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Discovery and features of vertical zonations of tidal salt-marsh foraminifera in Jianchuan, North Jiangsu Province, China
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作者 尤坤元 张兆干 +1 位作者 吴小根 施炳文 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第1期87-94,共8页
Through densified surface sampling of foraminifera and accurate elevation measurement a-long three transect lines in open-coast tidal salt-marsh of Jianchuan, particular salt-marsh foraminifera assemblages were found.... Through densified surface sampling of foraminifera and accurate elevation measurement a-long three transect lines in open-coast tidal salt-marsh of Jianchuan, particular salt-marsh foraminifera assemblages were found. The salt-marsh foraminifera assemblages are distributed in well-defined vertical zonations with respect to elevation and closely parallel marsh floral zonations. At the top of the vertical zonation all foraminifera disappear abruptly which are accurately located at the highest high water datum. This distribution pattern can be used to relocate former sea levels accurately (to an accuracy of within ±5 cm). A modern regional criterion of foraminifera for relocating the former sea levels in high resolution in our country is provided, and deficiencies of studying the vertical zonation only in sheltered coast salt-marsh abroad are filled up. 展开更多
关键词 Jianchuan of North Jiangsu Province open-coast tidal salt-marsh vertical zonation of foraminifera high resolution criterion for former sea levels
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Quantitative characterization of vertical zonation of Mesozoic granite weathering reservoirs in the coastal area of eastern Fujian Province,China
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作者 Jing-Song Hu Yi-Ming Jiang +3 位作者 Hua-Feng Tang Wen-Rui Ma Peng Tao Ning-Yuan Sun 《Petroleum Science》 SCIE EI CSCD 2023年第5期2664-2682,共19页
Weathering crust reservoirs have obvious vertical zonation,which is the focus of weathering crust reservoir research,but there is a lack of quantitative characterization indexes.To achieve the quantitative characteriz... Weathering crust reservoirs have obvious vertical zonation,which is the focus of weathering crust reservoir research,but there is a lack of quantitative characterization indexes.To achieve the quantitative characterization of granite weathering crust reservoir and provide the basis for oil exploration of granite weathering crust buried hill reservoir,in this paper,the vertical zonation of granite weathering crust reservoir is quantitatively divided by testing and analyzing the uniaxial compressive strength(UCS),magnetic susceptibility(MS),permeability,and chemical index of alteration(CIA)of the Mesozoic granite weathering crust in the coastal area of eastern Fujian.The results show that the granite weathering crust reservoir can be divided into four zones vertically:a soil zone(SZ),weathered and dissolved zone(WDZ),fracture zone(FZ),and bedrock zone(BZ).A cataclastic area is developed in the FZ and BZ,in which structural fractures are well-developed,the fracture surface density is usually greater than 200 m/m^(2),and the contribution to the fractures in the rock mass is up to about 50%,making this the sweet spot of the reservoir.In the SZ,the rocks are loose,and the pores are well-developed.The UCS is less than 10 MPa,and the average rate of change of the UCS(Δ_(σ))is 0.90.The average permeability is 2823.00 mD,and the average rate of change of the permeability(Δ_(κ))is 5.13.The average CIA is 74.9%.The average clay mineral content is 7%.The rocks in the WDZ have been significantly weathered by physical and chemical processes,and the weathering fractures and dissolution pores are well-developed.The average UCS is 18.2 MPa,and the averageΔ_(σ)is 0.70.The average permeability is 143.80 mD,and averageΔ_(κ)is 4.17.The average CIA is 65.3%.The average clay mineral content is 4%.Under the influence of tectonic movement and physical weathering,the rocks in the FZ have developed structural fractures and a few weathered fractures.The average UCS is 57.9 MPa,and the averageΔ_(σ)is 0.18.The average permeability is 5.50 mD,and the averageΔ_(κ)is 2.55.The average CIA is 61.6%.The average clay