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Response of remotely sensed Normalized Difference Water Deviation Index to the 2006 Drought of eastern Sichuan Basin

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Science china Earth sciences 2008年第5期51卷 748-758页

作者： ZHANG WenJiang1, LU QiFeng2, GAO ZhiQiang3 & PENG Jian4 1 School of Water Resource and Hydropower, Sichuan University, Chengdu 610065, china 2 National Satellite Meteorological center, china Meteorological Administration, beijing 100081, china 3 Institute of Geographic sciences and Natural resources research, chinese academy of sciences, beijing 100101, china 4 School of Environmental sciences, Peking University, beijing 100871, china School of Water Resource and Hydropower Sichuan University Chengdu China National Statellite Meteorological center China Meteorological Administration Beijing China Institute of Geographic sciences and Natural resources research Chinese Academy of Sciences Beijing China School of Environmental sciences Peking University Beijing China

One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2006 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2001―2006 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2006 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently.

关键词： Sichuan Basin drought Normalized Difference Water Deviation Index response of remote sensing regional scale

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Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai

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Science china Earth sciences 2005年第7期48卷 939-949页

作者： SHAO Xuemei1, HUANG Lei1, LIU Hongbin2, LIANG Eryuan1, FANG Xiuqi3 & WANG Lili1 1. Institute of Geographic sciences and Natural resources research, chinese academy of sciences, beijing 100101, china 2. National Climate center, beijing 100081, china 3. beijing Normal University, beijing 100875, china Institute of Geographic sciences Natural Resources Research Chinese Academy of Sciences Beijing 100101 China National Climate center Beijing 100081 China beijing Normal University Beijing 100875 China

Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD1520—1633 and 1933—2001, whereas dry intervals in 1429—1519 and 1634—1741. In ad- dition, the magnitude in precipitation variation was lower before 1430 with about 15 mm, but it increased to 30 mm during the period of 1430 to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 21st century.

关键词： northeastern part of the Qaidam Basin tree-ring width series of Qilian juniper precipitation reconstruction in 1000 years.

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Carbon isotopic variations of Proterozoic carbonates in Jixian, Tianjin, china

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Science china Earth sciences 2004年第2期47卷 160-170页

作者： CHU Xuelei, ZHANG Tonggang, ZHANG Qirui, FENG Lianjun & ZHANG Fusong1. Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 2. Key Laboratory for mineral resources research, chinese academy of sciences, beijing 100029, china Correspondence should be addressed to Chu Xuelei (email: xlchu@***) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Key Laboratory for mineral resources research Chinese Academy of Sciences Beijing China

Along the Proterozoic stratigraphic sections of Jixian, Tianjin, the ??13C values of carbonates are mostly negative in the Changchengian (Changcheng System), varying approximately within a range of (0±1)‰ in the Jixianian (Jixian System), and have commonly positive values of (2±2)‰ in the Qingbaikouan (Qingbaikou System). From Chuanlinggou Formation to Dahongyu Formation, i.e. from ca. 1700 Ma to 1600 Ma, the δ13C values of carbonates increase from about -3‰ to 0‰, but oscillate with large excursion in Dahongyu Formation. Two large excursions occur in the Jixianian, one in Yangzhuang Formation and the other in the third submember of Wumishan Formation overlaying. These integrated and continuous records of carbon isotope reflect secular variations of δ13C value in ancient seawater from ca. 1700 Ma to ca. 800 Ma. The increase and subsequent oscillation of seawater δ13C value occurring from the ages of ca. 1700 to ca. 1600 Ma and ＜1300 Ma may signify two correlative global tectonic events.

关键词： Proterozoic, Jixian, carbon isotope, chemostratigraphy, secular variation, global tectonic event.

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research on the multi-level intake water temperature effect of the Yalong River Jinping-I hydropower project

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Science china(Technological sciences) 2011年第S1期54卷 125-132页

作者： WU ShiYong 1,CAO Wei 1,WANG HongMei 1,SUN ShuangKe 2 &CHEN QiuWen 3 1 Ertan Hydropower Development Company,Ltd.,Chengdu 610051,china 2 china Institute of Water resources and Hydropower research,beijing 100038,china 3 research center for Eco-Environmental sciences,chinese academy of sciences,beijing 100085,china Ertan Hydropower Development Company Ltd.

