13 different ecosystem services and three indicators of biodiversity in forests of the boreal, cool- and warm-temperate biomes. Our objectives were to (i) synthesize the effect of natural disturbances on a wide range of possible objectives of forest management, and (ii) investigate standardized effect sizes of disturbance for selected indicators via a quantitative meta-analysis. We screened a total of 1958 disturbance studies published between 1981 and 2013, and reviewed 478 in detail. We first investigated the overall effect of disturbances on individual ecosystem services and indicators of biodiversity by means of independence tests, and subsequently examined the effect size of disturbances on indicators of carbon storage and biodiversity by means of regression analysis. Additionally, we investigated the effect of commonly used approaches of disturbance management, i.e. salvage logging and prescribed burning. We found that disturbance impacts on ecosystem services are generally negative, an effect that was supported for all categories of ecosystem services, i.e. supporting, provisioning, regulating, and cultural services (P < 0.001). Indicators of biodiversity, i.e. species richness, habitat quality and diversity indices, on the other hand were found to be influenced positively by disturbance (P < 0.001). Our analyses thus reveal a 'disturbance paradox', documenting that disturbances can put ecosystem services at risk while simultaneously facilitating biodiversity. A detailed investigation of disturbance effect sizes on carbon storage and biodiversity further underlined these divergent effects of disturbance. While a disturbance event on average causes a decrease in total ecosystem carbon by 38.5% (standardized coefficient for stand-replacing disturbance), it on average increases overall species richness by 35.6%. Disturbance-management approaches such as salvage logging and prescribed burning were neither found significantly to mitigate negative effects on ecosystem services nor to enhance positive effects on biodiversity, and thus were not found to alleviate the disturbance paradox. Considering that climate change is expected to intensify natural disturbance regimes, our results indicate that biodiversity will generally benefit from such changes while a sustainable provisioning of ecosystem services might come increasingly under pressure. This underlines that disturbance risk and resilience require increased attention in ecosystem management in the future, and that new approaches to addressing the disturbance paradox in management are needed. © 2015 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.
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Pérez-Izquierdo, Leticia; Zabal-Aguirre, Mario; Flores-Rentería, Dulce; González-Martínez, Santiago C; Buée, Marc; Rincón, Ana
2017-04-01
Fungi provide relevant ecosystem services contributing to primary productivity and the cycling of nutrients in forests. These fungal inputs can be decisive for the resilience of Mediterranean forests under global change scenarios, making necessary an in-deep knowledge about how fungal communities operate in these ecosystems. By using high-throughput sequencing and enzymatic approaches, we studied the fungal communities associated with three genotypic variants of Pinus pinaster trees, in 45-year-old common garden plantations. We aimed to determine the impact of biotic (i.e., tree genotype) and abiotic (i.e., season, site) factors on the fungal community structure, and to explore whether structural shifts triggered functional responses affecting relevant ecosystem processes. Tree genotype and spatial-temporal factors were pivotal structuring fungal communities, mainly by influencing their assemblage and selecting certain fungi. Diversity variations of total fungal community and of that of specific fungal guilds, together with edaphic properties and tree's productivity, explained relevant ecosystem services such as processes involved in carbon turnover and phosphorous mobilization. A mechanistic model integrating relations of these variables and ecosystem functional outcomes is provided. Our results highlight the importance of structural shifts in fungal communities because they may have functional consequences for key ecosystem processes in Mediterranean forests. © 2017 Society for Applied Microbiology and John Wiley and Sons Ltd.
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Urban Forest Ecosystem Service Optimization, Tradeoffs, and Disparities
NASA Astrophysics Data System (ADS)
Bodnaruk, E.; Kroll, C. N.; Endreny, T. A.; Hirabayashi, S.; Yang, Y.
2014-12-01
Urban land area and the proportion of humanity living in cities is growing, leading to increased urban air pollution, temperature, and stormwater runoff. These changes can exacerbate respiratory and heat-related illnesses and affect ecosystem functioning. Urban trees can help mitigate these threats by removing air pollutants, mitigating urban heat island effects, and infiltrating and filtering stormwater. The urban environment is highly heterogeneous, and there is no tool to determine optimal locations to plant or protect trees. Using spatially explicit land cover, weather, and demographic data within biophysical ecosystem service models, this research expands upon the iTree urban forest tools to produce a new decision support tool (iTree-DST) that will explore the development and impacts of optimal tree planting. It will also heighten awareness of environmental justice by incorporating the Atkinson Index to quantify disparities in health risks and ecosystem services across vulnerable and susceptible populations. The study area is Baltimore City, a location whose urban forest and environmental justice concerns have been studied extensively. The iTree-DST is run at the US Census block group level and utilizes a local gradient approach to calculate the change in ecosystem services with changing tree cover across the study area. Empirical fits provide ecosystem service gradients for possible tree cover scenarios, greatly increasing the speed and efficiency of the optimization procedure. Initial results include an evaluation of the performance of the gradient method, optimal planting schemes for individual ecosystem services, and an analysis of tradeoffs and synergies between competing objectives.
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Forest structure in low diversity tropical forests: a study of Hawaiian wet and dry forests
R. Ostertag; F. Inman-Narahari; S. Cordell; C.P. Giardina; L. Sack
2014-01-01
The potential influence of diversity on ecosystem structure and function remains a topic of significant debate, especially for tropical forests where diversity can range widely. We used Center for Tropical Forest Science (CTFS) methodology to establish forest dynamics plots in montane wet forest and lowland dry forest on Hawaiâi Island. We compared the species...
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NASA Astrophysics Data System (ADS)
Fu, W. J.; Jiang, P. K.; Zhou, G. M.; Zhao, K. L.
2014-04-01
Spatial pattern information of carbon density in forest ecosystem including forest litter carbon (FLC) plays an important role in evaluating carbon sequestration potentials. The spatial variation of FLC density in the typical subtropical forests in southeastern China was investigated using Moran's I, geostatistics and a geographical information system (GIS). A total of 839 forest litter samples were collected based on a 12 km (south-north) × 6 km (east-west) grid system in Zhejiang province. Forest litter carbon density values were very variable, ranging from 10.2 kg ha-1 to 8841.3 kg ha-1, with an average of 1786.7 kg ha-1. The aboveground biomass had the strongest positive correlation with FLC density, followed by forest age and elevation. Global Moran's I revealed that FLC density had significant positive spatial autocorrelation. Clear spatial patterns were observed using local Moran's I. A spherical model was chosen to fit the experimental semivariogram. The moderate "nugget-to-sill" (0.536) value revealed that both natural and anthropogenic factors played a key role in spatial heterogeneity of FLC density. High FLC density values were mainly distributed in northwestern and western part of Zhejiang province, which were related to adopting long-term policy of forest conservation in these areas, while Hang-Jia-Hu (HJH) Plain, Jin-Qu (JQ) Basin and coastal areas had low FLC density due to low forest coverage and intensive management of economic forests. These spatial patterns were in line with the spatial-cluster map described by local Moran's I. Therefore, Moran's I, combined with geostatistics and GIS, could be used to study spatial patterns of environmental variables related to forest ecosystem.
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Jeremy Pinto; Anthony S. Davis; James J. K. Leary; Matthew M. Aghai
2015-01-01
Restoring degraded mesic-montane forests represents a major challenge in maintaining functioning ecosystems throughout the tropics. A key example of this lies in Hawaiâi, where restoring native koa (Acacia koa, A. Gray) forests are a top conservation and forestry priority because of the critical habitat and high-value timber products that they provide. Efforts...
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Soil water storage and daily dynamics of typical ecosystems in Heihe Watershed, China
NASA Astrophysics Data System (ADS)
Huang, Y.
2017-12-01
Soil water plays a key role in terrestrial ecosystems by controlling exchange processes among soil, vegetation, and atmosphere. The spatiotemporal distribution and dynamics of soil water storage (SWS) may provide information on the exchange of soil moisture among landscapes and between groundwater and surface water. The Heihe River Watershed (HRW) is a typical inland river basin located in the arid region of Northwestern China. Based on the soil water data automatically recorded every 30 min in 18 sites during the Heihe Water Allied Telemetry Experimental Research, the soil water dynamic of six typical ecosystems, i.e., alpine meadow, mountain coniferous forest, mountain steppe, temperate desert, riparian forest, and cropland, were analyzed. The 2m-depth soil water storage of cropland in growing season was highest, followed by riparian forest, alpine meadow, mountain coniferous forest, and mountain steppe, and that of temperate desert was the lowest. For alpine meadow, mountain coniferous forest, and desert ecosystems, the seasonal fluctuation of soil water content was obvious in 0-100cm depth but not in 100-200cm depth. For mountain steppe, cropland, and riparian forest ecosystems, there were obviously seasonal fluctuation in soil water content in all 0-200cm depth. In addition, the frequency distributions of 30-min soil water contents of the six ecosystems were different greatly. Together with rainfall, the soil water content was greatly affected by irrigation and seasonal frozen.
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Impact of biomass harvesting on forest soil productivity in the northern Rocky Mountains
Woongsoon Jang; Christopher R. Keyes; Deborah Page-Dumroese
2015-01-01
Biomass harvesting extracts an increased amount of organic matter from forest ecosystems over conventional harvesting. Since organic matter plays a critical role in forest productivity, concerns of potential negative long-term impacts of biomass harvesting on forest productivity (i.e., changing nutrient/water cycling, aggravating soil properties, and compaction) have...
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Assessing Forest NPP: BIOME-BGC Predictions versus BEF Derived Estimates
NASA Astrophysics Data System (ADS)
Hasenauer, H.; Pietsch, S. A.; Petritsch, R.
2007-05-01
Forest productivity has always been a major issue within sustainable forest management. While in the past terrestrial forest inventory data have been the major source for assessing forest productivity, recent developments in ecosystem modeling offer an alternative approach using ecosystem models such as Biome-BGC to estimate Net Primary Production (NPP). In this study we compare two terrestrial driven approaches for assessing NPP: (i) estimates from a species specific adaptation of the biogeochemical ecosystem model BIOME-BGC calibrated for Alpine conditions; and (ii) NPP estimates derived from inventory data using biomass expansion factors (BEF). The forest inventory data come from 624 sample plots across Austria and consist of repeated individual tree observations and include growth as well as soil and humus information. These locations are covered with spruce, beech, oak, pine and larch stands, thus addressing the main Austrian forest types. 144 locations were previously used in a validating effort to produce species-specific parameter estimates of the ecosystem model. The remaining 480 sites are from the Austrian National Forest Soil Survey carried out at the Federal Research and Training Centre for Forests, Natural Hazards and Landscape (BFW). By using diameter at breast height (dbh) and height (h) volume and subsequently biomass of individual trees were calculated, aggregated for the whole forest stand and compared with the model output. Regression analyses were performed for both volume and biomass estimates.
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Forest structure in low-diversity tropical forests: a study of Hawaiian wet and dry forests.
Ostertag, Rebecca; Inman-Narahari, Faith; Cordell, Susan; Giardina, Christian P; Sack, Lawren
2014-01-01
The potential influence of diversity on ecosystem structure and function remains a topic of significant debate, especially for tropical forests where diversity can range widely. We used Center for Tropical Forest Science (CTFS) methodology to establish forest dynamics plots in montane wet forest and lowland dry forest on Hawai'i Island. We compared the species diversity, tree density, basal area, biomass, and size class distributions between the two forest types. We then examined these variables across tropical forests within the CTFS network. Consistent with other island forests, the Hawai'i forests were characterized by low species richness and very high relative dominance. The two Hawai'i forests were floristically distinct, yet similar in species richness (15 vs. 21 species) and stem density (3078 vs. 3486/ha). While these forests were selected for their low invasive species cover relative to surrounding forests, both forests averaged 5->50% invasive species cover; ongoing removal will be necessary to reduce or prevent competitive impacts, especially from woody species. The montane wet forest had much larger trees, resulting in eightfold higher basal area and above-ground biomass. Across the CTFS network, the Hawaiian montane wet forest was similar to other tropical forests with respect to diameter distributions, density, and aboveground biomass, while the Hawai'i lowland dry forest was similar in density to tropical forests with much higher diversity. These findings suggest that forest structural variables can be similar across tropical forests independently of species richness. The inclusion of low-diversity Pacific Island forests in the CTFS network provides an ∼80-fold range in species richness (15-1182 species), six-fold variation in mean annual rainfall (835-5272 mm yr(-1)) and 1.8-fold variation in mean annual temperature (16.0-28.4°C). Thus, the Hawaiian forest plots expand the global forest plot network to enable testing of ecological theory for links among species diversity, environmental variation and ecosystem function.
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Forest Structure in Low-Diversity Tropical Forests: A Study of Hawaiian Wet and Dry Forests
Ostertag, Rebecca; Inman-Narahari, Faith; Cordell, Susan; Giardina, Christian P.; Sack, Lawren
2014-01-01
The potential influence of diversity on ecosystem structure and function remains a topic of significant debate, especially for tropical forests where diversity can range widely. We used Center for Tropical Forest Science (CTFS) methodology to establish forest dynamics plots in montane wet forest and lowland dry forest on Hawai‘i Island. We compared the species diversity, tree density, basal area, biomass, and size class distributions between the two forest types. We then examined these variables across tropical forests within the CTFS network. Consistent with other island forests, the Hawai‘i forests were characterized by low species richness and very high relative dominance. The two Hawai‘i forests were floristically distinct, yet similar in species richness (15 vs. 21 species) and stem density (3078 vs. 3486/ha). While these forests were selected for their low invasive species cover relative to surrounding forests, both forests averaged 5–>50% invasive species cover; ongoing removal will be necessary to reduce or prevent competitive impacts, especially from woody species. The montane wet forest had much larger trees, resulting in eightfold higher basal area and above-ground biomass. Across the CTFS network, the Hawaiian montane wet forest was similar to other tropical forests with respect to diameter distributions, density, and aboveground biomass, while the Hawai‘i lowland dry forest was similar in density to tropical forests with much higher diversity. These findings suggest that forest structural variables can be similar across tropical forests independently of species richness. The inclusion of low-diversity Pacific Island forests in the CTFS network provides an ∼80-fold range in species richness (15–1182 species), six-fold variation in mean annual rainfall (835–5272 mm yr−1) and 1.8-fold variation in mean annual temperature (16.0–28.4°C). Thus, the Hawaiian forest plots expand the global forest plot network to enable testing of ecological theory for links among species diversity, environmental variation and ecosystem function. PMID:25162731
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This EnviroAtlas dataset contains points depicting the location of market-based programs, referred to herein as markets, and projects addressing ecosystem services protection in the United States. The data were collected via surveys and desk research conducted by Forest Trends' Ecosystem Marketplace from 2008 to 2016 on biodiversity (i.e., imperiled species/habitats; wetlands and streams), carbon, and water markets. Additional biodiversity data were obtained from the Regulatory In-lieu Fee and Bank Information Tracking System (RIBITS) database in 2015. Points represent the centroids (i.e., center points) of market coverage areas, project footprints, or project primary impact areas in which ecosystem service markets or projects operate. National-level markets are an exception to this norm with points representing administrative headquarters locations. Attribute data include information regarding the methodology, design, and development of biodiversity, carbon, and water markets and projects. This dataset was produced by Forest Trends' Ecosystem Marketplace for EnviroAtlas in order to support public access to and use of information related to environmental markets. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) o
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Forest Restoration and Parasitoid Wasp Communities in Montane Hawai’i
Gould, Rachelle K.; Pejchar, Liba; Bothwell, Sara G.; Brosi, Berry; Wolny, Stacie; Mendenhall, Chase D.; Daily, Gretchen
2013-01-01
Globally, most restoration efforts focus on re-creating the physical structure (flora or physical features) of a target ecosystem with the assumption that other ecosystem components will follow. Here we investigate that assumption by documenting biogeographical patterns in an important invertebrate taxon, the parasitoid wasp family Ichneumonidae, in a recently reforested Hawaiian landscape. Specifically, we test the influence of (1) planting configurations (corridors versus patches), (2) vegetation age, (3) distance from mature native forest, (4) surrounding tree cover, and (5) plant community composition on ichneumonid richness, abundance, and composition. We sampled over 7,000 wasps, 96.5% of which were not native to Hawai’i. We found greater relative richness and abundance of ichneumonids, and substantially different communities, in restored areas compared to mature forest and abandoned pasturelands. Non-native ichneumonids drive these differences; restored areas and native forest did not differ in native ichneumonid abundance. Among restored areas, ichneumonid communities did not differ by planting age or configuration. As tree cover increased within 120 m of a sampling point, ichneumonid community composition increasingly resembled that found in native forest. Similarly, native ichneumonid abundance increased with proximity to native forest. Our results suggest that restoration plantings, if situated near target forest ecosystems and in areas with higher local tree cover, can facilitate restoration of native fauna even in a highly invaded system. PMID:23527171
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Forest restoration and parasitoid wasp communities in montane Hawai'i.
Gould, Rachelle K; Pejchar, Liba; Bothwell, Sara G; Brosi, Berry; Wolny, Stacie; Mendenhall, Chase D; Daily, Gretchen
2013-01-01
Globally, most restoration efforts focus on re-creating the physical structure (flora or physical features) of a target ecosystem with the assumption that other ecosystem components will follow. Here we investigate that assumption by documenting biogeographical patterns in an important invertebrate taxon, the parasitoid wasp family Ichneumonidae, in a recently reforested Hawaiian landscape. Specifically, we test the influence of (1) planting configurations (corridors versus patches), (2) vegetation age, (3) distance from mature native forest, (4) surrounding tree cover, and (5) plant community composition on ichneumonid richness, abundance, and composition. We sampled over 7,000 wasps, 96.5% of which were not native to Hawai'i. We found greater relative richness and abundance of ichneumonids, and substantially different communities, in restored areas compared to mature forest and abandoned pasturelands. Non-native ichneumonids drive these differences; restored areas and native forest did not differ in native ichneumonid abundance. Among restored areas, ichneumonid communities did not differ by planting age or configuration. As tree cover increased within 120 m of a sampling point, ichneumonid community composition increasingly resembled that found in native forest. Similarly, native ichneumonid abundance increased with proximity to native forest. Our results suggest that restoration plantings, if situated near target forest ecosystems and in areas with higher local tree cover, can facilitate restoration of native fauna even in a highly invaded system.
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Susan Frankel
2009-01-01
On behalf of the Fourth Phytophthoras in Forest and Natural Ecosystems local organizing committee and co-chairs Everett Hansen, Clive Brasier, and Giles Hardy, I thank you for your contributions to this Working Party meeting. The past week has stimulated much thought and discussion, thanks to the 100 participants from 15 countries, 48 papers and 31 posters, two field...
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Baró, Francesc; Chaparro, Lydia; Gómez-Baggethun, Erik; Langemeyer, Johannes; Nowak, David J; Terradas, Jaume
2014-05-01
Mounting research highlights the contribution of ecosystem services provided by urban forests to quality of life in cities, yet these services are rarely explicitly considered in environmental policy targets. We quantify regulating services provided by urban forests and evaluate their contribution to comply with policy targets of air quality and climate change mitigation in the municipality of Barcelona, Spain. We apply the i-Tree Eco model to quantify in biophysical and monetary terms the ecosystem services "air purification," "global climate regulation," and the ecosystem disservice "air pollution" associated with biogenic emissions. Our results show that the contribution of urban forests regulating services to abate pollution is substantial in absolute terms, yet modest when compared to overall city levels of air pollution and GHG emissions. We conclude that in order to be effective, green infrastructure-based efforts to offset urban pollution at the municipal level have to be coordinated with territorial policies at broader spatial scales.
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This EnviroAtlas web service contains layers depicting market-based programs and projects addressing ecosystem services protection in the United States. Layers include data collected via surveys and desk research conducted by Forest Trends' Ecosystem Marketplace from 2008 to 2016 on biodiversity (i.e., imperiled species/habitats; wetlands and streams), carbon, and water markets and enabling conditions that facilitate, directly or indirectly, market-based approaches to protecting and investing in those ecosystem services. This dataset was produced by Forest Trends' Ecosystem Marketplace for EnviroAtlas in order to support public access to and use of information related to environmental markets. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).
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NASA Astrophysics Data System (ADS)
Widicahyono, A.; Awang, S. A.; Maryudi, A.; Setiawan, M. A.; Rusdimi, A. U.; Handoko, D.; Muhammad, R. A.
2018-04-01
Over the last decade, deforestation in Indonesia has reduced the forest area down to more than 6 million hectares. There is conflict that the protected forest ecosystem service is still often perceived as public goods. Many of them went unrecognized in planning process and continue to be undervalued. The challenge lies in maintaining socioeconomic development and ecosystem services sustainability without overlooking the people’s opportunities and improving their livelihoods over the long term. An integrated approach is required to understand the comprehensive concept of protected forest ecosystem service. This research aims to formulate a scheme of payment for ecosystem service (PES) in a protected forest. It is a first step towards the attempt for the value of ecosystem services to be reflected in decision-making. Literatures, previous researches and secondary data are reviewed thoroughly to analyze the interrelated components by looking at the environment as a whole and recognize their linkages that have consequences to one another both positive and negative. The framework of implementation of PES schemes outlines the complexity of human-environment interconnecting relationships. It evaluates the contributing actors of different interest i.e. long term use and short term use. The concept of PES accommodates the fulfillment of both conservation and exploitation with an incentive scheme to the contributing parties who are willing to implement conservation and issuance of compensation expense for any exploitation means. The most crucial part in this concept is to have a good and effective communication between every policy makers concerning the forest ecosystem and local communities.
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[Effects of small hydropower substitute fuel project on forest ecosystem services].
Yu, Hai Yan; Zha, Tong Gang; Nie, Li Shui; Lyu, Zhi Yuan
2016-10-01
Based on the Forest Ecosystem Services Assessment Standards (LY/T 1721－2008) issued by the State Forestry Administration, this paper evaluated four key functions of forest ecosystems, i.e., water conservation, soil conservation, carbon fixation and oxygen release, and nutrient accumulation. Focusing on the project area of Majiang County in Guizhou Province, this study provided some quantitative evidence that the implementation of the small hydropower substituting fuel project had positive effects on the values and material quantities of ecosystem service functions. The results showed that the small hydropower substituting fuel project had a significant effect on the increase of forest ecosystem services. Water conservation quantity of Pinus massoniana and Cupressus funebris plantations inside project area was 20662.04 m 3 ·hm -2 ·a -1 , 20.5% higher than outside project area, with soil conservation quantity of 119.1 t·hm -2 ·a -1 , 29.7% higher than outside project area, carbon fixation and oxygen release of 220.49 t·hm -2 ·a -1 , 40.2% higher than outside project area, and forest tree nutrition accumulation of 3.49 t·hm -2 ·a -1 , 48.5% higher than outside project area. Small hydropower substituting fuel project for increasing the quota of forest ecosystem service function value was in the order of carbon fixation and oxygen release function (71400 yuan·hm -2 ·a -1 ) > water conservation function (60100 yuan·hm -2 ·a -1 ) > tree nutrition accumulation function (13800 yuan·hm -2 ·a -1 ) > soil conservation function (8100 yuan·hm -2 ·a -1 ). Small hydropower substituting fuel project played an important role for improving the forest ecological service function value and realizing the sustainable development of forest.
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NASA Astrophysics Data System (ADS)
de Chant, Timothy Paul
Forests and woodlands are integral parts of ecosystems across the globe, but they are threatened by a variety of factors, including urbanization and introduced forest pathogens. These two forces are fundamentally altering ecosystems, both by removing forest cover and reshaping landscapes. Comprehending how these two processes have changed forest ecosystems is an important step toward understanding how the affected systems will function in the future. I investigated the range of edge effects that result from disturbance brought about by forest pathogens and urbanization in two coastal oak woodlands in Marin County, California. Oak woodlands are a dynamic part of California's landscape, reacting to changes in their biotic and abiotic environments across a range of spatial and temporal scales. Sudden Oak Death, caused by the introduced forest pathogen Phytophthora ramorum, has led to widespread mortality of many tree species in California's oak woodlands. I investigated how the remaining trees respond to such rapid changes in canopy structure (Chapter 2), and my results revealed a forest canopy quick to respond to the new openings. Urbanization, another disturbance regime, operates on a longer time scale. Immediately following urban development, forest edges are strikingly linear, but both forest processes and homeowner actions likely work in concert to disrupt the straight edge (Chapter 3). Forest edges grew more sinuous within 14 years of the initial disturbance, and continued to do so for the remainder of the study, another 21 years. Individual Quercus agrifolia trees also respond to urban edges decades after disturbance (Chapter 4), and their reaction is reflected in declining stable carbon isotope values (delta13C). This change suggests trees may have increased their stomatal conductance in response to greater water availability, reduced their photosynthetic rate as a result of stress, or some combination of both. Edges have far reaching and long lasting effects on forest structure and function. Investigations of their impacts on multiple spatial and temporal scales are important in determining the range of effects they have on forest ecosystems. Studies that combine remote sensing, geographic information systems, and field studies may help us understand the ecological consequences of forest edges.
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Future directions for forest restoration in Hawai'i
James B. Friday; Susan Cordell; Christian P. Giardina; Faith Inman-Narahari; Nicholas Koch; James J. K. Leary; Creighton M. Litton; Clay Trauernicht
2015-01-01
Hawaiâi has served as a model system for studies of nutrient cycling and conservation biology. The islands may also become a laboratory for exploring new approaches to forest restoration because of a common history of degradation and the growing number of restoration projects undertaken. Approximately half of the native ecosystems of Hawaiâi have been converted to non-...
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Thomas A. Spies; Paul F. Hessburg; Carl N. Skinner; Klaus J. Puettmann; Matthew J. Reilly; Raymond J. Davis; Jane A. Kertis; Jonathan W. Long; David C. . Shaw
2018-01-01
In this chapter, we examine the scientific basis of the assumptions, management strategies, and goals of the Northwest Forest Plan (NWFP, or Plan) relative to the ecology of old-growth forests, forest successional dynamics, and disturbance processes. Our emphasis is on âcoarse-filterâ approaches to conservation (i.e., those that are concerned with entire ecosystems,...
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Scott R. Abella
2009-01-01
Trees in many forests affect the soils and plants below their canopies. In current high-density southwestern ponderosa pine (Pinus ponderosa) forests, managers have opportunities to enhance multiple ecosystem values by manipulating tree density, distribution, and canopy cover through tree thinning. I performed a study in northern Arizona ponderosa...
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A large-scale forest fragmentation experiment: the Stability of Altered Forest Ecosystems Project.
Ewers, Robert M; Didham, Raphael K; Fahrig, Lenore; Ferraz, Gonçalo; Hector, Andy; Holt, Robert D; Kapos, Valerie; Reynolds, Glen; Sinun, Waidi; Snaddon, Jake L; Turner, Edgar C
2011-11-27
Opportunities to conduct large-scale field experiments are rare, but provide a unique opportunity to reveal the complex processes that operate within natural ecosystems. Here, we review the design of existing, large-scale forest fragmentation experiments. Based on this review, we develop a design for the Stability of Altered Forest Ecosystems (SAFE) Project, a new forest fragmentation experiment to be located in the lowland tropical forests of Borneo (Sabah, Malaysia). The SAFE Project represents an advance on existing experiments in that it: (i) allows discrimination of the effects of landscape-level forest cover from patch-level processes; (ii) is designed to facilitate the unification of a wide range of data types on ecological patterns and processes that operate over a wide range of spatial scales; (iii) has greater replication than existing experiments; (iv) incorporates an experimental manipulation of riparian corridors; and (v) embeds the experimentally fragmented landscape within a wider gradient of land-use intensity than do existing projects. The SAFE Project represents an opportunity for ecologists across disciplines to participate in a large initiative designed to generate a broad understanding of the ecological impacts of tropical forest modification.
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A large-scale forest fragmentation experiment: the Stability of Altered Forest Ecosystems Project
Ewers, Robert M.; Didham, Raphael K.; Fahrig, Lenore; Ferraz, Gonçalo; Hector, Andy; Holt, Robert D.; Kapos, Valerie; Reynolds, Glen; Sinun, Waidi; Snaddon, Jake L.; Turner, Edgar C.
2011-01-01
Opportunities to conduct large-scale field experiments are rare, but provide a unique opportunity to reveal the complex processes that operate within natural ecosystems. Here, we review the design of existing, large-scale forest fragmentation experiments. Based on this review, we develop a design for the Stability of Altered Forest Ecosystems (SAFE) Project, a new forest fragmentation experiment to be located in the lowland tropical forests of Borneo (Sabah, Malaysia). The SAFE Project represents an advance on existing experiments in that it: (i) allows discrimination of the effects of landscape-level forest cover from patch-level processes; (ii) is designed to facilitate the unification of a wide range of data types on ecological patterns and processes that operate over a wide range of spatial scales; (iii) has greater replication than existing experiments; (iv) incorporates an experimental manipulation of riparian corridors; and (v) embeds the experimentally fragmented landscape within a wider gradient of land-use intensity than do existing projects. The SAFE Project represents an opportunity for ecologists across disciplines to participate in a large initiative designed to generate a broad understanding of the ecological impacts of tropical forest modification. PMID:22006969
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NASA Astrophysics Data System (ADS)
Gu, Huan
Urban forests play an important role in the urban ecosystem by providing a range of ecosystem services. Characterization of forest structure, species variation and growth in urban forests is critical for understanding the status, function and process of urban ecosystems, and helping maximize the benefits of urban ecosystems through management. The development of methods and applications to quantify urban forests using remote sensing data has lagged the study of natural forests due to the heterogeneity and complexity of urban ecosystems. In this dissertation, I quantify and map forest structure, species gradients and forest growth in an urban area using discrete-return lidar, airborne imaging spectroscopy and thermal infrared data. Specific objectives are: (1) to demonstrate the utility of leaf-off lidar originally collected for topographic mapping to characterize and map forest structure and associated uncertainties, including aboveground biomass, basal area, diameter, height and crown size; (2) to map species gradients using forest structural variables estimated from lidar and foliar functional traits, vegetation indices derived from AVIRIS hyperspectral imagery in conjunction with field-measured species data; and (3) to identify factors related to relative growth rates in aboveground biomass in the urban forests, and assess forest growth patterns across areas with varying degree of human interactions. The findings from this dissertation are: (1) leaf-off lidar originally acquired for topographic mapping provides a robust, potentially low-cost approach to quantify spatial patterns of forest structure and carbon stock in urban areas; (2) foliar functional traits and vegetation indices from hyperspectral data capture gradients of species distributions in the heterogeneous urban landscape; (3) species gradients, stand structure, foliar functional traits and temperature are strongly related to forest growth in the urban forests; and (4) high uncertainties in our ability to map forest structure, species gradient and growth rate occur in residential neighborhoods and along forest edges. Maps generated from this dissertation provide estimates of broad-scale spatial variations in forest structure, species distributions and growth to the city forest managers. The associated maps of uncertainty help managers understand the limitations of the maps and identify locations where the maps are more reliable and where more data are needed.
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Using iTree Model in Clark County, Nevada
Ecosystem services are the services and benefits that human populations obtain from nature. Whether surrounded by a forested, coastal, or urban area, ecosystems provide recreation, food, shelter, cleaner air and water. As the climate and environment change due to human activity,...
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NASA Astrophysics Data System (ADS)
Fisk, J.; Hurtt, G. C.; le page, Y.; Patel, P. L.; Chini, L. P.; Sahajpal, R.; Dubayah, R.; Thomson, A. M.; Edmonds, J.; Janetos, A. C.
2013-12-01
Integrated assessment models (IAMs) simulate the interactions between human and natural systems at a global scale, representing a broad suite of phenomena across the global economy, energy system, land-use, and carbon cycling. Most proposed climate mitigation strategies rely on maintaining or enhancing the terrestrial carbon sink as a substantial contribution to restrain the concentration of greenhouse gases in the atmosphere, however most IAMs rely on simplified regional representations of terrestrial carbon dynamics. Our research aims to reduce uncertainties associated with forest modeling within integrated assessments, and to quantify the impacts of climate change on forest growth and productivity for integrated assessments of terrestrial carbon management. We developed the new Integrated Ecosystem Demography (iED) to increase terrestrial ecosystem process detail, resolution, and the utilization of remote sensing in integrated assessments. iED brings together state-of-the-art models of human society (GCAM), spatial land-use patterns (GLM) and terrestrial ecosystems (ED) in a fully coupled framework. The major innovative feature of iED is a consistent, process-based representation of ecosystem dynamics and carbon cycle throughout the human, terrestrial, land-use, and atmospheric components. One of the most challenging aspects of ecosystem modeling is to provide accurate initialization of land surface conditions to reflect non-equilibrium conditions, i.e., the actual successional state of the forest. As all plants in ED have an explicit height, it is one of the few ecosystem models that can be initialized directly with vegetation height data. Previous work has demonstrated that ecosystem model resolution and initialization data quality have a large effect on flux predictions at continental scales. Here we use a factorial modeling experiment to quantify the impacts of model integration, process detail, model resolution, and initialization data on projections of future climate mitigation strategies. We find substantial effects on key integrated assessment projections including the magnitude of emissions to mitigate, the economic value of ecosystem carbon storage, future land-use patterns, food prices and energy technology.
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Quantifying tropical dry forest type and succession: substantial improvement with LiDAR
Sebastian Martinuzzi; William A. Gould; Lee A. Vierling; Andrew T. Hudak; Ross F. Nelson; Jeffrey S. Evans
2012-01-01
Improved technologies are needed to advance our knowledge of the biophysical and human factors influencing tropical dry forests, one of the worldâs most threatened ecosystems. We evaluated the use of light detection and ranging (LiDAR) data to address two major needs in remote sensing of tropical dry forests, i.e., classification of forest types and delineation of...
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A simple method for estimating gross carbon budgets for vegetation in forest ecosystems.
Ryan, Michael G.
1991-01-01
Gross carbon budgets for vegetation in forest ecosystems are difficult to construct because of problems in scaling flux measurements made on small samples over short periods of time and in determining belowground carbon allocation. Recently, empirical relationships have been developed to estimate total belowground carbon allocation from litterfall, and maintenance respiration from tissue nitrogen content. I outline a method for estimating gross carbon budgets using these empirical relationships together with data readily available from ecosystem studies (aboveground wood and canopy production, aboveground wood and canopy biomass, litterfall, and tissue nitrogen contents). Estimates generated with this method are compared with annual carbon fixation estimates from the Forest-BGC model for a lodgepole pine (Pinus contorta Dougl.) and a Pacific silver fir (Abies amabilis Dougl.) chronosequence.
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Tree species diversity mitigates disturbance impacts on the forest carbon cycle.
Silva Pedro, Mariana; Rammer, Werner; Seidl, Rupert
2015-03-01
Biodiversity fosters the functioning and stability of forest ecosystems and, consequently, the provision of crucial ecosystem services that support human well-being and quality of life. In particular, it has been suggested that tree species diversity buffers ecosystems against the impacts of disturbances, a relationship known as the "insurance hypothesis". Natural disturbances have increased across Europe in recent decades and climate change is expected to amplify the frequency and severity of disturbance events. In this context, mitigating disturbance impacts and increasing the resilience of forest ecosystems is of growing importance. We have tested how tree species diversity modulates the impact of disturbance on net primary production and the total carbon stored in living biomass for a temperate forest landscape in Central Europe. Using the simulation model iLand to study the effect of different disturbance regimes on landscapes with varying levels of tree species richness, we found that increasing diversity generally reduces the disturbance impact on carbon storage and uptake, but that this effect weakens or even reverses with successional development. Our simulations indicate a clear positive relationship between diversity and resilience, with more diverse systems experiencing lower disturbance-induced variability in their trajectories of ecosystem functioning. We found that positive effects of tree species diversity are mainly driven by an increase in functional diversity and a modulation of traits related to recolonization and resource usage. The results of our study suggest that increasing tree species diversity could mitigate the effects of intensifying disturbance regimes on ecosystem functioning and improve the robustness of forest carbon storage and the role of forests in climate change mitigation.
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Criterion 3: Maintenance of forest ecosystem health and vitality
Stephen R. Shifley; Francisco X. Aguilar; Nianfu Song; Susan I. Stewart; David J. Nowak; Dale D. Gormanson; W. Keith Moser; Sherri Wormstead; Eric J. Greenfield
2012-01-01
Forest ecosystem health depends on stable forest composition and structure and on sustainable ecosystem processes. Forest disturbances that push an ecosystem beyond the range of conditions considered normal can upset the balance among processes, exacerbate forest health problems, and increase mortality beyond historical norms. Sometimes forest ecosystems respond to...
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Urban forest ecosystem analysis using fused airborne hyperspectral and lidar data
NASA Astrophysics Data System (ADS)
Alonzo, Mike Gerard
Urban trees are strategically important in a city's effort to mitigate their carbon footprint, heat island effects, air pollution, and stormwater runoff. Currently, the most common method for quantifying urban forest structure and ecosystem function is through field plot sampling. However, taking intensive structural measurements on private properties throughout a city is difficult, and the outputs from sample inventories are not spatially explicit. The overarching goal of this dissertation is to develop methods for mapping urban forest structure and function using fused hyperspectral imagery and waveform lidar data at the individual tree crown scale. Urban forest ecosystem services estimated using the USDA Forest Service's i-Tree Eco (formerly UFORE) model are based largely on tree species and leaf area index (LAI). Accordingly, tree species were mapped in my Santa Barbara, California study area for 29 species comprising >80% of canopy. Crown-scale discriminant analysis methods were introduced for fusing Airborne Visible Infrared Imaging Spectrometry (AVIRIS) data with a suite of lidar structural metrics (e.g., tree height, crown porosity) to maximize classification accuracy in a complex environment. AVIRIS imagery was critical to achieving an overall species-level accuracy of 83.4% while lidar data was most useful for improving the discrimination of small and morphologically unique species. LAI was estimated at both the field-plot scale using laser penetration metrics and at the crown scale using allometry. Agreement of the former with photographic estimates of gap fraction and the latter with allometric estimates based on field measurements was examined. Results indicate that lidar may be used reasonably to measure LAI in an urban environment lacking in continuous canopy and characterized by high species diversity. Finally, urban ecosystem services such as carbon storage and building energy-use modification were analyzed through combination of aforementioned methods and the i-Tree Eco modeling framework. The remote sensing methods developed in this dissertation will allow researchers to more precisely constrain urban ecosystem spatial analyses and equip cities to better manage their urban forest resource.
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Harmony Dalgleish; C. Dana Nelson; John Scrivani; Douglass Jacobs
2015-01-01
Restoration of foundation species, such as the American chestnut (Castanea dentata) that was devastated by an introduced fungus, can restore ecosystem function. Understanding both the current distribution as well as biogeographic patterns is important for restoration planning. We used United States Department of Agriculture Forest...
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Analysis of laser altimeter waveforms for forested ecosystems of Central Florida
NASA Astrophysics Data System (ADS)
Weishampel, John F.; Harding, David J.; Boutet, Jeffry C., Jr.; Drake, Jason B.
1997-07-01
An experimental profiling airborne laser altimeter system developed at NASA's Goddard Space Flight Center was used to acquire vertical canopy data from several ecosystem types from The Nature Conservancy's Disney Wilderness Preserve, near Kissimmee, Florida. This laser altimeter, besides providing submeter accuracy of tree height, captures a profile of data which relates to the magnitude of reflectivity of the laser pulse as it penetrates different elevations of the forest canopy. This complete time varying amplitude of the return signal of the laser pulse, between the first (i.e., the canopy top) and last (i.e., the ground) returns, yields a waveform which is related to canopy architecture, specifically the nadir-projected vertical distribution of the surface of canopy components (i.e., foliage, twigs, and branches). Selected profile returns from representative covertypes (e.g., pine flatwoods, bayhead, and cypress wetland) were compared with ground truthed forest composition (i.e., species and size class distribution) and structural (i.e., canopy height, canopy closure, crown depth) measures to help understand how these properties contribute to variation in the altimeter waveform.
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Functional role of the herbaceous layer in eastern deciduous forest
Katherine J. Elliott; James M. Vose; Jennifer D. Knoepp; Barton D. Clinton; Brian D. Kloeppel
2014-01-01
The importance of the herbaceous layer in regulating ecosystem processes in deciduous forests is generally unknown. We use a manipulative study in a rich, mesophytic cove forest in the southern Appalachians to test the following hypotheses: (i) the herbaceous functional group (HFG) in mesophytic coves accelerates carbon and nutrient cycling, (ii) high litter quality...
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Ge Sun; Steven McNulty; Jianbiao Lu; James Vose; Devendra Amayta; Guoyi Zhou; Zhiqiang Zhang
2006-01-01
Watershed management and restoration practices require a clear understanding of the basic eco-hydrologic processes and ecosystem responses to disturbances at multiple scales (Bruijnzeel, 2004; Scott et al., 2005). Worldwide century-long forest hydrologic research has documented that deforestation and forestation (i.e. reforestation and afforestation) can have variable...
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Regional forest fragmentation effects on bottomland hardwood community types and resource values
Victor A. Rudis
1995-01-01
In human-dominated regions, forest vegetation removal impacts remaining ecosystems but regional-scale biological consequences and resource value changes are not well known. Using forest resource survey data, I examined current bottomland hardwood community types and a range of fragment size classes in the south central United States. Analyses examined resource value...
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Urban forest sustainability in the United States
David J. Nowak
2017-01-01
Urban forests in the United States provide numerous ecosystem services that vary in magnitude across the country and are valued in the billions of dollars per year. Urban tree cover has been on the decline in recent years. Numerous forces for change will continue to alter urban forests in the coming years (i.e., development, climate change, insects and diseases,...
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Escárraga, Mayron E; Lattke, John E; Azevedo, Celso O
2017-11-10
The male of the endangered ant Dinoponera lucida Emery is described, providing morphometric measurements, high-resolution images, and a distribution map of the species. This ant inhabits the Brazilian Atlantic forest, an ecosystem strongly impacted by fragmentation. The males show clear morphological differences from the known males of other species of Dinoponera. We briefly discuss the relevance of the male description for the conservation strategies of this ant.
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Closing remarks: A visit to Dr. Stout's and Dr. Murphy's forest health clinic
Russell T. Graham; Theresa B. Jain
1995-01-01
Two years ago I attended a camp with fellow silviculturists in central North Carolina. Camp Kanuga provided all kinds of fun activities. We described ecosystems and designed silvicultural systems for a variety of objectives; and as our camp scribe (Phil Aune) noted, the central camp theme evolved into ecosystem management. I am not sure exactly how or what happened but...
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Urban forest structure, ecosystem services and change in Syracuse, NY
David J. Nowak; Robert E. Hoehn; Allison R. Bodine; Eric J. Greenfield; Jarlath O' Neil-Dunne
2013-01-01
The tree population within the City of Syracuse was assessed using a random sampling of plots in 1999, 2001 and 2009 to determine how the population and the ecosystem services these trees provide have changed over time. Ecosystem services and values for carbon sequestration, air pollution removal and changes in building energy use were derived using the i-Tree Eco...
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T.N. Hollingsworth
2008-01-01
In this overview, I present extensive studies looking at the structure and function of the black spruce (Picea mariana) ecosystem of the boreal region of interior Alaska. One of the studies provides a classification of black spruce communities, the most abundant forest type in the region. Other studies examine large-scale processes that drive this...
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Understanding the Socioeconomic Effects of Wildfires on Western U.S. Public Lands
NASA Astrophysics Data System (ADS)
Sanchez, J. J.; Srivastava, L.; Marcos-Martinez, R.
2017-12-01
Climate change has resulted in the increased severity and frequency of forest disturbances due to wildfires, droughts, pests and diseases that compromise the sustainable provision of forest ecosystem services (e.g., water quantity and quality, carbon sequestration, recreation). A better understanding of the environmental and socioeconomic consequences of forest disturbances (i.e., wildfires) could improve the management and protection of public lands. We used a single-site benefit transfer function and spatially explicit information for demographic, socioeconomic, and site-specific characteristics to estimate the monetized value of market and non-market ecosystem services provided by forests on Western US public lands. These estimates are then used to approximate the costs of forest disturbances caused by wildfires of varying frequency and intensity, and across sites with heterogeneous characteristics and protection and management strategies. Our analysis provides credible estimates of the benefits of the forest for land management by the United States Forest Service, thereby assisting forest managers in planning resourcing and budgeting priorities.
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Rapid soil development after windthrow disturbance in pristine forests.
B.T. Bormann; H. Spaltenstein; M.H. McClellan; F.C. Ugolini; K. Cromack; S.M. Nay
1995-01-01
1. We examined how rapidly soils can change during secondary succession by observing soil development on 350-year chronosequences in three pristine forest ecosystems in south-east Alaska. 2. Soil surfaces, created by different windthrow events of known or estimated age, were examined within each of three forest stands (0.5-2.0 ha plots; i.e. a within-stand...
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Scott R. Abella
2008-01-01
Seed availability and leaf litter limit plant establishment in some ecosystems. To evaluate the hypothesis that these factors limit understory plant recruitment in Pinus ponderosa forests, I conducted a seeding and litter removal experiment at six thinned sites in the Fort Valley Experimental Forest, northern Arizona. Experimental seeding of four native species (...
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Scott R. Abella
2008-01-01
Seed availability and leaf litter limit plant establishment in some ecosystems. To evaluate the hypothesis that these factors limit understory plant recruitment in Pinus ponderosa forests, I conducted a seeding and litter removal experiment at six thinned sites in the Fort Valley Experimental Forest, northern Arizona. Experimental seeding of four native species (
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Disturbances catalyze the adaptation of forest ecosystems to changing climate conditions
Thom, Dominik; Rammer, Werner; Seidl, Rupert
2016-01-01
The rates of anthropogenic climate change substantially exceed those at which forest ecosystems – dominated by immobile, long-lived organisms – are able to adapt. The resulting maladaptation of forests has potentially detrimental effects on ecosystem functioning. Furthermore, as many forest-dwelling species are highly dependent on the prevailing tree species, a delayed response of the latter to a changing climate can contribute to an extinction debt and mask climate-induced biodiversity loss. However, climate change will likely also intensify forest disturbances. Here, we tested the hypothesis that disturbances foster the reorganization of ecosystems and catalyze the adaptation of forest composition to climate change. Our specific objectives were (i) to quantify the rate of autonomous forest adaptation to climate change, (ii) examine the role of disturbance in the adaptation process, and (iii) investigate spatial differences in climate-induced species turnover in an unmanaged mountain forest landscape (Kalkalpen National Park, Austria). Simulations with a process-based forest landscape model were performed for 36 unique combinations of climate and disturbance scenarios over 1000 years. We found that climate change strongly favored European beech and oak species (currently prevailing in mid- to low-elevation areas), with novel species associations emerging on the landscape. Yet, it took between 357 and 706 years before the landscape attained a dynamic equilibrium with the climate system. Disturbances generally catalyzed adaptation and decreased the time needed to attain equilibrium by up to 211 years. However, while increasing disturbance frequency and severity accelerated adaptation, increasing disturbance size had the opposite effect. Spatial analyses suggest that particularly the lowest and highest elevation areas will be hotspots of future species change. We conclude that the growing maladaptation of forests to climate and the long lead times of autonomous adaptation need to be considered more explicitly in the ongoing efforts to safeguard biodiversity and ecosystem services provisioning. PMID:27633953
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Disturbances catalyze the adaptation of forest ecosystems to changing climate conditions.
Thom, Dominik; Rammer, Werner; Seidl, Rupert
2017-01-01
The rates of anthropogenic climate change substantially exceed those at which forest ecosystems - dominated by immobile, long-lived organisms - are able to adapt. The resulting maladaptation of forests has potentially detrimental effects on ecosystem functioning. Furthermore, as many forest-dwelling species are highly dependent on the prevailing tree species, a delayed response of the latter to a changing climate can contribute to an extinction debt and mask climate-induced biodiversity loss. However, climate change will likely also intensify forest disturbances. Here, we tested the hypothesis that disturbances foster the reorganization of ecosystems and catalyze the adaptation of forest composition to climate change. Our specific objectives were (i) to quantify the rate of autonomous forest adaptation to climate change, (ii) examine the role of disturbance in the adaptation process, and (iii) investigate spatial differences in climate-induced species turnover in an unmanaged mountain forest landscape (Kalkalpen National Park, Austria). Simulations with a process-based forest landscape model were performed for 36 unique combinations of climate and disturbance scenarios over 1000 years. We found that climate change strongly favored European beech and oak species (currently prevailing in mid- to low-elevation areas), with novel species associations emerging on the landscape. Yet, it took between 357 and 706 years before the landscape attained a dynamic equilibrium with the climate system. Disturbances generally catalyzed adaptation and decreased the time needed to attain equilibrium by up to 211 years. However, while increasing disturbance frequency and severity accelerated adaptation, increasing disturbance size had the opposite effect. Spatial analyses suggest that particularly the lowest and highest elevation areas will be hotspots of future species change. We conclude that the growing maladaptation of forests to climate and the long lead times of autonomous adaptation need to be considered more explicitly in the ongoing efforts to safeguard biodiversity and ecosystem services provisioning. © 2016 John Wiley & Sons Ltd.
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NASA Astrophysics Data System (ADS)
Gobbi, José; Deguillon, Marie
2017-04-01
Payments for ecosystem services (PES) aim to improve the supply of ecosystem services (ES) by making payments to service providers, which are conditional on the provision of those services. Payments cannot be conditional unless the service can be effectively monitored. Direct monitoring of ES to assess conditionality could be methodologically complex and operatively expensive. To overcome such constraints, the pilot "GEF-PES Project" of Northern Argentina has developed a set of five indicators on forest conservation status (CS) as a basis for estimating the amount of ES provided -considering a positive correlation between the CS of a forest and its level of provision of ecosystem services -and for operationalizing the PES. Field data indicate that selected indicators: (i) exhibit strong correlation with the amount of carbon and biodiversity provided by forests according to their CS, ii) are cost-effective to monitor ES conditionality and (iii) allow easy application of payment levels.
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Seidl, Rupert; Aggestam, Filip; Rammer, Werner; Blennow, Kristina; Wolfslehner, Bernhard
2016-05-01
Climate vulnerability of managed forest ecosystems is not only determined by ecological processes but also influenced by the adaptive capacity of forest managers. To better understand adaptive behaviour, we conducted a questionnaire study among current and future forest managers (i.e. active managers and forestry students) in Austria. We found widespread belief in climate change (94.7 % of respondents), and no significant difference between current and future managers. Based on intended responses to climate-induced ecosystem changes, we distinguished four groups: highly sensitive managers (27.7 %), those mainly sensitive to changes in growth and regeneration processes (46.7 %), managers primarily sensitive to regeneration changes (11.2 %), and insensitive managers (14.4 %). Experiences and beliefs with regard to disturbance-related tree mortality were found to particularly influence a manager's sensitivity to climate change. Our findings underline the importance of the social dimension of climate change adaptation, and suggest potentially strong adaptive feedbacks between ecosystems and their managers.
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A New Approach to Extract Forest Water Use Efficiency from Eddy Covariance Data
NASA Astrophysics Data System (ADS)
Scanlon, T. M.; Sulman, B. N.
2016-12-01
Determination of forest water use efficiency (WUE) from eddy covariance data typically involves the following steps: (a) estimating gross primary productivity (GPP) from direct measurements of net ecosystem exchange (NEE) by extrapolating nighttime ecosystem respiration (ER) to daytime conditions, and (b) assuming direct evaporation (E) is minimal several days after rainfall, meaning that direct measurements of evapotranspiration (ET) are identical to transpiration (T). Both of these steps could lead to errors in the estimation of forest WUE. Here, we present a theoretical approach for estimating WUE through the analysis of standard eddy covariance data, which circumvents these steps. Only five statistics are needed from the high-frequency time series to extract WUE: CO2 flux, water vapor flux, standard deviation in CO2 concentration, standard deviation in water vapor concentration, and the correlation coefficient between CO2 and water vapor concentration for each half-hour period. The approach is based on the assumption that stomatal fluxes (i.e. photosynthesis and transpiration) lead to perfectly negative correlations and non-stomatal fluxes (i.e. ecosystem respiration and direct evaporation) lead to perfectly positive correlations within the CO2 and water vapor high frequency time series measured above forest canopies. A mathematical framework is presented, followed by a proof of concept using eddy covariance data and leaf-level measurements of WUE.
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NASA Technical Reports Server (NTRS)
Meng, Ran; Wu, Jin; Schwager, Kathy L.; Zhao, Feng; Dennison, Philip E.; Cook, Bruce D.; Brewster, Kristen; Green, Timothy M.; Serbin, Shawn P.
2017-01-01
As a primary disturbance agent, fire significantly influences local processes and services of forest ecosystems. Although a variety of remote sensing based approaches have been developed and applied to Landsat mission imagery to infer burn severity at 30 m spatial resolution, forest burn severity have still been seldom assessed at fine spatial scales (less than or equal to 5 m) from very-high-resolution (VHR) data. We assessed a 432 ha forest fire that occurred in April 2012 on Long Island, New York, within the Pine Barrens region, a unique but imperiled fire-dependent ecosystem in the northeastern United States. The mapping of forest burn severity was explored here at fine spatial scales, for the first time using remotely sensed spectral indices and a set of Multiple Endmember Spectral Mixture Analysis (MESMA) fraction images from bi-temporal - pre- and post-fire event - WorldView-2 (WV-2) imagery at 2 m spatial resolution. We first evaluated our approach using 1 m by 1 m validation points at the sub-crown scale per severity class (i.e. unburned, low, moderate, and high severity) from the post-fire 0.10 m color aerial ortho-photos; then, we validated the burn severity mapping of geo-referenced dominant tree crowns (crown scale) and 15 m by 15 m fixed-area plots (inter-crown scale) with the post-fire 0.10 m aerial ortho-photos and measured crown information of twenty forest inventory plots. Our approach can accurately assess forest burn severity at the sub-crown (overall accuracy is 84% with a Kappa value of 0.77), crown (overall accuracy is 82% with a Kappa value of 0.76), and inter-crown scales (89% of the variation in estimated burn severity ratings (i.e. Geo-Composite Burn Index (CBI)). This work highlights that forest burn severity mapping from VHR data can capture heterogeneous fire patterns at fine spatial scales over the large spatial extents. This is important since most ecological processes associated with fire effects vary at the less than 30 m scale and VHR approaches could significantly advance our ability to characterize fire effects on forest ecosystems.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Meng, Ran; Wu, Jin; Schwager, Kathy L.
As a primary disturbance agent, fire significantly influences local processes and services of forest ecosystems. Although a variety of remote sensing based approaches have been developed and applied to Landsat mission imagery to infer burn severity at 30 m spatial resolution, forest burn severity have still been seldom assessed at fine spatial scales (≤ 5 m) from very-high-resolution (VHR) data. Here we assessed a 432 ha forest fire that occurred in April 2012 on Long Island, New York, within the Pine Barrens region, a unique but imperiled fire-dependent ecosystem in the northeastern United States. The mapping of forest burn severitymore » was explored here at fine spatial scales, for the first time using remotely sensed spectral indices and a set of Multiple Endmember Spectral Mixture Analysis (MESMA) fraction images from bi-temporal — pre- and post-fire event — WorldView-2 (WV-2) imagery at 2 m spatial resolution. We first evaluated our approach using 1 m by 1 m validation points at the sub-crown scale per severity class (i.e. unburned, low, moderate, and high severity) from the post-fire 0.10 m color aerial ortho-photos; then, we validated the burn severity mapping of geo-referenced dominant tree crowns (crown scale) and 15 m by 15 m fixed-area plots (inter-crown scale) with the post-fire 0.10 m aerial ortho-photos and measured crown information of twenty forest inventory plots. Our approach can accurately assess forest burn severity at the sub-crown (overall accuracy is 84% with a Kappa value of 0.77), crown (overall accuracy is 82% with a Kappa value of 0.76), and inter-crown scales (89% of the variation in estimated burn severity ratings (i.e. Geo-Composite Burn Index (CBI)). Lastly, this work highlights that forest burn severity mapping from VHR data can capture heterogeneous fire patterns at fine spatial scales over the large spatial extents. This is important since most ecological processes associated with fire effects vary at the < 30 m scale and VHR approaches could significantly advance our ability to characterize fire effects on forest ecosystems.« less
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Meng, Ran; Wu, Jin; Schwager, Kathy L.; ...
2017-01-21
As a primary disturbance agent, fire significantly influences local processes and services of forest ecosystems. Although a variety of remote sensing based approaches have been developed and applied to Landsat mission imagery to infer burn severity at 30 m spatial resolution, forest burn severity have still been seldom assessed at fine spatial scales (≤ 5 m) from very-high-resolution (VHR) data. Here we assessed a 432 ha forest fire that occurred in April 2012 on Long Island, New York, within the Pine Barrens region, a unique but imperiled fire-dependent ecosystem in the northeastern United States. The mapping of forest burn severitymore » was explored here at fine spatial scales, for the first time using remotely sensed spectral indices and a set of Multiple Endmember Spectral Mixture Analysis (MESMA) fraction images from bi-temporal — pre- and post-fire event — WorldView-2 (WV-2) imagery at 2 m spatial resolution. We first evaluated our approach using 1 m by 1 m validation points at the sub-crown scale per severity class (i.e. unburned, low, moderate, and high severity) from the post-fire 0.10 m color aerial ortho-photos; then, we validated the burn severity mapping of geo-referenced dominant tree crowns (crown scale) and 15 m by 15 m fixed-area plots (inter-crown scale) with the post-fire 0.10 m aerial ortho-photos and measured crown information of twenty forest inventory plots. Our approach can accurately assess forest burn severity at the sub-crown (overall accuracy is 84% with a Kappa value of 0.77), crown (overall accuracy is 82% with a Kappa value of 0.76), and inter-crown scales (89% of the variation in estimated burn severity ratings (i.e. Geo-Composite Burn Index (CBI)). Lastly, this work highlights that forest burn severity mapping from VHR data can capture heterogeneous fire patterns at fine spatial scales over the large spatial extents. This is important since most ecological processes associated with fire effects vary at the < 30 m scale and VHR approaches could significantly advance our ability to characterize fire effects on forest ecosystems.« less
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Dynamics of Ecosystem Services during Forest Transitions in Reventazón, Costa Rica.
Vallet, Améline; Locatelli, Bruno; Levrel, Harold; Brenes Pérez, Christian; Imbach, Pablo; Estrada Carmona, Natalia; Manlay, Raphaël; Oszwald, Johan
2016-01-01
The forest transition framework describes the temporal changes of forest areas with economic development. A first phase of forest contraction is followed by a second phase of expansion once a turning point is reached. This framework does not differentiate forest types or ecosystem services, and describes forests regardless of their contribution to human well-being. For several decades, deforestation in many tropical regions has degraded ecosystem services, such as watershed regulation, while increasing provisioning services from agriculture, for example, food. Forest transitions and expansion have been observed in some countries, but their consequences for ecosystem services are often unclear. We analyzed the implications of forest cover change on ecosystem services in Costa Rica, where a forest transition has been suggested. A review of literature and secondary data on forest and ecosystem services in Costa Rica indicated that forest transition might have led to an ecosystem services transition. We modeled and mapped the changes of selected ecosystem services in the upper part of the Reventazón watershed and analyzed how supply changed over time in order to identify possible transitions in ecosystem services. The modeled changes of ecosystem services is similar to the second phase of a forest transition but no turning point was identified, probably because of the limited temporal scope of the analysis. Trends of provisioning and regulating services and their tradeoffs were opposite in different spatial subunits of our study area, which highlights the importance of scale in the analysis of ecosystem services and forest transitions. The ecosystem services transition framework proposed in this study is useful for analyzing the temporal changes of ecosystem services and linking socio-economic drivers to ecosystem services demand at different scales.
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Dynamics of Ecosystem Services during Forest Transitions in Reventazón, Costa Rica
Vallet, Améline; Locatelli, Bruno; Levrel, Harold; Brenes Pérez, Christian; Imbach, Pablo; Estrada Carmona, Natalia; Manlay, Raphaël; Oszwald, Johan
2016-01-01
The forest transition framework describes the temporal changes of forest areas with economic development. A first phase of forest contraction is followed by a second phase of expansion once a turning point is reached. This framework does not differentiate forest types or ecosystem services, and describes forests regardless of their contribution to human well-being. For several decades, deforestation in many tropical regions has degraded ecosystem services, such as watershed regulation, while increasing provisioning services from agriculture, for example, food. Forest transitions and expansion have been observed in some countries, but their consequences for ecosystem services are often unclear. We analyzed the implications of forest cover change on ecosystem services in Costa Rica, where a forest transition has been suggested. A review of literature and secondary data on forest and ecosystem services in Costa Rica indicated that forest transition might have led to an ecosystem services transition. We modeled and mapped the changes of selected ecosystem services in the upper part of the Reventazón watershed and analyzed how supply changed over time in order to identify possible transitions in ecosystem services. The modeled changes of ecosystem services is similar to the second phase of a forest transition but no turning point was identified, probably because of the limited temporal scope of the analysis. Trends of provisioning and regulating services and their tradeoffs were opposite in different spatial subunits of our study area, which highlights the importance of scale in the analysis of ecosystem services and forest transitions. The ecosystem services transition framework proposed in this study is useful for analyzing the temporal changes of ecosystem services and linking socio-economic drivers to ecosystem services demand at different scales. PMID:27390869
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NASA Astrophysics Data System (ADS)
Giambelluca, T. W.; Mudd, R. G.; Huang, M.; Nullet, M.; Asner, G. P.; Martin, R.; Ostertag, R.; Miyazawa, Y.; Litton, C. M.
2016-12-01
Uncertainty about the local and regional effects of global climate warming on terrestrial ecosystems and their ability to produce ecosystem goods and services is a serious constraint for land-based natural resource managers. In Hawai`i and other Pacific Islands, this issue is complicated by the presence of numerous and widespread non-native invasive species, including invasive trees. As warming continues and other climate variables change in response to temperature increases, how will native- and non-native-dominated ecosystems respond? To address this question, eddy covariance flux towers were established and operated for approximately a decade over native forest and at a site invaded by a non-native tree. Flux data were analyzed to determine the sensitivity of carbon exchange rates to fluctuations in ambient CO2 concentration, temperature (T), humidity, photosynthetically active radiation (PAR), and soil moisture (SM). At both sites, gross primary production (GPP) is strongly controlled by PAR and to a lesser extent by T. Ecosystem respiration (Re) responds to T and SM at both sites, as expected. Net ecosystem carbon exchange (NEE) is predominantly controlled by PAR at both sites. Higher temperature is associated with higher rates of photosynthesis and greater Re, thereby canceling the net effect of temperature on carbon exchange. Hence, no significant effect of temperature on NEE was found at either site. These results suggest that the direct effects of future warming will be small in relation to the effects of any changes in cloud cover that affect incident solar radiation. Cloud cover in Hawai`i could be affected by projected increases in atmospheric stability (reduced cloud cover) and increases in humidity (increased cloud cover). Light response (GPP sensitivity to PAR) was found to be significantly greater at the non-native site, suggesting that a future decrease in cloud cover would favor the non-native ecosystem, while increased cloudiness would cause a greater reduction in carbon uptake in the non-native forest.
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NASA Astrophysics Data System (ADS)
Litton, C. M.; Laursen, S. C.; Phifer, C.; Giardina, C. P.
2012-12-01
Plant phenology is a powerful indicator of how climate change affects native ecosystems, and also provides an experiential outdoor learning opportunity for promoting youth conservation education and awareness. We developed a youth conservation education curriculum, including both classroom and field components, for local middle and high school students from Hawaii. The curriculum is focused on linking plant phenology and climate change, with emphasis on ecologically and culturally important native trees and birds at Hakalau Forest National Wildlife Refuge (NWR), on the Island of Hawaii. In this curriculum, students: (i) visit Hakalau Forest NWR to learn about the ecology of native ecosystems, including natural disturbance regimes and the general concept of change in forest ecosystems; (ii) learn about human-induced climate change and its potential impact on native species; and (iii) collect plant phenology measurements and publish these data on the USA National Phenology Network website. This youth conservation education curriculum represents a close collaboration between Hakalau Forest NWR; the Friends of Hakalau Forest NWR; the College of Tropical Agriculture and Human Resources at the University of Hawaii at Manoa; the USDA Forest Service; and Imi Pono no Ka Aina, an environmental education and outreach program for the Three Mountain Alliance Watershed Partnership. In the Winter and Spring of 2011-2012, we developed classroom and field portions of the curriculum. In the Spring and Summer of 2012, we recruited four groups of participants, with a total of ~40 students, who visited the refuge to participate in the curriculum. Preliminary phenology observations based upon ~4 months of measurements show low to medium levels of flowering, fruiting and leaf flush. However, the real science value of this program will come over years to decades of accumulated student activity. From this, we anticipate the emergence of a unique tropical montane forest dataset on plant phenology for Hakalau Forest NWR. This work would not otherwise exist in Hawaii as we are the first and only site in Hawaii participating in the USA National Phenology Network. In turn, the education and outreach value of this program is immediate, as participating students are exposed to: (i) native ecosystems that they would never otherwise have the opportunity to visit; (ii) the concept of plant phenology and its utility for monitoring native ecosystems; and (iii) the concept of change, including anthropogenic climate change. The curriculum we have developed in Hawaii can be easily replicated elsewhere by: (i) selecting local species with high cultural and ecological value; (ii) devising phenology collection methods tailored to these local species, and student backgrounds and educational levels; and (iii) building sustainable partnerships between community conservation groups and government agencies.
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Forest aging, disturbance and the carbon cycle.
Curtis, Peter S; Gough, Christopher M
2018-05-16
Contents Summary I. Introduction II. Forest aging and carbon storage III. Successional trends of NEP in northern deciduous forests IV. Mechanisms sustaining NEP in aging deciduous forests Acknowledgements References SUMMARY: Large areas of forestland in temperate North America, as well as in other parts of the world, are growing older and will soon transition into middle and then late successional stages exceeding 100 yr in age. These ecosystems have been important regional carbon sinks as they recovered from prior anthropogenic and natural disturbance, but their future sink strength, or annual rate of carbon storage, is in question. Ecosystem development theory predicts a steady decline in annual carbon storage as forests age, but newly available, direct measurements of forest net CO 2 exchange challenge that prediction. In temperate deciduous forests, where moderate severity disturbance regimes now often prevail, there is little evidence for any marked decline in carbon storage rate during mid-succession. Rather, an increase in physical and biological complexity under these disturbance regimes may drive increases in resource-use efficiency and resource availability that help to maintain significant carbon storage in these forests well past the century mark. Conservation of aging deciduous forests may therefore sustain the terrestrial carbon sink, whilst providing other goods and services afforded by these biologically and structurally complex ecosystems. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.
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Ecosystem processes and nitrogen export in northern U.S. watersheds.
Stottlemyer, R.
