杨粮间作系统小气候水平分布特征研究

A study on distribution law of microclimate factors in poplar-crop intercropping system.

杨粮间作行间小气候观测表明,间作可使农田光照强度、风速和空气相对湿度发生明显变化;同时行间各点(林冠下、林冠外和行中点)光照强度变化较大,且与间作行距和间作年限关系密切,如小行距幼林(行距10m,间作4～6年)遮荫度为31.5％～45.6％,平均31.5％,而大行距成林(行距56m,间作12～14年)遮荫度为7.4％～54.3％,平均18.1％。其他小气候因子行间变化较小,且与间作行距(10～56m)和间作年限(4～14年)关系不密切。

The study on poplar-crop intercropping systems shows that the farm microclimate factors have a great variance because of poplar planted in farmland, of which the solar radiation density, wind speed and air relative humidity are the most and the formers two decrease and the latter increases evidently as well. The solar radiation at different points among rows(the points under tree crown,out of tree crown and in the middle of rows) varies with intercropping year and tree spacing. The sunshade of young trees with smaller spacing is31.5%-45.6%, with an average of 31.5%; but that of mature stands with bigger spacing is 7. 4 % - 54. 3 % , with an average of 18.1 % . The other factors, however, have smaller variance among rows and have little relation with intercropping spacing (10-56m) and years (4-14 year).