Study On The Eco-Environmental Impacts Of Interplanting Grass In Apple Orchards

A study on the orchard microclimate,soil water and nutrients were carried out in the apple-interplangting-grass system at one of LuoChuan apple experimental research base in WeiBei plateau,the result showed that:: 1 Orchard with interplanting grass measurement system had the ability to improve orchard inner air humidity , decreased the soil surface sunlight receiving intensity ,and cut down orchard 0~20cm layer soil temperature in the summer, its also reduced the range of air and soil surface layer temperature change during the time of a day or one year. The interplanting grass system created better micro-environment which benefit for apple trees to growth., but the system of different sod species or differ year have differ impacts on the microclimate , The same sod grass with longer planted can improve its microclimate impacts, while lolium perenne system was better than white clove system. 2 Sod cultivation improved soil structure by increasing soil total potosity and capillary porosity in the 0~60cm , and decreasing soil bulk density at 0~40cm layer , promoting conglomeration microaggregate soil particle formation but different cultivation had different impacts on the soil physical prosperity . 3 Sod cultivation increased soil surface layer organic matter and improved soil nutrient transform ratio. And the improving effect of leguminous was better than gramineous planting grass while soil layer deep down. Compared with clearance cultivation , the sod part plot occurred nutrient competition between apple tree and herbage which resulted in decrease soil total N,total P and total K content , but could obviously increase the available N,P and K, so sod cultivation enhanced the actually capability of orchard soil serve fertility. And different species system had differ effects on the nutrient element ,The improving available P capability of gramineous system was stronger than leguminous , but the improving N ability was less than leguminous . 4 In the sod cultivation systems ,the soil trace element content increased in the surface layer but decreased in the deep layer compared with CK. The :Lolium perenne sod system had reduced more trace content in the deep layer while White Clover improve more at surface layer than Lolium perenne . 5 Orchard soil with sod cultivation increase upper layer Catalase activity comparing clearance cultivation system by 0.7%,4.85,1.2% and 5.5%, and also improved Invertase and Urease activity .there appeared different impacts on protease with herbage species, the protease activity increased with lolium perenne system but decreased with white clover system. 6 In the sod cultivation system, the soil water storage capability improved , enhanced soil water use efficiency and improved the regulate soil water use ability , The water storage capability obviously increased with sod cultivation especially in the 60~100cm layer but interplanting grass would result in soil water competition with apple trees., and soil average water storage in 0~100 layer reduced more than CK .