Berry Center 231
Program in Ecology Faculty represent many different departments and offer diverse expertise and interests, but all share a core commitment to research and graduate training in ecology. All students enrolled in PiE are advised or co-advised by a PiE Faculty member.
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My main interest is in landscape ecology, focusing on human and natural disturbances in Southern Rocky Mountain landscapes, historical changes in landscapes, and implications for natural resource management. Recent research projects have included global change effects on treeline in Rocky Mountain National Park, fire history in montane and subalpine landscapes in Rocky Mountain National Park, effects of a large natural blowdown in northern Colorado, and landscape change in the San Juan Mountains. I use GIS as a tool in many analyses, as well as spatial models, global positioning systems, and other quantitative geographical tools. I have recently coedited books on forest fragmentation in the southern Rocky Mountains (Univ. Colorado Press), spatial modeling of forest landscape change (Cambridge Univ. Press), and fire and climatic change in temperate ecosystems of the western Americas (Springer), and am coauthor of a forthcoming book on legacies of human activities in Southwestern Colorado and promising visions for restoration (Univ. of Utah Press). I am initiating work on restoration of native plants in degraded semi-arid landscapes and a book-length treatment of the natural vegetation of the Southern Rocky Mountains.
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My research interests lie in wildlife habitat ecology and restoration ecology with a focus on restoring the functionality and structure of wildlife habitats in disturbed rangeland systems, particularly sagebrush habitats. The types of research questions that my lab addresses typically are guided by ecological concepts that are used as a framework to evaluate conservation questions. We use a variety of tools to obtain data to answer our questions including estimation of demographic parameters, field experimentation, habitat modeling, nutritional analyses, population monitoring, statistical modeling, and vegetation measurements. Two general areas of emphasis that my lab is pursuing are: (1) understanding the direct and indirect impacts of anthropogenic development on vertebrate species (greater sage-grouse and ungulates as model taxa) inhabiting sagebrush habitats, and (2) evaluating the efficacy of mitigation techniques and conservation practices intended to enhance habitat conditions or mitigate effects of anthropogenic development in sagebrush habitats. In all studies we seek to understand responses of habitat restoration efforts across a range of spatial and temporal scales to better inform conservation practices.
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My main interest revolves around the interaction between animal behavioral ecology, population dynamics, and ecosystem function. I mainly study carnivores and use the transport of nutrient from sea to land as a model system. To study those interactions, I use isotopic and genetic tracers. For example, I investigate the effects of trade-off between nutritional requirements and risk of infanticide on consumption of salmon by female brown bears, and how female decisions made based on this trade-off influence the transfer of salmon-derived nutrients to terrestrial vegetation.
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My research interests lie within behavior, ecology and evolution. What unites them is my belief that many interesting and important questions can only be answered with an understanding of resource availability. Consequently, much of my research has focused on linking resource availability to various aspects of behavior, ecology and evolution. We mostly study crossbills (Loxia) because we can quantify resource availability in the wild and we can bring food resources into the laboratory where we can ask meaningful questions with captive crossbills. It also allows us to combine our interests in behavior, plant and animal ecology, and evolution. One of my current projects addresses whether and how a coevolutionary arms race between crossbills and lodgepole pine is causing crossbills to speciate and another project is determining how important coevolution has been in the adaptive radiation of crossbills.
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Research in my lab focuses on the genetics of adaptation and speciation. Both of these evolutionary processes operate within an ecological context. Thus, I am particularly interested in understanding the basis of traits that have functional and ecological importance. Similarly, I am interested in the ecological determinants of the outcomes of hybridization, including speciation. The reason for studying the genetics of these evolutionary processes is that knowledge of the underlying genetics can reveal important details of the dynamics of adaptation and speciation. Current research in the lab includes genetic analyses of hybridization and adaptive differentiation among diverse taxa (mice, fish, butterflies, cottonwoods, spruce, etc.). For many of these projects we develop novel computational analyses of genetic and phenotypic data.
