Abstract:

To study the issue of food security under climate change and provide scientific basis for the exploitation of climate resources and rational layout of agricultural production, the response characteristics of climatic production potential of different crops to climate change have been revealed, and the carrying capacity of climate conditions for food security under specific cropping structure has been explored. A model for estimating climatic potential production of wheat, maize and rice was established by using the stepwise evaluation method and the dynamic parameters of crop growth. Based on the cropping structure and the relationship between food supply and demand, the carrying capacity of climate conditions for food security was then analyzed in Anhui Province. Results indicated that the spatial distribution characteristics of climatic potential production of different crops in Anhui Province matched well with the pattern of cropping structure, which could make full use of the advantages of climatic resources in different regions. Due to the negative impact of climate change, the climatic potential production declined significantly in Anhui Province. The climatic production potential of wheat, maize, single-cropping rice, and double-cropping late rice decreased significantly with a linear tendency rate of 112, 576, 231, and 167 kg∙hm^-2 per 10 years, respectively. Further, the instability of climate potential production of wheat, corn and single-cropping rice has increased in the main producing areas. The total potential production of grain in Anhui Province is characterized by a high level in the north and a low level in the south, and the contribution of different crops to the total potential production of grain varies due to the combined effect of planting structure and climatic production potential. From a province-wide perspective, the contributions of wheat, single-cropping rice, corn and double-cropping rice were 42%, 32%, 18% and 8%, respectively. Wheat accounted for a major part of the total potential grain production in the northern and along the Huai River. The west along the Yangtze River region was dominated by double-season rice, while the proportion of single-cropping rice could reach more than 60% in the middle Jianghuai and south of the Yangtze River region. Considering factors such as climate production potential, food supply and demand structure and population size, most areas in Anhui Province had climatic conditions that could carry a population size that exceeds the current population, with relative surplus rates of up to 50% or more overall. However, the carrying capacity of climate conditions for food security showed significant spatial variability, and the relative surplus rates of regional climatic capacity decreased from northeast to southwest. To ensure food security, the relationship between food supply and demand need to be adjusted and optimized in the overloaded areas.

Key words: food security, cropping structure, climate change, population scale, self-sufficient rate

摘要：

面向气候变化下的粮食安全问题,揭示不同作物气候生产潜力对气候变化的响应特征,探讨在特定种植结构下气候条件对粮食安全的承载能力,可为气候资源开发利用和农业生产合理布局提供科学依据。采用逐级订正法和作物生长发育动态参数建立了小麦（Triticum aestivum）、玉米（Zea mays）和水稻（Oryza sativa）等粮食作物气候生产潜力的估算方法,基于作物种植结构和粮食供需关系分析了安徽省气候条件对粮食安全的承载能力。结果表明,安徽省不同作物气候生产潜力的空间分布特征与种植结构格局总体匹配度较好,能够较好发挥各地气候资源优势。气候变化对作物生产潜力产生了一定的不利影响,导致玉米、一季稻、双季晚稻的气候生产潜力显著下降,线性倾向率分别为每10年减少576、231、167 kg∙hm^-2,并且近年来小麦、玉米和一季稻主产区的气候生产潜力不稳定性增强。安徽省粮食潜在生产总量呈北高南低的特征,受种植结构和气候生产潜力的综合作用,不同作物对粮食潜在生产总量的贡献不一,从全省来看,小麦、一季稻、玉米和双季稻的贡献依次为42%、32%、18%和8%。小麦贡献了沿淮淮北地区粮食潜在生产总量的主要部分,占比超过50%,沿江西部则以双季稻为主,而江淮之间和江南地区一季稻的贡献可达60%以上。综合气候生产潜力、粮食供需结构和人口数量等因素,安徽省不同地区气候条件所能承载的人口规模大多超过了现有人口数,相对剩余率总体可达50%以上,但其地域分异显著,空间分布总体呈东北向西南递减的格局。为充分保障粮食安全,在部分超载地区需进一步调整优化粮食供需关系。

关键词: 粮食安全, 种植结构, 气候变化, 人口规模, 自给率