半干旱农田生态系统春玉米叶面积及叶生物量模拟的比较研究

采用Modified Logistic模型、Log Normal模型和Modified Gaussian模型,分别对半干旱农田生态系统露地和覆膜春玉米叶面积及叶生物量动态变化进行了模拟研究.结果表明:3种模型均可用于模拟露地和覆膜春玉米全生育期叶面积及叶生物量的动态变化,但模拟效果和精度有所不同,Modified Logistic模型能够很好地模拟露地玉米叶面积及露地和覆膜玉米叶生物量的动态变化,但对覆膜条件下叶面积动态变化的模拟效果较差;Log Normal模型和Modified Gaussian模型能够很好地模拟露地和覆膜条件下春玉米叶面积和叶生物量的动态变化过程,模拟值与实际观察值非常接近,但Log Normal模型因其参数少和参数生物学意义明确,更具适用性.Modified Logistic模型已普遍应用于生物领域,用以描述生物量的增长过程,而Log Normal模型和Modified Gaussian模型是模拟叶面积和叶生物量动态变化的初次尝试,为叶面积和叶生物量的动态变化模拟提供了可选途径.

Evaluation of simulation models of spring-maize leaf area and biomass in semiarid agro-ecosystems

By using the Modified Logistic, Log Normal and Modified Gaussian simulation models,dynamic changes in springmaize leaf area and biomass in semiarid ecosystems under field and film mulching were evaluated. The results show that the models can simulate dynamic changes in spring-maize leaf area and biomass for both field and film mulching in the entire development stage. However,the effects and precisions of the simulations are different. The Modified Logistic model is suitable for leaf area and leaf biomass simulation under field planting,and only leaf biomass under film mulching,but not suitable for dynamic changes in leaf area under film mulching conditions. The Log Normal and Modified Gaussian models can commendably simulate dynamic changes in leaf area and leaf biomass under field planting and film mulching conditions;their predicted values are similar to observed values, but the Log Normal model is more useful because of its fewer parameters and specific biological meaning. Modified Logistic model has been widely applied to biological domain, which describes dynamic biomass processes. But Log Normal and Modified Gaussian models primarily simulate leaf area and leaf biomass, which offer optional approaches for simulating dynamic changes in leaf area and biomass.