放牧对张家界索溪峪景区土壤微生物区系及活度的影响

为了探明旅游对张家界景区土壤微生物的影响,进行了放牧对土壤微生物区系及活度的影响研究。结果表明:放牧显著影响了0～5cm土壤的细菌、放线菌、真菌总数,活动区的细菌和真菌等主要有机质分解菌明显低于缓冲区和背景区,而背景区的放线菌明显高于缓冲区和活动区。在5～15、15～25cm土壤层中,细菌和放线菌总数没有受到放牧的影响,但背景区和缓冲区的真菌总数均显著高于活动区,活动区的细菌在5～15cm土壤中最多,而放线菌和真菌数量均表现为随土壤深度增加而减少的趋势。在缓冲区和背景区土壤中,3类微生物的数量均随土壤深度增加而减少。放牧也对表层土壤中的好气性纤维素分解菌、嫌气性纤维素分解菌、好气性固氮菌、硝化细菌以及反硝化细菌等微生物生理群造成了显著影响。土壤微生物活度随土壤深度增加而降低。在0～5和5～15cm²个土壤层中,缓冲区和活动区的微生物活度均明显高于背景区,而缓冲区的微生物活度与活动区的微生物活度没有显著性差异,微生物活度表现为活动区>缓冲区>背景区;在15～25cm土壤层中,活动区与缓冲区的微生物活度没有显著性差异,缓冲区与背景区的微生物活度没有显著性差异,但活动区的微生物活度明显高于背景区的微生物活度。

Studies on the Effect of Grazing on Soil Microflora and Activities in Zhangjiajie Suoxiyu Scene

In order to probe into the effect of livestock farming, which happened simultaneously with recreational activities,on soil microbes and provide reasonable suggestions for keeping ecological balance,studies on microbial flora and microbial activity in soils from Zhangjiajie Suoxiyu Scene were conducted.The results showed that the number of bacteria,actinomycetes and fungi in 0-5cm layer soil was affected prominently by grazing.The number of bacteria and fungi in 0-5cm layer soil from control zone and buffer zone was much higher than that from active zone.The number of bacteria and fungi in 0-5cm layer soil from buffer zone differed not much from that from control zone prominently.And the number of actinomycetes in 0-5cm layer soil from control zone was much higher than that from active zone and buffer zone.The number of actinomycetes in 0-5cm layer soil from buffer zone differed not much from that from active zone. The number of bacteria and actinomycetes in 5-15cm and 15-25cm layer soils was not affected by grazing.The number of fungi in 5-15 cm and 15-25cm layer soils from active zone was much less than that from other two test zones.The number of bacteria in 5-15cm layer soil from active zone was much higher than that from the other two layer soils,but the number of actinomycetes and fungi decreased with the increase of the depth of soil layer.In control zone and buffer zone, the number of bacteria,actinomycetes and fungi in soil decreased with the increase of the depth of soil layer.At the same time,some special physiological microbes,such as aerobic cellulose decomposing bacteria,aerobic nitrogen-fixing bacteria,denitrifying bacteria,nitrifying bacteria and anaerobic cellulose decomposing bacteria were affected prominently by the grazing activities. Microbial activities in 0-5cm and 5-15cm layer soils from active zone and buffer zone were much higher than those in control zone.Microbial activities in 15-25cm layer soil from active zone were much higher than those from control zone.All these results showed that it is necessary to take measures to protect Zhangjiajie National Forest Park from being destroyed.