生态环境学报Issue(6)：911-918,8.DOI:10.16258/j.cnki.1674-5906.2015.06.001
鼎湖山不同演替阶段森林土壤pH值和土壤微生物量碳氮对模拟酸雨的响应
Responses of Soil pH Value and Soil Microbial Biomass Carbon and Nitrogen to Simulated Acid Rain in Three Successional Subtropical Forests at Dinghushan Nature Reserve
摘要
Abstract
Determining the effects of elevated acid rain on forest soil acidification and soil microbial activity can provide useful information for understanding of the process of carbon and nitrogen cycle of forest ecosystem and its response to global change. Therefore, a simulated acid rain (SAR) experiment was conducted in three subtropical forests of different successional stages [i.e. a young pine forest (PF), a transitional mixed conifer and broadleaf forest (MF), and an old-growth broadleaved forest (BF)] at the Dinghushan Nature Reserve. Acid rain treatments included CK (the local lake water, pH 4.5), T1 (pH 4.0), T2 (pH 3.5), and T3 (pH 3.0) with three replicates. SAR experiment was initiated in June 2009. Responses of soil pH value and soil microbial biomass carbon and nitrogen to the SAR were studied from December 2009 to March 2013. The repeated measures ANOVA showed that, during the study period, the SAR did not affect soil pH value and soil microbial biomass carbon and nitrogen in the PF (P>0.05), but it significantly reduced soil pH value and soil microbial biomass carbon and nitrogen in the BF (P<0.05), and the reduction was marginally significant in the MF. Compared with the CK treatment, mean rate of soil pH valuewere 0.01~0.04, 0.01~0.07, and 0.04~0.10 lower in the acid treatment plots in the PF, MF, and BF, respectively; similarly, mean rate of soil microbial biomass carbon were -1.0%~0.4%, 4.2%~13.6%, and 12.3%~18.4% lower, and mean rate of soil microbial biomass nitrogen were 0.8%~9.7%, 5.4%~17.4%, and 12.3%~25.1% lower in the acid treatment plots in the PF, MF, and BF, respectively. These results indicated the aggravation of soil acidification and the inhibition of soil microbial activity under the SAR in our forests, and more over, the sensitivity of the response of soil acidification and soil microbial activity to the SAR showed an increasing trend with the progressive succession of three forests. In addition, by analyzing the responses of soil pH value and soil microbial biomass carbon and nitrogen of each year, we found that these negative effects had been strengthened over time with significant difference among treatments occurred only in the later period of the experiment. Take the BF for example, treatment effects was not evident in the initial stage of this study. However, after exposing to the SAR for 24, 30, and 36 months, soil pH value of the T3 and T2 treatments were significant lower than the CK and T1 treatments; similarly, soil microbial biomass carbon and nitrogen of the T3 treatment were significant lower than the CK treatment after exposing to the SAR for 24, 36, and 45 months. These results indicated that the acidification and the inhibition of soil microbial activity under the SAR was a gradual process in the forests.关键词
模拟酸雨/土壤酸化/土壤微生物活性/不同演替阶段森林/鼎湖山Key words
simulated acid rain/soil acidification/soil microbial activity/forests of different successional stages/Dinghushan Nature Reserve分类
农业科技引用本文复制引用
梁国华,吴建平,熊鑫,吴小映,褚国伟,周国逸,曾任森,张德强..鼎湖山不同演替阶段森林土壤pH值和土壤微生物量碳氮对模拟酸雨的响应[J].生态环境学报,2015,(6):911-918,8.基金项目
中国博士后科学基金项目（2014M552207）；广东省科技计划项目 （）