2001-01-01
There is much interest in the relationship of atmospheric nitrogen (N) inputs to ecosystem outputs as an indicator of possible "nitrogen saturation" by human activity. Longer-term, ecosystem-level mass balance studies suggest that the relationship is not clear and that other ecosystem processes may dominate variation in N outputs. We have been studying small, forested watershed ecosystems in five northern watersheds for periods up to 35 years. Here I summarize the research on ecosystem processes and the N budget. During the past 2 decades, average wet-precipitation N inputs ranged from about 0.1 to 6 kg N ha(-1) year(-1) among sites. In general, sites with the lowest N inputs had the highest output-to-input ratios. In the Alaska watersheds, streamwater N output exceeded inputs by 70 to 250%. The ratio of mean monthly headwater nitrate (NO3-) concentration to precipitation NO3- concentration declined with increased precipitation concentration. A series of ecosystem processes have been studied and related to N outputs. The most important appear to be seasonal change in hydrologic flowpath, soil freezing, seasonal forest-floor inorganic N pools resulting from over-winter mineralization beneath the snowpack, spatial variation in watershed forest-floor inorganic N pools, the degree to which snowmelt percolates soils, and gross soil N mineralization rates.
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Balancing trade-offs between ecosystem services in Germany’s forests under climate change
NASA Astrophysics Data System (ADS)
Gutsch, Martin; Lasch-Born, Petra; Kollas, Chris; Suckow, Felicitas; Reyer, Christopher P. O.
2018-04-01
Germany’s forests provide a variety of ecosystem services. Sustainable forest management aims to optimize the provision of these services at regional level. However, climate change will impact forest ecosystems and subsequently ecosystem services. The objective of this study is to quantify the effects of two alternative management scenarios and climate impacts on forest variables indicative of ecosystem services related to timber, habitat, water, and carbon. The ecosystem services are represented through nine model output variables (timber harvest, above and belowground biomass, net ecosystem production, soil carbon, percolation, nitrogen leaching, deadwood, tree dimension, broadleaf tree proportion) from the process-based forest model 4C. We simulated forest growth, carbon and water cycling until 2045 with 4C set-up for the whole German forest area based on National Forest Inventory data and driven by three management strategies (nature protection, biomass production and a baseline management) and an ensemble of regional climate scenarios (RCP2.6, RCP 4.5, RCP 8.5). We provide results as relative changes compared to the baseline management and observed climate. Forest management measures have the strongest effects on ecosystem services inducing positive or negative changes of up to 40% depending on the ecosystem service in question, whereas climate change only slightly alters ecosystem services averaged over the whole forest area. The ecosystem services ‘carbon’ and ‘timber’ benefit from climate change, while ‘water’ and ‘habitat’ lose. We detect clear trade-offs between ‘timber’ and all other ecosystem services, as well as synergies between ‘habitat’ and ‘carbon’. When evaluating all ecosystem services simultaneously, our results reveal certain interrelations between climate and management scenarios. North-eastern and western forest regions are more suitable to provide timber (while minimizing the negative impacts on remaining ecosystem services) whereas southern and central forest regions are more suitable to fulfil ‘habitat’ and ‘carbon’ services. The results provide the base for future forest management optimizations at the regional scale in order to maximize ecosystem services and forest ecosystem sustainability at the national scale.
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An ecosystem management strategy for Sierran mixed-conifer forests
Malcolm North; Peter Stine; Kevin O' Hara; William Zielinski; Scott Stephens
2009-01-01
Current Sierra Nevada forest management is often focused on strategically reducing fuels without an explicit strategy for ecological restoration across the landscape matrix. Summarizing recent scientific literature, we suggest managers produce different stand structures and densities across the landscape using topographic variables (i.e., slope shape, aspect, and slope...
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Returning fire to Ozark Highland forest ecosystems: Effects on advance regeneration
Daniel C. Dey; George Hartman
2005-01-01
In mature forests of the Ozark Highlands, MO, USA, we evaluated fire effects on the survival and growth of tree seedlings and saplings (i.e., advance regeneration), and used this information to develop species-specific models that predict the probability of survival based on initial tree size and number of times burned. A 1000 ha forest area was divided into five units...
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Incorporating threat in hotspots and coldspots of biodiversity and ecosystem services.
Schröter, Matthias; Kraemer, Roland; Ceauşu, Silvia; Rusch, Graciela M
2017-11-01
Spatial prioritization could help target conservation actions directed to maintain both biodiversity and ecosystem services. We delineate hotspots and coldspots of two biodiversity conservation features and five regulating and cultural services by incorporating an indicator of 'threat', i.e. timber harvest profitability for forest areas in Telemark (Norway). We found hotspots, where high values of biodiversity, ecosystem services and threat coincide, ranging from 0.1 to 7.1% of the area, depending on varying threshold levels. Targeting of these areas for conservation follows reactive conservation approaches. In coldspots, high biodiversity and ecosystem service values coincide with low levels of threat, and cover 0.1-3.4% of the forest area. These areas might serve proactive conservation approaches at lower opportunity cost (foregone timber harvest profits). We conclude that a combination of indicators of biodiversity, ecosystem services and potential threat is an appropriate approach for spatial prioritization of proactive and reactive conservation strategies.
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Loranty, Michael M; Berner, Logan T; Taber, Eric D; Kropp, Heather; Natali, Susan M; Alexander, Heather D; Davydov, Sergey P; Zimov, Nikita S
2018-01-01
Arctic ecosystems are characterized by a broad range of plant functional types that are highly heterogeneous at small (~1-2 m) spatial scales. Climatic changes can impact vegetation distribution directly, and also indirectly via impacts on disturbance regimes. Consequent changes in vegetation structure and function have implications for surface energy dynamics that may alter permafrost thermal dynamics, and are therefore of interest in the context of permafrost related climate feedbacks. In this study we examine small-scale heterogeneity in soil thermal properties and ecosystem carbon and water fluxes associated with varying understory vegetation in open-canopy larch forests in northeastern Siberia. We found that lichen mats comprise 16% of understory vegetation cover on average in open canopy larch forests, and lichen abundance was inversely related to canopy cover. Relative to adjacent areas dominated by shrubs and moss, lichen mats had 2-3 times deeper permafrost thaw depths and surface soils warmer by 1-2°C in summer and less than 1°C in autumn. Despite deeper thaw depths, ecosystem respiration did not differ across vegetation types, indicating that autotrophic respiration likely dominates areas with shrubs and moss. Summertime net ecosystem exchange of CO2 was negative (i.e. net uptake) in areas with high shrub cover, while positive (i.e. net loss) in lichen mats and areas with less shrub cover. Our results highlight relationships between vegetation and soil thermal dynamics in permafrost ecosystems, and underscore the necessity of considering both vegetation and permafrost dynamics in shaping carbon cycling in permafrost ecosystems.
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Forecasting Urban Forest Ecosystem Structure, Function, and Vulnerability
NASA Astrophysics Data System (ADS)
Steenberg, James W. N.; Millward, Andrew A.; Nowak, David J.; Robinson, Pamela J.; Ellis, Alexis
2017-03-01
The benefits derived from urban forest ecosystems are garnering increasing attention in ecological research and municipal planning. However, because of their location in heterogeneous and highly-altered urban landscapes, urban forests are vulnerable and commonly suffer disproportionate and varying levels of stress and disturbance. The objective of this study is to assess and analyze the spatial and temporal changes, and potential vulnerability, of the urban forest resource in Toronto, Canada. This research was conducted using a spatially-explicit, indicator-based assessment of vulnerability and i-Tree Forecast modeling of temporal changes in forest structure and function. Nine scenarios were simulated for 45 years and model output was analyzed at the ecosystem and municipal scale. Substantial mismatches in ecological processes between spatial scales were found, which can translate into unanticipated loss of function and social inequities if not accounted for in planning and management. At the municipal scale, the effects of Asian longhorned beetle and ice storm disturbance were far less influential on structure and function than changes in management actions. The strategic goals of removing invasive species and increasing tree planting resulted in a decline in carbon storage and leaf biomass. Introducing vulnerability parameters in the modeling increased the spatial heterogeneity in structure and function while expanding the disparities of resident access to ecosystem services. There was often a variable and uncertain relationship between vulnerability and ecosystem structure and function. Vulnerability assessment and analysis can provide strategic planning initiatives with valuable insight into the processes of structural and functional change resulting from management intervention.
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Forecasting Urban Forest Ecosystem Structure, Function, and Vulnerability.
Steenberg, James W N; Millward, Andrew A; Nowak, David J; Robinson, Pamela J; Ellis, Alexis
2017-03-01
The benefits derived from urban forest ecosystems are garnering increasing attention in ecological research and municipal planning. However, because of their location in heterogeneous and highly-altered urban landscapes, urban forests are vulnerable and commonly suffer disproportionate and varying levels of stress and disturbance. The objective of this study is to assess and analyze the spatial and temporal changes, and potential vulnerability, of the urban forest resource in Toronto, Canada. This research was conducted using a spatially-explicit, indicator-based assessment of vulnerability and i-Tree Forecast modeling of temporal changes in forest structure and function. Nine scenarios were simulated for 45 years and model output was analyzed at the ecosystem and municipal scale. Substantial mismatches in ecological processes between spatial scales were found, which can translate into unanticipated loss of function and social inequities if not accounted for in planning and management. At the municipal scale, the effects of Asian longhorned beetle and ice storm disturbance were far less influential on structure and function than changes in management actions. The strategic goals of removing invasive species and increasing tree planting resulted in a decline in carbon storage and leaf biomass. Introducing vulnerability parameters in the modeling increased the spatial heterogeneity in structure and function while expanding the disparities of resident access to ecosystem services. There was often a variable and uncertain relationship between vulnerability and ecosystem structure and function. Vulnerability assessment and analysis can provide strategic planning initiatives with valuable insight into the processes of structural and functional change resulting from management intervention.
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Wastewater Applications in Forest Ecosystems,
1982-08-01
profiles of various vegetative canopies ................ 5 4. Nitrate-N concentration in soil solution collected at 180 cm under three different...I .,-I --- ’I’ ’’ I’ ~Poplar Seedling 30- 20. 1974 1975 1976 1977 1978 Figure 4. Nitrate-N concentration in soil solution collected at 180 cm
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Vulnerability of tropical forest ecosystems and forest dependent communities to droughts.
Vogt, D J; Vogt, K A; Gmur, S J; Scullion, J J; Suntana, A S; Daryanto, S; Sigurðardóttir, R
2016-01-01
Energy captured by and flowing through a forest ecosystem can be indexed by its total Net Primary Productivity (NPP). This forest NPP can also be a reflection of its sensitivity to, and its ability to adapt to, any climate change while also being harvested by humans. However detecting and identifying the vulnerability of forest and human ecosystems to climate change requires information on whether these coupled social and ecological systems are able to maintain functionality while responding to environmental variability. To better understand what parameters might be representative of environmental variability, we compiled a metadata analysis of 96 tropical forest sites. We found that three soil textural classes (i.e., sand, sandy loam and clay) had significant but different relationships between NPP and precipitation levels. Therefore, assessing the vulnerability of forests and forest dependent communities to drought was carried out using data from those sites that had one of those three soil textural classes. For example, forests growing on soil textures of sand and clay had NPP levels decreasing as precipitation levels increased, in contrast to those forest sites that had sandy loam soils where NPP levels increased. Also, forests growing on sandy loam soil textures appeared better adapted to grow at lower precipitation levels compared to the sand and clay textured soils. In fact in our tropical database the lowest precipitation level found for the sandy loam soils was 821 mm yr(-1) compared to sand at 1739 mm yr(-1) and clay at 1771 mm yr(-1). Soil texture also determined the level of NPP reached by a forest, i.e., forest growing on sandy loam and clay reached low-medium NPP levels while higher NPP levels (i.e., medium, high) were found on sand-textured soils. Intermediate precipitation levels (>1800-3000 mm yr(-1)) were needed to grow forests at the medium and high NPP levels. Low thresholds of NPP were identified at both low (∼750 mm) and high precipitation (>3500 mm) levels. By combining data on the ratios of precipitation to the amount of biomass produced in a year with how much less precipitation input occurs during a drought year, it is possible to estimate whether productivity levels are sufficient to support forest growth and forest dependent communities following a drought. In this study, the ratios of annual precipitation inputs required to produce 1 Mg ha(-1) yr(-1) biomass by soil texture class varied across the three soil textural classes. By using a conservative estimate of 20% of productivity collected or harvested by people and 30% precipitation reduction level as triggering a drought, it was possible to estimate a potential loss of annual productivity due to a drought. In this study, the total NPP unavailable due to drought and harvest by forest dependent communities per year was 10.2 Mg ha(-1) yr(-1) for the sandy textured soils (64% of NPP still available), 8.4 Mg ha(-1) yr(-1) for the sandy loam textured soils (60% available) and 12.7 Mg ha(-1) yr(-1) for the clay textured soils (29% available). Forests growing on clay textured soils would be most vulnerable to drought triggered reductions in productivity so NPP levels would be inadequate to maintain ecosystem functions and would potentially cause a forest-to-savanna shift. Further, these forests would not be able to provide sufficient NPP to satisfy the requirements of forest dependent communities. By predicting the productivity responses of different tropical forest ecosystems to changes in precipitation patterns coupled with edaphic data, it could be possible to spatially identify where tropical forests are most vulnerable to climate change impacts and where mitigation efforts should be concentrated. Copyright © 2015 Elsevier Inc. All rights reserved.
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Sustainable carbon uptake - important ecosystem service within sustainable forest management
NASA Astrophysics Data System (ADS)
Zorana Ostrogović Sever, Maša; Anić, Mislav; Paladinić, Elvis; Alberti, Giorgio; Marjanović, Hrvoje
2016-04-01
Even-aged forest management with natural regeneration under continuous cover (i.e. close to nature management) is considered to be sustainable regarding the yield, biodiversity and stability of forest ecosystems. Recently, in the context of climate change, there is a raising question of sustainable forest management regarding carbon uptake. Aim of this research was to explore whether current close to nature forest management approach in Croatia can be considered sustainable in terms of carbon uptake throughout the life-time of Pedunculate oak forest. In state-owned managed forest a chronosequence experiment was set up and carbon stocks in main ecosystem pools (live biomass, dead wood, litter and mineral soil layer), main carbon fluxes (net primary production, soil respiration (SR), decomposition) and net ecosystem productivity were estimated in eight stands of different age (5, 13, 38, 53, 68, 108, 138 and 168 years) based on field measurements and published data. Air and soil temperature and soil moisture were recorded on 7 automatic mini-meteorological stations and weekly SR measurements were used to parameterize SR model. Carbon balance was estimated at weekly scale for the growing season 2011 (there was no harvesting), as well as throughout the normal rotation period of 140 years (harvesting was included). Carbon stocks in different ecosystem pools change during a stand development. Carbon stocks in forest floor increase with stand age, while carbon stocks in dead wood are highest in young and older stands, and lowest in middle-aged, mature stands. Carbon stocks in mineral soil layer were found to be stable across chronosequence with no statistically significant age-dependent trend. Pedunculate Oak stand, assuming successful regeneration, becomes carbon sink very early in a development phase, between the age of 5 and 13 years, and remains carbon sink even after the age of 160 years. Greatest carbon sink was reached in the stand aged 53 years. Obtained results indicate that current harvesting practice has no detrimental effect on carbon stored in forest soil. Observed early and long-lasting carbon sink suggest that close to nature forest management can be considered sustainable in terms of carbon uptake. Also, observed carbon sink in the oldest stand is valuable information for potential debate on prolonging rotation period in this type of forest ecosystems.
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Sheng, Wenping; Yu, Guirui; Fang, Huajun; Jiang, Chunming; Yan, Junhua; Zhou, Mei
2014-01-01
We added the stable isotope 15N in the form of (15NH4)2SO4 and K15NO3 to forest ecosystems in eastern China under two different N deposition levels to study the fate of the different forms of deposited N. Prior to the addition of the 15N tracers, the natural 15N abundance ranging from −3.4‰ to +10.9‰ in the forest under heavy N deposition at Dinghushan (DHS), and from −3.92‰ to +7.25‰ in the forest under light N deposition at Daxinganling (DXAL). Four months after the tracer application, the total 15N recovery from the major ecosystem compartments ranged from 55.3% to 90.5%. The total 15N recoveries were similar under the (15NH4)2SO4 tracer treatment in both two forest ecosystems, whereas the total 15N recovery was significantly lower in the subtropical forest ecosystem at DHS than in the boreal forest ecosystem at DXAL under the K15NO3 tracer treatment. The 15N assimilated into the tree biomass represented only 8.8% to 33.7% of the 15N added to the forest ecosystems. In both of the tracer application treatments, more 15N was recovered from the tree biomass in the subtropical forest ecosystem at DHS than the boreal forest ecosystem at DXAL. The amount of 15N assimilated into tree biomass was greater under the K15NO3 tracer treatment than that of the (15NH4)2SO4 treatment in both forest ecosystems. This study suggests that, although less N was immobilized in the forest ecosystems under more intensive N deposition conditions, forest ecosystems in China strongly retain N deposition, even in areas under heavy N deposition intensity or in ecosystems undergoing spring freezing and thawing melts. Compared to ammonium deposition, deposited nitrate is released from the forest ecosystem more easily. However, nitrate deposition could be retained mostly in the plant N pool, which might lead to more C sequestration in these ecosystems. PMID:24586688
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Sheng, Wenping; Yu, Guirui; Fang, Huajun; Jiang, Chunming; Yan, Junhua; Zhou, Mei
2014-01-01
We added the stable isotope (15)N in the form of ((15)NH4)2SO4 and K(15)NO3 to forest ecosystems in eastern China under two different N deposition levels to study the fate of the different forms of deposited N. Prior to the addition of the (15)N tracers, the natural (15)N abundance ranging from -3.4‰ to +10.9‰ in the forest under heavy N deposition at Dinghushan (DHS), and from -3.92‰ to +7.25‰ in the forest under light N deposition at Daxinganling (DXAL). Four months after the tracer application, the total (15)N recovery from the major ecosystem compartments ranged from 55.3% to 90.5%. The total (15)N recoveries were similar under the ((15)NH4)2SO4 tracer treatment in both two forest ecosystems, whereas the total (15)N recovery was significantly lower in the subtropical forest ecosystem at DHS than in the boreal forest ecosystem at DXAL under the K(15)NO3 tracer treatment. The (15)N assimilated into the tree biomass represented only 8.8% to 33.7% of the (15)N added to the forest ecosystems. In both of the tracer application treatments, more (15)N was recovered from the tree biomass in the subtropical forest ecosystem at DHS than the boreal forest ecosystem at DXAL. The amount of (15)N assimilated into tree biomass was greater under the K(15)NO3 tracer treatment than that of the ((15)NH4)2SO4 treatment in both forest ecosystems. This study suggests that, although less N was immobilized in the forest ecosystems under more intensive N deposition conditions, forest ecosystems in China strongly retain N deposition, even in areas under heavy N deposition intensity or in ecosystems undergoing spring freezing and thawing melts. Compared to ammonium deposition, deposited nitrate is released from the forest ecosystem more easily. However, nitrate deposition could be retained mostly in the plant N pool, which might lead to more C sequestration in these ecosystems.
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NASA Astrophysics Data System (ADS)
Xu, Y.; Huang, M.; Keller, M. M.; Longo, M.; Knox, R. G.; Koven, C.; Fisher, R.
2016-12-01
As a key component in the climate system, old-growth tropical forests act as carbon sinks that remove CO2 from the atmosphere. However, these forests could be easily turned into C sources when disturbed. In fact, over half of tropical forests have been cleared or logged, and almost half of standing primary tropical forests are designated for timber production. Existing literature suggests that timber harvests alone could contribute up to 25% as much C losses as deforestation in Amazon. Yet, the spatial extent and recovery trajectory of disturbed forests in a changing climate are highly uncertain. This study constitutes our first attempt to quantify impacts of selective logging on water, energy, and carbon budgets in Amazon forests using the Functionally Assembled Terrestrial Ecosystem Simulator (FATES). The Community Land Model version 4.5 (CLM4.5), with and without FATES turned on, are configured to run at two flux towers established in the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA). One tower is located at in an old-growth forest (i.e. KM67) and the other is located in a selectively logged site (i.e., KM83). The three CLM4.5 options, (1) Satellite Phenology (CLM4.5-SP), (2) Century-based biogeochemical cycling with prognostic phenology (CLM4.5-BGC), and (3) CLM4.5-FATES, are spun up to equilibrium by recycling the observed meteorology at the towers, respectively. The simulated fluxes (i.e., sensible heat, latent heat, and net ecosystem exchange) are then compared to observations at KM67 to evaluate the capability of the models in capturing water and carbon dynamics in old-growth tropical forests. Our results suggest that all three models perform reasonably well in capturing the fluxes but demographic features simulated by FATES, such as distributions of diameter at breast height (DBH) and stem density (SD), are skewed heavily toward extremely large trees (e.g., > 100 cm in DBH) when compared to site surveys at the forest plots. Efforts are underway to evaluate parametric sensitivity in FATES to improve simulations in old-growth forests, and to implement parameterization to represent pulse disturbance to carbon pools created by logging events at different intensities, and follow-up recovery closely related to gap-phase regeneration and competition for lights within the gaps.
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NASA Astrophysics Data System (ADS)
Henrot, Alexandra-Jane; François, Louis; Dury, Marie; Hambuckers, Alain; Jacquemin, Ingrid; Minet, Julien; Tychon, Bernard; Heinesch, Bernard; Horemans, Joanna; Deckmyn, Gaby
2015-04-01
Eddy covariance measurements are an essential resource to understand how ecosystem carbon fluxes react in response to climate change, and to help to evaluate and validate the performance of land surface and vegetation models at regional and global scale. In the framework of the MASC project (« Modelling and Assessing Surface Change impacts on Belgian and Western European climate »), vegetation dynamics and carbon fluxes of forest and grassland ecosystems simulated by the CARAIB dynamic vegetation model (Dury et al., iForest - Biogeosciences and Forestry, 4:82-99, 2011) are evaluated and validated by comparison of the model predictions with eddy covariance data. Here carbon fluxes (e.g. net ecosystem exchange (NEE), gross primary productivity (GPP), and ecosystem respiration (RECO)) and evapotranspiration (ET) simulated with the CARAIB model are compared with the fluxes measured at several eddy covariance flux tower sites in Belgium and Western Europe, chosen from the FLUXNET global network (http://fluxnet.ornl.gov/). CARAIB is forced either with surface atmospheric variables derived from the global CRU climatology, or with in situ meteorological data. Several tree (e.g. Pinus sylvestris, Fagus sylvatica, Picea abies) and grass species (e.g. Poaceae, Asteraceae) are simulated, depending on the species encountered on the studied sites. The aim of our work is to assess the model ability to reproduce the daily, seasonal and interannual variablility of carbon fluxes and the carbon dynamics of forest and grassland ecosystems in Belgium and Western Europe.
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Longleaf Pine Ecosystem Restoration on Small and Mid-Sized Tracts
Joan L. Walker
1999-01-01
Speaking of restoring the longleaf pine ecosystem, conservationists may present images of open stands I trees, prescribed burning, grassy ground layers, and of providing habitat for red-cockaded woodpeckers. Unfortunately, planting a longleaf pine forest, using fire, and recovering an endangered woodpecker all seem require lands larger than a backyard. To many,...
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Sudhakar Reddy, C; Vazeed Pasha, S; Jha, C S; Dadhwal, V K
2015-07-01
Conservation of biodiversity has been put to the highest priority throughout the world. The process of identifying threatened ecosystems will search for different drivers related to biodiversity loss. The present study aimed to generate spatial information on deforestation and ecological degradation indicators of fragmentation and forest fires using systematic conceptual approach in Telangana state, India. Identification of ecosystems facing increasing vulnerability can help to safeguard the extinctions of species and useful for conservation planning. The technological advancement of satellite remote sensing and Geographical Information System has increased greatly in assessment and monitoring of ecosystem-level changes. The areas of threat were identified by creating grid cells (5 × 5 km) in Geographical Information System (GIS). Deforestation was assessed using multi-source data of 1930, 1960, 1975, 1985, 1995, 2005 and 2013. The forest cover of 40,746 km(2), 29,299 km(2), 18,652 km(2), 18,368 km(2), 18,006 km(2), 17,556 km(2) and 17,520 km(2) was estimated during 1930, 1960, 1975, 1985, 1995, 2005 and 2013, respectively. Historical evaluation of deforestation revealed that major changes had occurred in forests of Telangana and identified 1095 extinct, 397 critically endangered, 523 endangered and 311 vulnerable ecosystem grid cells. The fragmentation analysis has identified 307 ecosystem grid cells under critically endangered status. Forest burnt area information was extracted using AWiFS data of 2005 to 2014. Spatial analysis indicates total fire-affected forest in Telangana as 58.9% in a decadal period. Conservation status has been recorded depending upon values of threat for each grid, which forms the basis for conservation priority hotspots. Of existing forest, 2.1% grids had severe ecosystem collapse and had been included under the category of conservation priority hotspot-I, followed by 27.2% in conservation priority hotspot-II and 51.5% in conservation priority hotspot-III. This analysis complements assessment of ecosystems undergoing multiple threats. An integrated approach involving the deforestation and degradation indicators is useful in formulating the strategies to take appropriate conservation measures.
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Salas-Lopez, Alex; Mickal, Houadria; Menzel, Florian; Orivel, Jérôme
2017-01-01
The diversity and functional identity of organisms are known to be relevant to the maintenance of ecosystem processes but can be variable in different environments. Particularly, it is uncertain whether ecosystem processes are driven by complementary effects or by dominant groups of species. We investigated how community structure (i.e., the diversity and relative abundance of biological entities) explains the community-level contribution of Neotropical ant communities to different ecosystem processes in different environments. Ants were attracted with food resources representing six ant-mediated ecosystem processes in four environments: ground and vegetation strata in cropland and forest habitats. The exploitation frequencies of the baits were used to calculate the taxonomic and trophic structures of ant communities and their contribution to ecosystem processes considered individually or in combination (i.e., multifunctionality). We then investigated whether community structure variables could predict ecosystem processes and whether such relationships were affected by the environment. We found that forests presented a greater biodiversity and trophic complementarity and lower dominance than croplands, but this did not affect ecosystem processes. In contrast, trophic complementarity was greater on the ground than on vegetation and was followed by greater resource exploitation levels. Although ant participation in ecosystem processes can be predicted by means of trophic-based indices, we found that variations in community structure and performance in ecosystem processes were best explained by environment. We conclude that determining the extent to which the dominance and complementarity of communities affect ecosystem processes in different environments requires a better understanding of resource availability to different species.
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NASA Astrophysics Data System (ADS)
Mori, K.; Tada, K.; Tawara, Y.; Tosaka, H.; Ohno, K.; Asami, M.; Kosaka, K.
2015-12-01
Since the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, intensive monitoring and modeling works on radionuclide transfer in environment have been carried out. Although Cesium (Cs) concentration has been attenuating due to both physical and environmental half-life (i.e., wash-off by water and sediment), the attenuation rate depends clearly on the type of land use and land cover. In the Fukushima case, studying the migration in forest land use is important for predicting the long-term behavior of Cs because most of the contaminated region is covered by forests. Atmospheric fallout is characterized by complicated behavior in biogeochemical cycle in forests which can be described by biotic/abiotic interactions between many components. In developing conceptual and mathematical model on Cs transfer in forest ecosystem, defining the dominant components and their interactions are crucial issues (BIOMASS, 1997-2001). However, the modeling of fate and transport in geosphere after Cs exports from the forest ecosystem is often ignored. An integrated watershed modeling for simulating spatiotemporal redistribution of Cs that includes the entire region from source to mouth and surface to subsurface, has been recently developed. Since the deposited Cs can migrate due to water and sediment movement, the different species (i.e., dissolved and suspended) and their interactions are key issues in the modeling. However, the initial inventory as source-term was simplified to be homogeneous and time-independent, and biogeochemical cycle in forests was not explicitly considered. Consequently, it was difficult to evaluate the regionally-inherent characteristics which differ according to land uses, even if the model was well calibrated. In this study, we combine the different advantages in modeling of forest ecosystem and watershed. This enable to include more realistic Cs deposition and time series of inventory can be forced over the land surface. These processes are integrated into the watershed simulator GETFLOWS coupled with biogeochemical cycling in forests. We present brief a overview of the simulator and an application for reservoir basin.
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Aquatic biodiversity in forests: A weak link in ecosystem services resilience
Penaluna, Brooke E.; Olson, Deanna H.; Flitcroft, Rebecca L; Weber, Matthew A.; Bellmore, J. Ryan; Wondzell, Steven M.; Dunham, Jason B.; Johnson, Sherri L.; Reeves, Gordon H.
2017-01-01
The diversity of aquatic ecosystems is being quickly reduced on many continents, warranting a closer examination of the consequences for ecological integrity and ecosystem services. Here we describe intermediate and final ecosystem services derived from aquatic biodiversity in forests. We include a summary of the factors framing the assembly of aquatic biodiversity in forests in natural systems and how they change with a variety of natural disturbances and human-derived stressors. We consider forested aquatic ecosystems as a multi-state portfolio, with diverse assemblages and life-history strategies occurring at local scales as a consequence of a mosaic of habitat conditions and past disturbances and stressors. Maintaining this multi-state portfolio of assemblages requires a broad perspective of ecosystem structure, various functions, services, and management implications relative to contemporary stressors. Because aquatic biodiversity provides multiple ecosystem services to forests, activities that compromise aquatic ecosystems and biodiversity could be an issue for maintaining forest ecosystem integrity. We illustrate these concepts with examples of aquatic biodiversity and ecosystem services in forests of northwestern North America, also known as Northeast Pacific Rim. Encouraging management planning at broad as well as local spatial scales to recognize multi-state ecosystem management goals has promise for maintaining valuable ecosystem services. Ultimately, integration of information from socio-ecological ecosystems will be needed to maintain ecosystem services derived directly and indirectly from forest aquatic biota.
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Paying for Forest Ecosystem Services: Voluntary Versus Mandatory Payments.
Roesch-McNally, Gabrielle E; Rabotyagov, Sergey S
2016-03-01
The emergence of new markets for forest ecosystem services can be a compelling opportunity for market diversification for private forest landowners, while increasing the provision of public goods from private lands. However, there is limited information available on the willingness-to-pay (WTP) for specific forest ecosystem services, particularly across different ecosystem market mechanisms. We utilize survey data from Oregon and Washington households to compare marginal WTP for forest ecosystem services and the total WTP for cost-effective bundles of forest ecosystem services obtained from a typical Pacific Northwest forest across two value elicitation formats representing two different ecosystem market mechanisms: an incentive-compatible choice experiment involving mandatory tax payments and a hypothetical private provision scenario modeled as eliciting contributions to the preferred forest management alternative via a provision point mechanism with a refund. A representative household's total WTP for the average forest management program was estimated at $217.59 per household/year under a mandatory tax mechanism and $160.44 per household/per year under a voluntary, crowdfunding-style, contribution mechanism; however, these estimates are not statistically different. Marginal WTP estimates were assessed for particular forest ecosystem service attributes including water quality, carbon storage, mature forest habitat, and public recreational access. This study finds that survey respondents place significant economic value on forest ecosystem services in both elicitation formats and that the distributions of the marginal WTP are not statistically significantly different.
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Paying for Forest Ecosystem Services: Voluntary Versus Mandatory Payments
NASA Astrophysics Data System (ADS)
Roesch-McNally, Gabrielle E.; Rabotyagov, Sergey S.
2016-03-01
The emergence of new markets for forest ecosystem services can be a compelling opportunity for market diversification for private forest landowners, while increasing the provision of public goods from private lands. However, there is limited information available on the willingness-to-pay (WTP) for specific forest ecosystem services, particularly across different ecosystem market mechanisms. We utilize survey data from Oregon and Washington households to compare marginal WTP for forest ecosystem services and the total WTP for cost-effective bundles of forest ecosystem services obtained from a typical Pacific Northwest forest across two value elicitation formats representing two different ecosystem market mechanisms: an incentive-compatible choice experiment involving mandatory tax payments and a hypothetical private provision scenario modeled as eliciting contributions to the preferred forest management alternative via a provision point mechanism with a refund. A representative household's total WTP for the average forest management program was estimated at 217.59 per household/year under a mandatory tax mechanism and 160.44 per household/per year under a voluntary, crowdfunding-style, contribution mechanism; however, these estimates are not statistically different. Marginal WTP estimates were assessed for particular forest ecosystem service attributes including water quality, carbon storage, mature forest habitat, and public recreational access. This study finds that survey respondents place significant economic value on forest ecosystem services in both elicitation formats and that the distributions of the marginal WTP are not statistically significantly different.
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Ren, Hai; Li, Linjun; Liu, Qiang; Wang, Xu; Li, Yide; Hui, Dafeng; Jian, Shuguang; Wang, Jun; Yang, Huai; Lu, Hongfang; Zhou, Guoyi; Tang, Xuli; Zhang, Qianmei; Wang, Dong; Yuan, Lianlian; Chen, Xubing
2014-01-01
Spatial and temporal patterns of carbon (C) storage in forest ecosystems significantly affect the terrestrial C budget, but such patterns are unclear in the forests in Hainan Province, the largest tropical island in China. Here, we estimated the spatial and temporal patterns of C storage from 1993-2008 in Hainan's forest ecosystems by combining our measured data with four consecutive national forest inventories data. Forest coverage increased from 20.7% in the 1950s to 56.4% in the 2010s. The average C density of 163.7 Mg C/ha in Hainan's forest ecosystems in this study was slightly higher than that of China's mainland forests, but was remarkably lower than that in the tropical forests worldwide. Total forest ecosystem C storage in Hainan increased from 109.51 Tg in 1993 to 279.17 Tg in 2008. Soil C accounted for more than 70% of total forest ecosystem C. The spatial distribution of forest C storage in Hainan was uneven, reflecting differences in land use change and forest management. The potential carbon sequestration of forest ecosystems was 77.3 Tg C if all forested lands were restored to natural tropical forests. To increase the C sequestration potential on Hainan Island, future forest management should focus on the conservation of natural forests, selection of tree species, planting of understory species, and implementation of sustainable practices.
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Tang, Xuli; Zhang, Qianmei; Wang, Dong; Yuan, Lianlian; Chen, Xubing
2014-01-01
Spatial and temporal patterns of carbon (C) storage in forest ecosystems significantly affect the terrestrial C budget, but such patterns are unclear in the forests in Hainan Province, the largest tropical island in China. Here, we estimated the spatial and temporal patterns of C storage from 1993–2008 in Hainan's forest ecosystems by combining our measured data with four consecutive national forest inventories data. Forest coverage increased from 20.7% in the 1950s to 56.4% in the 2010s. The average C density of 163.7 Mg C/ha in Hainan's forest ecosystems in this study was slightly higher than that of China's mainland forests, but was remarkably lower than that in the tropical forests worldwide. Total forest ecosystem C storage in Hainan increased from 109.51 Tg in 1993 to 279.17 Tg in 2008. Soil C accounted for more than 70% of total forest ecosystem C. The spatial distribution of forest C storage in Hainan was uneven, reflecting differences in land use change and forest management. The potential carbon sequestration of forest ecosystems was 77.3 Tg C if all forested lands were restored to natural tropical forests. To increase the C sequestration potential on Hainan Island, future forest management should focus on the conservation of natural forests, selection of tree species, planting of understory species, and implementation of sustainable practices. PMID:25229628
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[Characteristics of carbon storage of Inner Mongolia forests: a review].
Yang, Hao; Hu, Zhong-Min; Zhang, Lei-Ming; Li, Sheng-Gong
2014-11-01
Forests in Inner Mongolia account for an important part of the forests in China in terms of their large area and high living standing volume. This study reported carbon storage, carbon density, carbon sequestration rate and carbon sequestration potential of forest ecosystems in Inner Mongolia using the biomass carbon data from the related literature. Through analyzing the data of forest inventory and the generalized allometric equations between volume and biomass, previous studies had reported that biomass carbon storage of the forests in Inner Mongolia was about 920 Tg C, which was 12 percent of the national forest carbon storage, the annual average growth rate was about 1.4%, and the average of carbon density was about 43 t · hm(-2). Carbon storage and carbon density showed an increasing trend over time. Coniferous and broad-leaved mixed forest, Pinus sylvestris var. mongolica forest and Betula platyphylla forest had higher carbon sequestration capacities. Carbon storage was reduced due to human activities such as thinning and clear cutting. There were few studies on carbon storage of the forests in Inner Mongolia with focus on the soil, showing that the soil car- bon density increased with the stand age. Study on the carbon sequestration potential of forest ecosystems was still less. Further study was required to examine dynamics of carbon storage in forest ecosystems in Inner Mongolia, i. e., to assess carbon storage in the forest soils together with biomass carbon storage, to compute biomass carbon content of species organs as 45% in the allometric equations, to build more species-specific and site-specific allometric equations including root biomass for different dominant species, and to take into account the effects of climate change on carbon sequestration rate and carbon sequestration potential.
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Environmental drivers of Ixodes ricinus abundance in forest fragments of rural European landscapes.
Ehrmann, Steffen; Liira, Jaan; Gärtner, Stefanie; Hansen, Karin; Brunet, Jörg; Cousins, Sara A O; Deconchat, Marc; Decocq, Guillaume; De Frenne, Pieter; De Smedt, Pallieter; Diekmann, Martin; Gallet-Moron, Emilie; Kolb, Annette; Lenoir, Jonathan; Lindgren, Jessica; Naaf, Tobias; Paal, Taavi; Valdés, Alicia; Verheyen, Kris; Wulf, Monika; Scherer-Lorenzen, Michael
2017-09-06
The castor bean tick (Ixodes ricinus) transmits infectious diseases such as Lyme borreliosis, which constitutes an important ecosystem disservice. Despite many local studies, a comprehensive understanding of the key drivers of tick abundance at the continental scale is still lacking. We analyze a large set of environmental factors as potential drivers of I. ricinus abundance. Our multi-scale study was carried out in deciduous forest fragments dispersed within two contrasting rural landscapes of eight regions, along a macroclimatic gradient stretching from southern France to central Sweden and Estonia. We surveyed the abundance of I. ricinus, plant community composition, forest structure and soil properties and compiled data on landscape structure, macroclimate and habitat properties. We used linear mixed models to analyze patterns and derived the relative importance of the significant drivers. Many drivers had, on their own, either a moderate or small explanatory value for the abundance of I. ricinus, but combined they explained a substantial part of variation. This emphasizes the complex ecology of I. ricinus and the relevance of environmental factors for tick abundance. Macroclimate only explained a small fraction of variation, while properties of macro- and microhabitat, which buffer macroclimate, had a considerable impact on tick abundance. The amount of forest and the composition of the surrounding rural landscape were additionally important drivers of tick abundance. Functional (dispersules) and structural (density of tree and shrub layers) properties of the habitat patch played an important role. Various diversity metrics had only a small relative importance. Ontogenetic tick stages showed pronounced differences in their response. The abundance of nymphs and adults is explained by the preceding stage with a positive relationship, indicating a cumulative effect of drivers. Our findings suggest that the ecosystem disservices of tick-borne diseases, via the abundance of ticks, strongly depends on habitat properties and thus on how humans manage ecosystems from the scale of the microhabitat to the landscape. This study stresses the need to further evaluate the interaction between climate change and ecosystem management on I. ricinus abundance.
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Pervasive growth reduction in Norway spruce forests following wind disturbance.
Seidl, Rupert; Blennow, Kristina
2012-01-01
In recent decades the frequency and severity of natural disturbances by e.g., strong winds and insect outbreaks has increased considerably in many forest ecosystems around the world. Future climate change is expected to further intensify disturbance regimes, which makes addressing disturbances in ecosystem management a top priority. As a prerequisite a broader understanding of disturbance impacts and ecosystem responses is needed. With regard to the effects of strong winds--the most detrimental disturbance agent in Europe--monitoring and management has focused on structural damage, i.e., tree mortality from uprooting and stem breakage. Effects on the functioning of trees surviving the storm (e.g., their productivity and allocation) have been rarely accounted for to date. Here we show that growth reduction was significant and pervasive in a 6.79 million hectare forest landscape in southern Sweden following the storm Gudrun (January 2005). Wind-related growth reduction in Norway spruce (Picea abies (L.) Karst.) forests surviving the storm exceeded 10% in the worst hit regions, and was closely related to maximum gust wind speed (R(2) = 0.849) and structural wind damage (R(2) = 0.782). At the landscape scale, wind-related growth reduction amounted to 3.0 million m(3) in the three years following Gudrun. It thus exceeds secondary damage from bark beetles after Gudrun as well as the long-term average storm damage from uprooting and stem breakage in Sweden. We conclude that the impact of strong winds on forest ecosystems is not limited to the immediately visible area of structural damage, and call for a broader consideration of disturbance effects on ecosystem structure and functioning in the context of forest management and climate change mitigation.
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Pervasive Growth Reduction in Norway Spruce Forests following Wind Disturbance
Seidl, Rupert; Blennow, Kristina
2012-01-01
Background In recent decades the frequency and severity of natural disturbances by e.g., strong winds and insect outbreaks has increased considerably in many forest ecosystems around the world. Future climate change is expected to further intensify disturbance regimes, which makes addressing disturbances in ecosystem management a top priority. As a prerequisite a broader understanding of disturbance impacts and ecosystem responses is needed. With regard to the effects of strong winds – the most detrimental disturbance agent in Europe – monitoring and management has focused on structural damage, i.e., tree mortality from uprooting and stem breakage. Effects on the functioning of trees surviving the storm (e.g., their productivity and allocation) have been rarely accounted for to date. Methodology/Principal Findings Here we show that growth reduction was significant and pervasive in a 6.79·million hectare forest landscape in southern Sweden following the storm Gudrun (January 2005). Wind-related growth reduction in Norway spruce (Picea abies (L.) Karst.) forests surviving the storm exceeded 10% in the worst hit regions, and was closely related to maximum gust wind speed (R2 = 0.849) and structural wind damage (R2 = 0.782). At the landscape scale, wind-related growth reduction amounted to 3.0 million m3 in the three years following Gudrun. It thus exceeds secondary damage from bark beetles after Gudrun as well as the long-term average storm damage from uprooting and stem breakage in Sweden. Conclusions/Significance We conclude that the impact of strong winds on forest ecosystems is not limited to the immediately visible area of structural damage, and call for a broader consideration of disturbance effects on ecosystem structure and functioning in the context of forest management and climate change mitigation. PMID:22413012
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Climate Change and Ecosystem Services Output Efficiency in Southern Loblolly Pine Forests.
Susaeta, Andres; Adams, Damian C; Carter, Douglas R; Dwivedi, Puneet
2016-09-01
Forests provide myriad ecosystem services that are vital to humanity. With climate change, we expect to see significant changes to forests that will alter the supply of these critical services and affect human well-being. To better understand the impacts of climate change on forest-based ecosystem services, we applied a data envelopment analysis method to assess plot-level efficiency in the provision of ecosystem services in Florida natural loblolly pine (Pinus taeda L.) forests. Using field data for n = 16 loblolly pine forest plots, including inputs such as site index, tree density, age, precipitation, and temperatures for each forest plot, we assessed the relative plot-level production of three ecosystem services: timber, carbon sequestered, and species richness. The results suggested that loblolly pine forests in Florida were largely inefficient in the provision of these ecosystem services under current climatic conditions. Climate change had a small negative impact on the loblolly pine forests efficiency in the provision of ecosystem services. In this context, we discussed the reduction of tree density that may not improve ecosystem services production.
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Climate Change and Ecosystem Services Output Efficiency in Southern Loblolly Pine Forests
NASA Astrophysics Data System (ADS)
Susaeta, Andres; Adams, Damian C.; Carter, Douglas R.; Dwivedi, Puneet
2016-09-01
Forests provide myriad ecosystem services that are vital to humanity. With climate change, we expect to see significant changes to forests that will alter the supply of these critical services and affect human well-being. To better understand the impacts of climate change on forest-based ecosystem services, we applied a data envelopment analysis method to assess plot-level efficiency in the provision of ecosystem services in Florida natural loblolly pine ( Pinus taeda L.) forests. Using field data for n = 16 loblolly pine forest plots, including inputs such as site index, tree density, age, precipitation, and temperatures for each forest plot, we assessed the relative plot-level production of three ecosystem services: timber, carbon sequestered, and species richness. The results suggested that loblolly pine forests in Florida were largely inefficient in the provision of these ecosystem services under current climatic conditions. Climate change had a small negative impact on the loblolly pine forests efficiency in the provision of ecosystem services. In this context, we discussed the reduction of tree density that may not improve ecosystem services production.
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This EnviroAtlas dataset contains polygons depicting the geographic areas of market-based programs, referred to herein as markets, and projects addressing ecosystem services protection in the United States. Depending upon the type of market or project and data availability, polygons reflect market coverage areas, project footprints, or project primary impact areas in which ecosystem service markets and projects operate. The data were collected via surveys and desk research conducted by Forest Trends' Ecosystem Marketplace from 2008 to 2016 on biodiversity (i.e., imperiled species/habitats; wetlands and streams), carbon, and water markets. Additional biodiversity data were obtained from the Regulatory In-lieu Fee and Bank Information Tracking System (RIBITS) database in 2015. Attribute data include information regarding the methodology, design, and development of biodiversity, carbon, and water markets and projects. This dataset was produced by Forest Trends' Ecosystem Marketplace for EnviroAtlas in order to support public access to and use of information related to environmental markets. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about thi
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Hurteau, Matthew D
2017-01-01
Climate projections for the southwestern US suggest a warmer, drier future and have the potential to impact forest carbon (C) sequestration and post-fire C recovery. Restoring forest structure and surface fire regimes initially decreases total ecosystem carbon (TEC), but can stabilize the remaining C by moderating wildfire behavior. Previous research has demonstrated that fire maintained forests can store more C over time than fire suppressed forests in the presence of wildfire. However, because the climate future is uncertain, I sought to determine the efficacy of forest management to moderate fire behavior and its effect on forest C dynamics under current and projected climate. I used the LANDIS-II model to simulate carbon dynamics under early (2010-2019), mid (2050-2059), and late (2090-2099) century climate projections for a ponderosa pine (Pinus ponderosa) dominated landscape in northern Arizona. I ran 100-year simulations with two different treatments (control, thin and burn) and a 1 in 50 chance of wildfire occurring. I found that control TEC had a consistent decline throughout the simulation period, regardless of climate. Thin and burn TEC increased following treatment implementation and showed more differentiation than the control in response to climate, with late-century climate having the lowest TEC. Treatment efficacy, as measured by mean fire severity, was not impacted by climate. Fire effects were evident in the cumulative net ecosystem exchange (NEE) for the different treatments. Over the simulation period, 32.8-48.9% of the control landscape was either C neutral or a C source to the atmosphere and greater than 90% of the thin and burn landscape was a moderate C sink. These results suggest that in southwestern ponderosa pine, restoring forest structure and surface fire regimes provides a reasonable hedge against the uncertainty of future climate change for maintaining the forest C sink.
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2017-01-01
Climate projections for the southwestern US suggest a warmer, drier future and have the potential to impact forest carbon (C) sequestration and post-fire C recovery. Restoring forest structure and surface fire regimes initially decreases total ecosystem carbon (TEC), but can stabilize the remaining C by moderating wildfire behavior. Previous research has demonstrated that fire maintained forests can store more C over time than fire suppressed forests in the presence of wildfire. However, because the climate future is uncertain, I sought to determine the efficacy of forest management to moderate fire behavior and its effect on forest C dynamics under current and projected climate. I used the LANDIS-II model to simulate carbon dynamics under early (2010–2019), mid (2050–2059), and late (2090–2099) century climate projections for a ponderosa pine (Pinus ponderosa) dominated landscape in northern Arizona. I ran 100-year simulations with two different treatments (control, thin and burn) and a 1 in 50 chance of wildfire occurring. I found that control TEC had a consistent decline throughout the simulation period, regardless of climate. Thin and burn TEC increased following treatment implementation and showed more differentiation than the control in response to climate, with late-century climate having the lowest TEC. Treatment efficacy, as measured by mean fire severity, was not impacted by climate. Fire effects were evident in the cumulative net ecosystem exchange (NEE) for the different treatments. Over the simulation period, 32.8–48.9% of the control landscape was either C neutral or a C source to the atmosphere and greater than 90% of the thin and burn landscape was a moderate C sink. These results suggest that in southwestern ponderosa pine, restoring forest structure and surface fire regimes provides a reasonable hedge against the uncertainty of future climate change for maintaining the forest C sink. PMID:28046079
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Fenn, M.E.; Poth, M.A.; Aber, J.D.; Baron, Jill S.; Bormann, B.T.; Johnson, D.W.; Lemly, A.D.; McNulty, S.G.; Ryan, D.F.; Stottlemyer, R.
1998-01-01
Most forests in North America remain nitrogen limited, although recent studies have identified forested areas that exhibit symptoms of N excess, analogous to overfertilization of arable land. Nitrogen excess in watersheds is detrimental because of disruptions in plant/soil nutrient relations, increased soil acidification and aluminum mobility, increased emissions of nitrogenous greenhouse gases from soil, reduced methane consumption in soil, decreased water quality, toxic effects on freshwater biota, and eutrophication of coastal marine waters. Elevated nitrate (NO3/-) loss to groundwater or surface waters is the primary symptom of N excess. Additional symptoms include increasing N concentrations and higher N:nutrient ratios in foliage (i.e., N:Mg, N:P), foliar accumulation of amino acids or NO3/-, and low soil C:N ratios. Recent nitrogen-fertilization studies in New England and Europe provide preliminary evidence that some forests receiving chronic N inputs may decline in productivity and experience greater mortality. Long-term fertilization at Mount Ascutney, Vermont, suggests that declining and slow N-cycling coniferous stands may be replaced by fast-growing and fast N-cycling deciduous forests. Symptoms of N saturation are particularly severe in high-elevation, nonaggrading spruce-fir ecosystems in the Appalachian Mountains and in eastern hardwood watersheds at the Fernow Experimental Forest near Parsons, West Virginia. In the Los Angeles Air Basin, mixed conifer forests and chaparral watersheds with high smog exposure are N saturated and exhibit the highest streamwater NO3/- concentrations for wildlands in North America. High-elevation alpine watersheds in the Colorado Front Range and a deciduous forest in Ontario, Canada, are N saturated, although N deposition is moderate (~8 kg??ha-1??yr-1). In contrast, the Harvard Forest hardwood stand in Massachusetts has absorbed >900 kg N/ha during 8 yr of N amendment studies without significant NO3/- leaching, illustrating that ecosystems vary widely in the capacity to retain N inputs. Overly mature forests with high N deposition, high soil N stores, and low soil C:N ratios are prone to N saturation and NO3/- leaching. Additional characteristics favoring low N retention capacity include a short growing season (reduced plant N demand) and reduced contact time between drainage water and soil (i.e., porous coarse-textured soils, exposed bedrock or talus). Temporal patterns of hydrologic fluxes interact with biotic uptake and internal cycling patterns in determining ecosystem N retention. Soils are the largest storage pool for N inputs, although vegetation uptake is also important. Recent studies indicate that nitrification may be widespread in undisturbed ecosystems, and that microbial assimilation of NO3/- may be a significant N retention mechanism, contrary to previous assumptions. Further studies are needed to elucidate the sites, forms, and mechanisms of N retention and incorporation into soil organic matter, and to test potential management options for mitigating N losses from forests. Implementation of intensive management practices in N-saturated ecosystems may only be feasible in high-priority areas and on a limited scale. Reduction of N emissions would be a preferable solution, although major reductions in the near future are unlikely in many areas due to economic, energy-use, policy, and demographic considerations.
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NASA Astrophysics Data System (ADS)
Nordin, Annika; Strengbom, Joachim; From, Fredrik
2014-05-01
In management of boreal forests, nitrogen (N) enrichment from atmospheric deposition or from forest fertilization can appear in combination with land-use related disturbances, i.e. tree harvesting by clear-felling. Long-term interactive effects between N enrichment and disturbance on boreal forest ecosystem structure and function are, however, poorly known. We investigated effects of N enrichment by forest fertilization done > 25 years ago on forest understory species composition in old-growth (undisturbed) forests, and in forests clear-felled 10 years ago (disturbed). In clear-felled forests we also investigated effects of the previous N addition on growth of tree saplings. The results show that the N enrichment effect on the understory species composition was strongly dependent on the disturbance caused by clear-felling. In undisturbed forests, there were small or no effects on understory species composition from N addition. In contrast, effects were large in forests first exposed to N addition and subsequently disturbed by clear-felling. Effects of N addition differed among functional groups of plants. Abundance of graminoids increased (+232%) and abundance of dwarf shrubs decreased (-44%) following disturbance in N fertilized forests. For vascular plants, the two perturbations had contrasting effects on α-(within forests) and β-diversity (among forests): in disturbed forests, N addition reduced, or had no effect on α-diversity, while β-diversity increased. For bryophytes, negative effects of disturbance on α-diversity were smaller in N fertilized forests than in forests not fertilized, while neither N addition nor disturbance had any effects on β-diversity. Moreover, sapling growth in forests clear-felled 10 years ago was significantly higher in previously N fertilized forests than in forests not fertilized. Our study show that effects of N addition on plant communities may appear small, short-lived, or even absent until exposed to a disturbance. This highlights the importance of considering interactive effects with disturbance when evaluating long-term effects of N enrichment on boreal forest ecosystem structure and function.
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NASA Astrophysics Data System (ADS)
Havránková, Kateřina; Taufarová, Klára; Šigut, Ladislav; McGloin, Ryan; Acosta, Manuel; Dušek, Jiří; Krupková, Lenka; Macálková-Mžourková, Lenka; Pavelka, Marian; Dařenová, Eva; Yadav, Shilpi; Nguyen, Vinh; Guerra, Carlos; Janous, Dalibor; Marek, Michal V.
2017-04-01
The Global Change Research Institute of the Czech Academy of Sciences (CzechGlobe) have established a well-equipped network of ecosystem stations, with modern instrumentation for eco-physiological, plant physiological and micrometeorological studies, and estimation of GHG emissions. The network of stations (CzeCOS) covers the main terrestrial ecosystems of the Czech Republic (young and old coniferous forest, deciduous forest, mixed floodplain forest, grassland, wetland and cropland). The ecosystem stations are equipped with eddy covariance systems, soil and stem chamber systems for CO2 efflux and instruments for making micrometeorological measurements. The network enables detailed research to be conducted on topics such as: the carbon balance of different ecosystems, energy balance closure, the impact of current climate conditions on production and ecosystem disturbances during extreme weather conditions (drought, floods, winter storms, etc.) at regional, national and international scales. As a part of global networks (Fluxnet, ANAEe, ICOS), CzeCOS participates in evaluating and predicting environmental change and helps in the proposal of mitigation measures. Another important issue studied at some of the CzeCOS sites is the use of the eddy covariance method in sloping terrain in order to improve eddy covariance data processing for sites in this kind of terrain. Here we show specific results from the sites and outline the importance of the regional/national network for improving our knowledge about the exchange of matter and energy fluxes at different ecosystems. This study was supported by the Ministry of Education, Youth and Sports of CR within the National Sustainability Program I (NPU I), grant number LO1415 and LD 15040. Computational resources were provided by the CESNET LM2015042 and the CERIT Scientific Cloud LM2015085, provided under the programme "Projects of Large Research, Development, and Innovations Infrastructures".
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DOE Office of Scientific and Technical Information (OSTI.GOV)
McCollom, M.
1979-01-01
The existing terrestrial ecosystems at the plant site and impacts on them are described. The following are discussed for the fuelwood harvest region: forest soils, forest types and ecological succession, nutrient cycles in the forest ecosystem, fauna of the ecosystem, forest practices in the harvest region, and long-term productivity of the forest resource. (MHR)
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Quantification of soil respiration in forest ecosystems across China
NASA Astrophysics Data System (ADS)
Song, Xinzhang; Peng, Changhui; Zhao, Zhengyong; Zhang, Zhiting; Guo, Baohua; Wang, Weifeng; Jiang, Hong; Zhu, Qiuan
2014-09-01
We collected 139 estimates of the annual forest soil CO2 flux and 173 estimates of the Q10 value (the temperature sensitivity) assembled from 90 published studies across Chinese forest ecosystems. We analyzed the annual soil respiration (Rs) rates and the temperature sensitivities of seven forest ecosystems, including evergreen broadleaf forests (EBF), deciduous broadleaf forests (DBF), broadleaf and needleleaf mixed forests (BNMF), evergreen needleleaf forests (ENF), deciduous needleleaf forests (DNF), bamboo forests (BF) and shrubs (SF). The results showed that the mean annual Rs rate was 33.65 t CO2 ha-1 year-1 across Chinese forest ecosystems. Rs rates were significantly different (P < 0.001) among the seven forest types, and were significantly and positively influenced by mean annual temperature (MAT), mean annual precipitation (MAP), and actual evapotranspiration (AET); but negatively affected by latitude and elevation. The mean Q10 value of 1.28 was lower than the world average (1.4-2.0). The Q10 values derived from the soil temperature at a depth of 5 cm varied among forest ecosystems by an average of 2.46 and significantly decreased with the MAT but increased with elevation and latitude. Moreover, our results suggested that an artificial neural network (ANN) model can effectively predict Rs across Chinese forest ecosystems. This study contributes to better understanding of Rs across Chinese forest ecosystems and their possible responses to global warming.
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NASA Astrophysics Data System (ADS)
Toda, M.; Knohl, A.; Herbst, M.; Keenan, T. F.; Yokozawa, M.
2016-12-01
The increase in extreme climate events associated with ongoing global warming may create severe damage to terrestrial ecosystems, changing plant structure and the eco-physiological functions that regulate ecosystem carbon exchange. However, most damage is usually due to moderate, rather than catastrophic, disturbances. The nature of plant functional responses to such disturbances, and the resulting effects on the terrestrial carbon cycle, remain poorly understood. To unravel the scientific question, tower-based eddy covariance data in the cool-temperate forests were used to constrain plant eco-physiological parameters in a persimoneous ecosystem model that may have affected carbon dynamics following extreme climate events using the statistic Bayesian inversion approach. In the present study, we raised two types of extreme events relevant for cool-temperate regions, i.e. a typhoon with mechanistic foliage destraction and a heat wave with severe drought. With appropriate evaluation of parameter and predictive uncertainties, the inversion analysis shows annual trajectory of activated photosynthetic responses following climate extremes compared the pre-disturbance state in each forest. We address that forests with moderate disturbance show substantial and rapid photosynthetic recovery, enhanced productivity, and, thus, ecosystem carbon exchange, although the effect of extreme climatic events varies depending on the stand successional phase and the type, intensity, timing and legacy of the disturbance.
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Lipatov, D N; Shcheglov, A I; Tsvetnova, O B
2007-01-01
The paper deals with a comparative study of 137Cs contamination in forest, old arable and cultivated soils of Tula Region. Initial interception of Chernobyl derived 137Cs is higher in forest ecosystems: oak-forest > birch-forest > pine-forest > agricultural ecosystems. Vertical migration of 137Cs in deeper layers of soils was intensive in agricultural ecosystems: cultivated soils > old arable soils > birch-forest soils > oak-forest soils > pine-forest soils. In study have been evaluated spatial variability of 137Cs in soil and asymmetrical distribution, that is a skew to the right. Spatial heterogeneity of 137Cs in agricultural soils is much lower than in forest soils. For cultivated soil are determined the rate of resuspension, which equal to 6.1 x 10(-4) day(-1). For forest soils are described the 137Cs concentration in litter of different ecosystems. The role of main accumulation and barrier of 137Cs retain higher layers of soils (horizon A1(A1E) in forest, horizon Ap in agricultural ecosystems) in long-term forecast after Chernobyl accident.
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Biogeochemical and metabolic responses to the flood pulse in a semiarid floodplain
Valett, H.M.; Baker, M.A.; Morrice, J.A.; Crawford, C.S.; Molles, M.C.; Dahm, Clifford N.; Moyer, D.L.; Thibault, J.R.; Ellis, L.M.
2005-01-01
Flood pulse inundation of riparian forests alters rates of nutrient retention and organic matter processing in the aquatic ecosystems formed in the forest interior. Along the Middle Rio Grande (New Mexico, USA), impoundment and levee construction have created riparian forests that differ in their inter-flood intervals (IFIs) because some floodplains are still regularly inundated by the flood pulse (i.e., connected), while other floodplains remain isolated from flooding (i.e., disconnected). This research investigates how ecosystem responses to the flood pulse relate to forest IFI by quantifying nutrient and organic matter dynamics in the Rio Grande floodplain during three years of experimental flooding of the disconnected floodplain and during a single year of natural flooding of the connected floodplain. Surface and subsurface conditions in paired sites (control, flood) established in the two floodplain types were monitored to address metabolic and biogeochemical responses. Compared to dry controls, rates of respiration in the flooded sites increased by up to three orders of magnitude during the flood pulse. In the disconnected forest, month-long experimental floods produced widespread anoxia of four-week duration during each of the three years of flooding. In contrast, water in the connected floodplain remained well oxygenated (3-8 ppm). Material budgets for experimental floods showed the disconnected floodplain to be a sink for inorganic nitrogen and suspended solids, but a potential source of dissolved organic carbon (DOC). Compared to the main stem of the Rio Grande, flood-water on the connected floodplain contained less nitrate, but comparable concentrations of DOC, phosphate-phosphorus, and ammonium-nitrogen. Results suggest that floodplain IFI drives metabolic and biogeochemical responses during the flood pulse. Impoundment and fragmentation have altered floodplains from a mosaic of patches with variable IFI to a bimodal distribution. Relatively predictable flooding occurs in the connected forest, while inundation of the disconnected forest occurs only as the result of managed application of water. In semiarid floodplains, water is scarce except during the flood pulse. Ecosystem responses to the flood pulse are related to the IFI and other measures of flooding history that help describe spatial variation in ecosystem function.
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Fine-scale spatial climate variation and drought mediate the likelihood of reburning
Sean A. Parks; Marc‐Andre Parisien; Carol Miller; Lisa M. Holsinger; Larry Scott Baggett
2018-01-01
In many forested ecosystems, it is increasingly recognized that the probability of burning is substantially reduced within the footprint of previously burned areas. This selfâlimiting effect of wildland fire is considered a fundamental emergent property of ecosystems and is partly responsible for structuring landscape heterogeneity (i.e., mosaics of different age...
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Kenneth W. Stolte
2001-01-01
The Forest Health Monitoring (FHM) and Forest Inventory and Analyses (FIA) programs are integrated bilogical monitoring systems that use nationally standardized methods to evaluate and report on the health and sustainability of forest ecosystems in the United States. Many of the anticipated changes in forest ecosystems from climate change were also issues addressed in...
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INSECTS & PATHOGENS Regulators of Forest Ecosystems
Robert A. Haack; James W. Byler
1993-01-01
Today's forest managers are challenged by issues such as soil productivity, biodiversity, threatened and endangered species, and ecosystem sustainability; and ecosystem management has been proposed as a way to deal with them. The Society of American Foresters (1993) defines this term as keeping forest ecosystems functioning well over long periods of time in order...
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Advancement of tree species across ecotonal borders into non-forested ecosystems
NASA Astrophysics Data System (ADS)
Hanberry, Brice B.; Hansen, Mark H.
2015-10-01
Woody species are increasing in density, causing transition to more densely wooded vegetation states, and encroaching across ecotonal borders into non-forested ecosystems. We examined USDA Forest Service Forest Inventory and Analysis data to identify tree species that have expanded longitudinally in range, particularly into the central United States. We analyzed compositional differences within ecological regions (i.e., subsections) in eastern and western ranges of species using repeated measures ANOVA. We considered differences in outer ranges to indicate range expansion or contraction. We also estimated the shift in forest area and basal area relative to the center of the US and compared change in deciduous forest land cover. Out of 80 candidate species, 22 species expanded to the west, seven species expanded to the east, and five species expanded in both directions. During the survey interval, eastern tree species advanced into the predominantly non-forested ecosystems of central United States. Eastern cottonwood, eastern hophornbeam, eastern redbud, honeylocust, Osage-orange, pecan, red mulberry, and Shumard oak represent some of the species that are advancing eastern forest boundaries across forest-grassland ecotones into the central United States. Forest land has shifted towards the center of the continent, as has the center of mean tree basal area, and a simple comparison of deciduous cover change also displayed forest advancement into the central United States from eastern forests. The expanding species may spread along riparian migration corridors that provide protection from drought. Humans use the advancing tree species for windbreaks, fencerows, and ornamental landscaping, while wildlife spread fruit seeds, which results in unintentional assisted migration, or translocation, to drier sites across the region.
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Song, Xiang; Zeng, Xiaodong
2017-02-01
The climate has important influences on the distribution and structure of forest ecosystems, which may lead to vital feedback to climate change. However, much of the existing work focuses on the changes in carbon fluxes or water cycles due to climate change and/or atmospheric CO 2 , and few studies have considered how and to what extent climate change and CO 2 influence the ecosystem structure (e.g., fractional coverage change) and the changes in the responses of ecosystems with different characteristics. In this work, two dynamic global vegetation models (DGVMs): IAP-DGVM coupled with CLM3 and CLM4-CNDV, were used to investigate the response of the forest ecosystem structure to changes in climate (temperature and precipitation) and CO 2 concentration. In the temperature sensitivity tests, warming reduced the global area-averaged ecosystem gross primary production in the two models, which decreased global forest area. Furthermore, the changes in tree fractional coverage (Δ F tree ; %) from the two models were sensitive to the regional temperature and ecosystem structure, i.e., the mean annual temperature (MAT; °C) largely determined whether Δ F tree was positive or negative, while the tree fractional coverage ( F tree ; %) played a decisive role in the amplitude of Δ F tree around the globe, and the dependence was more remarkable in IAP-DGVM. In cases with precipitation change, F tree had a uniformly positive relationship with precipitation, especially in the transition zones of forests (30% < F tree < 60%) for IAP-DGVM and in semiarid and arid regions for CLM4-CNDV. Moreover, Δ F tree had a stronger dependence on F tree than on the mean annual precipitation (MAP; mm/year). It was also demonstrated that both models captured the fertilization effects of the CO 2 concentration.
