【作者】 钞振华；

【导师】 陈全功； 梁天刚；

【作者基本信息】 甘肃农业大学 ， 草业科学， 2004， 硕士

【摘要】 草地植被是我国最重要的植被类型之一，是重要的可更新资源和畜牧业的原料基地，是地球上最大的天然绿色屏障，对于人类的生存和发展起着重要的作用。但是草地的退化向我们敲响了警钟，其中1989～1999年全国退化草地的面积从8667万hm2增加到1.3亿hm2，增加了4333万hm2，草地平均以每年433.3万hm2的速度在退化。草地的退化将导致草地生态系统生产力和NEP（净生态系统生产力）的显著下降，并引发自然资源不断减少和生态环境的恶化。过度放牧和草原垦殖是导致草地退化的主要人为因素。因此，调查天然草地资源，阐明草地数量、质量、生产力状况、利用价值和发展潜力，阐明提高草地生产能力和增加生产经济效益的途径等，对于科学利用和开发草地资源，改良和保护草地，指导畜牧业生产以及制定宏观经济发展战略和生产发展规划等具有极重要的意义。遥感技术在资源调查、环境监测、作物估产、区域规划等领域展示了日渐广阔和不可替代的应用前景。在草地资源方面，国内外很多学者利用LANDSAT的MSS、TM资料及NOAA/AVHRR资料做了大量工作，尤其对草地生产能力的评价。草地载畜量只有按季带的实际利用时间和实际可利用产草量来计算才具有实际意义，但是在检索到的资料里，有关利用遥感技术对天然草地按季节牧场进行生产力评价的研究很少。阿勒泰地区位于新疆维吾尔自治区的最北部，拥有草地毛面积984.24万hm2，可利用草地面积723.93万hm2，是全国重点牧区之一，也是新疆最主要的草地畜牧业基地之一。阿勒泰地区是一个纯牧业区，季节轮牧是该区天然草地传统的利用方式。MODIS时间分辨率（1次/1天或1次/2天）优于TM资料（1次/16天）、SPOT资料（1次/26天），而空间分辨率（250m，500m，1000m）高于NOAA/AVHRR资料（空间分辨率1,100m）。由于发射较晚，而有关MODIS资料在草地资源应用的报道还比较少，尚处于探索阶段。本研究利用ERDAS IMAGINE对MODIS资料进行了处理以便与其它地面资料相匹配。在地面同步测产的基础上，根据从MODIS资料提取的植被指数和地面草产量之间的相关关系回归出阿勒泰天然草地的遥感估产模型。求出阿勒泰地区的草地产量，同时,根据天然草地分级的原则和标准对其进行分级。地区间的差异是导致物流不畅的主要原因，本研究结合GIS技术对该地区的夏、冬、春秋三个场的载畜能力进行了评价。本研究的主要结果如下：(1) 通过提取多时相遥感影像合并的平均植被指数ARNDVI，可以提取一定时段内各个像元的最大值，从而尽可能地减少非朗伯体误差和剩余大气干扰，有助于克服单时相影像中的随机误差。(2) 由实地样方的测产资料和遥感影像上提取的平均归一化植被指数ARNDVI的关系，根据相关性原则回归出阿勒泰地区季节牧场产量的反演模型：春秋场：　y1=137.8311+1.219613x 0≤x≤190　　　　　　　　　　　　　　　y2=-90.3710+1.243571x 255≥x>190 R=0.857 冬　场：　y1=57.31877+0.021251x 0≤x≤121 <WP=5>　　　　　　　　　　　　　　　y2=-579.465+5.148731x 255≥x>121 R=0.867　　　　　　　　　 夏　场：　y1=17.19495+0.411811x 0≤x≤148　　　　　　　　　　　　 y2=-23.9173+1.966378x 255≥x>148 R=0.807 式中y—表示产量，x—表示平均归一化植被指数ARNDVI，R—表示y与x之间的相关性。(3) 本研究调查表明，2002年阿勒泰地区草地总面积为9640504.24hm2，其中3级、4级、5级、6级草地分别占草地总面积的3.46%、34.95%、13.14%、33.26%。该地区的理论载畜量为6584005羊单位，其中夏场理论载畜量1612038羊单位，春秋场理论载畜量3184845羊单位，冬场理论载畜量1787122羊单位。而该地区2002年的实际载畜量为7887390羊单位，超载48.38%，夏场已成为关键场。实际载畜量超载的县有哈巴河县、阿勒泰市、布尔津县、青河县，要控制家畜头数的增加。整体上应从利用“夏场优势”到增加对春秋场、冬场的利用时间，尤其是春秋场的利用时间，缩短夏场的利用时间，从而在阿勒泰地区实行集约化的季节畜牧业。 但限于时间等原因，还有以下一些问题有待进一步研究：(1) 植被指数选取方面 需进一步深入研究植被指数与鲜草产量之间的相关性，以便选取适于阿勒泰地区的MODIS遥感估产植被指数。(2) 应利用更长时间序列的遥感影像，建立阿勒泰草地长期稳定适宜的遥感估产模型，建立草地生态环境安全衡量指标体系和监测预警系统。逐步做到以草定畜，从而使草地的生长与家畜的营养需要相一致，使能流、物流畅通。(3) 过度放牧与气候因素是导致草地退化、沙化主要原因的两种观点。土地利用和土地覆盖变化是全球环境变化研究中一个关键而迫切的课题，阿勒泰地区属于大陆性寒温带气候区，应对该区草地资源进行全面深入的研究。利用遥感影像及地面调查资料，将所监测的草地植被变化与影响草地植被变化因子结合GIS技术，分析它们的空间相关性，探讨草地植被变化机理，阐明影响草地植被变化的驱动力因子及其作用。更多还原

