Knowledge Resource Center for Ecological Environment in Arid Area
| 基于遥感降水的青藏高原干湿状况研究（2001-2010年） | |
| 其他题名 | Dry-wet pattern of the Qinghai-Tibetan Plateau based on precipitation derived from Remote Sensing(2001-2010) |
| 王敏 | |
| 出版年 | 2012 |
| 学位类型 | 硕士 |
| 导师 | 周才平 |
| 学位授予单位 | 中国科学院大学 |
| 中文摘要 | 作为全球变化的特征之一，区域干湿气候变化已成为全球变化研究的重要内容，其对生态系统的影响也已成为当今全球面临的最重要的环境问题之一。青藏高原是全球变化的敏感区和脆弱区，也是我国乃至全球气候系统稳定的重要屏障，但在全球变化和人类活动的共同影响下，高原生态环境问题日趋凸显，生态安全屏障功能受到威胁。植被是陆地生态系统中最重要的、同时也是气候变化最敏感的组分，而高原植被系统行为往往比其他地区能更早、更明显地预兆全球变化。探讨青藏高原区域干湿状况及其与植被变化的关系有助于更好地认识和理解陆地生态系统对气候变化的响应和适应机理，对高原生态安全屏障计划的实施以及全球生态建设有重要意义。\n本文分别采用遥感估算降水模型（RFE 2.0）和彭曼模型（Penman-Monteith）估算了2001-2010年青藏高原生长季降水和潜在蒸散，基于干燥度指数分析了高原近10年生长季干湿状况的时空变化及其驱动性因素，并对高原区域干湿状况与植被变化的关系进行了探讨。主要结论如下：\n（1） 2001-2010年青藏高原生长季（5-9月）平均温度为7.2℃，降水量为374mm，潜在蒸散为697mm。10年来，高原绝大部分区域生长季平均温度表现为增加趋势，平均增幅为0.24℃，其中高原西北部等区域增幅达0.4℃；高原生长季降水总体上呈现南部降水减少、北部降水增加趋势，平均增幅达13mm；高原东北部生长季潜在蒸散呈下降趋势，其他区域表现出不同程度的增加趋势，平均增幅为3mm。\n（2）整个高原有67%的区域属于干旱和半干旱区，降水是导致青藏高原干湿状况空间格局差异的主要因素，气候变化对高原干旱区和半干旱区的影响最大。近10年高原有25%的区域在逐渐变干，主要集中在高原南部，特别是高原腹地、柴达木盆地、青海湖、西藏东部及甘孜州南部等区域变干趋势最为明显。高原总体上表现为北部干旱程度在逐渐减轻，南部干旱化趋势明显。高原大部分区域干湿状况对潜在蒸散的变化最为敏感，但高原半湿润到半干旱过渡区域则对降水变化最为敏感。\n（3）高原生长季EVI呈现自东南向西北逐渐递减的趋势，且东西部界线分明。高原东部及东南部EVI主要在0.20~0.40之间，高原西部及北部EVI主要在0.02~0.15之间；十年间高原有25%的区域植被呈退化趋势，48%的区域植被活动表现为增强趋势。整体上来看，高原植被活动由东南向西北整体上呈现“退化-增强-变化不大”的规律。高原不同尺度生长季干燥度指数与EVI的相关性均达到显著水平（相关系数在0.37以上）。人为干扰对高原EVI变化的作用不明显，但EVI与干旱指数相关性相对偏小的区域人为干扰程度往往较大。区域干湿气候变化是决定高原生长季植被覆盖变化的主要因素。青藏高原96个气象站点生长季EVI对干燥度指数变化的敏感程度较大的区域主要集中在高原东北部、高原中部及雅鲁藏布江中上游区域。 |
| 英文摘要 | As one of the striking characteristics of global change, regional dry-wet climate variations and its effects on ecosystems has become one of the most important environment problems being faced by the world, and has been the focus and the advancing edge of global change study. Qinghai-Tibetan Plateau (QTP) is both a climate change frontier and natural defense of stable climate system of China and around the world. However, impacted by the global warming and anthropogenic activities, the ecological environment problems show up gradually, and the ecological shelter zone is seriously threatened. Vegetation is the most important and the most sensitive composition of climate change, and compared to other regions, the action of the vegetation system can have earlier and more obvious indicating effects of global change. The study of regional dry-wet status of the QTP and its relation to the vegetation changes will improve our understanding of the response and adaptation mechanisms of terrestrial ecosystems to climatic change, and also will have very important implications to the implementation of the scheme of ecological shelter zone and contribute to global ecosystem management activities.\nIn this study, the model of RFE 2.0 and Penman-Monteith were used to estimate the precipitation and potential evapotranspiration of the QTP in growth season of the last ten years, respectively. Then based on the aridity index derived from the precipitation and potential evapotranspiration, the temporal and spatial character and driving forces of dry-wet condition of the QTP in the growth season of this period were analyzed. Finally, the relationship between variations of regional dry-wet climate and vegetation change were explored and discussed.