多水塘系统水文连通及其对磷输移影响研究进展

多水塘系统是农业流域常见的小型水利工程, 空间交错的沟塘结构导致其水文连通过程复杂多变, 对流域营养盐截源控污影响显著。为强化多水塘系统水文连通对磷输移影响的认知, 以多水塘系统及其水文连通的定义内涵为切入点, 归纳了多水塘水文连通性评估方法; 基于景观格局、水文过程和生物地球化学过程聚焦多水塘系统对磷输移的调控作用; 阐明了水文连通变化通过驱动干湿交替对磷输移环境以及通过调节水分滞留时间对磷输移通量的影响。指出多水塘系统水文连通变化的驱动机制、沟塘滞留效率的尺度扩展、定量模拟和优化调控是未来多水塘系统环境效应研究的重要方向, 以期为保障多水塘水质改善功能提供理论依据。

Hydrological connectivity in multi-pond systems and its impact on phosphorus transport: research progress and perspectives

Multi-pond systems are common small-scale water conservancy projects in agricultural watersheds. The spatially interlaced structure of pond-ditches leads to complex and variable processes of hydrological connectivity, which is of great importance to source reduction and pollution control for watershed nutrients. To better understand the impact of hydrological connectivity on phosphorus transport in multi-pond systems, we summarize assessment methods of hydrological connectivity index in multi-pond systems based on the definition and connotation of multi-pond systems and hydrological connectivity. Landscape patterns, hydrological processes, and biogeochemical processes play an important role in regulating phosphorus transport in multi-pond systems. The impacts of hydrological connectivity on phosphorus transport environment through driving drying-wetting cycles and on phosphorus transport flux by changing water residence time are illustrated. We point out that the driving mechanism of hydrological connectivity changes, scale extension of nutrient retention efficiency, quantitative simulation, and optimal regulation are important directions for future research on the environmental effects of multi-pond systems. This review will provide a theoretical basis for ensuring the water quality improvement function of multi-pond systems.