mineral content is 2%.In the BZ,the rocks are intact and hard.The average UCS is 69.9 MPa,and the average Ds is 0.13.The average permeability is 1.46 mD,and the averageΔ_(κ)is 1.43.The average CIA is 57.8%.The average clay mineral content is less than 1%.The multi-parameter combination of the UCS,Δ_(σ),permeability,Δ_(κ),CIA,and clay mineral content achieved good results in the division of the zones of the weathering crust.The UCS increases gradually from top to bottom,while Ds,permeability,Δ_(κ),CIA,and clay mineral content all decrease gradually.In addition,based on the petrophysical parameters of the rocks,including the density,resistivity,and acoustic velocity,a good division effect was also achieved,which can provide a basis for the vertical zonation of the granite buried-hill weathering crust reservoir. 展开更多
关键词 Granite weathering crust Vertical zonation of reservoir Quantitative characterization Eastern Fujian Mesozoic granite
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Research progress in the efficacy of deep brain stimulation with different targets in Parkinson's disease
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作者 AI Xiang-bai HUANG Xiao-gan +2 位作者 WANG Yi-tian LI Jun-ju ZHAO Jian-nong 《Journal of Hainan Medical University》 CAS 2023年第21期53-59,共7页
Parkinson's disease(PD)is a chronic progressive neurodegenerative disease.Deep brain stimulation(DBS)is an effective treatment for patients with advanced PD.There are many DBS targets for PD,including subthalamic ... Parkinson's disease(PD)is a chronic progressive neurodegenerative disease.Deep brain stimulation(DBS)is an effective treatment for patients with advanced PD.There are many DBS targets for PD,including subthalamic nucleus(STN),globus pallidus(GPi),meso-ventral thalamic nucleus(VIM),pontine peduncle nucleus(PPN),posterior subthalamic region(PSA)and zonation of undetermined zone(ZI).This paper summarizes the efficacy of each target in the treatment of PD with DBS,not only makes a systematic analysis and comparison of motor symptoms,but also makes a detailed description of the efficacy of non-motor symptoms,so as to provide a personalized treatment basis for PD patients to select appropriate target targets in DBS. 展开更多
关键词 Parkinson's disease Deep brain stimulation Subthalamic nucleus Globus pallidus Ventral thalamic nucleus Pontine peduncle nucleus Posterior subthalamic areas Zonation of undetermined zone
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基于MAXENT和ZONATION的加拿大一枝黄花入侵重点监控区确定 被引量:34
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作者 李丽鹤 刘会玉 +2 位作者 林振山 贾俊鹤 刘翔 《生态学报》 CAS CSCD 北大核心 2017年第9期3124-3132,共9页
外来入侵植物对本地生态系统及其生物多样性构成严重的威胁,要有效地控制外来植物入侵,首先应该明确植物入侵的高度风险区.以加拿大一枝黄花(Solidago canadensis)为对象,以其广泛发生的安徽、江苏、浙江和上海华东3省1市为研究区域,综... 外来入侵植物对本地生态系统及其生物多样性构成严重的威胁,要有效地控制外来植物入侵,首先应该明确植物入侵的高度风险区.以加拿大一枝黄花(Solidago canadensis)为对象,以其广泛发生的安徽、江苏、浙江和上海华东3省1市为研究区域,综合考虑了土地利用变化、人类活动干扰、土壤性质、气候和地形等影响因子,采用MAXENT模型预测其潜在分布及其对主要影响因子的响应,并结合空间优化软件ZONATION识别出需要重点布控的入侵风险区。结果表明:1)影响加拿大一枝黄花分布的主要环境因子及其百分比贡献率分别为:距主要道路距离(29.4%)、土地利用变化(16.9%)、降水的季节性变异(15.9%)、人口密度(9.5%)与最干季均温(6.2%)。2)从影响因子的响应曲线分析得出,加拿大一枝黄花的发生概率随着距主要道路距离的增大而迅速减小;在耕地转化成的城乡居民点及工矿用地、水域转化成的草地、城乡居民点及工矿用地转化成的林地、草地与城乡居民点及工矿用地相互转换频繁的区域和城乡居民点及工矿用地保持不变的区域,其发生概率明显较高;其发生概率随着降水季节性变异的增大而快速减小至0.4,之后缓慢减小;随着人口密度的增大,其发生概率起初急剧升高,人口密度超过4千人/km^2后又缓慢地小幅下降;随着最干季均温的增大,其发生概率逐渐减小,在2.4℃附近达最小,之后逐渐增大。3)加拿大一枝黄花的入侵风险区面积为130433 km^2。其中,一级风险区主要分布在太湖流域、沿杭州湾地区、浙江沿海以及内陆地势较低的耕地及居民点区域;二级风险区主要分布在一级风险区的外缘,尤其是江苏南部的长江沿岸地区。三级风险区则广泛分布在江苏的南部和东部,安徽的中东部,浙江的北部和东部。 展开更多
关键词 加拿大一枝黄花 MAXENT 风险预测 响应 ZONATION
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基于ZONATION的岷山山系多物种保护规划 被引量:11
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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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Conodont Biostratigraphy of the Middle Cambrian through Lowermost Ordovician in Hunan, South China 被引量:29
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作者 DONGXiping JohnE.REPETSKI StigM.BERGSTR(OE)M 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第6期1185-1206,共22页
