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以不同放牧方式下那曲高寒草甸为研究对象,通过比较土壤化学性质和土壤磷脂脂肪酸(PLFA)研究土壤微生物群落结构的变化.结果表明:土壤化学性质(总有机碳、全磷和硝态氮含量)和微生物生物量碳总体表现为休牧7年>自由放牧>禁牧;除真菌细菌比外,土壤PLFA总值、细菌PLFA值、真菌PLFA值、革兰氏阴性菌和革兰氏阳性菌PLFA值均表现为休牧7年>禁牧5年>自由放牧>禁牧7和9年.主成分分析(PCA)表明:第1主成分(PC1=74.6%)主要由单烯脂肪酸、多烯脂肪酸、支链饱和脂肪酸组成;第2主成分(PC2=13.2%)主要由直链脂肪酸和部分单烯脂肪酸组成.土壤微生物生物量碳(MBC)和PLFA总值之间有较好的相关性.与禁牧方式相比,休牧最适宜于那曲高寒草甸健康稳定,轻度放牧也有利于高寒草甸的稳定.
The changes of soil microbial community structure were studied by comparing the chemical properties of soil and PLFA in the Naqu alpine meadow under different grazing patterns.The results showed that the soil chemical properties (total organic carbon, total phosphorus and nitrate nitrogen ), And microbial biomass carbon (SOC), total grazing for 7 years> free grazing> grazing prohibition; total PLFA value, PLFA value, PLFA value, Gram-negative bacteria and Gram- The results of PCA show that the first principal component (PC1 = 74.6%) mainly consists of mono-olefin fatty acid, Polyene fatty acids and branched saturated fatty acids.The second main component (PC2 = 13.2%) consisted mainly of linear fatty acids and some mono-olefin fatty acids.The soil microbial biomass carbon (MBC) and PLFA had better Correlation.Compared with the no-grazing method, Hugh grazing is most suitable for the healthy and stable alpine meadow in Naqu and mild grazing is also beneficial to the stability of the alpine meadow.