摘要
为了探究土地利用优化配置对三峡库区小流域径流过程中磷素流失的影响,选取重庆忠县石盘丘小流域内传统农业模式集水区(CG)和土地利用优化配置后的集水区(EG)为研究对象,分别在两个集水区出口采样,监测降雨事件中径流过程和不同形态磷素,分析土地利用配置对磷流失规律的影响.结果表明:(1)监测的10场降雨径流过程中,EG的ρ[总磷(TP)]均低于CG,两者范围分别为0.09~0.75 mg·L^(-1)和0.13~2.82mg·L^(-1);相对于CG,EG显著降低了TP浓度峰值.(2)EG的TP、可溶性磷(TDP)、无机态磷(DIP)和颗粒态磷(PP)在降雨径流过程中的浓度平均值EMC均较CG低,且EG与CG在TP、TDP和DIP的EMC上均呈现显著差异(P<0.05);降雨径流过程中两个集水区磷流失的主要形式均为TDP,但EG的TDP/TP平均值更大.(3)EG比CG的TP、TDP、DIP和PP的输出负荷降低45%、43%、57%和47%,EG和CG各形态磷素输出负荷均与径流总量极显著相关(P<0.01),CG各形态磷与径流总量线性拟合的斜率为EG的1.66~1.75倍,CG各形态磷素输出负荷对径流量的响应较EG更敏感,且降雨径流过程中单位面积产沙量比单位面积产流量更能引起磷素浓度和输出负荷的差异.优化土地利用配置能有效减少各形态磷素流失,为三峡库区小流域磷流失防控提供参考依据.
In order to explore the impact of optimized land use allocation on phosphorus loss in the runoff process of a small watershed in the Three Gorges Reservoir area,a traditional agricultural model catchment area(CG)and a catchment area after optimized land use allocation in the Shipanqiu watershed in Zhong County,Chongqing(EG)were selected as the research object,sampling at the outlets of the two catchment areas,respectively,to monitor the runoff process and different forms of phosphorus in rainfall events and to analyze the influence of land use configuration on the law of phosphorus loss.The results showed that:(1)in the 10 monitored rainfall and runoff processes,theρ[total phosphorus(TP)]of EG was lower than that of CG,and the ranges of the two were 0.09-0.75 mg·L^(-1) and 0.13-2.82 mg·L^(-1),respectively.Compared with that of CG,EG significantly reduced the peak value of TP.(2)The average EMC of TP,total dissolved phosphorus(TDP),dissolved inorganic phosphorus(DIP),and particulate phosphorus(PP)in the process of rainfall and runoff was lower than that of CG,and EG and CG showed significant differences in EMC of TP,TDP,and DIP(P<0.05);the main form of phosphorus loss in the two catchment areas in the process of rainfall and runoff was TDP,but the average TDP/TP of EG was larger.(3)The output load of EG was 45%,43%,57%,and 47%lower than that of the TP,TDP,DIP,and PP in CG.The output load of EG and CG of various forms of phosphorus was significantly correlated with the total runoff(P<0.01).In addition,the slope of the linear fitting of various phosphorus forms in the CG catchment area to the total amount of runoff was 1.66 to 1.75 times that of EG.The output load of various phosphorus forms of CG was more sensitive to runoff than that of EG,and the output per unit area in the process of rainfall and runoff was more sensitive than that of EG.The amount of sand could have caused the difference in phosphorus concentration and output load more than the output per unit area.Optimizing land use configuration can effec
作者
周豪
陈方鑫
罗义峰
龙翼
周继
王小燕
李丹丹
陈晓燕
ZHOU Hao;CHEN Fang-xin;LUO Yi-feng;LONG Yi;ZHOU Ji;WANG Xiao-yan;LI Dan-dan;CHEN Xiao-yan(College of Resource and Environment,Southwest University,Chongqing 400752,China;Institute of Mountain Hazards and Environment,Chinese Academy of Sciences and Ministry of Water Resources,Chengdu 610041,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2022年第7期3597-3607,共11页
Environmental Science
基金
重庆市技术创新与应用示范(社会民生类重点研发)项目(cstc2018jscx-mszdX0061)。
关键词
三峡库区
集水区
降雨径流
土地利用优化配置
磷流失
Three Gorges Reservoir area
catchment area
rainfall runoff
optimal allocation of land use
phosphorus loss