摘要
以大官杨,新疆杨为主的塬面农田防护林可有效的削弱风速,最佳防护区在树高的3至7倍处。林带在春季无叶期可提高农田表面的气温和空气相对湿度;夏季可降低气温,增加空气相对湿度。林带两侧有效防护区内冬小麦与春玉米产量明显高于对照区。同时在林带附近存在严重的胁地现象,尤以树高1倍范围内较明显。胁地的主要原因是树木根系与农作物争夺水分和养分,以及树冠遮荫引起日照减少、光照强度减弱及小气候的变化,以致造成农作物减产。
Benefit of shelterbelt and its influence on crop yields in west region of weibei loess Plateau was studied in this pa-per. The results showed that the shelterbelt was able to weaken wind speed by 22. 2% in spring. The best defensiveeffect place was for from the tree in a distance about 3～7 times of the tree height. The microlimatic conditions wereimproved on both sides of windbreak, so that wheat yield in the fields among the shelterbelts was increased by 11 % ～22%,and the corn by 1. 5% ～ 14. 4% on protected zone The side effects of windbreak was also disscussed. The rea-son of reduction of output in belts was mainly that the roots. of the tree competed soil water with crops and the crowmproduced sunshade.
出处
《水土保持通报》
CSCD
北大核心
1993年第5期39-43,共5页
Bulletin of Soil and Water Conservation
关键词
农田防护林
防护效益
作物
产量
shelterbelt
protect effects side effect of windbreak
