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Climate Change and Food Security in Sub-Saharan Africa: A Systematic Literature Review

Peer-reviewed publication
Décembre, 2009
Global

In recent years it has become clear that climate change is an inevitable process. In Sub-Saharan Africa, the expectation is that climate change will have an especially negative impact, not only a result of projected warming and rainfall deficits, but also because of the vulnerability of the population. The impact upon food security will be of great significance, and may be defined as being composed of three components: availability, access, and utilization.

Assessing the Impact of Land Use Policy on Urban-Rural Sustainability Using the FoPIA Approach in Yogyakarta, Indonesia

Peer-reviewed publication
Décembre, 2009
Indonesia

This paper presents the results of a sustainability impact assessment (SIA) of policy induced land use changes in Yogyakarta, Indonesia. The regional problems include rapid expansions of urban areas, due to high population pressure, and the conversion of paddy fields and forests into settlements. The objective of this study was to assess the impacts of two land use policies on social, economic, and environmental Land Use Functions (LUFs) in Yogyakarta.

Differences in Net Primary Productivity Among Contrasting Habitats in Artemisia ordosica Rangeland of Northern China

Journal Articles & Books
Décembre, 2009
Chine

Artemisia ordosica Krasch. is a semishrub native to the Ordos Plateau of Inner Mongolia, northern China, and forms a unique and dominant vegetation type in the sandland of the region. To determine the variation of productivity in A. ordosica rangeland, we investigated net primary production (NPP), fine root turnover, soil microbial C (Cmic), and soil organic carbon density (SOCd) on sand dunes differing in mobility (i.e., fixed, semifixed, and shifting sand dunes) in Mu Us sandland.

Enabling the uptake of livestock-water productivity interventions in the crop-livestock systems of sub-Saharan Africa

Journal Articles & Books
Décembre, 2009
Afrique

Livestock-water productivity (LWP) refers to a set of innovations that could contribute towards reducing the amount of water needed per unit of output generated. But what does it take to get these ideas adopted by livestock keepers in crop-livestock systems? In this paper, we treat LWP as an innovation, and consider in what ways it may be introduced and/or developed among the crop-livestock agricultural systems by drawing on successful examples of change.

Impacts of silica-based defences in grasses on the feeding preferences of sheep

Journal Articles & Books
Décembre, 2009

Grasses, which dominate many terrestrial ecosystems, sustain high densities of grazing mammals, so are of great economic and ecological importance. Traditionally, grasses are thought to be adapted to tolerate grazing rather than defend against it; however, silica deposited in the leaves of grasses has recently been shown to act as a feeding deterrent to invertebrate herbivores and small mammals. This study assesses whether silica is effective as a feeding deterrent to larger mammalian herbivores.

Practical Challenges in Private Stewardship of Rangeland Ecosystems: Yellow Starthistle Control in Sierra Nevadan Foothills

Journal Articles & Books
Décembre, 2009

Private landowners are often de facto stewards of biodiversity and ecosystem services. In California's Sierra Nevada foothills, ranchers frequently present the only defense against biological invasions in private rangelands. Although ranchers' land management goals (e.g., the desire to control invasive species) can be consistent with ecosystem protection, practical constraints often limit their success. Considerable research on the invasive weed, yellow starthistle (Centaurea solstitialis L.), has produced numerous control strategies.

Effects of crop abandonment and grazing exclusion on available soil water and other soil properties in a semi-arid Mongolian grassland

Journal Articles & Books
Décembre, 2009

Improper cropping and overgrazing have led to land degradation in semi-arid regions, resulting in desertification. During desertification, vegetation changes have been widely observed, and are likely controlled to some extent by soil water. The purpose of this study was to investigate changes in soil physical properties, organic C, and vegetation induced by land-use changes, with special reference to the dynamics of available soil water.

Land use and disturbance effects on the dynamics of natural ecosystems of the Monte Desert: Implications for their management

Journal Articles & Books
Décembre, 2009

The complex interactions between human activity and natural processes determine non-linear dynamics in ecosystems that can difficult their management. Human settlements in arid lands contribute to the modification of disturbance regimes, including the introduction of new disturbances and the elimination of others. In consequence, they can alter the functional mechanisms that allow systems to overcome limiting factors, leading to desertification.

conservation auction for landscape linkage in the southern Desert Uplands, Queensland

Journal Articles & Books
Décembre, 2009

Conservation auctions are a type of market-based instrument (MBI) that can achieve a more cost-efficient allocation of public funds than approaches such as devolved grants. In this paper, the conduct of a multiple round conservation auction to improve biodiversity management in a rangelands area is outlined. The auction was designed to develop a wildlife corridor across the southern Desert Uplands bioregion in Queensland and to improve management of rangelands areas. The conservation auction incorporated two important new design features.

Trends in productivity of crops, fallow and rangelands in Southwest Niger: Impact of land use, management and variable rainfall

Journal Articles & Books
Décembre, 2009
Niger

To document trends in land use and herbaceous production, 71 field sites sampled among cropped fields, fallow fields and rangelands in the Fakara region (Niger) were monitored from 1994 to 2006. The overall trend in land use confirmed the historical increase of the cropped areas since mid 20th century, at an annual rate of 2% from 1994 to 2006. This trend is the result of changes in the relative extent of fields permanently cropped and fields under shifting cultivation, and for the latter, the relative proportion of short (3 years) and long (10 years) duration fallows.

Interacting effects of management and environmental variability at multiple scales on invasive species distributions

Journal Articles & Books
Décembre, 2009
Nouvelle-Zélande

1. The distribution and abundance of invasive species can be driven by both environmental variables and land management decisions. However, understanding these relationships can be complicated by interactions between management actions and environmental variability, and differences in scale among these variables. The resulting 'context-dependence' of management actions may be well-appreciated by ecologists and land managers, but can frustrate attempts to apply general management principles. 2.

Contingent Valuation of Woodland-Owner Private Amenities in Spain, Portugal, and California

Journal Articles & Books
Décembre, 2009
Portugal
Espagne

Most of the Mediterranean woodlands in Spain, Portugal, and California are managed as agrosilvopastoral enterprises, producing some combination of livestock, wood, cork products, and crops, as well as wildlife habitat and diverse environmental services. Private amenity benefits to landowners have been suggested as an explanation for high land prices and the persistence of such rangeland enterprises despite apparently marginal cash returns.