Treesearch

Modifications to flow regimes may substantially alter the structure and function of aquatic systems and biotic assemblages. We assessed the impacts of relatively large dams in Alabama, USA, on fish assemblages and functional trait composition at two scales—within one drainage (Bear Creek, BCD) and between two drainages (BCD and Cahaba River, CRD). We collected fishes in shallow waters (< 1 m) of lotic sections of three impounded and two unimpounded streams. Impoundment effects were similar at both scales. Assemblage structure differed up-and downstream of impoundments, but few differences...

Nepal’s community forestry (CF) program, a globally recognized model of participatory forest management, relies on voluntary local leaders to guide forest management and governance decisions. Sustaining voluntary leadership has become increasingly challenging because of outmigration, declining forest dependence, and growing urban influence on rural livelihoods. In this study, we explore the values and motivations of existing leaders of community forest user groups (CFUGs), which underpin the leadership characteristics in sustaining these local institutions. We surveyed 144 leaders of 49...

This indicator reports value of capital investment and annual expenditure in forest management, wood and nonwood product industries, forest-based environmental services, recreation, and tourism. Investment in the forest sector, both in long-term capital projects and annual operating costs, is essential to sustain and improve the many ecosystem services that are derived from forests. The evaluation of capital investment indicators provides insights into the long-term and yearly expenses aimed at improving forest management, forest-related businesses, and the skills and knowledge of those...

The ecosystem services people associate with forests can be economic, environmental, social, and spiritual. Factors including regions, demographics, and changing environmental attitudes may influence the different ecosystem services that forests support (Brown and Reed 2000). This indicator report provides insight into the importance of forests to private woodland owners and visitors to U.S. Department of Agriculture (USDA), Forest Service national forests.

Non-native invasive plants cause significant ecological impacts to forests while requiring costly management interventions. We used data from Nationwide Forest Inventory plots to assess the extent and recent patterns of invasion by problematic non-native plants across United States forests at multiple scales (county, regional, and national). We estimated the proportion of forests that have been invaded and calculated the mean plot-level richness of invasive plant species during two recent inventory periods (ca. 2010 and 2018). We found that ∼99.5 million ha of forest have been invaded by...

Temperate grasslands such as the North American tallgrass prairie are among the most endangered terrestrial ecosystems due to changes in climate and land-use practices. While belowground responses of terrestrial ecosystems to perturbations have received greater attention in recent years, there is a dearth of long-term studies documenting changes over decadal scales. The current study addresses the long-term effects of fire (annual burning or fire exclusion), mowing, and nitrogen (N) and phosphorus (P) fertilization on the structure and composition of a tallgrass prairie nematode community...

The interfacial properties of the organic fraction of biomass burning aerosols (BBA), such as the critical micelle concentration (CMC) and surfactant composition, may vary based on the origin and moisture content of the fuel and the resulting combustion conditions. Surfactant composition, fraction of total particle mass, surface tension minimums, and CMC values of organics extracted from fresh and aged BBA produced using fuel beds from Georgia ecoregions (Piedmont, Coastal Plain, and Blue Ridge) and with fuel moisture contents representative of prescribed fires or drought-induced wildfires...

This study investigated the speciation and aqueous dissolution of macronutrients in fire ash from diverse ecosystems and speciation of ash and smoke from laboratory burning, exploring the variations and their causes. The speciation of phosphorus (P), calcium (Ca), and potassium (K) in fire ash from five globally distributed ecosystems was characterized by using X-ray absorption spectroscopy and sequential fractionation. Aqueous dissolution of the macronutrients was measured by batch experiments at acidic and alkaline pHs. The results showed that P existed mainly as Ca phosphates, Ca as...

The readership of ACS ES&T Air is undoubtedly familiar with the profound impacts of wildland-fire smoke on air quality and climate. It may be less familiar with the crucial role that wildland fires play in maintaining the ecological health of many forest types (McLauchlan et al., 2020). Wildland fires are generally categorized into wildfires and prescribed fires. On one hand, wildfires are unplanned wildland fires that occur either naturally or due to accidental or malicious human ignition. On the other hand, prescribed fires are wildland fires that are ignited intentionally to rejuvenate...

With wildfires becoming more frequent and severe in fire-prone regions affected by warmer and drier climate conditions, reducing hazardous fuels is increasingly recognized as a preventative strategy for promoting sustainability and safeguarding valued resources. Prescribed fire is one of the most cost-effective methods for reducing hazardous fuels and hence wildfire severity, yet empirical research on its effectiveness at minimizing damage to highly valued resources and assets (HVRAs) remains limited. The overarching objective of this study was to evaluate wildfire severity under differing...