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基于Zonation-MSPA耦合模型的甘肃沿黄地区生态安全格局构建与评估 被引量:8
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作者 俞金凤 杜怀玉 +1 位作者 王家亮 张媛 《环境科学》 北大核心 2025年第5期3085-3097,共13页
为了有效实现国土空间生态保护与修复,探讨国土空间生态安全格局构建与评估的方法,提出针对性修复策略,对维护国家生态安全具有重要意义.以甘肃沿黄地区为例,基于生态系统服务重要性和生态敏感性,耦合Zonation-MSPA模型识别生态源地,利... 为了有效实现国土空间生态保护与修复,探讨国土空间生态安全格局构建与评估的方法,提出针对性修复策略,对维护国家生态安全具有重要意义.以甘肃沿黄地区为例,基于生态系统服务重要性和生态敏感性,耦合Zonation-MSPA模型识别生态源地,利用电路理论提取生态廊道、生态夹点和生态屏障点,构建生态安全格局并采用图论法评估生态安全格局,识别和确定研究区域的国土空间生态保护修复关键区域.结果表明:①甘肃沿黄地区共提取到生态源地60个,生态廊道共112条,其中关键生态廊道43条;②甘肃沿黄地区生态安全格局大体表现为“三纵-四横-三区”的空间特征,形成的网络回路和连通度都处于中等水平;③识别出的甘肃沿黄地区生态保护修复关键区域包括:生态夹点126个,主要集中分布在陇中地区,现状用地主要为耕地和草地,生态夹点周边区域的现状用地大多为建设用地;生态障碍点共475个,其中一级障碍点106个,二级障碍点369个,现状用地主要为耕地、草地及河道.结合研究区生态保护修复关键区域的空间分布特征以及待修复的现状地类,分别提出各类生态保护修复关键区域的修复措施,可为黄河流域生态安全格局优化及生态修复提供借鉴. 展开更多
关键词 国土空间生态修复 生态安全格局 zonation模型 MSPA模型 电路理论 图论法
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基于调节服务价值与Zonation模型的川西高原生态源地识别
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作者 李蓝星 易桂花 +3 位作者 张廷斌 别小娟 王国严 张宸源 《测绘科学》 北大核心 2025年第9期161-169,共9页
针对当前传统研究无法顾及生态源地的天然存在价值与空间连通性需求,导致生态源地空间分布碎片化的问题,以川西高原为研究区,通过生态系统调节服务价值量化生态系统功能,结合Zonation模型优化生态源地景观连通性,提出了基于生态系统调... 针对当前传统研究无法顾及生态源地的天然存在价值与空间连通性需求,导致生态源地空间分布碎片化的问题,以川西高原为研究区,通过生态系统调节服务价值量化生态系统功能,结合Zonation模型优化生态源地景观连通性,提出了基于生态系统调节服务价值和Zonation模型的生态源地识别框架。共识别川西高原生态源地86处,面积为3.72×10^(4)km^(2),占川西高原总面积的16%。对比论证表明,Zonation模型通过保留核心区域降低了源地破碎化,其识别结果比未应用该模型的方法具有更好的景观连通性。研究结果可为构建川西高原生态安全格局构建提供方法支持。 展开更多
关键词 生态系统调节服务价值 zonation模型 生态源地 川西高原
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Alteration and Metallogenic Zonation in Magmatic-Hydrothermal Ore Systems:Scientific Understandings and Exploration Implications
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作者 Degao Zhai Jinchao Wu +7 位作者 Qingqing Zhao Panagiotis Voudouris Stylianos Tombros Xinli Wang Wangjie Chen Jinghao Sun Zhan Xu Jiajun Liu 《Journal of Earth Science》 2025年第3期1303-1308,共6页
The patterns of metal distribution and alteration zonation in magmatic-hydrothermal systems primarily focus on porphyry deposit and other closely associated types,such as skarn,epithermal and distal vein deposits(e.g.... The patterns of metal distribution and alteration zonation in magmatic-hydrothermal systems primarily focus on porphyry deposit and other closely associated types,such as skarn,epithermal and distal vein deposits(e.g.,Zheng,2022;Hutchison et al.,2020;Cooke et al.,2011;Hedenquist et al.,1998). 展开更多
关键词 metallogenic zonation distal vein deposits egzheng hutchison epithermal magmatic hydrothermal ore systems porphyry deposit skarn alteration zonation ALTERATION
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Analysis and Zonation of Freeze–Thaw Action in the Chinese Plateau Region Considering Spatiotemporal Climate Characteristics
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作者 Tiejun Liu Ming Zhang +2 位作者 Dujian Zou Jiaping Liu Jinping Ou 《Engineering》 SCIE EI CAS CSCD 2024年第11期308-325,共18页
Concerns about the durability of transportation infrastructure due to freeze-thaw(F-T)cycles are particu-larly significant in the Chinese plateau region,where concrete aging and performance deterioration pose substant... Concerns about the durability of transportation infrastructure due to freeze-thaw(F-T)cycles are particu-larly significant in the Chinese plateau region,where concrete aging and performance deterioration pose substantial challenges.The current national standards for the frost resistance design of concrete struc-tures are based predominantly on the coldest monthly average temperature and do not adequately address the comprehensive effects of the spatiotemporal variance,amplitude,and frequency of F-T cycles.To address this issue,this study introduced a spatiotemporal distribution model to analyze the long-term impact of F-T action on concrete structures by employing statistical analysis and spatial inter-polation techniques.Cluster analysis was applied to create a nationwide