【作者】 孟翔冲；

【导师】 姜琦刚；

【作者基本信息】 吉林大学 ， 地球探测与信息技术， 2012， 硕士

【摘要】 土地荒漠化作为威胁人类生存和发展的十大环境问题之一，具有区域尺度与全球尺度的环境效应，是全球变化研究中一项重要的研究内容，其造成的环境恶化和经济贫困是制约全球经济发展和影响社会稳定的重要因素。荒漠化不仅会对当地生态环境造成破坏，甚至会对远离数千公里的地区产生影响。蒙古国是世界上第二大内陆国家，其90%的土地位于干旱、半干旱气候带，是亚洲荒漠化现象最严重的国家之一。而中国北方农牧交错带是我国沙质荒漠化土地分布面积最广、程度最高的地区，与蒙古国戈壁荒漠区相接壤，其发生、发展与治理都有着相互的联系。我国的“三北”防护林工程、退耕还林还草等环境保护措施逐渐显现成效，北方沙尘天气的逐年减少，荒漠化土地面积的减少都离不开人民的努力。虽然我国荒漠化现象逐渐好转，但与我国相邻的蒙古国荒漠化现状如何，是否对我国产生影响是我们未来要考虑的问题，因此本研究探讨了蒙古国沙质荒漠化对我国北方荒漠化的影响关系。本文以1990年的TM数据、2000年的ETM数据以及2007年的CBERS数据为主要的影像数据源，通过人机交互解译的方式提取蒙古国荒漠化信息，并根据解译数据掌握沙质荒漠化在蒙古国的分布情况，同时运用GIS手段对蒙古国沙质荒漠化的时空动态变化、转移矩阵、动态度、变化强度等进行分析，并结合我国北方农牧交错带沙质荒漠化的三期解译数据变化情况、当地的沙尘暴天气分布规律以及气候地形等要素来探明境外荒漠化对我国荒漠化影响的重要性。通过研究本文得到以下结论：1、蒙古国沙质荒漠化主要分布在除蒙古国北部山区外的广袤戈壁及基岩山区低洼地带，由西向东呈弧形分布，多以重度的沙漠化类型为主。其总体面积由1990年的76080.13km~2减少到2000年的75951.68km~2，随后又增加到2007年的79587.45km~2总体上呈恶化趋势。2、通过对蒙古国沙质荒漠化土地类型的动态度计算可以看出，轻度、中度、极重度类型的沙质荒漠化均为加剧恶化，其中极重度由于分布面积少仅占总面积的4.78%，是变化速度最快的，而占沙化土地42.05%的重度沙化土地虽然逐年增加，但已经出现增加减缓的态势。但蒙古国内泥漠的面积迅速增加，为当地环境敲响警钟。3、通过转移矩阵的分析，大部分的荒漠化面积是稳定的，以重度沙化最为稳定，轻度和中度沙化与潜在沙化土地转化较为显著，1990年到2000年间，虽然总体上荒漠化面积有所减少，但通过转移矩阵可以看出，类型间转化上荒漠化土地仍向恶化加强发展。在2000年到2007年虽然面积有所增加，但在程度上有减弱的趋势。4、在蒙古国沙化变化强度上来看，主要集中在蒙古国南部戈壁荒漠地带及东南部戈壁区，其变化强度区与沙尘暴活跃区相一致。5、对蒙古国沙化重心迁移变化可知，除重度沙化重心外，沙化类型重心主要分布在蒙古国南部隔壁区域。总体上蒙古国沙质荒漠化的重心是向内陆回退的，这说明蒙古国内陆荒漠化有所加剧。6、我国北方农牧交错带沙质荒漠化主要分布研究区4个沙漠区的边缘地带以及6个沙地区域。荒漠化面积由1975年的245882.96km~2，增加至2000年的270419.82km~2，随后经过治理荒漠化面积约为2007年的240853.25km~2。荒漠化呈现好转的态势。7、每年春季都是我国北方沙尘天气高发的季节，这些沙尘天气绝大多数是由蒙古气旋所控制，分两路夹带着蒙古国的沙土进入我国。一路在蒙古国东南部起沙，影响我国华北大部分地区，另一路在蒙古国西部及南部戈壁荒漠起沙，影响我国西北华北地区。8、蒙古国荒漠化的分布走势主要受地形控制，呈西北向东南发展，同时与沙尘暴的路径相一致，尤其蒙古国中、南部地区是我国沙尘天气的主要境外沙源地，常年通过大风天气向我国输送沙土。而研究区荒漠化的变化及沙尘天气的变化都与该地区年降雨有着负相关关系，而温度则关系不大。人为治理是我国北方沙质荒漠化减少的主要因素，可见蒙古国荒漠化对我国北方荒漠化是有影响的，但远不及治理的影响强，但仍需要我们去加强境外环境的改善，这样我国的区域生态环境才会有所改善。更多还原

