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Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Randomization Tests For Quantifying Species Importance To Ecosystem Function, Nicholas J. Gotelli, Werner Ulrich, Fernando T. Maestre Dec 2011

Randomization Tests For Quantifying Species Importance To Ecosystem Function, Nicholas J. Gotelli, Werner Ulrich, Fernando T. Maestre

College of Arts and Sciences Faculty Publications

1. Quantifying the contribution of different species to ecosystem function is an important challenge. We introduce simple randomization tests (and software) for quantifying the average effect of species on ecosystem variables measured in multiple plots with and without the presence of a particular species. These randomization tests formalize the analysis of uncontrolled 'natural experiments' and quantify species effects in standardized deviation units. 2.We tested the method with data on ecosystem function in biological soil crust assemblages of lichens in semi-arid gypsum outcrops in central Spain. In sixty-three 50cm×50cm sample plots, we measured the presence and percentage cover of 17 species …


Underestimating The Costs Of Conservation In Southeast Asia, David P. Edwards, Brendan Fisher, Xingli Giam, David S. Wilcove Dec 2011

Underestimating The Costs Of Conservation In Southeast Asia, David P. Edwards, Brendan Fisher, Xingli Giam, David S. Wilcove

Rubenstein School of Environment and Natural Resources Faculty Publications

No abstract provided.


The Limits To Prediction In Ecological Systems, Brian Beckage, Louis J. Gross, Stuart Kauffman Nov 2011

The Limits To Prediction In Ecological Systems, Brian Beckage, Louis J. Gross, Stuart Kauffman

College of Agriculture and Life Sciences Faculty Publications

Predicting the future trajectories of ecological systems is increasingly important as the magnitude of anthropogenic perturbation of the earth systems grows.We distinguish between two types of predictability: the intrinsic or theoretical predictability of a system and the realized predictability that is achieved using available models and parameterizations. We contend that there are strong limits on the intrinsic predictability of ecological systems that arise from inherent characteristics of biological systems. While the realized predictability of ecological systems can be limited by process and parameter misspecification or uncertainty, we argue that the intrinsic predictability of ecological systems is widely and strongly limited …


Heating Up The Forest: Open-Top Chamber Warming Manipulation Of Arthropod Communities At Harvard And Duke Forests, Shannon L. Pelini, Francis P. Bowles, Aaron M. Ellison, Nicholas J. Gotelli, Nathan J. Sanders, Robert R. Dunn Oct 2011

Heating Up The Forest: Open-Top Chamber Warming Manipulation Of Arthropod Communities At Harvard And Duke Forests, Shannon L. Pelini, Francis P. Bowles, Aaron M. Ellison, Nicholas J. Gotelli, Nathan J. Sanders, Robert R. Dunn

College of Arts and Sciences Faculty Publications

1.Recent observations indicate that climatic change is altering biodiversity, and models suggest that the consequences of climate change will differ across latitude. However, long-term experimental field manipulations that directly test the predictions about organisms' responses to climate change across latitude are lacking. Such experiments could provide a more mechanistic understanding of the consequences of climate change on ecological communities and subsequent changes in ecosystem processes, facilitating better predictions of the effects of future climate change. 2.This field experiment uses octagonal, 5-m-diameter (c.22m 3) open-top chambers to simulate warming at northern (Harvard Forest, Massachusetts) and southern (Duke Forest, North Carolina) hardwood …


A Natural-Resource-Based View Of The Firm: Fifteen Years After, Stuart L. Hart, Glen Dowell Sep 2011

A Natural-Resource-Based View Of The Firm: Fifteen Years After, Stuart L. Hart, Glen Dowell

Grossman School of Business Faculty Publications

The authors revisit Hart's natural-resource-based view (NRBV) of the firm and summarize progress that has been made in testing elements of that theory and reevaluate the NRBV in light of a number of important developments that have emerged in recent years in both the resource-based view literature and in research on sustainable enterprise. First, the authors consider how the NRBV can both benefit from recent work in dynamic capabilities and can itself inform such work. Second, they review recent research in the areas of clean technology and business at the base of the pyramid and suggest how the NRBV can …


Understanding Earth's Eroding Surface With 10Be, Eric W. Portenga, Paul R. Bierman Aug 2011

Understanding Earth's Eroding Surface With 10Be, Eric W. Portenga, Paul R. Bierman

College of Arts and Sciences Faculty Publications

For more than a century, geologists have sought to measure the distribution of erosion rates on Earth's dynamic surface. Since the mid-1980s, measurements of in situ 10Be, a cosmogenic radionuclide, have been used to estimate outcrop and basin-scale erosion rates at 87 sites around the world. Here, we compile, normalize, and compare published 10Be erosion rate data (n = 1599) in order to understand how, on a globalscale, geologic erosion rates integrated over 103 to 106 years varybetween climate zones, tectonic settings, and different rock types. Drainage basins erodemore quickly (mean = 218 m Myr-1; median = 54 m Myr-1) …


