施用生物炭对燥红土基本理化性质及酶活性的影响

Effects of Biochar Application on Basic Physicochemical Properties and Enzyme Activities of Dry Red Soil

【目的】为探究燥红土对不同类型生物炭及施入量的反应,对其基础理化特性及酶活性进行测定,以期为热带地区燥红土的改良提供理论支撑和依据。【方法】以燥红土为研究对象,设置水稻壳(A)、花生壳(B)两种生物炭类型,生物炭施用量设置为10、20、40和60 t hm^(-2),以不施生物炭为对照(CK),共计9个处理,27个小区。在生物炭施用一年后对0~30 cm土壤进行取样,用于土壤有机碳、全氮、有效磷、速效钾和含水量以及酶活性的测定。【结果】水稻壳生物炭和花生壳生物炭施用后燥红土养分含量和酶活性有显著改变,其中土壤养分含量和含水量在所有土层均随施用量的增加呈明显升高趋势,60 t hm^(-2)生物炭处理对燥红土有机碳、全氮、有效磷、速效钾和土壤含水量显著高于其他处理,分别比对照处理高56.84%~140.22%、19.06%~62.92%、26.57%~54.57%、46.31%~135.12%和27.95%~55.28%;土壤蔗糖酶、酸性磷酸酶和过氧化氢酶活性随施用量增加都有不同程度升高,特别是60 t hm^(-2)花生壳生物炭处理对土壤蔗糖酶活性提升尤为显著。土壤脲酶活性在10~20 cm和20~30 cm土层随生物炭施用量增加呈显著降低趋势。【结论】施用生物炭对燥红土养分含量、土壤含水量和酶活性有明显改善,可施入40 t hm^(-2)以上的生物炭到0~30 cm土层作为燥红土改良的重要添加剂。

[Objective] In order to explore the response of dry red soil to the types and application of biochar, the basic physicochemical properties and enzyme activities in soil were measured. [Method] The biochar of rice hull(A)and peanut hull(B) were selected, and the application rates were set 0(CK), 10, 20, 40 and 60 t hm, respectively.There were 9 treatments and 27 plots in total. One year after biochar application, 0-30 cm soil was sampled for the determination of soil organic carbon, total nitrogen, available phosphorus, available potassium, water content and enzyme activity. [Result] The results showed that the nutrient content and enzyme activities of dry red soil were significantly changed after the application of rice shell biochar and peanut shell biochar, and the content of soil nutrients and moistures were significantly increased with the raising biochar rates in all soil layers. The contents of soil organic carbon, total nitrogen, available phosphorus, available potassium and soil moisture in dry red soil treated with60 t hmbiochar were significantly higher than those of other treatments. The activities of sucrase, acid phosphatase and catalase increased with the raising rates of biochar application in various degrees. In particular, the treatment of 60t m^(-2) peanut shell biochar increased soil sucrase activities significantly. And soil urease activities declined with the increasing rates of biochar in 10-20 cm and 20-30 cm. [Conclusion] Tthe application of biochar can significantly improve the nutrient contents, soil water content and enzyme activities of dry red soil. More than 40 t hmbiochar can be applied to 0-30 cm soil layer as an important additive for the improvement of dry red soil.