The southern California Current System (CCS) is a moderate upwelling system comprised of water masses with differing nutrient loadings and consequently community structure. The mesozooplankton community of the CCS is dominated by copepods and euphausiids; the copepod species Calanus pacificus is one of the two dominant copepod species in this region, and the dominant euphausiid species is Euphausia pacifica. The abundances of both of these species vary significantly with El Niño Southern Oscillation conditions.

Lakeshore residential development is associated with decreases in riparian zone vegetation and littoral zone structure, and increased angling effort. Depending upon the species and their associated body size, fishes may respond differently to these changes. Responses may be particularly difficult to predict for species that undergo marked changes in habitat use and diet over ontogeny, such as the popular sportfish largemouth bass (Micropterus salmoides).

Two major foundations of ecosystem science are comparative analyses and long-term studies. Here, we explore the capacity of long-term and comparative data to predict lake characteristics (LCs). We ask if a variable is best explained by neighboring lakes (NL; comparative data), lake history (LH; temporal data), or by some combination of the two.

The PAL study area encompasses a 200 x 500 km region extending from the nearshore coastal zone heavily influenced by seasonal sea ice cover to the open Southern Ocean, and from a northern area where sea ice cover is now limited to only the colder winters, to the south where perennial sea ice cover persists into summer months. In this region, primary production is dominated by unicellular phytoplankton and limited by light availability to the October-April period. The region is characterized by spring phytoplankton blooms that have declined by up to 90% in the northern region since 1978.

Although temperate forests have long been thought to be primarily nitrogen limited, resource optimization theory suggests that ecosystem productivity should be co-limited by multiple nutrients. In northeastern North America, air pollution and forest harvesting disturbance elevate N availability and contribute to the likelihood of P limitation.

 The Luquillo Schoolyard LTER program has adopted a pipeline model to guide the development and implementation of outreach activities from K12 to graduate education. At each level students are provided with authentic LTER experiences and encouraged to continue in the field of ecology research. At the middle school level, LUQ provides the Journey to El Yunque program as a free, bilingual, web-based curriculum in ecology. It uses the context of the LUQ research on hurricane disturbance to teach students about basic concepts in ecology.

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.

In arid ecosystems, current year precipitation explains a low proportion of the annual aboveground net primary production (ANPP). There is evidence that precipitation that occurred in previous years is responsible for the observed difference between actual and expected ANPP, a concept called legacy. Here, we study the mechanisms that generate these legacies, thus we will able to better understand the controls of the global carbon cycle, and to forecast changes in ANPP with a changing climate.

Biologically-mediated carbon export transports carbon from the sunlit surface layers into the ocean's interior where it can be sequestered for centuries.  It is a process mediated primarily by plankton ecology, particularly the phytoplankton that fix inorganic carbon and zooplankton that either rerespire it or repackage it into larger particles.  On a cruise in the CCE, we tracked parcels of water for four-day "cycles" during which we measured carbon flux and biological rates while measuring net changes to the plankton community.  These experimental cycles provided