全球变化知识资源中心

Temperature is a key environmental factor affecting the growth, development, survival and reproduction of insects. Although it is widely known that the relationship between temperature and insect development rate is nonlinear, model-based studies have been conducted to investigate the global warming impacts on insect voltinism using the degree-day approach based on a linear model. In the present study, the wheat armyworm Mythimna sequax (Franclemont) was used as a model organism to test whether voltinism estimated under current and future climate conditions varied among phenological models, locations and climate change scenarios. In general, voltinism increased in different years and climate change scenarios compared with current climatic conditions. The degree-day overestimated the number of generations compared with the nonlinear models and also predicted an increase in voltinism in the entire study area as a result of global warming. Location, phenological model and the interaction between these factors explained 94% of the variance in the estimated voltinism. The results obtained in the present study reveal that the choice of phenological models affects voltinism predictions and that a nonlinear model can be used to understand the effects of climate change on insect voltinism, especially in regions where temperature will reach the upper threshold of a species more often.