甘肃中东部旱作农业区气候变化特征及其对农业生产的影响-自然地理学专业论文.docxVIP

IV IV 拔节期、抽穗期、成熟期分别提前 1～2d、2～3d、2～7d、2～4d 和 6～7d，春 小麦全生育期天数缩短 3～12d。（7）近 17 年来观测区冬小麦的实际产量呈减少 趋势，主要是由返青期～抽穗期内的干旱缺水及此时的高温二者协同作用导致 的；观测区春小麦实际产量也呈减少趋势，产量的减少主要是由生长季节降水量 减少引起的。（6）气候变暖使研究区冬小麦种植界限向西北扩展，理论上研究区 均已可以种植冬小麦，但冬小麦北移界限只代表平均状况，一个地区种植制度和 种植方式不仅取决于气候条件，还要根据当地具体情况科学决断。 关键词：甘肃中东部旱作农业区， 气候变化， 农业生产， 生育期 PAGE PAGE VI Abstract Agricultural production is closely related with climate change. Good or bad crop growth and yield level in addition to decided on the biological characteristics of the crops and people’s production and business activities, largely dominated by light, heat, water, gas and other climatic factors. Dry farming areas in northwest china rely entirely on natural rainfall, is the sensitive areas of climate change and vulnerable areas of agricultural production. Therefore, grasp the climate change laws of dry farming area in northwest China and fully understand the regions agricultural production which respond to climate change, that has great practical significance to sustainable development of agricultural economy in the region. Based on this, the paper selected Dingxi, Pingliang, Qingyang dry farming areas in the mid-eastern of Gansu province as the research object, using wavelet analysis, kriging interpolation, Mann-Kendall trend analysis and mutation analysis etc., analyzed the agro-climatic resources’s (including light, heat, water, wind resources) status, trends, spatial distribution and the coordination degree among climate elements; On this basis, combined with observational data and statistical date of agriculture, analyzed the changes of crop growth, yield and planting structure in study areas and its effect on the response to climate change. The main findings can be summarized as follows: (1) In the recent 48a, heat resources has increased widely in study area, the range of temperature increase: maximum temperature ＞ minimum temperature ＞ average temperature. ≥ 0℃ accumulated temperature, ≥5℃ accumulated temperature and ≥10℃ accumulated te