zonation of F-T action level from data on the freezing temperature,temperature difference,and the number of F-T cycles.Furthermore,this study explored the similarity between natural environmental conditions and laboratory-accelerated tests using hydraulic pressure and cumulative damage theories.A visualization platform that incorporates tools for meteorological data queries,environmental characteristic analyses,and F-T action similarity calculations was designed.This research lays theoretical groundwork and provides technical guidance for assessing service life and enhancing the quantitative durability design of concrete structures in the Chinese plateau region. 展开更多
关键词 Concrete durability Freeze-thaw(F-T) Environmental characteristics SIMILARITY zonation
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Durability zonation standard of concrete structure design 被引量:4
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作者 金伟良 吕清芳 《Journal of Southeast University(English Edition)》 EI CAS 2007年第1期98-104,共7页
Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions an... Durability zonation standard (DZS) is proposed to provide useful parameters for durable concrete structure design. It deals not only with the influence of environment on structures, but also with types, functions and importance of structures based on the theory of life cycle cost(LCC). First, the basic concept of DZS for concrete structure design is defined. Then the basic principles for DZS are established. The factors for zonation according to natural environmental conditions and structural importance are identified. The usefulness of DZS by citing a real application for concrete highway bridges in Zhejiang Province is demonstrated. Finally, durability regulations are provided accordingly to zonation. 展开更多
关键词 durability zonation standard concrete structure design zonation map life cycle cost
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uniLIVER:a human liver cell atlas for data-driven cellular state mapping
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作者 Yanhong Wu Yuhan Fan +15 位作者 Yuxin Miao Yuman Li Guifang Du Zeyu Chen Jinmei Diao Yu-Ann Chen Mingli Ye Renke You Amin Chen Yixin Chen Wenrui Li Wenbo Guo Jiahong Dong Xuegong Zhang Yunfang Wang Jin Gu 《Journal of Genetics and Genomics》 2025年第9期1133-1147,共15页
The liver performs several vital functions such as metabolism,toxin removal,and glucose storage through the coordination of various cell types.With the recent breakthrough of the single-cell/single-nucleus RNAseq(sc/s... The liver performs several vital functions such as metabolism,toxin removal,and glucose storage through the coordination of various cell types.With the recent breakthrough of the single-cell/single-nucleus RNAseq(sc/snRNA-seq)techniques,there is a great opportunity to establish a reference cell map of the liver at single-cell resolution with transcriptome-wise features.In this study,we build a unified liver cell atlas uniLIVER(http://lifeome.net/database/uniliver)by integrative analysis of a large-scale sc/snRNA-seq data collection of normal human liver with 331,125 cells and 79 samples from 6 datasets.Moreover,we introduce LiverCT,a machine learning based method for mapping any query dataset to the liver reference map by introducing the definition of“variant”cellular states analogous to the sequence variants in genomic analysis.Applying LiverCT on liver cancer datasets,we find that the“deviated”states of T cells are highly correlated with the stress pathway activities in hepatocellular carcinoma,and the enrichments of tumor cells with the hepatocyte-cholangiocyte“intermediate”states significantly indicate poor prognosis.Besides,we find that the tumor cells of different patients have different zonation tendencies and this zonation tendency is also significantly associated with the prognosis.This reference atlas mapping framework can also be extended to any other tissues. 展开更多
