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Role of lithology, weathering and precipitation on water chemistry of lakes from Larsemann Hills and Schirmacher Oasis of East Antarctica 被引量:1
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作者 Rajesh ASTHANA Prakash K SHRIVASTAVA +3 位作者 Hari B SRIVASTAVA Ashit K SWAIN Mirza Javed BEG Amit DHARWADKAR 《Advances in Polar Science》 CSCD 2019年第1期35-51,共17页
Schirmacher Oasis and Larsemann Hills areas represent two different periglacial environments of East Antarctica. Schirmacher Oasis is characterized by a vast stretch of ice-shelf in the north and East Antarctic Ice Sh... Schirmacher Oasis and Larsemann Hills areas represent two different periglacial environments of East Antarctica. Schirmacher Oasis is characterized by a vast stretch of ice-shelf in the north and East Antarctic Ice Sheet(EAIS) to its south. Whereas, in Larsemann Hills area the northern and north-western boundary is coastal area and EAIS in the southern part,exhibiting polar lowland between the marine and continental glacial ecosystems. Physico-chemical parameters of water samples from different lakes of both of these two distinct locations are quite contrasting and have indicated influence of lithology, weathering, evaporation and precipitation. The lake water chemistry in Larsemann Hills area is mainly governed by the lithology of the area while Schirmacher lakes exhibit influence of precipitation and rock composition. All major ions of lake waters indicate balanced ionic concentrations. The atmospheric precipitation has significantly modified the ionic distributions in the lakes and channels. Carbonation is the main proton supplying geochemical reactions involved in the rock weathering and this is an important mechanism which controls the hydrochemistry. The lake water hydrochemistry differs widely not only between two distant periglacial zones but also within a short distance of a single periglacial entity, indicating influence of territorial climate over hydrochemistry. 展开更多
关键词 lake water IONIC concentration Schirmacher OASIS Larsemann hills East ANTARCTICA
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On the organic compounds in water of Mochou Lake and Heart Lake in Larsemann Hills,Antarctica
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作者 李植生 陈旭东 +3 位作者 张银华 梁小民 王骥 梁彦龄 《Chinese Journal of Polar Science》 1997年第2期45-56,共12页
Information on the organic compounds in water of Mochou Lake and Heart Lake, Antarctica is given in this paper. 93 organic compounds were identified from 121 chemical constituents in lake water, including n alkanes,... Information on the organic compounds in water of Mochou Lake and Heart Lake, Antarctica is given in this paper. 93 organic compounds were identified from 121 chemical constituents in lake water, including n alkanes, lipidal isopentadienes, aromatic hydrocarbons, polycyclic aromatics, alcohols, aldehydes, ketones, esters, monocarboxylic acids and phthalic esters in the range of 0.0274.79 μg/L. Organic compounds of global occurrence like BHC, DDT and PCBs were detected in the water, at the concentration of 0.0120.356 μg/L. 展开更多
关键词 Larsemann hills Mochou lake Heart lake organic compounds global pollutants.
