Treesearch

Glacier retreat is projected to drive major shifts in the hydrology of many high‐elevation and high‐latitude watersheds. In particular, future decreases in glacier runoff are hypothesized to reduce the stability of hydro‐biogeochemical export. We test this hypothesis using a decade of discharge, dissolved organic carbon, total dissolved nitrogen and soluble reactive phosphorus data from four Alaskan watersheds spanning a gradient in glacier cover. We demonstrate that glacier decline leads to lower and more variable runoff across years, with 2.6–4.3 times greater interannual variability in...

Recent fire activity across forests west of the Cascade Crest in Oregon and Washington (the “westside”) has increased interest in the region's historical fire regimes. Substantial spatial information exists describing the location, extent, and timing of historical fires in the region, but these records represent independent efforts at local-to-regional scales, with considerable variation in data resolution, methodologies, discoverability, and metadata. To address the need for a systematic dataset of historical westside fire, we compiled a spatial database of over 7,300 fire perimeters and...

The first efforts to restore red spruce (Picea rubens) ecosystems in the central and southern Appalachians began nearly 100 years ago, following broad scale declines that resulted from industrial logging activities and associated wildfires. While many localized efforts have occurred over the last century, the scale of red spruce restoration has dramatically increased over the last two decades. In the mid-2000s, the Central Appalachian Spruce Restoration Initiative (CASRI) was formed to bring restoration partners together, followed by establishment of the Southern Appalachian Spruce...

Increasing wildfire severity is driving interest in new land management approaches that can reduce fuels while also remaining feasible within land governance systems. Targeted grazing (TG), the practice of using livestock to manage vegetation, is one potential tool that can be integrated with other strategies to increase wildfire resilience. However, adoption of TG often requires action by public lands managers in complex institutional environments. We quantitatively tested a conceptual framework that integrates the theory of planned behavior and adaptive governance to evaluate factors...

Spanish juniper, Juniperus thurifera L, forests are typically managed as uneven-aged forests in the Iberian range, which requires information about site index (SI) classes and diameter at breast height (dbh) distributions. The objective of this study is to evaluate and compare the performance of remote sensing models using multitemporal airborne laser scanning (ALS) data, Landsat metrics of state and change along with topographic, geographic and climatic predictors for the prediction of SI classes and diameter distributions. The best model for SI classes was a logistic model that showed an...

Forest inventory and monitoring is critically important to the long-term success of forest ecosystems, particularly given increasing levels of disturbance from wildfire, insects, disease, and human activity. Since its inception under the McSweeney-McNary Forest Research Act of 1928, and following revisions in the 1998 Agricultural Research, Extension, and Education Reform Act and 2014 Agricultural Act (“Farm Bills”), the U.S. Department of Agriculture (USDA) Forest Service Forest Inventory and Analysis (FIA) program has conducted continuous monitoring of the Nation’s forest resources,...

Domestic animals represent the largest mammalian biomass on Earth, creating an urgent need to understand their effects on native species. Environmental change may further alter these interactions, particularly for large herbivores that are highly sensitive to climate‐driven resource availability.Interactions among assemblages of large herbivores include interference and exploitation competition, but the grazing optimization hypothesis paradigm suggests that interactions are often facilitative because defoliation from grazing stimulates compensatory regrowth of high‐quality forage that...

Biological nitrogen (N) fixation (BNF) provides the N needed to produce proteins and other biological building blocks, helping feed humanity and mitigate climate change. Due to its high energetic cost compared to other forms of N acquisition, biotic investment in BNF indicates N limitation. Globally gridded BNF flux data provide an opportunity to determine the energetic investment in BNF across ecosystems, which would help reconcile conflicting indicators of N limitation. Here, we use a new BNF synthesis to quantify the relative importance of BNF in different N‐fixing niches, in different...

Wildfires, unplanned fires that start and spread under the influence of weather and fuel composition, are increasing in frequency, duration, and severity across North America. While wildfires are one component of wildland fire, a broader natural process in many ecosystems, their changing behavior poses growing ecological and management challenges. Although wildfire is widely recognized as an important disturbance, empirical research quantifying its impacts on freshwater ecosystems remains limited and fragmented. As a result, our understanding of how wildfire affects imperiled freshwater...

We introduce a fully nonparametric estimator to estimate willingness to pay (WTP) using contingent valuation (CV) data. Traditional methods such as the probit model are used because of their roots in utility theory as well as their ease to implement. However, they are limited by their reliance on strict parametric assumptions, such as linearity and the requirement that the researcher pre‐select important covariates. While these methods are widely used, they may fail to capture complex relationships, particularly in situations involving nonlinearity or interactions among variables. This...