Director of the Haub School of Environment and Natural Resources
Wyoming Excellence Chair, Professor of Botany and Ecosystem Science and Management
E-mail: firstname.lastname@example.org | Web Page | Recent Publications
Students: Oggie Avirmed
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Biogeochemical cycling in semiarid ecosystems, at local to regional scales; Soil carbon and nitrogen turnover; Nitrogen retention in soils; Influences of land use management on net ecosystem production and C, N, and P storage; Almost anything at all about ecosystem ecology!; Environmental literacy for college students; Pedagogical techniques.
Professor of Zoology and Physiology - no longer accepting new students
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I am no longer accepting new students. I am interested in a wide range of terrestrial ecological processes, including community structure, small population processes, landscape-level environmental change, and population genetics. The animal models that I study include various mammalian taxa, but I work mostly with small and mid-sized carnivores and their prey. The tools used by my students and me are exceedingly diverse, and chosen to fit the question, taxon, location, and circumstances of the study. They include biotelemetry, molecular markers, stable isotopes, GIS, and observing animals with our eyes. Most of the research I do is somehow related to an animal conservation issue, although in some cases indirectly.
Students: Shawn Billerman
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Research in my lab focuses on understanding the processes of speciation and adaptation in birds. While we focus primarily on these questions from a genetic perspective, we must also consider the environments inhabited by the birds we study. Current projects include: 1) a detailed dissection of gene flow and introgression across the hybrid zone between Lazuli (Passerina ameona) and Indigo (Passerina cyanea) buntings; 2) a broad comparative hybrid zone study focusing on a number of avian species pairs that hybridize in the Great Plains (e.g. Passerina buntings, Icterus orioles, and Pipilo towhees); 3) patterns of functional differentiation in Tachycineta swallows; and 4) a investigation of the impact of extreme environments (high elevation, high latitude) on the evolution of mitochondrial genes.
Students: Jason Carlisle
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I study wildlife-habitat relationships and the ecological, behavioral, and evolutionary processes underlying patterns in habitat use and quality at multiple spatial scales. My lab is currently focused on the influence of anthropogenic changes to habitats (e.g., via oil and natural gas extraction) on non-game wildlife species including songbirds, small mammals and herpetofauna, especially within sagebrush systems. My work has also focused on broad scale life history patterns and avian parental care behaviors.
Students: Morgan Churchill
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My research interests center on understanding the ecological relationships among organisms within ancient ecosystems. For the past several years, I have been particularly interested in the study of the evolutionary ecology of marine mammals including sirenians (e.g., manatees, dugongs) and cetaceans (e.g., whales, dolphins, porpoises). The primary tools I use for this research are stable isotope analyses of the inorganic and organic fraction of fossil remains, which can provide information on the diet and habitat preferences of extinct organisms that might not be interpretable from the morphology or depositional setting. Recently, an increasing component of my research has included work in modern marine and terrestrial ecosystems as a means of testing interpretations of geochemical results from fossil remains. Two examples of these projects include a long term study of the feeding habits of manatees in the Indian River Lagoon of Florida and analysis of lifetime feeding habits and nutritional ecology of desert tortoises in the Sonoran and Mojave Deserts with colleagues at the Smithsonian National Zoological Park.
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My research encompasses the theoretical and applied aspects of insect ecology and biological control, the use of living organisms to control insect pests and weeds. A current research focus is the behavioral and population ecology of host specificity in insects used as weed biological control agents. The primary question is: what behavioral and ecological factors influence host specificity and impact of biological control agents in the field? The key goal is to maximize impact on the weed and minimize impact on native, non-target species. A second area of research involves interactions among parasitoid wasps used in biological control of Hawaiian fruit fly pests. Here the key issue is coexistence of competing species, and direct and indirect interactions in parasitoid-host food webs.
