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Full-Text Articles in Physical Sciences and Mathematics

Using Physiology To Predict The Responses Of Ants To Climatic Warming, Sarah E. Diamond, Clint A. Penick, Shannon L. Pelini, Aaron M. Ellison, Nicholas J. Gotelli, Nathan J. Sanders, Robert R. Dunn Dec 2013

Using Physiology To Predict The Responses Of Ants To Climatic Warming, Sarah E. Diamond, Clint A. Penick, Shannon L. Pelini, Aaron M. Ellison, Nicholas J. Gotelli, Nathan J. Sanders, Robert R. Dunn

College of Arts and Sciences Faculty Publications

Physiological intolerance of high temperatures places limits on organismal responses to the temperature increases associated with global climatic change. Because ants are geographically widespread, ecologically diverse, and thermophilic, they are an ideal system for exploring the extent to which physiological tolerance can predict responses to environmental change. Here, we expand on simple models that use thermal tolerance to predict the responses of ants to climatic warming. We investigated the degree to which changes in the abundance of ants under warming reflect reductions in the thermal niche space for their foraging. In an eastern deciduous forest system in the United States …


Coupling Self-Organizing Maps With A Naïve Bayesian Classifier: Stream Classification Studies Using Multiple Assessment Data, Nikolaos Fytilis, Donna M. Rizzo Nov 2013

Coupling Self-Organizing Maps With A Naïve Bayesian Classifier: Stream Classification Studies Using Multiple Assessment Data, Nikolaos Fytilis, Donna M. Rizzo

College of Engineering and Mathematical Sciences Faculty Publications

Organizing or clustering data into natural groups is one of the most fundamental aspects of understanding and mining information. The recent explosion in sensor networks and data storage associated with hydrological monitoring has created a huge potential for automating data analysis and classification of large, high-dimensional data sets. In this work, we develop a new classification tool that couples a Naïve Bayesian classifier with a neural network clustering algorithm (i.e., Kohonen Self-Organizing Map (SOM)). The combined Bayesian-SOM algorithm reduces classification error by leveraging the Bayesian's ability to accommodate parameter uncertainty with the SOM's ability to reduce high-dimensional data to lower …


Beyond Climate-Smart Agriculture: Toward Safe Operating Spaces For Global Food Systems, Henry Neufeldt, Molly Jahn, Bruce M. Campbell, John R. Beddington, Fabrice Declerck, Alessandro De Pinto, Jay Gulledge, Jonathan Hellin, Mario Herrero, Andy Jarvis, David Lezaks, Holger Meinke, Todd Rosenstock, Mary Scholes, Robert Scholes, Sonja Vermeulen, Eva Wollenberg, Robert Zougmoré Aug 2013

Beyond Climate-Smart Agriculture: Toward Safe Operating Spaces For Global Food Systems, Henry Neufeldt, Molly Jahn, Bruce M. Campbell, John R. Beddington, Fabrice Declerck, Alessandro De Pinto, Jay Gulledge, Jonathan Hellin, Mario Herrero, Andy Jarvis, David Lezaks, Holger Meinke, Todd Rosenstock, Mary Scholes, Robert Scholes, Sonja Vermeulen, Eva Wollenberg, Robert Zougmoré

Rubenstein School of Environment and Natural Resources Faculty Publications

Agriculture is considered to be "climate-smart" when it contributes to increasing food security, adaptation and mitigation in a sustainable way. This new concept now dominates current discussions in agricultural development because of its capacity to unite the agendas of the agriculture, development and climate change communities under one brand. In this opinion piece authored by scientists from a variety of international agricultural and climate research communities, we argue that the concept needs to be evaluated critically because the relationship between the three dimensions is poorly understood, such that practically any improved agricultural practice can be considered climate-smart. This lack of …


Payments For Ecosystem Services And The Fatal Attraction Of Win-Win Solutions, R. Muradian, M. Arsel, L. Pellegrini, F. Adaman, B. Aguilar, B. Agarwal, E. Corbera, D. Ezzine De Blas, J. Farley, G. Froger, E. Garcia-Frapolli, E. Gómez-Baggethun, J. Gowdy Jul 2013