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NASA Astrophysics Data System (ADS)
Musavi, Talie; Migliavacca, Mirco; Mahecha, Miguel D.; Reichstein, Markus; Kattge, Jens; Wirth, Christian; Black, T. Andrew; Janssens, Ivan; Knohl, Alexander; Loustau, Denis; Roupsard, Olivier; Varlagin, Andrej; Rambal, Serge; Cescatti, Alessandro; Gianelle, Damiano; Kondo, Hiroaki; Tamrakar, Rijan
2017-04-01
Gross primary productivity, GPP, the total uptake of carbon dioxide (CO2) by ecosystems via photosynthesis, is the largest flux in the global carbon cycle. The photosynthetic capacity at light saturation (GPPsat) is a fundamental ecosystem functional property and its interannual variability (IAV) is propagated to the net ecosystem exchange of CO2. In this contribution we made use of a variety of data streams consisting of ecosystem-atmosphere CO2 fluxes measured at eddy covariance flux sites with more than 4 years of data, the GPPsat derived at the different sites, information about climate (temperature, precipitation, and water availability index - WAI), biodiversity information and species richness, stand age, and plant traits, nutrient availability indexes derived from field campaigns, ancillary databases, and the literature. We also used data about forest structure derived from satellite products. Sites were selected according to the availability of eddy covariance flux measurements for at least 4 years, information about stand age, canopy cover, canopy height, and species abundance. The resulting global database consisted of 50 sites with different vegetation types across different climatic regions. Considering the importance of the understanding of IAV in CO2 fluxes to improve the predictive capacity of the global carbon cycle we analyzed a range of alternative hypotheses and potential drivers of the magnitude of IAV in GPPsat in forest ecosystems. The results show that the IAV in GPPsat within sites is driven by climate (i.e. fluctuations in air temperature and soil water availability), but the magnitude of IAV in GPPsat is related to ecosystem structure, and more in details to stand age and biodiversity (R2=0.55, p<0.0001). We conclude that irrespective of forest type the IAV of GPPsat in older and more diverse forests is dampened, and is higher in younger forests with few dominant species.
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Assessment of forest fuel loadings in Puerto Rico and the US Virgin Islands
Thomas J. Brandeis; Christopher W. Woodall
2008-01-01
Quantification of the downed woody materials that comprise forest fuels has gained importance in Caribbean forest ecosystems due to the increasing incidence and severity of wildfires on island ecosystems. Because large-scale assessments of forest fuels have rarely been conducted for these ecosystems, forest fuels were assessed at 121 US Department of Agriculture forest...
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Modeling extreme drought impacts on terrestrial ecosystems when thresholds are exceeded
NASA Astrophysics Data System (ADS)
Holm, J. A.; Rammig, A.; Smith, B.; Medvigy, D.; Lichstein, J. W.; Dukes, J. S.; Allen, C. D.; Beier, C.; Larsen, K. S.; Ficken, C. D.; Pockman, W.; Anderegg, W.; Luo, Y.
2016-12-01
Recent IPCC Assessment Reports suggest that with predicted climate changes future precipitation- and heat-related extreme events are becoming stronger and more frequent with potential for prolonged droughts. To prepare for these changes and their impacts, we need to develop a better understanding of terrestrial ecosystem responses to extreme drought events. In particular, we focus here on large-extent and long-lasting extreme drought events with noticeable impacts on the functioning of forested ecosystems. While most of ecosystem manipulative experiments have been motivated by ongoing and predicted climate change, the majority only applied relatively moderate droughts, not addressing the "very" extreme tail of these scenarios, i.e. "extreme extremes (EEs)". We explore the response of forest ecosystems to EEs using two demographic-based dynamic global vegetation models (DGVMs) (i.e. ED2, LPJ-GUESS) in which the abundances of different plant functional types, as well as tree size- and age-class structure, are emergent properties of resource competition. We evaluate the model's capabilities to represent extreme drought scenarios (i.e., 50% and 90% reduction in precipitation for 1-year, 2-year, and 4-year drought scenarios) at two dry forested sites: Palo Verde, Costa Rica (i.e. tropical) and EucFACE, Australia (i.e. temperate). Through the DGVM modeling outcomes we determine the following five testable hypotheses for future experiments: 1) EEs cannot be extrapolated from mild extremes due to plant plasticity and functional composition. 2) Response to EEs depends on functional diversity, trait combinations, and phenology, such that both models predicted even after 100 years plant biomass did not recover. 3) Mortality from drought reduces the pressure on resources and prevents further damage by subsequent years of drought. 4) Early successional stands are more vulnerable to extreme droughts while older stand are more resilient. 5) Elevated atmospheric CO2 alleviates impacts of extreme droughts while increased temperature exacerbates mortality. This study highlighted a number of questions about our current understanding of EEs and their corresponding thresholds and tipping points, and provides an analysis of confidence in model representation and accuracy of processes related to EEs.
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A conceptual framework: redefining forest soil's critical acid loads under a changing climate.
McNulty, Steven G; Boggs, Johnny L
2010-06-01
Federal agencies of several nations have or are currently developing guidelines for critical forest soil acid loads. These guidelines are used to establish regulations designed to maintain atmospheric acid inputs below levels shown to damage forests and streams. Traditionally, when the critical soil acid load exceeds the amount of acid that the ecosystem can absorb, it is believed to potentially impair forest health. The excess over the critical soil acid load is termed the exceedance, and the larger the exceedance, the greater the risk of ecosystem damage. This definition of critical soil acid load applies to exposure of the soil to a single, long-term pollutant (i.e., acidic deposition). However, ecosystems can be simultaneously under multiple ecosystem stresses and a single critical soil acid load level may not accurately reflect ecosystem health risk when subjected to multiple, episodic environmental stress. For example, the Appalachian Mountains of western North Carolina receive some of the highest rates of acidic deposition in the eastern United States, but these levels are considered to be below the critical acid load (CAL) that would cause forest damage. However, the area experienced a moderate three-year drought from 1999 to 2002, and in 2001 red spruce (Picea rubens Sarg.) trees in the area began to die in large numbers. The initial survey indicated that the affected trees were killed by the southern pine beetle (Dendroctonus frontalis Zimm.). This insect is not normally successful at colonizing these tree species because the trees produce large amounts of oleoresin that exclude the boring beetles. Subsequent investigations revealed that long-term acid deposition may have altered red spruce forest structure and function. There is some evidence that elevated acid deposition (particularly nitrogen) reduced tree water uptake potential, oleoresin production, and caused the trees to become more susceptible to insect colonization during the drought period. While the ecosystem was not in exceedance of the CAL, long-term nitrogen deposition pre-disposed the forest to other ecological stress. In combination, insects, drought, and nitrogen ultimately combined to cause the observed forest mortality. If any one of these factors were not present, the trees would likely not have died. This paper presents a conceptual framework of the ecosystem consequences of these interactions as well as limited plot level data to support this concept. Future assessments of the use of CAL studies need to account for multiple stress impacts to better understand ecosystem response. Published by Elsevier Ltd.
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E. Paoletti; M. Schaub; R. Matyssek; G. Wieser; A. Augustaitis; A. M. Bastrup-Birk; A. Bytnerowicz; M. S. Gunthardt-Goerg; G. Muller-Starck; Y. Serengil
2010-01-01
Over the past 20 years, the focus of forest science on air pollution has moved from forest decline to a holistic framework of forest health, and from the effects on forest production to the ecosystem services provided by forest ecosystems. Hence, future research should focus on the interacting factorial impacts and resulting antagonistic and synergistic responses of...
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Mangrove ecosystems under climate change
Jennerjahn, T.C.; Gilman, E.; Krauss, Ken W.; Lacerda, L.D.; Nordhaus, I.; Wolanski, E.
2017-01-01
This chapter assesses the response of mangrove ecosystems to possible outcomes of climate change, with regard to the following categories: (i) distribution, diversity, and community composition, (ii) physiology of flora and fauna, (iii) water budget, (iv) productivity and remineralization, (v) carbon storage in biomass and sediments, and (vi) the filter function for elements beneficial or harmful to life. These categories are then used to identify the regions most vulnerable to climate change. The four most important factors determining the response of mangrove ecosystems to climate change are sea level rise, an increase in frequency and/or intensity of storms, increases in temperature, and aridity. While these changes may be beneficial for some mangrove forests at latitudinal distribution limits, they will threaten forest structure and functions and related ecosystem services in most cases. The interaction of climate change with human interventions is discussed, as well as the effects on ecosystem services including possible adaptation and management options. The chapter closes with an outlook on knowledge gaps and priority research needed to fill these gaps.
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Long-term disturbance dynamics and resilience of tropical peat swamp forests
Cole, Lydia E S; Bhagwat, Shonil A; Willis, Katherine J
2015-01-01
1. The coastal peat swamp forests of Sarawak, Malaysian Borneo, are undergoing rapid conversion, predominantly into oil palm plantations. This wetland ecosystem is assumed to have experienced insignificant disturbance in the past, persisting under a single ecologically-stable regime. However, there is limited knowledge of the past disturbance regime, long-term functioning and fundamentally the resilience of this ecosystem to changing natural and anthropogenic perturbations through time. 2. In this study, long-term ecological data sets from three degraded peatlands in Sarawak were collected to shed light on peat swamp forest dynamics. Fossil pollen and charcoal were counted in each sedimentary sequence to reconstruct vegetation and investigate responses to past environmental disturbance, both natural and anthropogenic. 3. Results demonstrate that peat swamp forest taxa have dominated these vegetation profiles throughout the last c. 2000-year period despite the presence of various drivers of disturbance. Evidence for episodes of climatic variability, predominantly linked to ENSO events, and wildfires is present throughout. However, in the last c. 500 years, burning and indicators of human disturbance have elevated beyond past levels at these sites, concurrent with a reduction in peat swamp forest pollen. 4. Two key insights have been gained through this palaeoecological analysis: (i) peat swamp forest vegetation has demonstrated resilience to disturbance caused by burning and climatic variability in Sarawak in the late Holocene, however (ii) coincident with increased fire combined with human impact c. 500 years ago, these communities started to decline. 5. Synthesis. Sarawak's coastal peat swamps have demonstrated resilience to past natural disturbances, with forest vegetation persisting through episodes of fire and climatic variability. However, palaeoecological data presented here suggest that recent, anthropogenic disturbances are of a greater magnitude, causing the observed decline in the peat swamp forest communities in the last c. 500 years and challenging the ecosystem's persistence. This study greatly extends our knowledge of the ecological functioning of these understudied ecosystems, providing baseline information on the past vegetation and its response to disturbance. This understanding is central to developing management strategies that foster resilience in the remaining peat swamp forests and ensure continued provision of services, namely carbon storage, from this globally important ecosystem. PMID:26120202
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Long-term disturbance dynamics and resilience of tropical peat swamp forests.
Cole, Lydia E S; Bhagwat, Shonil A; Willis, Katherine J
2015-01-01
1. The coastal peat swamp forests of Sarawak, Malaysian Borneo, are undergoing rapid conversion, predominantly into oil palm plantations. This wetland ecosystem is assumed to have experienced insignificant disturbance in the past, persisting under a single ecologically-stable regime. However, there is limited knowledge of the past disturbance regime, long-term functioning and fundamentally the resilience of this ecosystem to changing natural and anthropogenic perturbations through time. 2. In this study, long-term ecological data sets from three degraded peatlands in Sarawak were collected to shed light on peat swamp forest dynamics. Fossil pollen and charcoal were counted in each sedimentary sequence to reconstruct vegetation and investigate responses to past environmental disturbance, both natural and anthropogenic. 3. Results demonstrate that peat swamp forest taxa have dominated these vegetation profiles throughout the last c . 2000-year period despite the presence of various drivers of disturbance. Evidence for episodes of climatic variability, predominantly linked to ENSO events, and wildfires is present throughout. However, in the last c . 500 years, burning and indicators of human disturbance have elevated beyond past levels at these sites, concurrent with a reduction in peat swamp forest pollen. 4. Two key insights have been gained through this palaeoecological analysis: (i) peat swamp forest vegetation has demonstrated resilience to disturbance caused by burning and climatic variability in Sarawak in the late Holocene, however (ii) coincident with increased fire combined with human impact c . 500 years ago, these communities started to decline. 5. Synthesis . Sarawak's coastal peat swamps have demonstrated resilience to past natural disturbances, with forest vegetation persisting through episodes of fire and climatic variability. However, palaeoecological data presented here suggest that recent, anthropogenic disturbances are of a greater magnitude, causing the observed decline in the peat swamp forest communities in the last c . 500 years and challenging the ecosystem's persistence. This study greatly extends our knowledge of the ecological functioning of these understudied ecosystems, providing baseline information on the past vegetation and its response to disturbance. This understanding is central to developing management strategies that foster resilience in the remaining peat swamp forests and ensure continued provision of services, namely carbon storage, from this globally important ecosystem.
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Bill Block
2012-01-01
As some of you might know, I am the new Editor-In-Chief for the Journal of Wildlife Management. Just to get acquainted, here are a few tidbits about me. I am the Program Manager for the Wildlife and Terrestrial Ecosystems Science Program with Rocky Mountain Research Station of the U.S. Forest Service. I consider myself a generalist having worked on reptiles, amphibians...
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The Hardwood Ecosystem Experiment: a framework for studying responses to forest management
Robert K. Swihart; Michael R. Saunders; Rebecca A. Kalb; G. Scott Haulton; Charles H., eds. Michler
2013-01-01
Conditions in forested ecosystems of southern Indiana are described before initiation of silvicultural treatments for the Hardwood Ecosystem Experiment (HEE). The HEE is a 100-year study begun in 2006 in Morgan-Monroe and Yellowwood State Forests to improve the sustainability of forest resources and quality of life of Indiana residents by understanding ecosystem and...
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Chang, Junning; Symes, William S; Lim, Felix; Carrasco, L Roman
2016-05-01
Despite the large implications of the use of tropical land for exports ("land absorption") on ecosystem services (ES) and global biodiversity conservation, the magnitude of these externalities is not known. We quantify the net value of ES lost in tropical countries as a result of cropland, forestland and pastureland absorption for exports after deducting ES gains through imports ("land displacement"). We find that net ES gains occur only in 7 out of the 41 countries and regions considered. We estimate global annual net losses of over 1.7 x 10(12) international dollars (I$) (I$1.1 x 10(12) if carbon-related services are not considered). After deducting the benefits from agricultural, forest and livestock rents in land replacing tropical forests, the net annual losses are I$1.3 and I$0.7 x 10(12), respectively. The results highlight the large magnitude of tropical ES losses through international trade that are not compensated by the rents of land uses in absorbed land.
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Matyssek, R; Wieser, G; Calfapietra, C; de Vries, W; Dizengremel, P; Ernst, D; Jolivet, Y; Mikkelsen, T N; Mohren, G M J; Le Thiec, D; Tuovinen, J-P; Weatherall, A; Paoletti, E
2012-01-01
Forests in Europe face significant changes in climate, which in interaction with air quality changes, may significantly affect forest productivity, stand composition and carbon sequestration in both vegetation and soils. Identified knowledge gaps and research needs include: (i) interaction between changes in air quality (trace gas concentrations), climate and other site factors on forest ecosystem response, (ii) significance of biotic processes in system response, (iii) tools for mechanistic and diagnostic understanding and upscaling, and (iv) the need for unifying modelling and empirical research for synthesis. This position paper highlights the above focuses, including the global dimension of air pollution as part of climate change and the need for knowledge transfer to enable reliable risk assessment. A new type of research site in forest ecosystems ("supersites") will be conducive to addressing these gaps by enabling integration of experimentation and modelling within the soil-plant-atmosphere interface, as well as further model development. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Northern Forest Ecosystem Dynamics Using Coupled Models and Remote Sensing
NASA Technical Reports Server (NTRS)
Ranson, K. J.; Sun, G.; Knox, R. G.; Levine, E. R.; Weishampel, J. F.; Fifer, S. T.
1999-01-01
Forest ecosystem dynamics modeling, remote sensing data analysis, and a geographical information system (GIS) were used together to determine the possible growth and development of a northern forest in Maine, USA. Field measurements and airborne synthetic aperture radar (SAR) data were used to produce maps of forest cover type and above ground biomass. These forest attribute maps, along with a conventional soils map, were used to identify the initial conditions for forest ecosystem model simulations. Using this information along with ecosystem model results enabled the development of predictive maps of forest development. The results obtained were consistent with observed forest conditions and expected successional trajectories. The study demonstrated that ecosystem models might be used in a spatial context when parameterized and used with georeferenced data sets.
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Wang, Shaoqiang; Zhou, Lei; Chen, Jingming; Ju, Weimin; Feng, Xianfeng; Wu, Weixing
2011-06-01
Affected by natural and anthropogenic disturbances such as forest fires, insect-induced mortality and harvesting, forest stand age plays an important role in determining the distribution of carbon pools and fluxes in a variety of forest ecosystems. An improved understanding of the relationship between net primary productivity (NPP) and stand age (i.e., age-related increase and decline in forest productivity) is essential for the simulation and prediction of the global carbon cycle at annual, decadal, centurial, or even longer temporal scales. In this paper, we developed functions describing the relationship between national mean NPP and stand age using stand age information derived from forest inventory data and NPP simulated by the BEPS (Boreal Ecosystem Productivity Simulator) model in 2001. Due to differences in ecobiophysical characteristics of different forest types, NPP-age equations were developed for five typical forest ecosystems in China (deciduous needleleaf forest (DNF), evergreen needleleaf forest in tropic and subtropical zones (ENF-S), deciduous broadleaf forest (DBF), evergreen broadleaf forest (EBF), and mixed broadleaf forest (MBF)). For DNF, ENF-S, EBF, and MBF, changes in NPP with age were well fitted with a common non-linear function, with R(2) values equal to 0.90, 0.75, 0.66, and 0.67, respectively. In contrast, a second order polynomial was best suitable for simulating the change of NPP for DBF, with an R(2) value of 0.79. The timing and magnitude of the maximum NPP varied with forest types. DNF, EBF, and MBF reached the peak NPP at the age of 54, 40, and 32 years, respectively, while the NPP of ENF-S maximizes at the age of 13 years. The highest NPP of DBF appeared at 122 years. NPP was generally lower in older stands with the exception of DBF, and this particular finding runs counter to the paradigm of age-related decline in forest growth. Evaluation based on measurements of NPP and stand age at the plot-level demonstrates the reliability and applicability of the fitted NPP-age relationships. These relationships were used to replace the normalized NPP-age relationship used in the original InTEC (Integrated Terrestrial Ecosystem Carbon) model, to improve the accuracy of estimated carbon balance for China's forest ecosystems. With the revised NPP-age relationship, the InTEC model simulated a larger carbon source from 1950-1980 and a larger carbon sink from 1985-2001 for China's forests than the original InTEC model did because of the modification to the age-related carbon dynamics in forests. This finding confirms the importance of considering the dynamics of NPP related to forest age in estimating regional and global terrestrial carbon budgets. Copyright © 2011 Elsevier Ltd. All rights reserved.
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[A review on disturbance ecology of forest].
Zhu, Jiaojun; Liu, Zugen
2004-10-01
More than 80% of terrestrial ecosystems have been influenced by natural disasters, human activities and the combination of both natural and human disturbances. Forest ecosystem, as one of the most important terrestrial ecosystems, has also been disturbed without exception. Under the disturbance from natural disasters and human activities, particularly from the unreasonable activities of human beings, forest decline or forest degradation has become more and more severe. For this reason, sustaining or recovering forest service functions is one of the current purposes for managing forest ecosystems. In recent decades, the studies on disturbed ecosystems have been carried out frequently, especially on their ecological processes and their responses to the disturbances. These studies play a very important role in the projects of natural forest conservation and the construction of ecological environment in China. Based on a wide range of literatures collection on forest disturbance research, this paper discussed the fundamental concepts of disturbance ecology, the relationships between forest management and disturbance, and the study contents of forest disturbance ecology. The major research topics of forest disturbance ecology may include: 1) the basic characteristics of disturbed forests; 2) the processes of natural and human disturbances; 3) the responses of forests ecosystem to the disturbances; 4) the main ecological processes or the consequential results of disturbed forests, including the change of biodiversity, soil nutrient and water cycle, eco-physiology and carbon cycle, regeneration mechanism of disturbed forests and so on; 5) the relationships between disturbances and forest management; and 6) the principles and techniques for the management of disturbed forests. This review may be helpful to the management of disturbed forest ecosystem, and to the projects of natural forest conservation in China.
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Fierro, Pablo; Bertrán, Carlos; Tapia, Jaime; Hauenstein, Enrique; Peña-Cortés, Fernando; Vergara, Carolina; Cerna, Cindy; Vargas-Chacoff, Luis
2017-12-31
Land-use change is a principal factor affecting riparian vegetation and river biodiversity. In Chile, land-use change has drastically intensified over the last decade, with native forests converted to exotic forest plantations and agricultural land. However, the effects thereof on aquatic ecosystems are not well understood. Closing this knowledge gap first requires understanding how human perturbations affect riparian and stream biota. Identified biological indicators could then be applied to determine the health of fluvial ecosystems. Therefore, this study investigated the effects of land-use change on the health of riparian and aquatic ecosystems by assessing riparian vegetation, water quality, benthic macroinvertebrate assemblages, and functional feeding groups. Twenty-one sites in catchment areas with different land-uses (i.e. pristine forests, native forests, exotic forest plantations, and agricultural land) were selected and sampled during the 2010 to 2012 dry seasons. Riparian vegetation quality was highest in pristine forests. Per the modified Macroinvertebrate Family Biotic Index for Chilean species, the best conditions existed in native forests and the worst in agricultural catchments. Water quality and macroinvertebrate assemblages significantly varied across land-use areas, with forest plantations and agricultural land having high nutrient concentrations, conductivity, suspended solids, and apparent color. Macroinvertebrate assemblage diversity was lowest for agricultural and exotic forest plantation catchments, with notable non-insect representation. Collector-gatherers were the most abundant functional feeding group, suggesting importance independent of land-use. Land-use areas showed no significant differences in functional feeding groups. In conclusion, anthropogenic land-use changes were detectable through riparian quality, water quality, and macroinvertebrate assemblages, but not through functional feeding groups. These data, particularly the riparian vegetation and macroinvertebrate assemblage parameters, could be applied towards the conservation and management of riparian ecosystems through land-use change studies. Copyright © 2017 Elsevier B.V. All rights reserved.
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Beier, Colin M; Caputo, Jesse; Groffman, Peter M
2015-10-01
In this study, by coupling long-term ecological data with empirical proxies of societal demand for benefits, we measured the capacity of forest watersheds to provide ecosystem services over variable time periods, to different beneficiaries, and in response to discrete perturbations and drivers of change. We revisited one of the earliest ecosystem experiments in North America: the 1963 de-vegetation of a forested catchment at Hubbard Brook Experimental Forest in New Hampshire, USA. Potential benefits of the regulation of water flow, water quality, greenhouse gases, and forest growth were compared between experimental (WS 2) and reference (WS 6) watersheds over a 30-year period. Both watersheds exhibited similarly high capacity for flow regulation, in part because functional loads remained low (i.e., few major storm events) during the de-vegetation period. Drought mitigation capacity, or the maintenance of flows sufficient to satisfy municipal water consumption, was higher in WS 2 due to reduced evapotranspiration associated with loss of plant cover. We also assessed watershed capacity to regulate flows to satisfy different beneficiaries, including hypothetical flood averse and drought averse types. Capacity to regulate water quality was severely degraded during de-vegetation, as nitrate concentrations exceeded drinking water standards on 40% of measurement days. Once forest regeneration began, WS 2 rapidly recovered the capacity to provide safe drinking water, and subsequently mitigated the eutrophication potential of rainwater at a marginally higher level than WS 6. We estimated this additional pollution removal benefit would have to accrue for approximately 65-70 years to offset the net eutrophication cost incurred during forest removal. Overall, our results affirmed the critical role of forest vegetation in water regulation, but also indicated trade-offs associated with forest removal and recovery that partially depend on larger-scale exogenous changes in climate forcing and pollution inputs. We also provide a starting point for integrating long-term ecological research and modeling data into ecosystem services science.
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[Evaluation of economic forest ecosystem services in China].
Wang, Bing; Lu, Shao-Wei
2009-02-01
This paper quantitatively evaluated the economic forest ecosystem services in the provinces of China in 2003, based on the long-term and continuous observations of economic forest ecosystems in this country, the sixth China national forest resources inventory data, and the price parameter data from the authorities in the world, and by applying the law of market value, the method of substitution of the expenses, and the law of the shadow project. The results showed that in 2003, the total value of economic forest ecosystem services in China was 11763.39 x 10(8) yuan, and the total value of the products from economic forests occupied 19.3% of the total ecosystem services value, which indicated that the economic forests not only provided society direct products, but also exhibited enormous eco-economic value. The service value of the functions of economic forests was in the order of water storage > C fixation and O2 release > biodiversity conservation > erosion control > air quality purification > nutrient cycle. The spatial pattern of economic forest ecosystem services in the provinces of China had the same trend with the spatial distribution of water and heat resources and biodiversity. To understand the differences of economic forest ecosystem services in the provinces of China was of significance in alternating the irrational arrangement of our present forestry production, diminishing the abuses of forest management, and establishing high grade, high efficient, and modernized economic forests.
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Management Mangrove Experiences Form Coastal People
NASA Astrophysics Data System (ADS)
Indah, P. N.; Radianto, I.; Abidin, Z.; Amir, I. T.; Pribadi, D. U.
2018-01-01
The mangrove area has an important meaning in beach ecosystem, both from ecological and economical aspects. For this, the rehabilitation of mangrove forest is done as one effort that aims to maintain and return the mangrove forest function as one of life system supporters, especially in beach area. The most respondent ages of coast people of Gending, Pajarakan, dan Kraksaan districts, Probolinggo Regency are between 30 to 59 years old, i.e. as 86 people or 95.55% indicates that coast people are productive ages so they can be hoped very potential for having role in supporting mangrove ecosystem management of Probolinggo Regency coast. The average respondent educational rates are mostly Elementary School to Senior High School, i.e. as 76 people. Generally, human resources of coast people have relatively good education level. Thereby, it can be hoped to have positive potencies for the role of coast people themselves toward the mangrove ecosystem management support of Probolinggo Regency coast. The average most respondents have family burdens two and three people as six people or 6.67 percent. But, there are still three respondents who have not have family burdens. Generally, more and more members help in respondent’s jobs. The mangrove ecosystem management strategy of Probolinggo Regency coast is by involving people role (people and people figures) and governmental supports through the models of mangrove forest management strategy, the model of embankment cultivation management by entering mangrove as input resources of production facilities, and ecotourism management by the purpose of improving people income.
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Patricia R. Butler; Louis Iverson; Frank R. Thompson; Leslie Brandt; Stephen Handler; Maria Janowiak; P. Danielle Shannon; Chris Swanston; Kent Karriker; Jarel Bartig; Stephanie Connolly; William Dijak; Scott Bearer; Steve Blatt; Andrea Brandon; Elizabeth Byers; Cheryl Coon; Tim Culbreth; Jad Daly; Wade Dorsey; David Ede; Chris Euler; Neil Gillies; David M. Hix; Catherine Johnson; Latasha Lyte; Stephen Matthews; Dawn McCarthy; Dave Minney; Daniel Murphy; Claire O’Dea; Rachel Orwan; Matthew Peters; Anantha Prasad; Cotton Randall; Jason Reed; Cynthia Sandeno; Tom Schuler; Lesley Sneddon; Bill Stanley; Al Steele; Susan Stout; Randy Swaty; Jason Teets; Tim Tomon; Jim Vanderhorst; John Whatley; Nicholas Zegre
2015-01-01
Forest ecosystems in the Central Appalachians will be affected directly and indirectly by a changing climate over the 21st century. This assessment evaluates the vulnerability of forest ecosystems in the Central Appalachian Broadleaf Forest-Coniferous Forest-Meadow and Eastern Broadleaf Forest Provinces of Ohio, West Virginia, and Maryland for a range of future...
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Contribution of stumps to carbon and nitrogen pools in southern Appalachian hardwood forests
Eric B. Sucre; Thomas R. Fox
2008-01-01
Decomposing stumps are prevalent in managed forest ecosystems although the impact of these microsites on nutrient retention and cycling is relatively unknown. In this study, stumps were defined as the aboveground and belowground (i.e., root system) left over from previous harvests. The objective of this study was to quantify the total soil volume occupied by stumps and...
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Historic and Contemporary Land Use in Southwestern Grassland Ecosystems
Carol Raish
2004-01-01
This chapter encompasses the lands of the Southwest as defined by Region 3 of the USDA Forest Service (USFS): Arizona, New Mexico, and portions of western Oklahoma and the Texas Panhandle. I examine human use and modification of the grasslands/rangelands of this region, with an emphasis on those areas managed by the Forest Service. Because the majority of publications...
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Analyzing canopy structure in Pacific Northwest old-growth forests with a stand-scale crown model
Robert Van Pelt; Malcolm P. North
1996-01-01
I n forests, the canopy is the locale of critical ecosystem processes such as photosynthesis and evapotranspiration. and it provides essential habitat for a highly diverse array of animals, plants, and other organisms. Despite its importance, the structure of the canopy as a whole has had little quantitative study because limited access makes quantification difficult...
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NASA Astrophysics Data System (ADS)
Campo, Julio
2016-09-01
The effect of precipitation regime on N and P cycles in tropical forests is poorly understood, despite global climate models project total precipitation reductions during the 21st Century. I investigated the influence of variation in annual precipitation (1240-642 mm yr-1) on N and P intra-system cycling along a precipitation regime gradient at Yucatan including 12 mature, tropical dry forests (TDFs) growing under otherwise similar conditions (similar annual temperature, rainfall seasonality and geological substrate). I analyzed N and P storage and turnover in the forest floor and mineral soil and explored the dependence of these processes and pools on precipitation level. The study findings indicate that with decreasing precipitation the litterfall decreases slightly (10%), while nutrient use efficiency increases by 20% for N, and by 40% for P. Decomposition rate and nutrient release was smallest in the dry extremity of precipitation regime. The difference between N and P turnover times in the forest floor and in organic matter indicates that different nutrients control the ecosystem function across the precipitation gradient. The data from this study reveals a pattern of limitation shifting from P towards N with decreasing annual precipitation. I suggest that the long-term consequences of the expected decrease in precipitation in many tropical dry regions would changes N and P supply could have long-term negative effects on primary productivity and future carbon storage in TDFs.
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Forest ecosystems: Vegetation, disturbance, and economics: Chapter 5
Littell, Jeremy S.; Hicke, Jeffrey A.; Shafer, Sarah L.; Capalbo, Susan M.; Houston, Laurie L.; Glick, Patty
2013-01-01
Forests cover about 47% of the Northwest (NW–Washington, Oregon, and Idaho) (Smith et al. 2009, fig. 5.1, table 5.1). The impacts of current and future climate change on NW forest ecosystems are a product of the sensitivities of ecosystem processes to climate and the degree to which humans depend on and interact with those systems. Forest ecosystem structure and function, particularly in relatively unmanaged forests where timber harvest and other land use have smaller effects, is sensitive to climate change because climate has a strong influence on ecosystem processes. Climate can affect forest structure directly through its control of plan physiology and life history (establishment, individual growth, productivity, and morality) or indirectly through its control of disturbance (fire, insects, disease). As climate changes, many forest processes will be affected, altering ecosystem services such as timber production and recreation. These changes have socioeconomic implications (e.g. for timber economies) and will require changes to current management of forests. Climate and management will interact to determine the forests of the future, and the scientific basis for adaptation to climate change in forests thus depends significantly on how forests will be affected.
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Acid Precipitation and the Forest Ecosystem
ERIC Educational Resources Information Center
Dochinger, Leon S.; Seliga, Thomas A.
1975-01-01
The First International Symposium on Acid Precipitation and the Forest Ecosystem dealt with the potential magnitude of the global effects of acid precipitation on aquatic ecosystems, forest soils, and forest vegetation. The problem is discussed in the light of atmospheric chemistry, transport, and precipitation. (Author/BT)
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Assessment and valuation of forest ecosystem services: State of the science review
Seth Binder; Robert G. Haight; Stephen Polasky; Travis Warziniack; Miranda H. Mockrin; Robert L. Deal; Greg Arthaud
2017-01-01
This review focuses on the assessment and economic valuation of ecosystem services from forest ecosystemsâthat is, our ability to predict changes in the quantity and value of ecosystem services as a result of specific forest management decisions. It is aimed at forest economists and managers and intended to provide a useful reference to those interested in developing...
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Successional dynamics drive tropical forest nutrient limitation
NASA Astrophysics Data System (ADS)
Chou, C.; Hedin, L. O. O.
2017-12-01
It is increasingly recognized that nutrients such as N and P may significantly constrain the land carbon sink. However, we currently lack a complete understanding of these nutrient cycles in forest ecosystems and how to incorporate them into Earth System Models. We have developed a framework of dynamic forest nutrient limitation, focusing on the role of secondary forest succession and canopy gap disturbances as bottlenecks of high plant nutrient demand and limitation. We used succession biomass data to parameterize a simple ecosystem model and examined the dynamics of nutrient limitation throughout tropical secondary forest succession. Due to the patterns of biomass recovery in secondary tropical forests, we found high nutrient demand from rapid biomass accumulation in the earliest years of succession. Depending on previous land use scenarios, soil nutrient availability may also be low in this time period. Coupled together, this is evidence that there may be high biomass nutrient limitation early in succession, which is partially met by abundant symbiotic nitrogen fixation from certain tree species. We predict a switch from nitrogen limitation in early succession to one of three conditions: (i) phosphorus only, (ii) phosphorus plus nitrogen, or (iii) phosphorus, nitrogen, plus light co-limitation. We will discuss the mechanisms that govern the exact trajectory of limitation as forests build biomass. In addition, we used our model to explore scenarios of tropical secondary forest impermanence and the impacts of these dynamics on ecosystem nutrient limitation. We found that secondary forest impermanence exacerbates nutrient limitation and the need for nitrogen fixation early in succession. Together, these results indicate that biomass recovery dynamics early in succession as well as their connection to nutrient demand and limitation are fundamental for understanding and modeling nutrient limitation of the tropical forest carbon sink.
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NASA Astrophysics Data System (ADS)
Hirata, R.; Ito, A.; Saigusa, N.
2013-12-01
Carbon balance in a forest ecosystem can be quite variable if the forest ecosystem structure and function change abruptly as a result of disturbance and subsequent recovery processes. A map of forest age is useful for upscaling carbon balance from the site level to a regional scale because it provides information about when disturbance occurred and how it spread over a wide area. In this study, we used maps of forest age to help evaluate spatial and temporal variations in the carbon balance of forest ecosystems with a process-based ecosystem model. Forests less than 60 years old account for more than 70% of Japanese forests because forest stands have been quickly replaced after disturbance caused by thinning, harvesting, plantations, fires, typhoons, and insect damage. However, few studies have attempted to quantify how much disturbance affects the spatial and temporal variations of carbon balance. In this study, we focused on how disturbance and subsequent re-growth affected the spatial and temporal variations of the carbon balance of forests. We adapted the Vegetation Integrative SImulator for Trace Gases (VISIT) model in order to simulate carbon balance on Hokkaido, which is the northernmost island of Japan. The model was validated with tower flux data obtained from forests with ages between 0 and 43 years. Simulations of the carbon balance were conducted for the period 1948-2010 after a 1000-year spin-up at a spatial resolution of 1 km × 1 km. We investigated two case studies of simulated carbon balance: one that took into account the spatial distribution of forest ages derived from forest inventory data, and another that ignored the impact of disturbance (i.e., no disturbance and a homogeneous distribution of ages). We first focused on the difference from 2000-2010 in the spatial distribution of net ecosystem production (NEP) between the disturbance and non-disturbance cases. In the non-disturbance case, the temporal and spatial changes in NEP were gradual and ranged from 0 to 1 t C ha-1 y-1, depending on meteorological conditions such as temperature or solar radiation. In the disturbance case, however, large NEP changes ranging from 3 to 5 t C ha-1 y-1 were distributed in patches like hotspots, because the forests in those spots ranged in age from 20 to 100 years and were younger than the forests in the non-disturbance case. In the 1970s, wood harvesting and tree planting were conducted intensively on Hokkaido. In the disturbance case during this period, there were many hotspots where NEP was negative. We next focused on the difference between the disturbance and non-disturbance cases of temporal variations of spatially averaged NEP on Hokkaido. Until 1970, the difference between the two cases of average NEP was less than 0.01 t C ha-1 y-1. After 1970, the difference became large and reached about 0.5 t C ha-1 y-1, the implication being that the regional NEP in the disturbance case increased to as much as 2-5 times the regional NEP of the non-disturbance case. Our results show the importance of considering forest age when simulating the carbon balance of forests. Carbon balance maps that take forest age into account are useful for carbon management and prediction of ecosystem feedbacks on climate change.
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The 1990 forest ecosystem dynamics multisensor aircraft campaign
NASA Technical Reports Server (NTRS)
Williams, Darrel L.; Ranson, K. Jon
1991-01-01
The overall objective of the Forest Ecosystem Dynamics (FED) research activity is to develop a better understanding of the dynamics of forest ecosystem evolution over a variety of temporal and spatial scales. Primary emphasis is being placed on assessing the ecosystem dynamics associated with the transition zone between northern hardwood forests in eastern North America and the predominantly coniferous forests of the more northerly boreal biome. The approach is to combine ground-based, airborne, and satellite observations with an integrated forest pattern and process model which is being developed to link together existing models of forest growth and development, soil processes, and radiative transfer.
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Sicard, Pierre; Augustaitis, Algirdas; Belyazid, Salim; Calfapietra, Carlo; de Marco, Alessandra; Fenn, Mark; Bytnerowicz, Andrzej; Grulke, Nancy; He, Shang; Matyssek, Rainer; Serengil, Yusuf; Wieser, Gerhard; Paoletti, Elena
2016-06-01
Research directions from the 27th conference for Specialists in Air Pollution and Climate Change Effects on Forest Ecosystems (2015) reflect knowledge advancements about (i) Mechanistic bases of tree responses to multiple climate and pollution stressors, in particular the interaction of ozone (O3) with nitrogen (N) deposition and drought; (ii) Linking genetic control with physiological whole-tree activity; (iii) Epigenetic responses to climate change and air pollution; (iv) Embedding individual tree performance into the multi-factorial stand-level interaction network; (v) Interactions of biogenic and anthropogenic volatile compounds (molecular, functional and ecological bases); (vi) Estimating the potential for carbon/pollution mitigation and cost effectiveness of urban and peri-urban forests; (vii) Selection of trees adapted to the urban environment; (viii) Trophic, competitive and host/parasite relationships under changing pollution and climate; (ix) Atmosphere-biosphere-pedosphere interactions as affected by anthropospheric changes; (x) Statistical analyses for epidemiological investigations; (xi) Use of monitoring for the validation of models; (xii) Holistic view for linking the climate, carbon, N and O3 modelling; (xiii) Inclusion of multiple environmental stresses (biotic and abiotic) in critical load determinations; (xiv) Ecological impacts of N deposition in the under-investigated areas; (xv) Empirical models for mechanistic effects at the local scale; (xvi) Broad-scale N and sulphur deposition input and their effects on forest ecosystem services; (xvii) Measurements of dry deposition of N; (xviii) Assessment of evapotranspiration; (xix) Remote sensing assessment of hydrological parameters; and (xx) Forest management for maximizing water provision and overall forest ecosystem services. Ground-level O3 is still the phytotoxic air pollutant of major concern to forest health. Specific issues about O3 are: (xxi) Developing dose-response relationships and stomatal O3 flux parameterizations for risk assessment, especially, in under-investigated regions; (xxii) Defining biologically based O3 standards for protection thresholds and critical levels; (xxiii) Use of free-air exposure facilities; (xxiv) Assessing O3 impacts on forest ecosystem services. Copyright © 2016 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Loustau, D.; Moreaux, V.; Bosc, A.; Trichet, P.; Kumari, J.; Rabemanantsoa, T.; Balesdent, J.; Jolivet, C.; Medlyn, B. E.; Cavaignac, S.; Nguyen-The, N.
2012-12-01
For predicting the future of the forest carbon cycle in forest ecosystems, it is necessary to account for both the climate and management impacts. Climate effects are significant not only at a short time scale but also at the temporal horizon of a forest life cycle e.g. through shift in atmospheric CO2 concentration, temperature and precipitation regimes induced by the enhanced greenhouse effect. Intensification of forest management concerns an increasing fraction of temperate and tropical forests and untouched forests represents only one third of the present forest area. Predicting tools are therefore needed to project climate and management impacts over the forest life cycle and understand the consequence of management on the forest ecosystem carbon cycle. This communication summarizes the structure, main components and properties of a carbon transfer model that describes the processes controlling the carbon cycle of managed forest ecosystems. The model, GO+, links three main components, (i) a module describing the vegetation-atmosphere mass and energy exchanges in 3D, (ii) a plant growth module and a (iii) soil carbon dynamics module in a consistent carbon scheme of transfer from atmosphere back into the atmosphere. It was calibrated and evaluated using observed data collected on coniferous and broadleaved forest stands. The model predicts the soil, water and energy balance of entire rotations of managed stands from the plantation to the final cut and according to a range of management alternatives. It accounts for the main soil and vegetation management operations such as soil preparation, understorey removal, thinnings and clearcutting. Including the available knowledge on the climatic sensitivity of biophysical and biogeochemical processes involved in atmospheric exchanges and carbon cycle of forest ecosystems, GO+ can produce long-term backward or forward simulations of forest carbon and water cycles under a range of climate and management scenarios. This model applications to the prediction and analysis of climate scenarios impacts on southwestern European forests underlines the role of management alternatives, precipitation regime, CO2 concentration and atmospheric humidity .Frequency of soil preparation operations and understorey management play a major role in controlling the net carbon flux into the atmosphere at the juvenile stage ( 0 to 10 y-old) whereas climate and rotation duration control the functioning of adult phase. The model predicts that a drier and warmer climate will reduce the forest productivity and deplete soil and carbon stocks in managed forest from Southwestern Europe within decades, such effects being amplified for most intensive management alternatives. This work was part of the European research project GHG-Europe (EU contract No. 244122) and the French national project FAST co-funded by the Ecology, Agriculture and Forestry Ministries and the Region Aquitaine.
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Dynamics of novel forests of Castilla elastica in Puerto Rico: from species to ecosystems.
Fonseca da Silva, Jéssica
2015-08-01
Novel forests (NFs)-forests that contain a combination of introduced and native species-are a consequence of intense anthropogenic disturbances and the natural resilience of disturbed ecosystems. The extent to which NFs have similar forest function as comparable native secondary forests is a matter of debate in the scientific community. Little is known about the performance of individual species in those forests. This study focuses on the functional attributes of Castilla elastica NFs in Puerto Rico and on the differences between introduced and native species growing side by side in these forests. Rates of processes measured here were later compared with data from literature about NSFs. I hypothesize that juvenile plants of C. elastica in NFs have higher survival rate than those of native species and that C. elastica trees have faster biomass fluxes than native trees. To test the hypotheses, I measured survival rates of juvenile plants and tree growth and characterized the aboveground litter fluxes and storage. Although juvenile plants of native species displayed higher survival rates than those of C. elastica (53% vs. 28%), the latter was dominant in the understory (96%). Stand biomass growth rate was 2.0 ± 0.4 (average ± one standard deviation) Mg·ha(-1)·year(-1) for the whole forest, and Guarea guidonia, a native species, exhibited the highest tree growth. Total litter fall was 9.6 ± 0.5 Mg·ha(-1)·year(-1), and mean litter standing stock was 4.4 ± 0.1 Mg·ha(-1). Castilla elastica litter fall decomposed twice as fast as that of native species (5.8 ± 1.1 vs. 3.03 ± 1 k·year(-1)). Literature comparisons show that the present NFs differ in some rates of processes from NSFs. This study brings unique and detailed supporting data about the ecological dynamics under mature novel forest stands. Further comprehensive studies about NFs are important to strengthen the body of knowledge about the wide range of variation of emerging tropical ecosystems. Due to the large increase in the area covered by NFs, greater attention is needed to understand their functioning, delivery of ecological services and management requirements.
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Ma, Jianyong; Shugart, Herman H; Yan, Xiaodong; Cao, Cougui; Wu, Shuang; Fang, Jing
2017-05-15
The carbon budget of forest ecosystems, an important component of the terrestrial carbon cycle, needs to be accurately quantified and predicted by ecological models. As a preamble to apply the model to estimate global carbon uptake by forest ecosystems, we used the CO 2 flux measurements from 37 forest eddy-covariance sites to examine the individual tree-based FORCCHN model's performance globally. In these initial tests, the FORCCHN model simulated gross primary production (GPP), ecosystem respiration (ER) and net ecosystem production (NEP) with correlations of 0.72, 0.70 and 0.53, respectively, across all forest biomes. The model underestimated GPP and slightly overestimated ER across most of the eddy-covariance sites. An underestimation of NEP arose primarily from the lower GPP estimates. Model performance was better in capturing both the temporal changes and magnitude of carbon fluxes in deciduous broadleaf forest than in evergreen broadleaf forest, and it performed less well for sites in Mediterranean climate. We then applied the model to estimate the carbon fluxes of forest ecosystems on global scale over 1982-2011. This application of FORCCHN gave a total GPP of 59.41±5.67 and an ER of 57.21±5.32PgCyr -1 for global forest ecosystems during 1982-2011. The forest ecosystems over this same period contributed a large carbon storage, with total NEP being 2.20±0.64PgCyr -1 . These values are comparable to and reinforce estimates reported in other studies. This analysis highlights individual tree-based model FORCCHN could be used to evaluate carbon fluxes of forest ecosystems on global scale. Copyright © 2017 Elsevier B.V. All rights reserved.
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Cryptic Methane Emissions from Upland Forest Ecosystems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Megonigal, Patrick; Pitz, Scott
This exploratory research on Cryptic Methane Emissions from Upland Forest Ecosystems was motivated by evidence that upland ecosystems emit 36% as much methane to the atmosphere as global wetlands, yet we knew almost nothing about this source. The long-term objective was to refine Earth system models by quantifying methane emissions from upland forests, and elucidate the biogeochemical processes that govern upland methane emissions. The immediate objectives of the grant were to: (i) test the emerging paradigm that upland trees unexpectedly transpire methane, (ii) test the basic biogeochemical assumptions of an existing global model of upland methane emissions, and (iii) developmore » the suite of biogeochemical approaches that will be needed to advance research on upland methane emissions. We instrumented a temperate forest system in order to explore the processes that govern upland methane emissions. We demonstrated that methane is emitted from the stems of dominant tree species in temperate upland forests. Tree emissions occurred throughout the growing season, while soils adjacent to the trees consumed methane simultaneously, challenging the concept that forests are uniform sinks of methane. High frequency measurements revealed diurnal cycling in the rate of methane emissions, pointing to soils as the methane source and transpiration as the most likely pathway for methane transport. We propose the forests are smaller methane sinks than previously estimated due to stem emissions. Stem emissions may be particularly important in upland tropical forests characterized by high rainfall and transpiration, resolving differences between models and measurements. The methods we used can be effectively implemented in order to determine if the phenomenon is widespread.« less
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Supplementing forest ecosystem health projects on the ground
Cathy Barbouletos; Lynette Z. Morelan
1995-01-01
Understanding the functions and processes of ecosystems is critical before implementing forest ecosystem health projects on the landscape. Silvicultural treatments such as thinning, prescribed fire, and reforestation can simulate disturbance regimes and landscape patterns that have regulated forest ecosystems for centuries. As land managers we need to understand these...
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Sustainable development and use of ecosystems with non-forest trees
USDA-ARS?s Scientific Manuscript database
Non-forest trees are components of managed ecosystems including orchards and agroforestry systems and natural ecosystems such as savannas and riparian corridors. Each of these ecosystems includes trees but does not have a complete tree canopy or spatial extent necessary to create a true forest ecosy...
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Impacts of forestry on boreal forests: An ecosystem services perspective.
Pohjanmies, Tähti; Triviño, María; Le Tortorec, Eric; Mazziotta, Adriano; Snäll, Tord; Mönkkönen, Mikko
2017-11-01
Forests are widely recognized as major providers of ecosystem services, including timber, other forest products, recreation, regulation of water, soil and air quality, and climate change mitigation. Extensive tracts of boreal forests are actively managed for timber production, but actions aimed at increasing timber yields also affect other forest functions and services. Here, we present an overview of the environmental impacts of forest management from the perspective of ecosystem services. We show how prevailing forestry practices may have substantial but diverse effects on the various ecosystem services provided by boreal forests. Several aspects of these processes remain poorly known and warrant a greater role in future studies, including the role of community structure. Conflicts among different interests related to boreal forests are most likely to occur, but the concept of ecosystem services may provide a useful framework for identifying and resolving these conflicts.
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i-Tree: Tools to assess and manage structure, function, and value of community forests
NASA Astrophysics Data System (ADS)
Hirabayashi, S.; Nowak, D.; Endreny, T. A.; Kroll, C.; Maco, S.
2011-12-01
Trees in urban communities can mitigate many adverse effects associated with anthropogenic activities and climate change (e.g. urban heat island, greenhouse gas, air pollution, and floods). To protect environmental and human health, managers need to make informed decisions regarding urban forest management practices. Here we present the i-Tree suite of software tools (www.itreetools.org) developed by the USDA Forest Service and their cooperators. This software suite can help urban forest managers assess and manage the structure, function, and value of urban tree populations regardless of community size or technical capacity. i-Tree is a state-of-the-art, peer-reviewed Windows GUI- or Web-based software that is freely available, supported, and continuously refined by the USDA Forest Service and their cooperators. Two major features of i-Tree are 1) to analyze current canopy structures and identify potential planting spots, and 2) to estimate the environmental benefits provided by the trees, such as carbon storage and sequestration, energy conservation, air pollution removal, and storm water reduction. To cover diverse forest topologies, various tools were developed within the i-Tree suite: i-Tree Design for points (individual trees), i-Tree Streets for lines (street trees), and i-Tree Eco, Vue, and Canopy (in the order of complexity) for areas (community trees). Once the forest structure is identified with these tools, ecosystem services provided by trees can be estimated with common models and protocols, and reports in the form of texts, charts, and figures are then created for users. Since i-Tree was developed with a client/server architecture, nationwide data in the US such as location-related parameters, weather, streamflow, and air pollution data are stored in the server and retrieved to a user's computer at run-time. Freely available remote-sensed images (e.g. NLCD and Google maps) are also employed to estimate tree canopy characteristics. As the demand for i-Tree grows internationally, environmental databases from more countries will be coupled with the software suite. Two more i-Tree applications, i-Tree Forecast and i-Tree Landscape are now under development. i-Tree Forecast simulates canopy structures for up to 100 years based on planting and mortality rates and adds capabilities for other i-Tree applications to estimate the benefits of future canopy scenarios. While most i-Tree applications employ a spatially lumped approach, i-Tree landscape employs a spatially distributed approach that allows users to map changes in canopy cover and ecosystem services through time and space. These new i-Tree tools provide an advanced platform for urban managers to assess the impact of current and future urban forests. i-Tree allows managers to promote effective urban forest management and sound arboricultural practices by providing information for advocacy and planning, baseline data for making informed decisions, and standardization for comparisons with other communities.
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Vasile A. Suchar; Nicholas L. Crookston
2010-01-01
The understory community is a critical component of many processes of forest ecosystems. Cover and biomass indices of shrubs and herbs of forested ecosystems of Northwestern United States are presented. Various forest data were recorded for 10,895 plots during a Current Vegetation Survey, over the National Forest lands of entire Pacific Northwest. No significant...
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Assessment of forest fuel loadings in Puerto Rico and the U.S. Virgin Islands
Thomas Brandeis; Christopher Woodall
2009-01-01
Quantification of the downed woody materials that comprise forest fuels has gained importance in Caribbean forest ecosystems due to the increasing incidence and severity of wildfires on island ecosystems. Because large-scale assessments of forest fuels have rarely been conducted for these ecosystems, forest fuels were assessed at 121 U.S. Department of Agriculture,...
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Petroleum hydrocarbon contamination in boreal forest soils: a mycorrhizal ecosystems perspective.
Robertson, Susan J; McGill, William B; Massicotte, Hugues B; Rutherford, P Michael
2007-05-01
The importance of developing multi-disciplinary approaches to solving problems relating to anthropogenic pollution is now clearly appreciated by the scientific community, and this is especially evident in boreal ecosystems exposed to escalating threats of petroleum hydrocarbon (PHC) contamination through expanded natural resource extraction activities. This review aims to synthesize information regarding the fate and behaviour of PHCs in boreal forest soils in both ecological and sustainable management contexts. From this, we hope to evaluate potential management strategies, identify gaps in knowledge and guide future research. Our central premise is that mycorrhizal systems, the ubiquitous root symbiotic fungi and associated food-web communities, occupy the structural and functional interface between decomposition and primary production in northern forest ecosystems (i.e. underpin survival and productivity of the ecosystem as a whole), and, as such, are an appropriate focal point for such a synthesis. We provide pertinent basic information about mycorrhizas, followed by insights into the ecology of ecto- and ericoid mycorrhizal systems. Next, we review the fate and behaviour of PHCs in forest soils, with an emphasis on interactions with mycorrhizal fungi and associated bacteria. Finally, we summarize implications for ecosystem management. Although we have gained tremendous insights into understanding linkages between ecosystem functions and the various aspects of mycorrhizal diversity, very little is known regarding rhizosphere communities in PHC-contaminated soils. This makes it difficult to translate ecological knowledge into environmental management strategies. Further research is required to determine which fungal symbionts are likely to survive and compete in various ecosystems, whether certain fungal - plant associations gain in ecological importance following contamination events, and how PHC contamination may interfere with processes of nutrient acquisition and exchange and metabolic processes. Research is also needed to assess whether the metabolic capacity for intrinsic decomposition exists in these ecosystems, taking into account ecological variables such as presence of other organisms (and their involvement in syntrophic biodegradation), bioavailability and toxicity of mixtures of PHCs, and physical changes to the soil environment.
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Sleeter, Benjamin M.; Liu, Jinxun; Daniel, Colin; Rayfield, Bronwyn; Sherba, Jason; Hawbaker, Todd J.; Zhu, Zhiliang; Selmants, Paul; Loveland, Thomas R.
2018-01-01
Changes in land use and land cover (LULC) can have profound effects on terrestrial carbon dynamics, yet their effects on the global carbon budget remain uncertain. While land change impacts on ecosystem carbon dynamics have been the focus of numerous studies, few efforts have been based on observational data incorporating multiple ecosystem types spanning large geographic areas over long time horizons. In this study we use a variety of synoptic-scale remote sensing data to estimate the effect of LULC changes associated with urbanization, agricultural expansion and contraction, forest harvest, and wildfire on the carbon balance of terrestrial ecosystems (forest, grasslands, shrublands, and agriculture) in the conterminous United States (i.e. excluding Alaska and Hawaii) between 1973 and 2010. We estimate large net declines in the area of agriculture and forest, along with relatively small increases in grasslands and shrublands. The largest net change in any class was an estimated gain of 114 865 km2 of developed lands, an average rate of 3282 km2 yr−1. On average, US ecosystems sequestered carbon at an annual rate of 254 Tg C yr−1. In forest lands, the net sink declined by 35% over the study period, largely a result of land-use legacy, increasing disturbances, and reductions in forest area due to land use conversion. Uncertainty in LULC change data contributed to a ~16% margin of error in the annual carbon sink estimate prior to 1985 (approximately ±40 Tg C yr−1). Improvements in LULC and disturbance mapping starting in the mid-1980s reduced this uncertainty by ~50% after 1985. We conclude that changes in LULC are a critical component to understanding ecosystem carbon dynamics, and continued improvements in detection, quantification, and attribution of change have the potential to significantly reduce current uncertainties.
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NASA Astrophysics Data System (ADS)
Sleeter, Benjamin M.; Liu, Jinxun; Daniel, Colin; Rayfield, Bronwyn; Sherba, Jason; Hawbaker, Todd J.; Zhu, Zhiliang; Selmants, Paul C.; Loveland, Thomas R.
2018-04-01
Changes in land use and land cover (LULC) can have profound effects on terrestrial carbon dynamics, yet their effects on the global carbon budget remain uncertain. While land change impacts on ecosystem carbon dynamics have been the focus of numerous studies, few efforts have been based on observational data incorporating multiple ecosystem types spanning large geographic areas over long time horizons. In this study we use a variety of synoptic-scale remote sensing data to estimate the effect of LULC changes associated with urbanization, agricultural expansion and contraction, forest harvest, and wildfire on the carbon balance of terrestrial ecosystems (forest, grasslands, shrublands, and agriculture) in the conterminous United States (i.e. excluding Alaska and Hawaii) between 1973 and 2010. We estimate large net declines in the area of agriculture and forest, along with relatively small increases in grasslands and shrublands. The largest net change in any class was an estimated gain of 114 865 km2 of developed lands, an average rate of 3282 km2 yr‑1. On average, US ecosystems sequestered carbon at an annual rate of 254 Tg C yr‑1. In forest lands, the net sink declined by 35% over the study period, largely a result of land-use legacy, increasing disturbances, and reductions in forest area due to land use conversion. Uncertainty in LULC change data contributed to a ~16% margin of error in the annual carbon sink estimate prior to 1985 (approximately ±40 Tg C yr‑1). Improvements in LULC and disturbance mapping starting in the mid-1980s reduced this uncertainty by ~50% after 1985. We conclude that changes in LULC are a critical component to understanding ecosystem carbon dynamics, and continued improvements in detection, quantification, and attribution of change have the potential to significantly reduce current uncertainties.
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Selmants, Paul C; Litton, Creighton M; Giardina, Christian P; Asner, Gregory P
2014-09-01
Theory and experiment agree that climate warming will increase carbon fluxes between terrestrial ecosystems and the atmosphere. The effect of this increased exchange on terrestrial carbon storage is less predictable, with important implications for potential feedbacks to the climate system. We quantified how increased mean annual temperature (MAT) affects ecosystem carbon storage in above- and belowground live biomass and detritus across a well-constrained 5.2 °C MAT gradient in tropical montane wet forests on the Island of Hawaii. This gradient does not systematically vary in biotic or abiotic factors other than MAT (i.e. dominant vegetation, substrate type and age, soil water balance, and disturbance history), allowing us to isolate the impact of MAT on ecosystem carbon storage. Live biomass carbon did not vary predictably as a function of MAT, while detrital carbon declined by ~14 Mg of carbon ha(-1) for each 1 °C rise in temperature - a trend driven entirely by coarse woody debris and litter. The largest detrital pool, soil organic carbon, was the most stable with MAT and averaged 48% of total ecosystem carbon across the MAT gradient. Total ecosystem carbon did not vary significantly with MAT, and the distribution of ecosystem carbon between live biomass and detritus remained relatively constant across the MAT gradient at ~44% and ~56%, respectively. These findings suggest that in the absence of alterations to precipitation or disturbance regimes, the size and distribution of carbon pools in tropical montane wet forests will be less sensitive to rising MAT than predicted by ecosystem models. This article also provides needed detail on how individual carbon pools and ecosystem-level carbon storage will respond to future warming. © 2014 John Wiley & Sons Ltd.
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Joe H. Scott; Donald J. Helmbrecht; Sean A. Parks; Carol Miller
2012-01-01
An important objective for many federal land management agencies is to restore fire to ecosystems that have experienced fire suppression or exclusion over the last century. Managing wildfires for resource objectives (i.e., allowing wildfires to burn in the absence of suppression) is an important tool for restoring such fire-adapted ecosystems. To support management...
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Restoration of the ponderosa pine ecosystem and its understory
Lee E. Hughes
2008-01-01
Restoration of the Mt. Logan ponderosa pine ecosystem has been on-going since 1995. This effort included tree thinning to a density based on what the tree density was in 1870. The desired plant community objectives from the Mt. Trumbull Resource Conservation Area Plan had a forest objective as 50% trees to be in old-growth - i.e., a diameter class of 20-31.9+ inch...
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[Wetlands dominated by palms (Arecaceae), emphasis in those in the New World].
Myers, Ronald L
2013-09-01
It is well known that most forests in humid tropical lowlands are species rich, and the popular view is that most species are represented by only a few individuals. Despite this common understanding of high richness and low species dominance, within humid tropical regions there are extensive forested ecosystems composed by only few species. These nearly monospecific forests usually occupy poorly drained soils and, except for the mangroves, are quite understudied. In this paper, I review the literature and my own field notes on more than three years studying the structure of palm swamps in Caribbean Costa Rica and Florida to describe some of the major vegetation associations in wetlands dominated by palm species in the Neotropical Region, although I also include some information about similar systems in the Old World Tropics. I mention the most abundant species that compose those palm dominated swamps and -whenever possible- describe forest structure, known distribution, and uses.
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Estimation of biogeochemical climate regulation services in Chinese forest ecosystems
NASA Astrophysics Data System (ADS)
Zhang, Y.; Li, S.
2016-12-01
As the global climate is changing, the climate regulation service of terrestrial ecosystem has been widely studied. Forests, as one of the most important terrestrial ecosystem types, is the biggest carbon pool or sink on land and can regulate climate through both biophysical and biogeochemical means. China is a country with vast forested areas and a variety of forest ecosystems types. Although current studies have related the climate regulation service of forest in China with biophysical or biogeochemical mechanism, there is still a lack of quantitative estimation of climate regulation services, especially for the biogeochemical climate regulation service. The GHGV (greenhouse gas value) is an indicator that can quantify the biochemical climate regulation service using ecosystems' stored organic matter, annual greenhouse gas flux, and potential greenhouse gas exchange rates during disturbances over a multiple year time frame. Therefore, we used GHGV to estimate the contribution of China's ten main forest types to biogeochemical climate regulation and generate the pattern of biochemical climate regulation service in Chinese forest ecosystems.
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The Missouri Ozark Forest Ecosystem Project: past, present, and future
Brian L. Brookshire; Randy Jensen; Daniel C. Dey
1997-01-01
In 1989, the Missouri Department of Conservation initiated a research project to examine the impacts of forest management practices on multiple ecosystem components. The Missouri Ozark Forest Ecosystem Project (MOFEP) is a landscape experiment comparing the impacts of even-aged management, uneven-aged management, and no harvesting on a wide array of ecosystem...
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Urban forests and pollution mitigation: analyzing ecosystem services and disservices.
Escobedo, Francisco J; Kroeger, Timm; Wagner, John E
2011-01-01
The purpose of this paper is to integrate the concepts of ecosystem services and disservices when assessing the efficacy of using urban forests for mitigating pollution. A brief review of the literature identifies some pollution mitigation ecosystem services provided by urban forests. Existing ecosystem services definitions and typologies from the economics and ecological literature are adapted and applied to urban forest management and the concepts of ecosystem disservices from natural and semi-natural systems are discussed. Examples of the urban forest ecosystem services of air quality and carbon dioxide sequestration are used to illustrate issues associated with assessing their efficacy in mitigating urban pollution. Development of urban forest management alternatives that mitigate pollution should consider scale, contexts, heterogeneity, management intensities and other social and economic co-benefits, tradeoffs, and costs affecting stakeholders and urban sustainability goals. Copyright © 2011 Elsevier Ltd. All rights reserved.
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Forest ecosystem services: Provisioning of non-timber forest products
James L. Chamberlain; Gregory E. Frey; C. Denise Ingram; Michael G. Jacobson; Cara Meghan Starbuck Downes
2017-01-01
The purpose of this chapter is to describe approaches to calculate a conservative and defensible estimate of the marginal value of forests for non-timber forest products (NTFPs). 'Provisioning" is one of four categories of benefits, or services that ecosystems provide to humans and was described by the Millennium Ecosystem Assessment as 'products...
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Forest-land conversion, ecosystem services, and economic issues for policy: a review
Robert A. Smail; David J. Lewis
2009-01-01
The continued conversion and development of forest land pose a serious threat to the ecosystem services derived from forested landscapes. We argue that developing an understanding of the full range of consequences from forest conversion requires understanding the effects of such conversion on both components of ecosystem services: products and processes....
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Forest Ecosystem Services As Production Inputs
Subhrendu Pattanayak; David T. Butry
2003-01-01
Are we cutting down tropical forests too rapidly and too extensively? If so, why? Answers to both questions are obscured in some ways by insufficient and unreliable data on the economic worth of forest ecosystem services. It is clear, however, that rapid, excessive cutting of forests can irreversibly and substantively impair ecosystem functions, thereby endangering the...
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Forest ecosystem services: Carbon and air quality
David J. Nowak; Neelam C. Poudyal; Steve G. McNulty
2017-01-01
Forests provide various ecosystem services related to air quality that can provide substantial value to society. Through tree growth and alteration of their local environment, trees and forests both directly and indirectly affect air quality. Though forests affect air quality in numerous ways, this chapter will focus on five main ecosystem services or disservices...
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Forest Ecosystem Dynamics Assessment and Predictive Modelling in Eastern Himalaya
NASA Astrophysics Data System (ADS)
Kushwaha, S. P. S.; Nandy, S.; Ahmad, M.; Agarwal, R.
2011-09-01
This study focused on the forest ecosystem dynamics assessment and predictive modelling deforestation and forest cover prediction in a part of north-eastern India i.e. forest areas along West Bengal, Bhutan, Arunachal Pradesh and Assam border in Eastern Himalaya using temporal satellite imagery of 1975, 1990 and 2009 and predicted forest cover for the period 2028 using Cellular Automata Markov Modedel (CAMM). The exercise highlighted large-scale deforestation in the study area during 1975-1990 as well as 1990-2009 forest cover vectors. A net loss of 2,334.28 km2 forest cover was noticed between 1975 and 2009, and with current rate of deforestation, a forest area of 4,563.34 km2 will be lost by 2028. The annual rate of deforestation worked out to be 0.35 and 0.78% during 1975-1990 and 1990-2009 respectively. Bamboo forest increased by 24.98% between 1975 and 2009 due to opening up of the forests. Forests in Kokrajhar, Barpeta, Darrang, Sonitpur, and Dhemaji districts in Assam were noticed to be worst-affected while Lower Subansiri, West and East Siang, Dibang Valley, Lohit and Changlang in Arunachal Pradesh were severely affected. Among different forest types, the maximum loss was seen in case of sal forest (37.97%) between 1975 and 2009 and is expected to deplete further to 60.39% by 2028. The tropical moist deciduous forest was the next category, which decreased from 5,208.11 km2 to 3,447.28 (33.81%) during same period with further chances of depletion to 2,288.81 km2 (56.05%) by 2028. It noted progressive loss of forests in the study area between 1975 and 2009 through 1990 and predicted that, unless checked, the area is in for further depletion of the invaluable climax forests in the region, especially sal and moist deciduous forests. The exercise demonstrated high potential of remote sensing and geographic information system for forest ecosystem dynamics assessment and the efficacy of CAMM to predict the forest cover change.
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Divergence of ecosystem services in U.S. National Forests and Grasslands under a changing climate.
Duan, Kai; Sun, Ge; Sun, Shanlei; Caldwell, Peter V; Cohen, Erika C; McNulty, Steven G; Aldridge, Heather D; Zhang, Yang
2016-04-21
The 170 National Forests and Grasslands (NFs) in the conterminous United States are public lands that provide important ecosystem services such as clean water and timber supply to the American people. This study investigates the potential impacts of climate change on two key ecosystem functions (i.e., water yield and ecosystem productivity) using the most recent climate projections derived from 20 Global Climate Models (GCMs) of the Coupled Model Intercomparison Project phase 5 (CMIP5). We find that future climate change may result in a significant reduction in water yield but an increase in ecosystem productivity in NFs. On average, gross ecosystem productivity is projected to increase by 76 ~ 229 g C m(-2) yr(-1) (8% ~ 24%) while water yield is projected to decrease by 18 ~ 31 mm yr(-1) (4% ~ 7%) by 2100 as a result of the combination of increased air temperature (+1.8 ~ +5.2 °C) and precipitation (+17 ~ +51 mm yr(-1)). The notable divergence in ecosystem services of water supply and carbon sequestration is expected to intensify under higher greenhouse gas emission and associated climate change in the future, posing greater challenges to managing NFs for both ecosystem services.
