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Ancient Amazonian Populations Left Lasting Impacts On Forest Structure, Michael W. Palace, C. N. H. Mcmichael, Bobby H. Braswell, S. C. Hagen, M. B. Bush, E. Neves, E. Tamanaha, Christina Herrick, Stephen E. Frolking Dec 2017

Ancient Amazonian Populations Left Lasting Impacts On Forest Structure, Michael W. Palace, C. N. H. Mcmichael, Bobby H. Braswell, S. C. Hagen, M. B. Bush, E. Neves, E. Tamanaha, Christina Herrick, Stephen E. Frolking

Earth Systems Research Center

Amazonia contains a vast expanse of contiguous tropical forest and is influential in global carbon and hydrological cycles. Whether ancient Amazonia was highly disturbed or modestly impacted, and how ancient disturbances have shaped current forest ecosystem processes, is still under debate. Amazonian Dark Earths (ADEs), which are anthropic soil types with enriched nutrient levels, are one of the primary lines of evidence for ancient human presence and landscape modifications in settings that mostly lack stone structures and which are today covered by vegetation. We assessed the potential of using moderate spatial resolution optical satellite imagery to predict ADEs across the …


Approaches For Advancing Scientific Understanding Of Macrosystems, Ofir Levy, Becky A. Ball, Ben Bond-Lamberty, Kendra S. Cheruvelil, Andrew O. Finley, Noah R. Lottig, Surangi W. Punyasena, Jingfeng Xiao, Jizhong Zhou, Lauren B. Buckley, Christopher T. Filstrup, Tim H. Keitt, James R. Kellner, Alan K. Knapp, Andrew D. Richardson, David Tcheng, Michael Toomey, Rodrigo Vargas, James W. Voordeckers, Tyler Wagner Aug 2017

Approaches For Advancing Scientific Understanding Of Macrosystems, Ofir Levy, Becky A. Ball, Ben Bond-Lamberty, Kendra S. Cheruvelil, Andrew O. Finley, Noah R. Lottig, Surangi W. Punyasena, Jingfeng Xiao, Jizhong Zhou, Lauren B. Buckley, Christopher T. Filstrup, Tim H. Keitt, James R. Kellner, Alan K. Knapp, Andrew D. Richardson, David Tcheng, Michael Toomey, Rodrigo Vargas, James W. Voordeckers, Tyler Wagner

Earth Systems Research Center

The emergence of macrosystems ecology (MSE), which focuses on regional- to continental-scale ecological patterns and processes, builds upon a history of long-term and broad-scale studies in ecology. Scientists face the difficulty of integrating the many elements that make up macrosystems, which consist of hierarchical processes at interacting spatial and temporal scales. Researchers must also identify the most relevant scales and variables to be considered, the required data resources, and the appropriate study design to provide the proper inferences. The large volumes of multi-thematic data often associated with macrosystem studies typically require validation, standardization, and assimilation. Finally, analytical approaches need to …


Tradeoffs Between Three Forest Ecosystem Services Across The State Of New Hampshire, Usa: Timber, Carbon, And Albedo, David A. Lutz, Elizabeth A. Burakowski, Mackenzie B. Murphy, Mark E. Borsuk, Rebecca M. Niemiec, Richard B. Howarth Jan 2016

Tradeoffs Between Three Forest Ecosystem Services Across The State Of New Hampshire, Usa: Timber, Carbon, And Albedo, David A. Lutz, Elizabeth A. Burakowski, Mackenzie B. Murphy, Mark E. Borsuk, Rebecca M. Niemiec, Richard B. Howarth

Earth Systems Research Center

Forests are more frequently being managed to store and sequester carbon for the purposes of climate change mitigation. Generally, this practice involves long-term conservation of intact mature forests and/or reductions in the frequency and intensity of timber harvests. However, incorporating the influence of forest surface albedo often suggests that long rotation lengths may not always be optimal in mitigating climate change in forests characterized by frequent snowfall. To address this, we investigated trade-offs between three ecosystem services: carbon storage, albedo-related radiative forcing, and timber provisioning. We calculated optimal rotation length at 498 diverse Forest Inventory and Analysis forest sites in …


Global Patterns, Trends, And Drivers Of Water Use Efficiency From 2000 To 2013, Bao-Lin Xue, Qinghua Guo, Alvarez Otto, Jingfeng Xiao, Shengli Tao, Le Li Oct 2015

Global Patterns, Trends, And Drivers Of Water Use Efficiency From 2000 To 2013, Bao-Lin Xue, Qinghua Guo, Alvarez Otto, Jingfeng Xiao, Shengli Tao, Le Li

