冬小麦-春玉米间作模式下光合有效辐射特性研究

通过对单作和间作种植模式下作物冠层入射和透射光合有效辐射的观测,研究了不同种植模式下冠层光合有效辐射截获量(IPAR)的日变化规律及其与叶面积指数的关系以及冬小麦对预留行的遮荫作用。结果表明:2种种植模式下光合有效辐射截获量日变化均为双峰曲线;叶面积指数<2时,间作冬小麦日平均光合有效辐射截获量约为单作的50%,叶面积指数>2时,2种种植模式下的日平均光合有效辐射截获量相近;2种种植模式下光合有效辐射截获量与叶面积指数均有较好的相关性;间作冬小麦预留行遮荫率(FS)的日变化为双峰曲线,遮荫率与株高(H)有很好的相关性。

Studies on the characteristics of photosynthetically active radiation under intercropping of wheat and maize

On the basis of observation on the incident and transmitted photosynthetically active radiation(PAR)of the winter wheat canopy under the monoculture and intercropping ways,the diurnal change of interception photosynthetically active radiation(IPAR),the relationship between IPAR and leave area index(LAI),and the shading of the winter wheat were studied.The results show that there is a bimodal curve in the diurnal change of IPAR.When LAI is lower than 2,IPAR of intercropping is about 50% of that of monoculture;when LAI is larger than 2,IPAR is almost equal under two planting ways.In addition,there is a good relationship between IPAR and LAI.The results also show that there is a bimodal curve in the diurnal change of fraction of shading(FS),and a good relationship between FS and height(H).