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Mapping Ecological Processes and Ecosystem Services for Prioritizing Restoration Efforts in a Semi-arid Mediterranean River Basin

Journal Articles & Books
Décembre, 2014
Espagne

Semi-arid Mediterranean regions are highly susceptible to desertification processes which can reduce the benefits that people obtain from healthy ecosystems and thus threaten human wellbeing. The European Union Biodiversity Strategy to 2020 recognizes the need to incorporate ecosystem services into land-use management, conservation, and restoration actions. The inclusion of ecosystem services into restoration actions and plans is an emerging area of research, and there are few documented approaches and guidelines on how to undertake such an exercise.

Communicative Action to Level the Playing Field in Forest Plantations in Indonesia

Journal Articles & Books
Décembre, 2014
Indonésie

The government of Indonesia allocated state land to private companies to establish forest plantations. However, ownership of this land was contested by some Sumatran communities. The plantation company, endorsed by the government, quickly developed a partnership to resolve the conflict, but this was unclear and inequitable. Action research was carried out to facilitate communication among stakeholders. This communicative action changed some perceptions and shared values began to emerge. A forum was established, which contributed to equitability producing a better partnership.

FUZZY RULE BASE APPROACH FOR DEVELOPING A SOIL PROTECTION INDEX MAP: A CASE STUDY in the UPPER AWASH BASIN, ETHIOPIAN HIGHLANDS

Journal Articles & Books
Décembre, 2014
Éthiopie
Italie

Land use practices and vegetation cover distribution are considered to be the most important dynamic factors that influence the land degradation or the soil erosion of a region. In this study, a Soil Protection Index (SPI) is defined as a function of land use practices and intensity of vegetation cover. This index is used to map the relative degree of protection of topsoil from being eroded by external effects such as rainfall and overland flow. A fuzzy rule‐based model integrated within ArcGIS® has been set‐up and tested with the aim to develop SPI maps.

Forecasts of habitat suitability improve habitat corridor efficacy in rapidly changing environments

Journal Articles & Books
Décembre, 2014

AIM: Habitat fragmentation threatens species’ persistence by increasing subpopulation isolation and vulnerability to stochastic events, and its impacts are expected to worsen under climate change. By reconnecting isolated fragments, habitat corridors should dampen the synergistic impacts of habitat and climate change on population viability. Choosing which fragments to reconnect is typically informed by past and current environmental conditions. However, habitat and climate are dynamic and change over time.

Ecological correlates of local extinction and colonisation in the British ladybird beetles (Coleoptera: Coccinellidae)

Journal Articles & Books
Décembre, 2014

Five main drivers of population declines have been identified: climate change, habitat degradation, invasive alien species (IAS), overexploitation and pollution. Each of these drivers interacts with the others, and also with the intrinsic traits of individual species, to determine species’ distribution and range dynamics.

Potential Impacts and Management Implications of Climate Change on Tampa Bay Estuary Critical Coastal Habitats

Journal Articles & Books
Décembre, 2014

The Tampa Bay estuary is a unique and valued ecosystem that currently thrives between subtropical and temperate climates along Florida’s west-central coast. The watershed is considered urbanized (42� % lands developed); however, a suite of critical coastal habitats still persists. Current management efforts are focused toward restoring the historic balance of these habitat types to a benchmark 1950s period. We have modeled the anticipated changes to a suite of habitats within the Tampa Bay estuary using the sea level affecting marshes model under various sea level rise (SLR) scenarios.

LAND RESOURCES OF THE MEDITERRANEAN: STATUS, PRESSURES, TRENDS AND IMPACTS ON FUTURE REGIONAL DEVELOPMENT

Journal Articles & Books
Décembre, 2014
Algérie
Libye
Égypte
Asie occidentale
Afrique septentrionale

The Mediterranean region covers about 854 million ha, but only 118 million (or 14 per cent) are suitable for agricultural production. In North Africa and the Middle East (MENA), agricultural land covers about 5 per cent; in Egypt and Algeria, it occupies less than 4 per cent and, in Libya, less than 2 per cent of the total national land area. Across the Mediterranean region land use divides between natural pastures/rangelands (ca. 15 per cent), forests and woodlands (ca. 8 per cent), with the ca.

Nitrogen isotope tracer acquisition in low and tall birch tundra plant communities: a 2� year test of the snow–shrub hypothesis

Journal Articles & Books
Décembre, 2014

Deciduous shrub density and landcover are increasing across many areas of the Arctic. Shrub growth may be promoted by a snow–shrub feedback whereby relatively tall shrubs accumulate deeper snow, raising winter soil temperature minima, increasing microbial activity, and enhancing soil solution nitrogen (N). Although there is good evidence for the above components of the hypothesis, it has not yet been determined if shrubs can access the elevated N pool generated by deepened snow.

Natural Regeneration Processes in Big Sagebrush (Artemisia tridentata)

Journal Articles & Books
Décembre, 2014

Big sagebrush, Artemisia tridentata Nuttall (Asteraceae), is the dominant plant species of large portions of semiarid western North America. However, much of historical big sagebrush vegetation has been removed or modified. Thus, regeneration is recognized as an important component for land management. Limited knowledge about key regeneration processes, however, represents an obstacle to identifying successful management practices and to gaining greater insight into the consequences of increasing disturbance frequency and global change.

causes, effects and challenges of Sahelian droughts: a critical review

Journal Articles & Books
Décembre, 2014

This paper is a critical synthesis of the causes, effects and challenges of the Sahelian droughts. The results show that the four main causes of the Sahelian droughts are as follows: sea surface temperature changes, vegetation and land degradation, dust feedbacks and human-induced climate change. However, human-induced climate change is seen as the major drought-determining factor because it controls sea surface temperatures, dust feedbacks and vegetation degradation.

Implications of carbon forestry for local livelihoods and leakage

Journal Articles & Books
Décembre, 2014
Mexique

• CONTEXT : An inequitable distribution of the costs and benefits of carbon forestry could undermine its role in tackling climate change, but safeguarding local livelihoods could undercut its effectiveness. • AIMS : We simulate a reforestation program in a densely populated locality in central Mexico to analyze indirect land-use change, or leakage, associated with the program and its implications for local livelihoods. • METHODS : An agent-based, general equilibrium model simulates scenarios that deconstruct the sources of leakage and livelihood outcomes.

Stakeholders’ Responses to the Use of Innovative Water Trading Systems in East Anglia, England

Journal Articles & Books
Décembre, 2014

It is widely recognised that the current abstraction licensing system in England needs to be reformed to meet the challenges of future environmental flow requirements, likely increases in water demands and climate change. The UK Government has committed to the reform of the abstraction regime in England and work is underway, including the Welsh Government, to assess the impacts of different reform options, working closely with stakeholders.