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The Establishment and Management of Nature Reserves:Crucial Support for the Recovery of the Yangtze Finless Porpoise Population
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作者 FAN Fei ZHENG Jinsong +5 位作者 HAO Yujiang MEI Zhigang LI Songhai ZHOU Shuo WANG Kexiong WANG Ding 《Bulletin of the Chinese Academy of Sciences》 2025年第3期165-172,共8页
The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis)is distributed in the main stream of the middle and lower reaches of the Yangtze River,as well as in Dongting and Poyang lakes.Currently,the mos... The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis)is distributed in the main stream of the middle and lower reaches of the Yangtze River,as well as in Dongting and Poyang lakes.Currently,the most crucial conservation approach involves the establishment and management of both in-situ and ex-situ nature reserves.Since the 1990s,seven nature reserves have been established in the middle and lower reaches of the Yangtze River,covering nearly one-third of its main stream.Additionally,two nature reserves,one in the Dongting Lake and another in the Poyang Lake,have been set up;and three ex-situ nature reserves have been established in three oxbows respectively in Hunan,Hubei,and Anhui provinces.Through measures such as improving the ecological environment quality within the reserves,regulating human activities,and conducting continuous monitoring,the finless porpoise population showed a slight increase in 2022 for the first time.The ex-situ population has continued to grow,with four individuals being released back into the main stream of the Yangtze River after undergoing reintroduction training in 2023.Based on the population development lasting for over three decades,and predictions of future ecological changes,orderly establishment and scientific management of nature reserves have played a key role in and will remain an important basis for the sustaining growth of the finless porpoise population. 展开更多
关键词 The Yangtze finless porpoise nature reserve ex-situ nature reserve population development species conservation
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Electronic Reserves System-基于Web的电子教学参考文献服务系统 被引量:26
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作者 唐承秀 《图书馆工作与研究》 CSSCI 北大核心 2004年第1期50-52,共3页
网络技术的发展使传统的教学参考书服务正在走向数字化 ,这种全新的服务方式将会使高校师生得益匪浅。鉴于我国高校图书馆界正积极着手开展此项服务 ,本文参考了北美目前发展比较成熟的电子教学参考文献服务系统 ,对其系统模式及功能特... 网络技术的发展使传统的教学参考书服务正在走向数字化 ,这种全新的服务方式将会使高校师生得益匪浅。鉴于我国高校图书馆界正积极着手开展此项服务 ,本文参考了北美目前发展比较成熟的电子教学参考文献服务系统 ,对其系统模式及功能特点进行了分析 ,旨在为我国高校图书馆开展此项工作提供借鉴和参考。 展开更多
关键词 Electronic reserves SYSTEM 图书馆 教学参考书 电子文献 文献服务 网络服务
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Ecotourism Development Modes of Nature Reserves 被引量:1
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作者 梅燕 谢萍 《Journal of Landscape Research》 2010年第4期69-72,共4页
Ecotourism is a significant approach for the protective development of nature reserves. Through analyzing the necessity of developing ecotourism, learning from the successful ecotourism development cases of nature res... Ecotourism is a significant approach for the protective development of nature reserves. Through analyzing the necessity of developing ecotourism, learning from the successful ecotourism development cases of nature reserves in China and abroad, the authors proposed a new Nature Reserve Protective Tourism Exploring Mode (NRPTEM) with the integration of "protection, development and management", such a mode contains 3 systems (protection, development and management), 12 projects (biodiversity protection, geological remains protection, protection of human ecology, environment monitoring, scientific planning, product development, market expansion, facility construction, capacity building, community co-management, environment education and management innovation) as well as human (a critical structural factor). The relationship between these items in the complicated process of ecotourism development of nature reserves was elaborated, and the dominant role of human factors in the 3 systems was also put forward. 展开更多