Payments For Ecosystem Services And The Fatal Attraction Of Win-Win Solutions, R. Muradian, M. Arsel, L. Pellegrini, F. Adaman, B. Aguilar, B. Agarwal, E. Corbera, D. Ezzine De Blas, J. Farley, G. Froger, E. Garcia-Frapolli, E. Gómez-Baggethun, J. Gowdy

College of Agriculture and Life Sciences Faculty Publications

In this commentary we critically discuss the suitability of payments for ecosystem services and the most important challenges they face. While such instruments can play a role in improving environmental governance, we argue that over-reliance on payments as win-win solutions might lead to ineffective outcomes, similar to earlier experience with integrated conservation and development projects. Our objective is to raise awareness, particularly among policy makers and practitioners, about the limitations of such instruments and to encourage a dialogue about the policy contexts in which they might be appropriate. © 2013 Wiley Periodicals, Inc.


Maxent Versus Maxlike: Empirical Comparisons With Ant Species Distributions, Matthew C. Fitzpatrick, Nicholas J. Gotelli, Aaron M. Ellison May 2013

Maxent Versus Maxlike: Empirical Comparisons With Ant Species Distributions, Matthew C. Fitzpatrick, Nicholas J. Gotelli, Aaron M. Ellison

College of Arts and Sciences Faculty Publications

MaxEnt is one of the most widely used tools in ecology, biogeography, and evolution for modeling and mapping species distributions using presence-only occurrence records and associated environmental covariates. Despite its popularity, the exponential model implemented by MaxEnt does not directly estimate occurrence probability, the natural quantity of interest when modeling species distributions. Instead, MaxEnt generates an index of relative habitat suitability. MaxLike, a newly introduced maximum-likelihood technique, has been shown to overcome the problem of directly estimating the probability of occurrence using presence-only data. However, the performance and relative merits of MaxEnt and MaxLike remain largely untested, especially when modeling …


A New Method To Infer Vegetation Boundary Movement From 'Snapshot' Data, Maarten B. Eppinga, Carolyn A. Pucko, Mara Baudena, Brian Beckage, Jane Molofsky May 2013

A New Method To Infer Vegetation Boundary Movement From 'Snapshot' Data, Maarten B. Eppinga, Carolyn A. Pucko, Mara Baudena, Brian Beckage, Jane Molofsky

College of Agriculture and Life Sciences Faculty Publications

Global change may induce shifts in plant community distributions at multiple spatial scales. At the ecosystem scale, such shifts may result in movement of ecotones or vegetation boundaries. Most indicators for ecosystem change require timeseries data, but here a new method is proposed enabling inference of vegetation boundary movement from one 'snapshot' (e.g. an aerial photograph or satellite image) in time. The method compares the average spatial position of frontrunners of both communities along the vegetation boundary. Mathematical analyses and simulation modeling show that the average frontrunner position of retreating communities is always farther away from a so-called optimal vegetation …


Predicting Food-Web Structure With Metacommunity Models, Benjamin Baiser, Hannah L. Buckley, Nicholas J. Gotelli, Aaron M. Ellison Apr 2013

Predicting Food-Web Structure With Metacommunity Models, Benjamin Baiser, Hannah L. Buckley, Nicholas J. Gotelli, Aaron M. Ellison

College of Arts and Sciences Faculty Publications

Synthesis Metacommunity theory aims to elucidate the relative influence of local and regional-scale processes in generating diversity patterns across the landscape. Metacommunity research has focused largely on assemblages of competing organisms within a single trophic level. Here, we test the ability of metacommunity models to predict the network structure of the aquatic food web found in the leaves of the northern pitcher plant Sarracenia purpurea. The species-sorting and patch-dynamics models most accurately reproduced nine food web properties, suggesting that local-scale interactions play an important role in structuring Sarracenia food webs. Our approach can be applied to any well-resolved food web …


Forest Restoration And Parasitoid Wasp Communities In Montane Hawai'i, Rachelle K. Gould, Liba Pejchar, Sara G. Bothwell, Berry Brosi, Stacie Wolny, Chase D. Mendenhall, Gretchen Daily Mar 2013

