Treesearch

Body size is among the key subjects in macroecology and macroevolution with important implications for conservation. Two major rules have been proposed to explain how body size changes over evolutionary time (Cope's rule) and across temperature gradients (Bergmann's rule). To date, however, the applicability of both rules to global terrestrial vertebrates (tetrapod) remains elusive. Here, using the newly available data, we comparatively examined the temporal variation in species body size of the world's extant tetrapod species (tetrapoda as a whole) and of each class, amphibians (Amphibia),...

The primary objective of this research was to propose a new methodology for calculating design flows in ungauged catchments, addressing uncertainties associated with outdated empirical formulas. Focusing on four catchments in the eastern USA, the methodology comprises two main steps: (1) determination of peak flow series using the EBA4SUB rainfall-runoff model and (2) calculation of design flows based on the generated series from EBA4SUB, utilizing the best-fitted statistical distribution. Linear scaling was applied to reduce the percent bias (PBIAS) error in design flows. The study...

Substantial portions of grassland are being converted to managed forest in Uruguay. Long-term paired watershed studies in other continents indicate that water yields from managed forest lands are reduced compared to grasslands. Few such studies have been conducted in South America. This paired watershed study was initiated in 2000 to determine the hydrologic impacts of changing land use from grassland to pine plantation in Uruguay. Outflow rates, water table depths, rainfall, and meteorological variables were continuously measured for a 20-year period on two adjacent watersheds, LC1 (69...

The U.S. Department of Agriculture, Forest Service has established and maintains experimental forests and ranges across the United States and Puerto Rico; these forests are a cornerstone of the Agency’s research program. This technical report provides a characterization of the soils on 19 experimental forests in the Southeastern United States that are managed by the Forest Service, Southern Research Station (SRS). This initiative was sponsored through the SRS Experimental Forest and Range Network to enhance the basis for research, demonstration and education activities, and collaborations....

Prescribed fire has emerged as an essential ecosystem management practice for maintaining forest health and mitigating wildfire risks. However, its spatio-temporal patterns and potential impacts on water quantity and quality remain poorly understood compared to those of wildfires. By analyzing the Monitoring Trends in Burn Severity database (1984–2022), we characterized distinct regional, seasonal and interannual dynamics of large prescribed fires relative to wildfires across the conterminous United States. We found the Southeast dominated the national prescribed fire regime, accounting...

Nepal is highly vulnerable to severe soil erosion driven by monsoonal rainfall and rugged terrains. Limitations in ground observation networks have hindered comprehensive, high-resolution national assessment of precipitation and rainfall-runoff erosivity (R-factor) across Nepal. This study systematically evaluated eight global gridded precipitation datasets (GPDs) against data from 152 weather stations, identifying the optimal precipitation dataset (TPHiPr) representing Nepal’s complex topography. Based on this high-quality dataset, we provided the first independent, long-term (1979–2020),...

Forest production chains grounded on applicable laws and regulations are essential for achieving sustainable forestry, circular economies, and climatic mitigation. In Puerto Rico, reactivating the forestry sector as a key player capable of providing ecosystem services, raw materials, and products can signficantly contribute to these goals through the sustainable development of local wood production. However, the lack of wood processing capacity and active managementfor forest products became evident following the hurricanes Irma and María in 2017, which downed large quantities of trees....

Microbial nitrogen (N) fixation accounts for c. 97% of natural N inputs to terrestrial ecosystems. These microbes can be free-living in the soil and leaf litter (asymbiotic) or in symbiosis with plants. Warming is expected to increase N-fixation rates because warmer temperatures favor the growth and activity of N-fixing microbes.We investigated the effects of warming on asymbiotic components of N fixation at a field warming experiment in Puerto Rico. We analyzed the function and composition of bacterial communities from surface soil and leaf litter samples.Warming significantly increased...

Accurately monitoring forest canopy height is crucial for sustainable forest management, particularly in southeastern North Carolina, USA, where dense forests and limited accessibility pose substantial challenges. This study presents an explainable machine learning framework that integrates sparse GEDI LiDAR samples with multi-sensor remote sensing data to improve both the accuracy and interpretability of forest canopy height estimation. This framework incorporates multitemporal optical observations from Sentinel-2; C-band backscatter and InSAR coherence from Sentinel-1; quad-polarization...

Convolutional neural networks (CNNs), specifically U-Nets, successfully detect and segment individual tree crowns when applied to high spatial resolution remotely sensed data. However, much of the prior work for individual tree detection and segmentation has been in arid climates such as the western United States and the African Sahel. In this study, we used the U-Net-id CNN architecture and National Agriculture Imagery Program (NAIP) imagery to investigate forest-cover-specific training on individual tree crown detection in Virginia, U.S. We trained three models using hand-delineated...