Nutrient transport associated with water erosion: progress and prospect
Along with the major water erosion process, large amounts of soil nutrient can be transported to water bodies that may degrade the erosion sites and result in water pollution problems in the nutrient-receiving water bodies. Because of the far-reaching ecological and environmental impacts of the nutrient transport processes during water erosion, much research has been done on this topic. The progress of this research topic is reviewed from the perspective of nutrient sources, covering triggers, carriers and forms of nutrient transport, and the factors regulating nutrient transport. Although much progress has been made, challenges still lie ahead. A multidisciplinary and integrative approach, therefore, needs to be taken to resolve the theoretical, methodological and practical problems in water erosion and nutrient transport research. More specifically, the interactions between landscape pattern and nutrient transport processes and spatiotemporal scale and scaling are the two central themes of consideration in methodological integration. It is also important to respect the dynamic and stochastic nature of nutrient transport which is closely related to rainfall-runoff events. The human dimension, formerly a relative weak point in research, needs to be strengthened to gain understanding and a more informed practical control over soil and nutrient loss and conservation.