| Popis: |
Agricultural non-point source pollution is a major ecological environment issue that seriously affects water safety. A new perspective based on the coupling effects of agricultural spatial-pattern and landscape elements to enhance the ecological function of the agricultural ecosystem and reduce non-point pollution risk was discussed in this study. Firstly, landscape connectivity and landscape heterogeneity should be emphasized to optimize the spatial pattern. Measures such as the building of wetlands, ecological islands, and collecting basins should be fully considered not only to improve animal diversity, strengthen ecological system stability, and reduce chemical pesticide input but also to adsorb and resist the migration of agricultural non-point pollution such as nitrogen and phosphorus, thereby realizing the multi-level utilization of nutrients and extending the space migration way of non-point source pollution. Secondly, enhancing the ecological function of landscape elements was suggested to control non-point pollution. Increasing the proportion of seminatural habitat areas, as well as building ecological ditches and pre-storages, was suggested for varying conditions. To fully consider the coupling function of spatial-pattern and landscape elements in reducing chemical fertilizer and pesticide inputs, agricultural measures such as rational fertilization, compost, rotation and intercropping, and biological control were also suggested. Finally, we took the organic farm in the Songhua dam area as an example to expound the coupling effects of these measures. The animal species were significantly increased and the agriculture service function was elevated; moreover, nitrogen, phosphorus, and pesticide loss were reduced by 820~1 093 kg·hm-2, 273~364 kg·hm-2, and 2.2~2.5 kg·hm-2, respectively. |
