论文部分内容阅读
为探讨外来杂草反枝苋对大豆根际土壤微生物碳源利用和土壤理化性质的影响,比较分析了三种不同物种组成的群落,即单种大豆、单种反枝苋、大豆与反枝苋混种的群落中,反枝苋和大豆根际土壤微生物碳源利用情况和土壤理化性质的变化。结果表明:在大豆开花结荚期,混种大豆根际土壤微生物比单种大豆多利用了3种碳源,混种反枝苋与单种反枝苋相比利用的碳源种类数相同;在大豆鼓粒期,混种大豆比单种大豆少利用了9种碳源,混种反枝苋比单种反枝苋多利用了6种碳源;在大豆成熟期,混种大豆利用的碳源种类总数与单种相同,混种反枝苋比单种反枝苋多利用了4种碳源;在土壤理化性质方面,与单种大豆相比,混种大豆根际土壤的有效氮含量和温度均降低,土壤的有机质含量、pH值、含水量和全氮含量升高,且都在大豆鼓粒期差别最大。说明外来杂草反枝苋的入侵改变了大豆根际土壤的理化性质,影响了其根际土壤微生物碳源利用的能力,进而抑制了大豆的生长。
In order to investigate the effect of exotic weed amaranth on soil microbial carbon source utilization and soil physical and chemical properties in soybean rhizosphere, the community composition of three different species, ie single species of soybean, single species of Amaranthus retroflexus, Changes of Soil Microbial Carbon Source and Soil Physical and Chemical Properties in Amaranth Species Mixed Community, Rhizosphere of Amaranthus retroflexus and Soybean Rhizosphere. The results showed that in the flowering and podding stage of soybean, three kinds of carbon sources were used more than rhizosphere soils in mixed rhizosphere soils. The number of carbon sources used in mixed rhizomes was the same as that of single species of rhododendron. In the soybean bolting stage, soybean hybrids used less carbon than 9 single soybeans. Six hybrid carbon sources were used more than the single species of Amaranthus retroflexus. In the soybean ripening stage, The total number of carbon sources was the same as that of single species, and four kinds of carbon sources were used more than single species of Amaranthus retroflexus. In terms of soil physical and chemical properties, compared with single species of soybean, the available nitrogen Content and temperature of soil were decreased. Soil organic matter content, pH value, water content and total nitrogen content increased. The results showed that the invasion of exotic weed amaranth changed the physical and chemical properties of rhizosphere soils and affected the ability of rhizosphere soil microbial carbon utilization, and then inhibited the growth of soybean.