[1]SU Mengbai,WANG Keqin,SONG Yali,et al.Characteristics of Runoff, Nitrogen and Phosphorus Losses Under Different Land-use Types in Jianshan River Basin in Middle Yunnan Province[J].Research of Soil and Water Conservation,2020,27(05):24-31.
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Research of Soil and Water Conservation[ISSN 1005-3409/CN 61-1272/P] Volume:
27
Number of periods:
2020 05
Page number:
24-31
Column:
目次
Public date:
2020-08-20
- Title:
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Characteristics of Runoff, Nitrogen and Phosphorus Losses Under Different Land-use Types in Jianshan River Basin in Middle Yunnan Province
- Author(s):
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SU Mengbai, WANG Keqin, SONG Yali, ZHANG Yujian
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(College of Ecology and Environment, Southwest Forestry University, Kunming 650224, China)
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- Keywords:
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land-use types; nitrogen and phosphorus losses; runoff; Jianshan river watershed
- CLC:
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S157.1
- DOI:
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- Abstract:
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Surface runoff causes soil nutrient loss and land productivity decline, and runoff generation characteristics are closely related to land use types. In-depth study of its mechanism can provide scientific basis for soil erosion control, water body protection in the watershed and nitrogen and phosphorus migration rules. In this study, different land use types(plantation, bush, secondary forest, slope farmland)in Jianshan river basin in middle Yunnan Province were selected as the research study sites, and runoff plots with a horizontal projection area of 5 m×20 m were arranged. The runoff amount, patterns of nitrogen and phosphorus loss, concentrations, loss amount and dynamic change characteristics during the rainy season of 2017(May to October)were qualitatively monitored. The results showed that:(1)with the increase of rainfall, the runoff amount of each plots under different land use types gradually increased, and there was a significant correlation between rainfall and runoff amount; the runoff amount in each plot increased in the order: bush<secondary forest<plantation forest<slope farmland;(2)the TN and TP concentrations in different land use types under the condition of rainfall increased in the order: plantation forest(2.39 mg/L)<secondary forest(2.63 mg/L)<bush(2.64 mg/L)<slope farmland(4.00 mg/L), and bush(2.53 mg/L)<secondary forest(4.07 mg/L)<plantation forest(5.72 mg/L)< slope farmland(6.47 mg/L), the concentrations of different forms of nitrogen and phosphorus in runoff significantly increased in slope farmland;(3)dissolved nitrogen and phosphorus were the main pollutants of pollution in runoff water, NO-3-N was the main form of nitrogen loss in runoff, and PO-4-P accounted for 50.91%~77.87% of TP concentration;(4)the total loss of TN and TP increased in the order: bush(0.76 and 0.61 mg/m2)<secondary forests(1.04 and 1.65 mg/m2)<plantation forest(1.36 and 3.60 mg/m2)<slope farmland(7.91 and 15.12 mg/m2). Therefore, in order to alleviate water pollution in Jianshan river basin, the land use type along Jianshan river basin should be adjusted, agricultural activities should be reduced and avoided before rainfall; bush forest area should be increased, bush forest should be set at the outlet of the basin to reduce nitrogen and phosphorus loss in the basin.