坡耕地土壤微生物功能多样性对间作体系的响应

Response of soil microbial functional diversity to an intercropping system on slope land in the Loess Plateau

为了明确土壤微生物对间作体系的响应,本研究基于粮草(药)间作定位试验,运用Biolog方法研究间作种植模式下土壤微生物功能多样性特征。结果表明:小麦(Triticum aestivum)||菘蓝(Isatis tinctoria)间作模式可提高土壤微生物碳源利用能力,其AWCD值在0–10 cm、10–30 cm土层分别高于小麦单作26%、29%(培养96 h),且在10–30cm土层两者差异显著(P <0.05),土壤微生物利用基质碳源的能力随着土层深度增加而逐渐降低;与小麦单作相比,间作可以显著提高McIntosh指数和Richness指数,尤以小麦||菘蓝间作效果显著(P <0.05);与单作小麦相比,小麦||菘蓝间作可提高0–30 cm土层土壤微生物对六大类碳源的利用强度,间作体系增强了土壤微生物群落稳定性;糖类碳源的变化在影响土壤微生物群落功能多样性方面起主导作用。间作种植模式可以提高土壤微生物生理活性,促进对土壤碳源的利用,小麦||菘蓝间作效果明显。

To clarify the response of soil microorganisms to intercropping systems, the characteristics of soil microbial functional diversity were studied under an intercropping model using the Biolog method. The results showed that a wheat || Isatis tinctoria intercropping model could improve the utilization of the soil microbial carbon source, and its AWCD value was higher than that of wheat monoculture 26, 29%(96 h). Furthermore, there were significant differences in the 10–30 cm (P < 0.05). The ability of soil microorganisms to utilize the carbon source decreased with increasing soil depth. Compared with wheat monoculture, in wheat || I. tinctoria intercropping, the McIntosh index and richness index were significantly improved. Wheat || I. tinctoria intercropping increased the intensity of soil microorganisms to six kinds of carbon sources. Intercropping systems can enhance the stability of the soil microbial community, and changes in the carbohydrate carbon source play an important role in the functional diversity of the soil microbial community (0 –30 cm). An intercropping planting model can improve the physiological activity of soil microorganisms and promote the utilization of soil carbon sources;the effect of wheat || I. tinctoria intercropping is clear.