Since 1985, samples with a total weight of more than 14,000 kg, mainly from three key sections in western and northwestern Hunan, South China, have been processed for conodonts. In strata older than the late Late Camb... Since 1985, samples with a total weight of more than 14,000 kg, mainly from three key sections in western and northwestern Hunan, South China, have been processed for conodonts. In strata older than the late Late Cambrian paraconodonts have proved useful for stratigraphic subdivision and correlation. Thirteen conodont zones are proposed in the Middle Cambrian through lowermost Ordovician. The correlation between these zones and those of North China, western U. S.A., western Newfoundland, Canada, and Iran is discussed. In ascending order, these 13 zones are as follows: The Gapparodus bisulcatus-Westergaardodina brevidens Zone, Shandongodus priscus-Hunanognathus tricuspidatus Zone, Westergaardodina quadrata Zone, Westergaardodina matsushitai-W. grandidens Zone, Westergaardodina lui-W. am Zone, Westergaardodina cf. calix-Prooneotodus rotundatus Zone, Proconodontus tenuiserratus Zone, Proconodontus Zone, Eoconodontus Zone, Cordylodus proavus Zone, Cordylodus intermedius Zone, Cordylodus lindstromi Zone, and Cordylodus angulatus Zone (lower part). The Westergaardodina lui-W. ani and Westergaardodina cf. calix-Prooneotodus rotundatus Zones replace the Westergaardodina proligula and Westergaardodina cf. behrae-Prooneotodus rotundatus Zones, respectively, in the lowermost Upper Cambrian. Two new species (Westergaardodina Iui and Westergaardodina ani) and one conditionally identified species (Westergaardodina cf. calix) are described. 展开更多
关键词 conodont zonation Middle and Upper Cambrian lowermost Ordovician HUNAN South China.
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Forest fire risk assessment in parts of Northeast India using geospatial tools 被引量:7
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作者 Kanchan Puri G. Areendran +2 位作者 Krishna Raj Sraboni Mazumdar P.K. Joshi 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第4期641-647,共7页
Forest fire is a major cause of changes in forest structure and function. Among various floristic regions, the northeast region of India suffers maximum from the fires due to age-old practice of shifting cultivation a... Forest fire is a major cause of changes in forest structure and function. Among various floristic regions, the northeast region of India suffers maximum from the fires due to age-old practice of shifting cultivation and spread of fires from jhum fields. For proper mitigation and management, an early warning of forest fires through risk modeling is required. The study results demonstrate the potential use of remote sensing and Geographic Information System (GIS) in identifying forest fire prone areas in Manipur, southeastern part of Northeast India. Land use land cover (LULC), vegetation type, Digital elevation model (DEM), slope, aspect and proximity to roads and settlements, factors that influence the behavior of fire, were used to model the forest fire risk zones. Each class of the layers was given weight according to their fire inducing capability and their sensitivity to fire. Weighted sum modeling and ISODATA clustering was used to classify the fire zones. TO validate the results, Along Track Scanning Radiometer (ATSR), the historical fire hotspots data was used to check the occurrence points and modeled forest fire locations. The forest risk zone map has 55-63% of agreement with ATSR dataset. 展开更多
关键词 ATSR forest fire modeling risk zonation WEIGHTS MANIPUR
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Differential Tectonic Deformation of the Longmen Mountain Thrust Belt,Western Sichuan Basin,China 被引量:6
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作者 TANG Liangjie YANG Keming +3 位作者 JIN Wenzheng WAN Guimei LüZhizhou YU Yixin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第1期158-169,共12页
