Treesearch

Current LiDAR-based methods for detecting forest change use a host of statistically selected variables which typically lack a biological link with the characteristics of the ecosystem. Consensus of the literature indicates that many authors use LiDAR to derive ecosystem morphological traits (EMTs)—namely, vegetation height, vegetation cover, and vertical structural complexity—to identify small-scale changes in forest ecosystems. Here, we provide a conceptual, biological model for predicting forest aboveground biomass (AGB) change based on EMTs. We show that through use of a multitemporal...

Hurricanes can cause severe damage to tropical forests. To understand the nature of hurricane impacts, we analyze and compare immediate effects from category-4 hurricane María in 2017 and category-3 hurricane Hugo in 1989 at Bisley Experimental Watersheds (BEW) in the Luquillo Experimental Forest, Puerto Rico. We show that hurricane María caused lower mortality than hurricane Hugo, even though hurricane María was a stronger event with higher sustained wind. The lower mortality was due to the combination of lower accumulated cyclone energy at the site and more wind-resistant forest structure...

Nonnative tree species have received less scientific attention than nonnative species in general, but when a forest is colonized by a nonnative tree species, the ecological effects can be significant as a change in tree species composition can alter the structural and functional attributes of forest ecosystems. We assess the abundance, geographic distribution, contribution to forest structure (including carbon), and temporal trends of nonnative tree species between the most current inventory and the previous one, ranging from 3 to 15 years earlier, within the conterminous United States...

Catchments in the Luquillo Experimental Forest (LEF) of Puerto Rico are warm, wet and tropical with steep elevational relief creating gradients in temperature and rainfall. Long-term objectives of research at the site are to understand how changing climate and disturbance regimes alter hydrological and biogeochemical processes in the montane tropics and to provide information critical for managing and conserving tropical forest ecosystems globally. Measurements of hydrology and meteorology span decades, and currently include temperature, humidity, precipitation, cloud base level, throughfal...

The origins of the Luquillo Long Term Ecological Research Program are traced through four historical trends that still influence research activity in Puerto Rico’s Luquillo Mountains: (1) A history of identifying lands for protection and their designation for public uses; (2) A history of governmental and non-governmental institutions acting with the foresight to pursue scientific research for the benefit of economic development and the will to support scientific activity; (3) The uninterrupted progression of scientific activity through projects and programs that cumulatively developed a...

Understanding the complex and unpredictable ways ecosystems are changing and predicting the state of ecosystems and the services they will provide in the future requires coordinated, long-term research. This paper is a product of a U.S. National Science Foundation funded Long Term Ecological Research (LTER) network synthesis effort that addressed anticipated changes in future populations and communities. Each LTER site described what their site would look like in 50 or 100 yr based on long-term patterns and responses to global change drivers in each ecosystem. Common themes emerged and...

Although past land use effects on composition and structure are described for many forest types, forested riparian areas have been overlooked. Riparian areas may contain unique species and high species richness, as well as contribute basal leaf-litter resources for aquatic fauna. We asked: Does past land use alter composition in riparian versus upland areas in wet tropical forest? Which vegetation life-forms characterize riparian zones? What is the composition and quantity of leaf-litter in riparian zones compared to uplands? Location Riparian and upland locations in tropical wet forest,...

Cloud forest species face many threats including, but not limited to, climate change and increased extreme weather events. On September 20th, 2017, Hurricane Maria hit the island of Puerto Rico, changing the amount of coverage, structure, and microclimate of its forests. Cloud forest epiphytes can be particularly susceptible to such dramatic changes. Following Hurricane Maria, we studied the leaf characteristics potentially associated with reduced leaf health in the Lepanthes woodburyana, an epiphytic micro-orchid, endemic to Puerto Rico. We specifically assessed whether the environmental...