Passar para o conteúdo principal

page search

Displaying 1321 - 1332 of 2002

satellite-based green index as a proxy for vegetation cover quality in a Mediterranean region

Journal Articles & Books
Dezembro, 2012
Grécia

To preserve land quality and mitigating land degradation represent an important task for regional planning and environmental management of the Mediterranean region. Since land cover dynamics directly affect the landscape characteristics, remote sensing represents an effective tool for land quality assessment at large scale.

Land degradation during the Bronze Age in Hexi Corridor (Gansu, China)

Journal Articles & Books
Dezembro, 2012
China

Pollen and charcoal analysis, with high resolution AMS ¹⁴C dating, on two sediment sections in the Hexi Corridor track the process of settlement development and abandonment during the Bronze Age. The evidence shows that agricultural activity during the Bronze Age caused an increase in farmland and a decrease in the abundance of Artemisia grassland in the Hexi Corridor. Land degradation is probably the main cause for decreased agricultural activity and settlement abandonment. Agriculture- induced soil fertility loss and land salinization contributed to the process of land degradation.

spatial nexus between population growth and land degradation in a dry Mediterranean region: a rapidly changing pattern?

Journal Articles & Books
Dezembro, 2012
Itália
Europa

A better understanding of the spatial linkage between the distribution of land vulnerable to degradation and long-term population growth may contribute to sustainable land management of dry regions. Such a nexus has received increasing attention among politicians and local stakeholders, as its complex outcomes depend on mutual interactions between socioeconomic and biophysical factors. This is particularly true in southern Europe, where important processes of land degradation (LD) have been observed in recent years.

Accounting for space and time in soil carbon dynamics in timbered rangelands

Journal Articles & Books
Dezembro, 2012

Employing rangelands for climate change mitigation is hindered by conflicting reports on the direction and magnitude of change in soil organic carbon (ΔSOC) following changes in woody cover. Publications on woody thickening and deforestation, which had led to uncertainty in ΔSOC, were re-evaluated, and the dimensional-dependence of their data was determined. To model the fundamentals of SOC flux, linked SOC pools were simulated with first-order kinetics. Influences from forest development timelines and location of mature trees, with a potential for deep-set roots, were considered.

Dynamics of aggregate destabilization by water in soils under long-term conservation tillage in semiarid Spain

Journal Articles & Books
Dezembro, 2012
Espanha

Due to particular soil and climate conditions and inappropriate agricultural practices, Aragon (NE Spain) is a region prone to land degradation by water erosion. For this reason, the adoption of conservation tillage systems has been encouraged as an alternative to preserve soil and water in this region. However, little information concerning soils on which these techniques are applied is available.

Challenges and Opportunities for Transboundary Water Cooperation in Central Asia: Findings from UNECE's Regional Assessment and Project Work

Journal Articles & Books
Dezembro, 2012
Ásia Central

This paper provides an overview of topical issues and problems related to transboundary water resources in Central Asia and their management in the light of the Second Assessment carried out under the UNECE Water Convention (2009– 2011) as well as experiences from ongoing projects.

free and open source programming library for landscape metrics calculations

Journal Articles & Books
Dezembro, 2012

Landscape metrics are used in a wide range of environmental studies such as land use change and land degradation studies, soil erosion and run-off predictions, management of hunting communities, and strategic planning for environmental management, to name just a few. Due to their utility for a variety of applications, there are many indices and software packages that have been designed to provide calculations and analysis of landscape structure patterns in categorical maps.

Evaluation of runoff, peak flow and sediment yield for events simulated by the AnnAGNPS model in a Belgian agricultural watershed

Journal Articles & Books
Dezembro, 2012
Bélgica

The AnnAGNPS model, widely utilized as a practical tool for addressing erosion problems and land use planning, was implemented in a small agricultural watershed located in central Belgium, to assess its prediction capacity of runoff, peak flow and sediment yield in humid temperate conditions. Model performance was evaluated at the event scale by using a database reporting hydrological, geomorphologic and land use data collected during a 2-year period. Seventeen events were modelled and compared with the corresponding observations at the watershed outlet.

Mitigating land degradation caused by wildfire: Application of the PESERA model to fire-affected sites in central Portugal

Journal Articles & Books
Dezembro, 2012
Portugal

Wildfires represent an important agent of land degradation in temperate sub-humid ecosystems, including southern European Mediterranean countries. Identification of integrated conservation approaches that can reduce or prevent degradational impacts is the aim of the EU-funded DESIRE research program, part of which is concerned with quantifying the likely benefit of acceptable alternative conservation strategies to wildfire.

Landowner response to policies regulating land improvements in Finland: Lease or search for other options?

Journal Articles & Books
Dezembro, 2012
Finlândia

Land improvements with long pay-back periods are often delayed on leased agricultural land. The delay in improvements has been found to result in land degradation, decreased land productivity and environmental problems. An important question is thus how landowners would respond to regulations and mandates concerning land improvements. Based on a Finnish landowner survey, we analysed landowner choices under certain land improvement regulations, using the currently dominant choice of leasing land for agricultural use as the benchmark.

Integrated Approach to Crop Genetic ImprovementF

Journal Articles & Books
Dezembro, 2012

[Formula: see text] [ Martin A. J. Parry ] The balance between the supply and demand of the major food crops is fragile, fueling concerns for long‐term global food security. The rising population, increasing wealth and a proliferation of non‐food uses (e.g. bioenergy) has led to growing demands on agriculture, while increased production is limited by greater urbanization, and the degradation of land. Furthermore, global climate change with increasing temperatures and lower, more erratic rainfall is projected to decrease agricultural yields.