【Abstract】 Grassland is one of the most important vegetation forms in China. It is an important renewal resource and raw material base for the animal husbandry. To man, the grassland plays a key role in living and development. But the grassland deterioration has alerted us. From 1989 to 1999, the deterioration area had increased by 4333 thousand hm2. The deterioration can cause the descent with grassland ecosystem productivity and net ecosystem productivity. Overgrazing and reclaiming cause the deterioration. So investigating the grassland resource is very important to guide husbandry animal and figure out macro-economy and development plan.Remote sensing shows its charming in investigating resources, monitoring environment and planning region etc. Many researchers have spent much time in grassland resource by using Landsat/MSS, Landsat/TM and NOAA/AVHRR. Based on the actual use-time and the practical yield, the carrying capacity measured is crucial. Yet the relevant literatures about using remote sensing to measure the grassland according to season were seldom.Aletai prefecture lies in the northern of the Xinjiang Uygur Autonomous Region. Aletai have 9842.4 thousand hm2 grassland area. 7239.3 thousands hm2 can be utilized directly. It is one of the important pastures in China and the central grassland animal husbandry bases in Xinjiang. As a simple stock raising district，the seasonal grazing is the traditional use means.MODIS’s time resolution is superior to TM’and SPOT’s. While its spatial resolution is bigger than NOAA/AVHRR’s. Since MODIS was launched in 1999，relevant MODIS literatures in grassland applications were short.The research utilized ERDAS IMAGINE software to process the MODIS datum in order to match the measured values. The correlation relationship between the normalized difference vegetation index from MODIS and the yield of grassland was regressed. The yield of the grassland and the classified output according to the classification rule were provided. With GIS, the carrying capacity of the summer, winter, spring and autumn pasture has been analysed.The main results of the research are as follows:(1) By collecting a long-time ARNDVI, every maximal value of pictorial element was abstracted. This can improve the accuracy.(2) The relationship of ARNDVI and the survey yield had been compared and the regression model was worked out according to seasonal pastures. Spring and autumn pasture：y1=137.8311+1.219613x 0≤x≤190y2=-90.3710+1.243571x 255≥x>190 R=0.857 Winter pasture：y1=57.31877+0.021251x 0≤x≤121　　　　　　　　　　　　　 y2=-579.465+5.148731x 255≥x>121 R=0.867　　　　　　　Summer pasture：y1=17.19495+0.411811x 0≤x≤148 <WP=7>　　　　　　　　　　　 y2=-23.9173+1.966378x 255≥x>148 R=0.807y—grassland yield ，x—ARNDVI number，R—Correlation expressed between y and x(3) The research showed that in the year 2002 the total area was 9640504.24hm2 in Aletai prefecture. According to the classification, the 3rd grade, 4th grade, 5th grade and 6th grade accounted for 3.46%、34.95%、13.14% and 33.26% respectively. The theoretical carrying capacity in 2002 was 6584005 sheep units. But the practical carrying capacity was 7887390 sheep units and so overload 48.38%. Summer pasture became the key pasture. So comply with the use from “summer pasture’s preponderance” add to spring and autumn pasture and winter pasture. Because of the limit time and so on, some further study as followed should be carried out.(1) The better vegetation index should be selected by thoroughly research about the correlation between vegetation index and the yield.(2) The stable regression model should be established. So more time should be spent to establish grassland ecological environment security measures index and monitoring warning system.(3) Overgrazing and the climate element are two kinds of viewpoint leading to grassland deterioration. Soil use and the soil cover alternation is a pressing task in the world environmental change research更多还原