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Reconstruction Design of Zaozhuang Gangue Hill Based on the Interaction of“Scenery”and“View”
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作者 CAO Ying LIANG Zhiwei ZHANG Li 《Journal of Landscape Research》 2023年第4期9-16,共8页
Gangue hill is the associated accumulation landscape of long-term coal mining.There are a large number of gangue hills left in coal mining cities,which not only causes ecological damage but also affects the urban envi... Gangue hill is the associated accumulation landscape of long-term coal mining.There are a large number of gangue hills left in coal mining cities,which not only causes ecological damage but also affects the urban environment,thus becoming the focus of urban landscape transformation of coal mining cities.With the increase of people’s demand for ecological leisure,it has become the first choice to transform gangue hill and its surrounding areas into community parks.From the perspective of urban space and landscape system,as a huge regeneration landform in the city and a unique landscape in the mining area,gangue hill not only needs to be afforested,but also needs to be connected with mining heritages and landscape nodes in the city to form the interaction between“scenery”and“view”,so as to form an integrated mining cultural landscape system at the urban level.On the basis of this concept,taking the gangue hill of Zhongxing in Zaozhuang City as an example,this paper quantitatively analyzes the best landscape construction site in the gangue hill via viewshed analysis in GIS.Through this method,the gangue hill and Zhongxing mining heritage are closely combined,so as to establish the interactive relationship between“scenery”and“view”.It can guide the planning and design of sightseeing route and footpath system,and also provide a technical support for the design of community parks transformed from gangue hills. 展开更多
关键词 Gangue hill Zhongxing mining heritage Interaction of“scenery”andview viewshed analysis
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The Formation of the Qarhan Saline Lakes as Viewed in the Light of Neotectonic Movement 被引量:3
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作者 Zhu Yunchu Li Zhengyan +1 位作者 Wu Bihao Wang Mili Research Institute of Exploration and Development of Saline Lakes, Golmud, Qinghai Institute of Mineral Deposits, CAGS Jia Zhongpeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1990年第3期247-259,共13页