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NASA Astrophysics Data System (ADS)
Fang, F. J.
2017-12-01
Reconciling observations at fundamentally different scales is central in understanding the global carbon cycle. This study investigates a model-based melding of forest inventory data, remote-sensing data and micrometeorological-station data ("flux towers" estimating forest heat, CO2 and H2O fluxes). The individual tree-based model FORCCHN was used to evaluate the tree DBH increment and forest carbon fluxes. These are the first simultaneous simulations of the forest carbon budgets from flux towers and individual-tree growth estimates of forest carbon budgets using the continuous forest inventory data — under circumstances in which both predictions can be tested. Along with the global implications of such findings, this also improves the capacity for forest sustainable management and the comprehensive understanding of forest ecosystems. In forest ecology, diameter at breast height (DBH) of a tree significantly determines an individual tree's cross-sectional sapwood area, its biomass and carbon storage. Evaluation the annual DBH increment (ΔDBH) of an individual tree is central to understanding tree growth and forest ecology. Ecosystem Carbon flux is a consequence of key ecosystem processes in the forest-ecosystem carbon cycle, Gross and Net Primary Production (GPP and NPP, respectively) and Net Ecosystem Respiration (NEP). All of these closely relate with tree DBH changes and tree death. Despite advances in evaluating forest carbon fluxes with flux towers and forest inventories for individual tree ΔDBH, few current ecological models can simultaneously quantify and predict the tree ΔDBH and forest carbon flux.
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Wolfslehner, Bernhard; Seidl, Rupert
2010-12-01
The decision-making environment in forest management (FM) has changed drastically during the last decades. Forest management planning is facing increasing complexity due to a widening portfolio of forest goods and services, a societal demand for a rational, transparent decision process and rising uncertainties concerning future environmental conditions (e.g., climate change). Methodological responses to these challenges include an intensified use of ecosystem models to provide an enriched, quantitative information base for FM planning. Furthermore, multi-criteria methods are increasingly used to amalgamate information, preferences, expert judgments and value expressions, in support of the participatory and communicative dimensions of modern forestry. Although the potential of combining these two approaches has been demonstrated in a number of studies, methodological aspects in interfacing forest ecosystem models (FEM) and multi-criteria decision analysis (MCDA) are scarcely addressed explicitly. In this contribution we review the state of the art in FEM and MCDA in the context of FM planning and highlight some of the crucial issues when combining ecosystem and preference modeling. We discuss issues and requirements in selecting approaches suitable for supporting FM planning problems from the growing body of FEM and MCDA concepts. We furthermore identify two major challenges in a harmonized application of FEM-MCDA: (i) the design and implementation of an indicator-based analysis framework capturing ecological and social aspects and their interactions relevant for the decision process, and (ii) holistic information management that supports consistent use of different information sources, provides meta-information as well as information on uncertainties throughout the planning process.
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NASA Astrophysics Data System (ADS)
Wolfslehner, Bernhard; Seidl, Rupert
2010-12-01
The decision-making environment in forest management (FM) has changed drastically during the last decades. Forest management planning is facing increasing complexity due to a widening portfolio of forest goods and services, a societal demand for a rational, transparent decision process and rising uncertainties concerning future environmental conditions (e.g., climate change). Methodological responses to these challenges include an intensified use of ecosystem models to provide an enriched, quantitative information base for FM planning. Furthermore, multi-criteria methods are increasingly used to amalgamate information, preferences, expert judgments and value expressions, in support of the participatory and communicative dimensions of modern forestry. Although the potential of combining these two approaches has been demonstrated in a number of studies, methodological aspects in interfacing forest ecosystem models (FEM) and multi-criteria decision analysis (MCDA) are scarcely addressed explicitly. In this contribution we review the state of the art in FEM and MCDA in the context of FM planning and highlight some of the crucial issues when combining ecosystem and preference modeling. We discuss issues and requirements in selecting approaches suitable for supporting FM planning problems from the growing body of FEM and MCDA concepts. We furthermore identify two major challenges in a harmonized application of FEM-MCDA: (i) the design and implementation of an indicator-based analysis framework capturing ecological and social aspects and their interactions relevant for the decision process, and (ii) holistic information management that supports consistent use of different information sources, provides meta-information as well as information on uncertainties throughout the planning process.
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Legacy effects of land-use modulate tree growth responses to climate extremes.
Mausolf, Katharina; Härdtle, Werner; Jansen, Kirstin; Delory, Benjamin M; Hertel, Dietrich; Leuschner, Christoph; Temperton, Vicky M; von Oheimb, Goddert; Fichtner, Andreas
2018-05-10
Climate change can impact forest ecosystem processes via individual tree and community responses. While the importance of land-use legacies in modulating these processes have been increasingly recognised, evidence of former land-use mediated climate-growth relationships remain rare. We analysed how differences in former land-use (i.e. forest continuity) affect the growth response of European beech to climate extremes. Here, using dendrochronological and fine root data, we show that ancient forests (forests with a long forest continuity) and recent forests (forests afforested on former farmland) clearly differ with regard to climate-growth relationships. We found that sensitivity to climatic extremes was lower for trees growing in ancient forests, as reflected by significantly lower growth reductions during adverse climatic conditions. Fine root morphology also differed significantly between the former land-use types: on average, trees with high specific root length (SRL) and specific root area (SRA) and low root tissue density (RTD) were associated with recent forests, whereas the opposite traits were characteristic of ancient forests. Moreover, we found that trees of ancient forests hold a larger fine root system than trees of recent forests. Our results demonstrate that land-use legacy-mediated modifications in the size and morphology of the fine root system act as a mechanism in regulating drought resistance of beech, emphasising the need to consider the 'ecological memory' of forests when assessing or predicting the sensitivity of forest ecosystems to global environmental change.
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A dynamic ecosystem growth model for forests at high complexity structure
NASA Astrophysics Data System (ADS)
Collalti, A.; Perugini, L.; Chiti, T.; Matteucci, G.; Oriani, A.; Santini, M.; Papale, D.; Valentini, R.
2012-04-01
Forests ecosystem play an important role in carbon cycle, biodiversity conservation and for other ecosystem services and changes in their structure and status perturb a delicate equilibrium that involves not only vegetation components but also biogeochemical cycles and global climate. The approaches to determine the magnitude of these effects are nowadays various and one of those include the use of models able to simulate structural changes and the variations in forests yield The present work shows the development of a forest dynamic model, on ecosystem spatial scale using the well known light use efficiency to determine Gross Primary Production. The model is predictive and permits to simulate processes that determine forest growth, its dynamic and the effects of forest management using eco-physiological parameters easy to be assessed and to be measured. The model has been designed to consider a tri-dimensional cell structure composed by different vertical layers depending on the forest type that has to be simulated. These features enable the model to work on multi-layer and multi-species forest types, typical of Mediterranean environment, at the resolution of one hectare and at monthly time-step. The model simulates, for each layer, a value of available Photosynthetic Active Radiation (PAR) through Leaf Area Index, Light Extinction Coefficient and cell coverage, the transpiration rate that is closely linked to the intercepted light and the evaporation from soil. Using this model it is possible to evaluate the possible impacts of climate change on forests that may result in decrease or increase of productivity as well as the feedback of one or more dominated layers in terms of CO2 uptake in a forest stand and the effects of forest management activities during the forest harvesting cycle. The model has been parameterised, validated and applied in a multi-layer, multi-age and multi-species Italian turkey oak forest (Q. cerris L., C. betulus L. and C. avellana L.) where the medium-term (10 years) development of forest parameters were simulated. The results obtained for net primary production and for stem, root and foliage compartments as well as for forest structure i.e. Diameter at Breast Height, height and canopy cover are in good accordance with field data (R2>0.95). These results show how the model is able to predict forest yield as well as forest dynamic with good accuracy and encourage testing the model capability on other sites with a more complex forest structure and for long-time period with an higher spatial resolution.
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Maintaining ecosystem function and services in logged tropical forests.
Edwards, David P; Tobias, Joseph A; Sheil, Douglas; Meijaard, Erik; Laurance, William F
2014-09-01
Vast expanses of tropical forests worldwide are being impacted by selective logging. We evaluate the environmental impacts of such logging and conclude that natural timber-production forests typically retain most of their biodiversity and associated ecosystem functions, as well as their carbon, climatic, and soil-hydrological ecosystem services. Unfortunately, the value of production forests is often overlooked, leaving them vulnerable to further degradation including post-logging clearing, fires, and hunting. Because logged tropical forests are extensive, functionally diverse, and provide many ecosystem services, efforts to expand their role in conservation strategies are urgently needed. Key priorities include improving harvest practices to reduce negative impacts on ecosystem functions and services, and preventing the rapid conversion and loss of logged forests. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Pollination and seed dispersal are the most threatened processes of plant regeneration
NASA Astrophysics Data System (ADS)
Neuschulz, Eike Lena; Mueller, Thomas; Schleuning, Matthias; Böhning-Gaese, Katrin
2016-07-01
Plant regeneration is essential for maintaining forest biodiversity and ecosystem functioning, which are globally threatened by human disturbance. Here we present the first integrative meta-analysis on how forest disturbance affects multiple ecological processes of plant regeneration including pollination, seed dispersal, seed predation, recruitment and herbivory. We analysed 408 pairwise comparisons of these processes between near-natural and disturbed forests. Human impacts overall reduced plant regeneration. Importantly, only processes early in the regeneration cycle that often depend on plant-animal interactions, i.e. pollination and seed dispersal, were negatively affected. Later processes, i.e. seed predation, recruitment and herbivory, showed overall no significant response to human disturbance. Conserving pollination and seed dispersal, including the animals that provide these services to plants, should become a priority in forest conservation efforts globally.
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Effects of repeated fires on ecosystem C and N stocks along a fire induced forest/grassland gradient
NASA Astrophysics Data System (ADS)
Cheng, Chih-Hsin; Chen, Yung-Sheng; Huang, Yu-Hsuan; Chiou, Chyi-Rong; Lin, Chau-Chih; Menyailo, Oleg V.
2013-03-01
Repeated fires might have different effect on ecosystem carbon storage than a single fire event, but information on repeated fires and their effects on forest ecosystems and carbon storage is scarce. However, changes in climate, vegetation composition, and human activities are expected to make forests more susceptible to fires that recur with relatively high frequency. In this study, the effects of repeated fires on ecosystem carbon and nitrogen stocks were examined along a fire-induced forest/grassland gradient wherein the fire events varied from an unburned forest to repeatedly burned grassland. Results from the study show repeated fires drastically decreased ecosystem carbon and nitrogen stocks along the forest/grassland gradient. The reduction began with the disappearance of living tree biomass, and followed by the loss of soil carbon and nitrogen. Within 4 years of the onset of repeated fires on the unburned forest, the original ecosystem carbon and nitrogen stocks were reduced by 42% and 21%, respectively. Subsequent fires caused cumulative reductions in ecosystem carbon and nitrogen stocks by 68% and 44% from the original ecosystem carbon and nitrogen stocks, respectively. The analyses of carbon budgets calculated by vegetation composition and stable isotopic δ13C values indicate that 84% of forest-derived carbon is lost at grassland, whereas the gain of grass-derived carbon only compensates 18% for this loss. Such significant losses in ecosystem carbon and nitrogen stocks suggest that the effects of repeated fires have substantial impacts on ecosystem and soil carbon and nitrogen cycling.
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Paoletti, E; Schaub, M; Matyssek, R; Wieser, G; Augustaitis, A; Bastrup-Birk, A M; Bytnerowicz, A; Günthardt-Goerg, M S; Müller-Starck, G; Serengil, Y
2010-06-01
Over the past 20 years, the focus of forest science on air pollution has moved from forest decline to a holistic framework of forest health, and from the effects on forest production to the ecosystem services provided by forest ecosystems. Hence, future research should focus on the interacting factorial impacts and resulting antagonistic and synergistic responses of forest trees and ecosystems. The synergistic effects of air pollution and climatic changes, in particular elevated ozone, altered nitrogen, carbon and water availability, must be key issues for research. Present evidence suggests air pollution will become increasingly harmful to forests under climate change, which requires integration amongst various stressors (abiotic and biotic factors, including competition, parasites and fire), effects on forest services (production, biodiversity protection, soil protection, sustained water balance, socio-economical relevance) and assessment approaches (research, monitoring, modeling) to be fostered. Copyright 2009 Elsevier Ltd. All rights reserved.
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Dynamics of ecosystem services provided by subtropical ...
The trends in the provision of ecosystem services during restoration and succession of subtropical forests and plantations were quantified, in terms of both receiver and donor values, based on a case study of a 3-step secondary succession series that included a 400-year-old subtropical forest and a 23-year history of growth on 3 subtropical forest plantations in Southeastern China. The ‘People's Republic of China Forestry Standard: Forest Ecosystem Service Valuation Norms’ was revised and applied to quantify the receiver values of ecosystem services, which were then compared with the emergy-based, donor values of the services. The results revealed that the efficiencies of subtropical forests and plantations in providing ecosystem services were 2 orders of magnitude higher than similar services provided by the current China economic system, and these efficiencieskept increasing over the course of succession. As a result, we conclude that afforestation is an efficient way to accelerate both the ability and efficiency of subtropical forests to provide ecosystem services. This paper is significant because it examines the dynamics of the provision of ecosystem services by forests over a succession series that spans 400 years. The paper also examines the rate of increase of services during forest restoration over a period of 23 years. The emergy used in ecosystem services provision is compared to the provision of similar services by economic means in the Chinese e
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The linkages between photosynthesis, productivity, growth and biomass in lowland Amazonian forests.
Malhi, Yadvinder; Doughty, Christopher E; Goldsmith, Gregory R; Metcalfe, Daniel B; Girardin, Cécile A J; Marthews, Toby R; Del Aguila-Pasquel, Jhon; Aragão, Luiz E O C; Araujo-Murakami, Alejandro; Brando, Paulo; da Costa, Antonio C L; Silva-Espejo, Javier E; Farfán Amézquita, Filio; Galbraith, David R; Quesada, Carlos A; Rocha, Wanderley; Salinas-Revilla, Norma; Silvério, Divino; Meir, Patrick; Phillips, Oliver L
2015-06-01
Understanding the relationship between photosynthesis, net primary productivity and growth in forest ecosystems is key to understanding how these ecosystems will respond to global anthropogenic change, yet the linkages among these components are rarely explored in detail. We provide the first comprehensive description of the productivity, respiration and carbon allocation of contrasting lowland Amazonian forests spanning gradients in seasonal water deficit and soil fertility. Using the largest data set assembled to date, ten sites in three countries all studied with a standardized methodology, we find that (i) gross primary productivity (GPP) has a simple relationship with seasonal water deficit, but that (ii) site-to-site variations in GPP have little power in explaining site-to-site spatial variations in net primary productivity (NPP) or growth because of concomitant changes in carbon use efficiency (CUE), and conversely, the woody growth rate of a tropical forest is a very poor proxy for its productivity. Moreover, (iii) spatial patterns of biomass are much more driven by patterns of residence times (i.e. tree mortality rates) than by spatial variation in productivity or tree growth. Current theory and models of tropical forest carbon cycling under projected scenarios of global atmospheric change can benefit from advancing beyond a focus on GPP. By improving our understanding of poorly understood processes such as CUE, NPP allocation and biomass turnover times, we can provide more complete and mechanistic approaches to linking climate and tropical forest carbon cycling. © 2015 John Wiley & Sons Ltd.
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The effect of climate variability on the carbon cycle of a Mediterranean forest
NASA Astrophysics Data System (ADS)
Manca, G.; Tirone, G.; Matteucci, G.; Tonon, G.; Cherubini, P.; Goded Ballarin, I.; Duerr, M.; Matteucci, M.; Seufert, G.
2009-04-01
Measurements of Net Ecosystem Exchange (NEE) of carbon dioxide have operated since 1999 in the Mediterranean forest ecosystem (Pinus pinaster, L.) located in San Rossore (Pisa - Italy). Using night time values of NEE it is possible to estimate the Ecosystem Respiration (Reco) and the Gross Ecosystem Productivity (GEP), i.e. the photosynthetic uptake of CO2 without respiratory losses. The analysis of such fluxes shows that on annual base San Rossore is a CO2 sink. This ecosystem experiences a strong reduction of carbon uptake during summer when the rainfall is low and the air temperature is high. In such condition trees close stomata in order to avoid alteration of the leaf water status. This is the typical behaviour of the drought avoiding species. The reduction of the carbon uptake is due mainly to a reduction of photosynthesis whereas the ecosystem respiration undergoes a lower decrease. The summer 2003 is an extreme example of this pattern. The long time series collected in San Rossore allows to test the reaction of the forest to a wet summer (summer 2002), when the rainfall was 506 mm (300 mm more than the summer average 1999-2007), and the effect of high temperature in winter (January 2007). During summer 2002 both GEP and Reco were higher than the average but the GEP experienced the higher increase. The high temperature in January 2007 (3 °C higher than the average 1999-2007), was responsible for the huge increase of the ecosystem respiration not balanced by the little increase of GEP.
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NASA Astrophysics Data System (ADS)
Fu, W. J.; Jiang, P. K.; Zhou, G. M.; Zhao, K. L.
2013-12-01
The spatial variation of forest litter carbon (FLC) density in the typical subtropical forests in southeast China was investigated using Moran's I, geostatistics and a geographical information system (GIS). A total of 839 forest litter samples were collected based on a 12 km (South-North) × 6 km (East-West) grid system in Zhejiang Province. Forest litter carbon density values were very variable, ranging from 10.2 kg ha-1 to 8841.3 kg ha-1, with an average of 1786.7 kg ha-1. The aboveground biomass had the strongest positive correlation with FLC density, followed by forest age and elevation. Global Moran's I revealed that FLC density had significant positive spatial autocorrelation. Clear spatial patterns were observed using Local Moran's I. A spherical model was chosen to fit the experimental semivariogram. The moderate "nugget-to-sill" (0.536) value revealed that both natural and anthropogenic factors played a key role in spatial heterogeneity of FLC density. High FLC density values were mainly distributed in northwestern and western part of Zhejiang province, which were related to adopting long-term policy of forest conservation in these areas. While Hang-Jia-Hu (HJH) Plain, Jin-Qu (JQ) basin and coastal areas had low FLC density due to low forest coverage and intensive management of economic forests. These spatial patterns in distribution map were in line with the spatial-cluster map described by local Moran's I. Therefore, Moran's I, combined with geostatistics and GIS could be used to study spatial patterns of environmental variables related to forest ecosystem.
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Robert L. Deal; Nikola Smith; Joe Gates
2017-01-01
Ecosystem services are increasingly recognized as a way of framing and describing the broad suite of benefits that people receive from forests. The USDA Forest Service has been exploring use of an ecosystem services framework to describe forest values provided by federal lands and to attract and build partnerships with stakeholders to implement projects. Recently, the...
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Maria K. Janowiak; Louis R. Iverson; David J. Mladenoff; Emily Peters; Kirk R. Wythers; Weimin Xi; Leslie A. Brandt; Patricia R. Butler; Stephen D. Handler; P. Danielle Shannon; Chris Swanston; Linda R. Parker; Amy J. Amman; Brian Bogaczyk; Christine Handler; Ellen Lesch; Peter B. Reich; Stephen Matthews; Matthew Peters; Anantha Prasad; Sami Khanal; Feng Liu; Tara Bal; Dustin Bronson; Andrew Burton; Jim Ferris; Jon Fosgitt; Shawn Hagan; Erin Johnston; Evan Kane; Colleen Matula; Ryan O' Connor; Dale Higgins; Matt St. Pierre; Jad Daley; Mae Davenport; Marla R. Emery; David Fehringer; Christopher L. Hoving; Gary Johnson; David Neitzel; Michael Notaro; Adena Rissman; Chadwick Rittenhouse; Robert Ziel
2014-01-01
Forest ecosystems across the Northwoods will face direct and indirect impacts from a changing climate over the 21st century. This assessment evaluates the vulnerability of forest ecosystems in the Laurentian Mixed Forest Province of northern Wisconsin and western Upper Michigan under a range of future climates. Information on current forest conditions, observed climate...
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Tree diversity does not always improve resistance of forest ecosystems to drought.
Grossiord, Charlotte; Granier, André; Ratcliffe, Sophia; Bouriaud, Olivier; Bruelheide, Helge; Chećko, Ewa; Forrester, David Ian; Dawud, Seid Muhie; Finér, Leena; Pollastrini, Martina; Scherer-Lorenzen, Michael; Valladares, Fernando; Bonal, Damien; Gessler, Arthur
2014-10-14
Climate models predict an increase in the intensity and frequency of drought episodes in the Northern Hemisphere. Among terrestrial ecosystems, forests will be profoundly impacted by drier climatic conditions, with drastic consequences for the functions and services they supply. Simultaneously, biodiversity is known to support a wide range of forest ecosystem functions and services. However, whether biodiversity also improves the resistance of these ecosystems to drought remains unclear. We compared soil drought exposure levels in a total of 160 forest stands within five major forest types across Europe along a gradient of tree species diversity. We assessed soil drought exposure in each forest stand by calculating the stand-level increase in carbon isotope composition of late wood from a wet to a dry year (Δδ(13)CS). Δδ(13)CS exhibited a negative linear relationship with tree species diversity in two forest types, suggesting that species interactions in these forests diminished the drought exposure of the ecosystem. However, the other three forest types were unaffected by tree species diversity. We conclude that higher diversity enhances resistance to drought events only in drought-prone environments. Managing forest ecosystems for high tree species diversity does not necessarily assure improved adaptability to the more severe and frequent drought events predicted for the future.
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A framework for developing urban forest ecosystem services and goods indicators
Cynnamon Dobbs; Francisco J. Escobedo; Wayne C. Zipperer
2011-01-01
The social and ecological processes impacting on urban forests have been studied at multiple temporal and spatial scales in order to help us quantify, monitor, and value the ecosystem services that benefit people. Few studies have comprehensively analyzed the full suite of ecosystem services, goods (ESG), and ecosystem disservices provided by an urban forest....
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Constance I. Millar
1996-01-01
To assess the various ways organizations and people come together to manage Sierran ecosystems, SNEP conducted four case studies to examine the efficacy of different institutional arrangements:The Mammoth-June case study examines how a single national forest is attempting to implement the new Forest Service policy for ecosystem analysis...
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Vegetation and environmental features of forest and range ecosystems
George A. Garrison; Ardell J. Bjugstad; Don A. Duncan; Mont E. Lewis; Dixie R. Smith
1977-01-01
This publication describes the 34 ecosystems into which all the land of the 48 contiguous states has been classified in the Forest-Range Environmental Study (FRES) of the Forest Service, U.S. Department of Agriculture. The description of each ecosystem discusses physiography, climate, vegetation, fauna, soils, and land use. For a number of the ecosystems, the...
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This EnviroAtlas dataset contains polygons depicting the number of watershed-level market-based programs, referred to herein as markets, in operation per 8-digit HUC watershed throughout the United States. The data were collected via surveys and desk research conducted by Forest Trends' Ecosystem Marketplace during 2014 regarding markets operating to protect watershed ecosystem services. Utilizing these data, the number of water market coverage areas overlaying each HUC8 watershed were calculated to produce this dataset. Only water markets identified as operating at the watershed level (i.e., single or multiple watersheds define the market boundaries) were included in the count of water markets per HUC8 watershed. Excluded were water markets operating at the national, state, county, or federal lands level and all water projects. Attribute data include the watershed's 8-digit hydrologic unit code and name, in addition to the watershed-level water market count associated with the watershed. This dataset was produced by Forest Trends' Ecosystem Marketplace to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Addi
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An Integrated Approach to Forest Ecosystem Services
José Joaquin Campos; Francisco Alpizar; Bastiaan Louman; John A. Parrotta
2005-01-01
Forest ecosystem services (FES) are fundamental for the Earthâs life support systems. This chapter discusses the different services provided by forest ecosystems and the effects that land use and forest management practices have on their provision. It also discusses the role of markets in providing an enabling environment for a sustainable and equitable provision of...
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The Kings River Sustainable Forest Ecosystems Project: inception, objectives, and progress
Jared Verner; Mark T. Smith
2002-01-01
The Kings River Sustainable Forest Ecosystems Project, a formal administrative study involving extensive and intensive collaboration between Forest Service managers and researchers, is a response to changes in the agencyâs orientation in favor of ecosystem approaches and to recent concern over issues associated with maintenance of late successional forest attributes...
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Historical open forest ecosystems in the Missouri Ozarks: reconstruction and restoration targets
Brice B. Hanberry; D. Todd Jones-Farrand; John M. Kabrick
2014-01-01
Current forests no longer resemble historical open forest ecosystems in the eastern United States. In the absence of representative forest ecosystems under a continuous surface fire regime at a large scale, reconstruction of historical landscapes can provide a reference for restoration efforts. For initial expert-assigned vegetation phases ranging from prairie to...
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Brian L. Brookshire; Daniel C. Dey
2000-01-01
The Missouri Ozark Forest Ecosystem Project (MOFEP) is an experiment designed to determine the effects of forest management practices on important ecosystem attributes. MOFEP treatments evaluated include even-aged, uneven-aged, and no management treatments. Forest vegetation provides a common ecological link among many organisms and ecological processes, and therefore...
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Ianni, Elena; Geneletti, Davide
2010-11-01
This paper proposes a method to select forest restoration priority areas consistently with the key principles of the Ecosystem Approach (EA) and the Forest Landscape Restoration (FLR) framework. The methodology is based on the principles shared by the two approaches: acting at ecosystem scale, involving stakeholders, and evaluating alternatives. It proposes the involvement of social actors which have a stake in forest management through multicriteria analysis sessions aimed at identifying the most suitable forest restoration intervention. The method was applied to a study area in the native forests of Northern Argentina (the Yungas). Stakeholders were asked to identify alternative restoration actions, i.e. potential areas implementing FLR. Ten alternative fincas-estates derived from the Spanish land tenure system-differing in relation to ownership, management, land use, land tenure, and size were evaluated. Twenty criteria were selected and classified into four groups: biophysical, social, economic and political. Finca Ledesma was the closest to the economic, social, environmental and political goals, according to the values and views of the actors involved in the decision. This study represented the first attempt to apply EA principles to forest restoration at landscape scale in the Yungas region. The benefits obtained by the application of the method were twofold: on one hand, researchers and local actors were forced to conceive the Yungas as a complex net of rights rather than as a sum of personal interests. On the other hand, the participatory multicriteria approach provided a structured process for collective decision-making in an area where it has never been implemented.
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Klein, Alexandra-Maria; Steffan-Dewenter, Ingolf; Tscharntke, Teja
2006-03-01
1. Human alteration of natural ecosystems to agroecosystems continues to accelerate in tropical countries. The resulting world-wide decline of rain forest causes a mosaic landscape, comprising simple and complex agroecosystems and patchily distributed rain forest fragments of different quality. Landscape context and agricultural management can be expected to affect both species diversity and ecosystem services by trophic interactions. 2. In Central Sulawesi, Indonesia, 24 agroforestry systems, differing in the distance to the nearest natural forest (0-1415 m), light intensity (37.5-899.6 W/m(-2)) and number of vascular plant species (7-40 species) were studied. Ten standardized trap nests for bees and wasps, made from reed and knotweed internodes, were exposed in each study site. Occupied nests were collected every month, over a period totalling 15 months. 3. A total of 13,617 brood cells were reared to produce adults of 14 trap-nesting species and 25 natural enemy species, which were mostly parasitoids. The total number of species was affected negatively by increasing distance from forest and increased with light intensity of agroforestry systems. The parasitoids in particular appeared to benefit from nearby forests. Over a 500-m distance, the number of parasitoid species decreased from eight to five, and parasitism rates from 12% to 4%. 4. The results show that diversity and parasitism, as a higher trophic interaction and ecosystem service, are enhanced by (i) improved connectivity of agroecosystems with natural habitats such as agroforestry adjacent to rain forest and (ii) management practices to increase light availability in agroforestry, which also enhances richness of flowering plants in the understorey.
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NASA Astrophysics Data System (ADS)
Ianni, Elena; Geneletti, Davide
2010-11-01
This paper proposes a method to select forest restoration priority areas consistently with the key principles of the Ecosystem Approach (EA) and the Forest Landscape Restoration (FLR) framework. The methodology is based on the principles shared by the two approaches: acting at ecosystem scale, involving stakeholders, and evaluating alternatives. It proposes the involvement of social actors which have a stake in forest management through multicriteria analysis sessions aimed at identifying the most suitable forest restoration intervention. The method was applied to a study area in the native forests of Northern Argentina (the Yungas). Stakeholders were asked to identify alternative restoration actions, i.e. potential areas implementing FLR. Ten alternative fincas—estates derived from the Spanish land tenure system—differing in relation to ownership, management, land use, land tenure, and size were evaluated. Twenty criteria were selected and classified into four groups: biophysical, social, economic and political. Finca Ledesma was the closest to the economic, social, environmental and political goals, according to the values and views of the actors involved in the decision. This study represented the first attempt to apply EA principles to forest restoration at landscape scale in the Yungas region. The benefits obtained by the application of the method were twofold: on one hand, researchers and local actors were forced to conceive the Yungas as a complex net of rights rather than as a sum of personal interests. On the other hand, the participatory multicriteria approach provided a structured process for collective decision-making in an area where it has never been implemented.
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Estimating daily forest carbon fluxes using a combination of ground and remotely sensed data
NASA Astrophysics Data System (ADS)
Chirici, Gherardo; Chiesi, Marta; Corona, Piermaria; Salvati, Riccardo; Papale, Dario; Fibbi, Luca; Sirca, Costantino; Spano, Donatella; Duce, Pierpaolo; Marras, Serena; Matteucci, Giorgio; Cescatti, Alessandro; Maselli, Fabio
2016-02-01
Several studies have demonstrated that Monteith's approach can efficiently predict forest gross primary production (GPP), while the modeling of net ecosystem production (NEP) is more critical, requiring the additional simulation of forest respirations. The NEP of different forest ecosystems in Italy was currently simulated by the use of a remote sensing driven parametric model (modified C-Fix) and a biogeochemical model (BIOME-BGC). The outputs of the two models, which simulate forests in quasi-equilibrium conditions, are combined to estimate the carbon fluxes of actual conditions using information regarding the existing woody biomass. The estimates derived from the methodology have been tested against daily reference GPP and NEP data collected through the eddy correlation technique at five study sites in Italy. The first test concerned the theoretical validity of the simulation approach at both annual and daily time scales and was performed using optimal model drivers (i.e., collected or calibrated over the site measurements). Next, the test was repeated to assess the operational applicability of the methodology, which was driven by spatially extended data sets (i.e., data derived from existing wall-to-wall digital maps). A good estimation accuracy was generally obtained for GPP and NEP when using optimal model drivers. The use of spatially extended data sets worsens the accuracy to a varying degree, which is properly characterized. The model drivers with the most influence on the flux modeling strategy are, in increasing order of importance, forest type, soil features, meteorology, and forest woody biomass (growing stock volume).
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Origin of the Hawaiian rainforest ecosystem and its evolution in long-term primary succession
NASA Astrophysics Data System (ADS)
Mueller-Dombois, D.; Boehmer, H. J.
2013-02-01
Born among volcanoes in the north central Pacific about 4 million years ago, the Hawaiian rainforest became assembled from spores of algae, fungi, lichens, bryophytes, ferns and from seeds of about 275 flowering plants that over the millenia evolved into ca. 1000 endemic species. Outstanding among the forest builders were the tree ferns (Cibotium spp.) and the 'Ōhi'a lehua trees (Metrosideros spp.), which still dominate the Hawaiian rainforest ecosystem today. The structure of this forest is simple. The canopy in closed mature rainforests is dominated by cohorts of Metrosideros polymorpha and the undergrowth by tree fern species of Cibotium. When a new lava flow cuts through this forest, kipuka are formed, i.e. islands of remnant vegetation. On the new volcanic substrate, the assemblage of plant life-forms is similar as during the evolution of this system. In open juvenile forests, a mat-forming fern, the uluhe fern (Dicranopteris lineraris) becomes established. It inhibits further regeneration of the dominant 'Ōhi'a tree, thereby reinforcing the cohort structure of the canopy guild. In the later part of its life cycle, the canopy guild breaks down often in synchrony. The trigger is hypothesized to be a climatic perturbation. After that disturbance the forest becomes reestablished in about 30-40 yr. As the volcanic surfaces age, they go from a mesotrophic to a eutrophic phase, reaching a biophilic nutrient climax by about 1-25 K yr. Thereafter, a regressive oligotrophic phase follows; the soils become exhausted of nutrients. The shield volcanoes break down. Marginally, forest habitats change into bogs and stream ecosystems. The broader 'Ōhi'a rainforest redeveloping in the more dissected landscapes of the older islands looses stature, often forming large gaps that are invaded by the aluminum tolerant uluhe fern. The 'Ōhi'a trees still thrive on soils rejuvenated from landslides and from Asian dust on the oldest (5 million year old) island Kaua'i but their stature and living biomass is greatly diminished.
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Smith, W Brad; Cuenca Lara, Rubí Angélica; Delgado Caballero, Carina Edith; Godínez Valdivia, Carlos Isaías; Kapron, Joseph S; Leyva Reyes, Juan Carlos; Meneses Tovar, Carmen Lourdes; Miles, Patrick D; Oswalt, Sonja N; Ramírez Salgado, Mayra; Song, Xilong Alex; Stinson, Graham; Villela Gaytán, Sergio Armando
2018-05-21
Forests cannot be managed sustainably without reliable data to inform decisions. National Forest Inventories (NFI) tend to report national statistics, with sub-national stratification based on domestic ecological classification systems. It is becoming increasingly important to be able to report statistics on ecosystems that span international borders, as global change and globalization expand stakeholders' spheres of concern. The state of a transnational ecosystem can only be properly assessed by examining the entire ecosystem. In global forest resource assessments, it may be useful to break national statistics down by ecosystem, especially for large countries. The Inventory and Monitoring Working Group (IMWG) of the North American Forest Commission (NAFC) has begun developing a harmonized North American Forest Database (NAFD) for managing forest inventory data, enabling consistent, continental-scale forest assessment supporting ecosystem-level reporting and relational queries. The first iteration of the database contains data describing 1.9 billion ha, including 677.5 million ha of forest. Data harmonization is made challenging by the existence of definitions and methodologies tailored to suit national circumstances, emerging from each country's professional forestry development. This paper reports the methods used to synchronize three national forest inventories, starting with a small suite of variables and attributes.
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Davies, Helen J; Doick, Kieron J; Hudson, Malcolm D; Schreckenberg, Kate
2017-07-01
Urbanisation and a changing climate are leading to more frequent and severe flood, heat and air pollution episodes in Britain's cities. Interest in nature-based solutions to these urban problems is growing, with urban forests potentially able to provide a range of regulating ecosystem services such as stormwater attenuation, heat amelioration and air purification. The extent to which these benefits are realized is largely dependent on urban forest management objectives, the availability of funding, and the understanding of ecosystem service concepts within local governments, the primary delivery agents of urban forests. This study aims to establish the extent to which British local authorities actively manage their urban forests for regulating ecosystem services, and identify which resources local authorities most need in order to enhance provision of ecosystem services by Britain's urban forests. Interviews were carried out with staff responsible for tree management decisions in fifteen major local authorities from across Britain, selected on the basis of their urban nature and high population density. Local authorities have a reactive approach to urban forest management, driven by human health and safety concerns and complaints about tree disservices. There is relatively little focus on ensuring provision of regulating ecosystem services, despite awareness by tree officers of the key role that urban forests can play in alleviating chronic air pollution, flood risk and urban heat anomalies. However, this is expected to become a greater focus in future provided that existing constraints - lack of understanding of ecosystem services amongst key stakeholders, limited political support, funding constraints - can be overcome. Our findings suggest that the adoption of a proactive urban forest strategy, underpinned by quantified and valued urban forest-based ecosystem services provision data, and innovative private sector funding mechanisms, can facilitate a change to a proactive, ecosystem services approach to urban forest management. Copyright © 2017. Published by Elsevier Inc.
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Water and the Ecosystems of the Luquillo Experimental Forest
Ariel E. Lugo
1986-01-01
Water dynamics, water balance, and water requirements of the ecosystems and aquatic organisms of the Luquillo Experimental Forest (aka Caribbean National Forest) are reviewed. Objective is to draw attention to research needs and to highlight importance of freshwater allocations to natural ecosystems.
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Modeling carbon and nitrogen biogeochemistry in forest ecosystems
Changsheng Li; Carl Trettin; Ge Sun; Steve McNulty; Klaus Butterbach-Bahl
2005-01-01
A forest biogeochemical model, Forest-DNDC, was developed to quantify carbon sequestration in and trace gas emissions from forest ecosystems. Forest-DNDC was constructed by integrating two existing moels, PnET and DNDC, with several new features including nitrification, forest litter layer, soil freezing and thawing etc, PnET is a forest physiological model predicting...
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Hemiboreal forest: natural disturbances and the importance of ecosystem legacies to management
Kalev Jogiste; Henn Korjus; John Stanturf; Lee E. Frelich; Endijs Baders; Janis Donis; Aris Jansons; Ahto Kangur; Kajar Koster; Diana Laarmann; Tiit Maaten; Vitas Marozas; Marek Metslaid; Kristi Nigul; Olga Polyachenko; Tiit Randveer; Floortje Vodde
2017-01-01
The condition of forest ecosystems depends on the temporal and spatial pattern of management interventions and natural disturbances. Remnants of previous conditions persisting after disturbances, or ecosystem legacies, collectively comprise ecosystem memory. Ecosystem memory in turn contributes to resilience and possibilities of ecosystem reorganization...
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Ganzlin, Peter W; Gundale, Michael J; Becknell, Rachel E; Cleveland, Cory C
2016-07-01
Decades of fire suppression following extensive timber harvesting have left much of the forest in the intermountain western United States exceedingly dense, and forest restoration techniques (i.e., thinning and prescribed fire) are increasingly being used in an attempt to mitigate the effects of severe wildfire, to enhance tree growth and regeneration, and to stimulate soil nutrient cycling. While many of the short-term effects of forest restoration have been established, the long-term effects on soil biogeochemical and ecosystem processes are largely unknown. We assessed the effects of commonly used forest restoration treatments (thinning, burning, and thinning + burning) on nutrient cycling and other ecosystem processes 11 yr after restoration treatments were implemented in a ponderosa pine (Pinus ponderosa var. scopulorum)/Douglas fir (Pseudotsuga menziesii var. glauca) forest at the Lubrecht Fire and Fire Surrogates Study (FFS) site in western Montana, USA. Despite short-term (<3 yr) increases in soil inorganic nitrogen (N) pools and N cycling rates following prescribed fire, long-term soil N pools and N mineralization rates showed only subtle differences from untreated control plots. Similarly, despite a persistent positive correlation between fuels consumed in prescribed burns and several metrics of N cycling, variability in inorganic N pools decreased significantly since treatments were implemented, indicating a decline in N spatial heterogeneity through time. However, rates of net nitrification remain significantly higher in a thin + burn treatment relative to other treatments. Short-term declines in forest floor carbon (C) pools have persisted in the thin + burn treatment, but there were no significant long-term differences among treatments in extractable soil phosphorus (P). Finally, despite some short-term differences, long-term foliar nutrient concentrations, litter decomposition rates, and rates of free-living N fixation in the experimental plots were not different from control plots, suggesting nutrient cycles and ecosystem processes in temperate coniferous forests are resilient to disturbance following long periods of fire suppression. Overall, this study provides forest managers and policymakers valuable information showing that the effects of these commonly used restoration prescriptions on soil nutrient cycling are ephemeral and that use of repeated treatments (i.e., frequent fire) will be necessary to ensure continued restoration success. © 2016 by the Ecological Society of America.
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CO2 flux studies of different hemiboreal forest ecosystems
NASA Astrophysics Data System (ADS)
Krasnova, Alisa; Krasnov, Dmitrii; Noe, Steffen M.; Uri, Veiko; Mander, Ülo; Niinemets, Ülo; Soosaar, Kaido
2017-04-01
Hemiboreal zone is a transition between boreal and temperate zones characterized by the combination of climatic and edaphic conditions inherent in both zones. Hemiboreal forests are typically presented by mixed forests types with different ratios of deciduous and conifer tree species. Dominating tree species composition affects the functioning of forest ecosystem and its influence on biogeochemical cycles. We present the result of ecosystem scale CO2 eddy-covariance fluxes research conducted in 4 ecosystems (3 forests sites and 1 clear-cut area) of hemiboreal zone in Estonia. All 4 sites were developing under similar climatic conditions, but different forest management practices resulted in different composition of dominating tree species: pine forest with spruce trees as a second layer (Soontaga site); spruce/birch forest with single alder trees (Liispõllu site); forest presented by sectors of pine, spruce, birch and clearcut areas (SMEAR Estonia site); 5-years old clearcut area (Kõnnu site).
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Forest Ecosystem Services and Eco-Compensation Mechanisms in China
NASA Astrophysics Data System (ADS)
Deng, Hongbing; Zheng, Peng; Liu, Tianxing; Liu, Xin
2011-12-01
Forests are a major terrestrial ecosystem providing multiple ecosystem services. However, the importance of forests is frequently underestimated from an economic perspective because of the externalities and public good properties of these services. Forest eco-compensation is a transfer mechanism that serves to internalize the externalities of forest ecosystem services by compensating individuals or companies for the losses or costs resulting from the provision of these services. China's current forest eco-compensation system is centered mainly on noncommercial forest. The primary measures associated with ecosystem services are (1) a charge on destructive activities, such as indiscriminate logging, and (2) compensation for individual or local activities and investments in forest conservation. The Compensation Fund System for Forest Ecological Benefits was first listed in the Forest Law of the People's Republic of China in 1998. In 2004, the Central Government Financial Compensation Fund, an important source for the Compensation Fund for Forest Ecological Benefits, was formally established. To improve the forest eco-compensation system, it is crucial to design and establish compensation criteria for noncommercial forests. These criteria should take both theoretical and practical concerns into account, and they should be based on the quantitative valuation of ecosystem services. Although some initial headway has been made on this task, the implementation of an effective forest eco-compensation system in China still has deficiencies and still faces problems. Implementing classification-based and dynamic management for key noncommercial forests and establishing an eco-compensation mechanism with multiple funding sources in the market economy are the key measures needed to conquer these problems and improve the forest eco-compensation system and China's forestry development in sequence.
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Indicator 1.04: Number of native forest-associated species
C. H. Flather; M. S Knowles; C. H. Sieg
2011-01-01
This indicator provides information on the health of forest ecosystems through the number of native forest-associated species. Because one of the more general signs of ecosystem stress is a reduction in the variety of organisms inhabiting a given locale, species counts are often used in assessing ecosystem well-being. The count of forest-associated species in a region...
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Michael P. Amaranthus
1998-01-01
Ectomycorrhizal fungi (EMF) consist of about 5,000 species and profoundly affect forest ecosystems by mediating nutrient and water uptake, protecting roots from pathogens and environmental extremes, and maintaining soil structure and forest food webs. Diversity of EMF likely aids forest ecosystem resilience in the face of changing environmental factors such as...
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Forest Management Devolution: Gap Between Technicians' Design and Villagers' Practices in Madagascar
NASA Astrophysics Data System (ADS)
Rives, Fanny; Carrière, Stéphanie M.; Montagne, Pierre; Aubert, Sigrid; Sibelet, Nicole
2013-10-01
In the 1980s, tropical forest-management principles underwent a shift toward approaches giving greater responsibilities to rural people. One argument for such a shift were the long-term relations established between rural people and their natural resources. In Madagascar, a new law was drawn up in 1996 (Gelose law), which sought to integrate rural people into forest management. A gap was observed between the changes foreseen by the projects implementing the Gelose law and the actual changes. In this article, we use the concept of the social-ecological system (SES) to analyze that gap. The differences existing between the planned changes set by the Gelose contract in the village of Ambatoloaka (northwest of Madagascar) and the practices observed in 2010 were conceptualized as a gap between two SESs. The first SES is the targeted one (i.e., a virtual one); it corresponds to the designed Gelose contract. The second SES is the observed one. It is characterized by the heterogeneity of forest users and uses, which have several impacts on forest management, and by very dynamic social and ecological systems. The observed SES has been reshaped contingent on the constraints and opportunities offered by the Gelose contract as well as on other ecological and social components. The consequences and opportunities that such an SES reshaping would offer to improve the implementation of the Gelose law are discussed. The main reasons explaining the gap between the two SESs are as follows: (1) the clash between static and homogeneous perceptions in the targeted SES and the dynamics and heterogeneity that characterize the observed SES; and (2) the focus on one specific use of forest ecosystems (i.e., charcoal-making) in the targeted SES. Forest management in the observed SES depends on several uses of forest ecosystems.
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Direct quantification of long-term rock nitrogen inputs to temperate forest ecosystems.
Morford, Scott L; Houlton, Benjamin Z; Dahlgren, Randy A
2016-01-01
Sedimentary and metasedimentary rocks contain large reservoirs of fixed nitrogen (N), but questions remain over the importance of rock N weathering inputs in terrestrial ecosystems. Here we provide direct evidence for rock N weathering (i.e., loss of N from rock) in three temperate forest sites residing on a N-rich parent material (820-1050 mg N kg(-1); mica schist) in the Klamath Mountains (northern California and southern Oregon), USA. Our method combines a mass balance model of element addition/ depletion with a procedure for quantifying fixed N in rock minerals, enabling quantification of rock N inputs to bioavailable reservoirs in soil and regolith. Across all sites, -37% to 48% of the initial bedrock N content has undergone long-term weathering in the soil. Combined with regional denudation estimates (sum of physical + chemical erosion), these weathering fractions translate to 1.6-10.7 kg x ha(-1) x yr(-1) of rock N input to these forest ecosystems. These N input fluxes are substantial in light of estimates for atmospheric sources in these sites (4.5-7.0 kg x ha(-1) x yr(-1)). In addition, N depletion from rock minerals was greater than sodium, suggesting active biologically mediated weathering of growth-limiting nutrients compared to nonessential elements. These results point to regional tectonics, biologically mediated weathering effects, and rock N chemistry in shaping the magnitude of rock N inputs to the forest ecosystems examined.
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First evidence of agro-pastoral farming and anthropogenic impact in the Taman Peninsula, Russia
NASA Astrophysics Data System (ADS)
Kaniewski, David; Giaime, Matthieu; Marriner, Nick; Morhange, Christophe; Otto, Thierry; Porotov, Alexey V.; Van Campo, Elise
2015-04-01
Debate on the complex coevolution that has shaped interactions between forested ecosystems and humans through constantly evolving land-use practices over the past millennia has long been centered on the Mediterranean because this area is seen as the cradle for the birth and growth of agricultural activities. Here, we argue that the transition from hunting-gathering by Mesolithic foragers to the food-producing economy of Neolithic farmers was a main trigger of biological changes not only in the Mediterranean but also in the Black Sea and Azov Sea coasts through woodcutting, herding, fire and agriculture. Although the ecological erosion was clearly focused on forested ecosystems, this process seems to have fostered an increased biodiversity. We show, by focusing on the fertile coast of the Azov Sea, that (i) the first evidence of cereal cultivation and human-induced fire occurred in southern Russia 7000 years ago; (ii) the early development of agriculture was a major but discontinuous process; (iii) the coastal ecosystems were rapidly disturbed by anthropogenic activities; and (iv) the Neolithic was a critical threshold for the forested ecosystems of the coastal area. The impact of early anthropogenic pressures seems to have been largely neglected or underestimated for the period encompassing the Neolithic cultural phase.
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Snyder, C.D.; Young, J.A.; Lemarie, D.P.; Smith, D.R.
2002-01-01
We conducted a comparative study in the Delaware Water Gap National Recreation Area to determine the potential long-term impacts of hemlock forest decline on stream benthic macroinvertebrate assemblages. Hemlock forests throughout eastern North America have been declining because of the hemlock woolly adelgid, an exotic insect pest. We found aquatic invertebrate community structure to be strongly correlated with forest composition. Streams draining hemlock forests supported significantly more total taxa than streams draining mixed hardwood forests, and over 8% of the taxa were strongly associated with hemlock. In addition, invertebrate taxa were more evenly distributed (i.e., higher Simpson's evenness values) in hemlock-drained streams. In contrast, the number of rare species and total densities were significantly lower in streams draining hemlock, suggesting that diversity differences observed between forest types were not related to stochastic factors associated with sampling and that streams draining mixed hardwood forests may be more productive. Analysis of stream habitat data indicated that streams draining hemlock forests had more stable thermal and hydrologic regimes. Our findings suggest that hemlock decline may result in long-term changes in headwater ecosystems leading to reductions in both within-stream (i.e., alpha) and park-wide (i.e., gamma) benthic community diversity.
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The role of the atmosphere in the provision of ecosystem services.
Cooter, Ellen J; Rea, Anne; Bruins, Randy; Schwede, Donna; Dennis, Robin
2013-03-15
Solving the environmental problems that we are facing today requires holistic approaches to analysis and decision making that include social and economic aspects. The concept of ecosystem services, defined as the benefits people obtain from ecosystems, is one potential tool to perform such assessments. The objective of this paper is to demonstrate the need for an integrated approach that explicitly includes the contribution of atmospheric processes and functions to the quantification of air-ecosystem services. First, final and intermediate air-ecosystem services are defined. Next, an ecological production function for clean and clear air is described, and its numerical counterpart (the Community Multiscale Air Quality model) is introduced. An illustrative numerical example is developed that simulates potential changes in air-ecosystem services associated with the conversion of evergreen forest land in Mississippi, Alabama and Georgia to commercial crop land. This one-atmosphere approach captures a broad range of service increases and decreases. Results for the forest to cropland conversion scenario suggest that although such change could lead to increased biomass (food) production services, there could also be coincident, seasonally variable decreases in clean and clear air-ecosystem services (i.e., increased levels of ozone and particulate matter) associated with increased fertilizer application. Metrics that support the quantification of these regional air-ecosystem changes require regional ecosystem production functions that fully integrate biotic as well as abiotic components of terrestrial ecosystems, and do so on finer temporal scales than are used for the assessment of most ecosystem services. Published by Elsevier B.V.
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Hess, Steve
2016-01-01
Invasive mammals have irreversibly altered ecosystems of Hawai‘i and other tropical Pacific islands in numerous cases through novel herbivory, predation, and diseases, thereby causing the disproportionate extinction of flora and fauna that occur nowhere else on Earth. The control and eradication of invasive mammals is the single most expensive management activity necessary for restoring ecological integrity to many natural areas of Hawai‘i and other Pacific Islands, and have already advanced the restoration of native biota by removing herbivorous ungulates from >750 km2. Rodenticides which have been tested and registered for hand and aerial broadcast in Hawai‘i have been used to eradicate rats from remote islands to protect nesting seabirds and are now being applied to larger islands to protect forest birds. The exclusion of other invasive mammals is now being undertaken with more sophisticated control techniques and fences. New fence designs are capable of excluding all mammals from areas to protect endangered native birds. Although the eradication of mammals from large areas has resulted in the restoration of some ecosystem processes such as natural forest regeneration, changes in other processes such as fire regimes, nutrient cycling, and invasive plant proliferation remain more difficult to reverse at larger landscape scales.
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Restoration of Native Hawaiian Dryland Forest at Auwahi, Maui
Medieros, Arthur C.; vonAllmen, Erica
2006-01-01
BACKGROUND The powerful volcanoes that formed the high islands of the Hawaiian archipelago block northeasterly tradewinds, creating wet, windward rain forests and much drier, leeward forests. Dryland forests in Hawai'i receive only about 20 inches of rain a year. However, the trees in these forests intercept fog and increase ground moisture levels, thereby enabling these seemingly inhospitable habitats to support a diverse assemblage of plants and animals. Dryland forests of the Hawaiian Islands, like those worldwide, have been heavily impacted by humans both directly and indirectly. Less than 10% of Hawai'i's original dryland forest habitat remains. These forests have been severely impacted by urban development, ranching and agriculture, and invasive species. In particular, browsing animals and alien grasses have caused significant damage. Feral ungulates, including goats, sheep, cattle, and pigs, consume sensitive plants. Alien grasses have become dominant in the understory in many dryland habitats. In addition, these introduced grasses are fire-adapted and have increased the incidence of wildfire in these ecosystems. Native Hawaiian plants did not evolve with frequent fires or mammalian herbivores and typically do not survive well under these pressures.
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NASA Astrophysics Data System (ADS)
Masiello, C. A.; Hockaday, W. C.; Gallagher, M. E.; Calligan, L.
2009-12-01
Ecosystem net primary productivity (NPP) can vary significantly with annual variations in precipitation and temperature. These climate variations can also drive changes in plant carbon allocation patterns. Shifting allocation patterns can lead to variation in net ecosystem biochemical stocks (e.g. kg cellulose, lignin, protein, and lipid/ha), which can in turn lead to shifts in ecosystem oxidative ratio (OR). OR is the molar ratio of O2 released : CO2 fixed during biosynthesis. Major plant biochemicals vary substantially in oxidative ratio, ranging from average organic acid OR values of 0.75 to average lipid OR values of 1.37 (Masiello et al., 2008). OR is a basic property of ecosystem biochemistry, and is also an essential variable needed to constrain the size of the terrestrial biospheric carbon sink (Keeling et al., 1996). OR is commonly assumed to be 1.10 (e.g. Prentice et al., 2001), but small variations in net ecosystem OR can drive large errors in estimates of the size of the terrestrial carbon sink (Randerson et al., 2006). We hypothesized that interannual changes in climate may drive interannual variation in ecosystem OR values. Working at Kellogg Biological Station NSF LTER, we measured the annual average OR of coniferous and deciduous forests, an early successional forest, and croplands under both corn and soy. There are clear distinctions between individual ecosystems (e.g., the soy crops have a higher OR than the corn crops, and the coniferous forests have a higher OR than the deciduous forests), but the ecosystems themselves retained remarkably constant annual OR values between 1998 and 2008.
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Unearthing Secrets of the Forest
Beldin, Sarah I.; Perakis, Steven S.
2009-01-01
Forests are a defining feature for large areas of the Pacific northwestern United States from northern California to Alaska. Coniferous temperate rainforests in the western Cascade and coastal mountain ranges are appreciated for their aesthetic value and abundant natural resources. Few people recognize the riches beneath the forest floor; yet, soil is a key ecosystem component that makes each type of forest unique. Soils harbor immense biological diversity and control the release of water and nutrients that support life above ground. Understanding how carbon and nutrients cycle in forests, known as forest biogeochemistry, is crucial for evaluating forest productivity, composition, diversity, and change. At the U.S. Geological Survey (USGS) Forest and Rangeland Ecosystem Science Center, research in the Terrestrial Ecosystems Laboratory focuses on nutrient cycling in five themes: climate change, nutrition and sustainability, fire effects, restoration, and forest-stream linkages. This research is essential to understand the entire forest ecosystem and to use the best science available to make informed policy and management decisions.
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ERIC Educational Resources Information Center
Liljeström, Anu; Enkenberg, Jorma; Vanninen, Petteri; Vartiainen, Henriikka; Pöllänen, Sinikka
2014-01-01
This paper discusses the OpenForest portal and its related multidisciplinary learning project. The OpenForest portal is an open learning environment and ecosystem, in which students can participate in co-developing and co-creating practices. The aim of the OpenForest ecosystem is to create an extensive interactive network of diverse learning…
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Forest restoration, biodiversity and ecosystem functioning.
Aerts, Raf; Honnay, Olivier
2011-11-24
Globally, forests cover nearly one third of the land area and they contain over 80% of terrestrial biodiversity. Both the extent and quality of forest habitat continue to decrease and the associated loss of biodiversity jeopardizes forest ecosystem functioning and the ability of forests to provide ecosystem services. In the light of the increasing population pressure, it is of major importance not only to conserve, but also to restore forest ecosystems. Ecological restoration has recently started to adopt insights from the biodiversity-ecosystem functioning (BEF) perspective. Central is the focus on restoring the relation between biodiversity and ecosystem functioning. Here we provide an overview of important considerations related to forest restoration that can be inferred from this BEF-perspective. Restoring multiple forest functions requires multiple species. It is highly unlikely that species-poor plantations, which may be optimal for above-ground biomass production, will outperform species diverse assemblages for a combination of functions, including overall carbon storage and control over water and nutrient flows. Restoring stable forest functions also requires multiple species. In particular in the light of global climatic change scenarios, which predict more frequent extreme disturbances and climatic events, it is important to incorporate insights from the relation between biodiversity and stability of ecosystem functioning into forest restoration projects. Rather than focussing on species per se, focussing on functional diversity of tree species assemblages seems appropriate when selecting tree species for restoration. Finally, also plant genetic diversity and above - below-ground linkages should be considered during the restoration process, as these likely have prominent but until now poorly understood effects at the level of the ecosystem. The BEF-approach provides a useful framework to evaluate forest restoration in an ecosystem functioning context, but it also highlights that much remains to be understood, especially regarding the relation between forest functioning on the one side and genetic diversity and above-ground-below-ground species associations on the other. The strong emphasis of the BEF-approach on functional rather than taxonomic diversity may also be the beginning of a paradigm shift in restoration ecology, increasing the tolerance towards allochthonous species.
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Disturbance dynamics and ecosystem-based forest management
Kalev Jogiste; W. Keith Moser; Malle Mandre
2005-01-01
Ecosystem-based management is intended to balance ecological, social and economic values of sustainable resource management. The desired future state of forest ecosystem is usually defined through productivity, biodiversity, stability or other terms. However, ecosystem-based management may produce an unbalanced emphasis on different components. Although ecosystem-based...
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Managing forest ecosystems to conserve fungus diversity and sustain wild mushroom harvests.
D. Pilz; R. Molina
1996-01-01
Ecosystem management is the dominant paradigm for managing the forests of the Pacific Northwest. It integrates biological, ecological, geophysical, and silvicultural information to develop adaptive management practices that conserve biological diversity and maintain ecosystem functioning while meeting human needs for the sustainable production of forest products. Fungi...
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The forgotten stage of forest succession: early-successional ecosystems on forest sites
Mark E. Swanson; Jerry F. Franklin; Robert L. Beschta; Charles M. Crisafulli; Dominick A. DellaSala; Richard L. Hutto; David B. Lindenmayer; Frederick J. Swanson
2010-01-01
Early-successional forest ecosystems that develop after stand-replacing or partial disturbances are diverse in species, processes, and structure. Post-disturbance ecosystems are also often rich in biological legacies, including surviving organisms and organically derived structures, such as woody debris. These legacies and postdisturbance plant communities provide...
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Belowground ecosystems [chapter 9
Carole Coe Klopatek
1995-01-01
The USDA Forest Service defined ecosystem management as "an ecological approach to achieve multiple-use management of national forests and grasslands by blending the needs of people and environmental values in such a way that national forests and grasslands represent diverse, healthy, productive, and sustainable ecosystems" (June 4, 1992, letter from Chief FS...
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7 CFR 625.6 - Establishing priority for enrollment in HFRP.
Code of Federal Regulations, 2012 CFR
2012-01-01
... contribution of non-Federal funds; (6) Significance of forest ecosystem functions and values; (7) Estimated... place higher priority on certain forest ecosystems based regions of the State or multi-State area where... is essential to the successful restoration of the forest ecosystem and those adjacent landowners are...
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7 CFR 625.6 - Establishing priority for enrollment in HFRP.
Code of Federal Regulations, 2013 CFR
2013-01-01
... contribution of non-Federal funds; (6) Significance of forest ecosystem functions and values; (7) Estimated... place higher priority on certain forest ecosystems based regions of the State or multi-State area where... is essential to the successful restoration of the forest ecosystem and those adjacent landowners are...
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7 CFR 625.6 - Establishing priority for enrollment in HFRP.
Code of Federal Regulations, 2014 CFR
2014-01-01
... contribution of non-Federal funds; (6) Significance of forest ecosystem functions and values; (7) Estimated... place higher priority on certain forest ecosystems based regions of the State or multi-State area where... is essential to the successful restoration of the forest ecosystem and those adjacent landowners are...
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7 CFR 625.6 - Establishing priority for enrollment in HFRP.
Code of Federal Regulations, 2011 CFR
2011-01-01
... contribution of non-Federal funds; (6) Significance of forest ecosystem functions and values; (7) Estimated... place higher priority on certain forest ecosystems based regions of the State or multi-State area where... is essential to the successful restoration of the forest ecosystem and those adjacent landowners are...
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Forest Ecosystem services: Water resources
Thomas P. Holmes; James Vose; Travis Warziniack; Bill Holman
2017-01-01
Since the publication of the Millennium Ecosystem Assessment (MEA 2005), awareness has steadily grown regarding the importance of maintaining natural capital. Forest vegetation is a valuable source of natural capital, and the regulation of water quantity and quality is among the most important forest ecosystem services in many regions around the world. Changes in...
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Assessment and monitoring of forest ecosystem structure
Oscar A. Aguirre Calderón; Javier Jiménez Pérez; Horst Kramer
2006-01-01
Characterization of forest ecosystems structure must be based on quantitative indices that allow objective analysis of human influences or natural succession processes. The objective of this paper is the compilation of diverse quantitative variables to describe structural attributes from the arboreal stratum of the ecosystem, as well as different methods of forest...
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Busch, G; Lammel, G; Beese, F O; Feichter, J; Dentener, F J; Roelofs, G J
2001-01-01
A global assessment of the impact of the anthropogenic perturbation of the nitrogen and sulfur cycles on forest ecosystems is carried out for both the present-day [1980-1990] and for a projection into the future [2040-2050] under a scenario of economic development which represents a medium path of development according to expert guess [IPCC IS92a]. Results show that forest soils will receive considerably increasing loads of nitrogen and acid deposition and that deposition patterns are likely to change. The regions which are most prone to depletion of soils buffering capacity and supercritical nitrogen deposition are identified in the subtropical and tropical regions of South America and Southeast Asia apart from the well known 'hotspots' North-Eastern America and Central Europe. The forest areas likely to meet these two risks are still a minor fraction of the global forest ecosystems, though. But the bias between eutrophication and acidification will become greater and an enhanced growth triggered by the fertilizing effects of increasing nitrogen input cannot be balanced by the forest soils nutrient pools. Results show increasing loads into forest ecosystems which are likely to account for 46% higher acid loads and 36% higher nitrogen loads in relation to the 1980-1990 situation. Global background deposition of up to 5 kg N ha-1 a-1 will be exceeded at more than 25% of global forest ecosystems and at more than 50% of forest ecosystems on acid sensitive soils. More than 33% of forest ecosystems on acid sensitive soils will receive acid loads which exceeds their buffering capacity. About 25% of forest areas with exceeded acid loads will receive critical nitrogen loads.
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NASA Astrophysics Data System (ADS)
Branquinho, Cristina; Príncipe, Adriana; Nunes, Alice; Kobel, Melanie; Soares, Cristina; Pinho, Pedro
2016-04-01
The recent expansion of the semiarid climate to all the region of the south of Portugal and the growing impact of climate change demands local adaptation. The growth of the native forest represents a strategy at the ecosystem level to adapt to climate change since it increases resilience and increases also de delivery of ecosystem services such as the increment of organic matter in the soil, carbon and nitrogen, biodiversity, water infiltration, etc. Moreover decreases susceptibility to desertification. For that reason, large areas have been reforested in the south of Portugal with the native species holm oak and cork oak but with a low rate of effectiveness. Our goal in this work is to show how the cost-benefit relation of the actions intended to expand the forest of the Portuguese semiarid can be lowered by taking into account the microclimatic conditions and high spatial resolution management. The potential of forest regeneration was modelled at the local and regional level in the semiarid area using information concerning the Potential Solar Radiation. This model gives us the rate of native forest regeneration after a disturbance with high spatial resolution. Based on this model the territory was classified in: i) easy regeneration areas; ii) areas with the need of assisted reforestation, using methods that increase water and soil conservation; iii) areas of difficult reforestation because of the costs. Additionally a summary of the success of reforestations was made in the historical semiarid since the 60s based on the evaluation of a series of case studies, where we quantified the ecosystem services currently delivered by the reforested ecosystems. Acknowledgement: Programa Adapt: financed by EEA Grants and Fundo Português de Carbono
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NASA Astrophysics Data System (ADS)
Broich, Mark
Humid tropical forest cover loss is threatening the sustainability of ecosystem goods and services as vast forest areas are rapidly cleared for industrial scale agriculture and tree plantations. Despite the importance of humid tropical forest in the provision of ecosystem services and economic development opportunities, the spatial and temporal distribution of forest cover loss across large areas is not well quantified. Here I improve the quantification of humid tropical forest cover loss using two remote sensing-based methods: sampling and wall-to-wall mapping. In all of the presented studies, the integration of coarse spatial, high temporal resolution data with moderate spatial, low temporal resolution data enable advances in quantifying forest cover loss in the humid tropics. Imagery from the Moderate Resolution Imaging Spectroradiometer (MODIS) are used as the source of coarse spatial resolution, high temporal resolution data and imagery from the Landsat Enhanced Thematic Mapper Plus (ETM+) sensor are used as the source of moderate spatial, low temporal resolution data. In a first study, I compare the precision of different sampling designs for the Brazilian Amazon using the annual deforestation maps derived by the Brazilian Space Agency for reference. I show that sampling designs can provide reliable deforestation estimates; furthermore, sampling designs guided by MODIS data can provide more efficient estimates than the systematic design used for the United Nations Food and Agricultural Organization Forest Resource Assessment 2010. Sampling approaches, such as the one demonstrated, are viable in regions where data limitations, such as cloud contamination, limit exhaustive mapping methods. Cloud-contaminated regions experiencing high rates of change include Insular Southeast Asia, specifically Indonesia and Malaysia. Due to persistent cloud cover, forest cover loss in Indonesia has only been mapped at a 5-10 year interval using photo interpretation of single best Landsat images. Such an approach does not provide timely results, and cloud cover reduces the utility of map outputs. In a second study, I develop a method to exhaustively mine the recently opened Landsat archive for cloud-free observations and automatically map forest cover loss for Sumatra and Kalimantan for the 2000-2005 interval. In a comparison with a reference dataset consisting of 64 Landsat sample blocks, I show that my method, using per pixel time-series, provides more accurate forest cover loss maps for multiyear intervals than approaches using image composites. In a third study, I disaggregate Landsat-mapped forest cover loss, mapped over a multiyear interval, by year using annual forest cover loss maps generated from coarse spatial, high temporal resolution MODIS imagery. I further disaggregate and analyze forest cover loss by forest land use, and provinces. Forest cover loss trends show high spatial and temporal variability. These results underline the importance of annual mapping for the quantification of forest cover loss in Indonesia, specifically in the light of the developing Reducing Emissions from Deforestation and Forest Degradation in Developing Countries policy framework (REDD). All three studies highlight the advances in quantifying forest cover loss in the humid tropics made by integrating coarse spatial, high temporal resolution data with moderate spatial, low temporal resolution data. The three methods presented can be combined into an integrated monitoring strategy.