Field investigation and seismic section explanation showed that the Longmen Mountain Thrust Belt has obvious differential deformation: zonation, segmentation and stratification. Zonation means that, from NW to NE, th... Field investigation and seismic section explanation showed that the Longmen Mountain Thrust Belt has obvious differential deformation: zonation, segmentation and stratification. Zonation means that, from NW to NE, the Longmen Mountain Thrust Belt can be divided into the Songpan- Garz~ Tectonic Belt, ductile deformation belt, base involved thrust belt, frontal fold-thrust belt, and foreland depression. Segmentation means that it can be divided into five segments from north to south: the northern segment, the Anxian Transfer Zone, the center segment, the Guanxian Transfer Zone and the southern segment. Stratification means that the detachment layers partition the structural styles in profile. The detachment layers in the Longmen Mountain Thrust Belt can be classified into three categories: the deep-level detachment layers, including the crust-mantle system detachment layer, intracrustal detachment layer, and Presinian system basal detachment layer; the middle-level detachment layers, including Cambrian-Ordovician detachment layer, Silurian detachment layer, etc.; and shallow-level detachment layers, including Upper Triassic Xujiahe Formation detachment layer and the Jurassic detachment layers. The multi-level detachment layers have a very important effect on the shaping and evolution of Longmen Mountain Thrust Belt. 展开更多
关键词 differential deformation detachment layer segmentation STRATIFICATION transfer zone zonation Longmen Mountain Thrust Belt
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CIS-Based Mapping and Zonation of Landslide Hazards in Xiaojiang Valley of Southwestern China 被引量:7
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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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厦门市重点保护植物空间优先保护格局研究 被引量:6
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作者 钱灵颖 黄智洵 +1 位作者 杨盛昌 曹文志 《生态学报》 CAS CSCD 北大核心 2021年第11期4367-4378,共12页
生物多样性保护对维持城市生态系统功能具有重要意义。以39种厦门市重点保护植物为对象,通过物种分布模型MaxENT获得物种潜在分布栅格图,利用空间保护优先化定量工具Zonation软件识别理论上既适宜重点保护植物生存又能够保证景观连通性... 生物多样性保护对维持城市生态系统功能具有重要意义。以39种厦门市重点保护植物为对象,通过物种分布模型MaxENT获得物种潜在分布栅格图,利用空间保护优先化定量工具Zonation软件识别理论上既适宜重点保护植物生存又能够保证景观连通性的区域,获得本地重点保护植物景观保护等级。根据2020年全球生物多样性目标,将景观保护等级最高的17%区域视为多物种空间优先保护区,结合Zonation模型生成的随景观丧失物种加权灭绝风险曲线,将保护等级最高的8%区域划为一级保护区,保护等级在8%—17%范围内的区域划为二级保护区。利用MaxENT模型中的jackknife刀切法发现海拔是对本地重点保护植物分布影响最大的环境因子,优先保护区集中分布于海拔较低的海岸带区域。将优先保护区与自然保护地建设现状、厦门市生态功能区规划、土地利用规划、城市总体规划对比发现厦门市岛外西部、北部的优先保护区得到了较好保护;岛外的西南部及东南部、岛内的东部及南部海岸带的优先保护区被建设用地大规模占用,已纳入自然保护地范围的区域较少,存在大量的海岸带优先保护区保护空缺;岛外东南部的部分优先保护区虽未被占用,但规划中属发展备用地,缺乏生态保护。为避免优先保护区面积的进一步萎缩,应重点关注海岸带区域优先保护区的生态保护,将目前属于发展备用地的优先保护区转划为生态留白空间,针对一级、二级优先保护区分别实施刚性和弹性的生态保育措施,在保护生物多样性的同时,严控对海岸带区域优先保护区的进一步开发利用,协调优先保护区内保护与开发利用间的关系。 展开更多
关键词 ZONATION MAXENT 生物多样性 优先保护
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Geochemical Characteristics and Zonation of Primary Halos of Pulang Porphyry Copper Deposit,Northwestern Yunnan Province,Southwestern China 被引量:11
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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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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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Groundwater regime and calculation of yield response in North China Plain: a case study of Luancheng County in Hebei Province 被引量:5
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作者 Jia Jin-sheng Yu Jing-jie Liu Chang-ming 《Journal of Geographical Sciences》 SCIE CSCD 2002年第2期94-102,共9页
The groundwater table has been declining at a rate of 0.65 m/yr in Luancheng County since large scale groundwater extraction carried out in the 1960s. The drop of precipitation, substantial increase in agricultural ou... The groundwater table has been declining at a rate of 0.65 m/yr in Luancheng County since large scale groundwater extraction carried out in the 1960s. The drop of precipitation, substantial increase in agricultural output, variations of crop planting structure and construction of water conservancy projects in the headwater area all tie up with the decline of the groundwater table. On the basis of analyzing the hydrogeological conditions and the water resources utilization of Luancheng County, a three-dimensional groundwater flow model was developed to simulate the county抯 groundwater flow through finite-difference method using Visual Modflow software. We divide the research field into four parts after analyzing the hydrogeological condition. Based on parameter calibration and adjustment using measured data, the hydraulic conductivity and specific yield were simulated. Using the