Abstract:

【Objective】 The objective of this study was to investigate spatial variabilities of soil catalase, invertase, and alkaline phosphatase activities of pear orchard under clean and sod cultivation management systems. 【Method】 With the soil of pear (cv. Dangshansu on P. betulaefolia Bge. rootstock) orchard under clean and sod cultivation models as test materials, the experiment was conducted to evaluate spatial variability of soil catalase, invertase, and alkaline phosphatase activities in between rows and different soil layers (0-60 cm). 【Result】 Each enzyme activity showed difference in between rows of the same soil layer in pear orchard with clean and sod cultivation management systems. Variability of soil enzyme activity was found in the horizontal direction. Soil enzyme activities were also different in vertical soil layers under two culture models. Invertase activity in 0-20 cm soil layer was higher than those in 20-40 and 40-60 cm soil layers in between rows. Catalase activities in 0-20 and 20- 40 cm of soil layers were higher than that in 40-60 cm soil layer between rows. Alkaline phosphatase activity in 20-40 cm soil layer was lower than those in 0-20 and 40-60 cm soil layers in between rows. The activities of three enzymes of sod cover were higher than the performance of clean cultivation in the three soil layers, except that invertase activity of sod cover was lower as compared to that of clean cultivation in 40-60 cm soil layer. Sod cultivation model significantly improved soil alkaline phosphatase, invertase, and catalase activities of pear orchard, and the three enzyme activities increased by 22.94%, 4.75%, and 21.12% compared to clean cultivation, respectively. 【Conclusion】 In clean and sod cultivation models, the three enzyme activities exhibited spatial variabilities, and sod cover increased these enzyme activities than clean cultivation.

Key words: clean cultivation, sod cover, pear orchard soil, enzyme activity, spatial variability