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31.
This paper explores the links between economic growth and the impacts of climate change. Inclusive, pro-poor growth is central to the development of low-income countries. There is also a broad consensus that growth and development are important to reduce vulnerability to climate change. Growth does not automatically reduce vulnerability, only the right kind of growth does. The paper aims to develop a better understanding of what the ??right kind of growth?? may be. We find that many growth policies, such as investment in skills and access to finance, indeed reduce vulnerability to climate change. However, climate change calls for some adjustments in growth policy. In particular, investment in infrastructure and efforts to stimulate entrepreneurship and competitive markets must take more of a risk management perspective and recognise climate risks.  相似文献   
32.
在第二次全国土地调查县级农村土地调查现状资料成果的基础上,基于MapGIS K9软件,建设包括影像、图形、属性等的空间数据和集信息获取、处理、存储、传输、分析、应用服务为一体的市级土地利用数据库管理系统。  相似文献   
33.
Lei  Chao  Ren  Jianye  Pei  Jianxiang  Liu  Bowen  Zuo  Xiang  Liu  Jiaao  Zhu  Shiguo 《中国科学:地球科学(英文版)》2021,64(11):1893-1908
Science China Earth Sciences - The Red River Fault, which originated from the southeastern margin of the Tibetan Plateau, has a great significance for obtaining a further understanding of the...  相似文献   
34.
The Bonneville basin, located in north-western Utah, is a vast evaporite basin which is home to the world-renowned Bonneville Salt Flats international speedway and is a highly valued landscape undergoing rapid change and anthropogenic influence. Air quality, snowpack, the local hydrological system, and state tourism are all impacted by the nature of the surface sediments exposed in the Bonneville basin. Mapping the Bonneville basin over time with remote sensing methods provides insight into the dynamics and impacts of the changing surface landscape. Utilizing the Landsat-5 Thematic Mapper (TM) and Landsat-8 Operational Land Imager (OLI) sensors, a set of band math indices are empirically established to map the predominant halite, gypsum, and carbonates mineralogical zones of the Bonneville basin. Spectral comparisons of representative samples from the study area and image-derived spectra indicate the halite of the Bonneville basin is wet and that gypsum deposits are slightly mixed with halite. The established indices are assessed in four ways, all of which support the ability of the indices to accentuate the associated mineralogical endmembers. Two study areas within the Bonneville basin are investigated temporally from 1986, 1995, 2005, and 2016 and show changing patterns in mineral distribution that align with surface processes active through these timescales. These indices provide a resource for mapping mineralogy though time in evaporite basins globally with diverse applications for questions about land use and environmental change.  相似文献   
35.
在2015—2020年部分时段内,洛阳地震台水氡测值出现异常变化,利用水质和地球化学分析方法,对观测井、周边水井、伊河、龙门煤矿进行分析,认为水氡异常变化主要与台站更换水泵、大气降水、伊河水位变化以及附近龙门煤矿透水有关,排除地震异常,可为周边地区震情研判提供参考。  相似文献   
36.
Himalayan orogenic belt is the highest and largest continental collision and subduction zone on the Earth. The Himalayan orogenic belt has produced frequent large earthquakes and caused several geohazards due to landslides and housing collapse, having an impact on the safety of life and property along a length of over 2500 km. Here we took three earthquake clusters as examples, which occurred at Nepal Himalaya, eastern Himalayan syntaxis and western Himalayan syntaxis, respectively. Here we calculated the earthquake locations and fault plane solutions based on the waveform data recorded by seismic stations deployed in source areas by the Institute of Tibetan Plateau Research, Chinese Academy of Sciences. We found that at the Nepal Himalayan, the Main Himalayan Thrust is the major tectonic structure for large earthquakes to occur. At the eastern Himalayan syntaxis, most earthquakes are of the reverse or strike-slip faulting. The major tectonic feature is the combination of the NE-dipping thrust with the southeastern escape of the Tibetan plateau. At the western Himalayan syntaxis, intermediate-depth earthquakes are active. These observations reveal the geometry of the deep subduction of the continental plate with steep dipping angle.  相似文献   
37.
