关键词: 干旱荒漠风沙区, 沙漠化土地治理, 模式与技术

Abstract:

An integrated controlling pattern of combining four belts was designed and applied to control the desertification land of the demonstration region in Huang-hua-tan of Gulang County, Gansu province. The integrated controlling pattern is comprised of the blocking sand belt, the fixing sand belt, the alive plant barrier blocking sand belt, and the enclosed sand belt. It was demonstrated that this pattern had achieved outstanding protection effect for controlling the desertification lands covered mainly by low shifting dunes. In the demonstration region, the crop area suffering from sand-encroaching had decreased from 37.7% in pre-control to 14.2% in the first year after control, and to 0% in the second and the third year. The mean wind speed at 0.5 m and 1.5 m height behind the protecting system could be reduced by 75.9% and 63.4% respectively in comparison with that in open field. The average sand transportation capacity could be reduced from 2 556.2 mg·cm^-1·h^-1 in front of the protecting system to 3.41 mg·cm^-1·h^-1 behind the system. Calligonum klementzii, Hedysarum scoparium,Ulmus pumila, Elaeagnus angustifolia and Artemisia arenasia had been selected as the available plant species for afforesting in shifting sand dunes and inter-dune lowlands. The clay barrier performed well in 2 m×2 m pattern, the straw and the nylon-net barriers performed well in 1m×1m pattern. In the early period of afforestation, annual plants such as Agriophyllum squarrosum and Suaeda gluace propagated flourishingly, their coverage could be 50.2% and 34.1% respectively, which played role on sand fixation in initial stages. The annual plants were gradually replaced by deep-rooted plants along with artificial plants growing, 3 years later the coverage of Artemisia arenasia could reach 10%.

Key words: arid desert area, desertification land control, pattern and technique