Treesearch

Over the past century the size and severity of wildfires, as well as post-fire recovery processes (e.g., seedling establishment), have been altered from historical levels due to management policies and changing climate. Tree seedling establishment and growth drive future overstory tree dynamics after wildfire. Post-fire tree regeneration can be highly variable depending on burn severity, pre-fire forest condition, tree regeneration strategies, and climate; however, few studies have examined how different abiotic and biotic factors impact seedling density and growth and the interactions...

As wildland fires amplify in size in many regions in the western USA, land and water managers are increasingly concerned about the deleterious effects on drinking water supplies. Consequences of severe wildfires include disturbed soils and areas of thick ash cover, which raises the concern of the risk of water contamination via ash. The persistence of ash cover and depth were monitored for up to 90 days post-fire at nearly 100 plots distributed between two wildfires in Idaho and Washington, USA. Our goal was to determine the most ‘cost’ effective, operational method of mapping post-wildfire...

There is increasing demand in environmental remediation and other sectors for specialized sorbents made from renewable materials rather than hard coals and minerals. The proliferation of new pyrolysis technologies to produce bio-based energy, fuels, chemicals, and bioproducts from biomass has left significant gaps in our understanding of how the various carbonaceous materials produced by these systems respond to processes intended to improve their adsorption properties and commercial value. This study used conventional steam activation in an industrial rotary calciner to produce activated...

The rate of global climate change is projected to outpace the ability of many natural populations and species to adapt. Assisted migration (AM), which is defined as the managed movement of climate-adapted individuals within or outside the species ranges, is a conservation option to improve species' adaptive capacity and facilitate persistence. Although conservation biologists have long been using genetic tools to increase or maintain diversity of natural populations, genomic techniques could add extra benefit in AM that include selectively neutral and adaptive regions of the genome. In...

One of the largest impacts on forest soils, apart from logging disturbances, is wildfire. The physical disturbances include suppression activities, post-fire erosion during storm events, and slope failures. Biological and chemical disruptions to soil functioning can occur as well. Since soils are the key to site productivity and sustainability, conservation of soil resources in the post-wildfire environment are of the utmost importance. Some soil conservation measures can be employed during fire suppression as Best Management Practices conservation. The bulk of these activities fall into...

The increasing incidence of wildfires across the southwestern United States (US) is altering the contemporary forest management template within historically frequent-fire conifer forests. An increasing fraction of southwestern conifer forests have recently burned, and many of these burned landscapes contain complex mosaics of surviving forest and severely burned patches without surviving conifer trees. These heterogeneous burned landscapes present unique social and ecological challenges. Severely burned patches can present numerous barriers to successful conifer regeneration, and often...

Quantifying forest understory biomass is important for understanding ecological processes, but there are few methods for non-destructive measurement of understory biomass in southeast Alaska. We developed cover-to-biomass equations for common understory species in young-growth Sitka spruce (Picea sitchensis)–western hemlock (Tsuga heterophylla) forests. A sampling method of visually estimating cover and destructively measuring biomass was used at 35 stands aged 10 to 67 years on Prince of Wales Island in southeast Alaska from 2007 to 2018. Linear cover to biomass regressions were fitted...

The coordination of plant leaf water potential (ΨL) regulation and xylem vulnerability to embolism is fundamental for understanding the tradeoffs between carbon uptake and risk of hydraulic damage. There is a general consensus that trees with vulnerable xylem more conservatively regulate ΨL than plants with resistant xylem. We evaluated if this paradigm applied to three important eastern US temperate tree species, Quercus alba L., Acer saccharum Marsh. And Liriodendron tulipifera L., by synthesizing 1600 ΨL observations, 122 xylem embolism curves and xylem anatomical measurements across 10...

Land management and fire management goals are increasingly framed in terms of resilience, in part due to the combined impacts of climate change, land-use change, and legacies of land management. Implicit in this framing is the recognition that resilience to wildfire involves both ecological and social dimensions. Discussions surrounding resilience often do not explicitly articulate what resources should or must be resilient to wildfire, and seldom do they make explicit for whom resilience is important. Land managers need to understand and identify which resources their communities want to...

Conserving soil carbon (C) and harnessing the potential for soil C sequestration requires an improved understanding of the processes through which organic material accumulates in soil. Currently, competing hypotheses exist regarding the dominant mechanisms that control soil C accumulation and transfers to mineral-associated pools. Long-standing hypotheses rely upon an assumed strong relationship between the quantity of organic inputs and soil C accumulation, while more recent hypotheses have shifted the focus towards the more complex controls of root activity, microbial processing and...