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Latent heat exchange in the boreal and arctic biomes.
Kasurinen, Ville; Alfredsen, Knut; Kolari, Pasi; Mammarella, Ivan; Alekseychik, Pavel; Rinne, Janne; Vesala, Timo; Bernier, Pierre; Boike, Julia; Langer, Moritz; Belelli Marchesini, Luca; van Huissteden, Ko; Dolman, Han; Sachs, Torsten; Ohta, Takeshi; Varlagin, Andrej; Rocha, Adrian; Arain, Altaf; Oechel, Walter; Lund, Magnus; Grelle, Achim; Lindroth, Anders; Black, Andy; Aurela, Mika; Laurila, Tuomas; Lohila, Annalea; Berninger, Frank
2014-11-01
In this study latent heat flux (λE) measurements made at 65 boreal and arctic eddy-covariance (EC) sites were analyses by using the Penman-Monteith equation. Sites were stratified into nine different ecosystem types: harvested and burnt forest areas, pine forests, spruce or fir forests, Douglas-fir forests, broadleaf deciduous forests, larch forests, wetlands, tundra and natural grasslands. The Penman-Monteith equation was calibrated with variable surface resistances against half-hourly eddy-covariance data and clear differences between ecosystem types were observed. Based on the modeled behavior of surface and aerodynamic resistances, surface resistance tightly control λE in most mature forests, while it had less importance in ecosystems having shorter vegetation like young or recently harvested forests, grasslands, wetlands and tundra. The parameters of the Penman-Monteith equation were clearly different for winter and summer conditions, indicating that phenological effects on surface resistance are important. We also compared the simulated λE of different ecosystem types under meteorological conditions at one site. Values of λE varied between 15% and 38% of the net radiation in the simulations with mean ecosystem parameters. In general, the simulations suggest that λE is higher from forested ecosystems than from grasslands, wetlands or tundra-type ecosystems. Forests showed usually a tighter stomatal control of λE as indicated by a pronounced sensitivity of surface resistance to atmospheric vapor pressure deficit. Nevertheless, the surface resistance of forests was lower than for open vegetation types including wetlands. Tundra and wetlands had higher surface resistances, which were less sensitive to vapor pressure deficits. The results indicate that the variation in surface resistance within and between different vegetation types might play a significant role in energy exchange between terrestrial ecosystems and atmosphere. These results suggest the need to take into account vegetation type and phenology in energy exchange modeling. © 2014 John Wiley & Sons Ltd.
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E.M. Goheen; S.J. Frankel
2009-01-01
The fourth meeting of the International Union of Forest Research Organizations (IUFRO) Working Party S07.02.09, Phytophthoras in Forests and Natural Ecosystems provided a forum for current research on Phytophthora species worldwide. Seventy-eight submissions describing papers and posters on recent developments in Phytophthora diseases of trees and natural ecosystems in...
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Restoring Forested Wetland Ecosystems
John A. Stanturf; Emile S. Gardiner; Melvin L. Warren
2003-01-01
Forests as natural systems are intrinsically linked to the sustainability of fresh-water systems. Efforts worldwide to restore forest ecosystems seek to counteract centuries of forest conversion to agriculture and other uses. Afforestation, the practice of regenerating forests on land deforested for agriculture or other uses, is occurring at an intense pace in the...
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Bulgarian Rila mountain forest ecosystems study site: site description and SO42-, NO3- deposition
Karl Zeller; Christo Bojinov; Evgeny Donev; Nedialko Nikolov
1998-01-01
Bulgaria's forest ecosystems (31 percent of the country's area) are considered vulnerable to dry and wet pollution deposition. Coniferous forests that cover one-third of the total forest land are particularly sensitive to pollution loads. The USDA Forest Service, Sofia University, and the Bulgarian Forest Research Institute (FRI) established a cooperative...
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Carbon Budget and its Dynamics over Northern Eurasia Forest Ecosystems
NASA Astrophysics Data System (ADS)
Shvidenko, Anatoly; Schepaschenko, Dmitry; Kraxner, Florian; Maksyutov, Shamil
2016-04-01
The presentation contains an overview of recent findings and results of assessment of carbon cycling of forest ecosystems of Northern Eurasia. From a methodological point of view, there is a clear tendency in understanding a need of a Full and Verified Carbon Account (FCA), i.e. in reliable assessment of uncertainties for all modules and all stages of FCA. FCA is considered as a fuzzy (underspecified) system that supposes a system integration of major methods of carbon cycling study (land-ecosystem approach, LEA; process-based models; eddy covariance; and inverse modelling). Landscape-ecosystem approach 1) serves for accumulation of all relevant knowledge of landscape and ecosystems; 2) for strict systems designing the account, 3) contains all relevant spatially distributed empirical and semi-empirical data and models, and 4) is presented in form of an Integrated Land Information System (ILIS). The ILIS includes a hybrid land cover in a spatially and temporarily explicit way and corresponding attributive databases. The forest mask is provided by utilizing multi-sensor remote sensing data, geographically weighed regression and validation within GEO-wiki platform. By-pixel parametrization of forest cover is based on a special optimization algorithms using all available knowledge and information sources (data of forest inventory and different surveys, observations in situ, official statistics of forest management etc.). Major carbon fluxes within the LEA (NPP, HR, disturbances etc.) are estimated based on fusion of empirical data and aggregations with process-based elements by sets of regionally distributed models. Uncertainties within LEA are assessed for each module and at each step of the account. Within method results of LEA and corresponding uncertainties are harmonized and mutually constrained with independent outputs received by other methods based on the Bayesian approach. The above methodology have been applied to carbon account of Russian forests for 2000-2012. It has been shown that the Net Ecosystem Carbon Budget (NECB) of Russian forests for this period was in range of 0.5-0.7 Pg C yr-1 with a slight negative trend during the period due to acceleration of disturbance regimes and negative impacts of weather extremes (heat waves etc.). Uncertainties of the FCA for individual years were estimated at about 25% (CI 0.9). It has been shown that some models (e.g. majority of DGVMs) do not describe some processes on permafrost satisfactory while results of applications of ensembles of inverse models on average are closed to empirical assessments. A most important conclusion from this experience is that future improvements of knowledge of carbon cycling of Northern Eurasia forests requires development of an integrated observing system as a unified information background, as well as systems methodological improvements of all methods of cognition of carbon cycling.
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Managing redwood ecosystems using Sudden Oak Death as a silvicultural tool
Frederick D. Euphrat
2015-01-01
In response to the wave of sudden oak death (SOD), caused by Phytophthora ramorum, sweeping the redwood forest ecosystems of California's North Coast, the role of foresters and other ecosystem managers is being tested. On Bear Flat Tree Farm, near Healdsburg, California, Forest, Soil & Water, Inc. (FSW) has conducted a multi-year,...
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Carbon allocation in forest ecosystems
Creighton M. Litton; James W. Raich; Michael G. Ryan
2007-01-01
Carbon allocation plays a critical role in forest ecosystem carbon cycling. We reviewed existing literature and compiled annual carbon budgets for forest ecosystems to test a series of hypotheses addressing the patterns, plasticity, and limits of three components of allocation: biomass, the amount of material present; flux, the flow of carbon to a component per unit...
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Using DCOM to support interoperability in forest ecosystem management decision support systems
W.D. Potter; S. Liu; X. Deng; H.M. Rauscher
2000-01-01
Forest ecosystems exhibit complex dynamics over time and space. Management of forest ecosystems involves the need to forecast future states of complex systems that are often undergoing structural changes. This in turn requires integration of quantitative science and engineering components with sociopolitical, regulatory, and economic considerations. The amount of data...
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Drought stress and carbon uptake in an Amazon forest measured with spaceborne imaging spectroscopy
Asner, Gregory P.; Nepstad, Daniel; Cardinot, Gina; Ray, David
2004-01-01
Amazônia contains vast stores of carbon in high-diversity ecosystems, yet this region undergoes major changes in precipitation affecting land use, carbon dynamics, and climate. The extent and structural complexity of Amazon forests impedes ground studies of ecosystem functions such as net primary production (NPP), water cycling, and carbon sequestration. Traditional modeling and remote-sensing approaches are not well suited to tropical forest studies, because (i) biophysical mechanisms determining drought effects on canopy water and carbon dynamics are poorly known, and (ii) remote-sensing metrics of canopy greenness may be insensitive to small changes in leaf area accompanying drought. New spaceborne imaging spectroscopy may detect drought stress in tropical forests, helping to monitor forest physiology and constrain carbon models. We combined a forest drought experiment in Amazônia with spaceborne imaging spectrometer measurements of this area. With field data on rainfall, soil water, and leaf and canopy responses, we tested whether spaceborne hyperspectral observations quantify differences in canopy water and NPP resulting from drought stress. We found that hyperspectral metrics of canopy water content and light-use efficiency are highly sensitive to drought. Using these observations, forest NPP was estimated with greater sensitivity to drought conditions than with traditional combinations of modeling, remote-sensing, and field measurements. Spaceborne imaging spectroscopy will increase the accuracy of ecological studies in humid tropical forests. PMID:15071182
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Veldman, Joseph W.; Mattingly, W. Brett; Brudvig, Lars A.
Although savanna trees and forest trees are thought to represent distinct functional groups with different effects on ecosystem processes, few empirical studies have examined these effects. In particular, it remains unclear if savanna and forest trees differ in their ability to coexist with understory plants, which comprise the majority of plant diversity in most savannas. We used structural equation modeling (SEM) and data from 157 sites across three locations in the southeastern United States to understand the effects of broadleaf savanna trees, broadleaf forest trees, and pine trees on savanna understory plant communities. After accounting for underlying gradients in firemore » frequency and soil moisture, abundances (i.e., basal area and stem density) of forest trees and pines, but not savanna trees, were negatively correlated with the cover and density (i.e., local-scale species richness) of C4 graminoid species, a defining savanna understory functional group that is linked to ecosystem flammability. In analyses of the full understory community, abundances of trees from all functional groups were negatively correlated with species density and cover. For both the C4 and full communities, fire frequency promoted understory plants directly, and indirectly by limiting forest tree abundance. There was little indirect influence of fire on the understory mediated through savanna trees and pines, which are more fire tolerant than forest trees. We conclude that tree functional identity is an important factor that influences overstory tree relationships with savanna understory plant communities. In particular, distinct relationships between trees and C4 graminoids have implications for grass-tree coexistence and vegetation-fire feedbacks that maintain savanna environments and their associated understory plant diversity.« less
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NASA Astrophysics Data System (ADS)
Din, Abdullah Muhaimin Mohammad; Yaakop, Salmah; Hazmi, Izfa Riza
2015-09-01
Dung beetles has known for its bioindicator characteristic. Sensitive towards forest disturbance, dung beetles population and diversity will be less in disturbed and modified area. The objective of this study is to evaluate the diversity and distribution of dung beetles in different type of ecosystems in Peninsular Malaysia. Fifteen baited pitfall traps aligned in three transects were used in this study. Samples were collected after 24 h and repeated three time collections and identified afterwards. Two ecosystem types were selected, which are forested and agricultural ecosystem (livestock and plantation). A total of 4249 individuals, 47 species, in 11 genera was successfully collected from all localities. The H' index for Fraser Hill, Langkawi, Bangi Reserve Forest, Selangor (HSB), Sungkai Reserve Forest, Perak (SRF), Chini Lake, Bera Lake, chicken farm, goat farm, Longan plantation, and palm oil plantation were 1.58, 1.74, 2.17, 2.63, 1.80, 1.52, 1.63, 0.46, 0.00 and 1.98 respectively.Forest ecosystem, SRF shows the highest abundance (1486 individuals) and diversity, while for agricultural ecosystem,palm oil plantation shows the highest with 273 individuals and 16 species. Based onDetrended Correspondence Analysis (DCA) shows two groups that separate forest ecosystem with the agricultural ecosystem, with palm oil is the nearest to the forest. Palm oil ecosystem can sustain a dung beetles population due to the area can provide the requirements for the dung beetles to survive, such as food which comes from local domestic cows, shade from sunlight provide by the palm oil trees, and ground cover from small plants and shrubs.Even though modified ecosystem should have lower diversity of dung beetles, but some factors must be measured as well in order to have a better point of view.
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Rates and drivers of mangrove deforestation in Southeast Asia, 2000-2012.
Richards, Daniel R; Friess, Daniel A
2016-01-12
The mangrove forests of Southeast Asia are highly biodiverse and provide multiple ecosystem services upon which millions of people depend. Mangroves enhance fisheries and coastal protection, and store among the highest densities of carbon of any ecosystem globally. Mangrove forests have experienced extensive deforestation owing to global demand for commodities, and previous studies have identified the expansion of aquaculture as largely responsible. The proportional conversion of mangroves to different land use types has not been systematically quantified across Southeast Asia, however, particularly in recent years. In this study we apply a combined geographic information system and remote sensing method to quantify the key proximate drivers (i.e., replacement land uses) of mangrove deforestation in Southeast Asia between 2000 and 2012. Mangrove forests were lost at an average rate of 0.18% per year, which is lower than previously published estimates. In total, more than 100,000 ha of mangroves were removed during the study period, with aquaculture accounting for 30% of this total forest change. The rapid expansion of rice agriculture in Myanmar, and the sustained conversion of mangroves to oil palm plantations in Malaysia and Indonesia, are identified as additional increasing and under-recognized threats to mangrove ecosystems. Our study highlights frontiers of mangrove deforestation in the border states of Myanmar, on Borneo, and in Indonesian Papua. To implement policies that conserve mangrove forests across Southeast Asia, it is essential to consider the national and subnational variation in the land uses that follow deforestation.
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Rates and drivers of mangrove deforestation in Southeast Asia, 2000–2012
Richards, Daniel R.; Friess, Daniel A.
2016-01-01
The mangrove forests of Southeast Asia are highly biodiverse and provide multiple ecosystem services upon which millions of people depend. Mangroves enhance fisheries and coastal protection, and store among the highest densities of carbon of any ecosystem globally. Mangrove forests have experienced extensive deforestation owing to global demand for commodities, and previous studies have identified the expansion of aquaculture as largely responsible. The proportional conversion of mangroves to different land use types has not been systematically quantified across Southeast Asia, however, particularly in recent years. In this study we apply a combined geographic information system and remote sensing method to quantify the key proximate drivers (i.e., replacement land uses) of mangrove deforestation in Southeast Asia between 2000 and 2012. Mangrove forests were lost at an average rate of 0.18% per year, which is lower than previously published estimates. In total, more than 100,000 ha of mangroves were removed during the study period, with aquaculture accounting for 30% of this total forest change. The rapid expansion of rice agriculture in Myanmar, and the sustained conversion of mangroves to oil palm plantations in Malaysia and Indonesia, are identified as additional increasing and under-recognized threats to mangrove ecosystems. Our study highlights frontiers of mangrove deforestation in the border states of Myanmar, on Borneo, and in Indonesian Papua. To implement policies that conserve mangrove forests across Southeast Asia, it is essential to consider the national and subnational variation in the land uses that follow deforestation. PMID:26712025
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Zheng, Jingming; Jiang, Fengqi; Zeng, Dehui
2003-06-01
To realize the sustainable management of forest ecosystems, we should explicitly clarify the types and differences of the ecosystem services provided by different ecosystems under different conditions, with rethinking about the value of forest ecosystems; then solid management strategies and measurements will be enacted and applied to achieve the objects. The broad-leaved Korean pine forest (BLKPF) in Changbai Mountain is a unique and important forest type in China, owing to its many important ecosystem services such as preventing soil erosion, regulating climates, nutrient cycling, providing wood and non-timber forest products, etc. This paper is a preliminary study on the management strategy of BLKPF on the basis of analyzing the characters of the ecosystems and the relative importance of services they provided in this region. Based on the latest research of ecosystem services of BLKPF in Changbai Mountain, an idea of eco-value level (EVL) was introduced, and accordingly, management strategies were summarized by adopting the advanced theories in ecosystem management science and by analyzing field survey data. EVL means the relative amount of the value of ecosystem services provided by certain ecosystem, which can indicate the difference between services in given objects. The EVL classification of BLKPF implies the relative amount of the eco-value of different ecosystems including virgin forest, secondary forest, forest with human disturbance, and man-made forest in the clear-cutting sites. Analytical Hierarchical Processing method was used to formulate the equation for EVL index. Eight factors, namely, slope, soil depth, stability of soil maternal material, coverage of above-ground canopy, species diversity, regeneration rate of the stand, life span of dominant tree species, and intensity of human disturbance were chosen to build the formula. These factors belonged to three aspects affecting ecosystem services including the physical environment, community, and disturbance regime, and their selection and scaling were based on the previous studies on the BLKPF. The equation of EVL index (EI) was expressed as: EI = 0.542A1 + 0.171A2 + 0.072A3 + 0.067B1 + 0.043B2 + 0.014B3 + 0.010B4 + 0.081C1. According to the range of EI, ecosystems were classified into three types: low EVL type with EI from 1.000 to 1.874, medium EVL type with EI 1.874-2.749, and high EVL type with EI 2.749-3.623. Typical plots were surveyed and scaled with EI, and the predominant characters of each EVL type were summarized. Most forests of high EVL type were those in sites at high risk of soil erosion and hard to recover after disrupted. Forests of medium EVL type were those with worse community structure and composition, and were disturbed by human activities in relative steep sites. Forest of low EVL type were those in plane site with serious disruption or some young man-made stands. Based on the analyses of the characters of these three types, different management strategies were put forward. For high EVL type forest, strictly protection is most important to maintain the forest in natural succession and its eco-services. For medium EVL type forest, the key points of management are restoring their health and vigor by regulating their composition and structure in a seminatural way. For low EVL type forest, some area could be used to extensive exploration for economic benefits, and the rests should be reconstructed towards the original stand in composition and structure, based on the 'shadow ecosystem' in a close-to-nature way to promote the capacity of providing more eco-services.
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A review of impacts by invasive exotic plants on forest ecosystem services
Kevin Devine; Songlin Fei
2011-01-01
Many of our forest ecosystems are at risk due to the invasion of exotic invasive plant species. Invasive plant species pose numerous threats to ecosystems by decreasing biodiversity, deteriorating ecosystem processes, and degrading ecosystem services. Literature on Kentucky's most invasive exotic plant species was examined to understand their potential impacts on...
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Diversity-dependent temporal divergence of ecosystem functioning in experimental ecosystems
Nathaly R. Guerrero-Ramírez; Dylan Craven; Peter B. Reich; John J. Ewel; Forest Isbell; Julia Koricheva; John A. Parrotta; Harald Auge; Heather E. Erickson; David I. Forrester; Andy Hector; Jasmin Joshi; Florencia Montagnini; Cecilia Palmborg; Daniel Piotto; Catherine Potvin; Christiane Roscher; Jasper van Ruijven; David Tilman; Brian Wilsey; Nico Eisenhauer
2017-01-01
The effects of biodiversity on ecosystem functioning generally increase over time, but the underlying processes remain unclear. Using 26 long-term grassland and forest experimental ecosystems, we demonstrate that biodiversityâecosystem functioning relationships strengthen mainly by greater increases in functioning in high-diversity communities in grasslands and forests...
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Robles, Hugo; Martin, Kathy
2014-01-01
Through physical state changes in biotic or abiotic materials, ecosystem engineers modulate resource availability to other organisms and are major drivers of evolutionary and ecological dynamics. Understanding whether and how ecosystem engineers are interchangeable for resource users in different habitats is a largely neglected topic in ecosystem engineering research that can improve our understanding of the structure of communities. We addressed this issue in a cavity-nest web (1999–2011). In aspen groves, the presence of mountain bluebird (Sialia currucoides) and tree swallow (Tachycineta bicolour) nests was positively related to the density of cavities supplied by northern flickers (Colaptes auratus), which provided the most abundant cavities (1.61 cavities/ha). Flickers in aspen groves provided numerous nesting cavities to bluebirds (66%) and swallows (46%), despite previous research showing that flicker cavities are avoided by swallows. In continuous mixed forests, however, the presence of nesting swallows was mainly related to cavity density of red-naped sapsuckers (Sphyrapicus nuchalis), which provided the most abundant cavities (0.52 cavities/ha), and to cavity density of hairy woodpeckers (Picoides villosus), which provided few (0.14 cavities/ha) but high-quality cavities. Overall, sapsuckers and hairy woodpeckers provided 86% of nesting cavities to swallows in continuous forests. In contrast, the presence of nesting bluebirds in continuous forests was associated with the density of cavities supplied by all the ecosystem engineers. These results suggest that (i) habitat type may mediate the associations between ecosystem engineers and resource users, and (ii) different ecosystem engineers may be interchangeable for resource users depending on the quantity and quality of resources that each engineer supplies in each habitat type. We, therefore, urge the incorporation of the variation in the quantity and quality of resources provided by ecosystem engineers across habitats into models that assess community dynamics to improve our understanding of the importance of ecosystem engineers in shaping ecological communities. PMID:24587211
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Robles, Hugo; Martin, Kathy
2014-01-01
Through physical state changes in biotic or abiotic materials, ecosystem engineers modulate resource availability to other organisms and are major drivers of evolutionary and ecological dynamics. Understanding whether and how ecosystem engineers are interchangeable for resource users in different habitats is a largely neglected topic in ecosystem engineering research that can improve our understanding of the structure of communities. We addressed this issue in a cavity-nest web (1999-2011). In aspen groves, the presence of mountain bluebird (Sialia currucoides) and tree swallow (Tachycineta bicolour) nests was positively related to the density of cavities supplied by northern flickers (Colaptes auratus), which provided the most abundant cavities (1.61 cavities/ha). Flickers in aspen groves provided numerous nesting cavities to bluebirds (66%) and swallows (46%), despite previous research showing that flicker cavities are avoided by swallows. In continuous mixed forests, however, the presence of nesting swallows was mainly related to cavity density of red-naped sapsuckers (Sphyrapicus nuchalis), which provided the most abundant cavities (0.52 cavities/ha), and to cavity density of hairy woodpeckers (Picoides villosus), which provided few (0.14 cavities/ha) but high-quality cavities. Overall, sapsuckers and hairy woodpeckers provided 86% of nesting cavities to swallows in continuous forests. In contrast, the presence of nesting bluebirds in continuous forests was associated with the density of cavities supplied by all the ecosystem engineers. These results suggest that (i) habitat type may mediate the associations between ecosystem engineers and resource users, and (ii) different ecosystem engineers may be interchangeable for resource users depending on the quantity and quality of resources that each engineer supplies in each habitat type. We, therefore, urge the incorporation of the variation in the quantity and quality of resources provided by ecosystem engineers across habitats into models that assess community dynamics to improve our understanding of the importance of ecosystem engineers in shaping ecological communities.
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The 2008 South China Freeze and its Impact on the Forests
NASA Astrophysics Data System (ADS)
Zhou, B.; Ai, C.; Wang, Y.; Li, Z.; Cao, Y.; Wang, X.
2008-12-01
An unprecedented calamity caused by snow and freezing rain occurred in South China in 2008. This freeze was closely related to the La Nina phenomenon according to a report from the World Meteorological Organization. The freeze stroke 19 provinces in China, and damaged forests of 19.33 million ha with a standing volume loss of 371 million m3. It is estimated that the direct economic loss in the form of destroyed forests is over $8 billion. The indirect loss in the form of impaired ecological functions, such as water and soil conservation, water resources conservancy, biodiversity and forest carbon pool etc is enormous. The calamity of snow and freezing rain affected the structure and function of forest ecosystems. The snow load and freezing rain caused mechanical damage to the trees, with the species of Pinus massoniana, Cunninghamia lanceolata, Pinus elliottii and Phyllostachys pubescens etc. being the most seriously affected. The cold weather could also cause the physiological hurt to the trees. The change of the biotic components leads to the change of abiotic components in the ecosystems. The sunlight under the canopy was intensified due to the opening up of the canopy. The air temperature in the forest, the nutrient and microorganism in soil, the litterfall dynamic were also affected. The alteration of the forest ecosystem structure brought in the alteration of its functions. The damage of the ecosystem structure weakened the capacity of the water and soil conservation, water resources conservancy and reduced the biodiversity in forest ecosystems. Forest gaps allow more sunlight into the freeze-damaged ecosystem, inducing the invasion of more masculine species. The direction and progress of the community succession was therefore altered. At the same time, the freeze made a great impact on the stability and health of the forest ecosystem, increasing the potential risk of outbreak of forest fire and plant diseases/insect pests. Some suggestions on the rebuilding and recovery of damaged forest were given in this paper.
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Adapting forest to climate change in drylands: the Portuguese case-study
NASA Astrophysics Data System (ADS)
Branquinho, Cristina; Príncipe, Adriana; Nunes, Alice; Kobel, Melanie; Soares, Cristina; Vizinho, André; Serrano, Helena Cristina; Pinho, Pedro
2017-04-01
The recent expansion of the semiarid climate to all the region of the south of Portugal and the growing impact of climate change demands local adaptation. The growth of the native forest represents a strategy at the ecosystem level to adapt to climate change since it increases resilience and increases also de delivery of ecosystem services such as the increment of organic matter in the soil, carbon and nitrogen, biodiversity, water infiltration, etc. Moreover, decreases susceptibility to desertification. For that reason, large areas have been reforested in the south of Portugal with the native species holm oak and cork oak but with a low rate of effectiveness. Our goal in this work is to show how the cost-benefit relation of the actions intended to expand the forest of the Portuguese semiarid can be lowered by taking into account the microclimatic conditions and high spatial resolution management. The potential of forest regeneration was modelled at the local and regional level in the semiarid area using information concerning the Potential Solar Radiation. This model gives us the rate of native forest regeneration after a disturbance with high spatial resolution. Based on this model the territory was classified in: i) easy regeneration areas; ii) areas with the need of assisted reforestation, using methods that increase water and soil conservation; iii) areas of difficult reforestation because of the costs. Additionally, a summary of the success of reforestations was made in the historical semiarid since the 60s based on the evaluation of a series of case studies, where we quantified the ecosystem services currently delivered by the reforested ecosystems. We will discuss and propose a strategy for forests to adapt to climate change scenario in dryland Portugal. Acknowledgement: Programa Adapt: financed by EEA Grants and Fundo Português de Carbono and by FCT-MEC project PTDC/AAG-GLO/0045/2014.
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Temporal evolution of carbon budgets of the Appalachian forests in the U.S. from 1972 to 2000
Liu, J.; Liu, S.; Loveland, Thomas R.
2006-01-01
Estimating dynamic terrestrial ecosystem carbon (C) sources and sinks over large areas is difficult. The scaling of C sources and sinks from the field level to the regional level has been challenging due to the variations of climate, soil, vegetation, and disturbances. As part of an effort to estimate the spatial, temporal, and sectional dimensions of the United States C sources and sinks (the U.S. Carbon Trends Project), this study estimated the forest ecosystem C sequestration of the Appalachian region (186,000 km2) for the period of 1972–2000 using the General Ensemble Biogeochemical Modeling System (GEMS) that has a strong capability of assimilating land use and land cover change (LUCC) data. On 82 sampling blocks in the Appalachian region, GEMS used sequential 60 m resolution land cover change maps to capture forest stand-replacing events and used forest inventory data to estimate non-stand-replacing changes. GEMS also used Monte Carlo approaches to deal with spatial scaling issues such as initialization of forest age and soil properties. Ensemble simulations were performed to incorporate the uncertainties of input data. Simulated results show that from 1972 to 2000 the net primary productivity (NPP), net ecosystem productivity (NEP), and net biome productivity (NBP) averaged 6.2 Mg C ha−1 y−1 (±1.1), 2.2 Mg C ha−1 y−1 (±0.6), and 1.8 Mg C ha−1 y−1(±0.6), respectively. The inter-annual variability was driven mostly by climate. Detailed C budgets for the year 2000 were also calculated. Within a total 148,000 km2 forested area, average forest ecosystem C density was estimated to be 186 Mg C ha−1 (±20), of which 98 Mg C ha−1 (±12) was in biomass and 88 Mg C ha−1 (±13) was in litter and soil. The total simulated C stock of the Appalachian forests was estimated to be 2751 Tg C (±296), including 1454 Tg C (±178) in living biomass and 1297 Tg C (±192) in litter and soil. The total net C sequestration (i.e. NBP) of the forest ecosystem in 2000 was estimated to be 19.5 Tg C y−1 (±6.8).
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An assessment of forest ecosystem health in the Southwest
Cathy W. Dahms; Brian W. Geils
1997-01-01
This report documents an ecological assessment of forest ecosystem health in the Southwest. The assessment focuses at the regional level and mostly pertains to lands administered by the National Forest System. Information is presented for use by forest and district resource managers as well as collaborative partners in the stewardship of Southwestern forests. The...
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Missouri Ozark Forest Ecosystem Project: the experiment
Steven L. Sheriff
2002-01-01
Missouri Ozark Forest Ecosystem Project (MOFEP) is a unique experiment to learn about the impacts of management practices on a forest system. Three forest management practices (uneven-aged management, even-aged management, and no-harvest management) as practiced by the Missouri Department of Conservation were randomly assigned to nine forest management sites using a...
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Weiguo Liu; Conghe Song; Todd A. Schroeder; Warren B. Cohen
2008-01-01
Forest succession is an important ecological process that has profound biophysical, biological and biogeochemical implications in terrestrial ecosystems. Therefore, information on forest successional stages over an extensive forested landscape is crucial for us to understand ecosystem processes, such as carbon assimilation and energy interception. This study explored...
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Studies on Interpretive Structural Model for Forest Ecosystem Management Decision-Making
NASA Astrophysics Data System (ADS)
Liu, Suqing; Gao, Xiumei; Zen, Qunying; Zhou, Yuanman; Huang, Yuequn; Han, Weidong; Li, Linfeng; Li, Jiping; Pu, Yingshan
Characterized by their openness, complexity and large scale, forest ecosystems interweave themselves with social system, economic system and other natural ecosystems, thus complicating both their researches and management decision-making. According to the theories of sustainable development, hierarchy-competence levels, cybernetics and feedback, 25 factors have been chosen from human society, economy and nature that affect forest ecosystem management so that they are systematically analyzed via developing an interpretive structural model (ISM) to reveal their relationships and positions in the forest ecosystem management. The ISM consists of 7 layers with the 3 objectives for ecosystem management being the top layer (the seventh layer). The ratio between agricultural production value and industrial production value as the bases of management decision-making in forest ecosystems becomes the first layer at the bottom because it has great impacts on the values of society and the development trends of forestry, while the factors of climatic environments, intensive management extent, management measures, input-output ratio as well as landscape and productivity are arranged from the second to sixth layers respectively.
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Robert L. Deal; Paul Hennon; Richard O' Hanlon; David D' Amore
2014-01-01
There is increasing interest worldwide in managing forests to maintain or improve biodiversity, enhance ecosystem services and assure long-term sustainability of forest resources. An important goal of forest management is to increase stand diversity, provide wildlife habitat and improve forest species diversity. We synthesize results from natural spruce forests in...
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Ian D. Thompson; Kimiko Okabe; John A. Parrotta; David I. Forrester; Eckehard Brockerhoff; Hervé Jactel; Hisatomo Taki
2014-01-01
Planted forests are increasingly contributing wood products and other ecosystem services at a global scale. These forests will be even more important as carbon markets develop and REDD-plus forest programs (forests used specifically to reduce atmospheric emissions of CO2 through deforestation and forest degradation) become common. Restoring degraded and deforested...
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Modeling the temporal dynamics of nonstructural carbohydrate pools in forest trees
DOE Office of Scientific and Technical Information (OSTI.GOV)
Richardson, Andrew D.
Trees store carbohydrates, in the form of sugars and starch, as reserves to be used to power both future growth as well as to support day-to-day metabolic functions. These reserves are particularly important in the context of how trees cope with disturbance and stress—for example, as related to pest outbreaks, wind or ice damage, and extreme climate events. In this project, we measured the size of carbon reserves in forest trees, and determined how quickly these reserves are used and replaced—i.e., their “turnover time”. Our work was conducted at Harvard Forest, a temperate deciduous forest in central Massachusetts. Through fieldmore » sampling, laboratory-based chemical analyses, and allometric modeling, we scaled these measurements up to whole-tree NSC budgets. We used these data to test and improve computer simulation models of carbon flow through forest ecosystems. Our modeling focused on the mathematical representation of these stored carbon reserves, and we examined the sensitivity of model performance to different model structures. This project contributes to DOE’s goal to improve next-generation models of the earth system, and to understand the impacts of climate change on terrestrial ecosystems.« less
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Gaston, G.G.; Kolchugina, T.P.
1995-12-01
Forty-two regions with similar vegetation and landcover were identified in the former Soviet Union (FSU) by classifying Global Vegetation Index (GVI) images. Image classes were described in terms of vegetation and landcover. Image classes appear to provide more accurate and precise descriptions for most ecosystems when compared to general thematic maps. The area of forest lands were estimated at 1,330 Mha and the actual area of forest ecosystems at 875 Mha. Arable lands were estimated to be 211 Mha. The area of the tundra biome was estimated at 261 Mha. The areas of the forest-tundra/dwarf forest, taiga, mixed-deciduous forest andmore » forest-steppe biomes were estimated t 153, 882, 196, and 144 Mha, respectively. The areas of desert-semidesert biome and arable land with irrigated land and meadows, were estimated at 126 and 237 Mha, respectively. Vegetation and landcover types were associated with the Bazilevich database of phytomass and NPP for vegetation in the FSU. The phytomass in the FSU was estimated at 97.1 Gt C, with 86.8 in forest vegetation, 9.7 in natural non-forest and 0.6 Gt C in arable lands. The NPP was estimated at 8.6 Gt C/yr, with 3.2, 4.8, and 0.6 Gt C/yr of forest, natural non-forest, and arable ecosystems, respectively. The phytomass estimates for forests were greater than previous assessments which considered the age-class distribution of forest stands in the FSU. The NPP of natural ecosystems estimated in this study was 23% greater than previous estimates which used thematic maps to identify ecosystems. 47 refs., 4 figs., 2 tabs.« less
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Towards improved bottom-up inventories of methane from the European land surface
NASA Astrophysics Data System (ADS)
Grunwald, Dennis; Fender, Ann-Catrin; Erasmi, Stefan; Jungkunst, Hermann F.
2012-05-01
Forests and wetlands are generally seen as opposites in the methane cycle of terrestrial ecosystems. Wetlands are sources for atmospheric methane and forest soils sinks. However, this greenhouse gas is also emitted by wet forest soils, which is commonly disregarded due to lacking information on their spatial distribution. Here, we estimated the potential bias made for the European methane budget of terrestrial ecosystems when neglecting wet forest ecosystems but including rice paddies and latest estimates for lakes. We appointed distinct annual methane rates for individual land use types based on a literature survey and weighted them according to their European area. This was performed separately for four major ecozones (cold, temperate, continental and Mediterranean). Three approaches were applied: (1) the mean values for forests and wetlands were calculated in three different scenarios, (2) assuming that boreal needle-leaved evergreen forest with a low tree cover (<40%) is predominately forested wetland (3) assuming different shares of wet forest ecosystems in individual forest areas. For the net balance 2.8 Tg CH4-C a-1 were calculated which includes emissions from rice paddies (0.2 Tg CH4-C a-1) and from lakes (2.5 Tg CH4-C a-1). The different approaches for the net balances that included wet forest ecosystems mainly ranged between 4.6 and 6.7 Tg CH4-C a-1. The results suggest that wet forest ecosystems are approximately as important as wetlands for the European methane balance. European bottom-up inventories are improved best by more accurate mapping of wetlands both within and outside forests and more flux data for lakes and continental wetlands.
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Epiphytic lichens as sentinels for heavy metal pollution at forest ecosystems (central Italy).
Loppi, Stefano; Pirintsos, Stergios Arg
2003-01-01
The results of a study using epiphytic lichens (Parmelia caperata) as sentinels for heavy metal deposition at six selected forest ecosystems of central Italy are reported. The woods investigated are characterized by holm oak (Quercus ilex), turkey oak (Quercus cerris) and beech (Fagus sylvatica) and represent the typical forest ecosystems of central Italy at low, medium and high elevations, respectively. The results showed that levels of heavy metals in lichens were relatively low and consequently no risk of heavy metal air pollution is expected for the six forest ecosystems investigated. However, for two of them there are indications of a potential risk: the beech forest of Vallombrosa showed signs of contamination by Pb as a consequence of vehicle traffic due to the rather high touristic pressure in the area, and the holm oak forest of Cala Violina showed transboundary pollution by Mn, Cr and Ni originating from the steel industry in Piombino. Epiphytic lichens proved to be very effective as an early warning system to detect signs of a changing environment at forest ecosystems.
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Kulakowski, Dominik; Seidl, Rupert; Holeksa, Jan; Kuuluvainen, Timo; Nagel, Thomas A; Panayotov, Momchil; Svoboda, Miroslav; Thorn, Simon; Vacchiano, Giorgio; Whitlock, Cathy; Wohlgemuth, Thomas; Bebi, Peter
2017-03-15
Mountain forests are among the most important ecosystems in Europe as they support numerous ecological, hydrological, climatic, social, and economic functions. They are unique relatively natural ecosystems consisting of long-lived species in an otherwise densely populated human landscape. Despite this, centuries of intensive forest management in many of these forests have eclipsed evidence of natural processes, especially the role of disturbances in long-term forest dynamics. Recent trends of land abandonment and establishment of protected forests have coincided with a growing interest in managing forests in more natural states. At the same time, the importance of past disturbances highlighted in an emerging body of literature, and recent increasing disturbances due to climate change are challenging long-held views of dynamics in these ecosystems. Here, we synthesize aspects of this Special Issue on the ecology of mountain forest ecosystems in Europe in the context of broader discussions in the field, to present a new perspective on these ecosystems and their natural disturbance regimes. Most mountain forests in Europe, for which long-term data are available, show a strong and long-term effect of not only human land use but also of natural disturbances that vary by orders of magnitude in size and frequency. Although these disturbances may kill many trees, the forests themselves have not been threatened. The relative importance of natural disturbances, land use, and climate change for ecosystem dynamics varies across space and time. Across the continent, changing climate and land use are altering forest cover, forest structure, tree demography, and natural disturbances, including fires, insect outbreaks, avalanches, and wind disturbances. Projected continued increases in forest area and biomass along with continued warming are likely to further promote forest disturbances. Episodic disturbances may foster ecosystem adaptation to the effects of ongoing and future climatic change. Increasing disturbances, along with trends of less intense land use, will promote further increases in coarse woody debris, with cascading positive effects on biodiversity, edaphic conditions, biogeochemical cycles, and increased heterogeneity across a range of spatial scales. Together, this may translate to disturbance-mediated resilience of forest landscapes and increased biodiversity, as long as climate and disturbance regimes remain within the tolerance of relevant species. Understanding ecological variability, even imperfectly, is integral to anticipating vulnerabilities and promoting ecological resilience, especially under growing uncertainty. Allowing some forests to be shaped by natural processes may be congruent with multiple goals of forest management, even in densely settled and developed countries.
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Carbon Dynamics in Vegetation and Soils
NASA Technical Reports Server (NTRS)
Trumbore, Susan; Chambers, Jeffrey Q.; Camargo, Plinio; Martinelli, Luiz; Santos, Joaquim
2005-01-01
The overall goals of CD-08 team in Phase I were to quantify the contributions of different components of the carbon cycle to overall ecosystem carbon balance in Amazonian tropical forests and to undertake process studies at a number of sites along the eastern LBA transect to understand how and why these fluxes vary with site, season, and year. We divided this work into a number of specific tasks: (1) determining the average rate (and variability) of tree growth over the past 3 decades; (2) determining age demographics of tree populations, using radiocarbon to determine tree age; (3) assessing the rate of production and decomposition of dead wood debris; (4) determining turnover rates for organic matter in soils and the mean age of C respired from soil using radiocarbon measurements; and (5) comparing our results with models and constructing models to predict the potential of tropical forests to function as sources or sinks of C. This report summarizes the considerable progress made towards our original goals, which have led to increased understanding of the potential for central Amazon forests to act as sources or sinks of carbon with altered productivity. The overall picture of tropical forest C dynamics emerging from our Phase I studies suggests that the fraction of gross primary production allocated to growth in these forests is only 25-30%, as opposed to the 50% assumed by many ecosystem models. Consequent slow tree growth rates mean greater mean tree age for a given diameter, as reflected in our measurements and models of tree age. Radiocarbon measurements in leaf and root litter suggest that carbon stays in living tree biomass for several years up to a decade before being added to soils, where decomposition is rapid. The time lags predicted from 14C, when coupled with climate variation on similar time scales, can lead to significant interannual variation in net ecosystem C exchange.
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Characterization of potential fire regimes: applying landscape ecology to fire management in Mexico
NASA Astrophysics Data System (ADS)
Jardel, E.; Alvarado, E.; Perez-Salicrup, D.; Morfín-Rios, J.
2013-05-01
Knowledge and understanding of fire regimes is fundamental to design sound fire management practices. The high ecosystem diversity of Mexico offers a great challenge to characterize the fire regime variation at the landscape level. A conceptual model was developed considering the main factors controlling fire regimes: climate and vegetation cover. We classified landscape units combining bioclimatic zones from the Holdridge life-zone system and actual vegetation cover. Since bioclimatic conditions control primary productivity and biomass accumulation (potential fuel), each landscape unit was considered as a fuel bed with a particular fire intensity and behavior potential. Climate is also a determinant factor of post-fire recovery rates of fuel beds, and climate seasonality (length of the dry and wet seasons) influences fire probability (available fuel and ignition efficiency). These two factors influence potential fire frequency. Potential fire severity can be inferred from fire frequency, fire intensity and behavior, and vegetation composition and structure. Based in the conceptual model, an exhaustive literature review and expert opinion, we developed rules to assign a potential fire regime (PFR) defined by frequency, intensity and severity (i.e. fire regime) to each bioclimatic-vegetation landscape unit. Three groups and eight types of potential fire regimes were identified. In Group A are fire-prone ecosystems with frequent low severity surface fires in grasslands (PFR type I) or forests with long dry season (II) and infrequent high-severity fires in chaparral (III), wet temperate forests (IV, fire restricted by humidity), and dry temperate forests (V, fire restricted by fuel recovery rate). Group B includes fire-reluctant ecosystems with very infrequent or occasional mixed severity surface fires limited by moisture in tropical rain forests (VI) or fuel availability in seasonally dry tropical forests (VII). Group C and PFR VIII include fire-free environments that correspond to deserts. Application of PFR model to fire management is discussed.
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Loss of foundation species: consequences for the structure and dynamics of forested ecosystems
Aaron M. Ellison; Michael S. Bank; Barton D. Clinton; Elizabeth A. Colburn; Katherine Elliott; Chelcy Rae Ford; David R. Foster; Brian D. Kloeppel; Jennifer D. Knoepp; Gary M. Lovett; Jacqueline Mohan; David A. Orwig; Nicholas L. Rodenhouse; William V. Sobczak; Kristina A. Stinson; Jeffrey K. Stone; Christopher M. Swan; Jill Thompson; Betsy Von Holle; Jackson R. Webster
2005-01-01
In many forested ecosystems, the architecture and functional ecology of certain tree species define forest structure and their species-specific traits control ecosystem dynamics. Such foundation tree species are declining throughout the world due to introductions and outbreaks of pests and pathogens, selective removal of individual taxa, and over-harvesting. Through a...
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Deborah K. Kennard; H. Michael Rauscher; Patricia A. Flebbe; Daniel L. Schmoldt; William G. Hubbard; J. Bryan Jordin; William Milnor
2003-01-01
The Encyclopedia of Southern Appalachian Forest Ecosystems (ESAFE), a hyperdocument-based encyclopedia system available on the Internet, provides an organized synthesis of existing research on the management and ecology of Southern Appalachian forests ecosystems. The encyclopedia is dynamic, so that new or revised content can be submitted directly through the Internet...
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Forest reference conditions for ecosystem management in the Sacramento Mountains, New Mexico
M. R. Kaufmann; L. S. Huckaby; C. M. Regan; J. Popp
1998-01-01
We present the history of land use and historic vegetation conditions on the Sacramento Ranger District of the Lincoln National Forest within the framework of an ecosystem needs assessment. We reconstruct forest vegetation conditions and ecosystem processes for the period immediately before Anglo-American settlement using General Land Office survey records, historic...
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Scaling ozone responses of forest trees to the ecosystem level in a changing climate
D.F. Karnosky; K.S. Pregitzer; D.R. Zak; M.E. Kubiske; G.R. Hendrey; D. Weinstein; M. Nosal; K.E. Percy
2005-01-01
Many uncertainties remain regarding how climate change will alter the structure and function of forest ecosystems. At the Aspen FACE experiment in northern Wisconsin, we are attempting to understand how an aspen/birch/maple forest ecosystem responds to long-term exposure to elevated carbon dioxide (CO2) and ozone (O3),...
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Climate change, forests, fire, water, and fish: Building resilient landscapes, streams, and managers
Charles Luce; Penny Morgan; Kathleen Dwire; Daniel Isaak; Zachary Holden; Bruce Rieman
2012-01-01
Fire will play an important role in shaping forest and stream ecosystems as the climate changes. Historic observations show increased dryness accompanying more widespread fire and forest die-off. These events punctuate gradual changes to ecosystems and sometimes generate stepwise changes in ecosystems. Climate vulnerability assessments need to account for fire in their...
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Spatial complementarity of forests and farms: accounting for ecosystem services
Subhrendu K. Pattanayak; David T. Butry
2006-01-01
Our article considers the economic contributions of forest ecosystem services, using a case study from Flores, Indonesia, in which forest protection in upstream watersheds stabilize soil and hydrological flows in downstream farms. We focus on the demand for a weak complement to the ecosystem services--farm labor-- and account for spatial dependence due to economic...
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Fei, Xuehai; Song, Qinghai; Zhang, Yiping; Liu, Yuntong; Sha, Liqing; Yu, Guirui; Zhang, Leiming; Duan, Changqun; Deng, Yun; Wu, Chuansheng; Lu, Zhiyun; Luo, Kang; Chen, Aiguo; Xu, Kun; Liu, Weiwei; Huang, Hua; Jin, Yanqiang; Zhou, Ruiwu; Li, Jing; Lin, Youxing; Zhou, Liguo; Fu, Yane; Bai, Xiaolong; Tang, Xianhui; Gao, Jinbo; Zhou, Wenjun; Grace, John
2018-03-01
Forest ecosystems play an increasingly important role in the global carbon cycle. However, knowledge on carbon exchanges, their spatio-temporal patterns, and the extent of the key controls that affect carbon fluxes is lacking. In this study, we employed 29-site-years of eddy covariance data to observe the state, spatio-temporal variations and climate sensitivity of carbon fluxes (gross primary productivity (GPP), ecosystem respiration (R eco ), and net ecosystem carbon exchange (NEE)) in four representative forest ecosystems in Yunnan. We found that 1) all four forest ecosystems were carbon sinks (the average NEE was -3.40tCha -1 yr -1 ); 2) contrasting seasonality of the NEE among the ecosystems with a carbon sink mainly during the wet season in the Yuanjiang savanna ecosystem (YJ) but during the dry season in the Xishuangbanna tropical rainforest ecosystem (XSBN), besides an equivalent NEE uptake was observed during the wet/dry season in the Ailaoshan subtropical evergreen broad-leaved forest ecosystem (ALS) and Lijiang subalpine coniferous forest ecosystem (LJ); 3) as the GPP increased, the net ecosystem production (NEP) first increased and then decreased when the GPP>17.5tCha -1 yr -1 ; 4) the precipitation determines the carbon sinks in the savanna ecosystem (e.g., YJ), while temperature did so in the tropical forest ecosystem (e.g., XSBN); 5) overall, under the circumstances of warming and decreased precipitation, the carbon sink might decrease in the YJ but maybe increase in the ALS and LJ, while future strength of the sink in the XSBN is somewhat uncertain. However, based on the redundancy analysis, the temperature and precipitation combined together explained 39.7%, 32.2%, 25.3%, and 29.6% of the variations in the NEE in the YJ, XSBN, ALS and LJ, respectively, which indicates that considerable changes in the NEE could not be explained by variations in the temperature and precipitation. Therefore, the effects of other factors (e.g., CO 2 concentration, N/P deposition, aerosol and other variables) on the NEE still require extensive research and need to be considered seriously in carbon-cycle-models. Copyright © 2017. Published by Elsevier B.V.
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Russell, Matthew B.; D'Amato, Anthony W.; Schulz, Bethany K.; Woodall, Christopher W.; Domke, Grant M.; Bradford, John B.
2014-01-01
The contribution of understorey vegetation (UVEG) to forest ecosystem biomass and carbon (C) across diverse forest types has, to date, eluded quantification at regional and national scales. Efforts to quantify UVEG C have been limited to field-intensive studies or broad-scale modelling approaches lacking field measurements. Although large-scale inventories of UVEG C are not common, species- and community-level inventories of vegetation structure are available and may prove useful in quantifying UVEG C stocks. This analysis developed a general framework for estimating UVEG C stocks by employing per cent cover estimates of UVEG from a region-wide forest inventory coupled with an estimate of maximum UVEG C across the US Lake States (i.e. Michigan, Minnesota and Wisconsin). Estimates of UVEG C stocks from this approach reasonably align with expected C stocks in the study region, ranging from 0.86 ± 0.06 Mg ha-1 in red pine-dominated to 1.59 ± 0.06 Mg ha-1 for aspen/birch-dominated forest types. Although the data employed here were originally collected to assess broad-scale forest structure and diversity, this study proposes a framework for using UVEG inventories as a foundation for estimating C stocks in an often overlooked, yet important ecosystem C pool.
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Liu, Zhihua
2016-11-18
Understanding the influence of climate variability and fire characteristics in shaping postfire vegetation recovery will help to predict future ecosystem trajectories in boreal forests. In this study, I asked: (1) which remotely-sensed vegetation index (VI) is a good proxy for vegetation recovery? and (2) what are the relative influences of climate and fire in controlling postfire vegetation recovery in a Siberian larch forest, a globally important but poorly understood ecosystem type? Analysis showed that the shortwave infrared (SWIR) VI is a good indicator of postfire vegetation recovery in boreal larch forests. A boosted regression tree analysis showed that postfire recovery was collectively controlled by processes that controlled seed availability, as well as by site conditions and climate variability. Fire severity and its spatial variability played a dominant role in determining vegetation recovery, indicating seed availability as the primary mechanism affecting postfire forest resilience. Environmental and immediate postfire climatic conditions appear to be less important, but interact strongly with fire severity to influence postfire recovery. If future warming and fire regimes manifest as expected in this region, seed limitation and climate-induced regeneration failure will become more prevalent and severe, which may cause forests to shift to alternative stable states.
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Liu, Zhihua
2016-01-01
Understanding the influence of climate variability and fire characteristics in shaping postfire vegetation recovery will help to predict future ecosystem trajectories in boreal forests. In this study, I asked: (1) which remotely-sensed vegetation index (VI) is a good proxy for vegetation recovery? and (2) what are the relative influences of climate and fire in controlling postfire vegetation recovery in a Siberian larch forest, a globally important but poorly understood ecosystem type? Analysis showed that the shortwave infrared (SWIR) VI is a good indicator of postfire vegetation recovery in boreal larch forests. A boosted regression tree analysis showed that postfire recovery was collectively controlled by processes that controlled seed availability, as well as by site conditions and climate variability. Fire severity and its spatial variability played a dominant role in determining vegetation recovery, indicating seed availability as the primary mechanism affecting postfire forest resilience. Environmental and immediate postfire climatic conditions appear to be less important, but interact strongly with fire severity to influence postfire recovery. If future warming and fire regimes manifest as expected in this region, seed limitation and climate-induced regeneration failure will become more prevalent and severe, which may cause forests to shift to alternative stable states. PMID:27857204
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NASA Astrophysics Data System (ADS)
Zegrar, A.
2008-05-01
The Algerian forests present an important ecological diversity, due to the different type of weather, from the sub humid to arid. These type of weather have a direct influence on the forests ecosystem and condition the flours composition of these forests as well as their regeneration. The ecological diversity of some forests as part as it's constitution, plays an important role in the natural regeneration, following some natural curses (Forest fire, phenomenon of Chablis, stroke of wood...). The conservation of the biologic diversity and the bets in permanent value of some Forests ecosystem take moreover importance. Because the forest ecosystem have the aspect of uniting the biologic wealth of forests, some interior waters, some agricultural earths and some arid and sub humid earths. In this survey, the utilization of remote sensing data respectively satellite ALSAT-1 and satellite LANDSAT TM in different dates, inform us about impact of arid weather on the ecological diversity in the middle of some vegetal steppe formations and in particular on the regressive evolution of some forests ecosystem under the name of the DEFORESTATION. We have used data of satellite LANDSAT TM of the year 1989 and those of satellite ALSAT-1 of the year 2007, for a multistage study of the regressive evolution of forests ecosystem. an application of the specific treatments especially the classification supervised by the method of maximum of verisimilitude is used in order to identify the most important formations of the zone of survey. The index: NDVI, MSAVI2 and the index of IV verdure is used for characterized and determined the forests formations changes. The arithmetic combinations are used in the system of information geographical IDRISI. And after application of the method of the rations we obtained a picture of the changes. A map of the Vulnerability of the forests ecosystem was realized, this map informs us on the process of deforestation in the natural forests following the different aggression and permit us a possible perspectives of harnessing.
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NASA Astrophysics Data System (ADS)
Zhang, Junjun; Peng, Changhui; Zhu, Qiuan; Xue, Wei; Shen, Yan; Yang, Yanzheng; Shi, Guohua; Shi, Shengwei; Wang, Meng
2016-10-01
An incubation experiment was conducted at three temperature levels (8, 18 and 28 °C) to quantify the response of soil CO2 and N2O emissions to temperature in three ecosystems (pine forest, oak forest, and meadow) located in the Qinling Mountains of China, which are considered to be susceptible to disturbance and climate changes, especially global warming. The soil CO2 emission rates increased with temperature and decreased with soil depth; they were the highest in the oak forest (broadleaf forest) and were lower in the pine forest (coniferous forest) and the meadow ecosystem. However, there was no significant difference in the soil N2O emission rates among the three ecosystems. The temperature sensitivity of CO2 and N2O was higher in the forest than in the meadow ecosystem. The Q10 values (temperature sensitivity coefficient) for CO2 and N2O were 1.07-2.25 and 0.82-1.22, respectively, for the three ecosystems. There was also evidence that the CO2 and N2O emission rates were positively correlated. The soil characteristics exhibited different effects on CO2 and N2O emissions among different ecosystems at the three temperature levels. Moreover, the soil dissolved organic carbon (DOC), specific ultraviolet absorbance (SUVA) and nitrate (NO3-) were important factors for CO2 emissions, whereas the soil ammonium (NH4+) and pH were the major controllers of N2O emissions. Unexpectedly, our results indicated that CO2 emissions are more sensitive to increasing temperature than N2O, noting the different feedback of CO2 and N2O emissions to global warming in this region. The different responses of greenhouse gas emissions in different forest types and a meadow ecosystem suggest that it is critical to conduct a comprehensive investigation of the complex mountain forest and meadow ecosystem in the transitional climate zone under global warming. Our research results provide new insight and advanced understanding of the variations in major greenhouse gas emissions (CO2 and N2O) and soil characteristics in response to warming.
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[Contribution of tropical upland forests to carbon storage in Colombia].
Yepes, Adriana; Herrera, Johana; Phillips, Juan; Galindo, Gustavo; Granados, Edwin; Duque, Alvaro; Barbosa, Adriana; Olarte, Claudia; Cardona, María
2015-03-01
The tropical montane forests in the Colombian Andean region are located above 1500 m, and have been heavily deforested. Despite the general presumption that productivity and hence carbon stocks in these ecosystems are low, studies in this regard are scarce. This study aimed to (i) to estimate Above Ground Biomass (AGB) in forests located in the South of the Colombian Andean region, (ii) to identify the carbon storage potential of tropical montane forests dominated by the black oak Colombobalanus excelsa and to identify the relationship between AGB and altitude, and (iii) to analyze the role of tropical mountain forests in conservation mechanisms such as Payment for Environmental Services (PES) and Reducing Emissions from Deforestation and Degradation (REDD+). Twenty six 0.25 ha plots were randomly distributed in the forests and all trees with D > or =10 cm were measured. The results provided important elements for understanding the role of tropical montane forests as carbon sinks. The information produced can be used in subnational initiatives, which seek to mitigate or reduce the effects of deforestation through management or conservation of these ecosystems, like REDD+ or PES. The AGB and carbon stocks results obtained were similar to those reported for lowland tropical forests. These could be explained by the dominance and abundance of C. excelsa, which accounted for over 81% of AGB/carbon. The error associated with the estimates of AGB/carbon was 10.58%. We found a negative and significant relationship between AGB and altitude, but the higher AGB values were in middle altitudes (approximatly = 700-1800 m), where the environmental conditions could be favorable to their growth. The carbon storage potential of these forests was higher. However, if the historical rate of the deforestation in the study area continues, the gross emissions of CO2e to the atmosphere could turn these forests in to an important emissions source. Nowadays, it is clear that tropical montane forests are vulnerable to deforestation, especially black Oak forests due to their commercial value. Given their high carbon storage potential, the presence of endemic species and the strategic functions of these ecosystems, we recommend that they should be considered relevant during REDD+, PES or any other conservation assessment.
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NASA Astrophysics Data System (ADS)
Bell, D. M.; Gray, A. N.
2014-12-01
Forest successional theory describes the changes in forest biomass and community composition from forest establishment to climax communities, but the drivers of succession are still widely debated. For example, successional models have related biomass and community change to stand age, species rarity within the community, small-scale disturbance, or the ability of species to survive under low resource conditions. The degree to which these drivers might vary regionally limits our ability to model and predict ecosystem change. Our objective was to assess whether forest successional theory explains observed changes in species biomass and community composition across forests of the U. S. Pacific Northwest. Using remeasurements of 9,700 Current Vegetation Survey (CVS) National Forest inventory plots primarily in Oregon and Washington, we quantified the effects of forest stand age, community composition, disturbance, and moisture (i.e., topography and climate) on changes in species-specific proportional live biomass (ΔB) and species dominance (ΔD). We focused on differences in forest successional patterns in two vegetation zones: the Tsuga heterophylla (TSHE) zone, found at low elevations on the wet, west side of the Cascade Mountains; and the Abies concolor (ABCO) zone, found at mid-elevations on the dry, east side of the Cascade Mountains. Preliminary results indicate that the regional differences in tree species biomass change and dominance appear to be related to responses to climate and disturbance. Strong positive effects of cover change on ΔB were observed in the drier ABCO zone, but not the wetter TSHE zone. ΔB and ΔD were more often sensitive to precipitation and topographic position in the ABCO zone. In both regions, we found that ΔB was strongly negatively related to species biomass and stand age while ΔD was strongly negatively related to relative density, highlighting the importance of both age and community in shaping succession. Given that the importance of different forest successional processes in shaping ecosystem change varied regionally, this work provides valuable insights into potential risks of changing climate and disturbance regimes to species persistence and ecosystem stability across forests of the U.S. Pacific Northwest.
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NASA Astrophysics Data System (ADS)
Jackson, C. R.; Webster, J. R.; Knoepp, J. D.; Elliott, K.; Emanuel, R. E.; Miniat, C.
2017-12-01
In the 1970s, the Coweeta Hydrologic Laboratory Watershed 7 was clearcut from ridge to ridge to observe how far the perturbation would move the ecosystem and how quickly the ecosystem would return to its pre-disturbance state. Nearly 40 years of observations of streamflow and DIN export demonstrate that this view of ecosystem resistance and resilience was too simplistic. Forest disturbance triggered a chain of ecological dynamics that are still evolving. For the first 12 years following watershed road building, forest harvest, and forest regeneration, streamflows and DIN concentrations temporarily increased and then appeared to return to pre-harvest behavior. Thereupon the ecosystem trajectory diverged from expectations. Unexpected successional changes in forest composition interacted with drought cycles, climate change effects, and forest changes due to pests and diseases to push the biogeochemical system into an alternate state featuring persistently high DIN concentrations and hydrological rather than biological control of DIN exports. Thirty years after harvest, these forest changes also increased evapotranspiration and reduced water yields. These ecosystem dynamics were only revealed because of long-term monitoring, and they inspired new research to elucidate mechanisms behind these dynamics. We conclude that long-term approaches are critical for understanding ecosystem dynamics and responses to disturbances.
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Coupling fine-scale root and canopy structure using ground-based remote sensing
Hardiman, Brady S.; Gough, Christopher M.; Butnor, John R.; ...
2017-02-21
Ecosystem physical structure, defined by the quantity and spatial distribution of biomass, influences a range of ecosystem functions. Remote sensing tools permit the non-destructive characterization of canopy and root features, potentially providing opportunities to link above- and belowground structure at fine spatial resolution in functionally meaningful ways. To test this possibility, we employed ground-based portable canopy LiDAR (PCL) and ground penetrating radar (GPR) along co-located transects in forested sites spanning multiple stages of ecosystem development and, consequently, of structural complexity. We examined canopy and root structural data for coherence (i.e., correlation in the frequency of spatial variation) at multiple spatialmore » scales 10 m within each site using wavelet analysis. Forest sites varied substantially in vertical canopy and root structure, with leaf area index and root mass more becoming even vertically as forests aged. In all sites, above- and belowground structure, characterized as mean maximum canopy height and root mass, exhibited significant coherence at a scale of 3.5–4 m, and results suggest that the scale of coherence may increase with stand age. Our findings demonstrate that canopy and root structure are linked at characteristic spatial scales, which provides the basis to optimize scales of observation. Lastly, our study highlights the potential, and limitations, for fusing LiDAR and radar technologies to quantitatively couple above- and belowground ecosystem structure.« less
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Coupling fine-scale root and canopy structure using ground-based remote sensing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hardiman, Brady S.; Gough, Christopher M.; Butnor, John R.
Ecosystem physical structure, defined by the quantity and spatial distribution of biomass, influences a range of ecosystem functions. Remote sensing tools permit the non-destructive characterization of canopy and root features, potentially providing opportunities to link above- and belowground structure at fine spatial resolution in functionally meaningful ways. To test this possibility, we employed ground-based portable canopy LiDAR (PCL) and ground penetrating radar (GPR) along co-located transects in forested sites spanning multiple stages of ecosystem development and, consequently, of structural complexity. We examined canopy and root structural data for coherence (i.e., correlation in the frequency of spatial variation) at multiple spatialmore » scales 10 m within each site using wavelet analysis. Forest sites varied substantially in vertical canopy and root structure, with leaf area index and root mass more becoming even vertically as forests aged. In all sites, above- and belowground structure, characterized as mean maximum canopy height and root mass, exhibited significant coherence at a scale of 3.5–4 m, and results suggest that the scale of coherence may increase with stand age. Our findings demonstrate that canopy and root structure are linked at characteristic spatial scales, which provides the basis to optimize scales of observation. Lastly, our study highlights the potential, and limitations, for fusing LiDAR and radar technologies to quantitatively couple above- and belowground ecosystem structure.« less
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Hubbart, Jason A; Guyette, Richard; Muzika, Rose-Marie
2016-10-01
For many regions of the Earth, anthropogenic climate change is expected to result in increasingly divergent climate extremes. However, little is known about how increasing climate variance may affect ecosystem productivity. Forest ecosystems may be particularly susceptible to this problem considering the complex organizational structure of specialized species niche adaptations. Forest decline is often attributable to multiple stressors including prolonged heat, wildfire and insect outbreaks. These disturbances, often categorized as megadisturbances, can push temperate forests beyond sustainability thresholds. Absent from much of the contemporary forest health literature, however, is the discussion of excessive precipitation that may affect other disturbances synergistically or that might represent a principal stressor. Here, specific points of evidence are provided including historic climatology, variance predictions from global change modeling, Midwestern paleo climate data, local climate influences on net ecosystem exchange and productivity, and pathogen influences on oak mortality. Data sources reveal potential trends, deserving further investigation, indicating that the western edge of the Eastern Deciduous forest may be impacted by ongoing increased precipitation, precipitation variance and excessive wetness. Data presented, in conjunction with recent regional forest health concerns, suggest that climate variance including drought and excessive wetness should be equally considered for forest ecosystem resilience against increasingly dynamic climate. This communication serves as an alert to the need for studies on potential impacts of increasing climate variance and excessive wetness in forest ecosystem health and productivity in the Midwest US and similar forest ecosystems globally. Copyright © 2016 Elsevier B.V. All rights reserved.
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Xu, Zhi-Wei; Zhang, Xin-Yu; Sun, Xiao-Min; Yuan, Guo-Fu; Wang, Sheng-Zhong; Liu, Wen-Hua
2011-10-01
The nitrate-N (NO3(-) -N) concentrations of 38 shallow groundwater wells from 31 of the typical terrestrial ecosystems on Chinese Ecosystem Research Network (CERN) were assessed using the monitoring data from 2004 to 2009. The results showed that the average values of NO3(-) -N concentrations were significantly higher in the agricultural (4.85 mg x L(-1) +/- 0.42 mg x L(-1)), desert (oasis) (3.72 mg x L(-1) +/- 0.42 mg x L(-1)) and urban ecosystems (3.77 mg x L(-1) 0.51 mg x L(-1)) than in the grass (1.59 mg x L(-1) +/- 0.35 mg L(-1)) and forest ecosystems (0.39 mg x L(-1) +/- 0.03 mg x L(-1)). Nitrate was the major form of nitrogen, with between 56% to 88% of nitrogen in the nitrate-N form in the shallow groundwater of desert (oasis), urban and agricultural ecosystems. Nitrate-N concentrations for some agricultural ecosystems (Ansai, Yanting, Yucheng) and desert (oasis) ecosystems (Cele, Linze, Akesu) analysis exceeded the 10 mg x L(-1) World Health Organization drinking water standards between 14.3% and 84.6%. Significant seasonality was found in Ansai, Fengqiu, Yanting agricultural ecosystems and the Beijing urban ecosystem using the relatively high frequency monitoring data, with the higher nitrate concentrations usually found during summer and winter months. The monitoring results indicated that the shallow groundwater of agricultural ecosystems was contaminated by agricultural management practices, i.e. fertilization, while the shallow groundwater of forest ecosystems was under natural condition with no contamination from human activities.
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Ion fluxes from fog and rain to an agricultural and a forest ecosystem in Europe
NASA Astrophysics Data System (ADS)
Thalmann, E.; Burkard, R.; Wrzesinsky, T.; Eugster, W.; Klemm, O.
