Climate change impacts on root herbivores

There is a general consensus among scientists that the earth's climate is currently changing at a more rapid pace than at any point in its history, due to anthropogenic activity (IPCC, 2007). The average mean surface temperature increased by 0.6°C in the 20th century, the occurrence of unusually warm years has also increased, snow cover has decreased and there have been regional changes in rainfall patterns (Houghton et al., 2001). Since industrialization, the concentrations of gases such as carbon dioxide (CO 2 ) and methane (CH 4 ) in the atmosphere have increased, due to the burning of fossil fuels and changes in land use. For example, the average global atmospheric concentration of CO 2 increased by >30% from 280 ppm in 1750 to 360 ppm in 2000 (Houghton et al., 2001), and is predicted to increase further to between 700 and 1000 ppm by the end of the 21st century (Meehl et al., 2007). The build-up of greenhouse gases, such as CO 2 , traps more solar energy in the lower atmosphere, and is one of the main causes of climate change (Hulme et al., 2002).