关键词 NATURE reserves ECOTOURISM DEVELOPMENT MODE
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美国E-reserves版权政策调研及启示 被引量:1
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作者 王英 《大学图书馆学报》 CSSCI 北大核心 2013年第3期14-21,共8页
调研美国版权局、图书馆协会及数十所高校的E-reserves版权政策,对提交E-reserve材料的要求、E-reserve材料的范围和数量限制、E-reserve系统的访问、E-reserve材料的存储和再利用、部分E-reserve材料获得版权许可等方面的政策进行分析... 调研美国版权局、图书馆协会及数十所高校的E-reserves版权政策,对提交E-reserve材料的要求、E-reserve材料的范围和数量限制、E-reserve系统的访问、E-reserve材料的存储和再利用、部分E-reserve材料获得版权许可等方面的政策进行分析,并在此基础上探讨美国E-re-serves版权政策对我国的启示,包括发挥中国图书馆学会的行业领导作用、高校应制定自己的E-reserve政策、明确需要授权的材料、明晰E-reserve系统的权利与义务关系等内容。 展开更多
关键词 E—reserve材料 E—reserve系统 版权政策
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Noradrenergic excitation of astrocytes supports cognitive reserve
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作者 Robert Zorec Alexei Verkhratsky 《Neural Regeneration Research》 2026年第4期1546-1547,共2页
The concept of the brain cognitive reserve is derived from the well-acknowledged notion that the degree of brain damage does not always match the severity of clinical symptoms and neurological/cognitive outcomes.It ha... The concept of the brain cognitive reserve is derived from the well-acknowledged notion that the degree of brain damage does not always match the severity of clinical symptoms and neurological/cognitive outcomes.It has been suggested that the size of the brain(brain reserve) and the extent of neural connections acquired through life(neural reserve) set a threshold beyond which noticeable impairments occur.In contrast,cognitive reserve refers to the brain's ability to adapt and reo rganize stru cturally and functionally to resist damage and maintain function,including neural reserve and brain maintenance,resilience,and compensation(Verkhratsky and Zorec,2024). 展开更多
关键词 ASTROCYTES brain reserve cognitive reserve clinical symptoms noradrenergic excitation neural reserve neural connections brain cognitive reserve
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Liupan Mountain National Nature Reserve
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《ChinAfrica》 2026年第3期62-63,共2页
Located in southern Ningxia Hui Autonomous Region,northwest China,the Liupan Mountain National Nature Reserve covers a total area of 26,783.64 hectares.Established in 1982 and upgraded to national status in 1988,it pr... Located in southern Ningxia Hui Autonomous Region,northwest China,the Liupan Mountain National Nature Reserve covers a total area of 26,783.64 hectares.Established in 1982 and upgraded to national status in 1988,it protects a vital temperate mountainous forest ecosystem on the Loess Plateau.The reserve is centred around the Liupan Mountain range,one of China’s youngest mountain chains,formed by Himalayan tectonic movements. 展开更多
关键词 National Nature Reserve Loess Plateau Northwest China Southern Ningxia Hui Autonomous Region temperate mountainous forest nature reserve himalayan tectonic movements Liupan Mountain
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FIGURES
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《China's Foreign Trade》 2026年第1期2-5,共4页
3,399.1 billion According to data released by the State Administration of Foreign Exchange(SAFE),China’s foreign exchange reserves stood at USD 3,399.1 billion at the end of January 2026,an increase of USD 41.2 billi... 3,399.1 billion According to data released by the State Administration of Foreign Exchange(SAFE),China’s foreign exchange reserves stood at USD 3,399.1 billion at the end of January 2026,an increase of USD 41.2 billion from the previous month. 展开更多
