摘要
In the Shixia small watershed, twenty experimental plots and two monitoring channels, the residential area and livestock areas were used to monitor the flow, runoff and erosion. Nitrogen and phosphorous concentrations associated with various land uses were analyzed at the same time. The results are presented as follows: (1) TP, TN and COD concentrations of runoff samples in the residential area and livestock areas are nearly 10 times those in other land-use areas. High nutrient loads are associated with village land use, which is due to unsuitable livestock rising. These areas should be treated as the critical areas of non-point source pollution. (2) Different land-use influences intensity the loss of nutrients, especially slope tillings in agricultural land. The amount of nutrient loss from agricultural land per unit is highest, that from forestry is intermediate and that from pastures is lowest. However, in consideration of the variability of land-use areas, agricultural land contributes the greatest to TP and forestry land to TN. (3) The concentrations of TN and TP in sediments from gangues are highest, those in forestry land are intermediate, and those in agricultural land are lowest. Nutrient loss from hilly areas is much greater than from mountainous areas.
In the Shixia small watershed, twenty experimental plots and two monitoring channels, the residential area and livestock areas were used to monitor the flow, runoff and erosion. Nitrogen and phosphorous concentrations associated with various land uses were analyzed at the same time. The results are presented as follows: (1) TP, TN and COD concentrations of runoff samples in the residential area and livestock areas are nearly 10 times those in other land-use areas. High nutrient loads are associated with village land use, which is due to unsuitable livestock rising. These areas should be treated as the critical areas of non-point source pollution. (2) Different land-use influences intensity the loss of nutrients, especially slope tillings in agricultural land. The amount of nutrient loss from agricultural land per unit is highest, that from forestry is intermediate and that from pastures is lowest. However, in consideration of the variability of land-use areas, agricultural land contributes the greatest to TP and forestry land to TN. (3) The concentrations of TN and TP in sediments from gangues are highest, those in forestry land are intermediate, and those in agricultural land are lowest. Nutrient loss from hilly areas is much greater than from mountainous areas.
基金
GrantedbytheMinistryofEducationandBeijingMunicipalScientificNew StarPlan .
