Ditches and ponds are widely used in rural landscapes, forming integrated adaptation systems that play a pivotal role in reducing non-point source (NPS) pollution. However, existing semi-distributed models are not capable of accurately simulating pollution removals of ditches and ponds, resulting in a critical gap in integrating simulation, optimization, and spatial configuration for effective pollution control. To address this issue, the newly developed SWAT-DPS model was integrated with multi-objective optimization to construct an integrated framework for optimizing the layouts of ditches and ponds while effectively balancing environmental and economic benefits. This framework enables more accurate grid-scale simulation of pollution reduction of measures, offering more practical layout solutions. Results showed that implementing vegetated ditches, multiple ponds, and vegetation filter strips could reduce NPS pollutants by 20–60 %. Comparative analysis revealed the costs ranging from 0 to 6.28 × 10⁶ yuan, with all cost levels achieving required reductions in total nitrogen (TN) and total phosphorus (TP). Specifically, TN reductions exceeded 60 % in the medium-cost scheme, while TP reductions reached 60 % similarly in the high-cost scheme. This study provides a flexible framework for evaluating the removal efficiencies of NPS pollution, with fully consideration of the spatial configuration of ditch-pond system.

中文翻译：

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SWAT-DPS 与小型农业集水区沟池系统空间设计优化算法的集成


沟渠和池塘广泛用于农村景观，形成综合适应系统，在减少面源 （NPS） 污染方面发挥着关键作用。然而，现有的半分布式模型无法准确模拟沟渠和池塘的污染清除，导致在集成模拟、优化和空间配置以实现有效污染控制方面存在严重差距。为了解决这个问题，新开发的 SWAT-DPS 模型与多目标优化相结合，构建了一个集成框架，用于优化沟渠和池塘的布局，同时有效平衡环境和经济效益。该框架能够更准确地对减少污染的措施进行电网规模的模拟，从而提供更实用的布局解决方案。结果表明，实施植被沟渠、多个池塘和植被过滤带可以将 NPS 污染物减少 20-60%。比较分析显示，成本从 0 到 6.28 × 10⁶ 元不等，所有成本水平都实现了所需的总氮 （TN） 和总磷 （TP） 的减少。具体来说，在中等成本计划中，TN 减少超过 60%，而在高成本计划中，TP 减少同样达到 60%。本研究为评价 NPS 污染的去除效率提供了一个灵活的框架，同时充分考虑了沟塘系统的空间配置。