Patterns of biodiversity at large spatial scales (i.e., γ diversity) can be driven by either within-community (α) or among-community (β) components. The degree to which α or β components contribute to γ diversity may depend on the amount of environmental variation that exists in the spatial extents studied. However, few studies have assessed both spatial configuration and temporal changes in biodiversity, especially in systems that frequently experience large-scale disturbance.

The dominant theme of socio-ecological research in the Luquillo LTER Research Program is the influence of land use change on local climate change, secondary forest dynamics, watershed and stream processes, and ecosystem services. Much of our research is being developed in the context of the steep urban to wildlands gradient from the Rio Piedras watershed (RPW) in the center of San Juan metropolitan area(SJMA) to the Luquillo Experimental Forest (LEF) some 25 km away.

Urbanization is one of the major threats to stream ecosystems worldwide. The phrase “urban stream syndrome” has been coined to describe patterns in degraded streams draining urban land. In Puerto Rico, urbanization now covers 16% of the island. The fully protected Luquillo Experimental Forest (focus of the LUQ-LTER) is only 23 km from the center of San Juan, a city of 1.3 million. Therefore, LUQ is assessing the impacts of urbanization on tropical stream ecosystem structure and function.

The Luquillo LTER program (LUQ) provides research experiences to undergraduate students by immersing them in its active research environment. LUQ offers a variety of programs and opportunities to undergraduate students that allow them to gain research experience and technical skills in tropical ecology. Our goals are to (1) provide students with research experiences under the advice of established scientists and (2) supplement experiences with educational activities designed to equip students with the necessary tools to conduct scientific research.

The Luquillo Forest Dynamics Plot (LFDP) is a 16-ha long-term study plot in subtropical wet forest in the Luquillo Mountains of Puerto Rico. It is part of the Luquillo LTER and the Center for Tropical Science (CTFS) network of large tropical forest plots. Forests are often subject to multiple, compounded disturbances, representing both natural and human-induced processes. Our goal is to understand forest structure, diversity and dynamics, and to predict long-term changes resulting from interactions of past human land use and intermittent hurricane damage.

The metacommunity framework integrates species-specific responses to environmental gradients to detect emergent patterns of species organization. More specifically, a metacommunity is a set of ecological communities that are potentially linked by dispersal, with each community being a group of species at a particular site.

The EcoTrends Project began in 2004 as a joint collaboration among the LTER Program, USDA Agricultral Research Service, and the USDA Forest Service with two goals: (1) to create a book illustrating trends in long -term data and showing the value of long-term data across a network of sites in addressing continental-scale questions, and (2) to make long-term biotic and abiotic data easily accessible through a common web interface with a focus on derived or aggregated data to allow cross-site analyses to be made.

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.

 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.

The Luquillo Long Term Ecological Research Program (LUQ) focuses on understanding factors driving long-term change in tropical forest ecosystems in the Luquillo Mountains. To increase our understanding of biotic and abiotic controls on ecosystems, we extended our work from the tabonuco forest to a range of forest types occurring along a climatic and forest gradient in the Luquillo Mountains.