关键词 Liveratlas Reference mapping Abnormal state identification Patient stratification Hepatic zonation
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Assessment of ecological geological vulnerability in Mu Us Sandy Land based on GIS and suggestions of ecological protection and restoration
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作者 Jian-yu Liu Hong-feng Nie +6 位作者 Liang Xu Chun-lei Xiao Wei Li Guo-li Yuan Yan-peng Huang Xin-yang Ji Tian-qi Li 《China Geology》 2025年第1期117-140,共24页
Eco-geological vulnerability assessment is a significant research topic within the field of eco-geology,but it remains poorly studied.The Mu Us Sandy Land,located in the central part of the farming-pastoral ecotone in... Eco-geological vulnerability assessment is a significant research topic within the field of eco-geology,but it remains poorly studied.The Mu Us Sandy Land,located in the central part of the farming-pastoral ecotone in northern China,plays a critical role in maintaining the ecological security pattern in this region.However,this sandy land also faces severe sandy desertification and ecological degradation.This study conducted a regional eco-geological vulnerability assessment of the Mu Us Sandy Land using a comprehensive index evaluation method based on eco-geological theories and survey results.To construct an appropriate index system for the eco-geological vulnerability assessment of the Mu Us Sandy Land,the study considered the sandy land’s unique characteristics and identified 15 factors of five categories,namely geology,meteorology,soil,topography,and vegetation.The paper calculated the comprehensive weights of all the indices using the analytic hierarchy process(AHP)and the entropy weight method(EWM).Furthermore,it established the eco-geological vulnerability index(EGVI)and obtained the assessment results.The results showed that the eco-geological vulnerability of the Mu Us Sandy Land gradually intensifies from east to west,manifested as vulnerable eco-geological conditions overall.Specifically,extremely vulnerable zones are found in the northwestern and southeastern parts of the study area,highly vulnerable zones in the western and southern parts,moderately vulnerable zones in the central part,and slightly and potentially vulnerable zones in the eastern and southern parts.Areas with high spatial autocorrelations include the northern Uxin Banner-Otog Banner-Angsu Town area,the surrounding areas of Hongdunjie Town in the southeastern part of the study area,the Hongshiqiao Township-Xiaohaotu Township area,Otog Front Banner,and Bainijing Town,which should be prioritized in the ecological conservation and restoration.Additionally,the paper proposed suggestions for the ecological conservation and restoration of county-level administrative areas in the study area.Overall,the findings provide a valuable reference for the ecological conservation and restoration of the Mu Us Sandy Land and other desert areas in arid and semi-arid regions. 展开更多
关键词 Eco-geological vulnerability Analytic hierarchy process Entropy weight method Evaluation and zonation Mu Us Sandy Land Geology-meteorology-soil-topography-vegetation Precipitation and groundwater Environmental protection and restoration Environmental restoration engineering Inner Mongolia Plateau
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基于生境质量的干旱区绿洲保护规划——以和田绿洲为例
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作者 阿布都克由木·阿布力孜 阿地力·买买提 +2 位作者 王锐 苗志国 张思源 《地下水》 2025年第1期224-228,共5页
生态保护规划是保证干旱区生态安全、实现区域可持续发展的重要方法。和田绿洲是南疆干旱区民众重要的生活场所,其生态环境及其脆弱,易受环境与人为因素的破坏。考虑到和田绿洲的重要性,本文基于生态环境稳定与生态保护效率最大化的目标... 生态保护规划是保证干旱区生态安全、实现区域可持续发展的重要方法。和田绿洲是南疆干旱区民众重要的生活场所,其生态环境及其脆弱,易受环境与人为因素的破坏。考虑到和田绿洲的重要性,本文基于生态环境稳定与生态保护效率最大化的目标下,运用土地覆盖类型数据与遥感影像数据,计算和田绿洲NDVI与连通度,随后运用Zonation生成生境质量优先级序列,再基于生境质量生成和田绿洲生态保护优先级序列。结果表明:(1)和田绿洲植被主要类型为农作物、草地、灌木和林地这4个类型,权重值分别为50.648%、26.505%、14.241%和8.605%;(2)和田绿洲整体NDVI值较高,绿洲大部分区域NDVI值在0.5以上,喀拉喀什河和田县与墨玉县交界区域NDVI值达到0.6以上。高连通性区域主要分布在喀拉喀什河和田县与墨玉县交界区域,随着中心向外扩展,连通性逐渐降低。第十四师昆玉市虽然位于和田绿洲西部边缘处,远离喀拉喀什河,但是其连通性相较于周围较高;(3)和田绿洲的生境高优先级序列与农作物和草地的高优先级序列高度重合,生态保护优先级高的区域主要位于喀拉喀什河和田县与墨玉县交界区处,生境高优先级区域外围的环状区域。在未来生态保护规划构建中,应重点保护生态保护优先级高的区域,以期实现和田绿洲生境的稳定与生态保护效率的最大化,为其它干旱区绿洲生态保护规划的构建提供借鉴。 展开更多
