Abstract:Based on the spring maize cultivation geographical information from 216 agricultural meteorological observation stations of China Meteorological Administration, climate data with 10km×10km spatial resolution from 1971 to 2000 in China, and the potential climate indices at national and annual scales influencing maize cultivation distribution from the references, together with the maximum entropy (MaxEnt) model as well as ArcGIS spatial analysis technique, the relationship between potential spring maize cultivation distribution and climate and the climatic suitability regionalization of potential spring maize cultivation in China were studied in this paper. The results show that the MaxEnt model is able to develop the relationship between potential spring maize cultivation distribution and climate. The key climatic factors affecting spring maize cultivation distribution include ≥10℃ accumulated temperature, duration days of ≥10℃, the warmest month average temperature, annual average temperature, annual precipitation, humidity index and annual temperature range. The climatic suitability regionalization of potential spring maize cultivation in China was given by the existence probability from the relationship between potential spring maize cultivation distribution and climate. According to the statistical principles and the description of probability from the Fourth Assessment Report of the International Panel on Climate Change (IPCC), the suitability class of spring maize cultivation distribution was given by the existence probability (P): P<0.05 (unsuitable area), 0.05≤P<0.33 (less suitable area), 0.33≤P<0.66 (suitable area), and P≥0.66 (optimum area). The optimum area of spring maize was approx. 5% of the total land area in China, included midwest and northeast parts of Heilongjiang province; midwest part of Jilin province; Liaoning province; parts of Hebei, Shanxi, Shannxi provinces, Inner Mongolia Autonomous Region (Inner Mongolia for short) and Xinjiang Uygur Autonomous Region (Xinjiang for short). The suitable area of spring maize was approx. 30%, which included south of Heihe city in Heilongjiang province; Jilin province except its east part; most parts of Hebei, Tianjin, Shanxi, Shannxi, Shandong, Hubei, Jiangsu, Guizhou, Chongqing provinces and Ningxia Hui Auonomous Region (Ningxia for short); Tongliao, Chifeng, Hohhot and Erdos in Inner Mongolia; middle and south Gansu province; Sichuan basin; small parts of Henan, Anhui, Hunan, Yunnan provinces and Guangxi Zhuang Autonomous Region (Guangxi for short); Shannan district of Xizang (Tibet) Autonomous Region (Xizang for short). The less suitable area was approx. 34%, mainly included south Huma county in Heilongjiang province; west Inner Mongolia; north Gansu; most parts of the South Yangtze River Regions and South China; most parts of Xinjiang and Yunnan provinces. The unsuitable area of spring maize was approx. 31% of the total land area in China, which included north part of 52.6°N; east Inner Mongolia; east Jilin province; Qinghai-Tibet Plateau and high latitude areas of Xijiang. The north boundary of spring maize cultivation distribution given by P≥0.05 was around 52.6°N, and it is very close to the actual cultivation boundary at present. Furthermore, the climatic characteristics of different climatic suitability zones of potential spring maize cultivation were discussed. The actual distribution of spring maize cultivation in China depends not only on climate, socio-economic conditions, and local production technologies, but also on soil type, geographic characteristics, crop varieties, human activity and so on, especially in relation to its yield and economic value. This research provides scientific support for planning spring maize production and designing the countermeasures against the effects of climate change on spring maize.