Effects of straw mulching on soil nutrients in mature tea plantation

【Objective】The effects of straw,corn straw and bagasse on soil nutrient,soil pH value,soil water content,yield and physicochemical compositions of fresh tea leaves were studied to screen out the optimal mulching material and provide theoretical references for the sustainable development of tea plantation. 【Method】In mature tea garden,four treatments viz., straw mulching,corn straw mulching,bagasse mulching and blank mulching were carried out, and the thickness of the mulching was the same(8 cm). The soil organic matter,soil alkali-hydrolysable nitrogen, soil available phosphorus,soil available potassium,soil moisture content,yield of fresh tea leaves and tea physicochemical compositions were determined under different treatments. 【Result】Covering straw,corn straw and bagasse could increase the content of available phosphorus,available potassium and organic matter in 0-60 cm soil layer. Covering straw and corn straw could increase the content of alkali-hydrolysable nitrogen in 0-40 cm soil layer,while covering bagasse could make 0-60 soil alkali-hydrolysable nitrogen content decrease,and soil pH value increase. In summer and autumn,soil moisture content after being covered was higher than that of CK. In spring,soil moisture content being covered with straw was higher than that of CK, too. Compared with the CK, the yield of fresh leaves with application of straw and maize straw went up by 13.42% and 9.47%, but went down by5.26% in bagasse. With the three kinds of mulching materials, tea polyphenols content increased, while amino acid content decreased.【Conclusion】Straw and corn straw mulching improved soil nutrient supply and increased tea yield.