Investigations on stratigraphy, geomorphology and neotectonic movement in the Eastern Kunlun Moun-tains show that there existed a series of ancient lakes, including some saline lakes. in the studied region about30,000... Investigations on stratigraphy, geomorphology and neotectonic movement in the Eastern Kunlun Moun-tains show that there existed a series of ancient lakes, including some saline lakes. in the studied region about30,000 years ago, They were distributed south of the middle Kunlun fault. from the middle-upper reaches of thepresent Narin Gol River in the west to the Alag Lake-Tosou Lake in the east. Of these the ancient Narin GolLake and Kunlun Lake were mainly recharged by the hot water related to valcanos. so the B, Li and K con-tents are relatively high. The neotectonic movement that commenced at 30.000 a B.P. caused the river system in the EasternKunlun Mountains to invade southwards. as a result the ancient lake water was captured to recharge theQarhan area. Therefore, the hot springs related to recent volcanism and faulting on the southern bank of theupper reaches of the Narin Gol River became an important source of saline materials for the Qarhan Lake. 展开更多
关键词 the Formation of the Qarhan Saline lakes as viewed in the Light of Neotectonic Movement lake
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Etsuko’s Pursuit of Identity:An Interpretation of A Pale View of Hills from the Perspective of Spatial Criticism
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作者 HU Sheng-hao 《Journal of Literature and Art Studies》 2020年第10期873-879,共7页
On the basis of Etsuko’s memory,A Pale View of Hills,a masterpiece of Kazuo Ishiguro,narrates Etsuko’s life experiences and her identity construction.The paper analyses the novel from the perspective of spatial crit... On the basis of Etsuko’s memory,A Pale View of Hills,a masterpiece of Kazuo Ishiguro,narrates Etsuko’s life experiences and her identity construction.The paper analyses the novel from the perspective of spatial criticism proposed by Edward Soja and explores the three-dimensional spaces constructed in the novel in order to explore Etsuko’s attempts to leave the marginal space and analyse her pursuit of identity.The paper comes to the conclusion that by constructing Thirdspace open to all cultures,Etsuko eliminates the dichotomy between Firstspace and Secondspace and embraces her hybrid identity. 展开更多
关键词 Kazuo Ishiguro A Pale view of hills spatial criticism
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Water quality of Kaptai reservoir in Chittagong Hill Tracts of Bangladesh 被引量:2
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作者 Shyamal Karmakar S. M. Sirajul Haque +1 位作者 M. Mozaffar Hossain M. Shafiq 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第1期87-92,共6页