The Effects Of Climate Change On Density-Dependent Population Dynamics Of Aquatic Invertebrates, Edmund M. Hart, Nicholas J. Gotelli Aug 2011

The Effects Of Climate Change On Density-Dependent Population Dynamics Of Aquatic Invertebrates, Edmund M. Hart, Nicholas J. Gotelli

College of Arts and Sciences Faculty Publications

Global climate change has the potential to alter aquatic communities through changes in evapotranspiration and increased variability in precipitation. We used aquatic mesocosms to test the impacts of variable precipitation on population dynamics of commonn mosquito (Culicidae) and midge (Chironomidae) larvae that inhabit vernal pools. In a mixed deciduous forest in northern Vermont, USA, we orthogonally crossed seven levels of mean water level (increased rainfall) with seven levels of water level coefficient of variation (more variable rainfall) to simulate a broad array of climate change scenarios in 49 experimental mesocosms. The average abundance of Culicidae was highest at low water …


The High Costs Of Conserving Southeast Asia's Lowland Rainforests, Brendan Fisher, David P. Edwards, Xingli Giam, David S. Wilcove Aug 2011

The High Costs Of Conserving Southeast Asia's Lowland Rainforests, Brendan Fisher, David P. Edwards, Xingli Giam, David S. Wilcove

Rubenstein School of Environment and Natural Resources Faculty Publications

Mechanisms that mitigate greenhouse-gas emissions via forest conservation have been portrayed as a cost-effective approach that can also protect biodiversity and vital ecosystem services. However, the costs of conservation - including opportunity costs - are spatially heterogeneous across the globe. The lowland rainforests of Southeast Asia represent a unique nexus of large carbon stores, imperiled biodiversity, large stores of timber, and high potential for conversion to oil-palm plantations, making this region one where understanding the costs of conservation is critical. Previous studies have underestimated the gap between conservation costs and conversion benefits in Southeast Asia. Using detailed logging records, cost …


Evaluating The Remote Sensing And Inventory-Based Estimation Of Biomass In The Western Carpathians, Magdalena Main-Knorn, Gretchen G. Moisen, Sean P. Healey, William S. Keeton, Elizabeth A. Freeman, Patrick Hostert Jul 2011

Evaluating The Remote Sensing And Inventory-Based Estimation Of Biomass In The Western Carpathians, Magdalena Main-Knorn, Gretchen G. Moisen, Sean P. Healey, William S. Keeton, Elizabeth A. Freeman, Patrick Hostert

Rubenstein School of Environment and Natural Resources Faculty Publications

Understanding the potential of forest ecosystems as global carbon sinks requires a thorough knowledge of forest carbon dynamics, including both sequestration and fluxes among multiple pools. The accurate quantification of biomass is important to better understand forest productivity and carbon cycling dynamics. Stand-based inventories (SBIs) are widely used for quantifying forest characteristics and for estimating biomass, but information may quickly become outdated in dynamic forest environments. Satellite remote sensing may provide a supplement or substitute. We tested the accuracy of aboveground biomass estimates modeled from a combination of Landsat Thematic Mapper (TM) imagery and topographic data, as well as SBI-derived …


Effects Of Short-Term Warming On Low And High Latitude Forest Ant Communities, Shannon L. Pelini, Mark Boudreau, Neil Mccoy, Aaron M. Ellison, Nicholas J. Gotelli, Nathan J. Sanders, Robert R. Dunn May 2011

Effects Of Short-Term Warming On Low And High Latitude Forest Ant Communities, Shannon L. Pelini, Mark Boudreau, Neil Mccoy, Aaron M. Ellison, Nicholas J. Gotelli, Nathan J. Sanders, Robert R. Dunn

College of Arts and Sciences Faculty Publications

Climatic change is expected to have differential effects on ecological communities in different geographic areas. However, few studies have experimentally demonstrated the effects of warming on communities simultaneously at different locales. We manipulated air temperature with in situ passive warming and cooling chambers and quantified effects of temperature on ant abundance, diversity, and foraging activities (predation, scavenging, seed dispersal, nectivory, granivory) in two deciduous forests at 35° and 43° N latitude in the eastern U.S. In the southern site, the most abundant species, Crematogaster lineolata, increased while species evenness, most ant foraging activities, and abundance of several other ant species …


Counting Ants (Hymenoptera: Formicidae): Biodiversity Sampling And Statistical Analysis For Myrmecologists, Nicholas J. Gotelli, Aaron M. Ellison, Robert R. Dunn, Nathan J. Sanders May 2011

Counting Ants (Hymenoptera: Formicidae): Biodiversity Sampling And Statistical Analysis For Myrmecologists, Nicholas J. Gotelli, Aaron M. Ellison, Robert R. Dunn, Nathan J. Sanders

College of Arts and Sciences Faculty Publications

Biodiversity sampling is labor intensive and is especially challenging for myrmecologists, because the sampling units (individual workers) do not correspond in a simple way to the natural units of diversity (individual nests). Because it is usually not possible to reach a sampling asymptote for ants, comparisons of species richness among collections have to be carefully standardized for the number of individuals and number of samples examined. Asymptotic estimators allow for extrapolation to an estimated asymptote of species richness, and rarefaction curves permit meaningful comparisons of samples by interpolating data to a standardized number of sampling units. Winkler sacks of leaf …