Students: Susma Giri
I am interested in functional adaptations of organisms to their environment. I use a variety of techniques in both the laboratory and in the field. I focus on insects because they dominate the terrestrial biosphere (at least among metazoan taxa), where they inhabit a wide array of environments, and because they are evolutionarily, morphologically, and functionally diverse. Some current projects include: flight and thermal physiology of alpine bumblebees, physiological explanations for body size clines, climate change and plant-pollinator interactions, and physiological impacts of recent climate change.
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My research projects span population and community ecology, and also a variety of interests in both conservation biology and also basic ecology and life history biology. My students work on an even broader range of interests. Past students have worked on topics as diverse as raptor-rodent interactions, honey bee-bumble bee competition, parasitic plant ecology, exotic tree diseases, and behavior of aposematic beetles. Current lab members are similarly broad. My own current projects include the demography and control of range limits of arctic-alpine plants, the role of termites in structuring East African savannah communities, and the use of demographic models to predict extinction risk and the best management methods for numerous threatened species.
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My research in plant physiological ecology focuses on discerning the physiological controls of the fluxes of water, carbon, and nutrients through ecosystems. Several research projects are underway in my laboratory, utilizing techniques such as sap flow, porometry, centrifuge-based vulnerability to cavitation, stable isotopes of carbon, hydrogen, and oxygen, soil physical measurements, and direct measurements of biomass partitioning in plants. I am investigating the impact of time since fire, tree species composition, and soil drainage on the water budgets of boreal forests in central Manitoba, and the impact of tree species and landscape position on carbon and water cycling in forests of northern Wisconsin and the Medicine Bow Mountains of Wyoming. In collaboration with Dr. Elise Pendall, I am quantifying the effects of fire on carbon and water fluxes from sagebrush steppe at sites in Wyoming.
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My research interests lie at the nexus of conservation biology and community ecology. Currently, I am devoted to two research programs: 1) examining how the loss of megaherbivores and other wildlife affects rangeland dynamics in savanna ecosystems through the Ungulate Herbivory Under Rainfall Uncertainty (UHURU); and 2) investigating the interplay between community saturation and human disturbances across wildlife assemblages. Graduate projects in my research group span a breadth of topics, and include precipitation and herbivory as filters to plant community assembly, foraging efficiency/risk tradeoffs in herbivores, community- and ecosystem-level consequences of wildlife restoration in Mozambique, small mammal responses to ungulate extirpations, and landscape change and conservation of a globally-endangered antelope in northeastern Kenya.
Students: Erin Hotchkiss
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Research Interests: I study stream and river ecology. My work extends from population biology of invasions to biogeochemistry of nitrogen, and organisms range from microbes to fish. I am most interested in linking population ecology with ecosystem ecology and some current questions ask how animals alter nitrogen cycling in streams. I am also interested in food webs, because they provide a framework for understanding links between animal populations and ecosystem processes (such as consumption of primary production). Some current projects are:
Students: Kristen Gunther
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I am a shrubland ecologist who focuses on restoration of shrublands in the face of exotic invasive species, fire and anthropogenic uses such as grazing and mining. My research targets primary and secondary impacts of invasive species on sagebrush steppe, northern mixed prairie grasslands, salt desert shrublands, and threatened and endangered species in Wyoming, Colorado and the Intermountain West. As a result, I have worked in habitat management for Colorado butterfly plant, Greater sage grouse and with revegetation efforts on the Snake River Plain, Thunder Basin and on wildlife refuges in the Wyoming Basin and tallgrass prairies. My students have examined response of native vegetation to invasive species and management history using greenhouse, field, genetic, biocontrol and spatial database approaches. I teach graduate courses in rangeland resources, shrubland ecology, research proposal writing, and the graduate seminar in Research Across Disciplines (RAD).
