摘要
理解河流水体氮磷浓度与景观格局之间的关系是流域水环境质量科学管理的前提。选取湖南省长沙县石燕河流域,基于Pearson相关性分析、方差分解分析和多元线性回归方法,研究景观格局对流域出口水体氮磷浓度的影响并构建氮磷浓度预测模型。结果表明,流域出口水质长期处于劣V类,铵态氮(NH_4^+-N)、硝态氮(NO3--N)、总氮(TN)、可溶性磷(DP)和总磷(TP)质量浓度分别为5.67~22.46、0.76~2.85、13.41~45.55、0.86~5.00和1.99~9.94 mg·L^(-1);流域出口水体氮磷浓度与土地利用方式组成、景观格局指数、人口和养殖密度相关性显著(P<0.05)。流域出口水体TN和TP浓度与林地面积比例、养殖密度呈显著正相关(P<0.05),与农田、居民地面积比例和人口密度呈显著负相关(P<0.05);TN和TP浓度与景观格局最大斑块指数(LPI)呈显著正相关(P<0.05),与景观斑块形状指数(LSI)呈显著负相关(P<0.05);流域出口水体氮磷浓度可用土地利用方式组成(农田、居民地、茶园)和景观格局指数[斑块密度(PD)、LPI、LSI、蔓延度(CONTAG)、景观分割度(DIVISION)]的多元线性回归模型预测(校正后R2为0.132~0.320),且多元线性回归模型对NO_3^--N浓度的预测效果最佳。研究结果可为亚热带丘陵区农业流域水环境保护与景观合理规划、利用和管理提供科学依据。
Knowledge about relationships of nitrogen( N) and phosphorus( P) concentrations in river water with landscape pattern is the premise of scientific management of catchment water environment. Shiyan River Catchment,in Changsha County,Hunan Province was selected as the object and Pearson correlation analysis,variation partitioning analysis,and multivariable linear regression analysis were applied to the exploration of effects of land use on N and P concentrations in river water at the catchment outlets and development of a model for predicting quality of the river water. Results show that 1) the water in the outlets has long been ruled into the category of Grade V minus in quality,as specified in the National Standard for Surface Water Quality( GB 3838-2002),with the concentration of ammonium-N( NH_4^+-N),nitrate-N(NO_3^--N),total-N( TN),dissolved-P( DP),and total-P( TP) varying in the range of 5. 67-22. 46,0. 76-2. 85,13. 41-45. 55,0. 86-5. 00,and 1. 99-9. 94 mg·L^(-1),respectively; 2) N and P concentrations in the river water at the outlets of the catchment were significantly related to land use,landscape,population and livestock density( P< 0. 05),significantly and positively to proportion of forest land in area,and livestock density,and significantly and negatively to proportions of farmland and residential settlement in area,and population density. Besides they were also significantly and positively related to landscape maximum plaque index( LPI),and negatively to landscape shape index( LSI); 3) N and P concentrations in the river water could be predicted through analysis of land use patterns( farmland,residential area,tea garden,etc.) and landscape pattern indices [patch density( PD),LPI,LSI,contagion index( CONTAG),and landscape segmentation index( DIVISION)],using the multiple linear regression model( calibrated R2: 0. 132-0. 320).The model worked particularly well for predicting NO_3^--N concentration in the river water. All the findings may serve as an important scientific basis for protection of the wate
出处
《生态与农村环境学报》
CAS
CSCD
北大核心
2017年第6期509-518,共10页
Journal of Ecology and Rural Environment
基金
国家科技支撑计划(2014BAD14B01)
城郊环保型高效农业关键技术研究与示范(2014BAD14B05)
湖南省水利科技项目(湘水科计[2016]-SB-01)
湖南省科协决策咨询研究计划
关键词
流域环境
氮磷
畜禽养殖
面源污染
土地利用
catchment environment
nitrogen and phosphorus
livestock
non-point source pollution
land use
