北京城市公园绿地土壤微生物群落碳源代谢活性特征

为深入理解城市土壤微生物碳源代谢活性，以北京城市公园绿地土壤为研究对象，采用Biolog-ECO微平板技术，研究了不同历史年限公园AT（奥林匹克森林公园）、CHY（朝阳公园）、YYT（玉渊潭公园）、TRT（陶然亭公园）、RT（日坛公园）、TT（天坛公园），其建设历史年限分别为8、32、52、317、486、592 a]土壤微生物群落碳源代谢特征.结果表明:北京市不同城市公园绿地土壤微生物利用碳源能力不同，AT的AWCD（平均颜色变化率）显著低于其他历史年限较长的公园（P < 0.05）.不同城市公园绿地土壤微生物群落对不同类型碳源利用能力存在差异，AT土壤微生物对多聚物类碳源代谢能力较强，其他公园绿地土壤微生物对糖类和氨基酸类碳源的利用能力较强，所有公园绿地土壤微生物群落对羧酸类碳源的利用能力相对较弱.AT土壤微生物群落功能多样性显著低于其他公园（P < 0.05）.对土壤微生物群落碳源利用能力进行主成分分析显示，提取与土壤微生物碳源利用相关的主成分的累计贡献率为89.00%，对主成分分离起主要作用的碳源为糖类和氨基酸类物质.冗余分析（RDA）表明，不同城市公园绿地土壤微生物碳源代谢能力的主要影响因素是总碳（TC），但值得注意的是，公园历史年限对不同城市公园绿地土壤微生物碳源代谢能力也有很强的影响. 

Soil Microbial Carbon Metabolic Activity of Green-Land of Urban Park in Beijing

To understand the diversity of soil microbial communities in urban area, the carbon source metabolic activities in the urban parks of different history (AT (Olympic Forest Park), CHY (Sun Park), YYT (Yuyuantan Park), TRT (Taoranting Park), RT (Ritan Park), TT (Tiantan Park), constructed 8, 32, 52, 317, 486, 592 years ago, respectively) were analyzed using Biolog-ECO plates. The results showed that the carbon-source utilization of soil microorganisms were different among different urban parks in Beijing. The AWCD of AT was significantly lower than other parks with longer historical years (P<0.05). The soil microbes mostly used polymers as carbon-source in AT and mainly utilized the carbon-source of carbohydrate, amino acids in other parks. The functional diversity of soil microbial community in AT were significantly lower than that in other parks (P<0.05). Principal component analysis demonstrated that the principal components extracted from 31 carbon sources were related to soil microbial carbon source utilization; the principal components accounted for 89.00% of the total variables variance. The important carbon sources were carbohydrates and amino acids. Redundancy Analysis showed that total carbon (TC) was a key factor that was most highly correlated with soil microbial carbon-source metabolism in different urban parks. Park history has a strong influence on the carbon-source metabolic capacity of soil microorganisms in urban park green-land.