关键词 foreign exchange reserves China state administration foreign exchange January
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CT-derived fractional flow reserve combined with atherosclerotic extent to determine long-term outcomes in diabetic patients with coronary artery disease
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作者 Zhi-Qiang WANG Zhen-Nan LI +1 位作者 Zhi-Hui HOU Bin LU 《Journal of Geriatric Cardiology》 2026年第1期27-35,共9页
Background There is still limited data on predictive value of coronary computed tomography angiography(CCTA)–derived fractional flow reserve(CT-FFR) for long term outcomes. We examined the long-term prognostic value ... Background There is still limited data on predictive value of coronary computed tomography angiography(CCTA)–derived fractional flow reserve(CT-FFR) for long term outcomes. We examined the long-term prognostic value of CT-FFR combined with CCTA–defined atherosclerotic extent in diabetic patients with coronary artery disease(CAD).Methods A retrospective pooled analysis of individual patient data was performed. Deep-learning-based vessel-specific CTFFR was calculated. All patients enrolled were followed-up for at least 5 years. Predictive abilities for major adverse cardiac events(MACE) were compared among three models(model 1), constructed using clinical variables;model 2, model 1+CCTA–derived atherosclerotic extent(Leiden risk score);and model 3, model 2+CT-FFR.Results A total of 480 diabetic patients [median age, 61(55–66) years;52.9% men] were included. During a median follow-up time of 2197(2126–2355) days, 55 patients(11.5%) experienced MACE. In multivariate-adjusted Cox models, Leiden risk score(HR: 1.06;95% CI: 1.01–1.11;P = 0.013) and CT-FFR ≤ 0.80(HR: 6.54;95% CI: 3.18–13.45;P < 0.001) were the independent predictors. The discriminant ability was higher in model 2 than in model 1(C-index, 0.75 vs. 0.63;P < 0.001) and was further promoted by adding CT-FFR to model 3(C-index, 0.81 vs. 0.75;P = 0.002). Net reclassification improvement(NRI) was 0.19(P = 0.009) for model 2 beyond model 1. Of note, adding CT-FFR to model 3 also exhibited significantly improved reclassification compared with model 2(NRI = 0.14;P = 0.011).Conclusion In diabetic patients with CAD, CT-FFR provides robust and incremental prognostic information for predicting longterm outcomes. The combined model exhibits improved prediction abilities, which is beneficial for risk stratification. 展开更多
关键词 fractional flow reserve ct ffr coronary artery disease cad methods tomography angiography ccta derived coronary artery disease atherosclerotic extent fractional flow reserve diabetic patients coronary computed tomography angiography
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NATURE’S GIFT:NATURAL WONDERS IN CHINA AND AFRICA
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《ChinAfrica》 2026年第2期62-63,共2页
CHINA Wuliangshan National Nature Reserve Spanning a significant altitudinal range from 1,600 to 3,371 metres and encompassing a total area of 31,585 hectares,the Wuliangshan National Nature Reserve protects one of th... CHINA Wuliangshan National Nature Reserve Spanning a significant altitudinal range from 1,600 to 3,371 metres and encompassing a total area of 31,585 hectares,the Wuliangshan National Nature Reserve protects one of the most intact and pristine forest ecosystems in southern Yunnan Province. 展开更多
关键词 nature reserve Wuliangshan forest ecosystem Yunnanprovince
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Quiet Revival
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《ChinAfrica》 2026年第1期4-5,共2页
Elk are seen at the Tian’ezhou National Nature Reserve for Elk in Shishou,Hubei Province,on 27 November 2025.The reserve’s elk population has risen from just 64 in the 1990s to more than 4,500 today.
