关键词: 粮食安全, 历史时期, 气候变化影响, 中国

Abstract:

It is one of the core themes of the Past Global Change Sciences (PAGES) that to understand the mechanism and process of the past human-climate-ecosystem’s interaction in various spatial and temporal scales in order to improve the understanding of contemporary climate change impacts and adaptation. The topic is also the important theme of historical man/milieu relationships that is a big issue of concern by geographers. In this article, concepts of vulnerability and food security in the regime of Global Changes are used to illustrate historical climate change impact-response processes in China. Corresponding to the food access, food availability and food utilization, the food security of historical China is simplified to three levels of food production safety, food supply safety and food consumption safety. The food production safety was the base of food security which could reflect the social sensitivity to climate change. The food supply safety was the capacity of the society to accommodate the crisis of regional food security which could indicate the social capacity to response the impacts of climate change. The food consumption safety was the final state of food security. The insecurity of food consumption was essential for the occurrence of social instability impacted by climate change. The processes related to the impacts of climate change to grain productivity, food supply production security, individual food security, and social security are discussed. For human society, climate change means the changes of climatic resources or disasters. Impacts of climate change occurred from the direct impact on the grain harvest, then transferred further up to the sub-systems of economy, population and society mainly though the impact-response chain of climate change, agriculture harvest per capita food supply, famine, and social stability. However, the impact-response processes of climate change could not be attributed to a simple causality. The initial impact could be amplified or suppressed in feedback processes affected by many factors in each sub-system, such as arable land, population, policy, foreign forces, and so on. Both people’s spontaneous behaviours and the government's organized policies and operations played very important roles in all steps of adjusting the responses on the impacts of climate change. But each adjustment had its limitation under the given historical condition. The impact of climate change could be positive or negative. To a certain degree, even the negative impacts could be converted into new opportunity for development if right countermeasures were taken. This article has provided a framework on the impact-response processes of historical climate change. Further research should be carried out to measure the processes quantitatively on the base of the framework.

Key words: food security, historical climate change, impact of climate change, China