Treesearch

Population size and density estimates have traditionally been acceptable ways to track species’ response to changing environments; however, species' population centroid elevation has recently been an equally important metric. Packera franciscana (Greene) W.A. Weber and A. Love (Asteraceae; San Francisco Peaks ragwort) is a single mountain endemic plant found only in upper treeline and alpine talus habitats of the San Francisco Peaks in northern Arizona and is listed by the U.S. Fish and Wildlife Service as a Threatened species under the Endangered Species Act. We used 2 recreational...

Wildfires have been increasing in size and severity over recent decades. Forest managers use fuel treatments, including tree thinning and prescribed burning, to reduce the risk of high-severity fire. The impact of fuel treatments on carbon dynamics is not fully understood; previous research indicates that because carbon is removed during fuel treatments, the net effect may not be a reduction of carbon lost in the case of wildfire. The Rodeo-Chediski Fire, which burned in Arizona in 2002, was one of the largest and most severe wildfires recorded in the southwestern United States. Our...

A synthesis for fire managers summarizes and interprets a body of information, presents its meaning in an objective, unbiased way, and describes its implications for decisionmakers. Following are suggestions for ways to strengthen syntheses on fire and on other natural resource issues: Include managers, scientists, and science delivery specialists in planning, developing, and delivering syntheses. If a synthesis has unique regional components, include someone from each region in the planning team and consider these needs in writing and packaging. Use managers as authors, co-authors, or...

Hydrogeomorphic processes operating at watershed, process zone and site scales influence the distribution of riparian vegetation. However, most studies examining the relationships between hydrogeomorphic processes and riparian vegetation are conducted at site scales. We quantified the relative importance of watershed, process zone and site geomorphic characteristics for predicting riparian plant community types and plant species abundances in four small mountain watersheds in central Nevada, USA.

Main results and important changes in China’s NFI are documented, both to support continued trend analysis and to provide data users with historical perspective. New technologies and data needs ensure that the Chinese NFI, like the national inventories in other countries, will continue to evolve. Within the context of historical change and current conditions, likely directions for this evolution are suggested.

Particulate organic matter (POM) processing is an important driver of aquatic ecosystem productivity that is sensitive to nutrient enrichment and drives ecosystem carbon (C) loss. Although studies of single concentrations of nitrogen (N) or phosphorus (P) have shown effects at relatively low concentrations, responses of litter breakdown rates along gradients of low-to-moderate N and P concentrations are needed to establish likely interdependent effects of dual N and P enrichment on baseline activity in stream ecosystems. We established 25 combinations of dissolved inorganic N (DIN; 55-545...

Across the western US, the two most prevalent native forest insect pests are mountain pine beetle (MPB; Dendroctonus ponderosae; a bark beetle) and western spruce budworm (WSB; Choristoneura freemani; a defoliator). MPB outbreaks have received more forest management attention than WSB outbreaks, but studies to date have not compared their cumulative mortality impacts in an integrated, regional framework. The objectives of this study are to: (1) map tree mortality associated with MPB and WSB outbreaks by integrating forest health aerial detection surveys (ADS; 1970–2012), Landsat time...

Actualmente el comercio mundial se realiza a gran escala, estableciéndose requisitos cada día más exigentes, donde los productores y consumidores requieren realizar transacciones comerciales con unamayor de confiabilidad, y donde la calidad de los productos y servicioses un aspecto crítico en las actividades comerciales.

Actualmente, debido a la globalización, las relaciones comerciales crecen rápidamente, las cuales son más exigentes día a día; dicho desafío requiere que las organizaciones mejoren sus procesos y productos permitiendo realizar transacciones con un alto grado de confiabilidad, con el debido respaldo de la calidad de los productos y/o servicios que se comercializan.

Phosphorus (P) is an essential fertilizer for agricultural production but is also a potent aquatic pollutant. Current P management fails to adequately address both the issue of food security due to P scarcity and P pollution threats to water bodies. As centers of food consumption and waste production, cities transport and store much P and thus provide important opportunities to improve P management. Substance flow analysis (SFA) is often used to understand urban P cycling and to identify inefficiencies that may be improved on. However, SFAs typically do not examine the factors that drive...