关键词 hubei province ELK tianezhou national nature reserve shishou quiet revival population rise s
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NATURAL WONDERS IN CHINA AND AFRICA
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《ChinAfrica》 2026年第1期62-63,共2页
CHINA.Dinghu Mountain National Nature Reserve.Located in Zhaoqing,Guangdong Province,Dinghu Mountain National Nature Reserve is a pristine natural sanctuary spanning 1,133 hectares within the low mountain ranges of th... CHINA.Dinghu Mountain National Nature Reserve.Located in Zhaoqing,Guangdong Province,Dinghu Mountain National Nature Reserve is a pristine natural sanctuary spanning 1,133 hectares within the low mountain ranges of the Dayunwu Mountains. 展开更多
关键词 Guangdong Province low mountain ranges Dayunwu Mountains natural sanctuary Zhaoqing Dinghu Mountain National Nature Reserve
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New Findings from China's Second Qinghai-Xizang Plateau Scientific Expedition Unveiled
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作者 Xian Gan(Text/Photos) CTIS(Translated) 《China's Tibet》 2026年第1期50-53,共4页
The Qinghai-Xizang Plateau,known as the Roof of the World and the Water Tower of Asia,is recognized as the Earth’s Third Pole.It functions as a vital ecological security barrier and a strategic resource reserve for C... The Qinghai-Xizang Plateau,known as the Roof of the World and the Water Tower of Asia,is recognized as the Earth’s Third Pole.It functions as a vital ecological security barrier and a strategic resource reserve for China,while also serving as an important conservation area that reflects the unique culture of the Chinese nation.Conducting the Second Comprehensive Scientific Expedition to the Qinghai-Xizang Plateau is essential for understanding valuable insights into scientific protection of the region. 展开更多
关键词 understanding valuable insights scientific protection water tower Qinghai Xizang Plateau ecological security unique culture strategic resource reserve scientific expedition
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Review of tungsten resource reserves,tungsten concentrate production and tungsten beneficiation technology in China 被引量:38
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作者 Xu WANG Wen-qing QIN +4 位作者 Fen JIAO Liu-yang DONG Jian-gen GUO Jian ZHANG Cong-ren YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第7期2318-2338,共21页
Tungsten is a strategic metal that is widely used in various fields such as electron communication,aeronautics and astronautics,materials and chemical engineering,due to its special properties.China has the largest re... Tungsten is a strategic metal that is widely used in various fields such as electron communication,aeronautics and astronautics,materials and chemical engineering,due to its special properties.China has the largest reserves of tungsten resources and the largest output of tungsten concentrate in the world,and plays a decisive role in the world tungsten market.In this work,firstly,the reserves and distribution characteristics of tungsten resources in China were summarized,and the production situation of tungsten concentrate in China was reviewed.Based on the gross domestic product per capita(GDP/capita),five different annual GDP growth rates were used to estimate China’s tungsten concentrate production in the future.The estimation results suggested that if China’s economy continues to grow at the current rate,the accumulative production of tungsten concentrate will exceed current reserves by approximately 2032.Then,from the aspects of process flow,beneficiation equipment and flotation reagents,the beneficiation technology development of different types of tungsten ore in China was also reviewed,including wolframite,scheelite and tungsten-bearing slime.Finally,taking several representative tungsten mines in China as examples,the classic beneficiation technology of different types of tungsten ores was elucidated in detail.Meanwhile,the development direction of tungsten beneficiation technology in the future was put forward,which was of great significance to maintain the superiority of tungsten resources in China. 展开更多
关键词 TUNGSTEN reserves PRODUCTION BENEFICIATION FLOTATION gravity separation
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Application of 3-D Geoscience Modeling Technology for the Estimation of Solid Mineral Reserves 被引量:17
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作者 PAN Mao LI Jun +1 位作者 WANG Zhangang JIN Jiangjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期655-660,共6页
