Treesearch

To test the hypothesis that wildfire smoke can cool summer river and stream water temperatures by attenuating solar radiation and air temperature, we analyzed data on summer wildfire smoke, solar radiation, air temperatures, precipitation, river discharge, and water temperatures in the lower Klamath River Basin in Northern California. Previous studies have focused on the effect of combustion heat on water temperatures during fires and the effect of riparian vegetation losses on postfire water temperatures, but we know of no studies of the effects of wildfire smoke on river or stream water...

Increasing evidence suggests that community-level responses to human-induced biodiversity loss start with a decrease of interactions among communities and between them and their abiotic environment. The structural and functional consequences of such interaction losses are poorly understood and have rarely been tested in real-world systems. Here, we analysed how 5 years of progressive, size-selective exclusion of large, medium, and small vertebrates and invertebrates - a realistic scenario of human-induced defaunation - impacts the strength of relationships between above- and belowground...

Fire regimes structure plant communities worldwide with regional and local factors, including anthropogenic fire management, influencing fire frequency and severity. Forests of the Rogue River Basin in Oregon, USA, are both productive and fire-prone due to ample winter precipitation and summer drought; yet management in this region is strongly influenced by forest practices that depend on fire exclusion. Regionally, climate change is increasing fire frequency, elevating the importance of understanding historically frequent-fire regimes. We use cross-dated fire-scars to characterize...

Understanding actual and potential selection on traits of invasive species requires an assessment of the sources of variation in demographic rates. While some of this variation is assignable to environmental, biotic or historical factors, unexplained demographic variation also may play an important role. Even when sites and populations are chosen as replicates, the residual variation in demographic rates can lead to unexplained divergence of asymptotic and transient population dynamics. This kind of divergence could be important for understanding long- and short- term differences among...

Wildfire increases the likelihood of runoff, erosion, and downstream sedimentation in many of the watersheds that supply water for Colorado’s Front Range communities. The objectives of this study were to: (1) identify rainfall intensity thresholds for a post-fire runoff or sediment delivery response at plots (≤0.06 ha), hillslopes (0.07–5.2 ha) and watersheds (100–1500 ha) after three Colorado Front Range wildfires for up to four years post-fire; (2) determine how the rainfall thresholds varied by fire location, year post-fire, spatial scale, and mulch treatments; and (3) use long-term...

Sourcing appropriate plant material for restoration within the heterogeneous landscape of southern California is a nuanced task further complicated by climate change. We generated species distribution models (SDMs) that may be useful tools for incorporating climate change scenarios into ecological restoration decisionmaking for southern California scrub and shrubland habitats. We modeled regional patterns of suitable habitat under baseline (1951–1980) and midcentury (2040–2069) climate conditions for 44 focal plant taxa under five future climate scenarios. Projected changes in habitat...

Enhanced understanding of subsurface water storage will improve prediction of future impacts of climate change, including drought, forest mortality, wildland fire, and strained water security. Previous research has examined the importance of plant‐accessible water in soil, but in upland landscapes within Mediterranean climates, soil often accounts for only a fraction of subsurface water storage. We draw insights from previous research and a case study of the Southern Sierra Critical Zone Observatory to define attributes of subsurface storage; review observed patterns in their distribution;...

Southern California chaparral environments, with steep mountain slopes, semi-arid climate, and non-cohesive soils, are very erosive landscapes. Wildfire is the dominant ecological disturbance event in chaparral and it greatly accelerates flooding and erosion, which are directly and/or indirectly related to the loss of the protective vegetation. Since the 1920s, dams and debris basins have been constructed by public works agencies to protect the growing population and infrastructure of southern California by intercepting and impounding flows of water and debris. Dams also capture stream...

Thousand Cankers Disease (TCD) affects Juglans and Pterocarya species. This disease poses not only a major threat to the nut and timber industries but also to native stands of walnut trees. Galleries created by Pityophthorus juglandis (vector) are colonized by the fungus Geosmithia morbida (causal agent of necrosis). It is unknown if other fungi colonizing these galleries might act antagonistically towards G. morbida. The objectives of this study were to: (1) characterize the fungal community associated with TCD-infected trees and (2) develop a pilot study addressing their potential...

Conifers are the dominant plant species throughout the high latitude boreal forests as well as some lower latitude temperate forests of North America, Europe, and Asia. As such, they play an integral economic and ecological role across much of the world. This study focused on the characterization of needle transcriptomes from four ecologically important and understudied North American white pines within the Pinussubgenus Strobus. The populations of many Strobusspecies are challenged by native and introduced pathogens, native insects, and abiotic factors. RNA from the needles of western...