关键词 生态保护规划 和田绿洲 zonation 生态保护优先级序列
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基于ZONATION的岷山山系多物种保护规划 被引量:14
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作者 肖静 崔莉 李俊清 《生态学报》 CAS CSCD 北大核心 2016年第2期420-429,共10页
空间布局不尽合理是我国的自然保护区发展面临的问题之一,优化现有的自然保护区体系是在资源有限的情况下实现自然保护区的保护效益最大化的最佳途径。以岷山地区为主要研究区域,以25种珍稀濒危物种为主要研究对象,通过MAXENT与ZONATIO... 空间布局不尽合理是我国的自然保护区发展面临的问题之一,优化现有的自然保护区体系是在资源有限的情况下实现自然保护区的保护效益最大化的最佳途径。以岷山地区为主要研究区域,以25种珍稀濒危物种为主要研究对象,通过MAXENT与ZONATION模型模拟,鉴别出岷山地区珍稀濒危物种保护优先区,并提出了自然保护区空间选址的优化方案。研究结果表明,(1)在物种出现点记录较少的情况下,MAXENT模型依然能够比较准确地预测出物种的分布状况;(2)目前建立的保护区对25个物种的平均保护比例为51.8%;(3)通过ZONATION鉴定的优先区总面积为19958.7 km^2,岷山地区现有的29个自然保护区只保护了目标优先区的47.1%,九寨沟中部与南部,平武北部,平武与北川的交界处,北川西北部等地都存在保护空缺。建议在保护空缺的6个地方新建或扩建自然保护区,并在规划时考虑这些区域内部的优先次序。新提出的保护体系能将物种栖息地的保护比例提高至77.9%。研究结果对于岷山及全国其他生物多样性保护关键地区保护体系的规划都具有重要的借鉴意义。 展开更多
关键词 自然保护区 规划 优先区 zonation 岷山
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对于有序聚类程序包ZONATION中几个算法的分析与应用实例 被引量:1
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作者 邢雪 童国榜 林锦璇 《石油实验地质》 CAS CSCD 北大核心 1991年第1期93-98,共6页
本文对有序聚类程序色ZONAION(“分带”)中所用的三种算法(其中两个算法各含两种度量指标)进行了介绍与剖析,并以天津Ⅰ24孔钴井中的孢粉序列分析为例对方法进行了验证。
关键词 有序聚类 程序色 岩芯 zonation
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Liver zonation: Novel aspects of its regulation and its impact on homeostasis 被引量:6
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作者 Rolf Gebhardt Madlen Matz-Soja 《World Journal of Gastroenterology》 SCIE CAS 2014年第26期8491-8504,共14页
Liver zonation, the spatial separation of the immense spectrum of different metabolic pathways along the liver sinusoids, is fundamental for proper functioning of this organ. Recent progress in elucidating localizatio... Liver zonation, the spatial separation of the immense spectrum of different metabolic pathways along the liver sinusoids, is fundamental for proper functioning of this organ. Recent progress in elucidating localization and interactions of different metabolic pathways by using &#x0201c;omics&#x0201d; techniques and novel approaches to couple them with refined spatial resolution and in characterizing novel master regulators of zonation by using transgenic mice has created the basis for a deeper understanding of core mechanisms of zonation and their impact on liver physiology, pathology and metabolic diseases. This review summarizes the fascinating technical achievements for investigating liver zonation and the elucidation of an emerging network of master regulators of zonation that keep the plethora of interrelated and sometimes opposing functions of the liver in balance with nutritional supply and specific requirements of the entire body. In addition, a brief overview is given on newly described zonated functions and novel details on how diverse the segmentation of metabolic zonation may be. From these facts and developments a few fundamental principles are inferred which seem to rule zonation of liver parenchyma. In addition, we identify important questions that still need to be answered as well as interesting fields of research such as the connection of zonation with circadian rhythm and gender dimorphism which need to be pushed further, in order to improve our understanding of metabolic zonation. Finally, an outlook is given on how disturbance of liver zonation and its regulation may impact on liver pathology and the development of metabolic diseases. 展开更多
关键词 HOMEOSTASIS LIVER Metabolic zonation Metabolism Morphogen signalling Optimization Pathology Regulatory network SINUSOID Systems biology
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Geochemical Characteristics and Zonation of Primary Halos of Pulang Porphyry Copper Deposit,Northwestern Yunnan Province,Southwestern China 被引量:12
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作者 陈永清 黄静宁 梁贞 《Journal of China University of Geosciences》 SCIE CSCD 2008年第4期371-377,共7页
