New modeling framework for describing the effects of landscape pattern changes on nutrient pollution transport

• Published in: The Science of the total environment 2025-01, Vol.959, p.178090, Article 178090
• Main Authors: Zheng, Yuexin, Li, Chong, Wang, Qianyang, Yu, Jingshan, Xu, Shugao, Li, Shuang
• Format: Article
• Language: English
• Subjects: Interception effect; Landscape pattern change; Nutrient pollution; Pollutant transport process; Watershed model
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.178090

Landscape pattern plays a crucial role in regulating hydrological and pollutant migration processes. However, there is a lack of quantitative tools to describe the nutrient pollution transport process under the influence of different landscape patterns. To fill this gap, this study presents a new modeling framework, namely the Landscape Pattern-Source Flow Sink model (LP-SFS). The model consists of three modules: nutrient pollution emission, land transport, and river transport. Each module is implemented using a separate calculation program. It characterizes the transport path of pollutants on landscape units conceptually and operationally and focuses on quantifying the blocking effect of grid-scale landscape units on nutrients. The framework takes the Luanhe River Basin in the North China Plain as an exemplary case. The simulation results of the new framework indicated that in regions predominantly occupied by forest and urban (FU), the intensity of terrestrial pollutant migration attained the highest level. In the slope zone ranging from 25 to 35°, owing to the relatively strong responsiveness of water flow and gravity to the slope, soil erosion is inclined to occur, thereby causing the intensity of terrestrial nutrient pollution transport in this slope zone to reach the maximum value of 4.55 kg/km2. Furthermore, in the elevation zone