The Chicago Region ULTRA-Ex will address a question fundamental to understanding the dynamic interactions between biodiversity conservation, ecosystem processes, and human well being in urban landscapes: In a complex urban/metropolitan system, what are the synergies and tradeoffs between conserving biodiversity and providing ecosystem services to people? The project focuses on the Green Infrastructure Vision of the Chicago Wilderness alliance, a conservation consortium of over 240 organizations.

Many ecosystems, including grassland, forest, alpine, and desert, have shown responses to N enrichment. These responses vary considerably but include changes in soil respiration rates, enzyme activities, and microbial community structure. Surprisingly, little work has examined the effects of N enrichment on soil communities and processes in agricultural systems despite the high rates of N applied in most crop production systems.

With recent shifts in public attitudes across the United States concerning the problem of global climate change, momentum is building for aggressive action to mitigate greenhouse gas emissions. At the same time, the ongoing economic recession presents challenges for financing an aggressive climate change abatement campaign; hence, it is imperative that cost-effective strategies for reducing greenhouse gas emissions be identified and pursued. To accomplish this, policy instruments will need to be tailored to a complex range of local and regional conditions.

Human land use has dramatically increased coastal watershed nitrogen exports contributing to eutrophication. Improved knowledge of sources and transformations of nitrogen in agricultural and urbanizing watersheds will be critical in developing effective coastal catchment restoration strategies. We investigated effects of land use, hydrologic conditions, and aging infrastructure on nitrogen sources and transformations in forest, agricultural, and urbanizing catchments at the Baltimore Ecosystem Study LTER site.

The temperate forests of eastern North America support high biodiversity and critical ecosystem functions while providing natural resources and cultural benefits to an expanding human population. The region is shaped by a legacy of landscape change: major shifts in climate, vegetation and disturbance at millennial time scales; extensive deforestation for agriculture in the 17th – 19th centuries; and abandonment of farmlands, natural reforestation and increasing urbanization through the mid-21st century.

A field experiment has been initiated in August 2008 to determine if the vegetation of a coastal marsh is in synchrony with hydrologic conditions that have developed with rising sea-level. The hypothesis being tested is that plant community structure will persist in existing zones of vegetation in the face of sea-level rise unless disturbance provides opportunities for species change under more frequent tidal inundation.

Tropical environments are changing fast due to deforestation and regrowth, urbanization, climate change, and other forces. The consequences are immense for the whole array of ecosystem services people require. The Luquillo Long-Term Ecological Research Program (LUQ) is tackling these issues in Puerto Rico. LUQ began in 1988 and focused on natural disturbances (hurricanes, landslides, droughts, floods) and ecosystem response. That work revealed patterns of resistance and resilience to cycles of natural disturbance.

Urban landscapes contain a mix of land-use types with different patterns of carbon (C) and nitrogen (N) cycling and export. These patterns affect interactions between ecosystems and the atmosphere.  We have measured soil:atmosphere fluxes of carbon dioxide (CO₂), nitrous oxide (N₂O) and methane (CH₄) in four urban grassland and eight forested long-term study plots in the Baltimore, MD USA metropolitan area monthly since 1998.

Stabilization of organic matter on mineral surfaces strongly affects rates of soil organic matter (SOM) accumulation and turnover. Controls over SOM are of particular interest in arid and semi-arid systems where the abundance of woody plants has increased globally over the past century. This proliferation of woody plants may lead to significant soil organic carbon (SOC) accumulation, although a large degree of uncertainty exists in the direction and magnitude of SOC pool responses to woody encroachment.