The deposition fluxes of inorganic compounds dissolved in fog and rain were quantified for two different ecosystems in Europe. The fogwater deposition fluxes were measured by employing the eddy covariance method. The site in Switzerland that lies within an agricultural area surrounded by the Jura mountains and the Alps is often exposed to radiation fog. At the German mountain forest ecosystem, on the other hand, advection fog occurs most frequently. At the Swiss site, fogwater deposition fluxes of the dominant components SO 42- (0.027 mg S m -2 day -1), NO 3- (0.030 mg N m -2 day -1) and NH 4+ (0.060 mg N m -2 day -1) were estimated to be <5% of the measured wet deposition (0.85, 0.70 and 1.34 mg m -2 day -1, respectively). The corresponding fluxes at the forest site (0.62, 0.82 and 1.16 mg m -2 day -1, respectively) were of the same order of magnitude as wet deposition (1.04, 1.01 and 1.36 mg m -2 day -1), illustrating the importance of fog (or occult) deposition. Trajectory analyses at the forest site indicate significantly higher fogwater concentrations of all major ions if air originated from the east (i.e. the Czech Republic), which is in close agreement with earlier studies.
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Patrick A. Zollner; L. Jay Roberts; Eric J. Gustafson; Hong S. He; Volker Radeloff
2008-01-01
Incorporating an ecosystem management perspective into forest planning requires consideration of the impacts of timber management on a suite of landscape characteristics at broad spatial and long temporal scales. We used the LANDIS forest landscape simulation model to predict forest composition and landscape pattern under seven alternative forest management plans...
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Brian Brookshire; Carl Hauser
1993-01-01
The effects of forest management on non-timber resources are of growing concern to forest managers and the public. While many previous studies have reported effects of stand-level treatments (less than 15 ha) on various stand-level attributes, few studies have attempted to document the influence of forest management on the biotic and abiotic characteristics of entire...
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James E. Smith; Linda S. Heath; Kenneth E. Skog; Richard A. Birdsey
2006-01-01
This study presents techniques for calculating average net annual additions to carbon in forests and in forest products. Forest ecosystem carbon yield tables, representing stand-level merchantable volume and carbon pools as a function of stand age, were developed for 51 forest types within 10 regions of the United States. Separate tables were developed for...
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Rapid colonization of a Hawaiian restoration forest by a diverse avian community
Paxton, Eben H.; Yelenik, Stephanie G.; Borneman, Tracy E.; Rose, Eli; Camp, Richard J.; Kendall, Steve J.
2018-01-01
Deforestation of tropical forests has led to widespread loss and extirpation of forest bird species around the world, including the Hawaiian Islands which have experienced a dramatic loss of forests over the last 200–800 years. Given the important role birds play in forest ecosystem functions via seed dispersal and pollination, a bird community's response to forest restoration is an important measure of the success of such conservation actions. We evaluated the bird response to reforestation at an important bird sanctuary, Hakalau Forest National Wildlife Refuge, Hawai′i Island, using 26 years of bird count data. We show that most species from within the diverse avian community increased significantly, but species colonized the restoration forest at different rates. Distance from intact forest and time since restoration were both important predictors of colonization rate, interacting such that for most species it took more time to colonize areas farther from the intact forest. In addition, both forest cover and understory diversity helped to explain bird densities, but the effect varied among species, suggesting that different habitat requirements may help drive variation in colonization rates. This article provides the first detailed evaluation of how a diverse community of birds has responded to one of the largest, ongoing reforestation projects in Hawai′i.
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Temporal-Spatial Pattern of Carbon Stocks in Forest Ecosystems in Shaanxi, Northwest China
Cui, Gaoyang; Chen, Yunming; Cao, Yang
2015-01-01
The precise and accurate quantitative evaluation of the temporal and spatial pattern of carbon (C) storage in forest ecosystems is critical for understanding the role of forests in the global terrestrial C cycle and is essential for formulating forest management policies to combat climate change. In this study, we examined the C dynamics of forest ecosystems in Shaanxi, northwest China, based on four forest inventories (1989–1993, 1994–1998, 1999–2003, and 2004–2008) and field-sampling measurements (2012). The results indicate that the total C storage of forest ecosystems in Shaanxi increased by approximately 29.3%, from 611.72 Tg in 1993 to 790.75 Tg in 2008, partially as a result of ecological restoration projects. The spatial pattern of C storage in forest ecosystems mainly exhibited a latitude-zonal distribution across the province, increasing from north (high latitude) to south (low latitude) generally, which signifies the effect of environmental conditions, chiefly water and heat related factors, on forest growth and C sequestration. In addition, different data sources and estimation methods had a significant effect on the results obtained, with the C stocks in 2008 being considerably overestimated (864.55 Tg) and slightly underestimated (778.07 Tg) when measured using the mean C density method and integrated method, respectively. Overall, our results demonstrated that the forest ecosystem in Shaanxi acted as a C sink over the last few decades. However, further studies should be carried out with a focus on adaption of plants to environmental factors along with forest management for vegetation restoration to maximize the C sequestration potential and to better cope with climate change. PMID:26353011
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Increased topsoil carbon stock across China's forests.
Yang, Yuanhe; Li, Pin; Ding, Jinzhi; Zhao, Xia; Ma, Wenhong; Ji, Chengjun; Fang, Jingyun
2014-08-01
Biomass carbon accumulation in forest ecosystems is a widespread phenomenon at both regional and global scales. However, as coupled carbon-climate models predicted, a positive feedback could be triggered if accelerated soil carbon decomposition offsets enhanced vegetation growth under a warming climate. It is thus crucial to reveal whether and how soil carbon stock in forest ecosystems has changed over recent decades. However, large-scale changes in soil carbon stock across forest ecosystems have not yet been carefully examined at both regional and global scales, which have been widely perceived as a big bottleneck in untangling carbon-climate feedback. Using newly developed database and sophisticated data mining approach, here we evaluated temporal changes in topsoil carbon stock across major forest ecosystem in China and analysed potential drivers in soil carbon dynamics over broad geographical scale. Our results indicated that topsoil carbon stock increased significantly within all of five major forest types during the period of 1980s-2000s, with an overall rate of 20.0 g C m(-2) yr(-1) (95% confidence interval, 14.1-25.5). The magnitude of soil carbon accumulation across coniferous forests and coniferous/broadleaved mixed forests exhibited meaningful increases with both mean annual temperature and precipitation. Moreover, soil carbon dynamics across these forest ecosystems were positively associated with clay content, with a larger amount of SOC accumulation occurring in fine-textured soils. In contrast, changes in soil carbon stock across broadleaved forests were insensitive to either climatic or edaphic variables. Overall, these results suggest that soil carbon accumulation does not counteract vegetation carbon sequestration across China's forest ecosystems. The combination of soil carbon accumulation and vegetation carbon sequestration triggers a negative feedback to climate warming, rather than a positive feedback predicted by coupled carbon-climate models. © 2014 John Wiley & Sons Ltd.
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Increasing human dominance of tropical forests.
Lewis, Simon L; Edwards, David P; Galbraith, David
2015-08-21
Tropical forests house over half of Earth's biodiversity and are an important influence on the climate system. These forests are experiencing escalating human influence, altering their health and the provision of important ecosystem functions and services. Impacts started with hunting and millennia-old megafaunal extinctions (phase I), continuing via low-intensity shifting cultivation (phase II), to today's global integration, dominated by intensive permanent agriculture, industrial logging, and attendant fires and fragmentation (phase III). Such ongoing pressures, together with an intensification of global environmental change, may severely degrade forests in the future (phase IV, global simplification) unless new "development without destruction" pathways are established alongside climate change-resilient landscape designs. Copyright © 2015, American Association for the Advancement of Science.
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Theresa B. Jain
1994-01-01
Fluctuations in atmospheric carbon dioxide is influenced by carbon storage and cycling in terrestrial forest ecosystems. Currently, only gross estimates are available for carbon content of these ecosystems and reliable estimates are lacking for Rocky Mountain forests. To improve carbon storage estimates more information is needed on the relationship between carbon and...
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Beetles among us: Social and economic impacts of the MPB epidemic [Chapter 6
Krista Gebert; Greg Jones; Patty Champ; Mike Czaja; Chuck Oliver; Paul E. Cruz; Jessica Clement
2014-01-01
Healthy forest ecosystems provide many goods and services that are vital to human well-being. When forest ecosystems are impacted by disturbances, such as the widespread mountain pine beetle (MPB) epidemic, the services provided by these ecosystems are also affected. Likewise, management in response to large-scale forest disturbances impacts both the natural and human...
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Kirk D. Sinclair; Barbara A. Knuth
2001-01-01
Private forest landowners support the stewardship objectives that can be achieved through ecosystems-based management. However, ecosystems-based management is a data intensive approach that focuses upon the broad forest landscape. Intervention by forestry agents or agencies could help neighboring landowners to collaborate with an ecosystems-based approach in pursuit of...
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Linking an ecosystem model and a landscape model to study forest species response to climate warming
Hong S. He; David J. Mladenoff; Thomas R. Crow
1999-01-01
No single model can address forest change from single tree to regional scales. We discuss a framework linking an ecosystem process model {LINKAGES) with a spatial landscape model (LANDIS) to examine forest species responses to climate warming for a large, heterogeneous landscape in northern Wisconsin, USA. Individual species response at the ecosystem scale was...
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Calcium inputs and transport in a base-poor forest ecosystem as interpreted by Sr isotopes
Scott W. Bailey; James W. Hornbeck; Charles T. Driscoll; Henri E. Gaudette
1996-01-01
Depletion of Ca in forests and its effects on forest health are poorly quantified. Depletion has been difficult to document due to limitations in determining rates at which Ca becomes available for ecosystem processes through weathering, and difficulty in determining changes in ecosystem storage. We coupled a detailed analysis of Sr isotopic composition with a mass...
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Edward Gage; David J. Cooper
2013-01-01
This document provides an overview of historical range of variation concepts and explores their application to wetland and riparian ecosystems in the US Forest Service Rocky Mountain Region (Region 2), which includes National Forests and National Grasslands occurring in the states of Colorado, Wyoming, Nebraska, Kansas, and South Dakota. For each of five ecosystem...
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Dynamic and inertial controls on forest carbon-water relations
NASA Astrophysics Data System (ADS)
Maxwell, T.; Silva, L.; Horwath, W. R.
2017-12-01
This study fuses theory, empirical measurements, and statistical models to evaluate multiple processes controlling coupled carbon-water cycles in forest ecosystems. A series of latitudinal and altitudinal transects across the California Sierra Nevada was used to study the effects of climatic and edaphic gradients on intrinsic water-use efficiency (iWUE) - CO2 fixed per unit of water lost via transpiration - of nine dominant trees species. Transfer functions were determined between leaf, litter, and soil organic matter stable isotope ratios of carbon, oxygen, and nitrogen, revealing causal links between the physiological performance of tree species and stand-level estimations of productivity and water balance. Our results show that species iWUE is governed both by leaf traits (24% of the variation) and edaphic properties, such as parent material and soil development (3% and 12% of the variation, respectively). We show that soil properties combined with isotopic indicators can be used to explain constraints over iWUE by regulating water and nutrient availability across elevation gradients. Based on observed compositional shifts likely driven by changing climates in the region, encroachment of broad leaf trees could lead to an 80% increase in water loss via transpiration for each unit of CO2 fixed in Sierra mixed conifer zones. A combination of field-based, laboratory, and remote sensed data provide a useful framework for differentiating the effect of multiple controls of carbon and water cycles in temperate forest ecosystems.
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Chen, Guangsheng; Tian, Hanqin; Huang, Chengquan; ...
2013-07-01
Forest ecosystems in the southern United States are dramatically altered by three major disturbances: timber harvesting, hurricane, and permanent land conversion. Understanding and quantifying effects of disturbance on forest carbon, nitrogen, and water cycles is critical for sustainable forest management in this region. In this study, we introduced a process-based ecosystem model for simulating forest disturbance impacts on ecosystem carbon, nitrogen, and water cycles. Based on forest mortality data classified from Landsat TM/ETM + images, this model was then applied to estimate changes in carbon storage using Mississippi and Alabama as a case study. Mean annual forest mortality rate formore » these states was 2.37%. Due to frequent disturbance, over 50% of the forest land in the study region was less than 30 years old. Forest disturbance events caused a large carbon source (138.92 Tg C, 6.04 Tg C yr -1; 1 Tg = 10 12 g) for both states during 1984–2007, accounting for 2.89% (4.81% if disregard carbon storage changes in wood products) of the total forest carbon storage in this region. Large decreases and slow recovery of forest biomass were the main causes for carbon release. Forest disturbance could result in a carbon sink in few areas if wood product carbon was considered as a local carbon pool, indicating the importance of accounting for wood product carbon when assessing forest disturbance effects. The legacy effects of forest disturbance on ecosystem carbon storage could last over 50 years. Lastly, this study implies that understanding forest disturbance impacts on carbon dynamics is of critical importance for assessing regional carbon budgets.« less
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Liu, Wei-wei; Wang, Xiao-ke; Lu, Fei; Ouyang, Zhi-yun
2015-09-01
As a dominant part of terrestrial ecosystems, forest ecosystem plays an important role in absorbing atmospheric CO2 and global climate change mitigation. From the aspects of zonal climate and geographical distribution, the present carbon stocks and carbon sequestration capacity of forest ecosystem were comprehensively examined based on the review of the latest literatures. The influences of land use change on forest carbon sequestration were analyzed, and factors that leading to the uncertainty of carbon sequestration assessment in forest ecosystem were also discussed. It was estimated that the current forest carbon stock was in the range of 652 to 927 Pg C and the carbon sequestration capacity was approximately 4.02 Pg C · a(-1). In terms of zonal climate, the carbon stock and carbon sequestration capacity of tropical forest were the maximum, about 471 Pg C and 1.02-1.3 Pg C · a(-1) respectively; then the carbon stock of boreal forest was about 272 Pg C, while its carbon sequestration capacity was the minimum, approximately 0.5 Pg C · a(-1); for temperate forest, the carbon stock was minimal, around 113 to 159 Pg C and its carbon sequestration capacity was 0.8 Pg C · a(-1). From the aspect of geographical distribution, the carbon stock of forest ecosystem in South America was the largest (187.7-290 Pg C), then followed by European (162.6 Pg C), North America (106.7 Pg C), Africa (98.2 Pg C) and Asia (74.5 Pg C), and Oceania (21.7 Pg C). In addition, carbon sequestration capacity of regional forest ecosystem was summed up as listed below: Tropical South America forest was the maximum (1276 Tg C · a(-1)), then were Tropical Africa (753 Tg C · a(-1)), North America (248 Tg C · a(-1)) and European (239 Tg C · a(-1)), and East Asia (98.8-136.5 Tg C · a(-1)) was minimum. To further reduce the uncertainty in the estimations of the carbon stock and carbon sequestration capacity of forest ecosystem, comprehensive application of long-term observation, inventories, remote sensing and modeling method should be required.
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Southern Forest Resource Assessment - Technical Report
David N. Wear; John G. Greis
2002-01-01
The southern forest resource assessment provides a comprehensive analysis of the history, status, and likely future of forests in the Southern United States. Twenty-three chapters address questions regarding social/economic systems, terrestrial ecosystems, water and aquatic ecosystems, forest health, and timber management; 2 additional chapters provide a background on...
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Forest operations for ecosystem management
Robert B. Rummer; John Baumgras; Joe McNeel
1997-01-01
The evolution of modern forest resource management is focusing on ecologically sensitive forest operations. This shift in management strategies is producing a new set of functional requirements for forest operations. Systems to implement ecosystem management prescriptions may need to be economically viable over a wider range of piece sizes, for example. Increasing...
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A selection of forest condition indicators for monitoring
Kurt H. Riitters; B.E. Law; R.C. Kucera; A.L. Gallant; R.L. DeVelice; C.J. Palmer
1992-01-01
Regional monitoring and assessments of the health of forested ecosystems require indicators of forest conditions and environmental stresses. Indicator selections depend on objectives and the strategy for data collection and analysis. This paper recommends a set of indicators to signal changes in forest ecosystem distribution, productivity, and disturbance. Additional...
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Biological invasions in forest ecosystems
Andrew M. Liebhold; Eckehard G. Brockerhoff; Susan Kalisz; Martin A. Nuñez; David A. Wardle; Michael J. Wingfield
2017-01-01
Forests play critical roles in global ecosystem processes and provide numerous services to society. But forests are increasingly affected by a variety of human influences, especially those resulting from biological invasions. Species invading forests include woody and herbaceous plants, many animal species including mammals and invertebrates, as well as a variety of...
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Huang, Kun; Wang, Shaoqiang; Zhou, Lei; Wang, Huimin; Zhang, Junhui; Yan, Junhua; Zhao, Liang; Wang, Yanfen; Shi, Peili
2014-01-01
Ecosystem light use efficiency (LUE) is a key factor of production models for gross primary production (GPP) predictions. Previous studies revealed that ecosystem LUE could be significantly enhanced by an increase on diffuse radiation. Under large spatial heterogeneity and increasing annual diffuse radiation in China, eddy covariance flux data at 6 sites across different ecosystems from 2003 to 2007 were used to investigate the impacts of diffuse radiation indicated by the cloudiness index (CI) on ecosystem LUE in grassland and forest ecosystems. Our results showed that the ecosystem LUE at the six sites was significantly correlated with the cloudiness variation (0.24≤R2≤0.85), especially at the Changbaishan temperate forest ecosystem (R2 = 0.85). Meanwhile, the CI values appeared more frequently between 0.8 and 1.0 in two subtropical forest ecosystems (Qianyanzhou and Dinghushan) and were much larger than those in temperate ecosystems. Besides, cloudiness thresholds which were favorable for enhancing ecosystem carbon sequestration existed at the three forest sites, respectively. Our research confirmed that the ecosystem LUE at the six sites in China was positively responsive to the diffuse radiation, and the cloudiness index could be used as an environmental regulator for LUE modeling in regional GPP prediction. PMID:25393629
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Huang, Kun; Wang, Shaoqiang; Zhou, Lei; Wang, Huimin; Zhang, Junhui; Yan, Junhua; Zhao, Liang; Wang, Yanfen; Shi, Peili
2014-01-01
Ecosystem light use efficiency (LUE) is a key factor of production models for gross primary production (GPP) predictions. Previous studies revealed that ecosystem LUE could be significantly enhanced by an increase on diffuse radiation. Under large spatial heterogeneity and increasing annual diffuse radiation in China, eddy covariance flux data at 6 sites across different ecosystems from 2003 to 2007 were used to investigate the impacts of diffuse radiation indicated by the cloudiness index (CI) on ecosystem LUE in grassland and forest ecosystems. Our results showed that the ecosystem LUE at the six sites was significantly correlated with the cloudiness variation (0.24 ≤ R(2) ≤ 0.85), especially at the Changbaishan temperate forest ecosystem (R(2) = 0.85). Meanwhile, the CI values appeared more frequently between 0.8 and 1.0 in two subtropical forest ecosystems (Qianyanzhou and Dinghushan) and were much larger than those in temperate ecosystems. Besides, cloudiness thresholds which were favorable for enhancing ecosystem carbon sequestration existed at the three forest sites, respectively. Our research confirmed that the ecosystem LUE at the six sites in China was positively responsive to the diffuse radiation, and the cloudiness index could be used as an environmental regulator for LUE modeling in regional GPP prediction.
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Ajaz Ahmed, Mukhtar Ahmed; Abd-Elrahman, Amr; Escobedo, Francisco J; Cropper, Wendell P; Martin, Timothy A; Timilsina, Nilesh
2017-09-01
Understanding ecosystem processes and the influence of regional scale drivers can provide useful information for managing forest ecosystems. Examining more local scale drivers of forest biomass and water yield can also provide insights for identifying and better understanding the effects of climate change and management on forests. We used diverse multi-scale datasets, functional models and Geographically Weighted Regression (GWR) to model ecosystem processes at the watershed scale and to interpret the influence of ecological drivers across the Southeastern United States (SE US). Aboveground forest biomass (AGB) was determined from available geospatial datasets and water yield was estimated using the Water Supply and Stress Index (WaSSI) model at the watershed level. Our geostatistical model examined the spatial variation in these relationships between ecosystem processes, climate, biophysical, and forest management variables at the watershed level across the SE US. Ecological and management drivers at the watershed level were analyzed locally to identify whether drivers contribute positively or negatively to aboveground forest biomass and water yield ecosystem processes and thus identifying potential synergies and tradeoffs across the SE US region. Although AGB and water yield drivers varied geographically across the study area, they were generally significantly influenced by climate (rainfall and temperature), land-cover factor1 (Water and barren), land-cover factor2 (wetland and forest), organic matter content high, rock depth, available water content, stand age, elevation, and LAI drivers. These drivers were positively or negatively associated with biomass or water yield which significantly contributes to ecosystem interactions or tradeoff/synergies. Our study introduced a spatially-explicit modelling framework to analyze the effect of ecosystem drivers on forest ecosystem structure, function and provision of services. This integrated model approach facilitates multi-scale analyses of drivers and interactions at the local to regional scale. Copyright © 2017 Elsevier Ltd. All rights reserved.
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The Cooperative Forest Ecosystem Research Program
,
2002-01-01
Changes in priorities for forest management on federal and state lands in the Pacific Northwest have raised many questions about the best ways to manage young-forest stands, riparian areas, and forest landscapes. The Cooperative Forest Ecosystem Research (CFER) Program draws together scientists and managers from the U.S. Geological Survey, Bureau of Land Management, Oregon Department of Forestry, and Oregon State University to find science-based answers to these questions. Managers, researchers, and decisionmakers, working within the CFER program, are helping develop and disseminate the knowledge needed to carry out ecosystem-based management successfully in the Pacific Northwest.
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Origin of the Hawaiian rainforest and its transition states in long-term primary succession
NASA Astrophysics Data System (ADS)
Mueller-Dombois, D.; Boehmer, H. J.
2013-07-01
This paper addresses the question of transition states in the Hawaiian rainforest ecosystem with emphasis on their initial developments. Born among volcanoes in the north central Pacific about 4 million years ago, the Hawaiian rainforest became assembled from spores of algae, fungi, lichens, bryophytes, ferns and from seeds of about 275 flowering plants that over the millennia evolved into ca. 1000 endemic species. Outstanding among the forest builders were the tree ferns (Cibotium spp.) and the 'ōhi'a lehua trees (Metrosideros spp.), which still dominate the Hawaiian rainforest ecosystem today. The structure of this forest is simple. The canopy in closed mature rainforests is dominated by cohorts of Metrosideros polymorpha and the undergrowth by tree fern species of Cibotium. When a new lava flow cuts through this forest, kipuka are formed, i.e., islands of remnant vegetation. On the new volcanic substrate, the assemblage of plant life forms is similar to the assemblage during the evolution of this system. In open juvenile forests, a mat-forming fern, the uluhe fern (Dicranopteris linearis), becomes established. It inhibits further regeneration of the dominant 'ōhi'a tree, thereby reinforcing the cohort structure of the canopy guild. In the later part of its life cycle, the canopy guild breaks down often in synchrony. The trigger is hypothesized to be a climatic perturbation. After the disturbance, the forest becomes reestablished in about 30-40 yr. As the volcanic surfaces age, they go from a mesotrophic to a eutrophic phase, reaching a biophilic nutrient climax by about 1-25 K yr. Thereafter, a regressive oligotrophic phase follows; the soils become exhausted of nutrients. The shield volcanoes break down. Marginally, forest habitats change into bogs and stream ecosystems. The broader 'ōhi'a rainforest redeveloping in the more dissected landscapes of the older islands loses stature, often forming large gaps that are invaded by the aluminum tolerant uluhe fern. The 'ōhi'a trees still thrive on soils rejuvenated from landslides and from Asian dust on the oldest (5 million years old) island Kaua'i but their stature and living biomass is greatly diminished.
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Christin, Zachary; Bagstad, Kenneth J.; Verdone, Michael
2016-01-01
Restoring degraded forests and agricultural lands has become a global conservation priority. A growing number of tools can quantify ecosystem service tradeoffs associated with forest restoration. This evolving “tools landscape” presents a dilemma: more tools are available, but selecting appropriate tools has become more challenging. We present a Restoration Ecosystem Service Tool Selector (RESTS) framework that describes key characteristics of 13 ecosystem service assessment tools. Analysts enter information about their decision context, services to be analyzed, and desired outputs. Tools are filtered and presented based on five evaluative criteria: scalability, cost, time requirements, handling of uncertainty, and applicability to benefit-cost analysis. RESTS uses a spreadsheet interface but a web-based interface is planned. Given the rapid evolution of ecosystem services science, RESTS provides an adaptable framework to guide forest restoration decision makers toward tools that can help quantify ecosystem services in support of restoration.
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Effects of multiple interacting disturbances and salvage logging on forest carbon stocks
Bradford, J.B.; Fraver, S.; Milo, A.M.; D'Amato, A.W.; Palik, B.; Shinneman, D.J.
2012-01-01
Climate change is anticipated to increase the frequency of disturbances, potentially impacting carbon stocks in terrestrial ecosystems. However, little is known about the implications of either multiple disturbances or post-disturbance forest management activities on ecosystem carbon stocks. This study quantified how forest carbon stocks responded to stand-replacing blowdown and wildfire, both individually and in combination with and without post-disturbance salvage operations, in a sub-boreal jack pine ecosystem. Individually, blowdown or fire caused similar decreases in live carbon and total ecosystem carbon. However, whereas blowdown increased carbon in down woody material and forest floor, fire increased carbon in standing snags, a difference that may have consequences for long-term carbon cycling patterns. Fire after the blowdown caused substantial additional reduction in ecosystem carbon stocks, suggesting that potential increases in multiple disturbance events may represent a challenge for sustaining ecosystem carbon stocks. Salvage logging, as examined here, decreased carbon stored in snags and down woody material but had no significant effect on total ecosystem carbon stocks.
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Sean P. Healey; Warren B. Cohen; Yang Zhiqiang; Ken Brewer; Evan Brooks; Noel Gorelick; Mathew Gregory; Alexander Hernandez; Chengquan Huang; Joseph Hughes; Robert Kennedy; Thomas Loveland; Kevin Megown; Gretchen Moisen; Todd Schroeder; Brian Schwind; Stephen Stehman; Daniel Steinwand; James Vogelmann; Curtis Woodcock; Limin Yang; Zhe Zhu
2015-01-01
Forest change information is critical in forest planning, ecosystem modeling, and in updating forest condition maps. The Landsat satellite platform has provided consistent observations of the worldâs ecosystems since 1972. A number of innovative change detection algorithms have been developed to use the Landsat archive to identify and characterize forest change. The...
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Learning in Virtual Forest: A Forest Ecosystem in the Web-Based Learning Environment
ERIC Educational Resources Information Center
Jussila, Terttu; Virtanen, Viivi
2014-01-01
Virtual Forest is a web-based, open-access learning environment about forests designed for primary-school pupils between the ages of 10 and 13 years. It is pedagogically designed to develop an understanding of ecology, to enhance conceptual development and to give a holistic view of forest ecosystems. Various learning tools, such as concept maps,…
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Stephen Handler; Matthew J. Duveneck; Louis Iverson; Emily Peters; Robert M. Scheller; Kirk R. Wythers; Leslie Brandt; Patricia Butler; Maria Janowiak; P. Danielle Shannon; Chris Swanston; Kelly Barrett; Randy Kolka; Casey McQuiston; Brian Palik; Peter B. Reich; Clarence Turner; Mark White; Cheryl Adams; Anthony D' Amato; Suzanne Hagell; Patricia Johnson; Rosemary Johnson; Mike Larson; Stephen Matthews; Rebecca Montgomery; Steve Olson; Matthew Peters; Anantha Prasad; Jack Rajala; Jad Daley; Mae Davenport; Marla R. Emery; David Fehringer; Christopher L. Hoving; Gary Johnson; Lucinda Johnson; David Neitzel; Adena Rissman; Chadwick Rittenhouse; Robert. Ziel
2014-01-01
Forests in northern Minnesota will be affected directly and indirectly by a changing climate over the next 100 years. This assessment evaluates the vulnerability of forest ecosystems in Minnesota's Laurentian Mixed Forest Province to a range of future climates. Information on current forest conditions, observed climate trends, projected climate changes, and...
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NASA Astrophysics Data System (ADS)
Chiesi, M.; Maselli, F.; Moriondo, M.; Fibbi, L.; Bindi, M.; Running, S. W.
2009-04-01
The current paper reports on the development and testing of a methodology capable of simulating the main terms of forest carbon budget (gross primary production, GPP, net primary production, NPP, and net ecosystem exchange, NEE) in the Mediterranean environment. The study area is Tuscany, a region of Central Italy which is covered by forests over about half of its surface. It is peculiar for its extremely heterogeneous morphological and climatic features which ranges from typically Mediterranean to temperate warm or cool according to the altitudinal and latitudinal gradients and the distance from the sea (Rapetti and Vittorini, 1995). The simulation of forest carbon budget is based on the preliminary collection of several data layers to characterize the eco-climatic and forest features of the region (i.e. maps of forest type and volume, daily meteorological data and monthly NDVI-derived FAPAR - fraction of absorbed photosynthetically active radiation - estimates for the years 1999-2003). In particular, the 1:250.000 forest type map describes the distribution of 18 forest classes and was obtained by the Regional Cartographic Service. The volume map, with a 30 m spatial resolution and a mean accuracy of about 90 m3/ha, was produced by combining the available regional forest inventory data and Landsat TM images (Maselli and Chiesi, 2006). Daily meteorological data (minimum and maximum air temperatures and precipitation) were extrapolated by the use of the DAYMET algorithm (Thornton et al., 1997) from measurements taken at existing whether stations for the years 1996-2003 (calibration plus application periods); solar radiation was then estimated by the model MT-CLIM (Thornton et al., 2000). Monthly NDVI-derived FAPAR estimates were obtained using the Spot-VEGETATION satellite sensor data for the whole study period (1999-2003). After the collection of these data layers, a simplified, remote sensing based parametric model (C-Fix), is applied for the production of a reference series of monthly gross primary production (GPP) estimates. In particular this model estimates forest GPP as function of photosynthetically active radiation absorbed by vegetation (Veroustraete et al., 2002) combined with ground based estimates of incoming solar radiation and air temperature. These GPP values are used as reference data to both calibrate and integrate the functions of a more complex bio-geochemical model, BIOME-BGC, which is capable of simulating all main ecosystem processes. This model requires: daily climate data, information on the general environment (i.e. soil, vegetation and site conditions) and parameters describing the ecophysiological characteristics of vegetation. Both C-Fix and BIOME-BGC compute GPP as an expression of total, or potential, productivity of an ecosystem in equilibrium with the environment. This makes the GPP estimates of the two models practically inter-comparable and opens the possibility of using the more accurate GPP estimates of C-Fix to both calibrate BIOME-BGC and stabilize its outputs (Chiesi et al., 2007). In particular, by integrating BIOME-BGC respiration estimates to those of C-Fix, forest fluxes for the entire region are obtained, which are referable to ecosystems at equilibrium (climax) condition. These estimates are converted into NPP and NEE of real forests relying on a specifically developed conceptual framework which uses the ratio of actual over potential stand volume as indicator of ecosystem distance from climax. The accuracy of the estimated net carbon exchanges is finally evaluated against ground data derived from a recent forest inventory and from two eddy covariance flux towers located in Tuscany (San Rossore and Lecceto). The results of both these comparisons were quite positive, indicating the good capability of the method for forest carbon flux estimation in Mediterranean areas.
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Coupling of soil prokaryotic diversity and plant diversity across latitudinal forest ecosystems
NASA Astrophysics Data System (ADS)
Wang, Jun-Tao; Zheng, Yuan-Ming; Hu, Hang-Wei; Li, Jing; Zhang, Li-Mei; Chen, Bao-Dong; Chen, Wei-Ping; He, Ji-Zheng
2016-01-01
The belowground soil prokaryotic community plays a cardinal role in sustaining the stability and functions of forest ecosystems. Yet, the nature of how soil prokaryotic diversity co-varies with aboveground plant diversity along a latitudinal gradient remains elusive. By establishing three hundred 400-m2 quadrats from tropical rainforest to boreal forest in a large-scale parallel study on both belowground soil prokaryote and aboveground tree and herb communities, we found that soil prokaryotic diversity couples with the diversity of herbs rather than trees. The diversity of prokaryotes and herbs responds similarly to environmental factors along the latitudinal gradient. These findings revealed that herbs provide a good predictor of belowground biodiversity in forest ecosystems, and provide new perspective on the aboveground and belowground interactions in forest ecosystems.
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Coupling of soil prokaryotic diversity and plant diversity across latitudinal forest ecosystems.
Wang, Jun-Tao; Zheng, Yuan-Ming; Hu, Hang-Wei; Li, Jing; Zhang, Li-Mei; Chen, Bao-Dong; Chen, Wei-Ping; He, Ji-Zheng
2016-01-19
The belowground soil prokaryotic community plays a cardinal role in sustaining the stability and functions of forest ecosystems. Yet, the nature of how soil prokaryotic diversity co-varies with aboveground plant diversity along a latitudinal gradient remains elusive. By establishing three hundred 400-m(2) quadrats from tropical rainforest to boreal forest in a large-scale parallel study on both belowground soil prokaryote and aboveground tree and herb communities, we found that soil prokaryotic diversity couples with the diversity of herbs rather than trees. The diversity of prokaryotes and herbs responds similarly to environmental factors along the latitudinal gradient. These findings revealed that herbs provide a good predictor of belowground biodiversity in forest ecosystems, and provide new perspective on the aboveground and belowground interactions in forest ecosystems.
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[Carbon sequestration status of forest ecosystems in Ningxia Hui Autonomous Region].
Gao, Yang; Jin, Jing-Wei; Cheng, Ji-Min; Su, Ji-Shuai; Zhu, Ren-Bin; Ma, Zheng-Rui; Liu, Wei
2014-03-01
Based on the data of Ningxia Hui Autonomous Region forest resources inventory, field investigation and laboratory analysis, this paper studied the carbon sequestration status of forest ecosystems in Ningxia region, estimated the carbon density and storage of forest ecosystems, and analyzed their spatial distribution characteristics. The results showed that the biomass of each forest vegetation component was in the order of arbor layer (46.64 Mg x hm(-2)) > litterfall layer (7.34 Mg x hm(-2)) > fine root layer (6.67 Mg x hm(-2)) > shrub-grass layer (0.73 Mg x hm(-2)). Spruce (115.43 Mg x hm(-2)) and Pinus tabuliformis (94.55 Mg x hm(-2)) had higher vegetation biomasses per unit area than other tree species. Over-mature forest had the highest arbor carbon density among the forests with different ages. However, the young forest had the highest arbor carbon storage (1.90 Tg C) due to its widest planted area. Overall, the average carbon density of forest ecosystems in Ningxia region was 265.74 Mg C x hm(-2), and the carbon storage was 43.54 Tg C. Carbon density and storage of vegetation were 27.24 Mg C x hm(-2) and 4.46 Tg C, respectively. Carbon storage in the soil was 8.76 times of that in the vegetation. In the southern part of Ningxia region, the forest carbon storage was higher than in the northern part, where the low C storage was mainly related to the small forest area and young forest age structure. With the improvement of forest age structure and the further implementation of forestry ecoengineering, the forest ecosystems in Ningxia region would achieve a huge carbon sequestration potential.
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The roles of hydraulic and carbon stress in a widespread climate-induced forest die-off
Anderegg, William R. L.; Berry, Joseph A.; Smith, Duncan D.; Sperry, John S.; Anderegg, Leander D. L.; Field, Christopher B.
2012-01-01
Forest ecosystems store approximately 45% of the carbon found in terrestrial ecosystems, but they are sensitive to climate-induced dieback. Forest die-off constitutes a large uncertainty in projections of climate impacts on terrestrial ecosystems, climate–ecosystem interactions, and carbon-cycle feedbacks. Current understanding of the physiological mechanisms mediating climate-induced forest mortality limits the ability to model or project these threshold events. We report here a direct and in situ study of the mechanisms underlying recent widespread and climate-induced trembling aspen (Populus tremuloides) forest mortality in western North America. We find substantial evidence of hydraulic failure of roots and branches linked to landscape patterns of canopy and root mortality in this species. On the contrary, we find no evidence that drought stress led to depletion of carbohydrate reserves. Our results illuminate proximate mechanisms underpinning recent aspen forest mortality and provide guidance for understanding and projecting forest die-offs under climate change. PMID:22167807
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Arroyo-Rodríguez, Víctor; Melo, Felipe P L; Martínez-Ramos, Miguel; Bongers, Frans; Chazdon, Robin L; Meave, Jorge A; Norden, Natalia; Santos, Bráulio A; Leal, Inara R; Tabarelli, Marcelo
2017-02-01
Old-growth tropical forests are being extensively deforested and fragmented worldwide. Yet forest recovery through succession has led to an expansion of secondary forests in human-modified tropical landscapes (HMTLs). Secondary forests thus emerge as a potential repository for tropical biodiversity, and also as a source of essential ecosystem functions and services in HMTLs. Such critical roles are controversial, however, as they depend on successional, landscape and socio-economic dynamics, which can vary widely within and across landscapes and regions. Understanding the main drivers of successional pathways of disturbed tropical forests is critically needed for improving management, conservation, and restoration strategies. Here, we combine emerging knowledge from tropical forest succession, forest fragmentation and landscape ecology research to identify the main driving forces shaping successional pathways at different spatial scales. We also explore causal connections between land-use dynamics and the level of predictability of successional pathways, and examine potential implications of such connections to determine the importance of secondary forests for biodiversity conservation in HMTLs. We show that secondary succession (SS) in tropical landscapes is a multifactorial phenomenon affected by a myriad of forces operating at multiple spatio-temporal scales. SS is relatively fast and more predictable in recently modified landscapes and where well-preserved biodiversity-rich native forests are still present in the landscape. Yet the increasing variation in landscape spatial configuration and matrix heterogeneity in landscapes with intermediate levels of disturbance increases the uncertainty of successional pathways. In landscapes that have suffered extensive and intensive human disturbances, however, succession can be slow or arrested, with impoverished assemblages and reduced potential to deliver ecosystem functions and services. We conclude that: (i) succession must be examined using more comprehensive explanatory models, providing information about the forces affecting not only the presence but also the persistence of species and ecological groups, particularly of those taxa expected to be extirpated from HMTLs; (ii) SS research should integrate new aspects from forest fragmentation and landscape ecology research to address accurately the potential of secondary forests to serve as biodiversity repositories; and (iii) secondary forest stands, as a dynamic component of HMTLs, must be incorporated as key elements of conservation planning; i.e. secondary forest stands must be actively managed (e.g. using assisted forest restoration) according to conservation goals at broad spatial scales. © 2015 Cambridge Philosophical Society.
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Loss of functional diversity of ant assemblages in secondary tropical forests.
Bihn, Jochen H; Gebauer, Gerhard; Brandl, Roland
2010-03-01
Secondary forests and plantations increasingly dominate the tropical wooded landscape in place of primary forests. The expected reduction of biodiversity and its impact on ecological functions provided by these secondary forests are of major concern to society and ecologists. The potential effect of biodiversity loss on ecosystem functioning depends largely on the associated loss in the functional diversity of animal and plant assemblages, i.e., the degree of functional redundancy among species. However, the relationship between species and functional diversity is still poorly documented for most ecosystems. Here, we analyze how changes in the species diversity of ground-foraging ant assemblages translate into changes of functional diversity along a successional gradient of secondary forests in the Atlantic Forest of Brazil. Our analysis uses continuous measures of functional diversity and is based on four functional traits related to resource use of ants: body size, relative eye size, relative leg length, and trophic position. We find a strong relationship between species and functional diversity, independent of the functional traits used, with no evidence for saturation in this relationship. Recovery of species richness and diversity of ant assemblages in tropical secondary forests was accompanied by a proportional increase of functional richness and diversity of assemblages. Moreover, our results indicate that the increase in functional diversity along the successional gradient of secondary forests is primarily driven by rare species, which are functionally unique. The observed loss of both species and functional diversity in secondary forests offers no reason to believe that the ecological functions provided by secondary forests are buffered against species loss through functional redundancy.
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Economic vulnerability of timber resources to forest fires.
y Silva, Francisco Rodríguez; Molina, Juan Ramón; González-Cabán, Armando; Machuca, Miguel Ángel Herrera
2012-06-15
The temporal-spatial planning of activities for a territorial fire management program requires knowing the value of forest ecosystems. In this paper we extend to and apply the economic valuation principle to the concept of economic vulnerability and present a methodology for the economic valuation of the forest production ecosystems. The forest vulnerability is analyzed from criteria intrinsically associated to the forest characterization, and to the potential behavior of surface fires. Integrating a mapping process of fire potential and analytical valuation algorithms facilitates the implementation of fire prevention planning. The availability of cartography of economic vulnerability of the forest ecosystems is fundamental for budget optimization, and to help in the decision making process. Published by Elsevier Ltd.
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Li, Yong; Niu, Shuli; Yu, Guirui
2016-02-01
Nitrogen (N) and phosphorus (P), either individually or in combination, have been demonstrated to limit biomass production in terrestrial ecosystems. Field studies have been extensively synthesized to assess global patterns of N impacts on terrestrial ecosystem processes. However, to our knowledge, no synthesis has been done so far to reveal global patterns of P impacts on terrestrial ecosystems, especially under different nitrogen (N) levels. Here, we conducted a meta-analysis of impacts of P addition, either alone or with N addition, on aboveground (AGB) and belowground biomass production (BGB), plant and soil P concentrations, and N : P ratio in terrestrial ecosystems. Overall, our meta-analysis quantitatively confirmed existing notions: (i) colimitation of N and P on biomass production and (ii) more P limitation in tropical forest than other ecosystems. More importantly, our analysis revealed new findings: (i) P limitation on biomass production was aggravated by N enrichment and (ii) plant P concentration was a better indicator of P limitation than soil P availability. Specifically, P addition increased AGB and BGB by 34% and 13%, respectively. The effect size of P addition on biomass production was larger in tropical forest than grassland, wetland, and tundra and varied with P fertilizer forms, P addition rates, or experimental durations. The P-induced increase in biomass production and plant P concentration was larger under elevated than ambient N. Our findings suggest that the global limitation of P on biomass production will become severer under increasing N fertilizer and deposition in the future. © 2015 John Wiley & Sons Ltd.
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David S. Ellsworth
1999-01-01
Sugar maple-dominated forest ecosystems in the northeastern U.S. have been receiving precipitation nitrogen (N) inputs of 15 -20 kg N ha1 year1 since at least the mid 1980s sustained chronic N inputs of this magnitude into nutrient-poor forest ecosystems may cause eutrophication and affect ecosystem functioning as well as...
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Salim Belyazid; Scott Bailey; Harald Sverdrup
2010-01-01
The Hubbard Brook Ecosystem Study presents a unique opportunity for studying long-term ecosystem responses to changes in anthropogenic factors. Following industrialisation and the intensification of agriculture, the Hubbard Brook Experimental Forest (HBEF) has been subject to increased loads of atmospheric deposition, particularly sulfur and nitrogen. The deposition of...
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The Mammoth-June Ecosystem Management Project, Inyo National Forest
Connie Millar
1996-01-01
The Sierra Nevada Ecosystem Project (SNEP) case-study assessmentof the Mammoth-June Ecosystem Management Project(MJEMP) was undertaken to review and analyze the efficacy of alocal landscape analysis in achieving ecosystem-management objectivesin the Sierra Nevada. Of primary interest to SNEP was applicationof the new U.S. Forest Service (USFS) regional process...
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Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-03
...-Challis National Forest, ID; Upper North Fork HFRA Ecosystem Restoration Project Environmental Impact... improve the health of the ecosystem and reach the desired future condition. DATES: Comments concerning the... Ecosystem Restoration Project EIS, P.O. Box 180, 11 Casey Rd., North Fork, ID 83466. Comments may also be...
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Available fuel dynamics in nine contrasting forest ecosystems in North America
Soung-Ryoul Ryu; Jiquan Chen; Thomas R. Crow; Sari C. Saunders
2004-01-01
Available fuel and its dynamics, both of which affect fire behavior in forest ecosystems, are direct products of ecosystem production, decomposition, and disturbances. Using published ecosystem models and equations, we developed a simulation model to evaluate the effects of dynamics of aboveground net primary production (ANPP), carbon allocation, residual slash,...
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Using an Ecological Land Hierarchy to Predict Seasonal-Wetland Abundance in Upland Forests
Brian J. Palik; Richard Buech; Leanne Egeland
2003-01-01
Hierarchy theory, when applied to landscapes, predicts that broader-scale ecosystems constrain the development of finer-scale, nested ecosystems. This prediction finds application in hierarchical land classifications. Such classifications typically apply to physiognomically similar ecosystems, or ecological land units, e.g., a set of multi-scale forest ecosystems. We...
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Greenhouse gas exchange in tropical mountain ecosystems in Tanzania
NASA Astrophysics Data System (ADS)
Gerschlauer, Friederike; Kikoti, Imani; Kiese, Ralf
2014-05-01
Tropical mountain ecosystems with their mostly immense biodiversity are important regions for natural resources but also for agricultural production. Their supportive ecosystem processes are particularly vulnerable to the combined impacts of global warming and the conversion of natural to human-modified landscapes. Data of impacts of climate and land use change on soil-atmosphere interactions due to GHG (CO2, CH4, and N2O) exchange from these ecosystems are still scarce, in particular for Africa. Tropical forest soils are underestimated as sinks for atmospheric CH4 with regard to worldwide GHG budgets (Werner et al. 2007, J GEOPHYS RES Vol. 112). Even though these soils are an important source for the atmospheric N2O budget, N2O emissions from tropical forest ecosystems are still poorly characterized (Castaldi et al. 2013, Biogeosciences 10). To obtain an insight of GHG balances of selected ecosystems soil-atmosphere exchange of N2O, CH4 and CO2 was investigated along the southern slope of Mt. Kilimanjaro, Tanzania. We will present results for tropical forests in three different altitudes (lower montane, Ocotea, and Podocarpus forest), home garden (extensive agro-forestry), and coffee plantation (intensive agro-forestry). Therefore we used a combined approach consisting of a laboratory parameterization experiment (3 temperature and 2 moisture levels) and in situ static chamber measurements for GHG exchange. Field measurements were conducted during different hygric seasons throughout two years. Seasonal variation of temperature and especially of soil moisture across the different ecosystems resulted in distinct differences in GHG exchange. In addition environmental parameters like soil bulk density and substrate availability varying in space strongly influenced the GHG fluxes within sites. The results from parameterization experiments and in situ measurements show that natural forest ecosystems and extensive land use had higher uptakes of CH4. For the investigated forest ecosystems we found considerable differences in soil sink strength for CH4. N2O emissions were highest in natural forest ecosystems even though N input in the intensively managed system was considerably higher. Highest N2O efflux rates were identified in the region of highest mean annual precipitation. CO2 emissions reduced from managed to natural ecosystems. In general an increase in temperature as well as in soil moisture caused higher GHG fluxes throughout all investigated natural and managed ecosystems. With increasing altitude of the investigated forests GHG emissions reduced overall.
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Forest habitat conservation in Africa using commercially important insects.
Raina, Suresh Kumar; Kioko, Esther; Zethner, Ole; Wren, Susie
2011-01-01
African forests, which host some of the world's richest biodiversity, are rapidly diminishing. The loss of flora and fauna includes economically and socially important insects. Honey bees and silk moths, grouped under commercial insects, are the source for insect-based enterprises that provide income to forest-edge communities to manage the ecosystem. However, to date, research output does not adequately quantify the impact of such enterprises on buffering forest ecosystems and communities from climate change effects. Although diseases/pests of honey bees and silk moths in Africa have risen to epidemic levels, there is a dearth of practical research that can be utilized in developing effective control mechanisms that support the proliferation of these commercial insects as pollinators of agricultural and forest ecosystems. This review highlights the critical role of commercial insects within the environmental complexity of African forest ecosystems, in modern agroindustry, and with respect to its potential contribution to poverty alleviation and pollination services. It identifies significant research gaps that exist in understanding how insects can be utilized as ecosystem health indicators and nurtured as integral tools for important socioeconomic and industrial gains.
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Carbon stocks and potential carbon storage in the mangrove forests of China.
Liu, Hongxiao; Ren, Hai; Hui, Dafeng; Wang, Wenqing; Liao, Baowen; Cao, Qingxian
2014-01-15
Mangrove forests provide important ecosystem services, and play important roles in terrestrial and oceanic carbon (C) cycling. Although the C stocks or storage in terrestrial ecosystems in China have been frequently assessed, the C stocks in mangrove forests have often been overlooked. In this study, we estimated the C stocks and the potential C stocks in China's mangrove forests by combining our own field data with data from the National Mangrove Resource Inventory Report and from other published literature. The results indicate that mangrove forests in China store about 6.91 ± 0.57 Tg C, of which 81.74% is in the top 1 m soil, 18.12% in the biomass of mangrove trees, and 0.08% in the ground layer (i.e. mangrove litter and seedlings). The potential C stocks are as high as 28.81 ± 4.16 Tg C. On average, mangrove forests in China contain 355.25 ± 82.19 Mg C ha(-1), which is consistent with the global average of mangrove C density at similar latitudes, but higher than the average C density in terrestrial forests in China. Our results suggest that C storage in mangroves can be increased by selecting high C-density species for afforestation and stand improvement, and even more by increasing the mangrove area. The information gained in this study will facilitate policy decisions concerning the restoration of mangrove forests in China. Copyright © 2013 Elsevier Ltd. All rights reserved.
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NASA Astrophysics Data System (ADS)
Brooks, P. D.; Harpold, A. A.; Biederman, J. A.; Litvak, M. E.; Broxton, P. D.; Gochis, D.; Molotch, N. P.; Troch, P. A.; Ewers, B. E.
2012-12-01
Unprecedented levels of insect induced tree mortality and massive wildfires both have spread through the forests of Western North America over the last decade. Warming temperatures and increased drought stress have been implicated as major factors in the increasing spatial extent and frequency of these forest disturbances, but it is unclear how simultaneous changes in forest structure and climate will interact to affect either downstream water resources or the regeneration and recovery of forested ecosystems. Because both streamflow and ecosystem productivity depend on seasonal snowmelt, a critical knowledge gap exists in how these disturbances will interact with a changing climate to control to the amount, timing, and the partitioning of seasonal snow cover This presentation will address this knowledge gap by synthesizing recent work on snowpack dynamics and ecosystem productivity from seasonally snow-covered forests along a gradient of snow depth and duration from Arizona to Montana. These include undisturbed sites, recently burned forests, and areas of extensive insect-induced forest mortality. Both before-after and control-impacted studies of forest disturbance on snow accumulation and ablation suggest that the spatial scale of snow distribution increases following disturbance, but net snow water input likely will not increase under a warming climate. While forest disturbance changes spatial scale of snowpack partitioning, the amount and especially the timing of snow cover accumulation and ablation are strongly related to interannual variability in ecosystem productivity with both earlier snowmelt and later snow accumulation associated with decreased carbon uptake. These observations suggest that the ecosystem services of water provision and carbon storage may be very different in the forests that regenerate after disturbance.
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NASA Astrophysics Data System (ADS)
Tekalign, Meron; Muys, Bart; Nyssen, Jan; Poesen, Jean
2014-05-01
In the central highlands of Ethiopia, deforestation and forest degradation are occurring and accelerating during the last century. The high population pressure is the most repeatedly mentioned reason. However, in the past 30 years researchers agreed that the absence of institutions, which could define the access rights to particular forest resources, is another underlying cause of forest depletion and loss. Changing forest areas into different land use types is affecting the biodiversity, which is manifested through not proper functioning of ecosystem services. Menagesha Suba forest, the focus of this study has been explored from various perspectives. However the social dimension and its interaction with the ecology have been addressed rarely. This research uses a combined theoretical framework of Ecosystem Services and that of Resilience thinking for understanding the complex social-ecological interactions in the forest and its influence on ecosystem services. For understanding the history and extent of land use land cover changes, in-depth literature review and a GIS and remote sensing analysis will be made. The effect of forest conversion into plantation and agricultural lands on soil and above ground carbon sequestration, fuel wood and timber products delivery will be analyzed with the accounting of the services on five land use types. The four ecosystem services to be considered are Supporting, Provisioning, Regulating, and Cultural services as set by the Millennium Ecosystem Assessment. A resilience based participatory framework approach will be used to analyze how the social and ecological systems responded towards the drivers of change that occurred in the past. The framework also will be applied to predict future uncertainties. Finally this study will focus on the possible interventions that could contribute to the sustainable management and conservation of the forest. An ecosystem services trade-off analysis and an environmental valuation of the water regulation and soil erosion control services will be made to propose solutions for increasing the social-ecological system resilience of Menagesha Suba forest.
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Wiezik, Michal; Svitok, Marek; Wieziková, Adela; Dovčiak, Martin
2015-01-01
Global or regional environmental changes in climate or land use have been increasingly implied in shifts in boundaries (ecotones) between adjacent ecosystems such as beech or oak-dominated forests and forest-steppe ecotones that frequently co-occur near the southern range limits of deciduous forest biome in Europe. Yet, our ability to detect changes in biological communities across these ecosystems, or to understand their environmental drivers, can be hampered when different sampling methods are required to characterize biological communities of the adjacent but ecologically different ecosystems. Ants (Hymenoptera: Formicidae) have been shown to be particularly sensitive to changes in temperature and vegetation and they require different sampling methods in closed vs. open habitats. We compared ant assemblages of closed-forests (beech- or oak-dominated) and open forest-steppe habitats in southwestern Carpathians using methods for closed-forest (litter sifting) and open habitats (pitfall trapping), and developed an integrated sampling approach to characterize changes in ant assemblages across these adjacent ecosystems. Using both methods, we collected 5,328 individual ant workers from 28 species. Neither method represented ant communities completely, but pitfall trapping accounted for more species (24) than litter sifting (16). Although pitfall trapping characterized differences in species richness and composition among the ecosystems better, with beech forest being most species poor and ecotone most species rich, litter sifting was more successful in identifying characteristic litter-dwelling species in oak-dominated forest. The integrated sampling approach using both methods yielded more accurate characterization of species richness and composition, and particularly so in species-rich forest-steppe habitat where the combined sample identified significantly higher number of species compared to either of the two methods on their own. Thus, an integrated sampling approach should be used to fully characterize changes in ant assemblages across ecosystem boundaries, or with vegetation change over time, and particularly so in species-rich habitats such as forest-steppe ecotones. PMID:26226140
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Wiezik, Michal; Svitok, Marek; Wieziková, Adela; Dovčiak, Martin
2015-01-01
Global or regional environmental changes in climate or land use have been increasingly implied in shifts in boundaries (ecotones) between adjacent ecosystems such as beech or oak-dominated forests and forest-steppe ecotones that frequently co-occur near the southern range limits of deciduous forest biome in Europe. Yet, our ability to detect changes in biological communities across these ecosystems, or to understand their environmental drivers, can be hampered when different sampling methods are required to characterize biological communities of the adjacent but ecologically different ecosystems. Ants (Hymenoptera: Formicidae) have been shown to be particularly sensitive to changes in temperature and vegetation and they require different sampling methods in closed vs. open habitats. We compared ant assemblages of closed-forests (beech- or oak-dominated) and open forest-steppe habitats in southwestern Carpathians using methods for closed-forest (litter sifting) and open habitats (pitfall trapping), and developed an integrated sampling approach to characterize changes in ant assemblages across these adjacent ecosystems. Using both methods, we collected 5,328 individual ant workers from 28 species. Neither method represented ant communities completely, but pitfall trapping accounted for more species (24) than litter sifting (16). Although pitfall trapping characterized differences in species richness and composition among the ecosystems better, with beech forest being most species poor and ecotone most species rich, litter sifting was more successful in identifying characteristic litter-dwelling species in oak-dominated forest. The integrated sampling approach using both methods yielded more accurate characterization of species richness and composition, and particularly so in species-rich forest-steppe habitat where the combined sample identified significantly higher number of species compared to either of the two methods on their own. Thus, an integrated sampling approach should be used to fully characterize changes in ant assemblages across ecosystem boundaries, or with vegetation change over time, and particularly so in species-rich habitats such as forest-steppe ecotones.
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Toward a methodical framework for comprehensively assessing forest multifunctionality.
Trogisch, Stefan; Schuldt, Andreas; Bauhus, Jürgen; Blum, Juliet A; Both, Sabine; Buscot, François; Castro-Izaguirre, Nadia; Chesters, Douglas; Durka, Walter; Eichenberg, David; Erfmeier, Alexandra; Fischer, Markus; Geißler, Christian; Germany, Markus S; Goebes, Philipp; Gutknecht, Jessica; Hahn, Christoph Zacharias; Haider, Sylvia; Härdtle, Werner; He, Jin-Sheng; Hector, Andy; Hönig, Lydia; Huang, Yuanyuan; Klein, Alexandra-Maria; Kühn, Peter; Kunz, Matthias; Leppert, Katrin N; Li, Ying; Liu, Xiaojuan; Niklaus, Pascal A; Pei, Zhiqin; Pietsch, Katherina A; Prinz, Ricarda; Proß, Tobias; Scherer-Lorenzen, Michael; Schmidt, Karsten; Scholten, Thomas; Seitz, Steffen; Song, Zhengshan; Staab, Michael; von Oheimb, Goddert; Weißbecker, Christina; Welk, Erik; Wirth, Christian; Wubet, Tesfaye; Yang, Bo; Yang, Xuefei; Zhu, Chao-Dong; Schmid, Bernhard; Ma, Keping; Bruelheide, Helge
2017-12-01
Biodiversity-ecosystem functioning (BEF) research has extended its scope from communities that are short-lived or reshape their structure annually to structurally complex forest ecosystems. The establishment of tree diversity experiments poses specific methodological challenges for assessing the multiple functions provided by forest ecosystems. In particular, methodological inconsistencies and nonstandardized protocols impede the analysis of multifunctionality within, and comparability across the increasing number of tree diversity experiments. By providing an overview on key methods currently applied in one of the largest forest biodiversity experiments, we show how methods differing in scale and simplicity can be combined to retrieve consistent data allowing novel insights into forest ecosystem functioning. Furthermore, we discuss and develop recommendations for the integration and transferability of diverse methodical approaches to present and future forest biodiversity experiments. We identified four principles that should guide basic decisions concerning method selection for tree diversity experiments and forest BEF research: (1) method selection should be directed toward maximizing data density to increase the number of measured variables in each plot. (2) Methods should cover all relevant scales of the experiment to consider scale dependencies of biodiversity effects. (3) The same variable should be evaluated with the same method across space and time for adequate larger-scale and longer-time data analysis and to reduce errors due to changing measurement protocols. (4) Standardized, practical and rapid methods for assessing biodiversity and ecosystem functions should be promoted to increase comparability among forest BEF experiments. We demonstrate that currently available methods provide us with a sophisticated toolbox to improve a synergistic understanding of forest multifunctionality. However, these methods require further adjustment to the specific requirements of structurally complex and long-lived forest ecosystems. By applying methods connecting relevant scales, trophic levels, and above- and belowground ecosystem compartments, knowledge gain from large tree diversity experiments can be optimized.
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Plant ecophysiology and forest response to global change.
Buchmann, N
2002-11-01
There are many ways of studying forest responses to global change. Most current national and international programs focus on net gas exchange of the terrestrial biosphere and are typically interdisciplinary, multi-scale projects. Key objectives of these programs are surprisingly similar to those of classical plant ecophysiology studies, i.e., to explore functional relationships of plant or plant community responses to environmental change. Thus, common research questions that link plant ecophysiology to ecosystem functioning can be identified for both research communities, promising complementarity and synergism for joint research projects. Although some well-established ecophysiological relationships, such as light responses or stomatal limitations of photosynthetic gas exchange, are currently employed in many ecosystem-scale net flux studies for gap-filling or modeling, only 14% (n = 27) of all eddy covariance flux studies in forests (n = 196; published between 1992 and April 2002) include plant ecophysiological measurements (n = 24) or biomass and growth estimates (n = 8). Generally, emphasis is on CO2 exchange measurements at various scales (foliage, shoots, branches; n = 14) and water relations measurements (n = 11). These measurements do not fully support the typical parameterization of stand and regional models, which often need information on canopy architecture and nitrogen nutrition. By means of a complementary research approach, valuable information can be acquired that is unobtainable by means of a single approach. This additional information is important for the identification of underlying biotic and environmental drivers, for the regulation of net ecosystem fluxes and their partitioning, and the independent validation of measured net ecosystem fluxes. Thus, combining micrometeorology and ecophysiology at flux sites is strongly recommended for ecosystem functioning studies.
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The Use of Thermal Remote Sensing to Study Thermodynamics of Ecosystem Development
NASA Technical Reports Server (NTRS)
Luvall, Jeffrey C.; Rickman, Doug L.; Arnold, James E. (Technical Monitor)
2000-01-01
Thermal remote sensing can provide environmental measuring tools with capabilities for measuring ecosystem development and integrity. Recent advances in applying principles of nonequilibrium thermodynamics to ecology provide fundamental insights into energy partitioning in ecosystems. Ecosystems are nonequilibrium systems, open to material and energy flows, which grow and develop structures and processes to increase energy degradation. More developed terrestrial ecosystems will be more effective at dissipating the solar gradient (degrading its energy content). This can be measured by the effective surface temperature of the ecosystem on a landscape scale. A series of airborne thermal infrared multispectral scanner data were collected from several forested ecosystems ranging from a western US douglas-fir forest to a tropical rain forest in Costa Rica. These data were used to develop measures of ecosystem development and integrity based on surface temperature.
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Thermal Remote Sensing and the Thermodynamics of Ecosystems Development
NASA Technical Reports Server (NTRS)
Luvall, Jeffrey C.; Kay, James J.; Fraser, Roydon F.; Goodman, H. Michael (Technical Monitor)
2001-01-01
Thermal remote sensing can provide environmental measuring tools with capabilities for measuring ecosystem development and integrity. Recent advances in applying principles of nonequilibrium thermodynamics to ecology provide fundamental insights into energy partitioning in ecosystems. Ecosystems are nonequilibrium systems, open to material and energy flows, which grow and develop structures and processes to increase energy degradation. More developed terrestrial ecosystems will be more effective at dissipating the solar gradient (degrading its energy content). This can be measured by the effective surface temperature of the ecosystem on a landscape scale. A series of airborne thermal infrared multispectral scanner data were collected from several forested ecosystems ranging from a western US douglas-fir forest to a tropical rain forest in Costa Rica. Also measured were agriculture systems. These data were used to develop measures of ecosystem development and integrity based on surface temperature.
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Global sensitivity analysis of DRAINMOD-FOREST, an integrated forest ecosystem model
Shiying Tian; Mohamed A. Youssef; Devendra M. Amatya; Eric D. Vance
2014-01-01
Global sensitivity analysis is a useful tool to understand process-based ecosystem models by identifying key parameters and processes controlling model predictions. This study reported a comprehensive global sensitivity analysis for DRAINMOD-FOREST, an integrated model for simulating water, carbon (C), and nitrogen (N) cycles and plant growth in lowland forests. The...
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Forest vegetation management and protection of stream quality
Jerry L. Michael
2002-01-01
Globally, forest management activities significantly alter portions of the forest ecosystem on a temporal scale at the local level. Along with this alteration in the landscape comes changes in wildlife habitat and potentially the associated aquatic ecosystem. Most timber producing countries in the world have instituted forest regulations in an effort to respond to...
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Ponderosa pine forest structure and northern goshawk reproduction: Response to Beier et al
Richard T. Reynolds; Douglas A. Boyce; Russell T. Graham
2012-01-01
Ecosystem-based forest management requires long planning horizons to incorporate forest dynamics - changes resulting from vegetation growth and succession and the periodic resetting of these by natural and anthropogenic disturbances such as fire, wind, insects, and timber harvests. Given these dynamics, ecosystem-based forest management plans should specify desired...
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Economic vulnerability of timber resources to forest fires
Francisco Rodriguez y Silva; Juan Ramon Molina; Armando Gonzalez-Caban; Miguel Angel Herrera Machuca
2012-01-01
The temporal-spatial planning of activities for a territorial fire management program requires knowing the value of forest ecosystems. In this paper we extend to and apply the economic valuation principle to the concept of economic vulnerability and present a methodology for the economic valuation of the forest production ecosystems. The forest vulnerability is...
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Integrating forest products with ecosystem services: a global perspective
Robert L. Deal; Rachel White
2012-01-01
Around the world forests provide a broad range of vital ecosystem services. Sustainable forest management and forest products play an important role in global carbon management, but one of the major forestry concerns worldwide is reducing the loss of forestland from development. Currently, deforestation accounts for approximately 20% of total greenhouse gas emissions....
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Effects of forest harvest on biogeochemical processes in the Caspar Creek watershed
Randy A. Dahlgren
1998-01-01
Water quality and long-term sustainability are major components addressed within the ecosystem approach to forest management. Forest harvest practices are often implicated as having adverse impacts on sensitive aquatic communities and on the long-term sustainability of forest ecosystems. While careless harvest practices can certainly cause adverse impacts, proper...
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Managing ecosystems for forest health: An approach and the effects on uses and values
Chadwick D. Oliver; Dennis E. Ferguson; Alan E. Harvey; Herbert S. Malany; John M. Mandzak; Robert W. Mutch
1994-01-01
Forest health is most appropriately based on the scientific paradigm of dynamic, constantly changing forest ecosystems. Many forests in the Inland West now support high levels of insect infestations, disease epidemics, fire susceptibilities, and imbalances in stand structures and habitats because of natural processes and past management practices. Impending,...
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Long-term trends from ecosystem research at the Hubbard Brook Experimental Forest
John L. Campbell; Charles T. Driscoll; Christopher Eagar; Gene E. Likens; Thomas G. Siccama; Chris E. Johnson; Timothy J. Fahey; Steven P. Hamburg; Richard T. Holmes; Amey S. Bailey; Donald C. Buso
2007-01-01
Summarizes 52 years of collaborative, long-term research conducted at the Hubbard Brook (NH) Experimental Forest on ecosystem response to disturbances such as air pollution, climate change, forest disturbance, and forest management practices. Also provides explanations of some of the trends and lists references from scientific literature for further reading.
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[Assessment on the changing conditions of ecosystems in key ecological function zones in China].
