Monitoring of percolation water to discriminate surficial inputs in a karst aquifer     

S. Covelli  F. Cucchi  R. Mosca 《Environmental Geology》1998,36(3-4):296-304

 A long-term study on the chemistry of percolating waters in a very large touristic karst cave (Grotta Gigante, northern Italy) was carried out in order to define recharge zones, flowpaths, and possible anthropogenic contamination from the neighboring area. On the basis of a multivaried analysis of the chemical parameters, a discrimination of the dripping points was attempted. Percolation waters whose recharge zone is in the northernmost sector of the cave appeared permanently affected by the anthropic settlements and agricultural activity on the ground surface. Received: 28 April 1997 · Accepted: 3 February 1998  相似文献   

“源-汇”景观格局的热岛效应研究——以武汉市为例   总被引：1，自引：0，他引：1  

高静  龚健  李靖业 《地理科学进展》2019,38(11):1770-1782

论文基于2017年Landsat 8遥感影像,通过GIS技术选取城市地表温度、源汇景观密度、源汇景观贡献度和景观效应指数,结合地理空间分析和数理统计方法,分析了武汉市局部源汇景观格局对城市地表温度的贡献及其效应。结果表明：① 武汉市城区热岛(urban heat island, UHI)季节变化明显,夏季热岛强度大、范围广,呈“大”字型分布,工业集聚区和经济开发区产生的UHI更显著;② 武汉市城区平均地表温度(land surface temperature, LST)在距市中心约8 km处达到峰值后沿城乡梯度逐渐下降,呈现“倒钩型”特征,这一现象与景观密度变化密切相关;③ LST与源(正向)、汇(负向)景观密度存在极强相关性,不透水表面是城区热岛的主要贡献因子;④ 相同密度的水体和绿地,水体更具有削弱城市热岛效应的功能;⑤ 一般当汇-源景观面积比>0.89(汇区密度>0.47)时,局部景观格局对城市热岛有缓解作用,且局部汇区越集中缓解效果越显著。  相似文献   

传统村落景观基因信息链与自动识别模型构建——以陕西省为例   总被引：2，自引：0，他引：2  

杨晓俊  方传珊  王益益 《地理研究》2019,38(6):1378-1388

传统村落作为活的文化遗产,承载了大量历史记忆,是地域文化景观基因识别与模型构建研究的重要切入点。以陕西省71个国家级传统村落为例,基于景观基因理论建立陕西省传统村落景观基因识别体系,识别出陕西省传统村落景观基因特征;运用类型学原理和N级编码理论对景观基因进行编码,构建陕西省传统村落景观基因信息链并生成基因谱系;借鉴生物学中“胞-链-形”DNA碱基序列模型,提取出环境基因、建筑基因、农耕文化基因和宗族文化基因四个公共基因作为景观基因元（胞）,以村内道路系统作为基因链,构建传统村落景观基因DNA模型与自动识别模型,以此对传统村落的区位、类型、特征和文化基因进行自动识别。为传统村落景观基因信息有效传承与存储,以及乡村建设动态发展提供理论借鉴。  相似文献   

Integration of InVEST-habitat quality model with landscape pattern indexes to assess mountain plant biodiversity change: A case study of Bailongjiang watershed in Gansu Province   总被引：1，自引：2，他引：1  

Gong  Jie  Xie  Yuchu  Cao  Erjia  Huang  Qiuyan  Li  Hongying 《地理学报(英文版)》2019,29(7):1193-1210

Journal of Geographical Sciences - Mountains in western China, hosted rich biodiversity and millions of people and inhabitant with vital ecosystem services, had experienced the most serious...  相似文献   

贝塞尔曲线在虚拟森林景观单树几何模型构建中的应用   总被引：10，自引：0，他引：10  

石松於其之  陈崇成朱泉锋 《地球信息科学学报》2004,6(3):90-93

虚拟景观模型的生成,需要对实际景观进行抽象和简化。树几何模型和数字高程模型(DEM)是构成虚拟森林景观的两大要素。而树几何模型的构建又是林业GIS三维可视化的基础。在树几何建模中,树干及树枝形状的可视化表达具有突出意义。由于实际树种的复杂性,在计算机中建树模型,通常采用基于过程建模的方式,而这将面临用户如何对模型进行交互式控制的问题：参数太少,不足以描述树形态特征,而参数太多,则模型难以生成和理解。为了解决这个问题,我们引进贝塞尔(Bezier)曲线这种基于控制点的自由曲线来描述树木中的树干以及树枝形状,利用对曲线控制点的变动来控制曲线的形状,进而生成形态各异的树形状,对此,我们基于ActiveX技术生成Bezier曲线控件。结果表明,该方法能够表示多种形状的树干与树枝,具有操作简捷、计算速度快,可视化效果良好的优点。  相似文献   

基于景观格局指数的基本农田保护区集中连片性研究——以济南市历城区为例   总被引：1，自引：0，他引：1       下载免费PDF全文

张保华  王雷  白振华  潘庆龙  汤庆新  肖燕 《山东国土资源》2014,30(2):80-82

耕地与基本农田保护是我国土地管理、土地利用规划的重要内容。新一轮土地利用总体规划修编及数据库建设中要求基本农田调整布局更加集中连片。该文应用景观格局指数,研究了济南市历城区基本农田保护区规划调整中集中连片性的变化。结果表明,除保护区图斑面积标准差外,图斑平均面积、图斑面积变异系数、图斑边界密度、最大斑块指数、平均欧式邻近距离5项指标均表明,规划调整后基本农田保护区布局上更加集中连片。为基本农田保护区布局的集中连片性判断提供了简便易行的方法。  相似文献   