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Research in my lab centers on ecological responses to environmental variation (particularly climate) at decadal to millennial timescales. I am particularly interested in linking ecological processes and climatic dynamics across timescales. We use a variety of tools to study past climatic variation and ecological changes, including pollen and plant macrofossils (from lakes, wetlands, and woodrat middens), tree-rings, stable isotopes, and testate amoebae. Ongoing projects include (1) the role of centennial to millennial climate variability in pacing late Holocene woody-plant migrations and population dynamics in the central Rocky Mountains and western Great Lakes regions, (2) the Quaternary biogeographic history of pines, spruces, and other trees in North America, and (3) the relative roles of successional processes and climate change in governing dynamics of wetlands. I am also initiating biogeographic and paleoeocological studies in the mountains of northeastern Mexico.
Students: Doug Keinath
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My research interests range from demography and population dynamics of animal species, to community-level consequences of herbivory and predation, and landscape ecology of wildlife populations. A common theme of much of my work is a desire to connect ecological research with applied conservation issues, particularly regarding animal populations. Some recent projects have evaluated the management and recovery of peregrine falcons, the effects of range management on carnivores in southern Africa, the dynamics of elk populations, and trophic interactions among wolves, elk and aspen. Much of my current work, and that of my students, is focused on the ecology and management of Rocky Mountain ungulates and their predators. Nevertheless, interesting ecological questions that have a bearing on real-world conservation will always capture my interest regardless of taxa or study system. As the Assistant Unit Leader for Wildlife at the Wyoming Cooperative Fish and Wildlife Research Unit, my research program also addresses the priority needs of state and federal wildlife managers. Consequently, students in my lab often work closely with wildlife managers outside of academia.
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In my research, I seek to develop our understanding of host-parasite relationships and the biology of invasions in an ecological and evolutionary context. For example, I study the role of ecological stoichiometry in the success of the non-native New Zealand mud snail and the ecological and evolutionary consequences of the introduction of lake trout to zooplankton in Yellowstone Lake. Using snail- trematode interactions, I also study the consequences of parasitism to the evolution of host-life histories and how varying the stoichiometry of food alters the outcome of snail-trematode interactions.
I am very broadly interested in ecosystems in dry areas. My past work has focused largely on grasslands and I expect most of my future research to shift towards questions associated with mixtures of grasses and shrubs or in ecosystems dominated by shrubs. A portion of my research has focused on plant population and community ecology. Within these general topics, my students and I have worked on demography, controls on recruitment, resource partitioning between grasses and woody plants, responses to and recovery from disturbance ranging from small to large spatial scale including grazing by domestic livestock. Another branch of the research my students and I have conducted falls within the realm of ecosystem ecology and has included above and belowground net primary production, carbon budgets, and water balance. I use simulation modeling as a key exploratory and analysis tool across all of the organizational and spatial scales of my research.
Assistant Professor of Mathematics and Zoology
College of Arts and Sciences (Philosophy & Creative Writing)
My research interests are mathematical biology, differential equations, dynamical systems, and their interface. My research projects involve formulation, analysis and applications of deterministic mathematical models for infectious diseases and ecological systems. The models are aimed to answer questions and help gain useful insights for the biological systems being investigated. Based on the theoretical analysis and numerical simulations, we describe useful quantitative behaviors of model solutions and tackle which factors are most important in determining these behaviors. Together with collaborating biologists, we provide biological interpretations of the mathematical results, as insights and predictions. From time to time, we need to develop new or improve existing mathematical theories and techniques to provide satisfactory solutions to questions posed by collaborating biologists.
Students: Christa Cooper
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I conduct research that focuses on studies, analyses, explorations, syntheses, critiques, and expressions of the interface between natural sciences and the humanities/arts. This work includes, but is not limited to, philosophy and creative writing. My studies in philosophy pertain to environmental and natural resource ethics, as well as environmental justice. My efforts in writing are primarily in the genre of creative non-fiction and nature writing, including book-length works, essays, and shorter pieces. I also pursue scholarly studies at the interface between religion and the natural sciences, with a focus on the transcendental tradition, intellectual pluralism/pragmatism, and panentheistic perspectives.