Applying new approaches, methods, and technologies for the estimation of reserves can effectively improve the efficiency and accuracy of assessments of solid mineral resources. After analyzing the development of 3-D g... Applying new approaches, methods, and technologies for the estimation of reserves can effectively improve the efficiency and accuracy of assessments of solid mineral resources. After analyzing the development of 3-D geoscience modeling technology (3-D GMT), this paper discusses the application of 3-D GMT for the estimation of solid mineral reserves, emphatically introducing its workflow and two key technologies, 3-D orebody surface modeling, and property modeling. Moreover, the paper analyzes the limitations of traditional methods, such as the section method and geological block method, and points out the advantages of 3-D GMT: building more accurate 3-D orebody models, expressing the internal inhomogeneous attributes of an orebody, reducing the potential for errors in the estimation of reserves, and implementing dynamic estimations of reserves. 展开更多
关键词 3-D geoscience modeling solid mineral resource estimation of reserves surface modeling property modeling
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Land-cover changes of national nature reserves in China 被引量:9
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作者 FAN Zemeng ZHANG Xuan +4 位作者 LI Jing YUE Tianxiang LIU Jiyuan XIANG Bao KUANG Wenhui 《Journal of Geographical Sciences》 SCIE CSCD 2013年第2期258-270,共13页
For preventing ecosystem degradation, protecting natural habitats and conserving biodiversity within the habitats, 2588 nature reserves have been established in China at the end of 2010. The total area is up to 149.44... For preventing ecosystem degradation, protecting natural habitats and conserving biodiversity within the habitats, 2588 nature reserves have been established in China at the end of 2010. The total area is up to 149.44 million ha and covers over 15% of Chinese terrestrial surface. Land-cover change, as the primary driver of biodiversity change, directly impacts ecosystem structures and functions. In this paper, 180 National Nature Reserves (NNRs) are selected and their total area is 44.71 million ha, accounting for 29.9% of all NNRs in China. In terms of the ecosystem characteristics and their major protected object, all selected NNRs are classified into 7 types. A Positive and Negative Change Index of Land-cover (PNCIL) was developed to analyze the land-cover change of each NNRs type from the late 1980s to 2005. The results show that the land-cover of all selected NNRs types have degradated to a certain degree except the forest ecosystem reserves with a decreasing rate, but the rate of degrada tion alleviated gradually. The mean positive and negative change rates of land-cover in all core zones decreased by 0.69% and 0.16% respectively. The landscape pattern of land-cover in the core zones was more stable than that in the buffer zones and the experimental zones. Furthermore, the ecological diversity and patch connectivity of land-cover in selected NNRs increased generally. In short, the land-cover of 180 selected NNRs in China had a beneficial chan qe trend after NNRs established, especially between 1995 and 2005. 展开更多
关键词 national nature reserves land-cover changes EVALUATION China
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Siting of Dark Sky Reserves in China Based on Multi-source Spatial Data and Multiple Criteria Evaluation Method 被引量:5
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作者 WEI Ye CHEN Zuoqi +2 位作者 XIU Chunliang YU Bailang LIU Hongxing 《Chinese Geographical Science》 SCIE CSCD 2019年第6期949-961,共13页
With the rapid development of population and urbanization and the progress of lighting technology, the influence of artificial light sources has increased.In this context, the problem of light pollution has attracted ... With the rapid development of population and urbanization and the progress of lighting technology, the influence of artificial light sources has increased.In this context, the problem of light pollution has attracted wide attention.Previous studies have revealed that light pollution can affect biological living environments, human physical and mental health, astronomical observations and many other aspects.Therefore, organizations internationally have begun to advocate for measures to prevent light pollution, many of which are recognized by the International Dark-Sky Association(IDA).In addition to improving public awareness, legal protections, technical treatments and other means, the construction of Dark Sky Reserves(DSR) has proven to be an effective preventive measure.So far, as a pioneer practice in this field, the IDA has identified 11 DSRs worldwide.Based on the DA requirements for DSRs, this paper utilizes NPP-VIIRS nighttime light data and other multi-source spatial data to analyze possible DSR sites in China.The land of China was divided into more than ten thousand 30 km × 30 km fishnets, and constraint and suitable conditions were designated, respectively, as light and cloud conditions, and scale, traffic and attractiveness conditions.Using a multiple criteria evaluation, 1443 fishnets were finally selected as most suitable sites for the construction of DSRs.Results found that less than 25% of China is not subject to light pollution, and less than 13% is suitable for DSR construction, primarily in western and northern areas, including Tibet, Xinjiang, Qinghai, Gansu and Inner Mongolia. 展开更多
关键词 DARK SKY reserves light POLLUTION NPP-VIIRS siting multiple criteria evaluation China
