秦岭地区2种蚂蚁巢内土壤理化性质和微生物量的相关性研究

Correlation of Physicochemical Characteristics and Microbial Biomass Among Nest Soil of Camponotus japonicus and Pachycondyla astute in Qinling Mountains

研究了秦岭牛背梁自然保护区森林生态系统中2种优势蚂蚁(日本弓背蚁Camponotus japonicus和敏捷扁头猛蚁Pachycondyla astuta)的营巢活动对林地土壤理化性质及其微生物量的影响。结果表明:3种不同微生境(日本弓背蚁巢内、敏捷扁头猛蚁巢内及蚁巢外对照)土壤的有机质、全氮、速效氮和速效钾含量均存在显著差异(p<0.05),表现为敏捷扁头猛蚁巢内>日本弓背蚁巢内>巢外土壤;全磷和速效磷的含量虽然无显著差异(p>0.05),但与蚁巢外土壤相比,日本弓背蚁巢内速效磷含量下降了31.41%,敏捷扁头猛蚁巢内速效磷含量下降了15.09%;三者间含水量差异亦存在显著差异(p<0.05),且蚁巢内土壤均较巢外潮湿;pH值差异不显著,但蚁巢内土壤比巢外土壤略显酸性。营巢活动对土壤微生物量也产生明显影响(p<0.05),2种蚂蚁蚁巢内细菌、放线菌及真菌的cfu/g数量均显著大于巢外土壤(p<0.05),而敏捷扁头猛蚁巢内3类微生物cfu/g数量又显著大于日本弓背蚁巢内(p<0.05)。土壤理化性质和微生物量的相关性分析表明:日本弓背蚁和敏捷扁头猛蚁巢内土壤有机质、全氮、速效氮、速效钾含量与其土壤中细菌、放线菌、真菌的cfu/g数量呈显著或极显著正相关;全磷含量与土壤微生物量呈不同程度的正相关;但2种蚂蚁巢内的土壤速效磷含量及pH值则与土壤微生物cfu/g数量呈显著负相关。以上结果表明,蚂蚁的筑巢活动可显著影响其巢内土壤的养分含量和微生物量,致使土壤异质性增强,从而对维持森林生态系统中物质能量循环产生重要的影响作用。

Effects of nest-building activity of dominant ants （Camponotus japonicus and Pawqchycondyla astuta） occurring in Niubeiliang Nature Reserve in Qinling Mountains, China, on physicochemical proper- ty and microbial biomass of the soils were investigated. The results showed that the organic matter, total nitrogen, available nitrogen, and available potassium were significant different among the three different microenvironments （C. japonicus nests, P. astute nests and the bulk soil） （p〈0.05）, while those in P. astute nests were higher than those in C. japonicus nests, and both of them were higher than that in the bulk soil, the total P and available P showed no significant difference, but the available P in the nest of C. japonicus decreased about 31.41% and that in the nest of P. astute decreased about 15.09% comparing with the bulk soil. The soil moisture showed significant difference （p〈0.05）, and the soils in ant＇ nests were more humid than the bulk soil. The pH showed no significant difference （p〉0.05）, but the nest soils were more acidic than the bulk soil. The effects of ants＂ nesting activities on microbe biomass were significant （p〈0.05）, and the cfu/g of bacteria, fungi and actinomycetes in two ant species were all significantly greater than those of the bulk soil, while microbe biomass in nests of P. astute were higher than those in the nests of C. japonicus. The amount of soil organic matter, total N, available N, available K and total P had significantly positive correlation with the cfu/g of bacteria, fungi and Actinomycetes, but the amount of available P and pH had negative correlation with the cfu/g of microbe. Therefore, the nesting activities of ants can prominently influence the soil condition and microbial composition, and lead to the increase of soil heterogeneity, and are helpful for the maintenance of substance and energy recycle in forest ecosystem.