Huang, Lin; Cao, Wei; Wu, Dan; Gong, Guo-li; Zhao, Guo-song
2015-09-01
In this paper, the dynamics of ecosystem macrostructure, qualities and core services during 2000 and 2010 were analyzed for the key ecological function zones of China, which were classified into four types of water conservation, soil conservation, wind prevention and sand fixation, and biodiversity maintenance. In the water conservation ecological function zones, the areas of forest and grassland ecosystems were decreased whereas water bodies and wetland were increased in the past 11 years, and the water conservation volume of forest, grassland and wetland ecosystems increased by 2.9%. This region needs to reverse the decreasing trends of forest and grassland ecosystems. In the soil conservation ecological function zones, the area of farmland ecosystem was decreased, and the areas of forest, grassland, water bodies and wetland ecosystems were increased. The total amount of the soil erosion was reduced by 28.2%, however, the soil conservation amount of ecosystems increased by 38.1%. In the wind prevention and sand fixation ecological function zones, the areas of grassland, water bodies and wetland ecosystems were decreased, but forest and farmland ecosystems were increased. The unit amount of the soil. wind erosion was reduced and the sand fixation amount of ecosystems increased lightly. In this kind of region that is located in arid and semiarid areas, ecological conservation needs to reduce farmland area and give priority to the protection of the original ecological system. In the biodiversity maintenance ecological function zones, the areas of grassland and desert ecosystems were decreased and other types were increased. The human disturbances showed a weakly upward trend and needs to be reduced. The key ecological function zones should be aimed at the core services and the protecting objects, to assess quantitatively on the effectiveness of ecosystem conservation and improvement.
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Caputo, Jesse; Beier, Colin D; Groffman, Peter M; Burns, Douglas A.; Beall, Frederick D; Hazlett, Paul W.; Yorks, Thad E
2016-01-01
Demand for woody biomass fuels is increasing amidst concerns about global energy security and climate change, but there may be negative implications of increased harvesting for forest ecosystem functions and their benefits to society (ecosystem services). Using new methods for assessing ecosystem services based on long-term experimental research, post-harvest changes in ten potential benefits were assessed for ten first-order northern hardwood forest watersheds at three long-term experimental research sites in northeastern North America. As expected, we observed near-term tradeoffs between biomass provision and greenhouse gas regulation, as well as tradeoffs between intensive harvest and the capacity of the forest to remediate nutrient pollution. In both cases, service provision began to recover along with the regeneration of forest vegetation; in the case of pollution remediation, the service recovered to pre-harvest levels within 10 years. By contrast to these two services, biomass harvesting had relatively nominal and transient impacts on other ecosystem services. Our results are sensitive to empirical definitions of societal demand, including methods for scaling societal demand to ecosystem units, which are often poorly resolved. Reducing uncertainty around these parameters can improve confidence in our results and increase their relevance for decision-making. Our synthesis of long-term experimental studies provides insights on the social-ecological resilience of managed forest ecosystems to multiple drivers of change.
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NASA Astrophysics Data System (ADS)
Silver, W. L.; Smith, W. K.; Parton, W. J.; Wieder, W. R.; DelGrosso, S.
2016-12-01
Surface litter decomposition represents the largest annual carbon (C) flux to the atmosphere from terrestrial ecosystems (Esser et al. 1982). Using broad-scale long-term datasets we show that litter decomposition rates are largely predicted by a climate-decomposition index (CDI) at a global scale, and use CDI to estimate patterns in litter decomposition over the 110 years from 1901-2011. There were rapid changes in CDI over the last 30 y of the record amounting to a 4.3% increase globally. Boreal forests (+13.9%), tundra (+12.2%), savannas (+5.3%), and temperate (+2.4%) and tropical (+2.1%) forests all experienced accelerated decomposition. During the same period, most biomes experienced corresponding increases in a primary production index (PPI) estimated from an ensemble of long-term, observation-based productivity indices. The percent increase in PPI was only half that of decomposition globally. Tropical forests and savannas showed no increase in PPI to offset greater decomposition rates. Temperature-limited ecosystems (i.e., tundra, boreal, and temperate forests) showed the greatest differences between CDI and PPI, highlighting potentially large decoupling of C fluxes in these biomes. Precipitation and actual evapotranspiration were the best climate predictors of CDI at a global scale, while PPI varied consistently with actual evapotranspiration. As expected, temperature was the best predictor of PPI across temperature limited ecosystems. Our results show that climate change could be leading to a decoupling of C uptake and losses, potentially resulting in lower C storage in northern latitudes, temperate and tropical forests, and savannas.
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NASA Astrophysics Data System (ADS)
Stoy, P. C.; Katul, G. G.; Juang, J.; Siqueira, M. B.; Novick, K. A.; Essery, R.; Dore, S.; Kolb, T. E.; Montes-Helu, M. C.; Scott, R. L.
2010-12-01
Vegetation is an important control on the surface energy balance and thereby surface temperature. Boreal forests and arctic shrubs are thought to warm the land surface by absorbing more radiation than the vegetation they replace. The surface temperatures of tropical forests tend to be cooler than deforested landscapes due to enhanced evapotranspiration. The effects of reforestation on surface temperature change in the temperate zone is less-certain, but recent modeling efforts suggest forests have a global warming effect. We quantified the mechanisms driving radiometric surface changes following landcover changes using paired ecosystem case studies from the Ameriflux database with energy balance models of varying complexity. Results confirm previous findings that deciduous and coniferous forests in the southeastern U.S. are ca. 1 °C cooler than an adjacent field on an annual basis because aerodynamic/ecophysiological cooling of 2-3 °C outweighs an albedo-related warming of <1 °C. A 50-70% reduction in the aerodynamic resistance to sensible and latent heat exchange in the forests dominated the cooling effect. A grassland ecosystem that succeeded a stand-replacing ponderosa pine fire was ca. 1 °C warmer than unburned stands because a 1.5 °C aerodynamic warming offset a slight surface cooling due to greater albedo and soil heat flux. An ecosystem dominated by mesquite shrub encroachment was nearly 2 °C warmer than a native grassland ecosystem as aerodynamic and albedo-related warming outweighed a small cooling effect due to changes in soil heat flux. The forested ecosystems in these case studies are documented to have higher carbon uptake than the non-forested systems. Results suggest that temperate forests tend to cool the land surface and suggest that previous model-based findings that forests warm the Earth’s surface globally should be reconsidered.Changes to radiometric surface temperature (K) following changes in vegetation using paired ecosystem case studies C4 grassland and shrub ecosystem surface temperatures were adjusted for differences in air temperature across sites.
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Douglas W. MacCleery
1995-01-01
The 1994 wildfires in the U.S. West have highlighted a problem of forest health and fuel buildups that has been increasing for decades. In many Western forest ecosystems, forest biomass per acre has risen substantially since the 1940s and many forests have dense, fire-prone understories. If current trends continue, there will be: 1) increasing risks to National Forest...
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Restoring Forests and Associated Ecosystem Services on Appalachian Coal Surface Mines
NASA Astrophysics Data System (ADS)
Zipper, Carl E.; Burger, James A.; Skousen, Jeffrey G.; Angel, Patrick N.; Barton, Christopher D.; Davis, Victor; Franklin, Jennifer A.
2011-05-01
Surface coal mining in Appalachia has caused extensive replacement of forest with non-forested land cover, much of which is unmanaged and unproductive. Although forested ecosystems are valued by society for both marketable products and ecosystem services, forests have not been restored on most Appalachian mined lands because traditional reclamation practices, encouraged by regulatory policies, created conditions poorly suited for reforestation. Reclamation scientists have studied productive forests growing on older mine sites, established forest vegetation experimentally on recent mines, and identified mine reclamation practices that encourage forest vegetation re-establishment. Based on these findings, they developed a Forestry Reclamation Approach (FRA) that can be employed by coal mining firms to restore forest vegetation. Scientists and mine regulators, working collaboratively, have communicated the FRA to the coal industry and to regulatory enforcement personnel. Today, the FRA is used routinely by many coal mining firms, and thousands of mined hectares have been reclaimed to restore productive mine soils and planted with native forest trees. Reclamation of coal mines using the FRA is expected to restore these lands' capabilities to provide forest-based ecosystem services, such as wood production, atmospheric carbon sequestration, wildlife habitat, watershed protection, and water quality protection to a greater extent than conventional reclamation practices.
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John B. Bradford; Nicholas R. Jensen; Grant M. Domke; Anthony W. D' Amato
2013-01-01
Forested ecosystems contain the majority of the worldâs terrestrial carbon, and forest management has implications for regional and global carbon cycling. Carbon stored in forests changes with stand age and is affected by natural disturbance and timber harvesting. We examined how harvesting and disturbance interact to influence forest carbon stocks over the Superior...
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Robert L. Deal
2008-01-01
A primary mission of the U.S. Department of Agriculture Forest Service is multiple resource management, and one of the emerging themes is forest restoration. The National Silviculture Workshop, a biennial event co-sponsored by the Forest Service, was held May 7-10, 2007, in Ketchikan, Alaska, with the theme of "Integrated Restoration of Forested Ecosystems to...
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Dynamics of novel forests of Castilla elastica in Puerto Rico: from species to ecosystems
Jessica Fonseca da Silva
2015-01-01
Novel forests (NFs)âforests that contain a combination of introduced and native speciesâare a consequence of intense anthropogenic disturbances and the natural resilience of disturbed ecosystems. The extent to which NFs have similar forest function as comparable native secondary forests is a matter of debate in the scientific community. Little is known about the...
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Predictors of Drought Recovery across Forest Ecosystems
NASA Astrophysics Data System (ADS)
Anderegg, W.
2016-12-01
The impacts of climate extremes on terrestrial ecosystems are poorly understood but central for predicting carbon cycle feedbacks to climate change. Coupled climate-carbon cycle models typically assume that vegetation recovery from extreme drought is immediate and complete, which conflicts with basic plant physiological understanding. Here, we discuss what we have learned about forest ecosystem recovery from extreme drought across spatial and temporal scales, drawing on inference from tree rings, eddy covariance data, large scale gross primary productivity products, and ecosystem models. In tree rings, we find pervasive and substantial "legacy effects" of reduced growth and incomplete recovery for 1-4 years after severe drought, and that legacy effects are most prevalent in dry ecosystems, Pinaceae, and species with low hydraulic safety margins. At larger scales, we see relatively rapid recovery of ecosystem fluxes, with strong influences of ecosystem productivity and diversity and longer recovery periods in high latidue forests. In contrast, no or limited legacy effects are simulated in current climate-vegetation models after drought, and we highlight some of the key missing mechanisms in dynamic vegetation models. Our results reveal hysteresis in forest ecosystem carbon cycling and delayed recovery from climate extremes and help advance a predictive understanding of ecosystem recovery.
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Kulakowski, Dominik; Seidl, Rupert; Holeksa, Jan; Kuuluvainen, Timo; Nagel, Thomas A.; Panayotov, Momchil; Svoboda, Miroslav; Thorn, Simon; Vacchiano, Giorgio; Whitlock, Cathy; Wohlgemuth, Thomas; Bebi, Peter
2017-01-01
Mountain forests are among the most important ecosystems in Europe as they support numerous ecological, hydrological, climatic, social, and economic functions. They are unique relatively natural ecosystems consisting of long-lived species in an otherwise densely populated human landscape. Despite this, centuries of intensive forest management in many of these forests have eclipsed evidence of natural processes, especially the role of disturbances in long-term forest dynamics. Recent trends of land abandonment and establishment of protected forests have coincided with a growing interest in managing forests in more natural states. At the same time, the importance of past disturbances highlighted in an emerging body of literature, and recent increasing disturbances due to climate change are challenging long-held views of dynamics in these ecosystems. Here, we synthesize aspects of this Special Issue on the ecology of mountain forest ecosystems in Europe in the context of broader discussions in the field, to present a new perspective on these ecosystems and their natural disturbance regimes. Most mountain forests in Europe, for which long-term data are available, show a strong and long-term effect of not only human land use but also of natural disturbances that vary by orders of magnitude in size and frequency. Although these disturbances may kill many trees, the forests themselves have not been threatened. The relative importance of natural disturbances, land use, and climate change for ecosystem dynamics varies across space and time. Across the continent, changing climate and land use are altering forest cover, forest structure, tree demography, and natural disturbances, including fires, insect outbreaks, avalanches, and wind disturbances. Projected continued increases in forest area and biomass along with continued warming are likely to further promote forest disturbances. Episodic disturbances may foster ecosystem adaptation to the effects of ongoing and future climatic change. Increasing disturbances, along with trends of less intense land use, will promote further increases in coarse woody debris, with cascading positive effects on biodiversity, edaphic conditions, biogeochemical cycles, and increased heterogeneity across a range of spatial scales. Together, this may translate to disturbance-mediated resilience of forest landscapes and increased biodiversity, as long as climate and disturbance regimes remain within the tolerance of relevant species. Understanding ecological variability, even imperfectly, is integral to anticipating vulnerabilities and promoting ecological resilience, especially under growing uncertainty. Allowing some forests to be shaped by natural processes may be congruent with multiple goals of forest management, even in densely settled and developed countries. PMID:28860677
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Ecosystem Services Derived from Headwater Catchments
We used data from the USEPA’s wadeable streams assessment (WSA), US Forest Service’s forest inventory and analysis (FIA), and select USFS experimental forests (EF) to investigate potential ecosystems services derived from headwater catchments. C, N, and P inputs to these catchmen...
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The impact of human-environment interactions on the stability of forest-grassland mosaic ecosystems
Innes, Clinton; Anand, Madhur; Bauch, Chris T.
2013-01-01
Forest-grassland mosaic ecosystems can exhibit alternative stables states, whereby under the same environmental conditions, the ecosystem could equally well reside either in one state or another, depending on the initial conditions. We develop a mathematical model that couples a simplified forest-grassland mosaic model to a dynamic model of opinions about conservation priorities in a population, based on perceptions of ecosystem rarity. Weak human influence increases the region of parameter space where alternative stable states are possible. However, strong human influence precludes bistability, such that forest and grassland either co-exist at a single, stable equilibrium, or their relative abundance oscillates. Moreover, a perturbation can shift the system from a stable state to an oscillatory state. We conclude that human-environment interactions can qualitatively alter the composition of forest-grassland mosaic ecosystems. The human role in such systems should be viewed as dynamic, responsive element rather than as a fixed, unchanging entity. PMID:24048359
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The ten-ecosystem study investigation plan
NASA Technical Reports Server (NTRS)
Kan, E. P.
1976-01-01
With the continental United States divided into ten forest and grassland ecosystems, the Ten Ecosystem Study (TES) is designed to investigate the feasibility and applicability of state-of-the-art automatic data processing remote sensing technology to inventory forest, grassland, and water resources by using Land Satellite data. The study will serve as a prelude to a possible future nationwide remote sensing application to inventory forest and rangeland renewable resources. This plan describes project design and phases, the ten ecosystem, data utilization and output, personnel organization, resource requirements, and schedules and milestones.
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Barrier island forest ecosystem: role of meteorologic nutrient inputs.
Art, H W; Bormann, F H; Voigt, G K; Woodwell, G M
1974-04-05
The Sunken Forest, located on Fire Island, a barrier island in the Atlantic Ocean off Long Island, New York, is an ecosystem in which most of the basic cation input is in the form of salt spray. This meteorologic input is sufficient to compensate for the lack of certain nutrients in the highly weathered sandy soils. In other ecosystems these nutrients are generally supplied by weathering of soil particles. The compensatory effect of meteorologic input allows for primary production rates in the Sunken Forest similar to those of inland temperate forests.
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Judge, Seth W.; Gaudioso, Jacqueline M.; Gorresen, P. Marcos; Camp, Richard J.
2012-01-01
The endemic solitaire, 'Ōma'o (Myadestes obscurus), is common in windward forests of Hawai'i Island, but has been historically extirpated from leeward forests. The last detections of Ōma'o on the leeward side of the island were in woodland habitat on the western flank of Mauna Loa in 1978. 'Ōma'o were detected in woodland habitat in relatively low densities during a 2010 forest bird survey of Hawai'i Volcanoes National Park. The source of the population is unknown. It is probable they originated from a documented but unsurveyed population of Ōma'o in scrub alpine lava. Alternatively, the birds may have persisted undetected for nearly 35 years, or expanded from windward mesic forests on southeast Mauna Loa. There is no evidence 'Ōma'o recolonized the wet mesic forests of leeward Mauna Loa. The 'Ōma'o can occupy diverse native habitats compared to other species in the Hawai'i Myadestes genus, of which most species are now extinct. The connectivity of each population is not understood but we assume there are significant geographic, physiological, and behavioral barriers for scrub alpine and wet mesic forest populations. The expansion of 'Ōma'o to leeward woodlands is encouraging as the species is Hawai'i Island's last native frugivore capable of dispersing small and medium sized seeds of rare angiosperms, and could have an important role in re-establishing ecosystem function.
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Maria K. Janowiak; Anthony W. D' Amato; Christopher W. Swanston; Louis Iverson; Frank R. Thompson; William D. Dijak; Stephen Matthews; Matthew P. Peters; Anantha Prasad; Jacob S. Fraser; Leslie A. Brandt; Patricia Butler-Leopold; Stephen D. Handler; P. Danielle Shannon; Diane Burbank; John Campbell; Charles Cogbill; Matthew J. Duveneck; Marla R. Emery; Nicholas Fisichelli; Jane Foster; Jennifer Hushaw; Laura Kenefic; Amanda Mahaffey; Toni Lyn Morelli; Nicholas J. Reo; Paul G. Schaberg; K. Rogers Simmons; Aaron Weiskittel; Sandy Wilmot; David Hollinger; Erin Lane; Lindsey Rustad; Pamela H. Templer
2018-01-01
Forest ecosystems will face direct and indirect impacts from a changing climate over the 21st century. This assessment evaluates the vulnerability of forest ecosystems across the New England region (Connecticut, Maine, Massachusetts, New Hampshire, northern New York, Rhode Island, and Vermont) under a range of future climates. We synthesized and summarized information...
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John M. Kabrick; Randy G. Jensen; Stephen R. Shifley; David R. Larsen
2002-01-01
The Missouri Ozark Forest Ecosystem Project (MOFEP) experimentally tests forest ecosystem response to (a) even-aged management with clearcutting, (b) uneven-aged management with single-tree and group selection, and (c) no-harvesting. The nine MOFEP experimental sites in the southeast Missouri Ozarks are small landscapes ranging from 772 ac (312 ha) to 1,271 ac (514 ha...
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Ecosystem heterogeneity determines the ecological resilience of the Amazon to climate change.
Levine, Naomi M; Zhang, Ke; Longo, Marcos; Baccini, Alessandro; Phillips, Oliver L; Lewis, Simon L; Alvarez-Dávila, Esteban; Segalin de Andrade, Ana Cristina; Brienen, Roel J W; Erwin, Terry L; Feldpausch, Ted R; Monteagudo Mendoza, Abel Lorenzo; Nuñez Vargas, Percy; Prieto, Adriana; Silva-Espejo, Javier Eduardo; Malhi, Yadvinder; Moorcroft, Paul R
2016-01-19
Amazon forests, which store ∼ 50% of tropical forest carbon and play a vital role in global water, energy, and carbon cycling, are predicted to experience both longer and more intense dry seasons by the end of the 21st century. However, the climate sensitivity of this ecosystem remains uncertain: several studies have predicted large-scale die-back of the Amazon, whereas several more recent studies predict that the biome will remain largely intact. Combining remote-sensing and ground-based observations with a size- and age-structured terrestrial ecosystem model, we explore the sensitivity and ecological resilience of these forests to changes in climate. We demonstrate that water stress operating at the scale of individual plants, combined with spatial variation in soil texture, explains observed patterns of variation in ecosystem biomass, composition, and dynamics across the region, and strongly influences the ecosystem's resilience to changes in dry season length. Specifically, our analysis suggests that in contrast to existing predictions of either stability or catastrophic biomass loss, the Amazon forest's response to a drying regional climate is likely to be an immediate, graded, heterogeneous transition from high-biomass moist forests to transitional dry forests and woody savannah-like states. Fire, logging, and other anthropogenic disturbances may, however, exacerbate these climate change-induced ecosystem transitions.
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From the litter up and the sky down: Perspectives on urban ...
The structure of the urban forest represents the complex product of local biophysical conditions, socio-economic milieu, people preferences and management with rare counterparts in rural forests. However, urban forest structure, as similarly observed in rural forests, affects key ecological and hydrological processes as well as the plethora of organisms regulating these processes. This seminar talk will firstly present key mechanisms regulating urban eco-hydrological processes “from a litter up” perspective. In particular, fine scale effects of urban forest structure upon i) organic matter decomposition, and comminution, ii) community-assembly of decomposers, detritivores, and ecosystem engineers (i.e. bacteria, litter-dwelling macrofauna, ants), and iii) stormwater runoff infiltration and interception will be discussed. The second part of this intervention will look at the structure of the urban forest “from a sky down” perspective. Recent findings from large scale LiDAR investigations will be presented to discuss social and biophysical drivers affecting urban forest structure at sub-continental scale, as well as short-term tree loss dynamics across residential landscapes, and how these can potentially affect eco-hydrological processes at large scale. Urban forest structure, as similarly observed in rural forests, affects key ecological and hydrological processes as well as the plethora of organisms regulating these processes.
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NITROGEN LOSS FROM SMALL WATERSHEDS IN THE OREGON CASCADES: A STUDY OF FOREST SUCCESSION INFLUENCE
Traditional biogeochemical theory suggests that biotic N limitation (N demand by plants and soil microorganisms) controls ecosystem nitrogen (N) losses, and that stream N export should increase with successional age. I am examining patterns of inorganic and organic N export from...
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Richard Everett; Paul Hessburg; Mark Jensen; Bernard Bormann
1994-01-01
This report responds to the request by Speaker Foley and Senator Hatfield for a scientific evaluation of the effects of Forest Service management practices on the sustainability of eastern Oregon and Washington ecosystems. The report recommends analysis methods and management practices that can be used to build an experimental approach to the restoration of stressed...
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M Martins, Gustavo; Hipólito, Cláudia; Parreira, Filipe; C L Prestes, Afonso; Dionísio, Maria A; N Azevedo, José M; Neto, Ana I
2016-05-01
In many coastal regions, vegetated habitats (e.g. kelps forests, seagrass beds) play a key role in the structure and functioning of shallow subtidal reef ecosystems, by modifying local environmental conditions and by providing food and habitat for a wide range of organisms. In some regions of the world, however, such idiosyncratic ecosystems are largely absent and are often replaced by less notable ecosystem formers. In the present study, we empirically compared the structure and functioning of two distinct shallow-water habitats present in the Azores: one dominated by smaller frondose brown macroalgae (Dictyotaceae and Halopteris) and one dominated by low-lying turfs. Two replicated areas of each habitat were sampled at two different times of the year, to assess spatial and temporal consistency of results. Habitats dominated by small fronds were significantly (ca. 3 times) more productive (when standardized per algal mass) compared to the turf-dominated habitats, and supported a distinct assemblage (both in terms of composition and abundance) of associated macrofauna. Unlike other well-known and studied vegetated habitats (i.e. kelp forests), however, no effects of habitat were found on the structure of benthonic fish assemblages. Results were spatially and temporally consistent suggesting that, in warmer temperate oceans, habitats dominated by species of smaller frondose brown algae can also play an important role in the structure and functioning of subtidal communities and may, to a certain extent, be considered analogous to other well-known vegetated habitats around the world (i.e. kelp forests, seagrass beds). Copyright © 2016 Elsevier Ltd. All rights reserved.
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Aquatic biodiversity in forests: a weak link in ecosystem services resilience
Brooke E. Penaluna; Deanna H. Olson; Rebecca L. Flitcroft; Matthew A. Weber; J. Ryan Bellmore; Steven M. Wondzell; Jason B. Dunham; Sherri L. Johnson; Gordon H. Reeves
2017-01-01
The diversity of aquatic ecosystems is being quickly reduced on many continents, warranting a closer examination of the consequences for ecological integrity and ecosystem services. Here we describe intermediate and final ecosystem services derived from aquatic biodiversity in forests. We include a summary of the factors framing the assembly of aquatic biodiversity in...
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Responses of photosynthetic parameters to drought in subtropical forest ecosystem of China
Zhou, Lei; Wang, Shaoqiang; Chi, Yonggang; Li, Qingkang; Huang, Kun; Yu, Quanzhou
2015-01-01
The mechanism underlying the effect of drought on the photosynthetic traits of leaves in forest ecosystems in subtropical regions is unclear. In this study, three limiting processes (stomatal, mesophyll and biochemical limitations) that control the photosynthetic capacity and three resource use efficiencies (intrinsic water use efficiency (iWUE), nitrogen use efficiency (NUE) and light use efficiency (LUE)), which were characterized as the interactions between photosynthesis and environmental resources, were estimated in two species (Schima superba and Pinus massoniana) under drought conditions. A quantitative limitation analysis demonstrated that the drought-induced limitation of photosynthesis in Schima superba was primarily due to stomatal limitation, whereas for Pinus massoniana, both stomatal and non-stomatal limitations generally exhibited similar magnitudes. Although the mesophyll limitation represented only 1% of the total limitation in Schima superba, it accounted for 24% of the total limitations for Pinus massoniana. Furthermore, a positive relationship between the LUE and NUE and a marginally negative relationship or trade-off between the NUE and iWUE were observed in the control plots. However, drought disrupted the relationships between the resource use efficiencies. Our findings may have important implications for reducing the uncertainties in model simulations and advancing the understanding of the interactions between ecosystem functions and climate change. PMID:26666469
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Responses of photosynthetic parameters to drought in subtropical forest ecosystem of China
NASA Astrophysics Data System (ADS)
Zhou, Lei; Wang, Shaoqiang; Chi, Yonggang; Li, Qingkang; Huang, Kun; Yu, Quanzhou
2015-12-01
The mechanism underlying the effect of drought on the photosynthetic traits of leaves in forest ecosystems in subtropical regions is unclear. In this study, three limiting processes (stomatal, mesophyll and biochemical limitations) that control the photosynthetic capacity and three resource use efficiencies (intrinsic water use efficiency (iWUE), nitrogen use efficiency (NUE) and light use efficiency (LUE)), which were characterized as the interactions between photosynthesis and environmental resources, were estimated in two species (Schima superba and Pinus massoniana) under drought conditions. A quantitative limitation analysis demonstrated that the drought-induced limitation of photosynthesis in Schima superba was primarily due to stomatal limitation, whereas for Pinus massoniana, both stomatal and non-stomatal limitations generally exhibited similar magnitudes. Although the mesophyll limitation represented only 1% of the total limitation in Schima superba, it accounted for 24% of the total limitations for Pinus massoniana. Furthermore, a positive relationship between the LUE and NUE and a marginally negative relationship or trade-off between the NUE and iWUE were observed in the control plots. However, drought disrupted the relationships between the resource use efficiencies. Our findings may have important implications for reducing the uncertainties in model simulations and advancing the understanding of the interactions between ecosystem functions and climate change.
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NASA Astrophysics Data System (ADS)
Drohan, Patrick; Brittingham, Margaret; Mortensen, David; Barlow, Kathryn; Langlois, Lillie
2017-04-01
Worldwide unconventional shale-gas development has the potential to cause substantial landscape disturbance. The northeastern U.S.A. Appalachian Mountains across the states of Pennsylvania, West Virginia, Ohio, and Kentucky, are experiencing rapid landscape change as unconventional gas development occurs. We highlight several years of our research from this region in order to demonstrate the unique effect unconventional development has had on forested ecosystems. Infrastructure development has had a wide-reaching and varied effect on forested ecosystems and their services, which has resulted in temporary disturbances and long-lasting ones altering habitats and their viability. Corridor disturbances, such as pipelines, are the most spatially extensive disturbance and have substantially fragmented forest cover. Core forest disturbance, especially, in upper watershed positions, has resulted in disproportionate disturbances to forested ecosystems and their wildlife, and suggests a need for adaptive land management strategies to minimize and mitigate the effects of gas development. Soil and water resources are most affected by surface disturbances; however, soil protection and restoration strategies are evolving as the gas play changes economically. Dynamic soil properties related to soil organic matter and water availability respond uniquely to unconventional gas development and new, flexible restoration strategies are required to support long-term ecosystem stability. While the focus of management and research to date has been on acute disturbances to forested ecosystems, unconventional gas development is clearly a greater chronic, long-term disturbance factor in the Appalachian Mountains. Effectively managing ecosystems where unconventional gas development is occurring is a complicated interplay between public, private and corporate interests.
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Abdalla, Mohamed; Saunders, Matthew; Hastings, Astley; Williams, Mike; Smith, Pete; Osborne, Bruce; Lanigan, Gary; Jones, Mike B
2013-11-01
In this study, we compared measured and simulated Net Ecosystem Exchange (NEE) values from three wide spread ecosystems in the southeast of Ireland (forest, arable and grassland), and investigated the suitability of the DNDC (the DeNitrification-DeComposition) model to estimate present and future NEE. Although, the field-DNDC version overestimated NEE at temperatures >5 °C, forest-DNDC under-estimated NEE at temperatures >5 °C. The results suggest that the field/forest DNDC models can successfully estimate changes in seasonal and annual NEE from these ecosystems. Differences in NEE were found to be primarily land cover specific. The annual NEE was similar for the grassland and arable sites, but due to the contribution of exported carbon, the soil carbon increased at the grassland site and decreased at the arable site. The NEE of the forest site was an order of magnitude larger than that of the grassland or arable ecosystems, with large amounts of carbon stored in woody biomass and the soil. The average annual NEE, GPP and Reco values over the measurement period were -904, 2379 and 1475 g C m(-2) (forest plantations), -189, 906 and 715 g C m(-2) (arable systems) and -212, 1653 and 1444 g C m(-2) (grasslands), respectively. The average RMSE values were 3.8 g C m(-2) (forest plantations), 0.12 g C m(-2) (arable systems) and 0.21 g C m(-2) (grasslands). When these models were run with climate change scenarios to 2060, predictions show that all three ecosystems will continue to operate as carbon sinks. Further, climate change may decrease the carbon sink strength in the forest plantations by up to 50%. This study supports the use of the DNDC model as a valid tool to predict the consequences of climate change on NEE from different ecosystems. Copyright © 2012 Elsevier B.V. All rights reserved.
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NASA Astrophysics Data System (ADS)
SATO, H.; Iwahana, G.; Ohta, T.
2013-12-01
Siberian larch forest is the largest coniferous forest region in the world. In this vast region, larch often forms nearly pure stands, regenerated by recurrent fire. This region is characterized by a short and dry growing season; the annual mean precipitation for Yakutsk was only about 240 mm. To maintain forest ecosystem under such small precipitation, underlying permafrost and seasonal soil freezing-thawing-cycle have been supposed to play important roles; (1) frozen ground inhibits percolation of soil water into deep soil layers, and (2) excess soil water at the end of growing season can be carried over until the next growing season as ice, and larch trees can use the melt water. As a proof for this explanation, geographical distribution of Siberian larch region highly coincides with continuous and discontinuous permafrost zone. Recent observations and simulation studies suggests that existences of larch forest and permafrost in subsurface layer are co-dependent; permafrost maintains the larch forest by enhancing water use efficiency of trees, while larch forest maintains permafrost by inhibiting solar radiation and preventing heat exchanges between soil and atmosphere. Owing to such complexity and absence of enough ecosystem data available, current-generation Earth System Models significantly diverse in their prediction of structure and key ecosystem functions in Siberian larch forest under changing climate. Such uncertainty should in turn expand uncertainty over predictions of climate, because Siberian larch forest should have major role in the global carbon balance with its huge area and vast potential carbon pool within the biomass and soil, and changes in boreal forest albedo can have a considerable effect on Northern Hemisphere climate. In this study, we developed an integrated ecosystem model, which treats interactions between plant-dynamics and freeze-thaw cycles. This integrated model contains a dynamic global vegetation model SEIB-DGVM, which simulates plant and carbon dynamics. It also contains a one-dimensional land surface model NOAH 2.7.1, which simulates soil moisture (both liquid and frozen), soil temperature, snowpack depth and density, canopy water content, and the energy and water fluxes. This integrated model quantitatively reconstructs post-fire development of forest structure (i.e. LAI and biomass) and organic soil layer, which dampens heat exchanges between soil and atmosphere. With the post-fire development of LAI and the soil organic layer, the integrated model also quantitatively reconstructs changes in seasonal maximum of active layer depth. The integrated model is then driven by the IPCC A1B scenario of rising atmospheric CO2, and by climate changes during the twenty-first century resulting from the change in CO2. This simulation suggests that forecasted global warming would causes decay of Siberian larch ecosystem, but such responses could be delayed by "memory effect" of the soil organic layer for hundreds of years.
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Fire, competition and forest pests: landscape treatment to sustain ecosystem function
Geral I. McDonald; A. E. Harvey; J. R. Tonn
2000-01-01
Fire, competition for light and water, and native forest pests have interacted for millennia in western forests to produce a countryside dominated by seral species of conifers. These conifer-dominated ecosystems exist in six kinds of biotic communities. We divided one of these communities, the Rocky Mountain Montane Conifer Forest, into 31 subseries based on the...
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Z.L. Walton; N.C. Poudyal; J. Hepinstall; C. Johnson Gaither; B.B. Boley
2015-01-01
While the growing literature on forest ecosystem services has examined the value and significance of a range ofservices, our understanding of the health-related benefits of ecosystem services from forests is still limited. Tocharacterize the role of forest resources in reducing community vulnerability to the heat effects of climate...
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Contingent Valuation of Forest Ecosystem Protection
Randall A. Kramer; Thomas P. Holmes; Michelle Haefele
2003-01-01
In recent decades, concerns have arisen about the proper valuation of the world's forests. While some of these concerns have to do with market distortions for timber products or inadequate data on non-timber forest products, an additional challenge is to uncover the economic worth of non- market services provided by forest ecosystems (Kramer et al. 1997). This has...
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The legacy and continuity of forest disturbance, succession, and species at the MOFEP sites
Richard Guyette; John M. Kabrick
2002-01-01
Information about the scale, frequency, and legacy of disturbance regimes and their relation to the distribution of forest species is sparse in Ozark ecosystems. Knowledge of these relationships is valuable for understanding present-day forest ecosystem species composition and structure and for predicting how Missouri's forests will respond to management. Here, we...
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G. Scott Haulton
2013-01-01
Disturbance plays an important role in forest development processes. Present-day forest condition can be viewed as the cumulative result of various historical disturbance events; therefore, an understanding of disturbance history is important when describing overall forest condition. Pre-treatment studies of the Hardwood Ecosystem Experiment (HEE) have described...
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Linda A. Joyce; Geoffry M. Blate; Jeremy S. Littell; Steven G. McNulty; Constance I. Millar; Susanne C. Moser; Ronald P. Neilson; Kathy O' Halloran; David L. Peterson
2008-01-01
The National Forest System (NFS) is composed of 155 national forests (NFs) and 20 national grasslands (NGs), which encompass a wide range of ecosystems, harbor much of the nationâs biodiversity, and provide myriad goods and services. The mission of the U.S. Forest Service (USFS), which manages the NFS, has broadened from water and timber to sustaining ecosystem health...
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The maintenance of key biodiversity attributes through ecosystem restoration operations
Robert W. Gray; Bruce A. Blackwell
2008-01-01
The requirement to manage for key biodiversity attributes in dry forest ecosystems is mandated in the Forest Practices Code Act of British Columbia. These attributes include snags, large old trees, and large organic debris. In the Squamish Forest District dry forest restoration activities center on the use of thinning operations followed by prescribed fire to restore...
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Initial responses of forest understories to varying levels and patterns of green-tree retention.
Charles B. Halpern; Donald McKenzie; Shelley A. Evans; Douglas A. Maguire
2005-01-01
Timber harvest with "green-tree" retention has been adopted in many temperate and boreal forest ecosystems, reflecting growing appreciation for the ecological values of managed forests. On federal forest lands in the Pacific Northwest, standards and guidelines for green-tree retention have been adopted, but systematic assessments of ecosystem response have...
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Integrating neotropical migratory birds into Forest Service plans for ecosystem management
Deborah M. Finch; William M. Block; Reg A. Fletcher; Leon F. Fager
1993-01-01
The USDA Forest Service is undergoing a major change in focus in response to public interests, growing concern for sustaining natural resources, and new knowledge about wildlife, fisheries, forests and grasslands, and how they interact at the ecosystem level. This shift in direction affects how Forest Service lands are managed, what research is conducted, how resource...
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Integrating studies in the Missouri Ozark Forest Ecosystem Project: Status and outlook
David Gwaze; Stephen Sheriff; John Kabrick; Larry Vangilder
2011-01-01
The Missouri Ozark Forest Ecosystem Project (MOFEP), which was started in 1989 by the Missouri Department of Conservation, evaluates the effects of forest management practices (even-aged management, uneven-aged management, and no-harvest management) on upland oak-forest components in southern Missouri. MOFEP is a long-term, landscape-level, fully replicated, and...
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Adapting to climate change in United States national forests
G. M. Blate; L. A. Joyce; J. S. Littell; S. G. McNulty; C. I. Millar; S. C. Moser; R. P. Neilson; K. O’Halloran; D. L. Peterson
2009-01-01
Climate change is already affecting forests and other ecosystems, and additional, potentially more severe impacts are expected (IPCC, 2007; CCSP, 2008a, 2008b). As a result, forest managers are seeking practical guidance on how to adapt their current practices and, if necessary, their goals. Adaptations of forest ecosystems, which in this context refer to adjustments...
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R. K. Kolka; C. C. Trettin; E. A. Nelson; C. D. Barton; D. E. Fletcher
2002-01-01
Forested wetland restoration assessment is difficult because of the timeframe necessary for the development of a forest ecosystem. The development of a forested wetland ecosystem includes the recovery of hydrology, soils, vegetation, and faunal communities. To assess forested wetland restoration projects, measures need to be developed that are sensitive to early...
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R.K. Kolka; Carl C. Trettin; E.A. Nelson; C.D. Barton; D.E. Fletcher
2002-01-01
Forested wetland restoration assessment is difficult because of the timeframe necessary for the development of a forest ecosystem. The development of a forested wetland ecosystem includes the recovery of hydrology, soils, vegetation, and faunal communities. To assess forested wetland restoration projects, measures need to be developed that are sensitive to early...
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USDA-ARS?s Scientific Manuscript database
Forest ecosystems in the southern United States are dramatically altered by three major 26 disturbances: timber harvesting, hurricane, and permanent land conversion. Understanding and quantifying effects of disturbance on forest carbon, nitrogen, and water cycles is critical for sustainable forest m...
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The role of remote sensing in process‐scaling studies of managed forest ecosystems
Jeffrey G. Masek; Daniel J. Hayes; M. Joseph Hughes; Sean P. Healey; David P. Turner
2015-01-01
Sustaining forest resources requires a better understanding of forest ecosystem processes, and how management decisions and climate change may affect these processes in the future. While plot and inventory data provide our most detailed information on forest carbon, energy, and water cycling, applying this understanding to broader spatial and temporal domains...
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Paul G. Schaberg; Donald H. DeHayes; Gary J. Hawley; Samuel E. Nijensohn
2008-01-01
Healthy forests provide many of the essential ecosystem services upon which all life depends. Genetic diversity is an essential component of long-term forest health because it provides a basis for adaptation and resilience to environmental stress and change. In addition to natural processes, numerous anthropogenic factors deplete forest genetic resources. Genetic...
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The experimental design of the Missouri Ozark Forest Ecosystem Project
Steven L. Sheriff; Shuoqiong He
1997-01-01
The Missouri Ozark Forest Ecosystem Project (MOFEP) is an experiment that examines the effects of three forest management practices on the forest community. MOFEP is designed as a randomized complete block design using nine sites divided into three blocks. Treatments of uneven-aged, even-aged, and no-harvest management were randomly assigned to sites within each block...
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Lara, Mark J; Genet, Hélène; McGuire, Anthony D; Euskirchen, Eugénie S; Zhang, Yujin; Brown, Dana R N; Jorgenson, Mark T; Romanovsky, Vladimir; Breen, Amy; Bolton, William R
2016-02-01
Lowland boreal forest ecosystems in Alaska are dominated by wetlands comprised of a complex mosaic of fens, collapse-scar bogs, low shrub/scrub, and forests growing on elevated ice-rich permafrost soils. Thermokarst has affected the lowlands of the Tanana Flats in central Alaska for centuries, as thawing permafrost collapses forests that transition to wetlands. Located within the discontinuous permafrost zone, this region has significantly warmed over the past half-century, and much of these carbon-rich permafrost soils are now within ~0.5 °C of thawing. Increased permafrost thaw in lowland boreal forests in response to warming may have consequences for the climate system. This study evaluates the trajectories and potential drivers of 60 years of forest change in a landscape subjected to permafrost thaw in unburned dominant forest types (paper birch and black spruce) associated with location on elevated permafrost plateau and across multiple time periods (1949, 1978, 1986, 1998, and 2009) using historical and contemporary aerial and satellite images for change detection. We developed (i) a deterministic statistical model to evaluate the potential climatic controls on forest change using gradient boosting and regression tree analysis, and (ii) a 30 × 30 m land cover map of the Tanana Flats to estimate the potential landscape-level losses of forest area due to thermokarst from 1949 to 2009. Over the 60-year period, we observed a nonlinear loss of birch forests and a relatively continuous gain of spruce forest associated with thermokarst and forest succession, while gradient boosting/regression tree models identify precipitation and forest fragmentation as the primary factors controlling birch and spruce forest change, respectively. Between 1950 and 2009, landscape-level analysis estimates a transition of ~15 km² or ~7% of birch forests to wetlands, where the greatest change followed warm periods. This work highlights that the vulnerability and resilience of lowland ice-rich permafrost ecosystems to climate changes depend on forest type. © 2015 John Wiley & Sons Ltd.
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Lara, M.; Genet, Helene; McGuire, A. David; Euskirchen, Eugénie S.; Zhang, Yujin; Brown, Dana R. N.; Jorgenson, M.T.; Romanovsky, V.; Breen, Amy L.; Bolton, W.R.
2016-01-01
Lowland boreal forest ecosystems in Alaska are dominated by wetlands comprised of a complex mosaic of fens, collapse-scar bogs, low shrub/scrub, and forests growing on elevated ice-rich permafrost soils. Thermokarst has affected the lowlands of the Tanana Flats in central Alaska for centuries, as thawing permafrost collapses forests that transition to wetlands. Located within the discontinuous permafrost zone, this region has significantly warmed over the past half-century, and much of these carbon-rich permafrost soils are now within ~0.5 °C of thawing. Increased permafrost thaw in lowland boreal forests in response to warming may have consequences for the climate system. This study evaluates the trajectories and potential drivers of 60 years of forest change in a landscape subjected to permafrost thaw in unburned dominant forest types (paper birch and black spruce) associated with location on elevated permafrost plateau and across multiple time periods (1949, 1978, 1986, 1998, and 2009) using historical and contemporary aerial and satellite images for change detection. We developed (i) a deterministic statistical model to evaluate the potential climatic controls on forest change using gradient boosting and regression tree analysis, and (ii) a 30 × 30 m land cover map of the Tanana Flats to estimate the potential landscape-level losses of forest area due to thermokarst from 1949 to 2009. Over the 60-year period, we observed a nonlinear loss of birch forests and a relatively continuous gain of spruce forest associated with thermokarst and forest succession, while gradient boosting/regression tree models identify precipitation and forest fragmentation as the primary factors controlling birch and spruce forest change, respectively. Between 1950 and 2009, landscape-level analysis estimates a transition of ~15 km² or ~7% of birch forests to wetlands, where the greatest change followed warm periods. This work highlights that the vulnerability and resilience of lowland ice-rich permafrost ecosystems to climate changes depend on forest type.
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Coherence between woody carbon uptake and net ecosystem productivity at five eddy-covariance sites
NASA Astrophysics Data System (ADS)
Babst, F.; Bouriaud, O.; Papale, D.; Gielen, B.; Janssens, I.; Nikinmaa, E.; Ibrom, A.; Wu, J.; Bernhofer, C.; Koestner, B.; Gruenwald, T.; Seufert, G.; Ciais, P.; Frank, D. C.
2013-12-01
Forest growth ranks amongst the most important processes that determine the carbon balance of terrestrial ecosystems. Quantifications of forest carbon cycling can be made e.g. using biometric and eddy-covariance (EC) techniques. Both offer different perspectives on carbon uptake and attempts to combine them have been inconsistent and variably successful in the past. This contributes to persistent uncertainties regarding carbon allocation in forest ecosystems and complicates precise vegetation model parameterization. Aiming to reconcile assessments of carbon cycling from biometric and EC techniques, we measured radial tree growth and wood density at five long-term EC stations across Europe. The resulting records were used to calculate annual carbon uptake during above-ground wood formation and compared to monthly and seasonal CO2-flux measurements. Efforts were made to identify i) the time periods when EC and tree-ring data correspond best in different parts of Europe and ii) the fraction of eddy-fluxes which is associated with changes in above-ground woody carbon stocks. Biometric measurements and net ecosystem productivity (NEP) proved largely compatible at seasonal time scales while relationships with gross primary productivity (GPP) were often weaker. Results suggest a partitioning of sequestered carbon mainly used for volume increase (January-June) and a combination of cell-wall thickening and storage (July-September). The inter-annual variability in above-ground woody carbon uptake was significantly linked with absolute productivity ranging between 69-366 g C m-2 y-1 at boreal and temperate sites, thereby accounting for 10-25% of GPP, 15-32% of TER, and 25-80% of NEP. These findings from sites representing the major European climate zones and tree species contribute to improved quantification of above-ground carbon allocation in forests. Furthermore, they refine knowledge on processes driving ecosystem productivity important for e.g. vegetation models and provide an enhanced framework for integrative studies linking tree-ring parameters with EC measurements.
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Koarashi, Jun; Atarashi-Andoh, Mariko; Matsunaga, Takeshi; Sanada, Yukihisa
2016-01-01
The Fukushima Daiichi nuclear power plant disaster caused serious radiocesium (137Cs) contamination of forest ecosystems over a wide area. Forest-floor organic layers play a key role in controlling the overall bioavailability of 137Cs in forest ecosystems; however, there is still an insufficient understanding of how forest types influence the retention capability of 137Cs in organic layers in Japanese forest ecosystems. Here we conducted plot-scale investigations on the retention of 137Cs in organic layers at two contrasting forest sites in Fukushima. In a deciduous broad-leaved forest, approximately 80% of the deposited 137Cs migrated to mineral soil located below the organic layers within two years after the accident, with an ecological half-life of approximately one year. Conversely, in an evergreen coniferous forest, more than half of the deposited 137Cs remained in the organic layers, with an ecological half-life of 2.1 years. The observed retention behavior can be well explained by the tree phenology and accumulation of 137Cs associated with litter materials with different degrees of degradation in the organic layers. Spatial and temporal patterns of gamma-ray dose rates depended on the retention capability. Our results demonstrate that enhanced radiation risks last longer in evergreen coniferous forests than in deciduous broad-leaved forests. PMID:27974832
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NASA Astrophysics Data System (ADS)
Koarashi, Jun; Atarashi-Andoh, Mariko; Matsunaga, Takeshi; Sanada, Yukihisa
2016-12-01
The Fukushima Daiichi nuclear power plant disaster caused serious radiocesium (137Cs) contamination of forest ecosystems over a wide area. Forest-floor organic layers play a key role in controlling the overall bioavailability of 137Cs in forest ecosystems; however, there is still an insufficient understanding of how forest types influence the retention capability of 137Cs in organic layers in Japanese forest ecosystems. Here we conducted plot-scale investigations on the retention of 137Cs in organic layers at two contrasting forest sites in Fukushima. In a deciduous broad-leaved forest, approximately 80% of the deposited 137Cs migrated to mineral soil located below the organic layers within two years after the accident, with an ecological half-life of approximately one year. Conversely, in an evergreen coniferous forest, more than half of the deposited 137Cs remained in the organic layers, with an ecological half-life of 2.1 years. The observed retention behavior can be well explained by the tree phenology and accumulation of 137Cs associated with litter materials with different degrees of degradation in the organic layers. Spatial and temporal patterns of gamma-ray dose rates depended on the retention capability. Our results demonstrate that enhanced radiation risks last longer in evergreen coniferous forests than in deciduous broad-leaved forests.
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Management Impacts on Carbon Dynamics in a Sierra Nevada Mixed Conifer Forest
Dore, Sabina; Fry, Danny L.; Collins, Brandon M.; Vargas, Rodrigo; York, Robert A.; Stephens, Scott L.
2016-01-01
Forest ecosystems can act as sinks of carbon and thus mitigate anthropogenic carbon emissions. When forests are actively managed, treatments can alter forests carbon dynamics, reducing their sink strength and switching them from sinks to sources of carbon. These effects are generally characterized by fast temporal dynamics. Hence this study monitored for over a decade the impacts of management practices commonly used to reduce fire hazards on the carbon dynamics of mixed-conifer forests in the Sierra Nevada, California, USA. Soil CO2 efflux, carbon pools (i.e. soil carbon, litter, fine roots, tree biomass), and radial tree growth were compared among un-manipulated controls, prescribed fire, thinning, thinning followed by fire, and two clear-cut harvested sites. Soil CO2 efflux was reduced by both fire and harvesting (ca. 15%). Soil carbon content (upper 15 cm) was not significantly changed by harvest or fire treatments. Fine root biomass was reduced by clear-cut harvest (60–70%) but not by fire, and the litter layer was reduced 80% by clear-cut harvest and 40% by fire. Thinning effects on tree growth and biomass were concentrated in the first year after treatments, whereas fire effects persisted over the seven-year post-treatment period. Over this period, tree radial growth was increased (25%) by thinning and reduced (12%) by fire. After seven years, tree biomass returned to pre-treatment levels in both fire and thinning treatments; however, biomass and productivity decreased 30%-40% compared to controls when thinning was combined with fire. The clear-cut treatment had the strongest impact, reducing ecosystem carbon stocks and delaying the capacity for carbon uptake. We conclude that post-treatment carbon dynamics and ecosystem recovery time varied with intensity and type of treatments. Consequently, management practices can be selected to minimize ecosystem carbon losses while increasing future carbon uptake, resilience to high severity fire, and climate related stresses. PMID:26918460
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NASA Astrophysics Data System (ADS)
Osenga, E. C.; Cundiff, J.; Arnott, J. C.; Katzenberger, J.; Taylor, J. R.; Jack-Scott, E.
2015-12-01
An interactive tool called the Forest Health Index (FHI) has been developed for the Roaring Fork watershed of Colorado, with the purpose of improving public understanding of local forest management and ecosystem dynamics. The watershed contains large areas of White River National Forest, which plays a significant role in the local economy, particularly for recreation and tourism. Local interest in healthy forests is therefore strong, but public understanding of forest ecosystems is often simplified. This can pose challenges for land managers and researchers seeking a scientifically informed approach to forest restoration, management, and planning. Now in its second iteration, the FHI is a tool designed to help bridge that gap. The FHI uses a suite of indicators to create a numeric rating of forest functionality and change, based on the desired forest state in relation to four categories: Ecological Integrity, Public Health and Safety, Ecosystem Services, and Sustainable Use and Management. The rating is based on data derived from several sources including local weather stations, stream gauge data, SNOTEL sites, and National Forest Service archives. In addition to offering local outreach and education, this project offers broader insight into effective communication methods, as well as into the challenges of using quantitative analysis to rate ecosystem health. Goals of the FHI include its use in schools as a means of using local data and place-based learning to teach basic math and science concepts, improved public understanding of ecological complexity and need for ongoing forest management, and, in the future, its use as a model for outreach tools in other forested communities in the Intermountain West.
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Forest Service R&D — Invasive Insects: Visions for the Future
Kier D. Klepzig; Therese M. Poland; Nancy E. Gillette; Robert A. Haack; Melody A. Keena; Daniel R. Miller; Michael E. Montgomery; Steven J. Seybold; Patrick C. Tobin
2009-01-01
The Forest Service has identified invasive species as one of four significant threats to our Nationâs forest and rangeland ecosystems and likened the problem to a âcatastrophic wildfire in slow motion.â Forest Service Research and Development (R&D) has a crucial role in providing insight and options to protect trees, forests, and ecosystems from the threat of...
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Victor A. Rudis; John B. Tansey
1991-01-01
Information from plots surveyed by U.S.D.A., Forest Service, Forest Inventory and Analysis (FIA) units provides a basis for classifying human-dominated ecosystems at the regional scale of resolution.Attributes include forest stand measures, evidence of human influence, and other disturbances.Data from recent FIA surveys suggest that human influences are common to...
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2018-01-01
Climate change has been identified as the primary threat to the integrity and functioning of ecosystems in this century, although there is still much uncertainty about its effects and the degree of vulnerability for different ecosystems to this threat. Here we propose a new methodological approach capable of measuring and mapping the resilience of terrestrial ecosystems at large scales based on their climatic niche. To do this, we used high spatial resolution remote sensing data and ecological niche modeling techniques to calculate and spatialize the resilience of three stable states of ecosystems in South America: forest, savanna, and grassland. Also, we evaluated the sensitivity of ecosystems to climate stress, the likelihood of exposure to non-analogous climatic conditions, and their respective adaptive capacities in the face of climate change. Our results indicate that forests, the most productive and biodiverse terrestrial ecosystems on the earth, are more vulnerable to climate change than savannas or grasslands. Forests showed less resistance to climate stress and a higher chance of exposure to non-analogous climatic conditions. If this scenario occurs, the forest ecosystems would have less chance of adaptation compared to savannas or grasslands because of their narrow climate niche. Therefore, we can conclude that a possible consolidation of non-analogous climatic conditions would lead to a loss of resilience in the forest ecosystem, significantly increasing the chance of a critical transition event to another stable state with a lower density of vegetation cover (e.g., savanna or grassland). PMID:29554132
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Chen, Xiao-feng; Jiang, Hong; Niu, Xiao-dong; Zhang, Jin-meng; Liu, Yu-li; Fang, Cheng-yuan
2016-02-01
The carbon flux of subtropical bamboo forest ecosystem was continuously measured using eddy covariance technique in Anji County of Zhejiang Province, China. The monthly net ecosystem productivity (NEP), ecosystem respiration (Re) and gross ecosystem productivity (GEP) data from 2011 to 2013 were selected to analyze the impacts of seasonal high temperature and drought on the carbon flux of bamboo forest ecosystem. The results showed that there were big differences among annual NEP of bamboo forest from 2011 to 2013. Because of the asynchronization of precipitation and heat, the seasonal high temperature and drought in July and August of 2013 caused significant decline in NEP by 59.9% and 80.0% when compared with the same months in 2011. Correlation analysis of the NEP, Re, GEP and environmental factors suggested that the atmosphere temperatures were significantly correlated with Re and GEP in 2011 and 2013 (P<0.05). However, to air and soil moisture, Re and GEP had different responses, that was, GEP was more vulnerable by the decrease of the soil moisture compared with Re. Besides, the raising of saturation vapour pressure promoted the Re modestly but inhibited the GEP, which was supposed to be the main reason for NEP decrease of bamboo forest ecosystem in Anji, from July to August in 2013.
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2012-01-01
Background Forests of the Midwest U.S. provide numerous ecosystem services. Two of these, carbon sequestration and wood production, are often portrayed as conflicting. Currently, carbon management and biofuel policies are being developed to reduce atmospheric CO2 and national dependence on foreign oil, and increase carbon storage in ecosystems. However, the biological and industrial forest carbon cycles are rarely studied in a whole-system structure. The forest system carbon balance is the difference between the biological (net ecosystem production) and industrial (net emissions from forest industry) forest carbon cycles, but to date this critical whole system analysis is lacking. This study presents a model of the forest system, uses it to compute the carbon balance, and outlines a methodology to maximize future carbon uptake in a managed forest region. Results We used a coupled forest ecosystem process and forest products life cycle inventory model for a regional temperate forest in the Midwestern U.S., and found the net system carbon balance for this 615,000 ha forest was positive (2.29 t C ha-1 yr-1). The industrial carbon budget was typically less than 10% of the biological system annually, and averaged averaged 0.082 t C ha-1 yr-1. Net C uptake over the next 100-years increased by 22% or 0.33 t C ha-1 yr-1 relative to the current harvest rate in the study region under the optized harvest regime. Conclusions The forest’s biological ecosystem current and future carbon uptake capacity is largely determined by forest harvest practices that occurred over a century ago, but we show an optimized harvesting strategy would increase future carbon sequestration, or wood production, by 20-30%, reduce long transportation chain emissions, and maintain many desirable stand structural attributes that are correlated to biodiversity. Our results for this forest region suggest that increasing harvest over the next 100 years increases the strength of the carbon sink, and that carbon sequestration and wood production are not conflicting for this particular forest ecosystem. The optimal harvest strategy found here may not be the same for all forests, but the methodology is applicable anywhere sufficient forest inventory data exist. PMID:22713794
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soil carbon pools within oak forest is endangered by global climate change in central mexico
NASA Astrophysics Data System (ADS)
García-Oliva, Felipe; Merino, Agustín; González-Rodriguez, Antonio; Chávez-Vergara, Bruno; Tapia-Torres, Yunuen; Oyama, Ken
2016-04-01
Forest soil represents the main C pool in terrestrial ecosystems. In particular, temperate forest ecosystems play an important role in the C budget among tropical countries, such as Mexico. For example, the temperate forest ecosystem contains higher C contents on average (295 Mg C ha-1) than the soil C associated with other ecosystems in Mexico (between 56 to 287 Mg C ha-1). At a regional scale, oak forest has the highest C content (460 Mg C ha-1) among the forest ecosystem in Michoacán State at Central Mexico. At the local scale, the soil C content is strongly affected by the composition of organic matter produced by the plant species. The oak species are very diverse in Mexico, distributed within two sections: Quercus sensu stricto and Lobatae. The oak species from Quercus s.s. section produced litterfall with lower concentrations of recalcitrant and thermostable compounds than oak species from Lobatae section, therefore the soil under the former species had higher microbial activity and nutrient availability than the soil under the later species. However, the forest fragment with higher amount of oak species from Quercus s.s. section increases the amount of soil C contents. Unfortunately, Quercus species distribution models for the central western region of Mexico predict a decrease of distribution area of the majority of oak species by the year 2080, as a consequence of higher temperatures and lower precipitation expected under climate change scenarios. Additionally to these scenarios, the remnant oak forest fragments suffer strong degradation due to uncontrolled wood extraction and deforestation. For this reason, the conservation of oak forest fragments is a priority to mitigate the greenhouse gases emission to the atmosphere. In order to enhance the protection of these forest fragments it is required that the society identify the ecosystem services that are provided by these forest fragments.
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DOE Office of Scientific and Technical Information (OSTI.GOV)
Gough, Christopher; Curtis, Peter; Hardiman, Brady
Century-old forests in the U.S. upper Midwest and Northeast power much of North Amer- ica’s terrestrial carbon (C) sink, but these forests’ production and C sequestration capacity are expected to soon decline as fast-growing early successional species die and are replaced by slower growing late successional species. But will this really happen? Here we marshal empirical data and ecological theory to argue that substantial declines in net ecosystem production (NEP) owing to reduced forest growth, or net primary production (NPP), are not imminent in regrown temperate deciduous forests over the next several decades. Forest age and production data for temperatemore » deciduous forests, synthesized from published literature, suggest slight declines in NEP and increasing or stable NPP during middle successional stages. We revisit long-held hypotheses by EP Odum and others that suggest low-severity, high-frequency disturbances occurring in the region’s aging forests will, against intuition, maintain NEP at higher-than- expected rates by increasing ecosystem complexity, sustaining or enhancing NPP to a level that largely o sets rising C losses as heterotrophic respiration increases. This theoretical model is also supported by biological evidence and observations from the Forest Accelerated Succession Experiment in Michigan, USA. Ecosystems that experience high-severity disturbances that simplify ecosystem complexity can exhibit substantial declines in production during middle stages of succession. However, observations from these ecosystems have exerted a disproportionate in uence on assumptions regarding the trajectory and magnitude of age-related declines in forest production. We conclude that there is a wide ecological space for forests to maintain NPP and, in doing so, lessens the declines in NEP, with signi cant implications for the future of the North American carbon sink. Our intellectual frameworks for understanding forest C cycle dynamics and resilience need to catch up to our more complex and nuanced understanding of ecological succession.« less
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Parameterisation of Biome BGC to assess forest ecosystems in Africa
NASA Astrophysics Data System (ADS)
Gautam, Sishir; Pietsch, Stephan A.
2010-05-01
African forest ecosystems are an important environmental and economic resource. Several studies show that tropical forests are critical to society as economic, environmental and societal resources. Tropical forests are carbon dense and thus play a key role in climate change mitigation. Unfortunately, the response of tropical forests to environmental change is largely unknown owing to insufficient spatially extensive observations. Developing regions like Africa where records of forest management for long periods are unavailable the process-based ecosystem simulation model - BIOME BGC could be a suitable tool to explain forest ecosystem dynamics. This ecosystem simulation model uses descriptive input parameters to establish the physiology, biochemistry, structure, and allocation patterns within vegetation functional types, or biomes. Undocumented parameters for larger-resolution simulations are currently the major limitations to regional modelling in African forest ecosystems. This study was conducted to document input parameters for BIOME-BGC for major natural tropical forests in the Congo basin. Based on available literature and field measurements updated values for turnover and mortality, allometry, carbon to nitrogen ratios, allocation of plant material to labile, cellulose, and lignin pools, tree morphology and other relevant factors were assigned. Daily climate input data for the model applications were generated using the statistical weather generator MarkSim. The forest was inventoried at various sites and soil samples of corresponding stands across Gabon were collected. Carbon and nitrogen in the collected soil samples were determined from soil analysis. The observed tree volume, soil carbon and soil nitrogen were then compared with the simulated model outputs to evaluate the model performance. Furthermore, the simulation using Congo Basin specific parameters and generalised BIOME BGC parameters for tropical evergreen broadleaved tree species were also executed and the simulated results compared. Once the model was optimised for forests in the Congo basin it was validated against observed tree volume, soil carbon and soil nitrogen from a set of independent plots.
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Musavi, Talie; Migliavacca, Mirco; Reichstein, Markus; Kattge, Jens; Wirth, Christian; Black, T Andrew; Janssens, Ivan; Knohl, Alexander; Loustau, Denis; Roupsard, Olivier; Varlagin, Andrej; Rambal, Serge; Cescatti, Alessandro; Gianelle, Damiano; Kondo, Hiroaki; Tamrakar, Rijan; Mahecha, Miguel D
2017-01-23
The total uptake of carbon dioxide by ecosystems via photosynthesis (gross primary productivity, GPP) is the largest flux in the global carbon cycle. A key ecosystem functional property determining GPP is the photosynthetic capacity at light saturation (GPP sat ), and its interannual variability (IAV) is propagated to the net land-atmosphere exchange of CO 2 . Given the importance of understanding the IAV in CO 2 fluxes for improving the predictability of the global carbon cycle, we have tested a range of alternative hypotheses to identify potential drivers of the magnitude of IAV in GPP sat in forest ecosystems. Our results show that while the IAV in GPP sat within sites is closely related to air temperature and soil water availability fluctuations, the magnitude of IAV in GPP sat is related to stand age and biodiversity (R 2 = 0.55, P < 0.0001). We find that the IAV of GPP sat is greatly reduced in older and more diverse forests, and is higher in younger forests with few dominant species. Older and more diverse forests seem to dampen the effect of climate variability on the carbon cycle irrespective of forest type. Preserving old forests and their diversity would therefore be beneficial in reducing the effect of climate variability on Earth's forest ecosystems.
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NASA Technical Reports Server (NTRS)
McNeil, Brenden E.; deBeurs, Kirsten M.; Eshleman, Keith N.; Foster, Jane R.; Townsend, Philip A.
2007-01-01
Ephemeral disturbances, such as non-lethal insect defoliations and crown damage from meteorological events, can significantly affect the delivery of ecosystem services by helping maintain nitrogen (N) limitation in temperate forest ecosystems. However, the impacts of these disturbances are difficult to observe across the broad-scales at which they affect ecosystem function. Using remotely sensed measures and field data, we find support for the hypothesis that ephemeral disturbances help maintain landscape-wide ecosystem N limitation. Specifically, a phenology-based defoliation index derived from daily MODIS satellite imagery predicts three ecosystem responses from oak-dominated forested watersheds: elevated stream water N export (R(exp 2) = 0.48), decreased foliar N (R(exp 2) = 0.69, assessed with Hyperion imagery), and reduced vegetation growth vigor (R(exp 2) = 0.49, assessed with Landsat ETM+ imagery). The results indicate that ephemeral disturbances and other forest stressors may sustain N limitation by reducing the ability of trees to compete for--and retain--soil available N.
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Lamsal, Pramod; Kumar, Lalit; Atreya, Kishor; Pant, Krishna Prasad
2017-12-01
Climate change (CC) threatens ecosystems in both developed and developing countries. As the impacts of CC are pervasive, global, and mostly irreversible, it is gaining worldwide attention. Here we review vulnerability and impacts of CC on forest and freshwater wetland ecosystems. We particularly look at investigations undertaken at different geographic regions in order to identify existing knowledge gaps and possible implications from such vulnerability in the context of Nepal along with available adaptation programs and national-level policy supports. Different categories of impacts which are attributed to disrupting structure, function, and habitat of both forest and wetland ecosystems are identified and discussed. We show that though still unaccounted, many facets of forest and freshwater wetland ecosystems of Nepal are vulnerable and likely to be impacted by CC in the near future. Provisioning ecosystem services and landscape-level ecosystem conservation are anticipated to be highly threatened with future CC. Finally, the need for prioritizing CC research in Nepal is highlighted to close the existing knowledge gap along with the implementation of adaptation measures based on existing location specific traditional socio-ecological system.
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Thermal adaptation of net ecosystem exchange
Yuan, W.; Luo, Y.; Liang, S.; ...
2011-06-06
Thermal adaptation of gross primary production and ecosystem respiration has been well documented over broad thermal gradients. However, no study has examined their interaction as a function of temperature, i.e. the thermal responses of net ecosystem exchange of carbon (NEE). Here in this study, we constructed temperature response curves of NEE against temperature using 380 site-years of eddy covariance data at 72 forest, grassland and shrubland ecosystems located at latitudes ranging from ~29° N to 64° N. The response curves were used to define two critical temperatures: transition temperature (T b) at which ecosystem transfer from carbon source to sinkmore » and optimal temperature (T o) at which carbon uptake is maximized. T b was strongly correlated with annual mean air temperature. T o was strongly correlated with mean temperature during the net carbon uptake period across the study ecosystems. Our results imply that the net ecosystem exchange of carbon adapts to the temperature across the geographical range due to intrinsic connections between vegetation primary production and ecosystem respiration.« less
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Thermal adaptation of net ecosystem exchange
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yuan, W.; Luo, Y.; Liang, S.
Thermal adaptation of gross primary production and ecosystem respiration has been well documented over broad thermal gradients. However, no study has examined their interaction as a function of temperature, i.e. the thermal responses of net ecosystem exchange of carbon (NEE). Here in this study, we constructed temperature response curves of NEE against temperature using 380 site-years of eddy covariance data at 72 forest, grassland and shrubland ecosystems located at latitudes ranging from ~29° N to 64° N. The response curves were used to define two critical temperatures: transition temperature (T b) at which ecosystem transfer from carbon source to sinkmore » and optimal temperature (T o) at which carbon uptake is maximized. T b was strongly correlated with annual mean air temperature. T o was strongly correlated with mean temperature during the net carbon uptake period across the study ecosystems. Our results imply that the net ecosystem exchange of carbon adapts to the temperature across the geographical range due to intrinsic connections between vegetation primary production and ecosystem respiration.« less
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Leslie Brandt; Chris Swanston; Linda Parker; Maria Janowiak; Richard Birdsey; Louis Iverson; David Mladenoff; Patricia Butler
2012-01-01
Climate change is leading to direct and indirect impacts on forest tree species and ecosystems in northern Wisconsin. Land managers will need to prepare for and respond to these impacts, so we designed a workshop to identify forest management approaches that can enhance the ability of ecosystems in northern Wisconsin to cope with climate change and address how National...
