Treesearch

Wildfires can dramatically modify the hydrologic and erosion response of ecosystems, increasing risks to population and assets downslope of fire affected hillslopes. This applies especially to volcanic areas in fire-prone regions which often exhibit steep terrain and high population densities. However, the effects of fire on key hydrologic and erosion parameters, which are critical for modelling runoff-erosion processes, predicting related post-fire risks and for selecting effective mitigation measures, have not been extensively assessed in this terrain type. Here we evaluate water erosion...

On dryland hillslopes, vegetation water availability is often subsidized by the redistribution of rainfall runoff from bare soil (sources) to vegetation patches (sinks). In regions where rainfall volumes are too low to support spatially continuous plant growth, such functional connectivity between bare soil and vegetated areas enables the establishment and persistence of dryland ecosystems. Increasing the connectivity within bare soil areas can intensify runoff and increase water losses from hillslopes, disrupting this redistribution and reducing the water available to sustain ecosystem...

Wild pigs (Sus scrofa), which are invasive in many regions globally, can alter ecosystems and compete with native species through interference competition and resource exploitation. Wild pig impacts on other species may increase with greater niche overlap, which could vary over time based on environmental conditions, resource availability, or biological traits like diet, especially as seasonal variation in wild pig diet has been widely documented. A limited number of studies have assessed spatial or temporal overlap between native species and invasive wild pigs, with only a handful...

Understanding whether invasive and native species compete for shared resources where they co-occur is essential for mitigating the negative impacts of invasive species on native ecosystems. Here, we examined how the presence and density of an invasive species, wild pigs (Sus scrofa), affect native white-tailed deer (Odocoileus virginianus; hereafter, deer) on the Savannah River Site, SC, USA. We examined potential changes in deer areas of use, temporal overlap, and occupancy to evaluate the effects of wild pig occurrence and density on deer space use, diel activity, and co-occurrence with...

Lead mining in the Southeast Missouri Lead Mining District began in the 1700s and continued for nearly 300 years; the waste piles associated with smelting, mining, and milling of lead ores have released metal residues that have contaminated soil and water in the region. Previous studies in the district have indicated potential harm to wildlife, including birds, because of elevated lead concentrations associated with mining. Exposure to soil-borne lead was correlated with elevated lead concentrations in tissues, inhibition of δ-aminolevulinic acid dehydratase (δALAD), and renal lesions in...

Accurate observation of hillslope groundwater storage and instantaneous recharge remains difficult due to limited monitoring and the complexity of mountainous landscapes. We introduce a novel storage-discharge method to estimate hillslope recharge and the recharge ratio—the fraction of precipitation that recharges groundwater. The method, which relies on streamflow data, is corroborated by independent measurements of water storage dynamics inside the Rivendell experimental hillslope at the Eel River Critical Zone Observatory, California, USA. We find that along-hillslope patterns in...

While tree plantations have increased globally, there is growing interest in restoring plantations to native ecosystems. Restoration efforts may be more successful when tree species native to original ecosystems are planted instead of species that are either introduced or native, but off site. Plantations of red pine (Pinus resinosa Ait.) in the western Great Lakes region of North America were commonly established on red pine sites, often after agricultural clearing and abandonment. Red pine is the only species in the overstory, compared to 10 or more species in red pine woodlands....

Invasive exotic plants are one of the most challenging problems facing forest land managers. Manyinvasive species are shade intolerant and typically do not nvade forest sites with dense tree canopies. In contrast, Asiatic bittersweet (Celastrus orbiculatus Thunb.), a shade-tolerant exotic liana, is capable of colonizing and successfully growing in forest sites and has proven to be an aggressive competitor of native vegetation in the eastern USA. We investigated changes in the presence and cover of bittersweet after a hurricane-created major canopy disturbance in a southeastern USA upland...

BACKGROUND Trapping is commonly used as the primary management tool in attempts to reduce invasive wild pigs (Sus scrofa), but traditional trapping techniques are often ineffective. However, recently developed traps permit the capture of entire social groups (sounders) of wild pigs, and the strategy of whole-sounder removal may achieve more effective control. Our objective was to experimentally compare traditional control (TC; primarily traditional trapping, but including hunting with dogs, and opportunistic shooting) and whole-sounder removal (WSR) strategies by assessing density reduction...

Active management for promoting oaks (Quercus spp.) and restraining maples (Acer spp.) is mostly conducted in public forests (e.g., national forests [NF] and state forests [SF]) because of oaks' ecological and economic importance. Studies have shown that current management efforts have limited success, meanwhile, oakdominant forests continue to shift in composition and structure to shade-tolerant, fire-sensitive mesophytic species (e.g., red maple A. rubrum). It remains to be evaluated whether current management can achieve its objectives in public forests and at regional scales. In this...