Climate Change Affects Forest Productivity in a Typical Climate Transition Region of China

Abstract

As global climate change has a large effect on the structure and function of vegetation, it is very important to understand how forests in climate transition regions respond to climate change. The present study investigates the net primary productivity (NPP) of two planted forests (Robinia pseudoacacia and Pinus tabulaeformis) and one natural forest (Quercus wutaishanica) from 1951–2100 using the LPJ-GUESS model in the Shaanxi province of China, which is a typical transition region from humid to dry climates. We found that: (1) Future annual precipitation and mean temperature exhibited nonsignificant and significant increasing trend in the region, respectively, indicating a drier climate in future; (2) although precipitation would increase in the dry area and decrease in the humid area, the NPP of each species in the dry area would be lower than that of the humid area, possibly because increasing temperature and CO2 concentration could restrain forest growth in dry areas and promote forest growth in humid areas; (3) of the three species, P. tabulaeformis forest exhibited the highest average NPP and R. pseudoacacia forest exhibited the highest NPP trend in both dry and humid areas, indicating these planted species may be adaptable to future climate change. Our results provide novel insights into the potential response of forest productivity to a changing climate in the transition region from humid to dry climates.