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对天津周边半干旱地区不同种植年限的菜田土壤微生物状况调查研究表明 ,该地区土壤微生物以细菌为主 ,夏季微生物总量大大高于冬季 ;随着种菜年限的增加 ,耕层和亚耕层微生物总量都有增加趋势 ,其中细菌和放线菌增加明显 ,真菌有下降趋势 ;真菌类群分析表明 ,少数纤维素分解菌 ,如青霉 (Penicillium)、木霉 (Trichoderma)等为优势菌 ,而糖和木质素分解菌仅占少数。用尖孢镰刀霉 (Fusariumuoxysporum)、大肠杆菌 (Escherichiacoli)接种不同种菜年限土壤 ,检测土壤拮抗菌状况发现 ,拮抗菌仅在种植年限长的老菜田的放线菌中发现。表明北方半干旱地区菜田土壤细菌为优势菌 ,主要存在于土壤微孔隙中 ;而适于生活在土壤疏松大孔隙中的真菌数量极少。应注意土壤结构的改良 ,为丰富土壤微生物提供良好的生态环境
The investigation of soil microbial status in vegetable fields with different planting years in semi-arid areas around Tianjin showed that the soil microorganisms in this area were mainly bacteria, and the total amount of microbes in summer was much higher than that in winter. With the increase of planting years, The total amount of microorganism in the layers increased with the increase of bacteria and actinomycetes and the decrease of fungi. The analysis of fungi showed that a few cellulose-decomposing bacteria such as Penicillium and Trichoderma were dominant bacteria , While sugar and ligninolytic bacteria only accounted for a minority. Fusarium oxysporum and Escherichia coli were used to inoculate different-year-old soil to detect antagonistic bacteria in the soil. The antagonistic bacteria were only found in the actinomycetes in the old vegetable field with long-term planting years. The results showed that the soil bacteria in the vegetable field in northern semi-arid area was the predominant bacteria, which mainly existed in the soil micropores. However, the number of fungi suitable for living in the loose soil macropores was extremely small. Should pay attention to the improvement of soil structure, enrich the soil microorganisms to provide a good ecological environment