A study was conducted in Kaptai reservoir, one of the largest man-made freshwater lakes of South-east Asia, to determine present status of water quality and its suitability for fishing and other uses. Water samplings ... A study was conducted in Kaptai reservoir, one of the largest man-made freshwater lakes of South-east Asia, to determine present status of water quality and its suitability for fishing and other uses. Water samplings were from middle part of the reservoir at 0.2 and 0.8 fractional depths at five different locations from upstream to downstream viz. Burburichara, Maichchari, Subolong, Basanthakum, and Rangamati. Water analyses show that concentrations of NO3-N, K+ and total P, and suspended solid at all the sampling stations were beyond the recommended values for fish culture. Concentrations of Na^+, Ca^2+, Mg^2+, SO4^2-, Cl^-, total dissolved solid (TDS), dissolved oxygen (DO) and chemical oxygen demand (COD) were within the standards for aquaculture. Concentrations of NO3-N, SO4^2-, K+ and total P showed no definite trend with depths, locations as well as rainy and dry seasons. Water pH, conductivity, Na^+ and HCO3- contents were lower in rainy season, and DO and COD higher at almost all the locations in both the depths, compared with dry season. Total solids and concentrations of TDS, DO, COD, Ca^2+, Mg^2+ and Na^+ were higher in upstream and decreased gradually towards downstream in the reservoir. Concentrations of DO and Ca2+ and pH were higher and Mg2+ less at 0.2-fractional depth than those at 0.8-fractional depth at almost all the locations. The reservoir is in mesotrophic condition containing high concentration of NO3-N and total P, in alarming status with the presence of excessive suspended solids from urban pollution around the town. It is necessary to adopt measures for protecting water quality in the reservoir due to such deteriorations. 展开更多
关键词 Karnaphuli river lake water quality Chittagong hill Tract
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Environmental evolution of Xingkai (Khanka) Lake since 200 ka by OSL dating of sand hills 被引量:1
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作者 ZHU Yun SHEN Ji +1 位作者 LEI GuoLiang WANG Yong 《Chinese Science Bulletin》 SCIE EI CAS 2011年第24期2604-2612,共9页
Crossing the Sino-Russian boundary, Xingkai Lake is the largest freshwater lake in Northeast Asia. In addition to the lakeshore, there are four sand hills on the north side of the lake that accumulated during a period... Crossing the Sino-Russian boundary, Xingkai Lake is the largest freshwater lake in Northeast Asia. In addition to the lakeshore, there are four sand hills on the north side of the lake that accumulated during a period of sustainable and stable lacustrine trans gression and were