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| Structure and Microclimate Effects of Shelter-belt on Farmland in Ningxia |
| Zha Tonggang1,Sun Xiangyang1,Yu Weiping2,Ma Hui2 |
| 1 Beijing Forestry University, 100083, Beijing; 2 Ningxia Forestry Institute, 750004, Yinchuan: China |
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Abstract Through the investigation on the structure and ecological benefits of shelter-belt on farmland in Ningxia and the analysis of comprehensive weight index, that the important roles played by large net, multi-shelter belt and mixed multi-tree-species in the construction of protection forests is explained. The results show that the wind protection effect of shelter-belt on farmland is better when its porosity reaches 35%～45% and its characters determine the law of variation of wind speed. By the redistribution of solar radiation, shelter-belt on farmland has prominent temperature effects on the surface of the soil and plant, which can prevent the crop from heating. Shelter-belt for farmland can increase air relative humidity and soil moisture. The mechanism is related to its wind control function.
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Received: 27 May 2004
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