You are here

Projects

Linking remotely sensed optical diversity to genetic, phylogenetic and functional diversity to predict ecosystem processes

Our goal is to apply novel methods to test hypotheses linking dimensions of diversity in ecosystems examining plants aboveground and soil organisms belowground.

Monitoring biodiversity and understanding its consequences for ecosystem and global processes are critical challenges in the face of rapid global change. However, there are constraints on measuring biodiversity imposed by limited research funding. Developing less expensive methods that can be used comprehensively in space and time will significantly advance biodiversity research. Remote sensing offers promise in this regard. Plants display themselves towards the sky in contrasting ways based on their evolutionary history, their genetic make-up, their form, phenology and the nature of their interactions with the environment. Differences among plants in these aspects can be detected by optical sampling, allowing remote sensing to assess diversity.

We will use three biodiversity manipulations at the Cedar Creek Ecosystem Science Reserve that vary genotypes within species, species with different functions and responses to resources, and species from different evolutionary lineages to test whether these kinds of diversity can be detected remotely at multiple spatial scales.  Project scientists from four institutions, including the University of Minnesota, the University of Wisconsin, the University of Nebraska-Lincoln and Appalachian State University will investigate the nature of linkages between plant biodiversity, soil microbe diversity and ecosystem function. These efforts will serve in the development of airborne and satellite platforms that can routinely monitor biodiversity. In doing so, the study will examine the evidence for the concept of surrogacy, such that one metric of biodiversity can be used to provide information about others. We predict that many aspects of diversity can be detected remotely at multiple scales of spatial resolution.

Ultimately, the project seeks to transform methods for detecting changes in biodiversity worldwide and will provide numerous training opportunities in science, technology and math (STEM) for young scientists. Results will be integrated into the Cedar Creek Schoolyard Ecology program and a NASA-funded STEM Education Center to train Native American reservation teachers. Citizen scientists will be engaged through the MN Phenology Network. Data and research outcomes will be archived in publicly accessible data repositories. NSF-NASA DEB-1342872

Adaptive differentiation, selection and water use of a seasonally dry tropical oak: implications for global change

We are merging genetic and physiological approaches to characterize patterns of natural selection and adaptive differentiation among populations from contrasting climatic regimes under natural and experimentally imposed water limitation.

Climate change will alter key aspects of the environment for plants, such as temperature and water availability. Very little is known about how plants will contend with these changes, particularly species that are difficult to study, such as long-lived tropical trees. This project examines short-term physiological responses and the potential for long-term evolutionary changes in response to experimental manipulations of precipitation in populations of a tropical oak species that occur in different climates in Central America. We are investigating the extent to which these populations are adapted to the climate they currently experience and their potential response to climates that are similar to those predicted for the future. A critical component of this work is to investigate whether impacts of climate change at the seedling stage enhance or constrain adaptation at later life stages of the tree. We also aim to identify the physiological and genetic mechanisms that enhance or limit adaptation to altered climates in this tropical tree. My lab is leading this 5-year, NSF funded project that brings together researchers from the University of Minnesota, Cornell University, the University of Zamorano in Honduras, the Area Conservacion Guanacaste in Costa Rica, and CIEco-UNAM in Morelia, Mexico. NSF IOS-0843665


Phylogeny of the New World oaks: Diversification of an ecologically important clade across the tropical-temperate divide

A collaborative US-Mexican effort to gain insights into the origins, maintenance and consequence of diversity in the New World oaks

Oaks (the flowering plant genus Quercus) include some of America’s most ecologically and economically important trees. The approximately 255 oaks of the New World oak lineage dominate North American and Mexican woody plant biomass, biodiversity, ecology, and nutrient cycling. Despite the significant ecosystem services provided by oaks, the biodiversity of this genus is poorly understood. We are working with a collaborative team of US and Mexican scientists to undertake a comprehensive systematic study of the oaks of the New World. The project will integrate next-generation genomic (DNA) sequencing, plant physiology, and direct study of plants in the field and museum collections to gain insights into the oak tree of life and the basic question of how oak traits, distributions, and diversity evolve in response to changes in habitat and climate.

Understanding of how oaks respond to shifts in climate and habitat is essential to conserving forest biodiversity and healthy forest ecosystems for future generations. The project will broadly disseminate findings and increase biodiversity awareness and understanding across diverse audiences in several ways: strengthening of an international oak collaboration among U.S., Mexican, and European researchers; training of undergraduate through postdoctoral biodiversity researchers; training K-12 teachers and their students in biodiversity science; and public outreach through museums, botanical gardens, and online venues. NSF-DEB-(March 2012-2015)


Long-term Ecological Research: Linking phylogenetic history, plant traits and ecological processes at multiple scales

The overarching goal of this effort is increase understanding of the extent to which phylogenetic history influences ecological processes. We are particularly interested in understanding how adaptations that evolved in other contexts drive modern-day community dynamics.

 

 

In the face of rapid changes in the Earth’s biota, understanding the evolutionary processes that drive patterns of species diversity, differentiation, and coexistence in ecosystems globally is pressing. Advances in this knowledge base through computational methods, analytical approaches, long-term observations and well-designed experiments are essential to sustaining the complex interactions and ecosystem functions of the living world. We are conducting ongoing work at Cedar Creek Ecosystem Science Reserve and in collaborative studies in North America and abroad linking phylogenetic history, plant traits and ecological processes at multiple scales. NSF DEB-0620652


Ecological Homogenization of Urban America

We are testing the hypothesis that human impacts in and around cities causes homogenization of the biota, altering functional and phylogenetic diversity patterns, ecological structure, and ecosystem functions relevant to carbon and nitrogen dynamics, with continental scale implications.

Urban, suburban and exurban environments are important ecosystems and their extent is increasing in the U.S. The conversion of wild or managed ecosystems to urban ecosystems is resulting in phylogenetic, functional and ecosystem homogenization across cities, where neighborhoods in very different parts of the country have similar patterns of roads, residential lots, commercial areas and aquatic features. The research provides a framework for understanding the impacts of urban land use change from local to continental scales utilizing datasets ranging from household surveys to regional-scale remote sensing across six metropolitan statistical areas (MSA) that cover the major climatic regions of the US (Phoenix, AZ, Miami, FL, Baltimore, MD, Boston, MA, St. Paul, MN and Los Angeles, CA). We seek to determine how household characteristics correlate with landscaping decisions, land management practices and ecological structure and functions at local, regional and continental scales. This research will transform scientific understanding of an important and increasingly common ecosystem type ("suburbia") and the consequences to diversity, carbon storage and nitrogen pollution at multiple scales. In addition, it will advance understanding of how humans perceive, value and manage their surroundings.