\n（1）Mean tempreture, precipitation and potential evapotranspiration of growing season(May-Sep) during 2001-2010 on the Qinghai-Tibetan Plateau was 7.2℃, 374mm, 697mm, respectively. In the last decade, mean temperatures of most area showed increased tendency, the average gain was 0.24℃, and the northwest plateau even got 0.4℃. Precipitation presented overall trend of decrease in the south and increase in the north, the average gain was 13mm. As for the potential evapotranspiration, the northeast plateau showed a decline trend, and the other areas showed various degree of increased trends, the average gain was 3mm.\n（2）Around 67% of the area on the QTP belongs to the arid and semi-arid climate zone. Precipitation was the major factor that brings to the variations of dry-wet pattern on the plateau, and the most affected by global climate change happened in arid and semiarid areas. From 2001 to 2010, 25% of the plateau exhibits drought trend, mainly in southern plateau, especially in mid part of Tibetan highland, Qaidam Basin, Qinghai Lake, eastern Tibet and southern Ganzi District, the drying trend were of most obvious. For all, in the last decade, drought condition of the northern QTP that belong to the arid and semi-arid areas has reduced gradually, but the south and southeast of the plateau were getting drought. The sensibility of drought index to the change of potential evapotranspiration in most of the plateau area was the biggest, and the drought trend of the QTP was due to the comprehensive effect of both precipitation and potential evapotranspiration.\n（3）The spatial pattern of enhanced vegetation index (EVI) during the growing season were similar to that of drought, showing clearly defined boundaries between the western and eastern parts. The range of EVI in eastern and south-eastern plateau was between 0.20~0.40, and in northern and western plateau was between 0.02~0.15. During the last 10 years, about 25% of the area presented obvious vegetation degradation. On the whole, the activities of plateau vegetation were showing the pattern of “degenerate- strengthen-little change” from the southeast to the northwest.The correlation between the drought index and EVI at different scales of QTP were all significant (with the correlation coefficients above 0.37). The effects of anthropogenic activities on the vegetation distribution were not very significant, but there was a relatively weak relationship between drought index and EVI in the area with intensive human interferences. Variations of regional dry-wet climate were the main components of the change of vegetation cover. The higher sensibility of EVI to drought index of 96 meteorological sites during the growing seasons was distributed mainly in northeast and central plateau, and also along the upstream of Brahmaputra River. |
| 中文关键词 | 青藏高原 ; 降水 ; 潜在蒸散 ; 干湿状况 ; 植被 |
| 英文关键词 | Qinghai-Tibet Plateau precipitation potential evapotranspiration dry-wet condition Vegetation |
| 语种 | 中文 |
| 国家 | 中国 |
| 来源学科分类 | 生态学 |
| 来源机构 | 中国科学院地理科学与资源研究所 |
| 资源类型 | 学位论文 |
| 条目标识符 | http://119.78.100.177/qdio/handle/2XILL650/287055 |
| 推荐引用方式 GB/T 7714 | 王敏. 基于遥感降水的青藏高原干湿状况研究（2001-2010年）[D]. 中国科学院大学,2012. |
| 条目包含的文件 | 条目无相关文件。 | |||||
| 个性服务 |
| 推荐该条目 |
| 保存到收藏夹 |
| 导出为Endnote文件 |
| 谷歌学术 |
| 谷歌学术中相似的文章 |
| [王敏]的文章 |
| 百度学术 |
| 百度学术中相似的文章 |
| [王敏]的文章 |
| 必应学术 |
| 必应学术中相似的文章 |
| [王敏]的文章 |
| 相关权益政策 |
| 暂无数据 |
| 收藏/分享 |
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。
