三峡水库消落带土壤养分含量及生态化学计量特征  

Characteristics Soil Nutrient Content and Ecological Stoichiometry in the Littoral Zone of the Three Gorges Reservoir Area

作　　者：孙阔 袁兴中[1,2] 王晓锋 袁嘉[1,2] 候春丽 魏丽景 SUN Kuo;YUAN Xing-zhong;WANG Xiao-feng;HOU Chun-li;YUAN Jia;WEI Li-jing(Faculty of Architecture and Urban Planning,Chongqing University,Chongqing 400044,China;Ecological Restoration and Control of Water Level Fluctuating Zone in the Three Gorges Reservoir Area,Chongqing University,Chongqing 400044,China;Chongqing Key Laboratory of Wetland Science Research Center of the Upper Reaches of the Yangtze River,Chongqing 401331,China;Kaizhou District Nature Reserve Management Center,Kaizhou 405400,Chongqing,China)

机构地区：[1]重庆大学建筑城规学院,重庆400044 [2]重庆大学三峡库区消落区生态修复与治理研究中心,重庆400044 [3]长江上游湿地科学研究重庆市重点实验室,重庆401331 [4]重庆市开州区自然保护地管理中心,重庆405400

出　　处：《长江流域资源与环境》2023年第2期403-414,共12页Resources and Environment in the Yangtze Basin

基　　金：国家自然科学基金面上项目(52178031);中央高校基本科研业务费项目(2021CDJQYJC005)。

摘　　要：作为世界上最大的水利工程,三峡水库的建设和运行对三峡水库消落带土壤环境产生了重大影响。已有研究多关注于三峡库区中某一段消落带或某一支流消落带的土壤环境变化,而缺乏对全库区消落带进行研究。以全库区尺度(8个断面)的不同海拔消落带土壤(155~165和165~175 m)为研究对象,以断面未淹没区(175~185 m)土壤为对比,对土壤养分(土壤有机质-SOM、总氮-TN、总磷-TP、总钾-TK)及生态化学计量(C/N、C/P和N/P)分布特征进行研究。结果表明:(1)消落带SOM、TN、TP和TK的含量均低于未淹没区,而C/N、C/P和P/K的值均高于未淹没区;(2)消落带165~175 m的SOM和TN分别为21.27和1.14 g·kg^(-1),均显著低于155~165 m海拔和对照组相对应的土壤养分含量,而T/N和N/P分别为11.07和2.68,与对照组的土壤化学计量比有显著的差异性,且SOM变异性最小为6%、TP变异性最高为24%;(3)三峡库区全域内,上游(涪陵区)和中游(忠县、万州区、云阳县、奉节县)的土壤养分含量显著高于下游(巫山县和秭归县)地区,且SOM、TN、TP和TK的最高值为忠县和万州区消落带土壤,而库区中上游的土壤养分生态化学计量比显著低于下游,且C/N、C/、PN/P的最低值均为涪陵区消落带土壤;(4)消落带土壤养分及化学计量比的分布特征受到消落带的海拔及采样点环境特征的显著影响,且采样点环境特征的影响程度更大。研究表明,自2010年175 m蓄水后,经历了8年季节性淹没-出露的影响,消落带的养分流失状况依旧存在,其中库区下游及165~175 m的消落带土壤养分保持能力较差,应重点加强该区域和消落带中部高程区土壤保持,以维持三峡水库消落带及水生生态系统健康。As the largest hydroelectric power project in the world,the construction and operation of the Three Gorges reservoir have a significant impact on the soil environment in the littoral zone of the Three Gorges reservoir.Previous studies focused more on the changes of soil environment in the littoral zone of a river section or a tributary of the Three Gorges reservoir,and lacked the understanding of the changes of soil environment in the littoral zone of the whole reservoir area.This study investigated and analyzed the distribution characteristics of soil nutrients and ecological stoichiometry in the littoral zone at the scale of the whole reservoir and at different altitudes(155-165 m and 165-175 m),including soil organic matter(SOM),total nitrogen(TN),total phosphorus(TP)and total potassium(TK)content and stoichiometric ratios(C/N,C/P and N/P)a in the whole reservoir(eight sample sections).The results showed that,1)compared with the unsubmerged area,the contents of SOM,TN,TP and TK in the submerged area of the littoral zone were lower,and the values of C/N,C/P and P/K were higher.2)The contents of SOM and TN in 165-175 m horizontal fluctuation zone were 21.27 g·kg^(-1)and 1.14 g·kg^(-1),which were significantly lower than those of the altitude of 155-165 m and 175-178 m.And the T/N and N/P value in 165-175 m were 11.07 and 2.68,which were significantly different with the unsubmerged area.Besides,the content of SOM and TP were 6% and 24%,which were the lowest and highest variability during all soil nutrients.3)For the whole reservoir area,the soil nutrient content in the upper reaches(Fuling)and middle reaches(Zhongxian,Wanzhou,Yunyang and Fengjie)of the reservoir area is significantly higher than that in the lower reaches(Wushan and Zigui),while the nutrient metering ratio of the upper reaches and middle reaches is significantly lower than that in the lower reaches.The highest value of SOM,TN,TP and TK were found in Zhongxian and Wanzhou district,and the lowest value of C/N,C/P and N/P were found in Fuling distr

关 键 词：消落带 土壤养分 生态化学计量 水位变化 空间分布 三峡水库 

分 类 号：S158[农业科学—土壤学] S154.2[农业科学—农业基础科学]