猪粪炭对茶园土壤硝化过程及微生物酶活性的影响

Effects of pig-manure biochar on soil nitrification and soil microbial enzyme activity in tea soils

为探讨猪粪炭对茶园土壤的改良作用,通过35 d的好气密闭培养实验,研究猪粪炭施加对茶园土壤的硝化过程、温室气体N2O排放及土壤微生物酶活性的影响。结果表明:施加猪粪炭可以改善茶园土壤的酸性环境,显著提高土壤pH,使其更适宜茶树的生长;茶树是典型的喜铵厌硝植物,较高的硝铵比不利于茶树的生长,低、中量猪粪炭施加显著增加土壤pH,并未促进茶园土壤的硝化作用,且显著降低土壤N2O累积排放量高达41.2%~58.7%;高量猪粪炭施加显著增加茶园土壤净硝化速率,降低N2O累积排放量62.4%;猪粪炭施加显著提高土壤FDA水解酶、脲酶及脱氢酶活性。研究表明,适量猪粪炭的添加可以改善茶园土壤的酸碱环境和微生物活性,促进土壤的生物化学反应和土壤养分元素的循环,从而提高土壤养分的可利用性和土壤质量。

The aim of the present study was to explore the effects of pig-manure biochar on soil nitrification,N2O emissions,and soil microbial enzyme activity in tea-growing soils by conducting a 35-day aerobic incubation experiment.The results showed that pig-manure biochar reduced the acidity of tea soils by significantly increasing soil pH,making the soil more suitable for tea tree growth.Tea trees typically prefer high ammonium,and high nitrification rates are not conductive to the growth of tea plants.The low and medium(BC1+N,BC2+N)biochar application treatments significantly increased soil pH,while having no significant effects on soil nitrification;the high biochar application treatment significantly increased soil net nitrification rate and reduced cumulative N2O emissions by 62.4%.Biochar application significantly increased the activities of fluorescein diacetate hydrolase(FDA),urease,and dehydrogenase in the soil,indicating that appropriate levels of pig manure-biochar application could decrease soil acidity and increase microbial activity in tea soils,thus enhancing the availability of soil nutrients and improving soil quality.