地理科学 ›› 2014, Vol. 34 ›› Issue (3): 358-364.doi: 10.13249/j.cnki.sgs.2014.03.358

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三江平原沟渠系统水体和底泥的养分特征及效应

郗敏1(), 孔范龙1, 吕宪国2, 姜明2, 李悦1   

  1. 1.青岛大学化学化工与环境学院, 山东 青岛 266071
    2.中国科学院东北地理与农业生态研究所, 吉林 长春 130012
  • 收稿日期:2013-03-21 修回日期:2013-05-10 出版日期:2014-03-10 发布日期:2013-08-16
  • 作者简介:

    作者简介:郗敏(1978-),女,山东泰安人,博士,副教授,主要研究方向为湿地变化及环境效应研究。E-mail:ximin2008@126.com

  • 基金资助:
    国家自然科学基金项目(41101080)、山东省自然科学基金项目(ZR2011QD009、山东省高等学校科技计划项目(J12LC04)资助

Nutrient Variation in Water and Sediments of Ditch Wetlands and Their Effects on Environment in Sanjiang Plain, China

Min XI1(), Fan-long KONG1, Xian-guo LU2, Ming JIANG2, Yue LI1   

  1. 1.College of Chemical and Environmental Engineering, Qingdao University, Qingdao, Shandong 266071, China
    2.Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun, Jilin 130012, China)
  • Received:2013-03-21 Revised:2013-05-10 Online:2014-03-10 Published:2013-08-16

摘要:

分季节原位采集三江平原不同土地利用方式下沟渠系统水体和底泥,调查沟渠水体及底泥中养分的时空分布特征及生态环境效应,分析了土地利用、沟渠植被生长及淹水状况等对沟渠养分时空分异的影响。结果表明,湿地开垦为旱田有利于沟渠DOC的沉积,但降低了沟渠水体DOC的浓度;湿地的垦殖和大量化肥的施用使得旱田沟渠水体TN、TP浓度高于湿地和水田沟渠;而沟渠植被生长和死亡分解又使得沟渠水体及底泥养分呈现出一定的时空差异。养分的长期积累将使沟渠系统水体N/P不断降低,影响湿地生态系统的稳定性。

关键词: 沟渠系统, 养分特征, 生态环境效应, 三江平原

Abstract:

The effect of land use, vegetation growth and flooded condition on spatial-temporal variation of nutrient and eco-environmental effects in two typical ditch systems of Sanjiang Plain, Northeast China, was analyzed through in situ sampling of surface waters and sediments. The results showed that the nutrition of ditch systems mainly came from the farmland and the wetlands in the surrounding area. And the key factors influencing the change of nutrients in sediments and ditch systems include land use, vegetation growth, flooding condition and the degree of blocks. Ditch systems accommodate and purify the runoff from the surrounding farmland and wetland, and reduce the risk of the eutrophication of down stream water body. However, the accumulation of nutrients in ditch systems will bring potential threats to the stability of wetland ecosystem. The land reclamation leads to the reduction of soil DOC storage and the blocking of the ditches can effectively reduce the transport and export of soil DOC. The reclamation from wetland to dry land is beneficial to the accumulation of sediment DOC in ditches, but at the same time, it reduces the soil DOC storage. Therefore, the content of sediment DOC was highest and the ditch water DOC concentrations were lowest in the dry land ditches. The reclamation of Sanjiang Plain wetland and the utilization of large amounts fertilizers made the concentrations of TN and TP in dry land ditch higher than that in the wetland and paddy field ditches. The difference of vegetation growth status made the concentrations of TN in wetland ditch water higher than that in paddy field ditch. Nitrogen and phosphorus accumulated in the plant would be decomposed and released in spring, which made N and P in water increased obviously. The TOC and TN content in the sediments of the ditch systems increased with the decay decomposition of plants in autumn and winter. There is a strong correlation between the flooding conditions of the ditch system and the TOC and TN content in the sediments. The flooding conditions have an indirect impact on the TOC and TN content through influencing the mineralization process of the organic matter and the rate of decomposition or transformation of the total nitrogen. In addition, as a result of the long-term accumulation of nutrients in ditch systems, the concentration of N/P in wetland waters decreases, which will consequently bring potential threats to the stability of the wetland ecosystem.

Key words: Ditch systems, nutrient characteristics, eco-environmental effects, Sanjiang Plain

中图分类号: 

  • X144