preserved after depression. Analysis of well-dated stratigraphic sequences based on 18 OSL datings combined with multiple index analysis of six sites in the sand hills revealed that the north shoreline of Xingkai Lake retreated in a stepwise fashion since the middle Pleistocene, and that at least four transgressions (during 193-183 ka, 136-130 ka, 24-15 ka and since 3 ka) and three depressions occurred during this process. The results of this study confirmed that transgressive stages were concur- rent with epochs of climate cooling, whereas the period of regression corresponded to the climatic optima. Transgressions and regressions were primarily caused by variations in the intensity of alluvial accumulation in the Ussuri River Valley and fluctuations in regional temperature and humidity that were controlled by climatic change. Moreover, one obvious transgressive process that occurred in MIS3 may have been related to enhanced precipitation that was reportedly widespread in the west of China, while shortterm fluctuations in the lake level might well be a direct response to regional precipitation variations on the millennial scale. 展开更多
关键词 光释光测年 兴凯湖 环境演变 乌苏里江流域 气候变冷 回归分析 东北亚地区 多指标分析
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战争记忆与历史书写--论石黑一雄日本二战题材小说
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作者 刘利平 《外国语文研究(辑刊)》 2024年第2期78-88,共11页
以记忆书写历史是石黑一雄小说中最为突出的主题之一。在他的小说中,个体经历往往以回忆的形式展开,这些个体记忆一方面极具个人化和私密化色彩,另一方面又融进了很多公共历史化因素。因此,个体经历被作家从私人化领域提升至公共意识层... 以记忆书写历史是石黑一雄小说中最为突出的主题之一。在他的小说中,个体经历往往以回忆的形式展开,这些个体记忆一方面极具个人化和私密化色彩,另一方面又融进了很多公共历史化因素。因此,个体经历被作家从私人化领域提升至公共意识层面,记忆与历史书写之间的关系成为揭示历史本质的途径之一。《远山淡影》、《浮世画家》和《上海孤儿》构成了石黑一雄日本战争历史记忆化书写的三个阶段,隐藏在《远山淡影》中的战争记忆,经过了《浮世画家》的自我修正,最终在《上海孤儿》中呈现出历史的真相。而小说家石黑一雄,正是借助这种以记忆书写历史的方式,对人们在战争中所遭受到的创伤,对于日本二战的历史真相不断进行增补,通过文本的留白、压抑和矛盾,在记忆的缝隙中,呈现出过去若隐若现、无由确定的真相。 展开更多
关键词 战争记忆 历史书写 《远山淡影》 《浮世画家》 《上海孤儿》
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鄱阳湖北部沙山一处平行层理砂层的释光信号回零分析及年代学研究
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作者 钟文 龚志军 +2 位作者 罗明 彭花明 戴朝成 《地球环境学报》 CSCD 2024年第1期78-91,共14页
鄱阳湖作为中国最大淡水湖,其周边发育若干沙山。虽然此前研究多认为这些沙山为风力堆积的产物,但是这些沙山中上部还普遍保存有水成沉积构造的沉积层。选取江西省湖口县沙洲村沙山一处代表性的平行层理砂层(吴淞高程约40.3 m)为研究对... 鄱阳湖作为中国最大淡水湖,其周边发育若干沙山。虽然此前研究多认为这些沙山为风力堆积的产物,但是这些沙山中上部还普遍保存有水成沉积构造的沉积层。选取江西省湖口县沙洲村沙山一处代表性的平行层理砂层(吴淞高程约40.3 m)为研究对象,首先对目标砂层的石英和钾长石开展光释光信号回零分析。研究结果显示该砂层的石英光释光信号和钾长石光释光信号均呈现明显的晒退不均。这种现象与沉积构造解译一致,即目标沉积层为水成堆积过程的产物。之后,对目标砂层开展年代学研究,通过对比鄱阳湖湖岸一处现代平行层理砂层的光释光年代结果,将沙洲村沙山目标砂层的年代限定为全新世大暖期(石英单片和单颗粒光释光年龄分别为(6.9±1.6) ka和(6.4±2.2) ka)。 展开更多
关键词 鄱阳湖 沙山 平行层理 光释光 全新世大暖期
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江西星子镇沙岭沙山顶部一处红色砂层的粒度分析及释光年代研究
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作者 陈旭 龚志军 +2 位作者 罗明 彭花明 钟文 《地球环境学报》 CSCD 2024年第1期92-105,共14页
