| The main reason of non-point source pollution is the losses of nitrogen and phosphorusin the soil,which lead to water eutrophication.Because types of land, rainfall intensities, kindsof fertilization modes are major influential elements of nitrogen and phosphorus lossesthrough surface flow and interflow,A simulated artificial rainfall-runoff plots monitoringexperiment was carried out to study nitrogen and phosphorus losses through surface flow andinterflow affected by different types of land, rainfall intensities and kinds of fertilizationmodes in HunHe River basin in Liaoning Province, examed the influence of differentinfluential elements on nitrogen and phosphorus losses, provided the basis for prediction andprevention of nutrient loss in the soil, regional environment management and pollutioncontrol.The results indicated that:（1）There are remarkable differences between nitrogen and phosphorus losscharacteristics in surface flow and that in interflow.The output density of nitrogen andphosphorus through surface flow was high in the initial time but tend to be stable withartificial rainfall continuing. The output density of nitrogen and phosphorus through interflowkept relative stable in the whole runoff process.In the whole artificial rainfall process,nitrogen and phosphorus losses by surface flow take a high proportion on cultivated land andgrassland, but take a low proportion in interflow. The differences in nitrogen and phosphoruslosses through surface flow and interflow on cultivated land and grassland showed that soilinfiltration mechanism had large reduction function,especially significant for totalphosphorus in grassland,reaching more than90%.（2） Under different rainfall intensities,the runoff producing of surface flow and interflowshowed significant difference, surface flow produced runoff before interflow, and the runoffwas higher than interflow, which was the main way of farmland runoff output. Compared withlow rainfall intensity（R2）,high rainfall intensity（R1） increase surface flow significantly,butinterflow was influenced by rainfall intensity unsignificantly. Surface flow TN averageconcentration in G1significantly higher than G2,which achieved26.1mg·L-1,but the averageconcentration of interflow TN show: R1﹤R2. Both Surface flow’s and interflow’s TP averageconcentration in R1were higher than R2.Rainfall intensity from0.8mm·min-1to2.4mm·min-1,TN and TP losses increased significantly in surface flow,but were affecttedweaker in interflow.（3）Four treatment models were established:①c ontrol（CK）;②base fertilizer spotapplication（G1）;③base fertilizer spot application+topdressing surface application（G2）;④ base fertilizer spot application+topdressing spot application（G3）.Under different kinds offertilization modes,the runoff producing of surface flow and interflow showed significantdifference, surface flow produced runoff before interflow, and the runoff was higher thaninterflow, which was the main way of farmland runoff output.G2reduced surface runoff,G3increased interflow. Surface flow TN average concentration in G2significantly higher thanother fertilization modes, which achieved59.00mg·L-1, there were small differences betweenother fertilization ways, and the highest average concentration of interflow TN was G3.Surface flow TP average concentration in G1higher than CK,which achieved0.41mg·L-1,butthe average concentration of interflow TP was not increase observably. In the four fertilizationprocessing, nitrogen total loss range from385to814mg, the total loss in all fertilizationtreatments were:G2﹥G3﹥G1﹥CK,and topdressing influence nitrogen losssignificantly.Compared with G2,G3reduced the loss of surface nitrogen, at the same time,itwould not significantly increase interflow nitrogen loss. In the two fertilizationprocessing（①、②）, phosphorus total loss in two fertilization treatments were: G1﹥CK, G1increase phosphorus loss. Compared with CK, G1increase surface flow phosphorus loss,buthad less influence on interflow. |
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