Students: Mikey Tabak
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I am a functional ecologist. My research focuses on the mechanisms that animals use to garner resources and on the evolutionary causes and ecological consequences of these mechanisms. For both scientific and esthetic reasons, I work with animal-plant mutualisms. In my laboratory we study birds and bats that pollinate flowers and that disperse seeds. We study how they assimilate food, how they use the nutrients that they assimilate to grow and reproduce, and how they detoxify the nasty substances that are often found in natural products. We use simple mathematical models to scale up the physiological processes in organs and organisms to their consequences for ecosystem processes. We have three active areas of research in the laboratory: 1) We are investigating how nectar-feeding animals cope with the astounding amounts of water that they ingest; 2) we are using the distinctive stable isotope signatures of carbon and hydrogen in succulent CAM plants to track the flux of resources from this functional group of plants into the coterie of animals that consume their nectar and fruit in subtropical desert ecosystems; and 3) we are investigating how seed-dispersing birds create pattern in the spatial distribution of the mistletoes that they feed on.
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I work at the intersection of behavioral ecology, demography and molecular ecology. I am interested in how social systems interact with genetic structure in lek-mating birds, in how landscapes have affected the geographic structure of vertebrate populations and how matrix-based demographic models illumine social behavior. Although my primary organismal interest is birds, my students have used genetic markers to explore questions in mammals and fish as well as birds. Current projects include the evolution of cooperation in lek-mating Long-tailed Manakins (Costa Rica), the genetics and mating system of high-elevation rosy-finches, and the demography of endangered black-footed ferrets.
My interests lie in how ecosystems have responded to past climate changes. I am a paleoecologist who works primarily on arid and semi-arid ecosystems (deserts to forests) in western North America and how those ecosystems respond to prolonged climate change like drought and to short-term disturbances like floods and fires. The primary tool I use for analyzing past ecosystem dynamics is pollen, macrobotanical remains and charcoal deposited on and contained within lake and wetland sediments. My lab currently has projects looking at the interactions between climate forcing and changes in stable states of desert wetland and grassland. I am investigating the resilience of western forests to prolonged drought (century to millennial scale) that may be coupled with changes in fire-regimes as possible analogs to future forest dynamics under climate change scenarios.
My research program is focused on addressing applied questions of ecological complexity at landscape scales utilizing tools from landscape ecology and population genetics. The goal of my research is to address complex ecosystem dynamics, focusing on biodiversity (distribution and abundance) and functional connectivity in areas of management and conservation concern. My objective is to incorporate ecological research and alternative management scenarios to assess sustainability. While most of my current work focuses on amphibians and related ecological systems, I have experience with a broad range of taxonomic groups and their related ecological systems: carnivores, ungulates, small mammals, birds, and a coniferous plant. I expect build a research program addressing a broad range of taxonomic groups with a focus on rangeland systems. I have three major interrelated areas of research: 1) Ecosystem Biodiversity - ecological and anthropogenic processes and how they constrain species distributions, 2) Functional Connectivity - system connectivity and how it limits population persistence, and 3) Landscape Change - impact of alternative future landscape conditions on ecosystem sustainability.
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My research lies within the areas of both basic and applied science, concentrating on questions formed to evaluate the impact of anthropogenic or chronic disturbances on ecological underpinnings of ecosystem resiliency and sustainability. As a biogeochemist I am drawn toward understanding the linkages between belowground N and C cycling and ecosystem functions. I am interested in agroecological principles governing sustainable food production in time of diminishing natural resources and environmental change and the short and long-term consequences of climate variability on ecosystems services. In my research approach I investigate a variety of soil, air and plant indices that are most sensitive to environmental change such as greenhouse gas (GHG) emissions (carbon dioxide, methane and nitrous oxide) and labile and stable organic matter pools. Methodologies I often employ include GHG measurements, assays for determining potentially mineralizable C and N, and gross rates of mineralization using 15N enrichment techniques. I am currently involved in the following projects: (1) Quantifying the impact of a massive bark beetle outbreak on carbon, water and nutrient cycling and regeneration of southern Wyoming lodgepole pine forests; (2) Development and transfer of conservation agriculture production systems for small-holder farms in eastern Uganda and western Kenya; (3) Effects of cropping-system, irrigation method, and soil properties on soil nitrogen and organic matter dynamics in the Big Horn Basin; and, (4) Economic and environmental sustainability of conventional, reduced-input, and organic approaches on western crop-range-livestock farms.
