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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...

Anthropogenic activities can alter natural disturbance regimes in ecosystems, and thereby affect the structure and function of biological diversity. As many of the world’s ecosystems are degraded beyond natural recovery, well-defined restoration goals are necessary to maintain the ecological processes that provide valuable ecosystem services. Utilizing both taxonomic and functional approaches, we investigate the impacts of forest management practices in structuring predator communities in pine forest ecosystems under different forest management regimes. We focus on snakes as an indicator...

Twenty years of monitoring data are assessed for trends in abundance of running buffalo clover (Trifolium stoloniferum), an endangered species found on the Fernow Experimental Forest in northeastern West Virginia, where the clover is found under various forest management intensities. Monitored locations were grouped for analysis into sites with common disturbance histories. Of the 13 sites, about half (46%, six sites) were found to have statistically significant trends between numbers of rooted crowns and time. Three out of eight sites with recent and sustained periodic disturbance showed...

Degraded red spruce (Picea rubens)-northern hardwood ecosystems are the focus of restoration efforts across high-elevation landscapes in the Central Appalachian region of the eastern United States. To promote ecosystem function and long-term sustainability of restored forests, it is important to understand the associated biota, including bird communities. Certain bird species could serve as ecological indicators, with potential applications for evaluating restoration efforts. However, contemporary and statistically rigorous studies of red spruce bird communities in this region are lacking,...

While it is known that modifying the hydroxyls in wood can improve the decay resistance; what is often missing in the literature is whether these modifications alter wood nanostructure, and how these changes correlate to the improved decay resistance. Here, we used small angle neutron scattering (SANS) to probe the effects of alkylene oxide modifications on wood nanostructure. Southern pine wood samples were chemically modified to various weight percentage gains (WPG) using four different alkylene oxides: propylene oxide (PO), butylene oxide (BO), epichlorohydrin (EpH), and epoxybutene...

Experiments show that elevated atmospheric CO2 (eCO2) often enhances plant photosynthesis and productivity, yet this effect varies substantially and may be climate sensitive. Understanding if, where and how water supply regulates CO2 enhancement is critical for projecting terrestrial responses to increasing atmospheric CO2 and climate change. Here, using data from 14 long-term ecosystem-scale CO2 experiments, we show that the eCO2 enhancement of annual aboveground net primary productivity is sensitive to annual precipitation and that this sensitivity differs between woody and grassland...

Promoting sustainability of ecosystems and economic development is a dual national objective in China, as well as one of the sustainable development goals (SDGs) of the United Nations. The Three-River Headwaters Region, where a National Park initiative has been initiated in the pastoral region of the Qinghai-Tibetan Plateau, is one of the key pilot projects in China with sustainability targets for 2025 and 2035. This paper assesses the possibility of achieving established targets for the proportion of cultivated to available grassland. These targets consider both ecosystem protection and...

This study was aimed at improving the gas barrier property of sugarcane based LLDPE using cellulose nanocrystals (CNCs). Specifically, this study evaluated the effect of CNC content on the crystallinity, tortuosity factor, carbon dioxide permeability (PCO2), and/or oxygen permeability (PO2) of bio-LLDPE sheets and films. All nanocomposites showed considerable improvement in gas barrier irrespective of the CNC content. The PCO2 coefficient of LLDPE sheets decreased by 36% by adding 10 wt% of CNCs into the sheet. Similarly, a significant decline in both PO2 (about 50%) and PCO2 (about 33%)...

Wildfires can significantly impact air quality and human health. However; little is known about how different fuel bed components contribute to these impacts. This study investigates the air quality impacts of duff and peat consumption during wildfires in the southeastern United States; with a focus on the differing contributions of fine particulate matter less than 2.5 µm in size (PM2.5) and ozone (O3) to air quality episodes associated with the four largest wildfire events in the region during this century. The emissions of duff burning were estimated based on a field measurement of a...

Numerous devastating air pollution events from wildfire smoke occurred in this century in the western USA, leading to severe environmental consequences. This study projects future fire emissions in this region under climate change with a focus on comparing the relative contributions from future changes in burned area, fuel loading and fuel moisture. The three properties were projected using an empirical fire model, a dynamical global vegetation model and meteorological conditions respectively. The regional climate change scenarios for the western USA were obtained by dynamical downscaling...