KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY，CAS
| 基于 NDVI 时间序列的巴音布鲁克植被变化研究 | |
| 高庆 | |
| Subtype | 硕士 |
| Thesis Advisor | 艾里西尔·库尔班 |
| 2018-06-01 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 新疆乌鲁木齐 |
| Degree Discipline | 工程硕士 |
| Keyword | 巴音布鲁克 NDVI时间序列 生长季峰值 物候期 Bainbluk Prairie NDVI Time-series Peak of Growing Season Phenology |
| Abstract | 草地是一种重要的自然资源，是生态系统的重要组成部分，与森林一起构成我国陆地生态系统的主体。草地不仅是畜牧业发展的重要物质基础和牧区农牧民赖以生存的基本生产资料， 还是维护陆地生态系统的天然屏障。 草地对地球环境有着非常重要的作用， 尤其是在防风固沙、涵养水源、保持水土、净化空气以及维护生物多样性等方面。 近年来，由于受全球气候变暖等自然因素影响，加之人为开垦、超载过牧、 草原遭到十分严重的破坏， 草原覆盖度不断下降，生态持续恶化。巴音布鲁克草原是我国第二大草原和第一大高山草原，也是新疆最重要的牧场之一。由于其具有巨大的生态价值和经济价值，该区域草原植被的变化一直被广泛的关注。本文以 MODIS MOD09A1 为数据源，提取不同时期的 NDVI 数据组成 NDVI 时间序列，对 NDVI 时间序列进行去云和时间校正处理。用 Savitzky-Golay 滤波法对去云和时间校正后的 NDVI 时间序列进行重建，基于重建后的 NDVI 时间序列用动态阈值法提取植被的生长季开始时间、生长季峰值（生长季最大 NDVI 值） 和生长季结束时间，得到研究区生长季开始时间、生长季峰值和生长季结束时间的空间分布格局，变化趋势的空间分布以及各类植被的生长季开始时间、生长季峰值和生长季结束时间的年际变化。探索各类植被的生长季开始时间、生长季峰值和生长季结束时间与海拔之间的关系。结合气象因素，探索高山植被、 草原、草甸和沼泽的生长季开始时间、生长季峰值和生长季结束时间与气象因素（气温、降水）之间的关系。 得到的结论主要如下：（1）研究区植被生长季峰值（生长季 NDVI 最大值）介于 0.0065-0.8943 之间，植被主要集中在盆地及低海拔的山地区域。植被生长季开始时间主要介于 4 月中旬至5 月下旬，生长季结束时间主要介于 9 月上旬至 10 月中旬。 各类植被生长季峰值总体上随着海拔的升高而降低，草原、草甸和沼泽的生长季开始时间总体上随着海拔的升高而推迟，生长季结束时间总体上随着海拔的升高而提前，高山植被的生长季开始时间和结束时间基本不受海拔变化的影响；（2） 植被生长季峰值在研究区南方以增加为主，在研究区北方以减少为主。生长季开始时间以提前为主， 生长季结束时间在研究区以南主要呈推迟趋势， 在研究区以北主要呈提前趋势。 高山植被、草原和草甸的生长季峰值总体无明显变化，沼泽有微小的增加趋势。草原、草甸和沼泽的生长季开始时间总体上呈提前趋势，高山植被的生长季开始时间总体上呈微小的提前趋势。各类植被的生长季结束时间总体上呈提前趋势，高山植被和草原提前趋势显著，草甸和沼泽提前趋势不显著。（3）研究区植被的生长季开始时间主要受春季温度和前一年 11 月份的降水影响，其中高山植被主要受 5 月的温度影响，草原和沼泽主要受 4 月份的温度影响，草甸主要受 4 月份和 5 月份的温度影响，春季温度的升高和前一年 11 月份降水的增加会使植被的生长季开始时间提前。各植被生长季结束时间受气象因素差异较大，高山植被和草甸主要受 5 月、 6 月、 8 月气温和 9 月降水的影响， 5 月和 6 月的气温升高使生长季结束时间提前， 8 月气温升高使生长季结束时间推迟， 9 月的降水增加使生长季结束时间提前。草原和草甸的生长季结束时间主要受 10 月降水的影响， 10 月降水的增加会使草原和草甸的生长季结束时间提前。 |
| Other Abstract | Grassland is the largest ecological green-shelter in China, and together with forestsconstitute the main body of China's terrestrial ecosystem. The grassland is not only theimportant material base of animal husbandry development, but also the basic productiondata of the farmers and herdsmen in pastoral areas, and the natural barrier to maintain theterrestrial ecosystem. As the “skin” of the earth, grassland plays a very important role inwindbreak and sand fixation, water resource conservation, conserving water and soil,purifying air, and maintaining biodiversity. In the long term, due to the natural factors suchas global warming, as well as the cultivation of grasslands, overgrazing and the destructionof grassland vegetation, the grassland degradation and ecological deterioration have beenworsening.The Bainbluk prairie is the second largest grassland in China and one of the mostimportant pastures in Xinjiang. Because of its great ecological value and economic value,the change of grassland vegetation in this region has been widely concerned. In this paper,MODIS MOD09A1 is used as the data source to extract NDVI data from different periodsto compose the NDVI time series, and the NDVI time series is subjected to cloud removaland time correction. The Savitzky-Golay filter method was used to reconstruct the NDVItime series after cloud removal and time correction. Based on the reconstructed NDVI timeseries, the dynamic threshold method was used to extract the start time of the growingseason and the peak of the growing season (the maximum NDVI value of the growingseason). At the end of the growing season, the spatial distribution pattern of the start timeof the growing season, the peak of the growing season, and the end of the growing seasonare obtained. The spatial distribution of the changing trend and the start time of thegrowing season, the peak of the growing season and the end of the growing season for alltypes of vegetation Interannual variability. Explore the relationship between the start timeof the growing season, the peak of the growing