Résultats de la recherche
Showing items 1 through 9 of 526.
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Library Resource
Vegetation restoration is one of the most common and effective ways to combat desertification and prevent adjacent areas from sand encroachment in many of the desertified regions of the world. However, vegetation restoration in desertified regions is very difficult because of low rainfall, the mobile ground surface, and cost. An effective, low-cost method of afforestation is urgently required. To determine such a method, a 10-year study was carried out in the Jilantai Salt Lake area.
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Library Resource
The purpose of this study is to discover the changes of household employment structure and of business range for those graziers who have to turn to rear sheep in pens as the background of the policy of returning farmland into forest and grassland. The results of this study are as follows: First, after turning to rear sheep in pens, though the graziers have saved time for other work, the time for feeding has increased to the whole year. In addition, the policy that encourages the rearing of sheep in pens has brought about a growing number of sheep graziers.
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Library Resource
Runoff in Haihe River Catchment of China is steadily declining due to climate change and human activity. Determining abrupt changes in runoff could enhance identification of the main driving factors for the sudden changes. In this study, the sequential Mann-Kendall test analysis is used to determine abrupt changes in runoff in eight sub-catchments of Haihe River Catchment, while trend analysis via the traditional Mann-Kendall test for the period 1960-1999 is used to identify the basic trend of precipitation and runoff.
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Library Resource
A multi-disciplinary research with integration of the theory and methods of climatic change and history was carried out in the southern Loess Plateau of China. High-resolution soil-sedimentary data define an abruptly increased climatic aridity at 3100 a B.P. on the southern Loess Plateau. It was caused by a shift from the dominance of the maritime monsoon to the continental monsoon in the East Asia. The marked aridity induced a considerable deterioration of environment and degradation of land resources.
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Library Resource
Afrique du Sud, Brésil, Inde, Chine, Afrique australe
Acacia mearnsii De Wild (black wattle) is an important plantation species for tannin production and woodchip exports in South Africa and Brazil. This study provides an updated overview of the black wattle industries in both countries, including planted areas and land ownership, silviculture and management, bark extract production, woodchip exports, as well as key research and development issues. The current total planted area to black wattle is 110 000 ha in South Africa and c. 170 000 ha in Brazil. In both countries black wattle is mainly cultivated by farmers (c.
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Library Resource
Australie, Brésil, Canada, États-Unis d'Amérique, Inde, Fédération de Russie, Chine
Groundwater vulnerability assessment is an important task in water resources and land management. The most sophisticated among the vulnerability assessment techniques is the GIS-based DRASTIC model. However, despite its popularity, it is marred with excessive subjectivity glitches; little research has been conducted to address the shortcomings associated with this method. This study investigates various issues regarding the application of the GIS-based DRASTIC model through a critical review of relevant literatures.
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Library Resource
China has a large area of inland saline-alkali land, equivalent to 40% of the total cultivated land in the country. The principal features of these lands are high salt content, high pH, and poor soil structure with low water infiltration and poor drainage. These conditions effectively prevent the exploitation of such land for agriculture. In this study, we have compared 17 soil conditioning agents for their abilities to promote seed germination and growth under both laboratory and field conditions.
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Library Resource
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Library Resource
Based on remote sensing monitoring, observations and experiments in wind tunnel and field, aeolian processes and landscape change of the Sonid grassland of Inner Mongolia Plateau in northern China were explored in this paper. Aeolian process was very strong and seriously affected by human disturbances on the Sonid grassland of Inner Mongolia Plateau. Sand transport rate of grassland increased quickly with the increase of desertification severities, especially at the very severe desertification stage of sand sheet emergence.
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Library Resource
Asie, Asie central, Ouzbékistan, Chine, Viet Nam, Arménie, Europe orientale, Moldova, Fédération de Russie
During the past two decades agrarian (‘land and farm’) reforms have been widespread in the transition economies of Eastern Europe, the Caucasus and Central Asia (EECCA), following earlier ones in Asia (China and Vietnam). However, independent family farms did not become the predominant sector in most of Eastern Europe. A new dual (or bi-modal) agrarian structure emerged, consisting of large farm enterprises (with much less social functions than they had before), and very small peasant farms or subsidiary plots.
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