Forest Restoration And Parasitoid Wasp Communities In Montane Hawai'i, Rachelle K. Gould, Liba Pejchar, Sara G. Bothwell, Berry Brosi, Stacie Wolny, Chase D. Mendenhall, Gretchen Daily

Rubenstein School of Environment and Natural Resources Faculty Publications

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 …


Multifaceted Value Profiles Of Forest Owner Categories In South Sweden: The River Helge Å Catchment As A Case Study, Gustav Richnau, Per Angelstam, Sviataslau Valasiuk, Lyudmyla Zahvoyska, Robert Axelsson, Marine Elbakidze, Joshua Farley, Ingemar Jönsson, Ihor Soloviy Mar 2013

Multifaceted Value Profiles Of Forest Owner Categories In South Sweden: The River Helge Å Catchment As A Case Study, Gustav Richnau, Per Angelstam, Sviataslau Valasiuk, Lyudmyla Zahvoyska, Robert Axelsson, Marine Elbakidze, Joshua Farley, Ingemar Jönsson, Ihor Soloviy

College of Agriculture and Life Sciences Faculty Publications

Forest landscapes provide benefits from a wide range of goods, function and intangible values. But what are different forest owner categories' profiles of economic use and non-use values? This study focuses on the complex forest ownership pattern of the River Helge å catchment including the Kristianstad Vattenrike Biosphere Reserve in southern Sweden. We made 89 telephone interviews with informants representing the four main forest owner categories. Our mapping included consumptive and non-consumptive direct use values, indirect use values, and non-use values such as natural and cultural heritage. While the value profiles of non-industrial forest land owners and municipalities included all …


New England's Community Forests: Comparing A Regional Model To Iccas, Martha West Lyman, Cecilia Danks, Maureen Mcdonough Jan 2013

New England's Community Forests: Comparing A Regional Model To Iccas, Martha West Lyman, Cecilia Danks, Maureen Mcdonough

Rubenstein School of Environment and Natural Resources Faculty Publications

This paper examines the ways in which some forms of community forests in the northeastern United States could be considered Indigenous Peoples' and Community Conserved Territories and Areas (ICCAs), based on the work conducted by the Community Forest Collaborative, a partnership of four non-governmental organisations (NGOs) in the US. The Collaborative defined a Community Forest Model for northern New England, conducted research on the economic, social, community, and conservation values of the Community Forest Model and developed case studies on five community forest projects. Five key attributes of ICCAs were selected and used to compare with characteristics of the Collaborative's …


Pattern Detection In Null Model Analysis, Werner Ulrich, Nicholas J. Gotelli Jan 2013

Pattern Detection In Null Model Analysis, Werner Ulrich, Nicholas J. Gotelli

College of Arts and Sciences Faculty Publications

Synthesis The identification of distinctive patterns in species x site presence-absence matrices is important for understanding meta-community organisation. We compared the performance of a suite of null models and metrics that have been proposed to measure patterns of segregation, aggregation, nestedness, coherence, and species turnover. We found that any matrix with segregated species pairs can be re-ordered to highlight aggregated pairs, indicating that these seemingly opposite patterns are closely related. Recently proposed classification schemes failed to correctly classify realistic matrices that included multiple co-occurrence structures. We propose using a combination of metrics and decomposing matrix-wide patterns into those of individual …


Quantifying Temporal Change In Biodiversity: Challenges And Opportunities, Maria Dornelas, Anne E. Magurran, Stephen T. Buckland, Anne Chao, Robin L. Chazdon, Robert K. Colwell, Tom Curtis, Kevin J. Gaston, Nicholas J. Gotelli, Matthew A. Kosnik, Brian Mcgill, Jenny L. Mccune, Hélène Morlon, Peter J. Mumby, Lise Øvreås, Angelika Studeny, Mark Vellend Jan 2013

