我国平原农区林带胁地效应及其控制措施研究进展

总结了近年来我国农田防护林林带尤其平原农区林带胁地的研究成果,以揭示农田防护林的胁地规律及其影响因素,并探讨克服胁地的措施.分析认为:①我国各地区由于地理位置、自然条件以及树种生物学等的差异,农田防护林的胁地范围也不同,在平原农区其胁地范围按程度大小分别为0～[0.4H,2.0H](H为林带平均高度,胁地程度大小依次为...

Review on negative effects and its control measures of forest belt in plain agricultural areas of China

The paper summarized the research results of farmland shelterbelt on negative effect(output reduction)and its control measures in China in recent years, especially in plain agricultural areas so as to explore the degree of output reduction and its influencing factors, and to find an effective way to reduce the negative effects. The results were as follows:(1) Because of the differences in geographical location, natural conditions and tree species biology, the negative effect distance of shelterbelts was different. But in plain agricultural areas, the negative effect distance of shelterbelts in China was 0~[0.4H,2.0H](H was the average height of shelterbelt. The degree of threatened land was 0.4H, 0.5H, 0.6H,…, 2.0H, etc. The same below.), and the negative effect distance of the most shelterbelts was 0~[0.8H,1.5H].(2) The influence of different direction shelterbelts on the negative effect was different, and if the shelterbelt was north-south direction, the range of the western negative effect was larger that was 0.4H-1.5H;while for east-west direction shelterbelt, the northern range of negative effect was larger that was 0.4H-2.0H. The range and degree of the northern area of the negative effect was the largest, and the southern range of the negative effect was the smallest.(3) Although the east-west direction shelterbelt can reduce the shade area more than the north-south direction shelterbelt, it may not increase the yield.(4) Increasing the distance between the shelterbelt and the farmland, planting narrow canopy tree species, strengthening the pruning and selecting the suitable crops were the most effective methods to reduce the negative effect of crown;the most effective method of reducing negative effect of the root was to cut the root and stick the film.