鄱阳湖作为我国最大淡水湖,其周边分布若干沙山。此前研究多认为这些沙山为风成堆积的产物。选取星子镇沙岭沙山顶部(吴淞高程约58.3 m)一处红色砂层(含泥质团块)为研究对象,开展粒度分析和释光测年,以进一步揭示其形成环境和年代。粒... 鄱阳湖作为我国最大淡水湖,其周边分布若干沙山。此前研究多认为这些沙山为风成堆积的产物。选取星子镇沙岭沙山顶部(吴淞高程约58.3 m)一处红色砂层(含泥质团块)为研究对象,开展粒度分析和释光测年,以进一步揭示其形成环境和年代。粒度结果为:(1)以中粗砂为主;(2)粒度分选性差;(3)频率分布曲线显示该红色砂层包含多峰;(4)概率累积曲线显示该红色砂层包含1个推移组分、2个跃移组分和4个悬移组分;(5)萨胡判别公式值均>-2.74。之后,对红色砂层下伏泥层、红色砂层和红色砂层上覆黄色砂层开展石英单颗粒释光测年,其年代分别为:(24.7±2.1) ka、(24.0±2.4) ka和(22.4±3.9) ka。研究表明该红色砂层虽然形成于MIS2阶段,但其不是干旱环境下的风成沉积砂层。 展开更多
关键词 鄱阳湖 沙山 粒度 光释光测年 红色砂层
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Soundscape of the West Lake Scenic Area with profound cultural background—a case study of Evening Bell Ringing in Jingci Temple,China 被引量:9
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作者 Jian GE Min GUO Miao YUE 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2013年第3期219-229,共11页
From the case study of Evening Bell Ringing at Nanping Hill,one of the West Lake Cultural Landscapes in Hangzhou,China,we investigated the soundscape of a scenic area with a profound cultural background.First,we condu... From the case study of Evening Bell Ringing at Nanping Hill,one of the West Lake Cultural Landscapes in Hangzhou,China,we investigated the soundscape of a scenic area with a profound cultural background.First,we conducted the soundscape physical index of the area in both winter and spring seasons to analyze its objective graphical expression.Second,we focused on people's reactions to the soundscape in order to obtain a subjective evaluation of each component in the soundscape and integrated environment.Then,the relationship between the objective data and the subjective evaluation was analyzed.Finally,the impacts of the natural environment,history,and cultural factors on the evaluation of the Jingci Temple soundscape were studied.It was found that natural sounds,cultural sounds,and historic sounds were widely acclaimed in people's subjective feelings,which indicated the close relationships among historical and cultural background,soundscape,and natural environment.Thus,the conclusion was made that soundscape should be consistent with the local natural environment and the historical and cultural background. 展开更多
关键词 SOUNDSCAPE Culture Evaluation West lake Evening Bell Ringing at Nanping hill
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市中跨湖桥梁的空间利用规划策略分析
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作者 龚伟江 《工程建设与设计》 2024年第7期100-102,共3页
基于跨湖桥梁空间派生性和半封闭性的特征,分析了城市桥梁空间的特征和管理使用现状。从空间规划管理的功能性、服务性以及生态发展地位3个角度提出了空间利用规划策略。同时以绍兴嵊州马桥慢行桥为例,分析市中跨湖桥梁下的空间利用策略。
关键词 城市建筑 市中跨湖桥梁 空间规划 生态湖景
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沙化程度和林龄对湿地松叶片及林下土壤C、N、P化学计量特征影响 被引量:53
