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Aquatic systems and water security in the Metropolitan Valley of Mexico City

Journal Articles & Books
december, 2011

In megacities water quantity and quality are threatened by complex and interrelated processes caused by population growth, land use change, unsustainable agricultural practices, deforestation, erosion, destruction of ecosystems, lack of planning, laissez-faire policies, unsustainable water management, political conflicts, and increasingly also by the impacts of climate change.

Numerical research of extreme wind-induced dust transport in a semi-arid human-impacted region of Mexico

Journal Articles & Books
december, 2011
Mexico

A numerical research is carried out to investigate the regional impact of extreme wind-induced dust transport in the central-northern part of Mexico. In boreal winter, strong wind soil erosion processes occur in the arid zones of the Mexican highlands, as a consequence of land use change and land cover change. The effect of land use change and land cover change has consequences in the atmospheric circulation, by altering the balance in solar radiation, albedo, soil moisture and texture, aerodynamic roughness and other surface properties.

Oil content and lipid composition of safflower (Carthamus tinctorius) irrigated with saline water under greenhouse and field conditions

Journal Articles & Books
december, 2011
Uzbekistan

An intensive process of land deterioration of some regions in Uzbekistan including the Aral Sea basin has led to a significant increase in soil salinity levels and consequently to a considerable reduction of total fertile soil area, as these lands are of little use for plant growth. The area is estimated to be more than 1.4 million ha of seabed. As a result, there was an immediate need to cultivate new crops capable of stopping the movement of sands and the enlargement of saline soils.

Conservation agriculture (CA) in Tanzania: the case of the Mwangaza B CA farmer field school (FFS), Rhotia Village, Karatu District, Arusha

Journal Articles & Books
december, 2011
Tanzania
Germany

This project was initiated to promote conservation agriculture (CA) in Tanzania so as to improve the food security and rural livelihood of small- and medium-scale farmers through the scaling-up of CA as a sustainable land management (SLM) tool as well as increasing the numbers of SLM-CA farmer field schools (FFS) in communities. The project had two phases from 2004 to 2010. It was funded by a Government of Germany trust fund and implemented by the Food and Agriculture Organization of the United Nations (FAO) and the Ministry of Agriculture in Tanzania.

Deforestation rates in insular Southeast Asia between 2000 and 2010

Journal Articles & Books
december, 2011

Insular Southeast Asia experienced the highest level of deforestation among all humid tropical regions of the world during the 1990s. Owing to the exceptionally high biodiversity in Southeast Asian forest ecosystems and the immense amount of carbon stored in forested peatlands, deforestation in this region has the potential to cause serious global consequences. In this study, we analysed deforestation rates in insular Southeast Asia between 2000 and 2010 utilizing a pair of 250 m spatial resolution land cover maps produced with regional methodology and classification scheme.

role of policies in land use/cover change since the 1970s in ecologically fragile karst areas of Southwest China: A case study on the Maotiaohe watershed

Journal Articles & Books
december, 2011
China

Study of land use/cover change and its driving forces is one of the most significant fields in global environmental change research. Karst land is a type of important and unique terrain on the Earth's surface because of its extensive distribution, impressive landforms, and high ecological fragility. Recently, more and more researchers have realized that irrational land use practices are leading to a series of alarming environmental issues including rocky desertification in karst areas.

Climate-change impact assessment using GIS-based hydrological modelling

Journal Articles & Books
december, 2011

A GIS-based Soil and Water Assessment Tool (SWAT) model is used to assess the impacts of climate change on the hydrological regime of the Cauvery river basin. First, the impact of changes in land-management practices on water availability under present conditions is modelled. Then, the same analysis is carried out under the future climatic scenarios. Finally, annual and monthly precipitation variability is compared under present, as well as future, climate-change scenarios.

empirical approach to estimate soil erosion risk in Spain

Journal Articles & Books
december, 2011
Spain

Soil erosion is one of the most important factors in land degradation and influences desertification worldwide. In 2001, the Spanish Ministry of the Environment launched the ‘National Inventory of Soil Erosion (INES) 2002-2012' to study the process of soil erosion in Spain. The aim of the current article is to assess the usefulness of this National Inventory as an instrument of control, measurement and monitoring of soil erosion in Spain. The methodology and main features of this National Inventory are described in detail.

Factors influencing vegetation cover change in Mediterranean Central Chile (1975–2008)

Journal Articles & Books
december, 2011

Questions: Which are the factors that influence forest and shrubland loss and regeneration and their underlying drivers? Location: Central Chile, a world biodiversity hotspot. Methods: Using land-cover data from the years 1975, 1985, 1999 and 2008, we fitted classification trees and multiple logistic regression models to account for the relationship between different trajectories of vegetation change and a range of biophysical and socio-economic factors.

Quantitative mapping of global land degradation using Earth observations

Journal Articles & Books
december, 2011

Land degradation is a global issue on par with climate change and loss of biodiversity, but its extent and severity are only roughly known and there is little detail on the immediate processes – let alone the drivers. Earth-observation methods enable monitoring of land degradation in a consistent, physical way and on a global scale by making use of vegetation productivity and/or loss as proxies. Most recent studies indicate a general greening trend, but improved data sets and analysis also show a combination of greening and browning trends.

CLIMATE CHANGE AND AGRICULTURAL PRODUCTIVITY IN SUB-SAHARAN AFRICA: A SPATIAL SAMPLE SELECTION MODEL

Policy Papers & Briefs
december, 2011
Africa

Using data at a high spatial resolution, we estimate a cereal yield response function conditional upon climatological and topographical features using a recently developed estimator for spatial process models when sample selection is of concern. We control for localized spatial correlationin unobserved disturbances affecting both the selection to plant cereals as well as in the resulting conditional yield response.