【Abstract】 As one of the ten major environmental problems that threaten the survival anddevelopment of human beings, land desertification can have regional-scale andglobal-scale environmental effects; it is among the important issues of the research onglobal environmental changes. The environmental deterioration as well as theeconomic poverty that caused by this problem have become the important factors thatrestrict the global economic development and affect social stability. Desertificationmay not only cause the destruction of the local ecological environment but also havean impact on the regions thousands of miles away.Mongolia is the second biggest inland country and nearly90%of its land islocated in the arid and semiarid climatic zone; in addition, it is also one of the nationsthat suffer the severest desertification in Asia. The farming-pastoral eco-tone innorthern China----the region that has the land desertification at the highest level withthe most extensive land distribution, borders upon the region of Gobi desert.Consequently, the occurrence, development and treatment of the desertification therehave a close connection with those in Gobi desert in Mongolia. The protectivemeasures such as building the Sanbei shelter-forest project and returning land forfarming to forestry or grassland appear to be effective. Moreover, the sand-dustweather in the north is decreasing year by year and the area of land suffering from thedesertification also diminishes. None of these can be achieved without the endeavor ofChinese people. Although the desertification of our country is looking up gradually,the present situation of Mongolia adjacent to us as well as whether it may bring someinfluences on our country are the issues worth taking into consideration. Thus, thispaper studies and discusses the influence of the sandy desertification in Mongolia onthe one in the Northeast China.This paper, based on the RS and GIS technology, takes the TM, ETM togetherwith CBERS data as the data source of the images. It extracts the information of thedesertification of Mongolia via the man-machine interactive interpretation so that the author can obtain the distribution of the sandy desertification in Mongolia accordingto the data got from the interpretation. In the meantime, by using the methodsgrounded on GIS, this paper conducts the analysis of the spatial-temporal dynamicchange, transfer matrix, dynamic degree as well as the intensity of change of thesandy desertification in Mongolia. After getting the data from the interpretation ofthree periods focused on the desertification of the farming-pastoral eco-tone innorthern China, the author can get the situation of the changes of the data. Connect itwith the distribution rule of the local sand-dust weather, the climate, the terrain andother factors the importance of the influence of the desertification outside Chineseborders on the one of our nation can be explored.The major findings are as follows:1. The sandy desertification in Mongolia is mainly distributed in the Gobi desertand the low-lying areas in the bedrock mountain area except the mountain district inthe north of the country. It is distributed in the shape of an acre from west to east, withmost part being severe desertification. The total area of the desertification reducedfrom76080.13km~2(1990) to75951.68km~2(2000), while increased to79587.45km~2(2007). On the whole, it is getting worse and worse.2. According to the calculation of the dynamic degree of type of the sandydesertification in Mongolia, the mild, moderate and severest types of sandydesertification are all deteriorating dramatically. The severest type only occupies4.78of the total area but is increasing most rapidly. With the proportion being nearly42.05%, the severe type increased on the whole, it has the tendency of increasingslower and slower. The area of argillaceous desert in Mongolia is increasing rapidlyand rings the alarm for the local people.3. Through the transition matrix, we can see that most of the area ofdesertification is stable especially for the severe type, with the mild type, moderatetype and potential type being obvious. Although the area of desertification diminishedduring the period from1990to2000on the whole, when observing the transitionmatrix, we can find that the phenomenon developed to be worse in terms of thetransformation among the types. Though the area enlarged from2000to2007, itbecame mild in terms of degree.4. When observing the intensity of changes, they mainly occur in the region ofthe Gobi desert that is located in the south and the southeast of Mongolia. The regionof the intensity of change is in accord with the active region of the sand storm.5. Learning from the changes of the focus migration, the center of gravity of the types of desertification is mainly distributed in the area of the region of Gobi desertsouth of Mongolia, with the center of gravity of the severe type being exceptional.Generally speaking, the center of gravity of the sandy desertification in Mongoliareceded to the inland areas which show the deterioration of the desertification.6. The sandy desertification of the farming-pastoral eco-zone in northern Chinamainly locates in the edge of four desert regions as well as6sandy regions. The areaof desertification ranges from245.882.96km~2in1975to270419.82km~2in2000. Aftersome control methods being taken, the area is nearly240853.25km~2. The phenomenonof desertification is looking up gradually.7. Spring is the season where dust weather strikes frequently in north China. Themajority of the sand and dust storms are controlled by Mongolia cyclone and carriesthe sand in Mongolia to our nation in two routes. One starts from the northwest ofMongolia which affects most regions of the north of China while another starts fromthe Gobi desert in the west and south of Mongolia and influence the north as well asthe northwest of China.8. The distribution of desertification of Mongolia is mainly controlled andinfluenced by terrain, showing a tendency of developing from the northwest tosoutheast. At the same time, it is in accordance with the route of the sand storm. Thesouthern regions together with thecentral ones are the main sources of the sand of foreign countries and transmit sand toour nation via strong winds. Changes of desertification in the studied area and thechanges of the sand-dust weather have negative impact on the annual rainfall in theregion, while the temperature has little to do with them. The main factor that thereduction of the sandy desertification in the north of China attributes to may be thehuman governance. We can conclude that the desertification in Mongolia hasinfluence on the desertification of the Northeast China, while such influence is weakerthan the influence of governance. It still needs us to intensify the improvement of theenvironment outside Chinese borders so that the climate of the regions of our nationcan be improved.更多还原