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作者 胡启武 聂兰琴 +3 位作者 郑艳明 吴琴 尧波 郑林 《生态学报》 CAS CSCD 北大核心 2014年第9期2246-2255,共10页
为阐明沙化程度和林龄对湿地松(Pinus elliottii)叶片及林下土壤碳(C)、氮(N)、磷(P)化学计量特征影响,探讨C、N、P化学计量比对沙山植被恢复的指示意义,在鄱阳湖多宝沙山沿沙化梯度测定了不同林龄湿地松叶片及林下土壤C、N、P含量。结... 为阐明沙化程度和林龄对湿地松(Pinus elliottii)叶片及林下土壤碳(C)、氮(N)、磷(P)化学计量特征影响,探讨C、N、P化学计量比对沙山植被恢复的指示意义,在鄱阳湖多宝沙山沿沙化梯度测定了不同林龄湿地松叶片及林下土壤C、N、P含量。结果表明:1)在叶片C、N、P及其化学计量比中叶N与C∶N对沙化程度和林龄变化反应最为敏感。对于轻度与中度沙化区的5年生与10年生湿地松林,林龄、林龄与沙化程度的交互作用均对叶N及C∶N产生显著影响;对于中度与重度沙化区的2年生和10年生湿地松林,林龄和沙化程度均显著影响叶N与C∶N。2)叶片与土壤二者C、N、P及化学计量比对沙化程度与林龄变化的响应不完全一致。林龄、林龄与沙化程度的交互作用对轻度与中度沙化区5年生和10年生湿地松林土壤全N有显著影响;对于中度与重度沙化区2年生和10年生湿地松林,仅沙化程度对土壤全磷以及林龄对土壤有机碳影响显著。3)10年生湿地松叶片N∶P平均值为20.63,10年生以下湿地松叶片N∶P平均值为15.61,随着林龄的增加,湿地松生长由N、P共同限制逐渐转向更受P的限制。 展开更多
关键词 鄱阳湖 沙山 湿地松 化学计量学
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鄱阳湖湖滨沙山垄状地形的成因 被引量:23
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作者 韩志勇 李徐生 +4 位作者 张兆干 陈英勇 杨达源 弋双文 鹿化煜 《地理学报》 EI CSCD 北大核心 2010年第3期331-338,共8页
江西星子县沙岭沙山位于鄱阳湖湖滨,临湖一侧发育顺盛行风方向延伸的垄状地形。研究从地貌学、沉积学和年代学的角度分析了垄状地形的成因。按照目前的风场计算出的沙丘走向与合成输沙方向近于垂直,说明这些垄状地形不是纵向沙丘。垄状... 江西星子县沙岭沙山位于鄱阳湖湖滨,临湖一侧发育顺盛行风方向延伸的垄状地形。研究从地貌学、沉积学和年代学的角度分析了垄状地形的成因。按照目前的风场计算出的沙丘走向与合成输沙方向近于垂直,说明这些垄状地形不是纵向沙丘。垄状地形内部发育平行层理,缺少滑动面,则进一步表明垄状地形并非沙丘。对垄状地形之间的沟谷形态观察后发现,这些沟谷与前丘上槽形风蚀坑形态颇为相似,且沙山的环境具备发育槽形风蚀坑的基本条件,所以我们将垄状地形之间的沟谷视为槽形风蚀坑。为确定风蚀坑的形成时代,我们在沙山上风区、下风区边缘选取了6个剖面,测得的28个光释光年龄显示,构成垄状地形的沙层堆积于约20kaBP以前的末次冰期。据此我们推测在冬季风最强的阶段(18-14kaBP),沙山由以前的风沙堆积转变为风沙侵蚀,产生了槽形风蚀坑。相邻槽形风蚀坑之间的条状突起就构成了垄状地形,因此星子县沙岭沙山临湖一侧的垄状地形属于风蚀地貌。 展开更多
关键词 鄱阳湖 沙山 垄状地形 风蚀坑 光释光 地理学
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鄱阳湖沙山地区沙化土地特征及成因分析 被引量:27
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作者 丁明军 郑林 聂勇 《水土保持通报》 CSCD 北大核心 2010年第2期159-163,共5页
鄱阳湖沙山地区土地沙化属于南方荒漠化的一种典型类型,是在湖滨沙质阶地的基础上形成的,它既有别于北方的土地沙漠化,又区别于南方其它类型的荒漠化。基于野外调查的基础上对该地区土地沙化特征进行描述,同时从历史背景、当代气候特征... 鄱阳湖沙山地区土地沙化属于南方荒漠化的一种典型类型,是在湖滨沙质阶地的基础上形成的,它既有别于北方的土地沙漠化,又区别于南方其它类型的荒漠化。基于野外调查的基础上对该地区土地沙化特征进行描述,同时从历史背景、当代气候特征以及鄱阳湖水位变化等几个方面对沙化的成因进行了分析。分析结果表明:(1)目前该地区土地沙化趋于变好态势;(2)历史上的海平面变化及气候特征成为鄱阳湖沙山形成的主要因素,而沙山又为该地区当代土地沙化提供了丰富的物质来源。(3)当代气候特征下,流水及固定风向的长期侵蚀为土地沙化提供了动力因素,而鄱阳湖水位的周期性变化,为土地沙化的物质循环提供了有利的环境。总的来说,鄱阳湖沙山地区的土地沙化是在历史地质地貌变迁、当代气候条件、湖泊变化以及人为活动等因素的共同作用下形成的独具特色的亚热带土地荒漠化。 展开更多
关键词 鄱阳湖 土地沙化 沙山 成因
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南极拉斯曼丘陵湖泊水化学特征 被引量:5
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作者 李植生 王骥 +3 位作者 雷志洪 梁小民 陈旭东 梁彦龄 《极地研究》 CAS CSCD 1997年第1期71-77,共7页
本文介绍南极拉斯曼丘陵湖泊水化学特征。对13个湖泊的调查和统计分析表明,湖水以Na+和Cl-为主要优势离子,不含有CO32-离子,营养物质(N、P、SiO2)在湖水中普遍偏低,而且湖水和雪样无机氮组分均以NH4+为主... 本文介绍南极拉斯曼丘陵湖泊水化学特征。对13个湖泊的调查和统计分析表明,湖水以Na+和Cl-为主要优势离子,不含有CO32-离子,营养物质(N、P、SiO2)在湖水中普遍偏低,而且湖水和雪样无机氮组分均以NH4+为主,水化学类型比较单一,都属氯化物Na+型贫营养水体。Na+、Cl-、SO42-的高浓度,特别是Big湖、莫愁湖和Heart湖水中离子含量明显的高,指示拉斯曼丘陵地区的降水来源以海洋气团为主,并受海洋环境影响强烈。微量元素分布在0.01~2.0μg/l之间,接近于水圈这些元素的浓度值。 展开更多