Quantifying Temporal Change In Biodiversity: Challenges And Opportunities, Maria Dornelas, Anne E. Magurran, Stephen T. Buckland, Anne Chao, Robin L. Chazdon, Robert K. Colwell, Tom Curtis, Kevin J. Gaston, Nicholas J. Gotelli, Matthew A. Kosnik, Brian Mcgill, Jenny L. Mccune, Hélène Morlon, Peter J. Mumby, Lise Øvreås, Angelika Studeny, Mark Vellend

College of Arts and Sciences Faculty Publications

Growing concern about biodiversity loss underscores the need to quantify and understand temporal change. Here, we review the opportunities presented by biodiversity time series, and address three related issues: (i) recognizing the characteristics of temporal data; (ii) selecting appropriate statistical procedures for analysing temporal data; and (iii) inferring and forecasting biodiversity change. With regard to the first issue, we draw attention to defining characteristics of biodiversity time series-lack of physical boundaries, unidimensionality, autocorrelation and directionality-that inform the choice of analytic methods. Second, we explore methods of quantifying change in biodiversity at different timescales, noting that autocorrelation can be viewed as …


Advancing Agricultural Greenhouse Gas Quantification*, Lydia Olander, Eva Wollenberg, Francesco Tubiello, Martin Herold Jan 2013

Advancing Agricultural Greenhouse Gas Quantification*, Lydia Olander, Eva Wollenberg, Francesco Tubiello, Martin Herold

Rubenstein School of Environment and Natural Resources Faculty Publications

No abstract provided.


Toward A Protocol For Quantifying The Greenhouse Gas Balance And Identifying Mitigation Options In Smallholder Farming Systems, T. S. Rosenstock, M. C. Rufino, K. Butterbach-Bahl, E. Wollenberg Jan 2013

Toward A Protocol For Quantifying The Greenhouse Gas Balance And Identifying Mitigation Options In Smallholder Farming Systems, T. S. Rosenstock, M. C. Rufino, K. Butterbach-Bahl, E. Wollenberg

Rubenstein School of Environment and Natural Resources Faculty Publications

No abstract provided.


Factors Contributing To Carbon Fluxes From Bioenergy Harvests In The U.S. Northeast: An Analysis Using Field Data, Anna M. Mika, William S. Keeton Jan 2013

Factors Contributing To Carbon Fluxes From Bioenergy Harvests In The U.S. Northeast: An Analysis Using Field Data, Anna M. Mika, William S. Keeton

Rubenstein School of Environment and Natural Resources Faculty Publications

With growing interest in wood bioenergy there is uncertainty over greenhouse gas emissions associated with offsetting fossil fuels. Although quantifying postharvest carbon (C) fluxes will require accurate data, relatively few studies have evaluated these using field data from actual bioenergy harvests. We assessed C reductions and net fluxes immediately postharvest from whole-tree harvests (WTH), bioenergy harvests without WTH, and nonbioenergy harvests at 35 sites across the northeastern United States. We compared the aboveground forest C in harvested with paired unharvested sites, and analyzed the C transferred to wood products and C emissions from energy generation from harvested sites, including indirect …


Monetary And Fiscal Policies For A Finite Planet, Joshua Farley, Matthew Burke, Gary Flomenhoft, Brian Kelly, D. Forrest Murray, Stephen Posner, Matthew Putnam, Adam Scanlan, Aaron Witham Jan 2013

Monetary And Fiscal Policies For A Finite Planet, Joshua Farley, Matthew Burke, Gary Flomenhoft, Brian Kelly, D. Forrest Murray, Stephen Posner, Matthew Putnam, Adam Scanlan, Aaron Witham

Peer-Reviewed Studies

Current macroeconomic policy promotes continuous economic growth. Unemployment, poverty and debt are associated with insufficient growth. Economic activity depends upon the transformation of natural materials, ultimately returning to the environment as waste. Current levels of economic throughput exceed the planet's carrying capacity. As a result of poorly constructed economic institutions, society faces the unacceptable choice between ecological catastrophe and human misery. A transition to a steady-state economy is required, characterized by a rate of throughput compatible with planetary boundaries. This paper contributes to the development of a steady-state economy by addressing US monetary and fiscal policies. A steady-state monetary policy …