calibrated model, we analyze the agricultural water saving potentiality and its influence on the groundwater. The results are as follows: (1) if we decrease the amount of water extracted by 0.14×108 m3, the average groundwater table of the five observation wells in December will rise by 0.33 m; (2) if we decrease the water by 0.29×108 m3, the average groundwater table of the five observation wells in December will rise by 0.64 m; and (3) if we increase the water by 0.29×108 m3, the average groundwater table of the five observation wells in December will decline by 0.45 m. So we can draw a conclusion that controlling the agricultural water use is an important way to prevent the decline of groundwater table. 展开更多
关键词 groundwater table Visual Modflow zonation of the hydrogeological parameters groundwater simulation model groundwater exploitation
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Liver zonation: Novel aspects of its regulation and its impact on homeostasis 被引量:3
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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 localization a... 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"omics"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 Mo
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Ecophysiological characteristics of four intertidal marine macroalgae during emersion along Shantou coast of China,with a special reference to the relationship of photosynthesis and CO_(2) 被引量:3
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作者 ZOUDinghui GAOKunshan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第3期105-113,共9页
Intertidal marine macroalgae experience periodical exposures during low tide due to their zonational distribution. The duration of such emersion leads to different exposures of the plants to light and aerial CO2, whic... Intertidal marine macroalgae experience periodical exposures during low tide due to their zonational distribution. The duration of such emersion leads to different exposures of the plants to light and aerial CO2, which then affect the physiology of them to different extents. The ecophysiological responses to light and CO2 were investigated during emersion in two red algae Gloiopeltis furcata and Gigartina intermedia, and two brown algae Petalonia fascia and Sargassum hemiphyllum, growing along the Shantou coast of China. The light-saturated net photosynthesis in G. furcata and P. fascia showed an increase followed by slightly desiccation, whereas that in G. intermedia and S. hemiphyllumexhibited a continuous decrease with water loss. In addition, the upper-zonated G. furcata and P. fascia, exhibited higher photosynthetic tolerance to desiccation and required higher light level to saturate their photosynthesis than the lower-zonated G. intermedia and S. hemiphyllum. Desiccation had less effect on dark respiration in these four algae compared with photosynthesis. The light-saturated net photosynthesis increased with increased CO2 concentrations, being saturated at CO2 concentrations higher than the present atmospheric level in G. furcata, G. intermedia and S. hemiphyllum during emersion. It was evident that the relative enhancement of photosynthesis by elevated CO2 in those three algae increased, though the absolute values of photosynthetic enhancement owing to CO2 increase were reduced when the desiccation statuses became more severe. However, in the case of desiccated P. fascia (water loss being greater than 20 %), light saturated net photosynthesis was saturated with current ambient atmospheric CO2 level. It is proposed that increasing atmospheric CO2 will enhance the daily photosynthetic production in intertidal macroalgae by varied extents that were related to the species and zonation. 展开更多
关键词 marine macroalgae ECOPHYSIOLOGY PHOTOSYNTHESIS CO2 ZONATION
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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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Dimensions of hepatocellular carcinoma phenotypic diversity 被引量:4
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作者 Romain Désert Natalia Nieto Orlando Musso 《World Journal of Gastroenterology》 SCIE CAS 2018年第40期4536-4547,共12页