The Pulang (普朗) porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian (义敦-中甸) island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large c... The Pulang (普朗) porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian (义敦-中甸) island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large copper deposit. Compared with the composition of granodiorite in China, the porphyry rocks in this area are enriched in W, Mo, Cu, Au, As, Sb, F, V, and Na2O (K1≥1.2). Compared with the composition of fresh porphyry rocks in this district, the mineralized rocks are enriched in Cu, Au, Ag, Mo, Pb, Zn, W, As, Sb, and K2O (K2≥1.2). Some elements show clear anomalies, such as Zn, Ag, Cu, Au, W, and Mo, and can be regarded as pathfinders for prospecting new ore bodies in depth. It has been inferred from factor analysis that the Pulang porphyry copper deposit may have undergone the multiple stages of alteration and mineralization: (a) Cu-Au mineralization; (b) W-Mo mineralization; and (c) silicification and potassic metasomatism in the whole ore-forming process. A detailed zonation sequence of indicator elements is obtained using the variability index of indicator elements as follows: Zn→Ag→Cu→Au→W→Mo. According to this zonation, an index such as (Ag*Zn)D/(Mo×W)D can be constructed and regarded as a significant criterion for predicting the Cu potential at a particular depth. 展开更多
关键词 Pulang porphyry copper deposit zonation of primary halo assessment of Cu potential at depth Tethys-Himalaya ore-forming domain southwestern China
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CIS-Based Mapping and Zonation of Landslide Hazards in Xiaojiang Valley of Southwestern China 被引量:8
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作者 MaZe-zhong HeYi-ping +3 位作者 XieHong CuiPeng ZhongDun-lun JamesS.Gardner 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期1021-1028,共8页
Through the field survey, previous researches and interpretation of aerial photos, a landslide information database of Xiaojiang Valley, Yunnan Province was set up based on the remote sensing (RS) and geographic infor... Through the field survey, previous researches and interpretation of aerial photos, a landslide information database of Xiaojiang Valley, Yunnan Province was set up based on the remote sensing (RS) and geographic information system (GIS) technologies. In the paper, a quantitative model for the landslide hazard assessment and zoning was presented, in which the potential energy could be obtained on basis of thorough analysis of the potential sliding volume, distance and direction of the landslide body. Taking landslide potential energy as the index of the hazard severity zonation, the study area was divided into severe, heavy, medium and light hazard zones. 展开更多
关键词 LANDSLIDE hazard mapping zonation Xiao- jiang Valley southwestern China
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Torrent risk zonation in the Upstream Red River Basin based on GIS 被引量:5
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作者 TANG Chuan ZHU Jing 《Journal of Geographical Sciences》 SCIE CSCD 2006年第4期479-486,共8页
This paper explores the methodology for compiling the torrent hazard and risk zonation map by means of GIS technique for the Red River Basin in Yunnan province of China, where is prone to torrent. Based on a 1:250,00... This paper explores the methodology for compiling the torrent hazard and risk zonation map by means of GIS technique for the Red River Basin in Yunnan province of China, where is prone to torrent. Based on a 1:250,000 scale digital map, six factors including slope angle, rainstorm days, buffer of river channels, maximum runoff discharge of standard area, debris flow distribution density and flood disaster history were analyzed and superimposed to create the torrent risk evaluation map. Population density, farmland percentage, house property, and GDP as