全球变化背景下气候变暖对中国农业生产的影响

全球变化背景下,气候变暖势必对我国农业生产要素、生产环境、农业生产活动及粮食安全产生重大影响。文章采用文献综述与比较研究的方法,系统分析气候变化对我国光资源、温度、水环境和土壤环境等农业生产要素的影响特征及变化趋势,探讨气候变化对我国作物种植区域和种植制度、农作物病虫害、农业生产能力、农业经济与管理等农业生产活动以及农田生态系统过程、农业生态环境(水环境、土壤环境、耕作环境)的实际影响。在此基础上,明确了我国农业在应对气候变化过程中所面临的主要问题:极端气候事件发生频率加大,自然灾害、气象灾害的风险提高,农业生产的波动性增强;农业病虫害的为害时间延长、危害程度加剧、为害范围增大;农业生态环境日趋恶化,农田土壤的干旱化、盐渍化程度加剧,农业生产能力下降;应对气候变化的农业发展策略及其关键技术亟需解决。

IMPACT OF GLOBAL CLIMATIC WARMING ON AGRICULTURAL PRODUCTION IN CHINA

Under the background of global climate change, climate warming is bound to have significant impacts on the factors, environment, activities and safety of agricultural production in China. As the most fragile ecosystem, agriculture is subjected to the most direct impacts from climate change. Climate warming greatly influenced global agro-production and food security under the global environmental change. In past decades, global climate change already made great negative influence on our agriculture and agro-ecosystem, especially the agricultural production in arid regions of North China. Through literature review and comparative studies, the paper systematically summarized influencing trends and effect of climate warming on such agro-production factors as agricultural water resources, light, temperature and soil nutrients. The impact of climate warming on agricultural cultivation structure and crop variety distribution pattern, cropping systems, crop growth and development diseases and pests, weeds, food safety, and structure and function of agro-ecosystem, agro-production capacity, and agro-economy and farm management was analyzed. The results showed that during the past 60 years, the climate warming caused the northwards movement of the northern limits of winter wheat and double rice. The changes may increase the unit grain yield in the changing area. However, the northern limits of rainfed winter wheat-summer maize rotation moved southeast due to the decrease of rainfall. By 2011-2040 and 2041-2050, climate change would cause northward move of northern limits of national cropping system, northward and western move of northern limits of winter wheat, and northward move of northern limits of tropical crops. Yet the increase of future precipitation would make the stable-yield northern limits of rainfed winter wheat-summer maize rotation move northwestward in most regions. On view of agricultural science, the potential issue which the future China's agriculture will face was also discussed in this paper, including the great challenge of low response in productivity to technology application and of high instability of cropland productivity, and most of agricultural meteorological disaster and crop insects became severe with climate warming, in particular, the high frequency of extreme weather events as a great threat to the safety of food production. The future agricultural disasters and pests will be even more frequently, and hence the agricultural production is unstable and sustaining crop productivity and food supply is more difficult.It urgently needs to solve the agricultural development strategy and key technologies to respond to climate change.