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Desertification and livestock grazing: The roles of sedentarization, mobility and rest

Journal Articles & Books
Dezembro, 2011

Pastoralism is an ancient form of self-provisioning that is still in wide use today throughout the world. While many pastoral regions are the focus of current desertification studies, the long history of sustainability evidenced by these cultures is of great interest. Numerous studies suggesting a general trend of desertification intimate degradation is a recent phenomenon principally attributable to changes in land tenure, management, and treatment.

Analyzing wildfire exposure and source–sink relationships on a fire prone forest landscape

Journal Articles & Books
Dezembro, 2012
Estados Unidos

We used simulation modeling to analyze wildfire exposure to social and ecological values on a 0.6millionha national forest in central Oregon, USA. We simulated 50,000 wildfires that replicated recent fire events in the area and generated detailed maps of burn probability (BP) and fire intensity distributions. We also recorded the ignition locations and size of each simulated fire and used these outputs to construct a fire source–sink ratio as the ratio of fire size to burn probability.

Demography beyond the population

Journal Articles & Books
Dezembro, 2016

Population ecology, the discipline that studies the dynamics of species’ populations and how they interact with the environment, has been one of the most prolific fields of ecology and evolution. Demographic research is central to quantifying population‐level processes and their underlying mechanisms and has provided critical contributions to a diversity of research fields. Examples include the spread of infectious diseases, eco‐evolutionary dynamics and rapid evolution, mechanisms underlying invasions and extinctions, and forest productivity.

Assessing the impacts of watershed indexes and precipitation on spatial in-stream E. coli concentrations

Journal Articles & Books
Dezembro, 2012
Estados Unidos

Pathogen contamination of waterbodies, which is often identified by the presence of pathogen indicators such as Escherichia coli, is a major water quality concern in the United States. Reducing in-stream pathogen contamination requires an understanding of the combined impacts of land cover, climatic conditions, and anthropogenic activities at the watershed scale. In this study these factors are considered by assessing linear relationships between in-stream E. coli water quality data, watershed indexes, and rainfall for the Squaw Creek Watershed, IA, USA.

Response of Two Sagebrush Sites to Low-Disturbance, Mechanical Removal of Piñyon and Juniper

Journal Articles & Books
Dezembro, 2010
Estados Unidos

In the Great Basin of the western United States, expansion of Pinus monophylla (singleleaf piñyon) and Juniperus osteosperma (Utah juniper) out of historic woodlands and into Artemisia spp. (sagebrush) shrubland communities can facilitate the invasion of exotic downy brome (Bromus tectorum) and lead to decreases in ecological and economic values of shrublands. This expansion has, therefore, been the focus of management efforts, including the thinning or removal of trees in areas that were historically shrubland.

Participatory Criteria Selection: Finding Conflictive Positions in Environmental Postassessment of Land Management and Restoration Actions

Journal Articles & Books
Dezembro, 2016

Stakeholder participation in environmental assessment of past land management and restoration actions in drylands is important to improve knowledge and management of these ecosystems. Participatory identification and prioritization of monitoring and assessment criteria, while increasingly incorporated into assessment, is still perceived as challenging due to conflicting values and perspectives among stakeholders.

Effects of grazing exclusion on the spatial variability of subalpine plant communities: A multiscale approach

Journal Articles & Books
Dezembro, 2011

The fine-scale spatial structure of plant communities is a key component for understanding the dynamics in vegetation following changes in land management but needs to be assessed at an appropriate scale. We studied the response of plant diversity and spatial variability of species and trait composition to grazing vs. non-grazing (>20 years) using different grain sizes of sampling in three subalpine plant communities.