排序方式： 共有34条查询结果，搜索用时 7 毫秒
31.
祁连山冰川服务价值评估及其时空特征 总被引：1，自引：0，他引：1
冰川为干旱区人类福祉和社会经济发展提供必不可少的资源与服务,开展冰川服务价值评估及时空特征研究对于区域社会经济可持续发展和环境保护具有重要意义。基于祁连山第一次和第二次冰川编目数据,通过构建冰川服务价值评估体系,并结合单位面积服务价格法、价值当量因子法和冰川服务价值变化指数等方法,评估祁连山冰川服务价值及时空变化。结果表明：① 2016年祁连山冰川服务价值为243.54亿元,气候调节和径流调节构成该地区冰川最主要的服务,其次是淡水资源供给和水力发电,四者分别占总价值的60.58%、33.14%、3.47%和1.75%,其他类型服务价值约为2.59亿元。② 在祁连山各水系中,疏勒河流域冰川服务价值最高（77.71亿元,占31.91%）,其次为哈尔腾河流域（43.21亿元,占17.74%）和北大河流域（32.81亿元,占13.47%）。在行政区划上,青海省的祁连山冰川服务价值高于甘肃省11.38亿元,其中海西蒙古族藏族自治州和酒泉市境内的冰川服务价值较高,分别为111.24亿元（占45.68%）和77.58亿元（占31.86%）。③ 1956—2010年期间,祁连山冰川服务价值量损失4.35亿元,且冰川服务价值变化呈现经向地带性分异规律,价值损失自西向东呈加快趋势。 相似文献
32.
After the bursting of Huiten Nor in Hoh Xil Region in September, 2011, the topic on whether the water overflowed from the Salt Lake would enter into the Chumaer River and become the northernmost source of the Yangtze River has aroused wide concern from public and academic field. Based on Landsat TM/ETM+/OLI remote sensing images during 2010–2015, SRTM 1 arc-second data, Google Earth elevation data and the observation data from the Wudaoliang meteorological station, the study initially analyzed the variations of the Salt Lake and its overflowing condition and probability. The results showed that the area of the Salt Lake expanded sharply from October 2011 to April 2013, and then it stepped into a stable expansion period. On October 27, 2015, the area of the Salt Lake had arrived at 151.38 km~2, which was about 3.35 times the area of the lake on March 3, 2010. The Salt Lake will overflow when its area reaches the range from 218.90 km~2 to 220.63 km~2. Due to the differences between SRTM DEM and Google Earth elevation data, the water level of the Salt Lake simulated would be 12 m or 9.6 m higher than the current level when the lake overflowed, and its reservoir capacity would increase by 23.71 km~3 or 17.27 km~3, respectively. Meanwhile, the overflowed water of the Salt Lake would run into the Qingshui River basin from its eastern part. Although the Salt Lake does not overflow in the coming decade, with watershed expansion of the Salt Lake and the projected precipitation increase in Hoh Xil region, the probability of water overflow from the Salt Lake and becoming a tributary of the Yangtze River will exist in the long term. 相似文献
33.
As one of the areas with numerous lakes on the Tibetan Plateau, the Hoh Xil region plays an extremely important role in the fragile plateau eco-environment. Based on topographic maps in the 1970 s and Landsat TM/ETM+ remote sensing images in the 1990 s and the period from 2000 to 2011, the data of 83 lakes with an area above 10 km2 each were obtained by digitization method and artificial visual interpretation technology, and the causes for lake variations were also analyzed. Some conclusions can be drawn as follows.(1) From the 1970 s to 2011, the lakes in the Hoh Xil region firstly shrank and then expanded. In particular, the area of lakes generally decreased during the 1970s–1990s. Then the lakes expanded from the 1990 s to 2000 and the area was slightly higher than that in the 1970 s. The area of lakes dramatically increased after 2000.(2) From 2000 to 2011, the lakes with different area ranks in the Hoh Xil region showed an overall expansion trend. Meanwhile, some regional differences were also discovered. Most of the lakes expanded and were widely distributed in the northern, central and western parts of the region. Some lakes were merged together or overflowed due to their rapid expansion. A small number of lakes with the trend of area decrease or strong fluctuation were scattered in the central and southern parts of the study area. And their variations were related to their own supply conditions or hydraulic connection with the downstream lakes or rivers.(3) The increase in precipitation was the dominant factor resulting in the expansion of lakes in the Hoh Xil region. The secondary factor was the increase in meltwater from glaciers and frozen soil due to climate warming. 相似文献
34.
Based on the radiosonde data observed at 14 stations in Southwest China from 1960 to 2010, as well as the corresponding surface air temperature, the long-term change of free-air 0 ℃isotherm height in Southwest China and the relationships between surface air temperature and 0 ℃isotherm height are discussed. The results indicated that the spatial distribution of 0 isotherm height is generally related with latitude, but the ℃ huge massif or plateau may complicate the latitude pattern. The two main regimes influencing the spatial patterns of 0 isotherm height℃ in Southwest China are latitude and huge massif. The annual 0 isotherm height has increased by 35 m per decade in the recent decades, which is st℃ atistically significant at the 0.001 level. Generally, the increasing trend can be examined for each seasonal series, especially in winter(53 m per decade). The diversity of trend magnitudes for annual and seasonal series can also be detected at a spatial view, but generally 0 ℃isotherm height correlated well with surface air temperature. 相似文献