Acta Geographica Sinica ›› 2002, Vol. 57 ›› Issue (4): 389-396.doi: 10.11821/xb200204002

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Nitrogen Elements Transferring Processes and Fluxes under Different Land Use in West Tiaoxi Catchment

LIANG Tao1, ZHANG Xiumei1, ZHANG Shen1, YU Xingxiu2, WANG Hao3   

  1. 1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China;
    2. Institute of Geography and Limnology, CAS, Nanjing 210008, China;
    3. Institute of Resources Science, Beijing Normal University, Beijing 100875, China
  • Received:2002-02-21 Revised:2002-04-08 Online:2002-07-25 Published:2002-07-25
  • Supported by:

    Knowledge Innovation Project of CAS, No. KZCX2-310-04-01; the National Key Basic Research Project of China, No. G1999045710


As the main topic of global environmental change, researches on land use/land cover change (LUCC) have been extensively carried out. Effects of land use/land cover changes on regional ecological environment were one of the top concerns recently. By affecting regional material cycling and energy flows, LUCC has great impact on regional climate, soil, rainfall, and water quality. The study of the influences of LUCC on regional environment, especially on process and flux of nutrient elements and heavy metals in catchment scale, is significant to raise and draw up land use polices in accordance with sustainable development strategies. In this study, five typical land covers in West Tiaoxi catchment were studied on nitrogen loss in artificial rainstorm runoff. Triple duplication experiments have been carried out under the artificial rain condition with an intensity of 2 mmin-1 and lasting 32 minutes in a 3 m2 field. Transportation and flux of various species of nitrogen in runoff and sediment were investigated. The results show that nitrogen loss amount and rate are quite different among five kinds of land covers. The loss of total nitrogen in runoff of mulberry is the largest and that of paddy field is the smallest. Particle nitrogen accounts for 70%~90% of total nitrogen in runoff of various kinds of land covers. Loss of dissolved nitrogen in pine trees is much higher than the other kinds of land covers, which are similar among them. More detailed species of dissolved nitrogen show their respective features among various land covers. Total amounts of nitrogen loss from top 10 cm layer of 5 kinds of soils are estimated as high as 4.66-9.40 gm-2, of which nitrogen loss through sediment of runoff accounts for more than 90%. The rate of total nitrogen loss ranges in 2.68-14.48 mgm-2min-1 in runoff, which is much lower than that of 100.01-172.67 mgm-2min-1 in sediment of runoff.

Key words: land use and land cover change, surface runoff, nitrogen loss, artificial rainstorm