Treesearch

Streams and rivers of the Luquillo Experimental Forest, Puerto Rico, have been the subject of extensive watershed and aquatic research since the 1980s. This research includes understanding stream export of nutrients and coarse particulate organic matter, physicochemical constituents, aquatic fauna populations and community structure. However, many of the streams and watersheds studied do not appear in standard scale maps. We document recent collaborative and multi-institutional work to improve hydrological network information and identify knowledge gaps. The methods used to delimit and...

The soil is an important resource for several ecosystem and biosphere processes. Yet, soil biology is challenged with the identification of many and diverse species and to understand the specific role organisms play, how they are organized, and how they respond to changing environmental conditions. Within this context, there is no universal tool or method that can be applied to a comprehensive study of all the soil and litter fauna that can be found across all soil types and environmental conditions around the globe. Thus, the type of sampling system used for any soil investigation must be...

The phylogenetic and functional diversity of microbial communities in tropical rainforests, and how these differ from temperate communities remain poorly described but are directly related to the increased fluxes of greenhouse gases such as nitrous oxide (N2O) from the tropics. Towards closing these knowledge gaps, we analyzed replicated shotgun metagenomes representing distinct life zones from four locations in the Luquillo Experimental Forest (LEF), Puerto Rico. These soils had a distinct microbial community composition and lower species diversity when compared to temperate grasslands or...

Reduction in faunal diversity is suggested to reduce litter decomposition, whereas increases in ultraviolet (UV) radiation may directly enhance or indirectly retard litter decomposition. Here we examined the effect of soil arthropods and UV radiation on litter decomposition in burned and unburned plots during a 469-day field experiment in a subtropical pastureland of Puerto Rico. Prescribed burn reduced soil arthropod diversity and increased UV radiation during the initial period of 240 days following the burn, and consequently reduced plant litter decomposition. The density of predators...

This paper describes the challenges and potential opportunities for using renewable electricity technologies to increase the resilience of Puerto Rico’s food supply system (including commodity production, processing, storage, and distribution) to prolonged (2 days to 6 months) utility power outages. This need is essential because the island’s grid electricity has proven to be very susceptible to long-run outages related to severe weather and geologic events (e.g., Hurricanes Irma and Maria in 2017 and earthquakes in 2019 and 2020) as well as outages related to aging and poorly maintained...

Este informe describe los desafíos y posibilidad de oportunidades para el uso de tecnologías de electricidad renovable para aumentar la resiliencia del sistema de suministros de alimento de Puerto Rico (incluida la producción, el procesamiento, el almacenamiento y la distribución de productos básicos) ante interrupciones prolongadas (de 2 días a 6 meses) de energía eléctrica. Esta necesidad es esencial porque la red eléctrica de la isla ha demostrado ser muy susceptible a interrupciones a largo plazo relacionadas con eventos climáticos y geológicos severos (por ejemplo, los huracanes Irma...

In this study, water level models are constructed to characterize mangrove flooding across urban gradients in Puerto Rico. The most urban sites exhibited 95% longer hydroperiods, 23% lower flood frequencies, and 110% lower depths than the least urban sites. Rainfall importance was explained more by geomorphology and tidal connectivity than by urbanization, but there was evidence for changes in tidal amplitudes along the urban gradient. Relationships between surface water chemical metrics and land cover contradicted previous studies by suggesting lower nutrients and biochemical oxygen...

This study characterizes the structure and composition of mangrove forests across urban gradients in Puerto Rico. It then uses a suite of hydrologic, water chemistry, and land cover variables to test for the relative importance of urban intensity alongside flooding and water chemistry in explaining observed variability in forest structure and composition. Three separate statistical tests suggest a significant but limited influence of urbanness on forest composition and structure. In the most urban sites, the diameters of the largest trees were 27% larger, but all structural measurements...

There is increasing enthusiasm around the concept of soil health, and as a result, new public and private initiatives are being developed to increase soil health-related practices on working lands in the United States. In addition, billions of U.S. public dollars are dedicated annually toward soil conservation programs, and yet, it is not well quantified how investment in conservation programs improve soil health and, more broadly, environmental health. The Environmental Quality Incentives Program(EQIP) is one of the major U.S. public conservation programs administered on privately managed...