Climate Change and Its Impacts on China’s Agriculture
Institute of Meteorology, CAAS, Beijing 10081
Abstract. There has been an increasing amount of research to improve our understanding of the interaction of climate change with agriculture, and on options to mitigate adverse effects while optimizing benefits of climate change for agricultural production. Greenhouse gas-induced changes of climate would have an important effect on agriculture, with the most severe negative impacts probably occurring in the region of high present-day vulnerability that are at least able to adjust technologically to such effects. It is necessary to assess changes of climate, their causes, and potential future changes, particularly impacts of climate change on agriculture, in order to enhance adaptation to climate change.
Probably the most important consequences of the projected changes in climate for agriculture would stem from higher actual evapotranspiration, primarily as a result of higher temperatures of the air and land surface. The annual mean warming of ground surface would be about 2.5 - 3°C in China (NCAR CCM, 2xCO2 – 1xCO2).
As important for agriculture as possible changes in mean climate may be changes
in the variability of climate, particularly in the frequency of extreme weather
events (such as severe storms, heat waves and damaging frosts) that today exact
a major toll on food output.
Warmer and wetter conditions would increase the potential for higher incidence of heat-related and infectious diseases in tropical and temperate areas.
Increased precipitation intensity, particularly during the summer monsoon, could increase flood-prone areas in temperate and tropical region. There is a potential for drier conditions in arid and semi-arid areas during summer, which could lead to more severe draughts.
Due to the climate change, the main risks of crop productivity would increase. The studies have estimated yield potential of main crops – wheat, rice and maize in China to fallen by 5 – 10% under an equilibrium 2xCO2 climate. The warming may tend to induce a northward extension of the multiple cropping zone.
Among the adaptation measures are: adjust cropping calendar and crop rotation; develop and promote use of high-yielding varieties and sustainable technological applications for southern and southeastern China; adopt heat-resistant crops, water-efficient cultivars with resistance to pests and diseases, soil conservation for central China; adopt suitable crops and cultivars, make optimum use of fertilizers and adaptation of agro-technologies for northeastern China; promote irrigation and water-saving technologies, shift from conventional crops to intensive greenhouse agriculture, protect against soil degradation northwestern China. To improve management in agricultural production, including improve irrigation, fertilizer use; control of pests and diseases, soil drainage and the control of erosion, apply adapted cropping systems and farm infrastructure, should be taken as an integrated measure.
Key Words: Climate Change, Impact, Adaptation.
Watching Slides: www.ami.ac.cn/Sino_UK/workshop/CN-UK-Workshop1.ppt