indexes accounting for torrent hazards were analyzed in terms of vulnerability mapping. Torrent risk zonation by means of GIS was overlaid on the two data layers of hazard and vulnerability. Then each grid unit with a resolution of 500 m- 500 m was divided into four categories of the risk: extremely high, high, moderate and low. Finally the same level risk was combined into a confirmed zone, which represents torrent risk of the study area. The risk evaluation result in the upper Red River Basin shows that the extremely high risk area of 13,150 km^2 takes up 17.9% of the total inundated area, the high risk area of 33,783 km^2 is 45.9%, the moderate risk area of 18,563 km^2 is 25.2% and the low risk area of 8115 km^2 is 11.0%. 展开更多
关键词 torrent risk zonation GIS the Upstream Red River Basin
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Geoscience landscape division and tourism zonation in the mid-southern section of the Hengduan Mountains, eastern Qinghai-Tibet Plateau 被引量:4
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作者 CHEN Xing SHI Xian-lin 《Journal of Mountain Science》 SCIE CSCD 2018年第4期894-917,共24页
The mid-southern section of the Hengduan Mountains is a typical region of mountainous landscape in western China and is the core region of "Shangri-La", a world-famous ecotourism destination. The landscape c... The mid-southern section of the Hengduan Mountains is a typical region of mountainous landscape in western China and is the core region of "Shangri-La", a world-famous ecotourism destination. The landscape classification system is an important scientific basis for landscape protection and tourism development in this region. By combining geology and geography and referring to the concepts of "system tract" and "tectonic system" in geology, this paper comes up with grading standards for the geoscience landscape system of this region. Based on the regional stratigraphic structure, tectonic fault marks and geomorphological differentiation, this paper comes up with 2 Grade Ⅰ geoscience landscape system tracts, 8 Grade Ⅱ geoscience landscape systems, 21 Grade Ⅲ geoscience landscape areas, and 165 representative Grade Ⅳ geoscience landscape attractions. According to the main classification methods for the geological heritage and tourism landscapes, the geoscience landscapes can be divided into 4 categories, 16 types and 19 subtypes. On this basis, 23 eco-tourism areas of the mid-southern section of the Hengduan Mountains can be delimited. The study provides a theoretical direction and method reference for the geoscience landscape division and tourism zonation, which has an importantsignificance on the mountain landscape protection and tourism development in the regions of complex geo-environments. 展开更多
关键词 Geoseience landscape Landscape system Tourism zonation High mountain canyon area Hengduan Mountains
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Climate warming over 1961–2019 and impacts on permafrost zonation in Northeast China 被引量:4
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作者 Xiaoying Li Huijun Jin +4 位作者 Long Sun Hongwei Wang Ruixia He Yadong Huang Xiaoli Chang 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第3期767-788,共22页
In boreal forest ecosystems, permafrost and forest types are mutually interdependent;permafrost degradation impacts forest ecosystem structure and functions. The Xing’an permafrost in Northeast China is on the southe... In boreal forest ecosystems, permafrost and forest types are mutually interdependent;permafrost degradation impacts forest ecosystem structure and functions. The Xing’an permafrost in Northeast China is on the southern margin of the Eastern Asia latitudinal permafrost body. Under a warming climate, permafrost undergoes rapid and extensive degradation. In this study, the frost-number (Fn) model based on air temperatures and ground surface temperatures was used to predict the distribution of the Xing’an permafrost, and, temporal and