Land use change in rangeland ecosystems is pervasive throughout the western United States with widespread ecological, social and economic implications. In California, rangeland habitats have high biodiversity value, provide significant habitat connectivity and form the foundation for a number of ecosystem services. To comprehensively assess the conservation status of these habitats, we analyzed...

G ecosystems cover 30% to 40% of the earth’s terrestrial surface, provide critical habitat for large numbers of species, and support extensive grazing economies on every continent except Antarctica (Coupland 1979, Samson and Knopf 1996). In the United States alone, there are approximately 312 million hectares of rangeland (NRC 1994). Fire, grazing, and climate combine to act as the primary ecos...

We present an ecological framework for considering ecosystem degradation and restoration, particularly in rangelands and arid environments. The framework is a synthesis of three conceptual models previously developed by several rangeland and restoration ecologists. We focus first on distinctions and connections between structural and functional components of rangeland ecosystems and then on dis...

We summarize available information about the relationships between oak overstory and understory plants for major California rangeland types. Understory biomass, productivity, and plant species composition vary considerably because of geographic location, overstory species composition, and overstory density and distribution. Deciduous oak canopies in areas with less than 50 cm annual precipitati...

Chemical control ofweeds has increased agricultural productivity, but complete reliance on chemicals has serious drawbacks. These include high cost per acre, decreasing effectiveness, negative effects on plant community diversity, and increased opportunities for environmental contamination. One alternative is biocontrol, the use ofbiologicalfactors that naturally limit weed populations. Long-te...

This article reports a rapid method for rangeland assessments in Kenya, Ethiopia and Uganda by harnessing pastoralists’ indigenous knowledge among the Orma, Afar and Karamojong pastoralists. The study developed and evaluated a methodological framework for conducting joint assessments with pastoralist range scouts. The framework has four components: selection of ecological and anthropogenic indi...

Livestock grazing affects over 60% of the world's agricultural lands and can influence rangeland ecosystem services and the quantity and quality of wildlife habitat, resulting in changes in biodiversity. Concomitantly, livestock grazing has the potential to be detrimental to some wildlife species while benefiting other rangeland organisms. Many imperiled grouse species require rangeland landsca...

We tested the accuracy of an atmospheric correction method that depends on clear water bodies to infer solar and atmospheric parameters for radiative transfer equations by measuring the reflectance signature of four prominent south Texas rangeland plants with the Earth Resource Technology (LANDSAT) satellite multispectral scanner (MSS) and a ground-based Exotech Model 20 spectroradiometer. The ...