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Evaluating Conservation Effectiveness of Nature Reserves Established for Surrogate Species:Case of a Giant Panda Nature Reserve in Qinling Mountains,China 被引量:12
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作者 XU Weihua Andrés VIA +4 位作者 QI Zengxiang OUYANG Zhiyun LIU Jianguo LIU Wei WAN Hui 《Chinese Geographical Science》 SCIE CSCD 2014年第1期60-70,共11页
Many nature reserves are established to protect the habitat needs of particular endangered species of interest but their effectiveness for protecting other species is questionable.In this study,this effectiveness was ... Many nature reserves are established to protect the habitat needs of particular endangered species of interest but their effectiveness for protecting other species is questionable.In this study,this effectiveness was evaluated in a nature reserve network located in the Qinling Mountains,Shaanxi Province,China.The network of reserves was established mainly for the conservation of the giant panda,a species considered as a surrogate for the conservation of many other endangered species in the region.The habitat suitability of nine protected species,including the giant panda,was modeled by using Maximum Entropy(MAXENT)and their spatial congruence was analyzed.Habitat suitability of these species was also overlapped with nature reserve boundaries and their management zones(i.e.,core,buffer and experimental zones).Results show that in general the habitat of the giant panda constitutes a reasonable surrogate of the habitat of other protected species,and giant panda reserves protect a relatively high proportion of the habitat of other protected species.Therefore,giant panda habitat conservation also allows the conservation of the habitat of other protected species in the region.However,a large area of suitable habitat was excluded from the nature reserve network.In addition,four species exhibited a low proportion of highly suitable habitat inside the core zones of nature reserves.It suggests that a high proportion of suitable habitat of protected species not targeted for conservation is located in the experimental and buffer zones,thus,is being affected by human activities.To increase their conservation effectiveness,nature reserves and their management zones need to be re-examined in order to include suitable habitat of more endangered species.The procedures described in this study can be easily implemented for the conservation of many endangered species not only in China but in many other parts of the world. 展开更多
关键词 giant panda habitat suitability Maximum Entropy(MAXENT) nature reserve network surrogate species
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Assessment of effectiveness of nature reserves on the Tibetan Plateau based on net primary production and the large sample comparison method 被引量:7
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作者 张镱锂 胡忠俊 +7 位作者 祁威 吴雪 摆万奇 李兰晖 丁明军 刘林山 王兆锋 郑度 《Journal of Geographical Sciences》 SCIE CSCD 2016年第1期27-44,共18页
Twenty-one typical coupled large samples were chosen from areas within and surrounding nature reserves on the Tibetan Plateau using the large sample comparison method(LSCM).To evaluate the effectiveness of the nature ... Twenty-one typical coupled large samples were chosen from areas within and surrounding nature reserves on the Tibetan Plateau using the large sample comparison method(LSCM).To evaluate the effectiveness of the nature reserves in protecting the ecological environment,the alpine grassland net primary production(NPP) of these coupled samples were compared and the differences between them before and after their establishment as protected areas were analyzed.The results showed that:(1) With respect to the alpine grassland NPP,the ecological and environmental conditions of most nature reserves were more fragile than those of the surrounding areas and also lower than the average values for the Tibetan Plateau.(2) Of the 11 typical nature reserves selected,the positive trend in the NPP for Manzetang was the most significant,whereas there was no obvious trend in Taxkorgan.With the exception of Selincuo,the annual NPP growth rate in the nature reserves covered by alpine meadow and wetland was higher than that in nature reserves consisting of alpine steppe and alpine desert.(3) There were notable findings in 21 typical coupled samples:(a) After the establishment of the nature reserves,the annual rate of increase in the NPP in 76% of samples inside nature reserves and 82% of samples inside national nature reserves was higher than that of the corresponding samples outside nature reserves.(b) The effectiveness of ecological protection of the Mid-Kunlun,Changshagongma,Zoige and Selincuo(Selin Co) nature reserves was significant; the effectiveness of protection was relatively sig-nificant in most parts of the Sanjiangyuan and Qiangtang nature reserves,whereas in south-east Manzetang and north Taxkorgan the protection effectiveness was not obvious.(c) The ecological protection effectiveness was significant in nature reserves consisting of alpine meadow,but was weak in nature reserves covered by alpine steppe.This study also shows that the advantage of large sample comparison method in evaluating regional ecology change.Careful design of the samples used,to ensure comparability between the samples,is crucial to the success of this LSCM. 展开更多
