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Supporting conservation with biodiversity research in sub-Saharan Africa’s human-modified landscapes
Protected areas (PAs) cover 12� % of terrestrial sub-Saharan Africa. However, given the inherent inadequacies of these PAs to cater for all species in conjunction with the effects of climate change and human pressures on PAs, the future of biodiversity depends heavily on the 88� % of land that is unprotected. The study of biodiversity patterns and the processes that maintain them in human-modified landscapes can provide a valuable evidence base to support science-based policy-making that seeks to make land outside of PAs as amenable as possible for biodiversity persistence.
Distribution and interaction of white-tailed deer and cattle in a semi-arid grazing system
In order to optimize production, range managers need to understand and manage the spatial distribution of free-ranging herbivores, although this task becomes increasingly difficult as ranching operations diversify to include management of wildlife for recreational hunting. White-tailed deer are sympatric with cattle throughout much of their range and are a valuable commodity in southern rangelands. The spatial distribution of deer and cattle was monitored over 1 year during four trials each lasting 12 days.
Spatial assessment of soil erosion risk using RUSLE and GIS techniques
Soil erosion by water is considered a major cause for land degradation in Jordan, where 0.14 cm of productive top soil is eroded annually. This investigation is intended to estimate the annual soil loss in Wadi Kerak watershed, and to examine the spatial patterns of soil loss and intensity, as an essential procedure for proper planning of conservation measures. To achieve these objectives, the revised universal soil loss equation (RUSLE) model has been applied in a geographical information system framework.
Modeling vegetation heights from high resolution stereo aerial photography: An application for broad-scale rangeland monitoring
Vertical vegetation structure in rangeland ecosystems can be a valuable indicator for monitoring rangeland health or progress toward management objectives because of its importance for assessing riparian areas, post-fire recovery, wind erosion, and wildlife habitat. Federal land management agencies are directed to monitor and manage rangelands at landscapes scales, but traditional field methods for measuring vegetation heights are often too costly and time consuming to apply at these broad scales.
Precision, Repeatability, and Efficiency of Two Canopy-Cover Estimate Methods in Northern Great Plains Vegetation
Government agencies are subject to increasing public scrutiny of land management practices. Consequently, rigorous, yet efficient, monitoring protocols are needed to provide defensible quantitative data on the status and trends of rangeland vegetation. Rigor requires precise, repeatable measures, whereas efficiency requires the greatest possible information content for the amount of resources spent acquiring the information. We compared two methods--point frequency and visual estimate--of measuring canopy cover of individual plant species and groups of species (forbs vs.
Mapping and Monitoring Cheatgrass Dieoff in Rangelands of the Northern Great Basin, USA ☆,☆☆,★
Understanding cheatgrass (Bromus tectorum) dynamics in the Northern Great Basin rangelands, USA, is necessary to effectively manage the region's lands. This study's goal was to map and monitor cheatgrass performance to identify where and when cheatgrass dieoff occurred in the Northern Great Basin and to discover how this phenomenon was affected by climatic, topographic, and edaphic variables. We also examined how fire affected cheatgrass performance.
Restoration approaches used for degraded peatlands in Ruoergai (Zoige), Tibetan Plateau, China, for sustainable land management
Sedge dominated peatlands do not rehabilitate well after being drained for rangelands and specific approaches are required in order to restore these sites. Restoration by blocking drainage canals aims to recover peatland functions, principally by raising the water table. Field surveys in Ruoergai, China identified the status of peatland degradation and satellite image analysis concluded that most of Ruoergai's peatlands are degraded mainly due to drainage and overgrazing.
Using Social Media to Discover Public Values, Interests, and Perceptions about Cattle Grazing on Park Lands
In the western United States, livestock grazing often co-exists with recreation, cultural resource management and biodiversity protection on federal and state protected rangelands as well as on many local government open space areas. While the value of livestock grazing for managing rangeland vegetation to reduce fire fuel loads and improve wildlife habitat is increasingly recognized by resource management professionals, public concerns, and conflict between recreationist and livestock have led to reductions in public land grazing.
influence of land use on desertification processes
Site degradation occurs mainly through deterioration of the soil's capacity to capture and store water, as well as the loss of organic matter or the accumulation of salts or other toxic substances in the soil. This degradation process, leading to the reduction of the biotic potential of the site, is known as desertification. In this study, changes in bulk density, organic matter, and electrical conductivity are used as indicators of desertification in northeast Mexico.
Hierarchical object-based classification of ultra-high-resolution digital mapping camera (DMC) imagery for rangeland mapping and assessment
Ultra-high-resolution digital aerial imagery has great potential to complement or replace ground measurements of vegetation cover for rangeland monitoring and assessment. This research investigated object-based image analysis (OBIA) techniques for classifying vegetation in southwestern USA arid rangelands with 4 cm resolution digital aerial imagery. We obtained high r-square values for the regressions relating ground- to image-based measures of percent cover (r-square values: 0.82–0.92).
Hardwood Rangeland Landowners in California from 1985 to 2004: Production, Ecosystem Services, and Permanence
A longitudinal study of California hardwood rangelands shows significant change in landowner characteristics and goals. Results of three studies spanning 1985 to 2004 were used to develop and evaluate a multiagency research and extension program known as the Integrated Hardwood Range Management Program. Program-sponsored education and research aimed at encouraging landowners to change woodland management has been reflected in a significant reduction in oak cutting and an increase in oak planting.