Treesearch

Losses in crop yield due to invasive insects, weeds, pathogens, and herbivores cost trillions of dollars per year globally. To prevent further spread of invasive agricultural pest species, continuous monitoring and prevention are crucial. Once introduced, however, assessing the impact of an invasive pest on agricultural production and testing management strategies are essential. The green iguana (Iguana iguana), a globally widespread invasive herbivore, is considered a possible agricultural pest although no quantitative data on its impact are available. In this study, we evaluated the...

The Amazon forest contains globally important carbon stocks, but in recent years, atmospheric measurements suggest that it has been releasing more carbon than it has absorbed because of deforestation and forest degradation. Accurately attributing the sources of carbon loss to forest degradation and natural disturbances remains a challenge because of the difficulty of classifying disturbances and simultaneously estimating carbon changes. We used a unique, randomized, repeated, very high-resolution airborne laser scanning survey to provide a direct, detailed, and high-resolution partitioning...

Plant litter decomposition is driven by soil biota and biophysiochemical conditions as well as substrate quality. Prescribed burns can affect the abundance and diversity of soil arthropods and the biophysiochemical conditions in terrestrial ecosystems. In this study, we examined the effects of a prescribed burn on soil arthropods and litter chemistry in decomposing litter during a total of 469-days field incubation using litter from two grasses, Dichanthium annulatum and Megathyrsus maximus, in a subtropical moist pastureland of Puerto Rico. We found the prescribed burn substantially...

Knowledge of space use provides insight into a species’ habitat requirements needed for conservation. Little is known about space use of the near threatened Kirtland’s Warbler (Setophaga kirtlandii) wintering in The Bahamas, and how the warbler’s home range size and core area overlap among individuals and vary with sex and age, food availability, winter season, and habitat characteristics. To address these knowledge gaps, we used radio telemetry to determine sedentary home range size (95% adaptive kernel), core area (50% AK), and overlap for 27 radio-tagged warblers during two winters on...

During the 2015–2016 El Niño, the Amazon basin released almost one gigaton of carbon (GtC) into the atmosphere due to extreme temperatures and drought. The link between the drought impact and recovery of the total carbon pools and its biogeochemical drivers is still unknown. With satellite‐constrained net carbon exchange and its component fluxes including gross primary production and fire emissions, we show that the total carbon loss caused by the 2015–2016 El Niño had not recovered by the end of 2018. Forest ecosystems over the Northeastern (NE) Amazon suffered a cumulative total carbon...

Nitrous oxide (N2O), a greenhouse gas with ozone destruction potential, is mitigated by the microbial reduction to dinitrogen catalyzed by N2O reductase (NosZ). Bacteria with NosZ activity have been studied at circumneutral pH but the microbiology of low pH N2O reduction has remained elusive. Acidic (pH < 5) tropical forest soils were collected in the Luquillo Experimental Forest in Puerto Rico, and microcosms maintained with low (0.02 mM) and high (2 mM) N2O assessed N2O reduction at pH 4.5 and 7.3. All microcosms consumed N2O, with lag times of up to 7 months observed in microcosms with...

This perspective emerged from ongoing dialogue among ecologists initiated by a virtual workshop in 2021. A transdisciplinary group of researchers and practitioners conclude that urban ecology as a science can better contribute to positive futures by focusing on relationships, rather than prioritizing urban structures. Insights from other relational disciplines, such as political ecology, governance, urban design, and conservation also contribute. Relationality is especially powerful given the need to rapidly adapt to the changing social and biophysical drivers of global urban systems....

Tropical storms cause a range of short-, medium-, and long-term effects on forest ecosystems; they influence forest structure, dynamics, composition, and diversity of biota, as well as the abiotic component that supports ecosystem processes and functions. Storms also affect the provision of ecosystem services that are vital to sustain life and necessary to support ecosystem functions. The passage of atmospheric systems also provides opportunities to conduct studies allowing knowledge production, thus broadening understanding of these disturbances on forest ecosystems. Tropical storms over...

The USFS Geospatial Technology and Applications Center (GTAC) and the International Institute of Tropical Forestry partnered to develop a workflow that produces high-resolution tree canopy cover data using available lidar data and USFS Enterprise software. GTAC implemented this workflow across 2016 and 2018 lidar data acquisitions for Puerto Rico and US Virgin Islands, resulting in 1 meter spatial resolution tree canopy cover data. This publication documents the workflow used to create this datasets and presents percent canopy cover for Puerto Rico and the US Virgin Islands.

The built environment includes human-made or modified landscapes, structures, and infrastructure systems that bring together people, services, and economic activities. This chapter focuses on the built environment found in and around cities and suburbs across the country, where most Americans live and work. Cities and urban areas are also a key part of the country’s culture, nature, and historical heritage. The choices that we make today in cities, suburbs, and the built environment to address climate change will affect the livelihoods, well-being, and quality of life for all Americans in...