spatial changes in air and ground-surface temperatures from 1961 to 2019 are analyzed. The results show that Northeast China has experienced a rapid and substantial climate warming over the past 60 years. The rises in mean annual air and mean annual ground-surface temperatures were higher in permafrost zones than those in the seasonal frost zone. The frost numbers of air and ground-surface temperatures were calculated for determining the southern limit of latitudinal permafrost and for permafrost zonation. The southern limits of discontinuous permafrost, sporadic permafrost, and latitudinal permafrost moved northward significantly. According to the air-temperature frost-number criteria for permafrost zoning, compared with that in the 1960s, the extent of Xing’an permafrost in Northeast China had decreased by 40.6% by the 2010s. With an average rate of increase in mean annual air temperatures at 0.03 ℃ a^(−1), the extent of permafrost in Northeast China will decrease to 26.42 × 10^(4) by 2020, 14.69 × 10^(4) by 2040 and to 11.24 × 10^(4) km^(2) by 2050. According to the ground-surface temperature frost-number criteria, the southern limit of latitudinal permafrost was at the 0.463. From the 1960s to the 2010s, the extent of latitudinal permafrost declined significantly. Due to the nature of the ecosystem-protected Xing’an-Baikal permafrost, management and protection (e.g., more prudent and effective forest fire management and proper logging of forests) of the Xing’an permafrost eco-environment should be strengthened. 展开更多
关键词 Climate warming Permafrost zonation Southern limit of latitudinal permafrost Regional differentiation Mean annual air temperature Mean annual ground surface temperature
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Mineralogical Zonation of Wall-Rock Alteration in Jiaodong Gold Province, North China 被引量:3
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作者 Chen Guangyuan Sun Daisheng Shao Wei Li Shengrong Division of Genetic Mineralogy, China University of Geosciences, Beijing 100083 Fyfe S. William Department of Earth Sciences, University of Western Ontario, London, Ontario, Canada, N6A 5B7 Chen 《Journal of Earth Science》 SCIE CAS CSCD 1999年第1期20-24,共5页
Mineralogical zonation of wall rock alterations in Mesozoic granitoids is summarized from 18 gold deposits in Jiaodong gold province on the Asian mobile continental margin of the west circum Pacific rim. This paper ... Mineralogical zonation of wall rock alterations in Mesozoic granitoids is summarized from 18 gold deposits in Jiaodong gold province on the Asian mobile continental margin of the west circum Pacific rim. This paper deals with wall rock alterations developed around gold mineralizations of the quartz vein type in granitoids and the wall rock alteration type in granitoid basement contacts along Mesozoic fault zones trending mostly NNE SSW and NE SW. Five alteration zones are distinguished from host rock to ore zone, namely the chloritization and sericitization zone, the hematitization rutilization and microclinization zone, the quartz sericitization zone, the pyrite quartz sericitization zone and the pyrite silicification zone. The former two are outer zones marked by incomplete alteration of first mafic and then felsic minerals of the granitoids, while the later three are inner zones marked by complete alteration of both mafic and felsic minerals of the granitoids leading to retrogressive sericitization and progressive silicification with participation of ore elements. The whole process proceeds under dynamometamorphism with high fugacity of volatiles. Wall rock alteration is the intermediate link between unaltered host rock and ore mineralization both in time and space. Development of the alteration zonation and its mineral composition controls genetic type of mineralization, size and grade of the deposit and location of the ore zones. 展开更多
关键词 gold province wall rock alteration zonation mineralogy Jiaodong.
