Treesearch

Woody tissue carbon (C) concentration is a key wood trait necessary for accurately estimating forest C stocks and fluxes, which also varies widely across species and biomes. However, coarse approximations of woody tissue C (e.g., 50%) remain commonplace in forest C estimation and reporting protocols, despite leading to substantial errors in forest C estimates. Here, we describe the Global Woody Tissue Carbon Concentration Database (GLOWCAD): a database containing 3,676 individual records of woody tissue C concentrations from 864 tree species. Woody tissue C concentration data—i.e., the...

Wildfires devastated communities in Oregon and Washington in September 2020, burning almost as much forest west of the Cascade Mountain crest (“the westside”) in 2 weeks (~340,000 ha) as in the previous five decades (~406,00 ha). Unlike dry forests of the interior western United States, temperate rain forests of the Pacific Northwest have experienced limited recent fire activity, and debates surrounding what drove the 2020 fires, and management strategies to adapt to similar future events, necessitate a scientific evaluation of the fires. We evaluate five questions regarding the 2020 Labor...

No common global definition exists of urban populations, resulting in a lack of shared standards across countries for equivalent comparisons. Therefore, I used global population models of Landscan, Worldpop, and Gridded Population of the World to generate a provisional classification of population density classes to define urban and rural by human population densities, which is an enduring attribute to differentiate urban lands from rural lands. I calibrated 2015 population density models to the United Nations 2015 global urban population estimate of 53.9% and then balanced among the...

White pines (Pinus, subgenus Strobus) in North America are highly vulnerable to the native mountain pine beetle (Dendroctonus ponderosae), invasive white pine blister rust (Cronartium ribicola), and consequences of altered disturbance regimes, with sugar pine (Pinus lambertiana) being among the most in peril. Radial thinning treatments reflect an effort to balance the needs of late seral, high forest cover for some wildlife species with the desire to also promote habitat for species requiring higher light and lower competition, as well as to create heterogenous forest structure that can be...

Forest and nonforest ecosystems of the western United States are experiencing major transformations in response to land-use change, climate warming, and their interactive effects with wildland fire. Some ecosystems are transitioning to persistent alternative types, hereafter called “vegetation type conversion” (VTC). VTC is one of the most pressing management issues in the southwestern US, yet current strategies to intervene and address change often use trial-and-error approaches devised after the fact. To better understand how to manage VTC, we gathered managers, scientists, and practition...

Water availability and other site conditions influence poplar biomass productivity and affect clonal performance due to genotype × environment interactions. It is important to select genotypes with high water use efficiency (WUE) that maximizes yield with available amounts of water at sites, while avoiding drought stress and growth impacts to the trees. During drought, stomatal closure induces increased accumulation of δ13C carbon isotope in tree tissues, which is strongly correlated with WUE of trees and usually expressed through carbon isotope discrimination (Δ). Our primary objectives...

The wildland–urban interface (WUI) is the focus of many important land management issues, such as wildfire, habitat fragmentation, invasive species, and human–wildlife conflicts. Wildfire is an especially critical issue, because housing growth in the WUI increases wildfire ignitions and the number of homes at risk. Identifying the WUI is important for assessing and mitigating impacts of development on wildlands and for protecting homes from natural hazards, but data on housing development for large areas are often coarse. We created new WUI maps for the conterminous United States based on...

The WEPPcloud interface is a new online decision-support tool for the Water Erosion Prediction Project (WEPP) model that facilitates data preparation and model runs, and sum- marizes model outputs into tables and maps that are easily interpretable by users. The interface can be used by land and water managers in United States, Europe, and Australia inter- ested in simulating streamflow, sediment and pollutant loads from both undisturbed and disturbed (e.g. post-wildfire or post-treatment such as thinning or prescribed fires) forested watersheds. This article contains full hydrologic model...

Suspended sediment and nutrients following forest management activities or wildfires are transported to streams and lakes via surface runoff and are a major threat to water quality. Land and water managers resort to hydrologic models to test hypotheses that can help them make informed decisions to minimize disturbances and protect water resources. We present applications of an online interface, WEPPcloud, for the Water Erosion Prediction Project (WEPP) model as a pre- and post-disturbance management tool to model various gauged and ungauged forested watersheds throughout the western U.S....

Historically, grasslands with limited tree presence were embedded in a matrix of predominantly open oak and pine forests in the eastern United States. These open ecosystems mostly have been lost to other land uses, particularly agriculture, and also to closed forests under fire exclusion because frequent surface fire prevents tree encroachment. We located the potential extent of eastern fire-maintained grasslands by applying the random forests and C5.0 classifiers to determine the relationship between mapped areas of historical grasslands and topography and wind speed, which are proxies...