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- Coastal wetlands are shrinking rapidly due to land-use activities. Accelerated sea-level rise (SLR) associated to the warming climate is also affecting coastal wetlands, particularly in islands with limited coastal plains.We analyzed coastal wetland changes in Puerto Rico by applying the Sea Level Affecting Marshes Model under two scenarios by 2100.We also analyzed mortality and recruitment in a freshwater swamp dominated by the tree Pterocarpus officinalis Jacq. in the context of landscape saltwaterintrusion and drought. Our results indicate mangroves and estuarine water would replace the...AuthorsMei Yu, Elsie Rivera-Ocasio, Tamara Heartsill Scalley, Daniel Davila-Casanova, Neftalí Rios-López, Qiong GaoSourceWetlandsYear2019
- Background: Fire is an important disturbance that influences species composition, community structure, and ecosystem function in forests. Disturbances such as hurricanes and landslides are critical determinants of community structure to Caribbean forests, but few studies have addressed the effect of paleofire disturbance on forests in Puerto Rico, USA. Soil charcoal is widely used to reconstruct fire history. However, the occurrence and frequency of paleofire can be underestimated due to charcoal decay. Results: We reconstructed the fire history of subtropical dry forests of Puerto Rico...AuthorsWei Huang, Xianbin Liu, Grizelle Gonzalez, Xiaoming ZouSourceFire EcologyYear2019
- The Normalized Difference Vegetation Index (NDVI) is one of the most commonly used vegetation indices for monitoring ecosystem dynamics and modeling biosphere processes. However, global NDVI products are usually provided with relatively coarse spatial resolutions that lack important spatial details. Producing NDVI timeseries data with high spatiotemporal resolution is indispensable for monitoring land surfaces and ecosystem changes, especially in spatiotemporally heterogeneous areas. The Improved Flexible Spatiotemporal DAta Fusion (IFSDAF) method was developed in this study to fill this...AuthorsMeng Liu, Wei Yang, Xiaolin Zhu, Jin Chen, Xuehong Chen, Linqing Yang, Eileen HelmerKeywordsSourceRemote Sensing of EnvironmentYear2019
- Forest degradation is common in tropical landscapes, but estimates of the extent and duration of degradation impacts are highly uncertain. In particular, selective logging is a form of forest degradation that alters canopy structure and function, with persistent ecological impacts following forest harvest. In this study, we employed airborne laser scanning in 2012 and 2014 to estimate three-dimensional changes in the forest canopy and understory structure and aboveground biomass following reduced-impact selective logging in a site in Eastern Amazon. Also, we developed a binary classificatio...AuthorsEkena Rangel Pinagé, Michael Keller, Paul Duffy, Marcos Longo, Maiza dos-Santos, Douglas MortonSourceRemote SensingYear2019
- Clouds persistently engulf many tropical mountains at elevations cool enough for clouds to form, creating isolated areas with frequent fog and mist. Under these isolated conditions, thousands of unique species have evolved in what are known as tropical montane cloud forests (TMCF) and páramo. Páramo comprises a set of alpine ecosystems that occur above TMCF from about 11° N to 9° S along the Americas continental divide. TMCF occur on all continents and island chains with tropical climates and mountains and are increasingly threatened by climate and land-use change. Climate change could...AuthorsEileen Helmer, E. A. Gerson, Scott Baggett, Benjamin Bird, Thomas S. Ruzycki, Shannon M. VoggesserSourcePLOS ONEYear2019
- There is a long history of experimental research in the Luquillo Experimental Forest in Puerto Rico. These experiments have addressed questions about biotic thresholds, assessed why communities vary along natural gradients, and have explored forest responses to a range of both anthropogenic and non-anthropogenic disturbances. Combined, these studies cover many of the major disturbances that affect tropical forests around the world and span a wide range of topics, including the effects of forest thinning, ionizing radiation, hurricane disturbance, nitrogen deposition, drought, and global...AuthorsTana E. Wood, Grizelle Gonzalez, Whendee Silver, Sasha Reed, Molly CavaleriKeywordsSourceForestsYear2019
- Understanding the population dynamics of migratory animals throughout the full annual cycle is critical for effective conservation, and requires knowing where populations are located throughout the year. For most Neotropical−Nearctic migratory bird species, breeding distributions are well-described, but less is generally known about their migratory paths, stopover areas, and wintering grounds. The Kirtland’s warbler Setophaga kirtlandii is an endangered longdistance migratory passerine with a restricted but well-described breeding distribution located primarily in Michigan (USA), with...AuthorsNathan W. Cooper, David N. Ewert, Joseph M. Wunderle Jr., Eileen Helmer, Peter P. MarraKeywordsSourceEndangered Species ResearchYear2019
- This article is a Commentary on Both et al., 221: 1853–1865.AuthorsMarcos Longo, Michael KellerKeywordsSourceNew PhytologistYear2019
- This Special Issue of Forests is based on papers presented at the 75th anniversary of the United States Department of Agriculture (USDA) Forest Service International Institute of Tropical Forestry as well as other papers relevant to the topic of the Special Issue. The Institute is but one leg of a conservation relay among cultures and institutions that began in Puerto Rico a millennium ago. The Institute began operations in 1939 and celebrated its 75th anniversary on May, 2014. Over its 75 years of operation, the Institute has focused its research on tropical forests, with the scope of the...AuthorsAriel Lugo, Grizelle GonzalezKeywordsSourceForestsYear2019
- Climate change is increasing the intensity of severe tropical storms and cyclones (also referred to as hurricanes or typhoons), with major implications for tropical forest structure and function. These changes in disturbance regime are likely to play an important role in regulating ecosystem carbon (C) and nutrient dynamics in tropical and subtropical forests. Canopy opening and debris deposition resulting from severe storms have complex and interacting effects on ecosystem biogeochemistry. Disentangling these complex effects will be critical to better understand the long-term implications...AuthorsOmar Gutiérrez del Arroyo, Whendee L. SilverKeywordsSourceGlobal Change BiologyYear2018