Welcome to Chinese Journal of Applied Ecology! Today is Share:

Chinese Journal of Applied Ecology ›› 2002, Vol. ›› Issue (9): 1085-1090.

Previous Articles     Next Articles

A mathematical model of water stress and light condition effects on cotton dry matter and yield formation

LIU Xianzhao1, KANG Shaozhong2, XIA Weisheng 3   

  1. 1. Department of Geography and Tourism, Yantai Normal College, Yantai 264025;
    2. Institute of Agricultural Soil and Water Engineering, Northwest Science & Technology University of Agricultural Forestry, Yangling 712100;
    3. College of National Land, Hunan Normal University, Changsha 410081
  • Received:2000-09-25 Revised:2000-12-08 Online:2002-09-15

Abstract: Amathematical model was developed to analyze the effects of water stress and light condition on crop dry matter accumulation and yield formation based on canopy carbon net assimilation rate. The function leaf water potential (Ψ1) indicating the water status of canopy was incorporated into this model, according to the assumption that the canopy resistance (Rc) was increased under the conditions of water stress and low light density. Ψ1 was estimated by a simplified regression equation,in which,the independent variables were relative soil moisture (Aw),ambient temperature (Ta),and vapor pressure deficit (VPD). The aerodynamic resistance (Ra) in the model was defined as a function of wind speed (u),and the yield was calculated by a linear increase in harvest index (hi) with time. The modeled data agreed well with the data observed from pot experiment. Sensitivity analysis and simulation results suggested that the model could be useful in identifying environment factors,especially soil water content and light density effects on crop growth and yield formation.

CLC Number: