Treesearch

The advent of computerized mapping has greatly expanded the ability of land managers to map many aspects of ecological systems, such as tree species, soil types, wildlife habitat, air quality, and water conditions. Mapping the social and cultural aspects of ecological systems, however, has proved much more challenging. This atlas uses the Olympic Peninsula in western Washington to illustrate how the application of computerized mapping to the study of human ecology can help address this challenge. Human ecology is a science that takes a systems approach to understanding humanenvironmental...

Global Positioning System (GPS) units used in animal telemetry often suffer from nonrandom data loss and location error. GPS units use stored satellite information to estimate locations, including almanac and ephemeris data reflecting satellite positions at weekly and at <4-hr temporal scales, respectively. Using the smallest GPS collars (45–51 g) available for mammals, we evaluate how satellite information and environmental conditions affected GPS performance in 27 mobile trials, and field reliability during 56 deployments on Pacific marten (Martes caurina).

Carnivore guilds play a vital role in ecological communities by cascading trophic effects, energy and nutrient transfer, and stabilizing or destabilizing food webs. Consequently, the structure of carnivore guilds can be critical to ecosystem patterns. Body size is a crucial influence on intraguild interactions, because it affects access to prey resources, effectiveness in scramble competition, and vulnerability to intraguild predation. Coyotes (Canis latrans), bobcats (Lynx rufus), gray foxes (Urocyon cinereoargenteus), raccoons (Procyon lotor), red foxes (Vulpes vulpes), and striped...

Snowcover pattern and persistence have important implications for planetary energy balance, climate sensitivity to forcings, and vegetation structure, function, and composition. Variability in snow cover within mountainous regions of the Pacific Northwest, USA is attributable to a combination of anthropogenic climate change and climate oscillations. However, snowcovered areas can be heterogeneous and patchy, requiring more detailed mapping of snow trends to understand their potential influences on montane forests. We used standard dailyMODIS snow products (MOD10A1.5) to investigate the...

Important goals for studying dam removal are to learn how rivers respond to large and rapid introductions of sediment, and to develop predictive models to guide future dam removals. Achieving these goals requires organizing case histories systematically so that underlying physical mechanisms determining rates and styles of sediment erosion, transport, and deposition are revealed. We examine a range of dam removals predominantly in the western US over the last decade, and extract useful lessons and trends that can be used to predict the response of rivers to future removals.

This report provides a statistical analysis of the data collected from two survey regions of the United States, the Pacific Northwest and the Southeast. The survey asked about individual agricultural landowners’ characteristics, characteristics of their land, and the landowners’ willingness to enroll in a tree planting program under incentive payments for carbon sequestration. From this statistical analysis, we found both similar and contrasting features between the two survey regions. The Southeast is more responsive to incentive payment for carbon sequestration than the Pacific Northwest,...

Nine mid-latitude to high-latitude headwater catchments – part of the Northern Watershed Ecosystem Response to Climate Change (North-Watch) programme – were used to analyze threshold response to rainfall and snowmelt-driven events and link the different responses to the catchment characteristics of the nine sites. The North-Watch data include daily time-series of various lengths of multiple variables such as air temperature, precipitation and discharge. Rainfall and meltwater inputs were differentiated using a degree-day snowmelt approach. Distinct hydrological events were identified, and...

Forest disturbance and long-term succession towards old-growth are thought to increase nitrogen (N) availability and N loss, which should increase soil ä15N values. We examined soil and foliar patterns in N and ä15N, and soil N mineralization, across 800 years of forest succession in a topographically complex montane landscape influenced by human logging and wildfire. In contrast to expectations, we found that disturbance caused declines in surface mineral soil ä15N values, both in logged forests measured 40–50 years after disturbance, and in unlogged forests disturbed by severe wildfire...

Background: Nearly 40 years of research provides an extensive body of evidence about human health, well-being, and improved function benefits associated with experiences of nearby nature in cities. Objectives: We demonstrate the numerous opportunities for future research efforts that link metro nature, human health and well-being outcomes, and economic values. Methods: We reviewed the literature on urban nature-based health and well-being benefits. In this review, we provide a classification schematic and propose potential economic values associated with metro nature services. Discussion:...

Inter-annual variability (IAV) of forest Net Primary Productivity (NPP) is a function of both extrinsic (e.g., climate) and intrinsic (e.g., stand dynamics) drivers. As estimates of NPP in forests are scaled from trees to stands to the landscape, an understanding of the relative effects of these factors on spatial and temporal behavior of NPP is important. Although a high degree of spatial coherence (i.e., the degree of spatial synchrony over time) is often assumed, this inherent behavior is rarely examined. Quantifying this term may improve future predictions as site-level estimates are...