Based on the discussion of the multi-level intake application status of high dam reservoir,this paper takes the Jinping-I hydropower project reservoir in the Yalong River as an example,which is shaped by the highest 305 m high arch dam,and carries out the forecasting research on the reservoir temperature by numerical simulation and physical model *** paper studies the intake effect of withdrawing the surface warm water by the stoplog gates inlets and verifies the reliability of the mathematical model by comparative *** results show that for a high dam hydropower station,taking the appropriate multi-level intake measure can withdraw the surface warm water in the spawning season and provide a favorable environment for the fish *** technical ideas and implementation scheme are adopted in this *** can provide technical reference for the solutions of similar problems in the future and it also has important engineering significance on the research of water temperature in large deep reservoirs.

关键词： water temperature multi-level intake Jinping-I hydropower project

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Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu mineralization

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Science china Earth sciences 2004年第3期47卷 221-231页

作者： HOU Zengqian1, QU Xiaoming1, WANG Shuxian2, DU Andao2, GAO Yongfeng3 & HUANG Wei4 1. Institute of mineral resources, chinese academy of Geological sciences, beijing 100037, china 2. National center of Geoanalysis, chinese academy of Geological sciences, beijing 100037, china 3. Shijiazhuang College of Economy, Shijiazhuang 056000, china 4. Xizang Bureau of Geology and mineral resources, Lhasa 850000, china Institute of mineral resources Chinese Academy of Geological Sci. Beijing 100037 China National center of Geoanalysis Chinese Academy of Geological Sci. Beijing 100037 China Shijiazhuang College of Economy Shijiazhuang 056000 China Xizang Bureau of Geol./mineral Rsrc. Lhasa 850000 China

The Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. The belt trends 350 km long along the EW-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the SN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 10 Ma to 18 Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (10—15 Ma) and mafic dykes (13—18 Ma). The timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 187Re-187Os isochron with a highly pre-cise age of (14.76?.22) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (14.04?.16) Ma. Re-Os model ages for two molybdenite samples from Lakang抏 deposit vary from 13.5 Ma to 13.6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.99719 and an isochron age of (14.39?.22) Ma (1s error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. The emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 21—23 Ma, and formed in a post-collision crustal ex-tension env

关键词： porphyry copper deposit, Re-Os age, Gangdese, Tibetan plateau.

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Petrology and tectonic significance of the early Mesozoic granulite xenoliths from the eastern Inner Mongolia, china

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Science china Earth sciences 2011年第10期54卷 1484-1491页

作者： SHAO JiAn 1,2 & WEI ChunJing 1 1 The Key Laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education School of Earth and Space sciences, Peking University, beijing 100871, china 2 Key Laboratory of mineral resources, chinese academy of sciences, beijing 100029, china The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University Beijing 100871 China

Granulite xenoliths are found in the early Mesozoic diorite intrusions from Chifeng and Ningcheng areas, eastern Inner Mongolia. The granulites are granoblastic and weakly gneissic with mineral assemblage of hypersthene, diopside, plagioclase and minor biotite, amphibole and ilmenite. Some samples contain the intergrowth composed of labradorite and vermicular hypersthene, and some coarse-grained plagioclases of andesine and labradorite composition occasionally develop bytownite rims with vermicular hypersthene, indicating a possible presence of garnet. Presence of blastogabbroic texture and hypersthene with diopside exsolution lamellae in some samples suggests that the protolith of the granulite is norite or gabbro. On the basis of metamorphic research and thermobaric calculation, the evolution of the granulite xenoliths is summarized into the following stages: (1) Isobaric cooling of underplated noritic or gabbroic magma in the lower crust led to the formation of probable garnet-bearing medium-high pressure granulite. (2) These higher pressure granulites were adiabatically uplifted to upper crust by dioritic magma and transformed to low pressure two-pyroxene granulite during an isothermal decompression. (3) The two-pyroxene granulite underwent retrograde metamorphism of different degrees during an isobaric cooling process as a result of crystallization and cooling of the dioritic magma. The pyroxenite-dominated cumulates and the medium-high pressure granulites may have rejuvenated the lower crust during the early Mesozoic.

关键词： early Mesozoic granulite xenolith lower crust North china Craton

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Natural gas origins of large and medium-scale gas fields in china sedimentary basins

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Science china Earth sciences 2008年第S1期51卷 1-13页