关键词 拉斯曼丘陵 淡水湖泊 湖泊 水化学 湖水
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鄱阳湖滨沙岭地区网纹层的顶界年代 被引量:5
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作者 韩志勇 李徐生 +3 位作者 陈英勇 弋双文 鹿化煜 杨达源 《地理科学》 CSCD 北大核心 2012年第1期110-115,共6页
鄱阳湖滨沙岭地区的沙山由交替出现的砂层与粉砂层构成。对3个剖面的调查发现,该地区发育的网纹大体可分为3种类型,Ⅰ类网纹密集且粗大,为典型的网纹,位于剖面底部,Ⅱ类网纹较稀疏、细,位于Ⅰ类网纹之上,Ⅲ类网纹界线模糊,位于剖面上部... 鄱阳湖滨沙岭地区的沙山由交替出现的砂层与粉砂层构成。对3个剖面的调查发现,该地区发育的网纹大体可分为3种类型,Ⅰ类网纹密集且粗大,为典型的网纹,位于剖面底部,Ⅱ类网纹较稀疏、细,位于Ⅰ类网纹之上,Ⅲ类网纹界线模糊,位于剖面上部。Ⅰ类、Ⅱ类网纹属于成熟的网纹,而Ⅲ类属于不成熟的网纹。对剖面中砂层的光释光测年表明,测量等效剂量时没有出现信号饱和的问题,年剂量也没有受风化作用的影响,因而OSL年龄可以视为砂层的沉积年龄。基于砂层的沉积年龄,我们判断成熟网纹层的沉积时代早于80 ka,不成熟网纹层的沉积时代略晚于71 ka,而早于29 ka。 展开更多
关键词 网纹 沙山 光释光 鄱阳湖
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杭州西湖山区不同植被类型植物多样性比较研究 被引量:12
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作者 邓志平 卢毅军 +1 位作者 谢佳彦 江燕 《中国生态农业学报》 CAS CSCD 2008年第1期25-29,共5页
对杭州西湖山区常绿阔叶林(EBLF)、落叶阔叶林(DBLF)和针叶阔叶混交林(NBLMF)3种植被类型的群落多样性指数进行比较。结果表明:落叶阔叶林具有较高的物种多样性,针叶阔叶混交林物种多样性较低;在垂直结构物种多样性比较中,常... 对杭州西湖山区常绿阔叶林(EBLF)、落叶阔叶林(DBLF)和针叶阔叶混交林(NBLMF)3种植被类型的群落多样性指数进行比较。结果表明:落叶阔叶林具有较高的物种多样性,针叶阔叶混交林物种多样性较低;在垂直结构物种多样性比较中,常绿阔叶林和针叶阔叶混交林为灌木层〉乔木层〉草本层,而落叶阔叶林为灌木层〉草本层〉乔木层;枯立木在常绿阔叶林中主要存在于6~10m高度,而落叶阔叶林和针叶阔叶混交林中主要存在于3~4m高度。与其他各地植被类型相比,常绿阔叶林和落叶阔叶林群落物种多样性随纬度增加而减少。 展开更多
关键词 杭州 西湖山区 植被类型 植物多样性
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基于GIS的栅格化坡面径流路径模拟与LS值计算 被引量:12
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作者 吴东亮 刘鹏举 +2 位作者 唐小明 朱清科 朱金兆 《北京林业大学学报》 EI CAS CSCD 北大核心 2001年第5期10-14,共5页
该研究旨在研制建立适合我国黄土区以小流域为单元、基于GIS栅格化的坡面径流路径及土壤侵蚀强度空间分异分析模拟模型 .以ViewGIS为平台 ,将流域图经栅格化处理和建立基于栅格化处理的关系型数据库 ,利用D8方法和DEMON方法 ,分析模拟... 该研究旨在研制建立适合我国黄土区以小流域为单元、基于GIS栅格化的坡面径流路径及土壤侵蚀强度空间分异分析模拟模型 .以ViewGIS为平台 ,将流域图经栅格化处理和建立基于栅格化处理的关系型数据库 ,利用D8方法和DEMON方法 ,分析模拟径流路径 ;开发出了适于分析模拟黄土区小流域土壤侵蚀强度空间分布的模块 ,以小流域为单元对坡面径流路径进行了模拟 ,并模拟计算了通用水土流失方程的地形因子LS值在该流域坡面的分布 ,最后将计算结果存放于关系型数据库中 .该研究深入ViewGIS内核 ,在开发DEM径流分析、土壤侵蚀等功能的基础上 ,实现了对整个流域径流路径及土壤侵蚀地形地貌分异规律的计算机分析模拟与成图 。 展开更多
关键词 GIS DEM 栅格化 坡面径流模拟 LS值计算 流域 土壤侵蚀
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船舶操纵模拟器视景中的山形建模 被引量:4
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作者 兰培真 金一丞 +3 位作者 尹勇 任鸿翔 孙腾达 刘斯云 《中国图象图形学报(A辑)》 CSCD 北大核心 2001年第4期378-382,共5页
船舶操纵模拟器是一种能够部分模仿海上真实情况 ,专门为满足航海教育与培训、航海技术研究等目的而设计研制的装置 ,其核心技术之一是海上视景模拟 ,而地形地貌是海上视景中的重要组成部分 .根据船舶操纵模拟器实时视景显示的需要 ,在... 船舶操纵模拟器是一种能够部分模仿海上真实情况 ,专门为满足航海教育与培训、航海技术研究等目的而设计研制的装置 ,其核心技术之一是海上视景模拟 ,而地形地貌是海上视景中的重要组成部分 .根据船舶操纵模拟器实时视景显示的需要 ,在分析航行船舶对可视范围内重要岛屿与背景山脉的几何精度要求的基础上 ,提出了基于等高线的山形堆积建模和山形轮廓建模方法 ,并给出了山形轮廓图形的误差定义、有效适用范围 ,以及船舶操纵模拟器中地形建模的误差准则 ,该方法生成图形的数据量较小 ,其图形更新速率与几何精度能达到船舶操纵模拟器实时视景显示的要求 . 展开更多
关键词 船舶操纵模拟器 山形造型 仿真 视景生成 等高线 山形堆积建模 山形轮廓建模
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