【作者】 何奇瑾；

【导师】 周广胜；

【作者基本信息】 中国气象科学研究院 ， 大气物理学与大气环境， 2012， 博士

【摘要】 针对气候变化背景下我国玉米生产布局及应对气候变化政策制定的需求，根据我国玉米农业气象观测站的地理分布数据和1961~2010年10km×10km空间分辨率的逐日气象资料，结合已有影响作物地理分布的限制因子，从全国范围和年尺度筛选出了影响我国玉米种植分布的潜在气候因子；采用相关性分析方法、最大熵(MaxEnt)模型和ArcGIS空间分析技术，定量评价了潜在气候因子对玉米(春玉米、夏玉米)种植分布影响的贡献，确定了影响我国玉米(春玉米、夏玉米)潜在种植分布的主导气候因子；构建了我国玉米(春玉米、夏玉米)种植分布与气候关系模型，给出了玉米(春玉米、夏玉米)在待预测地区的存在概率，并据此进行了玉米(春玉米、夏玉米)潜在种植分布的气候适宜性划分；进而分析了最近50年玉米(春玉米、夏玉米)潜在种植分布区各主导气候因子的时空变化；探讨了气候变化对我国玉米(春玉米、夏玉米)潜在种植分布的影响。主要结论如下：(1)最大熵模型可以用于玉米种植分布与气候关系研究。不同类型玉米主导气候因子的贡献、重要性排序及影响因子数均不相同：影响玉米(包括春玉米、夏玉米、套玉米)种植分布的主导气候因子有：日平均气温≥10℃的持续日数、≥10℃积温、年均温度、最热月平均温度、年降水、湿润指数；影响春玉米种植分布的主导气候因子有：≥10℃积温、日平均气温≥10℃的持续日数、最热月平均温度、年均温度、年降水、湿润指数和气温年较差；影响夏玉米种植分布的主导气候因子有：年均温度、日平均气温≥10℃的持续日数、≥10℃积温、最冷月平均温度、最热月平均温度、年降水和湿润指数。(2)根据我国玉米(春玉米、夏玉米)种植分布—气候关系模型给出的玉米(春玉米、夏玉米)作物在待预测地区的存在概率(p)，按照p＜0.05为气候不适宜区；0.05≤p＜0.33为气候次适宜区；0.33≤p＜0.66为气候适宜区；p≥0.66为气候最适宜区的划分标准，给出了我国玉米(春玉米、夏玉米)潜在种植分布的气候适宜性等级划分，得到的春玉米可种植北界(52.6°N附近)与实际种植界线基本一致。(3)1961~2010年影响我国玉米(春玉米、夏玉米)种植分布的主导气候因子呈显著的时空变化：全国范围的热量资源均有不同程度的改善，东北地区增加最为显著，且以20世纪90年代前后的变化最明显；水分呈波动式变化，1971~1980年和2001~2010年干旱半干旱区扩大，湿润区的湿润程度低于常年。(4)1961~2010年我国玉米(春玉米、夏玉米)潜在可种植面积呈显著增加趋势。春玉米种植的最适宜区和适宜区明显扩大，近10年气候适宜区总面积达3.4×10~6km~2，潜在可种植界线自70年代开始经历了南移—北抬—维持的变化，最大北抬达1.4个纬度，水分逐渐成为气候变暖背景下作物种植分布的限制因素；夏玉米种植的气候最适宜区东扩、气候适宜区南扩，近10年全国总的可种植面积超过6.7×10~6km~2，可种植区的重心总体呈北移趋势，最大纬向移动达110km。仅考虑气候因素影响时，我国玉米(春玉米、夏玉米)生产还具有很大的潜力。更多还原

【Abstract】 To provide scientific support for planning maize production and making countermeasuresagainst the effects of climate change on maize cultivation, quantitative contribution of thepotential climatic factors on national and annual scale selected from the literature to thegeographic distribution of maize (spring maize, summer maize) cultivation in China wasevaluated, and the major climatic factors affecting maize(spring maize, summer maize)cultivation distribution were determined, in terms of the maize cultivation geographicaldistribution data from the agricultural meteorological observation stations, ChinaMeteorological Administration (CMA) and daily climate data with10km×10km spatialresolution from1961to2010, together with the correlation analysis method, the maximumentropy (MaxEnt) model, and the ArcGIS spatial analysis technique; the suitability formaize(spring maize, summer maize) cultivation in China was given by the existenceprobability obtained from the relationship between maize cultivation distribution and climate;the decadal dynamics of the major climatic factors during the past50years in different suitableareas of maize cultivation were analyzed; and the influence of climate change on the potentialdistribution of maize(spring maize, summer maize) cultivation in China was discussed. Themain conclusions are listed as follows.(1) The MaxEnt model is suitable for revealing the relationship between maize cultivationdistribution in China and climate. The results indicated that the importance, ranks and numbersof main climate controls differ for different maize varieties. The key climatic factors affectingcultivation distribution are duration days of≥10°C,≥10°C accumulated temperature, annualaverage temperature, the warmest month average temperature, annual precipitation, andhumidity index for maize (spring maize, summer maize, intercropping maize);≥10°Caccumulated temperature, duration days of≥10°C, the warmest month average temperature,annual average temperature, annual precipitation, humidity index and annual temperature rangefor spring maize; and annual average temperature, duration days of≥10°C,≥10°C accumulatedtemperature, the coldest month average temperature, the warmest month average temperature,annual precipitation, and humidity index for summer maize. (2) The suitability class of maize (spring maize, summer maize) potential cultivationdistribution was given by the existence probability (p) obtained the relationship betweenpotential maize (spring maize, summer maize) cultivation distribution and climate factors:p<0.05(unsuitable area),0.05≤p<0.33(less suitable area),0.33≤p<0.66(suitable area), andp≥0.66(optimum area), and the north boundary of spring maize cultivation distribution (around52.6°N) is very close to the actual cultivation boundary at present.(3) The dominant climatic factors affecting maize (spring maize, summer maize) during1961-2010showed significant temporal-spatial variation: the thermal resources improvedwith different extents on the national level, the most prominent change occurred in thenortheast China around1990’s; water conditions fluctuated, and the arid and semi-arid regionsexpanded and humid regions became drier during1971-1980and2001-2010.(4) The potential cultivation distrubution of maize(spring maize, summer maize) showedan increasing tendency in China during1961-2010. The optimum and suitable area of springmaize cultivation showed an increase trend, its suitable area reached about3.4×10~6km~2in thelast10years, the northern boundary of spring maize cultivation distribution experienced fromshift southward, through shift northward to steadiness from1970’s, the maximum northwardshift reached about1.4degrees in latitude, implying that climatic change is helpful forenlarging spring maize cultivation, but it might be limited by moisture conditions in some areas;the optimum area of summer maize cultivation distribution moved eastward, and the suitablearea southward. The summer maize cultivation area was more than6.7×10~6km~2in the last10years, its suitable area shifted northward around1990’s, and the maximum shift reached about110km. Thus, the expansion of maize (spring maize, summer maize) cultivation in China ispossible under climatic change.更多还原