Abstract: In order to assay the impact of high-pressure water-saving deep fertilization on soil nutrient and enzyme activity,we detected the content of soil organic matter,nitrate,phosphorus,potassium,and enzyme activities in the depth of 0 to 60 cm soil layers after five years of high-pressure water-saving deep fertilization(HWSD)experiment in contrast with traditional watering and fertilization method(TWF).The results showed that the content of the soil nitrate,and potassium and enzyme activities increased at the depth of 30 to 60 cm with HWSD when compared with TWF,the organic matter and phosphorus did not change.The activities of urase,proteinase,sucrase were significantly higher in soil of 0 to 30 cm in depth with HWSD,while polyphenol oxidase and catalase in soil of both two drainage and fertilization way were in the same.In contrast,in the deeper layer(40 to 60 cm),proteinase,catalase and sucrase activity were same in both two treatment,but polyphenol oxidase activity were much higher in HWSD.Furthermore,urase always stayed at a relative lower level no matter which layer of soil in the TWF soil than that of HWSD soil.Correlation analysis between enzymatic activity and quantification of fertilizer ingredients indicated that proteinase,urase and sucrase activities demonstrate significantly positive correlation with total nitrate,potassium and organic matter in soil,but no with effective phosphorus.Catalase exhibits significant relationship with nitrate,potassium,phosphorus and organic matter in HWSD,but only had significant correlation to potassium and organic matter in TWF soils.Polyphenol oxidase had not any significant correlation to any fertilizer in both two experiments.Because of high-pressure water-saving deep fertilization,microorganisms shift lower levels in the soil to exhibit a new enzymatic pattern.These results could provide basic data for utilization and improvement for HWSD techniques.

Key words: High-pressure water-saving deep fertilization, Pear orchard, Soil organic matter, Enzymatic activity

CLC Number: 

• S661.2