起垄-施肥模式对极度退化高寒草甸土壤理化及酶活性特征的影响

Effects of ridge-fertilization mode on soil physicochemical properties and enzyme activity of degraded alpine meadow

摘要:

【目的】获得极度退化高寒草甸土壤快速修复模式。【方法】选用甘南藏族自治州碌曲县典型的极度退化高寒草甸为试验地，给于不同的整地措施和施肥处理，混播 70% 垂穗披碱草（Elymus nutans）+30% 燕麦（Avena sativa），分析其对极度退化高寒草甸土壤特性的影响。【结果】1）0~20 cm 土层，土壤有机质、碱解氮、速效磷含量和碱性磷酸酶活性在起垄样地高于平地，20~30 cm 土层，起垄中全磷、碱解氮、速效磷含量和蔗糖酶活性高于平地样地。2）起垄样地 0~10 cm 土层全磷含量在氮肥、 微生物菌剂和氮肥+微生物菌剂处理中均低于不施肥处理；平地样地 0~10 cm 和 20~30 cm 土层，氮肥+微生物菌剂处理土壤全磷、全钾、碱解氮、速效磷含量和碱性磷酸酶、蔗糖酶活性高于单施氮肥或微生物菌剂处理。3）整地和施肥模式互作下，0~10 cm、20~30 cm 土层全磷含量和 10~20 cm 土层碱解氮及有机质含量增加显著。【结论】起垄模式较平地在优化土壤有机质、全磷、碱解氮、速效磷含量和碱性磷酸酶活性方面更具优势，采用起垄与氮肥+微生物菌剂的互补技术可快速提高有机质、全磷、碱解氮含量和碱性磷酸酶活性。

Abstract:

【Objective】 In order to obtain a rapid soil restoration model for the extremely degraded alpine meadow. 【Method】 a typical extremely degraded alpine meadow in Luqu County，Gannan Tibetan Autonomous Prefecture was elected as the test site. Different soil preparation measures，fertilization treatments and then，mixed sowing of 70% Elymus nutans +30% Oat （Avena sativa） were carried out on this meadow. Analysis of its effects on soil properties of extremely degraded alpine meadows was made. 【Result】 The results showed that：1） The soil organic matter，alkaline hydrolyzed nitrogen，available phosphorus content and alkaline phosphatase activity in the 0~ 20 cm soil layer in the ridged plot were higher than those in the flat land . And the contents of phosphorus，alkalihydrolyzed nitrogen，available phosphorus and sucrase activity in the 20~30 cm soil layer in the ridged plot were higher than those of the flat field. 2） Comparing the fertilization modes， the total phosphorus content in nitrogen fertilizer，microbial inoculum and nitrogen fertilizer + microbial inoculant treatment in 0~10 cm soil layer in the ridgedplots， were lower than those with no fertilization treatment. In the 0~10 cm and 20~30 cm soil layers of flat plots， the contents of total phosphorus，total potassium，alkali-hydrolyzed nitrogen，available phosphorus and the activities of alkaline phosphatase and sucrase in soil treated with nitrogen fertilizer and microbial microbial agent were higher than those treated with nitrogen fertilizer or microbial microbial agent alone. 3） Under the interaction of soil preparation and fertilization mode，the total phosphorus content in 0~10 cm and 20~30 cm soil layers and the content of alkali-hydrolyzed nitrogen and organic matter in 10~20 cm soil layers increased significantly.【Conclusion】 Ridging mode has more advantages than flat land in optimizing soil organic matter，total phosphorus，alkali-hydrolyzed nitrogen，available phosphorus and alkaline phosphatase activity. The complementary technology of ridging and nitrogen fertilizer + microbial agent can rapidly increase the content of organic matter，total phosphorus，alkali-hydrolyzed nitrogen and alkaline phosphatase activity.