Chin J Plant Ecol ›› 2008, Vol. 32 ›› Issue (6): 1346-1355.DOI: 10.3773/j.issn.1005-264x.2008.06.015

• Original article • Previous Articles     Next Articles


WEI Ya-Fen1,2, GUO Ke1,*(), CHEN Ji-Quan1,3   

  1. 1State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
    2Graduate School of the Chinese Academy of Sciences, Beijing 100049, China
    3Department of Environmental Sciences, University of Toledo, Toledo, OH 43606-3390, USA
  • Received:2008-04-07 Accepted:2008-05-30 Online:2008-04-07 Published:2008-11-30
  • Contact: GUO Ke


Aims Soil water is one of the most important factors driving succession in the Artemisia ordosica community in the Ordos Plateau, an arid and semi-arid region of northwestern China. Precipitation is the main source of soil water on the sandland. During each rainfall, part of the rain water is intercepted by plants and the surface layer of soil. This usually quickly evaporates and seems to be biologically ineffective for plant life. Therefore, soil water recruitment is affected by both annual precipitation and characteristics of each rainfall event, such as amount and process. Our objective was to describe the dynamics of soil water content and water recruitment during the growing season.

Methods We used eddy covariance technology to study the process of hydrological balance at the ecosystem scale and considered rainfall and evaportranspiration characteristics.

Important findings In 2006, annual precipitation was about 229.4 mm and rainfall was the main form, mostly occurring from May to October. Rain events differed in rain amount, length of time and intensity. Ecosystem evaportranspiration and rainfall availability were clearly affected by these rain characteristics and other biotic and abiotic factors. Rain events <5.0 mm increased relative humidity and decreased temperature. Rain events >5.0 mm increased soil water in the root layer and were important to community development and stability.

Key words: rainfall pattern, evaportranspiration, soil water, ecosystem