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Evaluating Shuttle radar and interpolated DEMs for slope gradient and soil erosion estimation in low relief terrain

Journal Articles & Books
Diciembre, 2013
Australia

The error in slope gradient estimates provided by digital elevation models propagates to spatial modelling of erosion and other environmental attributes, potentially impacting land management priorities. This study compared the slope estimates of Shuttle Radar Topographic Mission (SRTM) DEMs with those generated by interpolation of topographic contours, at two grid cell resolutions. The magnitude and spatial patterns of error in DEM slope, and derived erosion estimates using the Revised Universal Soil Loss Equation (RUSLE), were evaluated at three sites in eastern Australia.

Nitrate transport modeling to evaluate source water protection scenarios for a municipal well in an agricultural area

Journal Articles & Books
Diciembre, 2011
Canadá

Fertilizers that are spread on agricultural fields can leach into aquifers and contaminate groundwater sources for drinking water particularly with nitrate. Modeling this phenomenon can help in evaluating the impact of current or future agricultural practices on nitrate content within an aquifer. The three-dimensional Water flow and Nitrate transport Global Model (WNGM), that was previously developed and applied to a well-capture zone, is actually used to simulate future land management scenarios over the same zone.

Crofting and bumblebee conservation: The impact of land management practices on bumblebee populations in northwest Scotland

Journal Articles & Books
Diciembre, 2010

The northwest of Scotland is a stronghold for two of the UK's rarest bumblebee species, Bombus distinguendus and Bombus muscorum. The predominant form of agricultural land management in this region is crofting, a system specific to Scotland in which small agricultural units (crofts) operate rotational cropping and grazing regimes. Crofting is considered to be beneficial to a wide range of flora and fauna. However, currently there is a lack of quantitative evidence to support this view with regard to bumblebee populations.

Using Detection Dogs and Rspf Models to Assess Habitat Suitability for Bears in Greater Yellowstone

Journal Articles & Books
Diciembre, 2015

In the northern U.S. Rockies, including the Greater Yellowstone Ecosystem (GYE), connectivity is a concern because large carnivores have difficulties dispersing successfully between protected areas. One area of high conservation value because of its importance for connecting the GYE to wilderness areas of central Idaho is the Centennial Mountains and surrounding valleys (2500 km²) along the Idaho—Montana border just west of Yellowstone National Park.

Vegetation Responses to Pinyon–Juniper Treatments in Eastern Nevada

Journal Articles & Books
Diciembre, 2014

Comparisons of tree-removal treatments to reduce the cover of single-leaf pinyon (Pinus monophylla Torr. and Frém.) and Utah juniper (Juniperus osteosperma [Torr.] Little), and subsequently increase native herbaceous cover in black sagebrush (Artemisia nova A. Nelson), are needed to identify most cost-effective methods. Two adjacent vegetation management experiments were initiated in 2006 and monitored until 2010 in eastern Nevada to compare the costs and efficacy of various tree reduction methods.

Grazing impacts on the susceptibility of rangelands to wind erosion: The effects of stocking rate, stocking strategy and land condition

Journal Articles & Books
Diciembre, 2015
Australia

An estimated 110 Mt of dust is eroded by wind from the Australian land surface each year, most of which originates from the arid and semi-arid rangelands. Livestock production is thought to increase the susceptibility of the rangelands to wind erosion by reducing vegetation cover and modifying surface soil stability. However, research is yet to quantify the impacts of grazing land management on the erodibility of the Australian rangelands, or determine how these impacts vary among land types and over time.

Internal Validation of Predictive Logistic Regression Models for Decision-Making in Wildlife Management

Journal Articles & Books
Diciembre, 2009

Predictive logistic regression models are commonly used to make informed decisions related to wildlife management and conservation, such as predicting favourable wildlife habitat for land conservation objectives and predicting vital rates for use in population models. Frequently, models are developed for use in the same population from which sample data were obtained, and thus, they are intended for internal use within the same population. Before predictions from logistic regression models are used to make management decisions, predictive ability should be validated.

Effects of land management on CO₂ flux and soil C stock in two Tanzanian croplands with contrasting soil texture

Journal Articles & Books
Diciembre, 2012
Tanzania
África

Evaluation of carbon dynamics is of great concern worldwide in terms of climate change and soil fertility. However, the annual CO₂ flux and the effect of land management on the carbon budget are poorly understood in Sub-Saharan Africa, owing to the relative dearth of data for in situ CO₂ fluxes. Here, we evaluated seasonal variations in CO₂ efflux rate with hourly climate data in two dry tropical croplands in Tanzania at two sites with contrasting soil textures, viz. clayey or sandy, over four consecutive crop-cultivation periods of 40 months.

Assessing gender roles in a changing landscape: diversified agro-pastoralism in drylands of West Pokot, Kenya

Journal Articles & Books
Diciembre, 2015
Kenya

Previous studies in drylands have shown that while gender roles are becoming more flexible, privatization and formalization of land tenure tends to marginalize women in drylands while environmental degradation leads to differential changes in gender workload. Chepareria, a ward in West Pokot County, has undergone the above-mentioned tenure and environmental changes and is nowadays dominated by private enclosures as a land management approach.

Perceptions of and Adaptation to Environmental Change in Forest-Adjacent Communities in Three African Nations

Journal Articles & Books
Diciembre, 2015
Rwanda
Guinea Ecuatorial
Camerún

SUMMARYSemi-structured interviews were used to explore how rural communities near forests are responding to environmental change in three African nations — Cameroon, Equatorial Guinea and Rwanda. The study first recounts people's perception of environmental change — what are the issues of greatest concern identified by local communities? Second, it explores people's responses to identified environmental problems and in particular the role of forests in these processes.