Earth Systems Research Center

Water use efficiency (WUE; gross primary production [GPP]/evapotranspiration [ET]) estimates the tradeoff between carbon gain and water loss during photosynthesis and is an important link of the carbon and water cycles. Understanding the spatiotemporal patterns and drivers of WUE is helpful for projecting the responses of ecosystems to climate change. Here we examine the spatiotemporal patterns, trends, and drivers of WUE at the global scale from 2000 to 2013 using the gridded GPP and ET data derived from the Moderate Resolution Imaging Spectroradiometer (MODIS). Our results show that the global WUE has an average value of 1.70 g C/kg H2O …


Water Use Efficiency Of China's Terrestrial Ecosystems And Responses To Drought, Yibo Liu, Jingfeng Xiao, Weimin Ju, Shaoqiang Wang, Xiaocui Wu Sep 2015

Water Use Efficiency Of China's Terrestrial Ecosystems And Responses To Drought, Yibo Liu, Jingfeng Xiao, Weimin Ju, Shaoqiang Wang, Xiaocui Wu

Earth Systems Research Center

Water use efficiency (WUE) measures the trade-off between carbon gain and water loss of terrestrial ecosystems, and better understanding its dynamics and controlling factors is essential for predicting ecosystem responses to climate change. We assessed the magnitude, spatial patterns, and trends of WUE of China’s terrestrial ecosystems and its responses to drought using a process-based ecosystem model. During the period from 2000 to 2011, the national average annual WUE (net primary productivity (NPP)/evapotranspiration (ET)) of China was 0.79 g C kg−1 H2O. Annual WUE decreased in the southern regions because of the decrease in NPP and the increase in ET …


Macrosystems Ecology: Understanding Ecological Patterns And Processes At Continental Scales, James B. Heffernan, Patricia A. Soranno, Michael J. Angilletta Jr., Lauren B. Buckley, Daniel S. Gruner, Tim H. Keitt, James R. Kellner, John S. Kominoski, Adrian V. Rocha, Jingfeng Xiao, Tamara K. Harms, Simon J. Goring, Lauren E. Koenig, William H. Mcdowell, Heather Powell, Andrew D. Richardson, Craig A. Stow, Rodrigo Vargas, Kathleen C. Weathers Feb 2014

Macrosystems Ecology: Understanding Ecological Patterns And Processes At Continental Scales, James B. Heffernan, Patricia A. Soranno, Michael J. Angilletta Jr., Lauren B. Buckley, Daniel S. Gruner, Tim H. Keitt, James R. Kellner, John S. Kominoski, Adrian V. Rocha, Jingfeng Xiao, Tamara K. Harms, Simon J. Goring, Lauren E. Koenig, William H. Mcdowell, Heather Powell, Andrew D. Richardson, Craig A. Stow, Rodrigo Vargas, Kathleen C. Weathers

Earth Systems Research Center

Macrosystems ecology is the study of diverse ecological phenomena at the scale of regions to continents and their interactions with phenomena at other scales. This emerging subdiscipline addresses ecological questions and environmental problems at these broad scales. Here, we describe this new field, show how it relates to modern ecological study, and highlight opportunities that stem from taking a macrosystems perspective. We present a hierarchical framework for investigating macrosystems at any level of ecological organization and in relation to broader and finer scales. Building on well-established theory and concepts from other subdisciplines of ecology, we identify feedbacks, linkages among distant …


A Comparison Of Presettlement And Modern Forest Composition Along An Elevation Gradient In Central New Hampshire, Matthew A. Vadeboncoeur, Steven P. Hamburg, Charles V. Cogbill, Wendy Y. Sugimura Dec 2011

A Comparison Of Presettlement And Modern Forest Composition Along An Elevation Gradient In Central New Hampshire, Matthew A. Vadeboncoeur, Steven P. Hamburg, Charles V. Cogbill, Wendy Y. Sugimura

Earth Systems Research Center

Tree species composition is influenced not only by edaphic and climatic factors but also by natural and human-caused disturbances. To understand interactions among these influences, we compared forest species composition data from the time of European settlement with modern data. We derived elevation data for 2529 trees mapped by early land surveys (1770–1850) across a 1000 m elevation gradient in central New Hampshire and compared these with modern data (2004–2009) from the Forest Inventory and Analysis program (123 plots containing 2126 trees) and from permanent plots representing case studies of different land-use histories. Spruce and beech are much less abundant …