A5006403203- Ecology and Vegetation Dynamics Studies
- Bioenergy crop production and management
- Plant and animal studies
- Evolutionary Game Theory and Cooperation
- Evolution and Genetic Dynamics
- Rangeland and Wildlife Management
- Hydrology and Watershed Management Studies
- Biofuel production and bioconversion
- Botany and Plant Ecology Studies
- Forest Biomass Utilization and Management
- Economic and Environmental Valuation
- Cryospheric studies and observations
- Forest Management and Policy
- Wildlife Ecology and Conservation
- Atmospheric and Environmental Gas Dynamics
- Sustainability and Ecological Systems Analysis
- Environmental Conservation and Management
- Primate Behavior and Ecology
- Ecosystem dynamics and resilience
- Zoonotic diseases and public health
- Peatlands and Wetlands Ecology
- Species Distribution and Climate Change
- Geology and Paleoclimatology Research
- Soil Carbon and Nitrogen Dynamics
- Prion Diseases and Protein Misfolding
University of Minnesota
2011-2022
Twin Cities Orthopedics
2020
Associated Colleges of the Twin Cities
2020
Ecologie & Evolution
1996-2019
General Services Administration
2009-2015
Plant diversity and niche complementarity had progressively stronger effects on ecosystem functioning during a 7-year experiment, with 16-species plots attaining 2.7 times greater biomass than monocultures. Diversity were neither transients nor explained solely by few productive or unviable species. Rather, many higher-diversity outperformed the best monoculture. These results help resolve debate over biodiversity functioning, show at higher expected levels, demonstrate, for these...
Biofuels derived from low-input high-diversity (LIHD) mixtures of native grassland perennials can provide more usable energy, greater greenhouse gas reductions, and less agrichemical pollution per hectare than corn grain ethanol or soybean biodiesel. High-diversity grasslands had increasingly higher bioenergy yields that were 238% monoculture after a decade. LIHD biofuels are carbon negative because net ecosystem dioxide sequestration (4.4 megagram –1 year in soil roots) exceeds fossil...
Ecosystem processes are thought to depend on both the number and identity of species present in an ecosystem, but mathematical theory predicting this has been lacking. Here we three simple models interspecific competitive interactions communities containing various numbers randomly chosen species. All predict that, average, productivity increases asymptotically with original biodiversity a community. The two that address plant nutrient competition also ecosystem retention effects increase...
Three markedly different models of multispecies competition—one mechanistic, one phenomenological, and statistical—all predict that greater diversity increases the temporal stability entire community, decreases individual populations, community productivity. We define as ratio mean abundance to its standard deviation. Interestingly, communities is predicted increase fairly linearly, without clear saturation, increases. Species composition be important in affecting The more diverse caused by...
Human-caused environmental changes are creating regional combinations of conditions that, within the next 50 to 100 years, may fall outside envelope which many terrestrial plants a region evolved. These modifications might become greater cause global species extinction than direct habitat destruction. The constraints undergoing human modification include levels soil nitrogen, phosphorus, calcium and pH, atmospheric CO 2 , herbivore, pathogen, predator densities, disturbance regimes, climate....
Abstract Agriculturally degraded and abandoned lands can remove atmospheric CO 2 sequester it as soil organic matter during natural succession. However, this process may be slow, requiring a century or longer to re-attain pre-agricultural carbon levels. Here, we find that restoration of late-successional grassland plant diversity leads accelerating annual storage rates that, by the second period (years 13–22), are 200% greater in our highest treatment than succession at site, 70%...
Demand for land to grow corn ethanol increased in the United States by 4.9 million hectares between 2005 and 2008, with wide-ranging effects on wildlife, including habitat loss. Depending how biofuels are made, additional production could have similar impacts. We present a framework assessing impacts of we use this evaluate existing emerging feedstocks grassland wildlife. Meeting growing demand while avoiding negative wildlife will require either biomass sources that do not (e.g., wastes,...
An analytical model of competitive coexistence in spatial habitats, modified to address habitat destruction, predicts that the most abundant species can be among first driven extinct by given are poorest dispersers and best competitors. This contrasts with classical view biased extinction rare species. Here we explore robustness this prediction both analytically spatially explicit simulations more realistic cases. The proved surprisingly robust. dispersers, which generally competitors may...
The relative importance of environmental filtering, biotic interactions and neutral processes in community assembly remains an openly debated question one that is increasingly addressed using phylogenetic approaches. Closely related species may occur together more frequently than expected (phylogenetic clustering) if filtering operates on traits with significant signal. Recent studies show clustering tends to increase spatial scale, presumably because greater variation encompassed at larger...
Like human immunodeficiency virus type 1 (HIV-1), simian of chimpanzees (SIVcpz) can cause CD4+ T cell loss and premature death. Here, we used molecular surveillance tools mathematical modeling to estimate the impact SIVcpz infection on chimpanzee population dynamics. Habituated (Mitumba Kasekela) non-habituated (Kalande) were studied in Gombe National Park, Tanzania. Ape sizes determined from demographic records or individual sightings genotyping (Kalande), while prevalence rates monitored...
Earth undergoes long-term temperature cycles alternating between glacial and interglacial episodes. It is widely accepted that changes in Earth's orbit rotation axis cause variations solar input which drive the cycles. However, classic papers have clearly established response of climate system to orbital forcing not a simple linear phenomenon must include nonlinear feedback mechanisms. One these mechanisms ice-albedo feedback, can be modeled as dynamical system. When combined with elements...
Aggression is ubiquitous, influencing reproduction through inter- and intraspecific effects in ways that reflect life-history strategies of species. In many social mammals, females remain their natal group for life, whereas males emigrate compete rank other groups. Competition inherently risky. Therefore, it has long been hypothesized risks injury depend on an individual's sex, rank, age maximize reproductive output. However, studies quantifying such have lacking. We analyzed 20 years...
ABSTRACT Over the last half‐century, crop breeding and agronomic advances have dramatically enhanced yields in temperate summer‐annual cropping systems. Now, diversification of these systems is emerging as a strategy for sustainable intensification, potentially increasing both production resource conservation. In zones, largely based on introduction winter‐annual perennial crops at spatial temporal locations annual‐crop that efficiently increase Germplasm development will be critical to this...
Perennial biomass from grasslands managed for conservation of soil and biodiversity can be harvested bioenergy. Until now, the quantity quality harvestable in Minnesota, USA, was not known, factors that affect bioenergy potential these systems have been identified. We measured yield, theoretical ethanol conversion efficiency, plant tissue nitrogen (N) as metrics mixed-species with commercial-scale equipment. With three years data, we used mixed-effects models to determine influence...
Contrary to classical population genetics theory, experiments demonstrate that fluctuating selection can protect a haploid polymorphism in the absence of frequency dependent effects on fitness. Using forward simulations with Moran model, we confirm our analytical results showing regime, mean coefficient zero, promotes polymorphism. We find increases heterozygosity over neutral expectations are especially pronounced when fluctuations rapid, mutation is weak, size large, and variance big....