促生菌剂及有机肥的添加对高寒草甸土壤酶活性的影响

Effects of adding a growth-promoting agent andorganic fertilizer to alpine meadow on soilenzyme activities

摘要:

【目的】 探究促生菌剂及有机肥施用对高寒草甸土壤环境的影响，为促生菌剂在天然草甸中施用及高寒地区草甸生态系统的管理提供理论依据。【方法】 以甘南玛曲高寒草甸为研究对象，设计随机区组研究，设置对照（CK）、促生菌剂（PG）、有机肥（OF）、促生菌剂和有机肥1∶1 配施（PG+OF）4 个处理，通过测定土壤理化性质、微生物量碳（MBC）、微生物氮（MBN）、微生物磷（MBP）和水解酶活性（AP、βG、CBH、βX、NAG），研究促生菌剂及有机肥对高寒草甸土壤酶及酶化学计量比的影响。【结果】 与对照（CK）相比，处理PG、OF 及PG+OF 的电导率显著降低，MBC、N、P 含量显著升高；处理PG+OF 高寒草甸土壤的MBN 含量显著高于其他处理，即促生菌剂和有机肥相互作用显著提升土壤中微生物数量。与CK 相比，处理PG、OF 及PG+OF 显著促进水解酶活性升高，MBC、MBP、MBN、EC 是土壤中酶活性及酶化学计量比变化的重要驱动因子，不同处理间酶化学计量比差异显著。【结论】 促生菌剂及有机肥施用显著增加土壤中微生物数量，增强土壤中微生物活性，且对缓解土壤内碳源、磷源缺失具有正向作用，配施促生菌剂和有机肥对土壤的改良效果最为显著。

Abstract:

【Objective】 To investigate the effects of biotrophic fungicides and organic fertilizers on the soil envi-ronment of alpine meadows，and to provide theoretical basis for the application of biotrophic fungicides in naturalmeadows and the management of meadow ecosystems in alpine areas.【Method】 The alpine meadow in Maqu，Gan-nan served as the research object in a randomized block group study with four treatments： control （CK），biotrophicfungicide（ PG），organic fertilizer（ OF），and biotrophic fungicide and organic fertilizer with 1：1 dosage（ PG + OF）.Four treatments were established to examine the effects of biotrophic agents and organic fertilizers on soil physico-chemical properties，microbial carbon，nitrogen，and phosphorus （MBC，N，and P），as well as hydrolytic enzyme ac-tivities（ AP，βG，CBH，and βX，NAG），and to explore the impacts on enzymes and enzyme stoichiometric ratios in al-pine meadows.【Result】 Compared with the control （CK），treatment with PG，OF and PG+OF significantly re-duced conductivity，while increasing the content of MBC，N and P. The MBN content in the PG+OF treatment wassignificantly higher than in other treatments，indicating a significant interaction between biotrophic fungicides and or-ganic fertilizers that enhanced the soil microbial population. Additionally，compared with the control（ CK），treatmentsPG，OF and PG+OF significantly increased the activity of hydrolases，along with higher levels of MBC，N，and P.Furthermore，compared with CK，treatments PG，OF and PG+OF significantly promoted the hydrolytic enzyme ac-tivity，where MBC，MBP，MBN and EC emerged as important driving factors for changes in enzyme activity and en-zyme stoichiometry ratio in soil. The enzyme stoichiometry ratio displayed significant variations among different treat-ments.【Conclusion】 The application of biotrophic fungicides and organic fertilizers substantially increased the micro-organism count，enhanced microbial activity and positively influenced the alleviation of carbon and phosphorus sourcesdeficiencies in the soil. The combined application of biotrophic fungicides and organic fertilizers demonstrated themost significant impact on soil improvement.?