Meta分析中国保护性耕作对土壤微生物多样性的影响

Effect of conservation tillage on soil microbial diversity in China:A Meta-analysis

为了探明中国不同气候类型、土壤肥力和试验年限下,保护性耕作[免耕秸秆不还田(NT)、传统耕作+秸秆还田(TS)和免耕秸秆还田(NTS)]对土壤微生物多样性的影响,对42项已发表的相关研究进行了Meta分析,以检验土壤微生物多样性对保护性耕作的响应,同时评估了土壤微生物多样性的影响因素。结果表明:与传统耕作相比,保护性耕作显著提高了土壤微生物Shannon和Simpson指数(P<0.05),其中免耕秸秆还田效果最好,增幅分别为8.4%和3.7%;保护性耕作土壤中细菌的Shannon和Simpson多样性指数均高于传统耕作,真菌的Shannon和Simpson多样性指数仅在免耕秸秆不还田下显著增加4.4%和5.3%(P<0.05);土壤微生物多样性在传统耕作+秸秆还田处理下受年均气温和种植作物影响明显,在土壤环境质量较好的非中性土壤中进行免耕处理显著增加土壤微生物多样性(P<0.05),并且在我国北方区域施行免耕对土壤微生物多样性的增加效果较其他区域好。因此,建议在中国北方构建以免耕为核心的保护性耕作技术体系,在不同区域因地制宜的选择秸秆还田管理措施,且进一步对保护性耕作处理下的土壤真菌多样性及更多土壤微生物多样性指数进行相关研究。

A Meta-analysis of 42 published studies was conducted to ascertain the effects of conservation tillage[no-tillage with no straw returning(NT),tillage with straw returning(TS),no-tillage with straw returning(NTS)]on soil microbial diversity under different climatic types,soil quality,and test durations in China.The study examined the response of soil microbial diversity to conservation tillage,and at the same time evaluated the factors affecting soil microbial diversity.The results showed that compared with conventional tillage,conservation tillage significantly improved the Shannon and Simpson indices of soil microorganisms(P<0.05),among which no-tillage with straw returning demonstrated the greatest increase in diversity,with an increase of 8.4%and 3.7%,respectively,compared to the control.The Shannon and Simpson diversity indices of bacteria in conservation tillage soil were higher than those in traditional tillage,and the Shannon and Simpson diversity indexes of fungi increased significantly in no-tillage with no straw returning soil,with an increase of 4.4%and 5.3%,respectively(P<0.05).Soil microbial diversity is significantly affected by annual mean temperature and planted crops under traditional tillage with straw returning.No-tillage treatment in non-neutral soil with better soil environmental quality significantly increased soil microbial diversity(P<0.05),and the effect of no-tillage on soil microbial diversity in the northern region of China was greater than that in other regions.Therefore,it is suggested that a conservation tillage system with no tillage as the core should be constructed in northern China,and straw returning management measures should be selected according to local conditions in different regions.Furthermore,the diversity of soil fungi and more indices of soil microbial diversity under conservation tillage should be studied.