不同种植年限桃树根区土壤肥力变异特征

果树根际土壤肥力是果树生长的基础,本研究通过对种植年限为5、10、15、20年桃树根区土壤理化和生物学性状变化进行分析,以期揭示不同种植年限桃园根际土壤肥力的变异特征,探明影响桃树产量和品质主要土壤肥力因子,为不同种植年限桃树生产管理提供理论依据。结果表明：随着种植年限的增加,土壤粘粒、粉粒含量增加,但土壤质地未改变;土壤有机质、全氮、有效磷、速效钾含量呈增加趋势;土壤脲酶、过氧化氢酶活性以种植年限15年达到最大值;土壤真菌和细菌数量随种植年限增加呈减少趋势;土壤微生物量氮含量逐年降低。土壤肥力因子之间存在一定相关性,不同土壤肥力因子间的交互关系影响桃园土壤肥力变化,其中土壤有机质、微生物量碳以及土壤酶活性是影响土壤肥力的主要因素。桃树产量以种植年限15年最大,种植年限超过15年桃品质下降,土壤肥力因子中土壤速效钾、有机质、微生物量碳含量及脲酶活性是影响桃产量和品质（可溶性固形物）的主要因素。

Temporal Variation of Rootzone Soil Fertility in Different Planting Years of Peach Orchards

Rhizosphere soil fertility is the foundation of fruit tree growth. In this study, the changes of soil physical, chemical and biological properties in the root zone of peach trees planted by 5, 10, 15 and 20 years were analyzed, to reveal the change rules of rhizosphere soil fertility in peach orchards with different planting years, and explore the main soil fertility factors affecting peach yield and quality. The study could provide a theoretical basis for peach tree cultivation and management. The results show that with the increase of planting years, soil clay and silt increase, but the soil texture does not change; at the same time, the soil organic matter, total nitrogen, available phosphorus and available potassium present an increasing trends; soil urease and catalase could reach the maximum value in 15 years’ planting; soil fungi and bacteria show a decreasing trend with the increase of planting years; however the microbial biomass nitrogen decreases year by year. Thus, there is a certain correlation between soil fertility factors, and the interactions between different soil fertility factors affect the changes of soil fertility in peach orchards. Soil organic matter, microbial biomass carbon and soil enzyme activity are the main factors affecting soil fertility. Peach yield in 15 years planting is the highest and declines after 15 years planting. Among the soil fertility factors, soil available potassium, organic matter, microbial biomass carbon and soil urease are the main factors affecting the peach yield and quality (soluble solids).