season, and the end of the growing seasonwith altitude. Combining meteorological factors, the relationship between the start time ofthe growing season, the peak of the growing season and the end of the growing season, andthe meteorological factors (temperature and precipitation) of alpine vegetation, grasslands,meadows and swamps were explored. The main conclusions are as follows:（1） The peak value of vegetation growth season in the study area (maximum NDVIin the growing season) ranges from 0.0065 to 0.8943. Vegetation is mainly concentrated inbasins and low altitude mountainous regions. The beginning of vegetation growth season ismainly from mid-April to late May. The end of the growing season is mainly from earlySeptember to mid-October. In the flat basin area and the low-altitude mountainous area,the start time of the vegetation growth season and the end of the growing season are mainlyaffected by vegetation types. In the higher altitude areas, the start time of the vegetationgrowth season and the end of the growing season are mainly affected by the elevation.With the increase of altitude, the peak value of all vegetation growth seasons in the studyarea generally decreases with the increase of altitude. The start time of the growing seasonis postponed with the elevation, and the end of the growing season increases with theelevation.（2） The peak of vegetation growth season is mainly increasing in the south of thestudy area, and mainly decreasing in the north of the study area. The beginning of thegrowing season was mainly in advance. The ending of the growing season was mainlydelayed in the south of the study area and was advanced in the north of the study area.There was no significant change in the peak season of alpine vegetation, grassland andmeadow in the study area, and there was a slight increase in the swamp. The onset time ofthe growing season in grasslands, meadows and swamps generally showed an early trend,and the start time of the growing season of alpine vegetation showed a slight extractiontrend overall. The end of the growing season of all types of vegetation in the study areashowed an overall advancement trend. The advancement trend of alpine vegetation andgrassland was significant, and the trend of meadow and swamp advance was notsignificant.（3） The start time of the growing season of vegetation in the study area is mainlyaffected by the spring temperature and the precipitation in November of the previous year.The alpine vegetation is mainly affected by the temperature in May. The grasslands andswamps are mainly affected by the temperature in April. The meadow is mainly affectedby the effects of temperature in April and May, the increase in temperature in spring andthe increase in precipitation in November of the previous year will advance the start of thegrowing season of vegetation. The end of the vegetation growing season is affected bymeteorological factors. The alpine vegetation and meadows are mainly affected by thetemperatures in May, June and August and the precipitation in September. The rising temperatures in May and June make the end of the growing season. In advance, theincrease in temperature in August delayed the end of the growing season, and the increasein precipitation in September advanced the end of the growing season. The end of thegrowing season in grasslands and meadows is mainly affected by precipitation in October.The increase in precipitation in October will advance the end of the growing season ingrasslands and meadows. |
| Subject Area | 测绘工程 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xjlas.org/handle/365004/14964 |
| Collection | 研究系统_荒漠环境研究室 |
| Affiliation | 中国科学院新疆生态与地理研究所 |
| First Author Affilication | 中国科学院新疆生态与地理研究所 |
| Recommended Citation GB/T 7714 | 高庆. 基于 NDVI 时间序列的巴音布鲁克植被变化研究[D]. 新疆乌鲁木齐. 中国科学院大学,2018. |
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