I conduct research on carbon and water fluxes between terrestrial ecosystems and the atmosphere, and on the effects of global changes such as increasing carbon dioxide concentrations and land-use change on these fluxes. An important component of my work involves the use of stable isotopes as tracers to better quantify small changes in these fluxes that might not otherwise be detected. I also use stable isotopes in terrestrial proxies (tree rings, packrat middens, pedogenic carbonates) to reconstruct past changes in climate and hydrology.Current research projects evaluate ecosystem-scale consequences of climate change in semi-arid grassland, and of bark beetle induced mortality in lodgepole and spruce-fir forests. We are investigating mechanisms that explain how altered biogeochemical cycles can feed back to climate change and disturbance.
Students: Dan Gibson-Reinemer
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My research involves fish ecology with a particular focus on streams, habitat relationships, and landscape ecology. My graduate students and I are addressing issues of fish habitat use and movement patterns in regards to both large spatial scales and patchiness. We are interested in what constitutes a habitat patch, how patches are rearranged by disturbances such as floods, and what factors influence fish movement among patches. Another area of interest is the homogenization of aquatic biota across the world through habitat alteration and species introductions. Much of our research involves species of conservation concern including native trout and nongame fishes such as native minnows in prairie streams. One of our current projects in this area involves the role of irrigation canals as a population sink for cutthroat trout.
Students: Jason Edwards
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Research in my lab is primarily at the ecosystem level--particularly biogeochemical processes with a strong temporal-spatial orientation. My long-term goal is to better understand the controls of ecological processes across a wide range of scales, from meters to kilometers to 1000s of kilometers. Typically, my colleagues and I examine these processes in the context of temporal variation as resulting from disturbance events followed by succession, and in terms of spatial variation occurring across landscapes or regions. GIS and remote sensing tools are involved in virtually all projects in his lab. While ecosystem questions are foremost in our laboratory, many activities could also be described as "landscape ecology." We are involved in producing ecologically meaningful maps of local landscapes and the state as a whole, and in modeling processes such as alien plant invasions, pollen transport and redistribution of snow by wind using GIS and statistical tools. A primary focal area is on the propagation of cause and effect across landscapes through transport mechanisms.
Students: John Calder
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My research focuses on long-term changes in the availability of water, and how these changes shape ecosystem composition, pattern, and process. In particular, I have been using geologic evidence to study how the water levels of lakes in North America have changed over centuries to millennia during the past 15,000 years, and am comparing these records of past moisture levels with fossil and geochemical evidence of past vegetation, disturbances, and other ecosystem phenomena. In doing so, I seek to understand how ecosystems from the landscape- to continental-scale respond to climate change. By comparing lake-level data from across the continent, I am also examining the climatic processes that cause moisture fluctuations through time. Students working with me have worked on 1) paleoclimate reconstruction and diagnosing the causes of past climate changes, 2) vegetation and fire history reconstruction and examining the role of disturbance (fire) for mediating vegetation responses to climate change, 3) spatially-explicit landscape modeling of past ecosystem changes, and 4) improving our understanding of the sedimentary and geochemical record of past environmental change.
My research focuses on mapping vegetation types and monitoring vegetation condition and land cover change using remotely sensed data. Most of my work uses multispectral data collected from satellite and airborne platforms. Study areas range from small agricultural fields to large river deltas. Working with remotely sensed data acquired at different spatial and spectral resolutions enables me to assess the effect of scale or grain size on mapping vegetation and other earth surface features. My research sites are located in US (Wyoming and Texas), India, Uzbekistan, Kazakhstan, Russia, Mexico, Honduras and Nicaragua.