Hepatocellular carcinoma(HCC) is the 3^(rd) leading cause of cancer-related death worldwide. More than 80% of HCCs arise within chronic liver disease resulting from viral hepatitis, alcohol, hemochromatosis, obesity a... Hepatocellular carcinoma(HCC) is the 3^(rd) leading cause of cancer-related death worldwide. More than 80% of HCCs arise within chronic liver disease resulting from viral hepatitis, alcohol, hemochromatosis, obesity and metabolic syndrome or genotoxins. Projections based on Western lifestyle and its metabolic consequences anticipate a further increase in incidence, despite recent breakthroughs in the management of viral hepatitis. HCCs display high heterogeneity of molecular phenotypes, which challenges clinical management. However, emerging molecular classifications of HCCs have not yet formed a unified corpus translatable to the clinical practice. Thus, patient management is currently based upon tumor number, size, vascular invasion, performance status and functional liver reserve. Nonetheless, an impressive body of molecular evidence emerged within the last 20 years and is becoming increasingly available to medical practitioners and researchers in the form of repositories. Therefore, the aim this work is to review molecular data underlying HCC classifications and to organize this corpus into the major dimensions explaining HCC phenotypic diversity. Major efforts have been recently made worldwide toward a unifying "clinically-friendly" molecular landscape. As a result, a consensus emerges on three major dimensions explaining the HCC heterogeneity. In the first dimension, tumor cell proliferation and differentiation enabled allocation of HCCs to two major classes presenting profoundly different clinical aggressiveness. In the second dimension, HCC microenvironment and tumor immunity underlie recent therapeutic breakthroughs prolonging patients' survival. In the third dimension,metabolic reprogramming, with the recent emergence of subclass-specific metabolic profiles, may lead to adaptive and combined therapeutic approaches. Therefore, here we review recent molecular evidence, their impact on tumor histopathological features and clinical behavior and highlight the remaining challenges to translate our cognitive corpus into patient diagnosis and allocation to therapeutic options. 展开更多
关键词 Liver metabolism Liver zonation Hepatocellular carcinoma classification WNT/Β-CATENIN TP53 Tumor microenvironment Inflammation Tumor immunity Hepatocyte proliferation Hepatocyte differentiation
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Landslide Hazard and Risk Assessment on the Northern Slope of Mt. Changbai, China 被引量:3
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作者 LIU Zhenghua ZHANG Yanbin +1 位作者 Yoshiharu ISHIKAWA Hiroyuki NAKAMURA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第1期214-224,共11页
Landslide hazard and risk assessment on the northern slope of Mt. Changbai, a well-known tourist attraction near the North Korean-Chinese border, are assessed. This study is divided into two parts, namely, landslide h... Landslide hazard and risk assessment on the northern slope of Mt. Changbai, a well-known tourist attraction near the North Korean-Chinese border, are assessed. This study is divided into two parts, namely, landslide hazard zonation and risk assessment. The 1992 Anbalagan and Singh method of landslide hazard zonation (LHZ) was modified and used in this area. In this way, an Associative Analysis Method was used in representative areas to get a measure for controlling factors (slope gradient, relative relief, vegetation, geology, discontinuity development, weak layer thickness and ground water). For the membership degree of factor to slope failure, the middle range of limited values was used to calculate LHZ. Based on an estimation of the potential damage from slope failure, a reasonable risk assessment map was obtained using the relationship of potential damage and probable hazard to aid future planning and prediction and to avert loss of life. 展开更多
关键词 Landslide Hazard Zonation (LHZ) controlling factor Associative Analysis Method membership degree risk assessment TOURISM China
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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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