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Disturbance dynamics of forested ecosystems
John A. Stanturf
2004-01-01
Forested ecosystems are dynamic, subject to natural developmental processes as well as natural and anthropogenic stresses and disturbances. Degradation is a related term. for lowered productive capacity from changes to forest structure of function (FAO. 2001). Degradation is not synonymous with disturbance, however; disturbance becomes degradation when natural...
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Ecosystem carbon density and allocation across a chronosequence of longleaf pine forests.
Samuelson, Lisa J; Stokes, Thomas A; Butnor, John R; Johnsen, Kurt H; Gonzalez-Benecke, Carlos A; Martin, Timothy A; Cropper, Wendell P; Anderson, Pete H; Ramirez, Michael R; Lewis, John C
2017-01-01
Forests can partially offset greenhouse gas emissions and contribute to climate change mitigation, mainly through increases in live biomass. We quantified carbon (C) density in 20 managed longleaf pine (Pinus palustris Mill.) forests ranging in age from 5 to 118 years located across the southeastern United States and estimated above- and belowground C trajectories. Ecosystem C stock (all pools including soil C) and aboveground live tree C increased nonlinearly with stand age and the modeled asymptotic maxima were 168 Mg C/ha and 80 Mg C/ha, respectively. Accumulation of ecosystem C with stand age was driven mainly by increases in aboveground live tree C, which ranged from <1 Mg C/ha to 74 Mg C/ha and comprised <1% to 39% of ecosystem C. Live root C (sum of below-stump C, ground penetrating radar measurement of lateral root C, and live fine root C) increased with stand age and represented 4-22% of ecosystem C. Soil C was related to site index, but not to stand age, and made up 39-92% of ecosystem C. Live understory C, forest floor C, downed dead wood C, and standing dead wood C were small fractions of ecosystem C in these frequently burned stands. Stand age and site index accounted for 76% of the variation in ecosystem C among stands. The mean root-to-shoot ratio calculated as the average across all stands (excluding the grass-stage stand) was 0.54 (standard deviation of 0.19) and higher than reports for other conifers. Long-term accumulation of live tree C, combined with the larger role of belowground accumulation of lateral root C than in other forest types, indicates a role of longleaf pine forests in providing disturbance-resistant C storage that can balance the more rapid C accumulation and C removal associated with more intensively managed forests. Although other managed southern pine systems sequester more C over the short-term, we suggest that longleaf pine forests can play a meaningful role in regional forest C management. © 2016 by the Ecological Society of America.
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Net ecosystem CO2 exchange of a primary tropical peat swamp forest in Sarawak, Malaysia
NASA Astrophysics Data System (ADS)
Tang Che Ing, A.; Stoy, P. C.; Melling, L.
2014-12-01
Tropical peat swamp forests are widely recognized as one of the world's most efficient ecosystems for the sequestration and storage of carbon through both their aboveground biomass and underlying thick deposits of peat. As the peat characteristics exhibit high spatial and temporal variability as well as the structural and functional complexity of forests, tropical peat ecosystems can act naturally as both carbon sinks and sources over their life cycles. Nonetheless, few reports of studies on the ecosystem-scale CO2 exchange of tropical peat swamp forests are available to-date and their present roles in the global carbon cycle remain uncertain. To quantify CO2 exchange and unravel the prevailing factors and potential underlying mechanism regulating net CO2 fluxes, an eddy covariance tower was erected in a tropical peat swamp forest in Sarawak, Malaysia. We observed that the diurnal and seasonal patterns of net ecosystem CO2 exchange (NEE) and its components (gross primary productivity (GPP) and ecosystem respiration (RE)) varied between seasons and years. Rates of NEE declined in the wet season relative to the dry season. Conversely, both the gross primary productivity (GPP) and ecosystem respiration (RE) were found to be higher during the wet season than the dry season, in which GPP was strongly negatively correlated with NEE. The average annual NEE was 385 ± 74 g C m-2 yr-1, indicating the primary peat swamp forest functioned as net source of CO2 to the atmosphere over the observation period.
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NASA Astrophysics Data System (ADS)
Yin, Kai; Zhang, Lei; Chen, Dima; Tian, Yichen; Zhang, Feifei; Wen, Meiping; Yuan, Chao
2016-05-01
The patterns and drivers of soil microbial communities in forest plantations remain inadequate although they have been extensively studied in natural forest and grassland ecosystems. In this study, using data from 12 subtropical plantation sites, we found that the overstory tree biomass and tree cover increased with increasing plantation age. However, there was a decline in the aboveground biomass and species richness of the understory herbs as plantation age increased. Biomass of all microbial community groups (i.e. fungi, bacteria, arbuscular mycorrhizal fungi, and actinomycete) decreased with increasing plantation age; however, the biomass ratio of fungi to bacteria did not change with increasing plantation age. Variation in most microbial community groups was mainly explained by the understory herb (i.e. herb biomass and herb species richness) and overstory trees (i.e. tree biomass and tree cover), while soils (i.e. soil moisture, soil organic carbon, and soil pH) explained a relative low percentage of the variation. Our results demonstrate that the understory herb layer exerts strong controls on soil microbial community in subtropical plantations. These findings suggest that maintenance of plantation health may need to consider the management of understory herb in order to increase the potential of plantation ecosystems as fast-response carbon sinks.
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Yin, Kai; Zhang, Lei; Chen, Dima; Tian, Yichen; Zhang, Feifei; Wen, Meiping; Yuan, Chao
2016-01-01
The patterns and drivers of soil microbial communities in forest plantations remain inadequate although they have been extensively studied in natural forest and grassland ecosystems. In this study, using data from 12 subtropical plantation sites, we found that the overstory tree biomass and tree cover increased with increasing plantation age. However, there was a decline in the aboveground biomass and species richness of the understory herbs as plantation age increased. Biomass of all microbial community groups (i.e. fungi, bacteria, arbuscular mycorrhizal fungi, and actinomycete) decreased with increasing plantation age; however, the biomass ratio of fungi to bacteria did not change with increasing plantation age. Variation in most microbial community groups was mainly explained by the understory herb (i.e. herb biomass and herb species richness) and overstory trees (i.e. tree biomass and tree cover), while soils (i.e. soil moisture, soil organic carbon, and soil pH) explained a relative low percentage of the variation. Our results demonstrate that the understory herb layer exerts strong controls on soil microbial community in subtropical plantations. These findings suggest that maintenance of plantation health may need to consider the management of understory herb in order to increase the potential of plantation ecosystems as fast-response carbon sinks. PMID:27243577
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Yin, Kai; Zhang, Lei; Chen, Dima; Tian, Yichen; Zhang, Feifei; Wen, Meiping; Yuan, Chao
2016-05-31
The patterns and drivers of soil microbial communities in forest plantations remain inadequate although they have been extensively studied in natural forest and grassland ecosystems. In this study, using data from 12 subtropical plantation sites, we found that the overstory tree biomass and tree cover increased with increasing plantation age. However, there was a decline in the aboveground biomass and species richness of the understory herbs as plantation age increased. Biomass of all microbial community groups (i.e. fungi, bacteria, arbuscular mycorrhizal fungi, and actinomycete) decreased with increasing plantation age; however, the biomass ratio of fungi to bacteria did not change with increasing plantation age. Variation in most microbial community groups was mainly explained by the understory herb (i.e. herb biomass and herb species richness) and overstory trees (i.e. tree biomass and tree cover), while soils (i.e. soil moisture, soil organic carbon, and soil pH) explained a relative low percentage of the variation. Our results demonstrate that the understory herb layer exerts strong controls on soil microbial community in subtropical plantations. These findings suggest that maintenance of plantation health may need to consider the management of understory herb in order to increase the potential of plantation ecosystems as fast-response carbon sinks.
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Patrick T. Hurley; Marla R. Emery
2017-01-01
Scholarship on the ecosystem services provided by urban forests has focused on regulating and supporting services, with a growing body of research examining provisioning and cultural ecosystem services from farms and gardens in metropolitan areas. Using the case of New York, New York, USA, we propose a method to assess the supply of potential provisioning ecosystem...
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Implications of sodium mass balance for interpreting the calcium cycle of a forested ecosystem
Scott W. Bailey; Donald C. Buso; Gene E. Likens
2003-01-01
Disturbance of forest ecosystems, such as that caused by harvesting or acid deposition, is thought to alter the ability of the ecosystem to retain nutrients. Although many watershed studies have suggested depletion of available calcium (Ca) pools, interpretation of ecosystem Ca mass balance has been limited by the difficulty in obtaining mineral weathering flux...
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Introduction to watershed ecosystem services: Chapter 1
Hall, Jefferson S.; Stallard, Robert F.; Kirn, Vanessa
2015-01-01
Humans derive a great number of goods and services from terrestrial ecosystems (Millennium Ecosystem Assessment, 2003, 2005). Some, like timber, fruits, bush meat, and other forest based food stuffs, are evident but others are not so obvious. Increasingly policy makers have realized the importance of forests and other ecosystems in sequestering carbon, as clearing of once vibrant vegetation or draining of swamps releases carbon dioxide (U.S. DOE, 2012) and where planting trees – particularly in the tropics - takes carbon dioxide out of the atmosphere (Bala et al., 2007). Scientists and conservationists have long called our attention to the value of Neotropical landscapes for biodiversity conservation as forests and other ecosystems harbor vast numbers of species. In recent decades conservationists and policy makers have also highlighted the potential of forests and other ecosystems to regulate stream flows (Ibáñez et al., 2002, Laurance, 2007 but also see Calder et al., 2007) and play a role in assuring clean water (Uriarte et al., 2011). All of these goods and services are part of what is collectively referred to as ecosystem services or goods and services that are provided to humanity through the unimpeded natural function of the ecosystem.
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Magrach, Ainhoa; Senior, Rebecca A; Rogers, Andrew; Nurdin, Deddy; Benedick, Suzan; Laurance, William F; Santamaria, Luis; Edwards, David P
2016-03-16
Selective logging is one of the major drivers of tropical forest degradation, causing important shifts in species composition. Whether such changes modify interactions between species and the networks in which they are embedded remain fundamental questions to assess the 'health' and ecosystem functionality of logged forests. We focus on interactions between lianas and their tree hosts within primary and selectively logged forests in the biodiversity hotspot of Malaysian Borneo. We found that lianas were more abundant, had higher species richness, and different species compositions in logged than in primary forests. Logged forests showed heavier liana loads disparately affecting slow-growing tree species, which could exacerbate the loss of timber value and carbon storage already associated with logging. Moreover, simulation scenarios of host tree local species loss indicated that logging might decrease the robustness of liana-tree interaction networks if heavily infested trees (i.e. the most connected ones) were more likely to disappear. This effect is partially mitigated in the short term by the colonization of host trees by a greater diversity of liana species within logged forests, yet this might not compensate for the loss of preferred tree hosts in the long term. As a consequence, species interaction networks may show a lagged response to disturbance, which may trigger sudden collapses in species richness and ecosystem function in response to additional disturbances, representing a new type of 'extinction debt'. © 2016 The Author(s).
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Magrach, Ainhoa; Senior, Rebecca A.; Rogers, Andrew; Nurdin, Deddy; Benedick, Suzan; Laurance, William F.; Santamaria, Luis; Edwards, David P.
2016-01-01
Selective logging is one of the major drivers of tropical forest degradation, causing important shifts in species composition. Whether such changes modify interactions between species and the networks in which they are embedded remain fundamental questions to assess the ‘health’ and ecosystem functionality of logged forests. We focus on interactions between lianas and their tree hosts within primary and selectively logged forests in the biodiversity hotspot of Malaysian Borneo. We found that lianas were more abundant, had higher species richness, and different species compositions in logged than in primary forests. Logged forests showed heavier liana loads disparately affecting slow-growing tree species, which could exacerbate the loss of timber value and carbon storage already associated with logging. Moreover, simulation scenarios of host tree local species loss indicated that logging might decrease the robustness of liana–tree interaction networks if heavily infested trees (i.e. the most connected ones) were more likely to disappear. This effect is partially mitigated in the short term by the colonization of host trees by a greater diversity of liana species within logged forests, yet this might not compensate for the loss of preferred tree hosts in the long term. As a consequence, species interaction networks may show a lagged response to disturbance, which may trigger sudden collapses in species richness and ecosystem function in response to additional disturbances, representing a new type of ‘extinction debt’. PMID:26936241
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Capturing heterogeneity: The role of a study area's extent for estimating mean throughfall
NASA Astrophysics Data System (ADS)
Zimmermann, Alexander; Voss, Sebastian; Metzger, Johanna Clara; Hildebrandt, Anke; Zimmermann, Beate
2016-11-01
The selection of an appropriate spatial extent of a sampling plot is one among several important decisions involved in planning a throughfall sampling scheme. In fact, the choice of the extent may determine whether or not a study can adequately characterize the hydrological fluxes of the studied ecosystem. Previous attempts to optimize throughfall sampling schemes focused on the selection of an appropriate sample size, support, and sampling design, while comparatively little attention has been given to the role of the extent. In this contribution, we investigated the influence of the extent on the representativeness of mean throughfall estimates for three forest ecosystems of varying stand structure. Our study is based on virtual sampling of simulated throughfall fields. We derived these fields from throughfall data sampled in a simply structured forest (young tropical forest) and two heterogeneous forests (old tropical forest, unmanaged mixed European beech forest). We then sampled the simulated throughfall fields with three common extents and various sample sizes for a range of events and for accumulated data. Our findings suggest that the size of the study area should be carefully adapted to the complexity of the system under study and to the required temporal resolution of the throughfall data (i.e. event-based versus accumulated). Generally, event-based sampling in complex structured forests (conditions that favor comparatively long autocorrelations in throughfall) requires the largest extents. For event-based sampling, the choice of an appropriate extent can be as important as using an adequate sample size.
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Invasive non-native species' provision of refugia for endangered native species.
Chiba, Satoshi
2010-08-01
The influence of non-native species on native ecosystems is not predicted easily when interspecific interactions are complex. Species removal can result in unexpected and undesired changes to other ecosystem components. I examined whether invasive non-native species may both harm and provide refugia for endangered native species. The invasive non-native plant Casuarina stricta has damaged the native flora and caused decline of the snail fauna on the Ogasawara Islands, Japan. On Anijima in 2006 and 2009, I examined endemic land snails in the genus Ogasawarana. I compared the density of live specimens and frequency of predation scars (from black rats [Rattus rattus]) on empty shells in native vegetation and Casuarina forests. The density of land snails was greater in native vegetation than in Casuarina forests in 2006. Nevertheless, radical declines in the density of land snails occurred in native vegetation since 2006 in association with increasing predation by black rats. In contrast, abundance of Ogasawarana did not decline in the Casuarina forest, where shells with predation scars from rats were rare. As a result, the density of snails was greater in the Casuarina forest than in native vegetation. Removal of Casuarina was associated with an increased proportion of shells with predation scars from rats and a decrease in the density of Ogasawarana. The thick and dense litter of Casuarina appears to provide refugia for native land snails by protecting them from predation by rats; thus, eradication of rats should precede eradication of Casuarina. Adaptive strategies, particularly those that consider the removal order of non-native species, are crucial to minimizing the unintended effects of eradication on native species. In addition, my results suggested that in some cases a given non-native species can be used to mitigate the impacts of other non-native species on native species.
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You, Yeming; Wang, Juan; Huang, Xueman; Tang, Zuoxin; Liu, Shirong; Sun, Osbert J
2014-03-01
Forest soils store vast amounts of terrestrial carbon, but we are still limited in mechanistic understanding on how soil organic carbon (SOC) stabilization or turnover is controlled by biotic and abiotic factors in forest ecosystems. We used phospholipid fatty acids (PLFAs) as biomarker to study soil microbial community structure and measured activities of five extracellular enzymes involved in the degradation of cellulose (i.e., β-1,4-glucosidase and cellobiohydrolase), chitin (i.e., β-1,4-N-acetylglucosaminidase), and lignin (i.e., phenol oxidase and peroxidase) as indicators of soil microbial functioning in carbon transformation or turnover across varying biotic and abiotic conditions in a typical temperate forest ecosystem in central China. Redundancy analysis (RDA) was performed to determine the interrelationship between individual PFLAs and biotic and abiotic site factors as well as the linkage between soil microbial structure and function. Path analysis was further conducted to examine the controls of site factors on soil microbial community structure and the regulatory pathway of changes in SOC relating to microbial community structure and function. We found that soil microbial community structure is strongly influenced by water, temperature, SOC, fine root mass, clay content, and C/N ratio in soils and that the relative abundance of Gram-negative bacteria, saprophytic fungi, and actinomycetes explained most of the variations in the specific activities of soil enzymes involved in SOC transformation or turnover. The abundance of soil bacterial communities is strongly linked with the extracellular enzymes involved in carbon transformation, whereas the abundance of saprophytic fungi is associated with activities of extracellular enzymes driving carbon oxidation. Findings in this study demonstrate the complex interactions and linkage among plant traits, microenvironment, and soil physiochemical properties in affecting SOC via microbial regulations.
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NASA Astrophysics Data System (ADS)
Goetz, S. J.; Rogers, B. M.; Mack, M. C.; Goulden, M.; Pastick, N. J.; Berner, L. T.; Fisher, J.
2017-12-01
The Arctic and boreal forest biomes have global significance in terms of climate feedbacks associated with land surface interactions with the atmosphere. Changes in Arctic tundra and boreal forest ecosystem productivity and fire disturbance feedbacks have been well documented in recent years, but findings are often only locally relevant and are sometimes inconsistent among research teams. Part of these inconsistencies lie in utilization of different data sets and time periods considered. Integrated approaches are thus needed to adequately address changes in these ecosystems in order to assess consistency and variability of change, as well as ecosystem vulnerability and resiliency across spatial and temporal scales. Ultimately this can best be accomplished via multiple lines of evidence including remote sensing, field measurements and various types of data-constrained models. We will discuss some recent results integrating multiple lines of evidence for directional ecosystem change in the Arctic and boreal forest biomes of North America. There is increasing evidence for widespread spatial and temporal variability in Arctic and boreal ecosystem productivity changes that are strongly influenced by cycles of changing fire disturbance severity and its longer-term implications (i.e legacy effects). Integrated, multi-approach research, like that currently underway as part of the NASA-led Arctic Boreal Vulnerability Experiment (above.nasa.gov), is an effective way to capture the complex mechanisms that drive patterns and directionality of ecosystem structure and function, and ultimately determine feedbacks to environmental change, particularly in the context of global climate change. Additional ongoing ABoVE research will improve our understanding of the consequences of environmental changes underway, as well as increase our confidence in making projections of the ecosystem responses, vulnerability and resilience to change. ABoVE will also build a lasting legacy of collaboration through an expanded knowledge base, provision of key datasets to a broader network of researchers and resource managers, and the development of data products and knowledge designed to foster decision support and applied research partnerships with broad societal relevance.
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Shanin, V N; Mikhaĭlov, A V; Bykhovets, S S; Komarov, A S
2010-01-01
The individually oriented system of the EFIMOD models simulating carbon and nitrogen flows in forest ecosystems has been used for forecasting the response of forest ecosystems to various forest exploitation regimes with climate change. As input data the forest management materials for the Manturovskii forestry of the Kostroma region were used. It has been shown that increase of mid-annual temperatures and rainfall influence the redistribution of carbon and nitrogen supply in organic form: supply increase of these elements in phytomass simultaneously with depletion of them in soil occurred. The most carbon and nitrogen accumulation in forest ecosystems occurs in the scenario without felling. In addition, in this scenario only the ecosystems of the modeling territory function as a carbon drain; in the other two scenarios (with selective and total felling) they function as a source of carbon. Climate changes greatly influence the decomposition rate of organic matter in soil, which leads to increased emission of carbonic acid. The second consequence of the increase in the destruction rate is nitrogen increase in the soil in a form available for plants that entails production increase of plantations.
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Climate changes impact the surface albedo of a forest ecosystem based on MODIS satellite data
NASA Astrophysics Data System (ADS)
Zoran, M. A.; Nemuc, A. V.
2007-10-01
Surface albedo is one of the most important biophysical parameter responsible for energy balance control and the surface temperature and boundary-layer structure of the atmosphere. Forest land surface albedo is also highly variable temporally showing both diurnal as well as seasonal variations. In forest systems, albedo controls the microclimate conditions which affects ecosystem physical, physiological, and biogeochemical processes such as energy balance, evapotranspiration, photosynthesis. Due to anthropogenic and natural factors, land cover and land use changes result is the land surfaces albedo change. The main aim of this paper is to investigate the albedo patterns due to the impact of atmospheric pollution and climate variations of a forest ecosystem Branesti-Cernica, placed to the North-East of Bucharest city, Romania based on satellite Landsat ETM+, IKONOS and MODIS data and climate station observations. Our study focuses on 3 years of data (2003-2005), each of which had a different climatic regime. As the physical climate system is very sensitive to surface albedo, forest ecosystems could significantly feedback to the projected climate change modeling scenarios through albedo changes. The results of this research have a number of applications in weather forecasting, climate change, and forest ecosystem studies.
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NASA Astrophysics Data System (ADS)
Yi, K.; Wenzel, M. K.; Maxwell, J. T.; Novick, K. A.; Gray, A.; Roman, D. T.
2015-12-01
Drought is expected to occur more frequently and intensely in the future, and many studies have suggested frequent and intense droughts can significantly alter carbon and water cycling in forest ecosystems, consequently decreasing the ability of forests to assimilate carbon. Predicting the impact of drought on forest ecosystem processes requires an understanding of species-specific responses to drought, especially in eastern US where species composition is highly dynamic. An emerging approach for describing species-specific drought response is to classify the plant water use strategy into isohydric and anisohydric behaviors. Trees utilizing isohydric behavior regulate water potential by closing stomata to reduce water loss during drought conditions, while anisohydric trees allow water potential to drop by sustaining stomatal conductance, but with the risk of hydraulic failure caused by cavitation of xylem tissues. Since catastrophic cavitation occurs infrequently in the relatively wet eastern U.S., we hypothesize that 1) tree growth of isohydric trees will be more limited during the drought than the anisohydric trees due to decreased stomatal conductance, but 2) variation in intrinsic water use efficient (iWUE) during drought in isohydric trees will mediate the effects of drought on carbon assimilation. We will test these hypotheses by 1) analyzing tree-ring chronologies and dendrometer data on productivity, and 2) estimating intrinsic water use efficiency (iWUE) at multiple scales by analyzing gas exchange data for the leaf-level, inter-annual variability of d13C in tree stem cores for the tree-level, and eddy covariance technique for the stand-level. Our study site is the Morgan-Monroe State Forest (Indiana, USA). A 46 m flux tower has been continuously recording the carbon, water and energy fluxes, and tree diameter has been measured every 2 weeks using dendrometers, since 1998. Additional research, including gas exchange measurements performed during the growing seasons of 2011-2013 and tree-ring chronologies collected in 2014 and 2015, enable us to assess the long-term impact of climate on the ecosystem processes at multiple scales. Finally, the severe drought experienced in this region in 2012 will help us evaluate how productivity and iWUE respond to an especially severe drought event.
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Bradford, John B.; Jensen, Nicholas R.; Domke, Grant M.; D’Amato, Anthony W.
2013-01-01
Forested ecosystems contain the majority of the world’s terrestrial carbon, and forest management has implications for regional and global carbon cycling. Carbon stored in forests changes with stand age and is affected by natural disturbance and timber harvesting. We examined how harvesting and disturbance interact to influence forest carbon stocks over the Superior National Forest, in northern Minnesota. Forest inventory data from the USDA Forest Service, Forest Inventory and Analysis program were used to characterize current forest age structure and quantify the relationship between age and carbon stocks for eight forest types. Using these findings, we simulated the impact of alternative management scenarios and natural disturbance rates on forest-wide terrestrial carbon stocks over a 100-year horizon. Under low natural mortality, forest-wide total ecosystem carbon stocks increased when 0% or 40% of planned harvests were implemented; however, the majority of forest-wide carbon stocks decreased with greater harvest levels and elevated disturbance rates. Our results suggest that natural disturbance has the potential to exert stronger influence on forest carbon stocks than timber harvesting activities and that maintaining carbon stocks over the long-term may prove difficult if disturbance frequency increases in response to climate change.
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Stephen Handler; Matthew J. Duveneck; Louis Iverson; Emily Peters; Robert M. Scheller; Kirk R. Wythers; Leslie Brandt; Patricia Butler; Maria Janowiak; P. Danielle Shannon; Chris Swanston; Amy Clark Eagle; Joshua G. Cohen; Rich Corner; Peter B. Reich; Tim Baker; Sophan Chhin; Eric Clark; David Fehringer; Jon Fosgitt; James Gries; Christine Hall; Kimberly R. Hall; Robert Heyd; Christopher L. Hoving; Ines Ibáñez; Don Kuhr; Stephen Matthews; Jennifer Muladore; Knute Nadelhoffer; David Neumann; Matthew Peters; Anantha Prasad; Matt Sands; Randy Swaty; Leiloni Wonch; Jad Daley; Mae Davenport; Marla R. Emery; Gary Johnson; Lucinda Johnson; David Neitzel; Adena Rissman; Chadwick Rittenhouse; Robert. Ziel
2014-01-01
Forests in northern Michigan will be affected directly and indirectly by a changing climate during the next 100 years. This assessment evaluates the vulnerability of forest ecosystems in Michigan's eastern Upper Peninsula and northern Lower Peninsula to a range of future climates. Information on current forest conditions, observed climate trends, projected climate...
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Christopher W. Woodall; Jacques Rondeux; Pieter J. Verkerk; G& #246; ran St& #229; hl
2009-01-01
Efforts to assess forest ecosystem carbon stocks, biodiversity, and fire hazards have spurred the need for comprehensive assessments of forest ecosystem dead wood (DW) components around the world. Currently, information regarding the prevalence, status, and methods of DW inventories occurring in the world's forested landscapes is scattered. The goal of this study...
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Christopher W. Woodall; Jacques Rondeux; Pieter J. Verkerk; Goran Stahl
2009-01-01
Efforts to assess forest ecosystem carbon stocks, biodiversity, and fire hazards have spurred the need for comprehensive assessments of forest ecosystem dead wood (DW) attributes around the world. Currently, information regarding the prevalence, status, and methods of DW inventories occurring in the world?s forested landscapes is scattered. The goal of this study is to...
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Johann N. Bruhn; James J. Wetteroff; Jeanne D. Mihail; Randy G. Jensen; James B. Pickens
2002-01-01
The Missouri Ozark Forest Ecosystem Project (MOFEP) is a long-term, multidisciplinary, landscape-based research program studying effects of even-aged (EAM), uneven-aged (UAM), and no-harvest (NHM) management on forest communities. The first MOFEP timber harvests occurred from May through November 1996. Harvest- related disturbance occurred on 69 of 180 permanent 0.2-ha...
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Forest health in the Blue Mountains: a management strategy for fire-adapted ecosystems.
R.W. Mutch; S.F. Arno; J.K. Brown; C.E. Carlson; R.D. Ottmar; J.L. Peterson
1993-01-01
The fire-adapted forests of the Blue Mountains are suffering from a forest health problem of catastrophic proportions. Contributing to the decline of forest health are such factors as the extensive harvesting of the western larch and ponderosa pine overstory during the 1900s, attempted exclusion of fire from a fire-dependent ecosystem, and the continuing drought. The...
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Susan Will-Wolf; Randall S. Morin; Mark J. Ambrose; Kurt Riitters; Sarah Jovan
2014-01-01
Lichen community composition is well known for exhibiting response to air pollution, and to macroenvironmental and microenvironmental variables. Lichens are useful indicators of air quality impact, forest health, and forest ecosystem integrity across the United States (McCune 2000, reviews in Nimis and others 2002, USDA Forest Service 2007).
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Dwight Scarbrough; Jennifer Juzwik
2004-01-01
Various native and exotic insects and diseases affect the forest ecosystems of the Hoosier-Shawnee Ecological Assessment Area. Defoliating insects have had the greatest effects in forests where oak species predominate. Increases in oak decline are expected with the imminent establishment of the European gypsy moth. Insects and pathogens of the pine forests are...
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Svetlana A. (Kushch) Schroder; Sandor F. Toth; Robert L. Deal; Gregory J. Ettl
2016-01-01
Forest owners worldwide are increasingly interested in managing forests to provide a broad suite of Ecosystem services, balancing multiple objectives and evaluating management activities in terms of Potential tradeoffs. We describe a multi-objective mathematical programming model to quantify tradeoffs in expected sediment delivery and the preservation of Northern...
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Forest changes since Euro-American settlement and ecosystem restoration in the Lake Tahoe Basin, USA
Alan H. Taylor
2007-01-01
Pre Euro-American settlement forest structure and fire regimes for Jeffrey pine-white fir, red fir-western white pine, and lodgepole pine forests were quantified using stumps from trees cut in the 19th century to establish a baseline reference for ecosystem management in the Lake Tahoe Basin. Contemporary forests varied in different ways compared...
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Effects of roads on elk: implications for management in forested ecosystems.
Mary M. Rowland; Michael J. Wisdom; Bruce K. Johnson; Mark A. Penninger
2004-01-01
The effects of roads on both habitat and population responses of elk (Cervus elaphus) have been of keen interest to foresters and ungulate biologists for the last half century. Increased timber harvest in national forests, beginning in the 1960s, led to a proliferation of road networks in forested ecosystems inhabited by elk (Hieb 1976, Lyon and...
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Steve Zack; William F. Laudenslayer; Luke George; Carl Skinner; William Oliver
1999-01-01
At two different locations in northeast California, an interdisciplinary team of scientists is initiating long-term studies to quantify the effects of forest manipulations intended to accelerate andlor enhance late-successional structure of eastside pine forest ecosystems. One study, at Blacks Mountain Experimental Forest, uses a split-plot, factorial, randomized block...
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Andrew B. Carey; David R. Thysell; Angus W. Brodie
1999-01-01
The Forest Ecosystem Study (FES) came about as an early response to the need for innovative silvicultural methods designed to stimulate development of late-successional attributes in managed forestsâa need ensuing from the exceptional and longstanding controversies over old-growth forests and endangered species concerns in the Pacific Northwest. In 1991, scientists...
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Keith Reynolds; Philip Murphy; Steven Paplanus
2017-01-01
Spatial decision support systems for forest management have steadily evolved over the past 20+ years in order to better address the complexities of contemporary forest management issues such as the sustainability and resilience of ecosystems on forested landscapes. In this paper, we describe and illustrate new features of the Ecosystem Management Decision Support (EMDS...
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Carbon Storages in Plantation Ecosystems in Sand Source Areas of North Beijing, China
Liu, Xiuping; Zhang, Wanjun; Cao, Jiansheng; Shen, Huitao; Zeng, Xinhua; Yu, Zhiqiang; Zhao, Xin
2013-01-01
Afforestation is a mitigation option to reduce the increased atmospheric carbon dioxide levels as well as the predicted high possibility of climate change. In this paper, vegetation survey data, statistical database, National Forest Resource Inventory database, and allometric equations were used to estimate carbon density (carbon mass per hectare) and carbon storage, and identify the size and spatial distribution of forest carbon sinks in plantation ecosystems in sand source areas of north Beijing, China. From 2001 to the end of 2010, the forest areas increased more than 2.3 million ha, and total carbon storage in forest ecosystems was 173.02 Tg C, of which 82.80 percent was contained in soil in the top 0–100 cm layer. Younger forests have a large potential for enhancing carbon sequestration in terrestrial ecosystems than older ones. Regarding future afforestation efforts, it will be more effective to increase forest area and vegetation carbon density through selection of appropriate tree species and stand structure according to local climate and soil conditions, and application of proper forest management including land-shaping, artificial tending and fencing plantations. It would be also important to protect the organic carbon in surface soils during forest management. PMID:24349223
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NASA Astrophysics Data System (ADS)
Abelleira, O. J.
2011-12-01
The African tulip tree, Spathodea campanulata, has been introduced to and dominates many post-agricultural secondary forests in the moist tropics, particularly in islands. Some consider these novel forests have null to negative 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 alluvial and karst substrates in northern Puerto Rico. These substrates have different water drainage properties and I hypothesized that (1) annual leaf fall mass and seasonality would differ between substrate types; because (2) leaf fall would be related to water availability and seasonality. I used analysis of variance to compare annual and biweekly litterfall mass across three sites on each substrate type, and multiple linear regression analysis to relate biweekly litterfall to environmental variables. Litterfall mass was high (13.8 Mg/ha/yr, n = 6, SE = 0.60) yet its components did not differ by substrate type except for reproductive part mass which was higher on karst due to more S. campanulata flowers. Leaf fall had a bimodal seasonality and was negatively related to the number of dry days indicating it occurs when water is readily available or in excess as during floods. Observations show systematic leaf senescence in this deciduous species can be caused by water and nutrient demand from flowering. Litterfall mass and seasonality of novel S. campanulata forests is similar to that of native forests in Puerto Rico, yet flower fall appears to be higher than that of tropical forests worldwide. The environmental variables that affect litterfall seasonality and canopy phenology are similar to those in tropical forests in Puerto Rico and elsewhere. Litterfall seasonality and canopy phenology regulate understory microclimate, and influence the establishment and growth of juvenile trees and other organisms within S. campanulata forests. Thus, the forest ecosystem processes and properties restored by novel S. campanulata forests facilitate tree species establishment, growth, and turnover in deforested, abandoned, and degraded agricultural lands in Puerto Rico. This study illustrates how anthropogenic land use change and species transport interact to modify the phenology of current forest cover, and suggests that anthropogenic climate change that modifies seasonal patterns of tempreature and precipitation will have an influence on the litterfall and phenology of novel S. campanulata forests.
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Restoring a legacy: longleaf pine research at the Forest Service Escambia Experimental Forest
Kristina F. Connor; Dale G. Brockway; William D. Boyer
2014-01-01
Longleaf pine ecosystems are a distinct part of the forest landscape in the southeastern USA. These biologically diverse ecosystems, the native habitat of numerous federally listed species, once dominated more than 36.4 million ha but now occupy only 1.4 million ha of forested land in the region. The Escambia Experimental Forest was established in 1947 through a 99-...
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IMPACTS OF AIR POLLUTION AND CLIMATE CHANGE ON FOREST ECOSYSTEMS - EMERGING RESEARCH NEEDS
Outcomes from the 22nd meeting for Specialists in Air Pollution Effects on Forest Ecosystems "Forests under Anthropogenic Pressure - Effects of Air Pollution, Climate Change and Urban Development", September 10-16, 2006, Riverside, CA, USA are summarized. Tropospheric ozone is st...
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Land-use intensification effects on functional properties in tropical plant communities.
Carreño-Rocabado, Geovana; Peña-Claros, Marielos; Bongers, Frans; Díaz, Sandra; Quetier, Fabien; Chuviña, José; Poorter, Lourens
2016-01-01
There is consensus that plant diversity and ecosystem processes are negatively affected by land-use intensification (LUI), but, at the same time, there is empirical evidence that a large heterogeneity can be found in the responses. This heterogeneity is especially poorly understood in tropical ecosystems. We evaluated changes in community functional properties across five common land-use types in the wet tropics with different land-use intensity: mature forest, logged forest, secondary forest, agricultural land, and pastureland, located in the lowlands of Bolivia. For the dominant plant species, we measured 12 functional response traits related to their life history, acquisition and conservation of resources, plant domestication, and breeding. We used three single-trait metrics to describe community functional properties: community abundance-weighted mean (CWM) traits values, coefficient of variation, and kurtosis of distribution. The CWM of all 12 traits clearly responded to LUI. Overall, we found that an increase in LUI resulted in communities dominated by plants with acquisitive leaf trait values. However, contrary to our expectations, secondary forests had more conservative trait values (i.e., lower specific leaf area) than mature and logged forest, probably because they were dominated by palm species. Functional variation peaked at intermediate land-use intensity (high coefficient of variation and low kurtosis), which included secondary forest but, unexpectedly, also agricultural land, which is an intensely managed system. The high functional variation of these systems is due to a combination of how response traits (and species) are filtered out by biophysical filters and how management practices introduced a range of exotic species and their trait values into the local species pool. Our results showed that, at local scales and depending on prevailing environmental and management practices, LUI does not necessarily result in communities with more acquisitive trait values or with less functional variation. Instead of the widely expected negative impacts of LUI on plant diversity, we found varying responses of functional variation, with possible repercussions on many ecosystem services. These findings provide a background for actively mitigating negative effects of LUI while meeting the needs of local communities that rely mainly on provisioning ecosystem services for their livelihoods.
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[Measurement model of carbon emission from forest fire: a review].
Hu, Hai-Qing; Wei, Shu-Jing; Jin, Sen; Sun, Long
2012-05-01
Forest fire is the main disturbance factor for forest ecosystem, and an important pathway of the decrease of vegetation- and soil carbon storage. Large amount of carbonaceous gases in forest fire can release into atmosphere, giving remarkable impacts on the atmospheric carbon balance and global climate change. To scientifically and effectively measure the carbonaceous gases emission from forest fire is of importance in understanding the significance of forest fire in the carbon balance and climate change. This paper reviewed the research progress in the measurement model of carbon emission from forest fire, which covered three critical issues, i. e., measurement methods of forest fire-induced total carbon emission and carbonaceous gases emission, affecting factors and measurement parameters of measurement model, and cause analysis of the uncertainty in the measurement of the carbon emissions. Three path selections to improve the quantitative measurement of the carbon emissions were proposed, i. e., using high resolution remote sensing data and improving algorithm and estimation accuracy of burned area in combining with effective fuel measurement model to improve the accuracy of the estimated fuel load, using high resolution remote sensing images combined with indoor controlled environment experiments, field measurements, and field ground surveys to determine the combustion efficiency, and combining indoor controlled environment experiments with field air sampling to determine the emission factors and emission ratio.
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Wood, Tana E.; Cavaleri, Molly A.; Reed, Sasha C.
2012-01-01
Tropical forests play a major role in regulating global carbon (C) fluxes and stocks, and even small changes to C cycling in this productive biome could dramatically affect atmospheric carbon dioxide (CO2) concentrations. Temperature is expected to increase over all land surfaces in the future, yet we have a surprisingly poor understanding of how tropical forests will respond to this significant climatic change. Here we present a contemporary synthesis of the existing data and what they suggest about how tropical forests will respond to increasing temperatures. Our goals were to: (i) determine whether there is enough evidence to support the conclusion that increased temperature will affect tropical forest C balance; (ii) if there is sufficient evidence, determine what direction this effect will take; and, (iii) establish what steps should to be taken to resolve the uncertainties surrounding tropical forest responses to increasing temperatures. We approach these questions from a mass-balance perspective and therefore focus primarily on the effects of temperature on inputs and outputs of C, spanning microbial- to ecosystem-scale responses. We found that, while there is the strong potential for temperature to affect processes related to C cycling and storage in tropical forests, a notable lack of data combined with the physical, biological and chemical diversity of the forests themselves make it difficult to resolve this issue with certainty. We suggest a variety of experimental approaches that could help elucidate how tropical forests will respond to warming, including large-scale in situ manipulation experiments, longer term field experiments, the incorporation of a range of scales in the investigation of warming effects (both spatial and temporal), as well as the inclusion of a diversity of tropical forest sites. Finally, we highlight areas of tropical forest research where notably few data are available, including temperature effects on: nutrient cycling, heterotrophic versus autotrophic respiration, thermal acclimation versus substrate limitation of plant and microbial communities, below-ground C allocation, species composition (plant and microbial), and the hydraulic architecture of roots. Whether or not tropical forests will become a source or a sink of C in a warmer world remains highly uncertain. Given the importance of these ecosystems to the global C budget, resolving this uncertainty is a primary research priority.
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Woodcock, Paul; Edwards, David P.; Newton, Rob J.; Vun Khen, Chey; Bottrell, Simon H.; Hamer, Keith C.
2013-01-01
Trophic organisation defines the flow of energy through ecosystems and is a key component of community structure. Widespread and intensifying anthropogenic disturbance threatens to disrupt trophic organisation by altering species composition and relative abundances and by driving shifts in the trophic ecology of species that persist in disturbed ecosystems. We examined how intensive disturbance caused by selective logging affects trophic organisation in the biodiversity hotspot of Sabah, Borneo. Using stable nitrogen isotopes, we quantified the positions in the food web of 159 leaf-litter ant species in unlogged and logged rainforest and tested four predictions: (i) there is a negative relationship between the trophic position of a species in unlogged forest and its change in abundance following logging, (ii) the trophic positions of species are altered by logging, (iii) disturbance alters the frequency distribution of trophic positions within the ant assemblage, and (iv) disturbance reduces food chain length. We found that ant abundance was 30% lower in logged forest than in unlogged forest but changes in abundance of individual species were not related to trophic position, providing no support for prediction (i). However, trophic positions of individual species were significantly higher in logged forest, supporting prediction (ii). Consequently, the frequency distribution of trophic positions differed significantly between unlogged and logged forest, supporting prediction (iii), and food chains were 0.2 trophic levels longer in logged forest, the opposite of prediction (iv). Our results demonstrate that disturbance can alter trophic organisation even without trophically-biased changes in community composition. Nonetheless, the absence of any reduction in food chain length in logged forest suggests that species-rich arthropod food webs do not experience trophic downgrading or a related collapse in trophic organisation despite the disturbance caused by logging. These food webs appear able to bend without breaking in the face of some forms of anthropogenic disturbance. PMID:23593302
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Woodcock, Paul; Edwards, David P; Newton, Rob J; Vun Khen, Chey; Bottrell, Simon H; Hamer, Keith C
2013-01-01
Trophic organisation defines the flow of energy through ecosystems and is a key component of community structure. Widespread and intensifying anthropogenic disturbance threatens to disrupt trophic organisation by altering species composition and relative abundances and by driving shifts in the trophic ecology of species that persist in disturbed ecosystems. We examined how intensive disturbance caused by selective logging affects trophic organisation in the biodiversity hotspot of Sabah, Borneo. Using stable nitrogen isotopes, we quantified the positions in the food web of 159 leaf-litter ant species in unlogged and logged rainforest and tested four predictions: (i) there is a negative relationship between the trophic position of a species in unlogged forest and its change in abundance following logging, (ii) the trophic positions of species are altered by logging, (iii) disturbance alters the frequency distribution of trophic positions within the ant assemblage, and (iv) disturbance reduces food chain length. We found that ant abundance was 30% lower in logged forest than in unlogged forest but changes in abundance of individual species were not related to trophic position, providing no support for prediction (i). However, trophic positions of individual species were significantly higher in logged forest, supporting prediction (ii). Consequently, the frequency distribution of trophic positions differed significantly between unlogged and logged forest, supporting prediction (iii), and food chains were 0.2 trophic levels longer in logged forest, the opposite of prediction (iv). Our results demonstrate that disturbance can alter trophic organisation even without trophically-biased changes in community composition. Nonetheless, the absence of any reduction in food chain length in logged forest suggests that species-rich arthropod food webs do not experience trophic downgrading or a related collapse in trophic organisation despite the disturbance caused by logging. These food webs appear able to bend without breaking in the face of some forms of anthropogenic disturbance.
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Restoring and managing low-severity fire in dry-forest landscapes of the western USA.
Baker, William L
2017-01-01
Low-severity fires that killed few canopy trees played a significant historical role in dry forests of the western USA and warrant restoration and management, but historical rates of burning remain uncertain. Past reconstructions focused on on dating fire years, not measuring historical rates of burning. Past statistics, including mean composite fire interval (mean CFI) and individual-tree fire interval (mean ITFI) have biases and inaccuracies if used as estimators of rates. In this study, I used regression, with a calibration dataset of 96 cases, to test whether these statistics could accurately predict two equivalent historical rates, population mean fire interval (PMFI) and fire rotation (FR). The best model, using Weibull mean ITFI, had low prediction error and R2adj = 0.972. I used this model to predict historical PMFI/FR at 252 sites spanning dry forests. Historical PMFI/FR for a pool of 342 calibration and predicted sites had a mean of 39 years and median of 30 years. Short (< 25 years) mean PMFI/FRs were in Arizona and New Mexico and scattered in other states. Long (> 55 years) mean PMFI/FRs were mainly from northern New Mexico to South Dakota. Mountain sites often had a large range in PMFI/FR. Nearly all 342 estimates are for old forests with a history of primarily low-severity fire, found across only about 34% of historical dry-forest area. Frequent fire (PMFI/FR < 25 years) was found across only about 14% of historical dry-forest area, with 86% having multidecadal rates of low-severity fire. Historical fuels (e.g., understory shrubs and small trees) could fully recover between multidecadal fires, allowing some denser forests and some ecosystem processes and wildlife habitat to be less limited by fire. Lower historical rates mean less restoration treatment is needed before beginning managed fire for resource benefits, where feasible. Mimicking patterns of variability in historical low-severity fire regimes would likely benefit biological diversity and ecosystem functioning.
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Restoring and managing low-severity fire in dry-forest landscapes of the western USA
2017-01-01
Low-severity fires that killed few canopy trees played a significant historical role in dry forests of the western USA and warrant restoration and management, but historical rates of burning remain uncertain. Past reconstructions focused on on dating fire years, not measuring historical rates of burning. Past statistics, including mean composite fire interval (mean CFI) and individual-tree fire interval (mean ITFI) have biases and inaccuracies if used as estimators of rates. In this study, I used regression, with a calibration dataset of 96 cases, to test whether these statistics could accurately predict two equivalent historical rates, population mean fire interval (PMFI) and fire rotation (FR). The best model, using Weibull mean ITFI, had low prediction error and R2adj = 0.972. I used this model to predict historical PMFI/FR at 252 sites spanning dry forests. Historical PMFI/FR for a pool of 342 calibration and predicted sites had a mean of 39 years and median of 30 years. Short (< 25 years) mean PMFI/FRs were in Arizona and New Mexico and scattered in other states. Long (> 55 years) mean PMFI/FRs were mainly from northern New Mexico to South Dakota. Mountain sites often had a large range in PMFI/FR. Nearly all 342 estimates are for old forests with a history of primarily low-severity fire, found across only about 34% of historical dry-forest area. Frequent fire (PMFI/FR < 25 years) was found across only about 14% of historical dry-forest area, with 86% having multidecadal rates of low-severity fire. Historical fuels (e.g., understory shrubs and small trees) could fully recover between multidecadal fires, allowing some denser forests and some ecosystem processes and wildlife habitat to be less limited by fire. Lower historical rates mean less restoration treatment is needed before beginning managed fire for resource benefits, where feasible. Mimicking patterns of variability in historical low-severity fire regimes would likely benefit biological diversity and ecosystem functioning. PMID:28199416
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NASA Astrophysics Data System (ADS)
Viers, J. H.
2013-12-01
Integrating citizen scientists into ecological informatics research can be difficult due to limited opportunities for meaningful engagement given vast data streams. This is particularly true for analysis of remotely sensed data, which are increasingly being used to quantify ecosystem services over space and time, and to understand how land uses deliver differing values to humans and thus inform choices about future human actions. Carbon storage and sequestration are such ecosystem services, and recent environmental policy advances in California (i.e., AB 32) have resulted in a nascent carbon market that is helping fuel the restoration of riparian forests in agricultural landscapes. Methods to inventory and monitor aboveground carbon for market accounting are increasingly relying on hyperspatial remotely sensed data, particularly the use of light detection and ranging (LiDAR) technologies, to estimate biomass. Because airborne discrete return LiDAR can inexpensively capture vegetation structural differences at high spatial resolution (< 1 m) over large areas (> 1000 ha), its use is rapidly increasing, resulting in vast stores of point cloud and derived surface raster data. While established algorithms can quantify forest canopy structure efficiently, the highly complex nature of native riparian forests can result in highly uncertain estimates of biomass due to differences in composition (e.g., species richness, age class) and structure (e.g., stem density). This study presents the comparative results of standing carbon estimates refined with field data collected by citizen scientists at three different sites, each capturing a range of agricultural, remnant forest, and restored forest cover types. These citizen science data resolve uncertainty in composition and structure, and improve allometric scaling models of biomass and thus estimates of aboveground carbon. Results indicate that agricultural land and horticulturally restored riparian forests store similar amounts of aboveground carbon (< 50 Mg/ha), but significantly less than naturally recruiting riparian forests (50 - 200 Mg/ha). Monitoring and assessment of dynamic ecosystem processes and functions will increasingly use data intensive methodologies; however, this research shows the utility of engaging citizen scientists in developing more robust data streams that not only reduces uncertainty, but also provide invaluable opportunities for improved education and outreach.
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NASA Astrophysics Data System (ADS)
Odeh, I. A.; Zou, X. L.
2015-12-01
In terms of total terrestrial sequestered carbon, the global soils and forests are recognized as the predominant C sinks. Even though urban forests stored a relatively small proportion of the total terrestrial C, they also provide other important ecosystem services such as improving air quality, cooling effect in buildings and aesthetics. Thus in view of these environmental services the quantification of urban tree is increasingly viewed as essential to the understanding of how these ecosystem services can be optimized. The aims of this paper are to: i) quantify the spatial-temporal distribution of urban forests in Northwest Sydney using remote sensing techniques; ii) determine the total urban C-storage over many decades; iii) apply UFORE model to estimate air pollutant removal ability of urban forest. The results revealed the estimated total trees in Northwest Sydney in 2011was approximately 2.3 million. These urban forests potentially store an estimated 1.3 million tons of carbon in various forms such as biomass, soil carbon, etc. The relative carbon sequestration rate of these trees was estimated to be about 20,500 tC/yr (equivalent to AUD 467,000/year). Furthermore, the results show that trees near buildings can potentially avoid AUD 12.9 million of energy cost every year and 70000 tons of carbon emission, the latter which is equivalent to additional savings of nearly AUD 1.6 million per year. We also estimated that urban forests in the study area could potentially remove about 44,600 tons of pollutants (mainly greenhouse gases) annually equivalent to a saving of about AUD 409 million per year. Thus the results reveal the spatial-temporal variation of urban vegetation in the last twenty year between 1991 and 2011. The study has showcased the importance and potential role of urban forests in preserving carbon and thus reducing GHG emissions into atmosphere. Furthermore, these results highlight the significant value of urban forests in term of pollutant removal. The significance of these outcomes, if extrapolated to other cities of Australia and the world, is huge.
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Kwon, Sae Yun; Blum, Joel D; Nadelhoffer, Knute J; Timothy Dvonch, J; Tsui, Martin Tsz-Ki
2015-11-01
Studies of monomethylmercury (MMHg) sources and biogeochemical pathways have been extensive in aquatic ecosystems, but limited in forest ecosystems. Increasing evidence suggests that there is significant mercury (Hg) exchange between aquatic and forest ecosystems. We use Hg stable isotope ratios (δ(202)Hg and Δ(199)Hg) to investigate the relative importance of MMHg sources and assess Hg transfer pathways between Douglas Lake and adjacent forests located at the University of Michigan Biological Station, USA. We characterize Hg isotopic compositions of basal resources and use linear regression of % MMHg versus δ(202)Hg and Δ(199)Hg to estimate Hg isotope values for inorganic mercury (IHg) and MMHg in the aquatic and adjacent forest food webs. In the aquatic ecosystem, we found that lake sediment represents a mixture of IHg pools deposited via watershed runoff and precipitation. The δ(202)Hg and Δ(199)Hg values estimated for IHg are consistent with other studies that measured forest floor in temperate forests. The Δ(199)Hg value estimated for MMHg in the aquatic food web indicates that MMHg is subjected to ~20% photochemical degradation prior to bioaccumulation. In the forest ecosystem, we found a significant negative relationship between total Hg and δ(202)Hg and Δ(199)Hg of soil collected at multiple distances from the lakeshore and lake sediment. This suggests that IHg input from watershed runoff provides an important Hg transfer pathway between the forest and aquatic ecosystems. We measured Δ(199)Hg values for high trophic level insects and compared these insects at multiple distances perpendicular to the lake shoreline. The Δ(199)Hg values correspond to the % canopy cover suggesting that forest MMHg is subjected to varying extents of photochemical degradation and the extent may be controlled by sunlight. Our study demonstrates that the use of Hg isotopes adds important new insight into the relative importance of MMHg sources and complex Hg transfer pathways across ecosystem boundaries. Copyright © 2015 Elsevier B.V. All rights reserved.
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NASA Astrophysics Data System (ADS)
Nagendra, U.; Peterson, C.
2013-12-01
Forest disturbances such as tornadoes are expected to raise soil temperatures and increase soil respiration. Opening canopy gaps allows solar radiation to heat the forest floor, and damaged plant roots provide fuel for decomposition. Patches of disturbed forest can range from low severity (some defoliation, broken branches) to high severity (uprooted or snapped trees). Disturbance severity affects plant population and community processes, such as regeneration mode, species diversity, and community structure. We expect disturbance severity to also affect ecosystem processes such as soil respiration. Severe disturbances cause more distinct, and often larger, canopy gaps than mild disturbances, and damage more standing biomass, both above- and below-ground. We would expect these larger gaps and greater litter amounts to increase soil temperature and respiration in more severely disturbed forest patches. In April 2011, a moderate (EF-3) tornado damaged portions of the Chattahoochee National Forest in NE Georgia, USA. Our lab has been characterizing the damage and regeneration in sections of the forest since summer 2011. In Spring 2013, we installed 4 iButton temperature sensors in each of 14 plots across a range of disturbance severity (for a total of 56 sensors). Severity was determined by percent of initial tree basal area downed by the tornado, and ranged from 8% to 100% basal area down. The iButtons monitored soil temperature at a depth of 5 cm every hour for 85 days. In July 2013, integrated 24-hour soil respiration was measured at the same locations using soda lime absorption in sealed PVC collars. Soil temperature at 5 cm averaged 12.66 °C. Contrary to expectations, average daily temperatures did not increase with greater plot damage severity (R2 = 0.001). Daily variation was only slightly higher in plots of very high severity. Overall, soil temperatures appeared to have returned to pre-disturbance temperatures more quickly than expected. Results for upcoming months will be presented at the meeting. Soil respiration was relatively high in all plots (4.49 +/-1.19 g C m-2 hr-1). Contrary to expectations, respiration did not vary significantly with plot damage severity (R2 = 0.0676). The temperature and respiration data together suggest potentially rapid ecosystem recovery after these types of wind disturbances. The flush of understory growth in open patches may insulate the forest floor from solar radiation, even though the forest canopy is still open. These unexpected preliminary results may indicate that ecosystem processes in southern forests are more resilient to disturbances than previously thought. Although forests become carbon sinks immediately after disturbances, they may return to carbon neutral or sink status relatively quickly, given the right circumstances.
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A Practical Decision-Analysis Process for Forest Ecosystem Management
H. Michael Rauscher; F. Thomas Lloyd; David L. Loftis; Mark J. Twery
2000-01-01
Many authors have pointed out the need to firm up the 'fuzzy' ecosystem management paradigm and develop operationally practical processes to allow forest managers to accommodate more effectively the continuing rapid change in societal perspectives and goals. There are three spatial scales where clear, precise, practical ecosystem management processes are...
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Forests planted for ecosystem restoration or conservation.
Constance A. Harrington
1999-01-01
Although the phrase, "planting for ecosystem restoration," is of recent origin, many of the earliest large-scale tree plantings were made for what we now refer to as "'restoration" or "conservation" goals. Forest restoration activities may be needed when ecosystems are disturbed by either natural or anthropogenic forces. Disturbances...
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Carpathian mountain forest vegetation and its responses to climate stressors
NASA Astrophysics Data System (ADS)
Zoran, Maria A.; Savastru, Roxana S.; Savastru, Dan M.; Tautan, Marina N.; Baschir, Laurentiu V.; Dida, Adrian I.
2017-10-01
Due to anthropogenic and climatic changes, Carpathian Mountains forests in Romania experience environmental degradation. As a result of global climate change, there is growing evidence that some of the most severe weather events could become more frequent in Romania over the next 50 to 100 years. In the case of Carpathian mountain forests, winter storms and heat waves are considered key climate risks, particularly in prealpine and alpine areas. Effects of climate extremes on forests can have both short-term and long-term implications for standing biomass, tree health and species composition. The preservation and enhancement of mountain forest vegetation cover in natural, semi-natural forestry ecosystems is an essential factor in sustaining environmental health and averting natural hazards. This paper aims to: (i) describe observed trends and scenarios for summer heat waves, windstorms and heavy precipitation, based on results from satellite time series NOAA AVHRR, MODIS Terra/Aqua and Landsat TM/ETM+/OLI NDVI and LAI data recorded during 2000-2016 period correlated with meteorological parameters, regional climate models, and other downscaling procedures, and (ii) discuss potential impacts of climate changes and extreme events on Carpathian mountain forest system in Romania. The response of forest land cover vegetation in Carpathian Mountains, Romania to climatic factors varies in different seasons of the years, the diverse vegetation feedbacks to climate changes being related to different vegetation characteristics and meteorological conditions. Based on integrated analysis of satellite and field data was concluded that forest ecosystem functions are responsible of the relationships between mountain specific vegetation and climate.
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Mathias, Justin M; Thomas, Richard B
2018-05-20
In the 45 years after legislation of the Clean Air Act, there has been tremendous progress in reducing acidic air pollutants in the eastern United States, yet limited evidence exists that cleaner air has improved forest health. Here, we investigate the influence of recent environmental changes on the growth and physiology of red spruce (Picea rubens Sarg.) trees, a key indicator species of forest health, spanning three locations along a 100 km transect in the Central Appalachian Mountains. We incorporated a multiproxy approach using 75-year tree ring chronologies of basal tree growth, carbon isotope discrimination (∆ 13 C, a proxy for leaf gas exchange), and δ 15 N (a proxy for ecosystem N status) to examine tree and ecosystem level responses to environmental change. Results reveal the two most important factors driving increased tree growth since ca. 1989 are reductions in acidic sulfur pollution and increases in atmospheric CO 2 , while reductions in pollutant emissions of NO x and warmer springs played smaller, but significant roles. Tree ring ∆ 13 C signatures increased significantly since 1989, concurrently with significant declines in tree ring δ 15 N signatures. These isotope chronologies provide strong evidence that simultaneous changes in C and N cycling, including greater photosynthesis and stomatal conductance of trees and increases in ecosystem N retention, were related to recent increases in red spruce tree growth and are consequential to ecosystem recovery from acidic pollution. Intrinsic water use efficiency (iWUE) of the red spruce trees increased by ~51% across the 75-year chronology, and was driven by changes in atmospheric CO 2 and acid pollution, but iWUE was not linked to recent increases in tree growth. This study documents the complex environmental interactions that have contributed to the recovery of red spruce forest ecosystems from pervasive acidic air pollution beginning in 1989, about 15 years after acidic pollutants started to decline in the United States. © 2018 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.
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Toral Patel-Weynand
2012-01-01
Scientific literature on the effects of climatic variability and change on forest ecosystems has increased significantly over the past decade, providing a foundation for establishing forest-climate relationships and projecting the effects of continued warming on a wide range of forest resources and ecosystem services. In addition, certainty about the nature of some of...
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Improving scientific knowledge
James M. Vose; David L. Peterson
2012-01-01
Scientific literature on the effects of climatic variability and change on forest ecosystems has increased significantly over the past decade, providing a foundation for establishing forest-climate relationships and projecting the effects of continued warming on a wide range of forest resources and ecosystem services. In addition, certainty about the nature of some of...
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Forecasting Urban Forest Ecosystem Structure, Function, and Vulnerability
James W. N. Steenberg; Andrew A. Millward; David J. Nowak; Pamela J. Robinson; Alexis Ellis
2016-01-01
The benefits derived from urban forest ecosystems are garnering increasing attention in ecological research and municipal planning. However, because of their location in heterogeneous and highly-altered urban landscapes, urban forests are vulnerable and commonly suffer disproportionate and varying levels of stress and disturbance. The objective of this study is to...
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Applications of satellite remote sensing to forested ecosystems
Louis R. Iverson; Robin Lambert Graham; Elizabeth A. Cook; Elizabeth A. Cook
1989-01-01
Since the launch of the first civilian earth-observing satellite in 1972, satellite remote sensing has provided increasingly sophisticated information on the structure and function of forested ecosystems. Forest classification and mapping, common uses of satellite data, have improved over the years as a result of more discriminating sensors, better classification...
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Research agenda for integrated landscape modeling
Samuel A. Cushman; Donald McKenzie; David L. Peterson; Jeremy Littell; Kevin S. McKelvey
2007-01-01
Reliable predictions of how changing climate and disturbance regimes will affect forest ecosystems are crucial for effective forest management. Current fire and climate research in forest ecosystem and community ecology offers data and methods that can inform such predictions. However, research in these fields occurs at different scales, with disparate goals, methods,...
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Research agenda for integrated landscape modeling
Samuel A. Cushman; Donald McKenzie; David L. Peterson; Jeremy Littell; Kevin S. McKelvey
2006-01-01
Reliable predictions of the effects changing climate and disturbance regimes will have on forest ecosystems are crucial for effective forest management. Current fire and climate research in forest ecosystem and community ecology offers data and methods that can inform such predictions. However, research in these fields occurs at different scales, with disparate goals,...
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Diversity-dependent temporal divergence of ecosystem functioning in experimental ecosystems.
Guerrero-Ramírez, Nathaly R; Craven, Dylan; Reich, Peter B; Ewel, John J; Isbell, Forest; Koricheva, Julia; Parrotta, John A; Auge, Harald; Erickson, Heather E; Forrester, David I; Hector, Andy; Joshi, Jasmin; Montagnini, Florencia; Palmborg, Cecilia; Piotto, Daniel; Potvin, Catherine; Roscher, Christiane; van Ruijven, Jasper; Tilman, David; Wilsey, Brian; Eisenhauer, Nico
2017-11-01
The effects of biodiversity on ecosystem functioning generally increase over time, but the underlying processes remain unclear. Using 26 long-term grassland and forest experimental ecosystems, we demonstrate that biodiversity-ecosystem functioning relationships strengthen mainly by greater increases in functioning in high-diversity communities in grasslands and forests. In grasslands, biodiversity effects also strengthen due to decreases in functioning in low-diversity communities. Contrasting trends across grasslands are associated with differences in soil characteristics.
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Shuhua Yi; A. David McGuire; Eric Kasischke; Jennifer Harden; Kristen Manies; Michelle Mack; Merritt Turetsky
2010-01-01
Ecosystem models have not comprehensively considered how interactions among fire disturbance, soil environmental conditions, and biogeochemical processes affect ecosystem dynamics in boreal forest ecosystems. In this study, we implemented a dynamic organic soil structure in the Terrestrial Ecosystem Model (DOS-TEM) to investigate the effects of fire on soil temperature...
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David P. Turner; William D. Ritts; Zhiqiang Yang; Robert E. Kennedy; Warren B. Cohen; Maureen V. Duane; Peter E. Thornton; Beverly E. Law
2011-01-01
Carbon sequestration is increasingly recognized as an ecosystem service, and forest management has a large potential to alter regional carbon fluxes, notably by way of harvest removals and related impacts on net ecosystem production (NEP). In the Pacific Northwest region of the US, the implementation of the Northwest Forest Plan (NWFP) in 1993 established a regional...
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Ant diversity in Brazilian tropical dry forests across multiple vegetation domains
NASA Astrophysics Data System (ADS)
Figueiredo Silva, Luciana; Mello Souza, Rayana; Solar, Ricardo R. C.; de Siqueira Neves, Frederico
2017-03-01
Understanding the environmental drivers of biodiversity persistence and community organization in natural ecosystems is of great importance for planning the conservation of those ecosystems. This comprehension is even more important in severely threatened ecosystems. In this context, we analyzed ant communities in tropical dry forests (TDFs) in Brazil. These forests are embedded within other biomes, such as Cerrado and Caatinga. In this study, we asked whether (i) ant species richness and composition changes between TDFs within different vegetation domains; (ii) whether ant species richness and β-diversity increase north-to-south, possibly related to changes in tree richness and tree density; and (iii) species replacement contributes relatively more to β-diversity than does nestedness. We found that species composition is unique to each TDF within different biomes, and that species richness and β-diversity differ among the vegetation domains, being smaller in the Caatinga. We also found that replacement contributes most to β-diversity, although this contribution is lower in Caatinga than in Cerrado. We show that regional context is the main driver of species diversity, which is likely to be driven by both historical and ecological mechanisms. By analyzing large spatial scale variation in TDF environmental characteristics, we were able to evaluate how ant diversity changes along an environmental gradient. The high levels of species replacement and unique species composition of each region indicates that, to fully conserve TDFs, we need to have various conservation areas distributed across the entire range of vegetation domains in which these forests can be found. Thus, we demonstrate that a landscape-wise planning is urgent and necessary in order to preserve tropical dry forests.
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NASA Astrophysics Data System (ADS)
Saarinen, N.; Vastaranta, M.; Näsi, R.; Rosnell, T.; Hakala, T.; Honkavaara, E.; Wulder, M. A.; Luoma, V.; Tommaselli, A. M. G.; Imai, N. N.; Ribeiro, E. A. W.; Guimarães, R. B.; Holopainen, M.; Hyyppä, J.
2017-10-01
Biodiversity is commonly referred to as species diversity but in forest ecosystems variability in structural and functional characteristics can also be treated as measures of biodiversity. Small unmanned aerial vehicles (UAVs) provide a means for characterizing forest ecosystem with high spatial resolution, permitting measuring physical characteristics of a forest ecosystem from a viewpoint of biodiversity. The objective of this study is to examine the applicability of photogrammetric point clouds and hyperspectral imaging acquired with a small UAV helicopter in mapping biodiversity indicators, such as structural complexity as well as the amount of deciduous and dead trees at plot level in southern boreal forests. Standard deviation of tree heights within a sample plot, used as a proxy for structural complexity, was the most accurately derived biodiversity indicator resulting in a mean error of 0.5 m, with a standard deviation of 0.9 m. The volume predictions for deciduous and dead trees were underestimated by 32.4 m3/ha and 1.7 m3/ha, respectively, with standard deviation of 50.2 m3/ha for deciduous and 3.2 m3/ha for dead trees. The spectral features describing brightness (i.e. higher reflectance values) were prevailing in feature selection but several wavelengths were represented. Thus, it can be concluded that structural complexity can be predicted reliably but at the same time can be expected to be underestimated with photogrammetric point clouds obtained with a small UAV. Additionally, plot-level volume of dead trees can be predicted with small mean error whereas identifying deciduous species was more challenging at plot level.