Historical Carbon Emissions And Uptake From The Agricultural Frontier Of The Brazilian Amazon, Gillian L. Galford, Jerry M. Melillo, David W. Kicklighter, John F. Mustard, Timothy W. Cronin, Carlos E.P. Cerri, Carlos C. Cerri Apr 2011

Historical Carbon Emissions And Uptake From The Agricultural Frontier Of The Brazilian Amazon, Gillian L. Galford, Jerry M. Melillo, David W. Kicklighter, John F. Mustard, Timothy W. Cronin, Carlos E.P. Cerri, Carlos C. Cerri

Rubenstein School of Environment and Natural Resources Faculty Publications

Tropical ecosystems play a large and complex role in the global carbon cycle. Clearing of natural ecosystems for agriculture leads to large pulses of CO2 to the atmosphere from terrestrial biomass. Concurrently, the remaining intact ecosystems, especially tropical forests, may be sequestering a large amount of carbon from the atmosphere in response to global environmental changes including climate changes and an increase in atmospheric CO2 Here we use an approach that integrates census-based historical land use reconstructions, remote-sensing-based contemporary land use change analyses, and simulation modeling of terrestrial biogeochemistry to estimate the net carbon balance over the period 1901-2006 for …


Incorporating Systems Thinking And Sustainability Within Civil And Environmental Engineering Curricula At Uvm, Nancy J. Hayden, Donna M. Rizzo, Mandar M. Dewoolkar, Lalita Oka, Maureen Neumann Jan 2011

Incorporating Systems Thinking And Sustainability Within Civil And Environmental Engineering Curricula At Uvm, Nancy J. Hayden, Donna M. Rizzo, Mandar M. Dewoolkar, Lalita Oka, Maureen Neumann

College of Engineering and Mathematical Sciences Faculty Publications

As part of an NSF Department Level Reform (DLR) grant, the civil and environmental engineering programs at the University of Vermont (UVM) incorporated systems thinking and a systems approach to engineering problem solving within their programs. A systems thinking approach regards social, environmental and economic factors as necessary components of the problem solution. Because it is a whole systems approach it also encompasses sustainability. We have integrated systems thinking in the following ways; 1) new material has been included into key courses (e.g. the first-year introductory and senior design courses), 2) a sequence of three related environmental and transportation systems …


Cost-Effective Conservation: Calculating Biodiversity And Logging Trade-Offs In Southeast Asia, Brendan Fisher, David P. Edwards, Trond H. Larsen, Felicity A. Ansell, Wayne W. Hsu, Carter S. Roberts, David S. Wilcove Jan 2011

Cost-Effective Conservation: Calculating Biodiversity And Logging Trade-Offs In Southeast Asia, Brendan Fisher, David P. Edwards, Trond H. Larsen, Felicity A. Ansell, Wayne W. Hsu, Carter S. Roberts, David S. Wilcove

Rubenstein School of Environment and Natural Resources Faculty Publications

The Sundaland Biodiversity Hotspot of Southeast Asia is widely regarded as one of the most imperiled biodiversity hotspots due to high degrees of endemism coupled with extensive logging and forest conversion to oil palm. The large financial returns to these activities have made it difficult to conserve much of the region's lowland primary forest, suggesting a large trade-off between economic interests and biodiversity conservation. Here, we provide an empirical examination of the magnitude of this trade-off in Borneo. By incorporating both financial values and biodiversity responses across logging regimes, we show that selectively logged forests represent a surprisingly low-cost option …


Cross-Scale Value Trade-Offs In Managing Social-Ecological Systems: The Politics Of Scale In Ruaha National Park, Tanzania, Asim Zia, Paul Hirsch, Alexander Songorwa, David R. Mutekanga, Sheila O'Connor, Thomas Mcshane, Peter Brosius, Bryan Norton Jan 2011

Cross-Scale Value Trade-Offs In Managing Social-Ecological Systems: The Politics Of Scale In Ruaha National Park, Tanzania, Asim Zia, Paul Hirsch, Alexander Songorwa, David R. Mutekanga, Sheila O'Connor, Thomas Mcshane, Peter Brosius, Bryan Norton

College of Agriculture and Life Sciences Faculty Publications

Management of social-ecological systems takes place amidst complex governance processes and cross-scale institutional arrangements that are mediated through politics of scale. Each management scenario generates distinct cross-scale trade-offs in the distribution of pluralistic values. This study explores the hypothesis that conservation-oriented management scenarios generate higher value for international and national scale social organizations, whereas mixed or more balanced management scenarios generate higher value for local scale social organizations. This hypothesis is explored in the management context of Ruaha National Park (RNP), Tanzania, especially the 2006 expansion of RNP that led to the eviction of many pastoralists and farmers. Five management …