玉米轮作对中国西南地区土壤理化性质、酶活性、微生物生物量及微生物群落结构的影响
Effects of Maize-Crop Rotation on Soil Physicochemical Properties, Enzyme Activities, Microbial Biomass and Microbial Community Structure in Southwest China.
作者信息
Wang Puchang, Xie Wenhui, Ding Leilei, Zhuo Yingping, Gao Yang, Li Junqin, Zhao Lili
机构信息
School of Life Sciences, Guizhou Normal University, Guiyang 550025, China.
College of Animal Science, Guizhou University, Guiyang 550025, China.
出版信息
Microorganisms. 2023 Oct 24;11(11):2621. doi: 10.3390/microorganisms11112621.
Introducing cover crops into maize rotation systems is widely practiced to increase crop productivity and achieve sustainable agricultural development, yet the potential for crop rotational diversity to contribute to environmental benefits in soils remains uncertain. Here, we investigated the effects of different crop rotation patterns on the physicochemical properties, enzyme activities, microbial biomass and microbial communities in soils from field experiments. Crop rotation patterns included (i) pure maize monoculture (CC), (ii) maize-garlic (CG), (iii) maize-rape (CR) and (iv) maize-annual ryegrass for one year (Cir1), two years (Cir2) and three years (Cir3). Our results showed that soil physicochemical properties varied in all rotation patterns, with higher total and available phosphorus concentrations in CG and CR and lower soil organic carbon and total nitrogen concentrations in the maize-ryegrass rotations compared to CC. Specifically, soil fertility was ranked as CG > Cir2 > CR > Cir3 > CC > Cir1. CG decreased enzyme activities but enhanced microbial biomass. Cir2 decreased carbon (C) and nitrogen (N) acquiring enzyme activities and soil microbial C and N concentrations, but increased phosphorus (P) acquiring enzyme activities and microbial biomass P concentrations compared to CC. Soil bacterial and fungal diversity (Shannon index) were lower in CG and Cir2 compared to CC, while the richness (Chao1 index) was lower in CG, CR, Cir1 and Cir2. Most maize rotations notably augmented the relative abundance of soil bacteria, including Chloroflexi, Gemmatimonadetes and Rokubacteria, while not necessarily decreasing the abundance of soil fungi like Basidiomycota, Mortierellomycota and Anthophyta. Redundancy analysis indicated that nitrate-N, ammonium-N and microbial biomass N concentrations had a large impact on soil bacterial communities, whereas nitrate-N and ammonium-N, available P, soil organic C and microbial biomass C concentrations had a greater effect on soil fungal communities. In conclusion, maize rotations with garlic, rape and ryegrass distinctly modify soil properties and microbial compositions. Thus, we advocate for garlic and annual ryegrass as maize cover crops and recommend a two-year rotation for perennial ryegrass in Southwest China.
在玉米轮作系统中引入覆盖作物是提高作物生产力和实现农业可持续发展的广泛做法,但作物轮作多样性对土壤环境效益的贡献潜力仍不确定。在此,我们通过田间试验研究了不同作物轮作模式对土壤理化性质、酶活性、微生物生物量和微生物群落的影响。作物轮作模式包括:(i) 纯玉米单作 (CC);(ii) 玉米-大蒜 (CG);(iii) 玉米-油菜 (CR);(iv) 玉米-一年生黑麦草一年 (Cir1)、两年 (Cir2) 和三年 (Cir3)。我们的结果表明,所有轮作模式下土壤理化性质均有变化,与CC相比,CG和CR中的总磷和有效磷浓度较高,而玉米-黑麦草轮作中的土壤有机碳和总氮浓度较低。具体而言,土壤肥力排序为CG > Cir2 > CR > Cir3 > CC > Cir1。CG降低了酶活性,但增加了微生物生物量。与CC相比,Cir2降低了碳 (C) 和氮 (N) 获取酶活性以及土壤微生物C和N浓度,但增加了磷 (P) 获取酶活性和微生物生物量P浓度。与CC相比,CG和Cir2中的土壤细菌和真菌多样性(香农指数)较低,而CG、CR、Cir1和Cir2中的丰富度(Chao1指数)较低。大多数玉米轮作显著增加了土壤细菌的相对丰度,包括绿弯菌门、芽单胞菌门和罗库菌门,而不一定会降低担子菌门、被孢霉门和被子植物门等土壤真菌的丰度。冗余分析表明,硝态氮、铵态氮和微生物生物量氮浓度对土壤细菌群落有很大影响,而硝态氮和铵态氮、有效磷、土壤有机碳和微生物生物量碳浓度对土壤真菌群落有更大影响。总之,玉米与大蒜、油菜和黑麦草轮作显著改变了土壤性质和微生物组成。因此,我们提倡将大蒜和一年生黑麦草作为玉米覆盖作物,并建议在中国西南地区多年生黑麦草进行两年轮作。