Students: Caley Gasch
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The foci of my research program are soil microbial ecology and restoration ecology and the interface of these two disciplines. I employ an integrated approach in my work combining analyses of community structure and function as well as environmental influences. Topics we are currently investigating include: 1) spatial and temporal variability of soil microbial communities; 2) response and recovery of soil microbial communities and their ecosystem functions to various forms of disturbance; 3) influence of land management practices on soil microbial community structure and function.
Students: Kellen Nelson
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Much of my research is conducted in the Greater Yellowstone-Teton Ecosystem in northwestern Wyoming, and involves ecosystem responses to large, natural disturbances such as fire. In addition, I use GIS and remote sensing to investigate the consequences of landscape-scale spatial heterogeneity in ecological systems. My current work is focused on understanding how the observed variation in post-fire plant communities in the Greater Yellowstone-Teton Ecosystem affects important ecosystem processes such as decomposition and nitrogen mineralization, how these processes vary at the landscape scale, and how the effects of post-fire community structure change over time in young, developing forests.
I am interested in the resistance and resilience of aquatic communities to disturbance. My research addresses disturbances (flow alteration, climate change, nutrient loading, and energy development) that are relevant to the conservation and management of aquatic ecosystems through a combination of field observation, experimentation, and modeling. Recent projects have explored low flow disturbance in stream communities, nutrient loading by anadromous alewife, phytoplankton phenology, and the impacts of water diversion and climate change for juvenile Chinook salmon. Much of my current research involves fish that are of conservation concern and is set in a management context. My goal is to conduct research that has relevance to both basic ecological theory and fisheries management.
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Our research focuses on microbial genomics, ecology, and systematics, and interactions between these research areas. Specifically, we study the biology of the planctomycetes, acidobacteria, and verrucomicrobia, using genomic and post-genomic approaches. These three groups, while phylogenetically unrelated, are united in having a cosmopolitan distribution in aquatic and terrestrial environments, and being relatively understudied and poorly characterized. We are starting to gain an understanding of their ecological importance - e.g. some planctomycetes have been recently demonstrated to carry out the anaerobic oxidation of ammonium (³anammox²), and it appears that anammox planctomycetes play a significant role in the global nitrogen cycle - but much work remains to be done. A secondary focus is the structure and function of microbial communities, both free-living East African savanna soils, deep-sea coral habitats, and Galapagos Rift hydrothermal vents), and associated with the human host (gastrointestinal and reproductive tracts).
Associate Professor of Evolutionary Genetics
Departments of Botany and Molecular Biology
The majority of variation segregating in natural populations is quantitative, and its expression depends on genetic background, environment, and interactions with these two factors. Traditionally, the evolution of quantitative traits has been described using statistical genetic techniques. However, one of the greatest advantages of these approaches is also one of their primary limitations: it is possible to estimate genetic variation and covariation in traits without any direct knowledge of the underlying loci or molecular genetic details. In like fashion, it is possible to estimate the pattern of natural selection on quantitative traits in the absence of knowledge of loci that determine fitness. Advances in collecting and analyzing molecular data promise to reveal the molecular genetic basis of quantitative trait variation. In our lab, we focus on understanding genetic mechanisms of adaptation to competition, the role of the circadian clock in competitive responses and in adaptation to seasonal settings, and the genetic basis of quantitative variation in floral morphology. In sum, our work spans the fields of ecology, evolution, and genetics.
Students: Janet Chen
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I am a plant physiological ecologist who uses stable isotopes to investigate plant responses to environmental changes in space and time, and the expression of plant metabolic functions at the ecosystem level.
My current projects focus on (1) the role of precipitation variability in grassland and savanna ecosystem dynamics, (2) integration of carbon and water cycles in environments characterized by pulsed resource renewal, (3) spatial and temporal patterns of resource capture by woody plant root systems, (4) plant controls on ecosystem water balance, and (5) isotopic records of plant responses to climate change in deserts.