The Xiuwenghala gold deposit is located in the Beishan Orogen of the southern Central Asian Orogenic Belt. The vein/lenticular gold orebodies are controlled by Northeast‐trending faults and are hosted mainly in the brecciated/altered tuff and rhyolite porphyry of the Lower Carboniferous Baishan Formation. Metallic minerals include mainly pyrite and minor chalcopyrite, arsenopyrite, galena, and sphalerite, whilst nonmetallic minerals include quartz, chalcedony, sericite, chlorite, and calcite. Hydrothermal alterations consist of silicic, sericite, chlorite, and carbonate. Alteration/mineralization processes comprise three stages: pre‐ore silicic alteration (Stage I), syn‐ore quartz‐chalcedony‐polymetallic sulfide mineralization (Stage II), and post‐ore quartz‐calcite veining (Stage III). Fluid inclusions (FIs) in quartz and calcite are dominated by L‐type with minor V‐type and lack any daughter mineral‐bearing or CO2‐rich/‐bearing inclusions. From Stages I to III, the FIs homogenized at 240–260°C, 220–250°C, and 150–190°C, with corresponding salinities of 2.9–10.9, 3.2–11.1, and 2.9–11.9 wt.% NaCl eqv., respectively. The mineralization depth at Xiuwenghala is estimated to be relatively shallow (<1 km). FI results indicate that the ore‐forming fluids belong to a low to medium‐temperature, low‐salinity, and low‐density NaCl‐H2O system. The values decrease from Stage I to III (3.7‰, 1.7–2.4‰, and ?1.7 to 0.9‰, respectively), and a similar trend is found for their values (?104 to ?90‰, ?126 to ?86‰, and ?130 to ?106‰, respectively). This indicates that the fluid source gradually evolved from magmatic to meteoric. δ34S values of the hydrothermal pyrites (?3.0 to 0.0‰; avg. ?1.1‰) resemble those of typical magmatic/mantle‐derived sulfides. Pyrite Pb isotopic compositions (206Pb/204Pb = 18.409–18.767, 207Pb/204Pb = 15.600–15.715, 208Pb/204Pb = 38.173–38.654) are similar to those of the (sub)volcanic ore host, indicating that the origin of ore‐forming material was mainly the upper crustal (sub)volcanic rocks. Integrating evidence from geology, FIs, and H–O–S–Pb isotopes, we suggest that Xiuwenghala is best classified as a low‐sulfidation epithermal gold deposit.  相似文献   
38.
利用X射线衍射(XRD)技术对冲绳海槽南部HOBAB4-S2站700年以来的黏土矿物组成以及结晶学特征进行了研究和分析,并对该区的沉积特征、物质来源以及黏土矿物所记录的东亚季风的演化历史进行了探讨。研究发现冲绳海槽南部HOBAB4-S2站黏土矿物组合总体是以伊利石(59–77 %,平均含量69 %)和绿泥石(11–17 %,平均含量14 %)为主,而蒙脱石(5–23 %,平均含量12 %)和高岭石含量(2–6 %,平均含量4 %)则相对较低。通过黏土矿物研究对物源进行分析,发现冲绳海槽南部研究站位的黏土矿物中,蒙脱石主要是来自于长江或者东海大陆架的再沉积。伊利石,绿泥石以及高岭石主要来自于台湾河流,尤其是兰阳溪。蒙脱石/(伊利石+绿泥石)比值的大小可以用来指示东亚夏季风的强弱变化。1320 AD以来的黏土矿物组合的变化较好地记录了部分中世纪暖期后期、小冰期以及现代暖期3个时期在百年时间尺度上的气候波动。该指标显示,相对于中世纪暖期后期,东亚季风强度在小冰期(1405–1850 AD)和在现代暖期(1955 AD)均存在明显的减弱,指示该时期台湾东北部-冲绳海槽南部地区处于相对湿润强降雨的气候环境。  相似文献   
39.
使用空间无关的公平性衡量指数评价公交服务时,会忽视公交服务需求与供给的空间分布特征。为解决此问题,论文提出基于空间公平理论的公交服务评价框架,即通过构建综合基尼系数与莫兰指数的空间公平评价方法,实现整体尺度公交服务评价;通过对分析单元上相对需求与相对供给变量的匹配关系、空间差距进行分析,实现局部尺度公交服务评价,对整体尺度结果进行补充。深圳市的案例研究表明:① 基于平等主义的整体尺度空间公平指数显示,空间公平性最好与最差的行政区均位于中心城区,分别为罗湖区与南山区;② 局部尺度分析结果进一步印证,单一使用基尼系数评价公交服务存在局限性,相同或接近的基尼系数可以对应完全不同的公交服务不公平状态与供需匹配情况。  相似文献   
40.
选取中国沿海海洋站中与验潮室并址的22个GNSS基准站近9 a的观测资料,利用最大似然估计法分析各站时间序列的噪声特性,建立最优噪声模型;然后顾及有色噪声,利用最优噪声模型估计测站速度,并与纯白噪声模型和GLOBK获取的速度及误差进行对比分析。结果表明:1)沿海海洋站的GNSS时间序列均含有有色噪声,各分量的噪声特性不完全一致,E方向和U分量均以白噪声+闪烁噪声为主,N分量以白噪声+闪烁噪声和白噪声+一阶马尔科夫噪声+随机漫步噪声为主。2)全国沿海3个海区N、E分量的白噪声和闪烁噪声基本呈现越往南噪声越大的规律,南海海区U分量的白噪声和闪烁噪声最大。3)顾及有色噪声的速度中误差是仅考虑白噪声和GLOBK估计的速度中误差估计值的5~10倍,这种差异比内陆观测站的要大。4)在对海洋站GNSS时间序列进行速度分析时,为获取正确的速度值,应该先准确判断噪声的类型,再顾及有色噪声的影响估计测站速度。  相似文献   
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