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Saline-alkali land in the Yellow River Delta: amelioration zonation based on GIS 被引量:3
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作者 GUAN Yuan-xiu, LIU Gao-huan, WANG Jin-feng (State Key Laboratory of Resources and Environment Information System, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期313-320,共8页
Soil salinization is one of the major land degradation types and has greatly influenced sustainable agricultural development. Zonation of saline-alkali land is the precondition for effective amelioration. The present ... Soil salinization is one of the major land degradation types and has greatly influenced sustainable agricultural development. Zonation of saline-alkali land is the precondition for effective amelioration. The present situation of saline-alkali land is monitored by remote sensing image processing. Causes for land salinization are analyzed, especially the two key factors, ground water depth and its mineralization degree, are analyzed by using long-term observation data. Previously, zonation of saline-alkali soil was made descriptively and artificially. Based on the present situation of saline-alkali land, ground water depth and ground water mineralization degree, the zonation of saline-alkali land for amelioration in the Yellow River Delta was completed quantitatively. Four different types of saline-alkali land amelioration zones are delineated, namely, easy ameliorated zone, relatively difficult ameliorated zone, difficult ameliorated zone and unfavorable ameliorated zone. Countermeasures for ameliorating saline-alkali soils are put forward according to ecological conditions of different saline-alkali land zones. 展开更多
关键词 GIS the Yellow River Delta saline-alkali land zonation
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Landslide Hazard Zonation Mapping and Comparative Analysis of Hazard Zonation Maps 被引量:3
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作者 S.Sarkar R.Anbalagan 《Journal of Mountain Science》 SCIE CSCD 2008年第3期232-240,共9页
Landslide hazard zonation mapping at regional level of a large area provides a broad trend of landslide potential zones. A macro level landslide hazard zonation for a small area may provide a better insight into the l... Landslide hazard zonation mapping at regional level of a large area provides a broad trend of landslide potential zones. A macro level landslide hazard zonation for a small area may provide a better insight into the landslide hazards. The main objective of the present work was to carry out macro landslide hazard zonation mapping on 1:50,000 scale in an area where regional level zonation mapping was conducted earlier. In the previous work the regional landslide hazard zonation maps of Srinagar-Rudraprayag area of Garhwal Himalaya in the state of Uttarakhand were prepared using subjective and objective approaches. In the present work the landslide hazard zonation mapping at macro level was carried out in a small area using a Landslide Hazard Evaluation Factor rating scheme. The hazard zonation map produced by using this technique classifies the area into relative hazard classes in which the high hazard zones well correspond with high frequency of landslides. The results of this map when compared with the regional zonation maps prepared earlier show that application of the present technique identified more details of the hazard zones, which are broadly shown in the earlier zonation maps. 展开更多
关键词 LANDSLIDES Hazard zonation Garhwal Himalaya MAPPING
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Assessment and Risk Zonation of Landslides in Panxi Area Based on 3S Technology 被引量:3
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作者 ZHANG Baolei SONG Shujun +1 位作者 FENG Wenlan ZHOU Wancun 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期793-800,共8页
Based on field survey located by GPS, it is obtained landslides' location and distribution information by the method of remote sensing in this paper. The vector data of environmental factors that breed and induce lan... Based on field survey located by GPS, it is obtained landslides' location and distribution information by the method of remote sensing in this paper. The vector data of environmental factors that breed and induce landslides such as the elevation, the slope, the vegetation cover, the lithology, the rainfall and so on are gained using GIS(geographical information system) techniques of spatial analysis. All the data obtained are managed through building landslide management system. At the same time, the system is made the platform to appraise the relationship between the distribution of landslides and the environmental factors. The results indicate: landslides take place relatively easily in the slope range between 10° and 25°; most landslides are in the mixed area of bush and grass with a coverage degree of from 20° to 65°; the distribution of landslides has a positive relationship with the distribution of annual rainfall. The risk degree of Panxi Area is zoned and mapped by the model of liner stack using GIS technique, and the result indicates: the place of high risk degree is the belt of Panzhihua-Miyi-Dechang-Mugu and southeast of Huili county and Huidong county,and area is about 512 707 hm^2. 展开更多
关键词 LANDSLIDE 3S technology risk zonation Panxi Area
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