济南北大沙河流域景观格局与水质的空间分异研究OA

Beidasha River is a large river flowing through Jinan City,with typical characteristics of a riv-er flowing along a"village-town-city"gradient.In this study,Beidasha River was selected for a case study,and we explored the impact of land use changes on water quality in the Beidasha River basin along the urban-rural gradient,aiming to provide a scientific basis for optimizing land use and improving water quality in the study area.A total of 19 sampling points were set in the Beidasha River basin,and ArcGIS software was used to analyze the hydrology and land use.Water quality analysis,the landscape pattern in-dex,and correlation analysis were used to explore the relationship between watershed land use and water quality.Results show that along the village-town-urban gradient,patch density initially increased and then decreased.The higher the degree of urbanization,the greater the degree of landscape fragmentation.The river section in the urban community region exhibited the highest land use richness,along with the high-est landscape diversity and stability.The spatial heterogeneity of water pollution in the Beidasha River ba-sin was significant.Water quality in the mainstem of Beidasha River was better than that in the tributaries,and improved along the village-town-urban gradient.Farmland was the primary land use type in the Bei-dasha River basin and its proportional area steadily decreased along the village-town-urban gradient.Land use composition and landscape patterns were the important factors affecting water quality in the basin,and the landscape index exerted a substantial impact on ammonia nitrogen and nitrate levels.Our results indicate that the impact of urbanization and human activities on water quality can be mitigated by strengthening rational planning and management of land use in the watershed and optimizing the land use pattern of the watershed.