作者： ZHANG ShuiChang &ZHU GuangYou research center of research Institutes of Petrochina exploration and Development,beijing 100083,china research center of research Institutes of Petrochina exploration and Development

china sedimentary basins present abundant natural gas resource thanks to its unique geological *** highly-matured hydrocarbon source rocks,widespread coal-measure strata and low temperature Quaternary saline strata,etc.,indicate the wide foreground of china natural gas resources. Up to now,most of the petroliferous basins have been discovered to have wholesale natural gas accumulation from Precambrian,Paleozoic,Mesozoic to Cenozoic in the east,the central,the west and the coast of *** large and medium-scale gas reservoirs are mainly composed of hydrocarbon gas with big dry coefficient,tiny non-hydrocarbon,wide carbon isotope distribution and varying origin types,the hydrocarbon gas includes coal-formed gas,oil-formed gas,biogenic gas and inorganic gas, ***-formed gas is the main type of china natural gas resources,in particular several explored large-scale gas fields(>100 billion cubic meter)of Kela 2,Sulige and Daniudi,etc.,they all belong to coal-formed gas fields or the gas fields consisting mostly of coal-formed ***-formed gas is also abundant in china marine basins,for example marine natural gas of Sichuan Basin generated from crude oil cracking *** and secondary biogenic gas fields were discovered respectively in the Qaidam Basin and Western Slope of Songliao *** addition,inorganic gases are mainly distributed in the eastern china,in particular the Songliao Basin with abundant carbon dioxide accumulation,indicating that the eastern china present large exploration potential of inorganic gas.

关键词： natural gas origin sedimentary basin large and medium-scale gas field

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Eco－tourism　industry　development──An　alternative　to　sustainable　use　of　landscape　resources

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Journal of Environmental sciences 1996年第3期8卷 298-307页

作者： Lu Yonglong(research center for Eco-Environmental sciences, chineseacademy of sciences, beijing 100085, china) Res. Ctr. for Eco-Environ. sciences Chinese Academy of Sciences Beijing 100085 China

Traditional tourism is a source of not only income and recreation but also environmental pollution and landscape resource destruction. How to leave the same or even better landscape resources to future generations is the key to sustainable development of tourism industry. Ecotourism industry could be an approach to sustainable use of landscape *** connotation of eco-tourism industry and its differences from the traditional tourism in resource use were given in this paper. The ecological planning for Kangyuan recreation area is taken as an example to demonstrate how to make an eco-tourism industry development plan from a system’s point of *** terms of the characteristics of the landscape resources, advantageous geographic location and principles for eco-tourism industry development,a suitable structure of the eco-tourism industry was presented. Based on ecological suitability analysis of the landscape resource use-analysis of capacity and constraint of landscape resources, spatial distribution of the industry sectors was *** the development process, both opportunities and risks exist, cost-benefit analysis is thus made, and cost-effective strategies and policies are provided for the eco-tourism industry development.

关键词： eco-tourism resource use sustainability

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science china Earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural resources Re-search, chinese academy of sciences, beijing 100101, china 2. Institute of Forestry, chinese academy of Forestry sciences, beijing 100091, china 3. Department of Civil Engineering, University of Hong Kong, Hong Kong, china 4. Eco-environmental research center, chinese academy of sciences, beijing 100085, china 5. College of resources and Environment, Southwest Agricultural University, Chongqing 400716, china Correspondence should be addressed to Chen Hao Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Institute of Forestry Chinese Academy of Forestry Sciences Beijing China Department of Civil Engineering University of Hong Kong Hong Kong China Eco-environmental research center Chinese Academy of Sciences Beijing China College of resources and Environment Southwest Agricultural University Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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Environmental problems in a coal mining area affected by coal fires——A case study in Ruqigou Coalfield,Ningxia,china

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Journal of Environmental sciences 1999年第1期11卷 27-36页

作者： Chen Li ding research center for Eco Environmental sciences, chinese academy of sciences, beijing 100085, china

１ＩｎｔｒｏｄｕｃｔｉｏｎＡｓｏｎｅｏｆｔｈｅｍｏｓｔｉｍｐｏｒｔａｎｔｓｏｕｒｃｅｓｆｏｒｐｏｗｅｒｇｅｎｅｒａｔｉｏｎ，ｃｏａｌｍｉｎｉｎｇｉｎｄｕｓｔｒｙｉｓｓｔｉｌｉｎｃｒｅａｓｉｎｇｗｉｔｈｐｏｐｕｌａｔｉ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＡｓｏｎｅｏｆｔｈｅｍｏｓｔｉｍｐｏｒｔａｎｔｓｏｕｒｃｅｓｆｏｒｐｏｗｅｒｇｅｎｅｒａｔｉｏｎ，ｃｏａｌｍｉｎｉｎｇｉｎｄｕｓｔｒｙｉｓｓｔｉｌｉｎｃｒｅａｓｉｎｇｗｉｔｈｐｏｐｕｌａｔｉｏｎｇｒｏｗｔｈａｎｄｅｃｏｎｏｍ...

关键词： Ruqigou Coalfield coal mining coal fire environmental problems land degradation.

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