关键词 nature reserves protection effectiveness large sample comparison method net primary production Tibetan Plateau
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A Volumetric Model for Evaluating Tight Sandstone Gas Reserves in the Permian Sulige Gas Field,Ordos Basin,Central China 被引量:6
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作者 CUI Mingming FAN Aiping +3 位作者 WANG Zongxiu GAO Wanli LI Jinbu LI Yijun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第2期386-399,共14页
To accurately measure and evaluate reserves is critical for ensuring successful production of unconventional oil and gas. This work proposes a volumetric model to evaluate the tight sandstone gas reserves of the Permi... To accurately measure and evaluate reserves is critical for ensuring successful production of unconventional oil and gas. This work proposes a volumetric model to evaluate the tight sandstone gas reserves of the Permian Sulige gas field in the Ordos Basin. The reserves can be determined by four major parameters of reservoir cutoffs, net pay, gas-bearing area and compression factor Z, which are controlled by reservoir characteristics and sedimentation. Well logging, seismic analysis, core analysis and gas testing, as well as thin section identification and SEM analysis were used to analyze the pore evolution and pore-throat structure. The porosity and permeability cutoffs are determined by distribution function curve,empirical statistics and intersection plot. Net pay and gas-bearing area are determined based on the cutoffs, gas testing and sand body distribution, and the compression factor Z is obtained by gas component. The results demonstrate that the reservoir in the Sulige gas field is characterized by ultralow porosity and permeability, and the cutoffs of porosity and permeability are 5% and 0.15×10^(–3) μm^2, respectively. The net pay and gas-bearing area are mainly affected by the sedimentary facies, sand body types and distribution. The gas component is dominated by methane which accounts for more than 90%, and the compression factor Z of H_8(P_2h_8) and S_1(P_1s_1) are 0.98 and 0.985, respectively. The distributary channels stacked and overlapped, forming a wide and thick sand body with good developed intergranular pores and intercrystalline pores. The upper part of channel sand with good porosity and permeability can be sweet spot for gas exploration. The complete set of calculation systems proposed for tight gas reserve calculation has proved to be effective based on application and feedback. This model provides a new concept and consideration for reserve prediction and calculation in other areas. 展开更多
关键词 tight sandstone reservoir volumetric GAS reserve PERMIAN SULIGE GAS field ORDOS Basin
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Impacts of the Wenchuan Earthquake on the Giant Panda Nature Reserves in China 被引量:11
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作者 DENG Xiangzheng JIANG Qunou +1 位作者 GE Quansheng YANG LinSheng 《Journal of Mountain Science》 SCIE CSCD 2010年第2期197-206,共10页
The Wenchuan Earthquake that occurred in May of 2008 caused damages to large areas of Sichuan,Gansu,and Shaanxi provinces in China.Reports from local governments and related management agencies show that the giant pan... The Wenchuan Earthquake that occurred in May of 2008 caused damages to large areas of Sichuan,Gansu,and Shaanxi provinces in China.Reports from local governments and related management agencies show that the giant panda nature reserves in the earthquake-hit areas were heavily damaged.Our estimates in this paper of the impacts of the earthquake on the giant panda in the earthquake-hit areas were made based on the interpretation of remote sensing images and information collected by field survey.A rapid assessment method was designed to estimate the damages of the earthquake on giant panda habitats.By using visual interpretation methods,we decoded the remote sensing images of the disaster area in the 49 giant panda nature reserves.Research results showed that the Wenchuan Earthquake and the succeeding secondary geological disasters caused great damages to the giant panda nature reserves and disturbed the normal life of the giant pandas there (e.g.,landscape fragmentation increased significantly).Undoubtedly,the life of the giant pandas there was affected.However,although the earthquake caused certain impacts on the giant pandas,it did not really threat their survival.Even so,we still strongly advocate for protection of the giant pandas,and have prioritized a couple of measures to be taken to restore the giant panda nature reserves in the earthquake-hit areas. 展开更多
关键词 Wenchuan earthquake Remote sensing Giant panda Giant panda nature reserve Rapid assessment method
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