山东省东平县大洪顶山地区岩溶洞穴景观资源评价          下载免费PDF全文

唐苏芹  曾理 《山东国土资源》2014,30(3):78-81,85

东平县大洪顶山岩溶地貌类型属岩溶山地地貌单元,山坡顶部及陡峭坡段岩石裸露,岩溶裂隙发育,岩体切割破碎,边坡陡立。区内岩溶洞穴发育,岩溶景观资源众多。目前已发现的溶洞有6处,大洪顶山南坡3处,北坡3处,溶洞口出露位置呈NWW向展布,北部九仙洞已探测长度1 862 m,南部神仙洞已探测长度2 052.50 m,溶洞内岩溶景观发育不均匀,发育有石笋、石钟乳、石幔、石帽、边石等。区内岩溶洞穴发育规模宏大,景观资源丰富,属鲁西地区发育规模最大的溶洞,在北方地区具代表性、典型性、稀有性,属我国北方地区不可多得的地质自然遗产,具有良好的开发前景及旅游价值。  相似文献   

Structural and fluid evolution of Saraburi Group sedimentary carbonates,central Thailand: A tectonically driven fluid system     

《Marine and Petroleum Geology》2014

A stable isotopic study, focused on calcite cements, vein-fill calcite and various bioclasts was conducted on variably deformed and thrusted Lower and Middle Permian carbonates of the Saraburi Group. Samples were collected in quarry faces across 3 areas in the Saraburi–Lopburi region of central Thailand. Stable isotope crossplots (carbon and oxygen), using texture-aware isotope samples, defined variable, but related, fluid-cement histories, which are tied to regional burial and then orogenic overprints driven by the Indosinian (Triassic) orogeny. This was followed by telogenetic overprints, driven by late Cenozoic uplift. The studied carbonates were deposited along the western margin of the Indochina Block, where they were deposited as isolated calcareous algal, sponge and fusilinid-rimmed platforms on highs bound by extensional faults. The platform areas passed laterally and vertically into more siliciclastic dominated sequences, deposited in somewhat deeper waters within probable fault-bound lows. Regional post-depositional mesogenetic fluid-rock re-equilibration of the isotope values in ongoing calcite precipitates occurred until the matrix permeability was occluded via compaction and pressure solution. This regional burial regime was followed by collision of the Indochina and Sibumasu blocks during the Indosinian (Triassic) blocks, which drove a set of structurally focused (thrust-plane related) increasingly warmer set of fluids through the studied sequences. The final diagenetic overprint seen in the isotopic values of the latest calcite cements occurs in a telogenetic (uplift) setting driven by Cenozoic tectonics and isostatic uplift. Integration of isotope data with its structural setting establishes a clear separation in fluid events related to two time-separate tectonic episodes; its fluid chemistry defines the Permo-Triassic closure of the Paleotethys and its subsequent reactivation during the Tertiary collision of India and Asia. The C–O covariant plot fields in the Permian carbonates of central Thailand are so distinct that it is possible to use their signatures to separate burial from meteoric cements in drill cuttings and hence recognise equivalent subsurface unconformities and likely zone of porosity development in possible “buried hill plays in Thailand.  相似文献   

Effects of corridor networks on plant species composition and diversity in an intensive agriculture landscape     

Qian Tang  Guofu Liang  Xunling Lu  Shengyan Ding 《中国地理科学(英文版)》2014,24(1):93-103

The development of modern agriculture has resulted in much homogenization of the landscape consisting of large patches of farmland,so small remnant non-crop habitats especially linear corridors play an important role in the conservation of species and the maintenance of ecosystem functions.However,little attention has been paid to the effects of corridors structural characteristics on the plant species restricted to such habitats.In this study,we selected three types of corridors including ditch,hedgerow and road,and ana-lyzed their structural characteristics.The plant species presented in these corridors were investigated,and the species diversity,abun-dance and frequency were estimated.Moreover,spatial arrangements of corridors were classified into different types to discuss whether there were significant effects of corridor network on plant distribution.The results show that three types of corridors have different ef-fects on plant species composition and diversity.The one-one combined corridor networks and total network associated by three corri-dors have more complex structural features than each single type of corridor.However,there is no strong correlation between the corri-dor networks with their plant species.We suggest that carrying out a pointed vegetation survey at corridor intersections to further test the relationships between structural features of corridor and plants is necessary.  相似文献   

A landscape pattern analysis method based on boundaries and nodes: A case study in upper Minjiang River, China     

Qingchun Wen  Xiuzhen Li  Hongshi He  Yuanman Hu  Xin Chen  Yu Chang  Wei Wang  Rencang Bu 《中国地理科学(英文版)》2014,24(1):50-59

Traditionally,patch-based analysis at the landscape scale fragmentation has been used in the study of landscape ecology while the study of boundary and node has not been considered as much detail until recently.This study investigated the possibility of applying boundary-and node-based methods in landscape pattern analysis to the upper reaches of the Minjiang River in the southwestern China.Boundary-based and node-based landscape indices were selected to be used in analyzing changes in landscape patterns,and the results were compared with analysis using traditional pattern indices.We compared the responses of patch-area-based,boundary-length-based and node-number-based indices,and concluded that boundary-based and node-based indices are more sensitive to disturbance than patch-based indices with various patterns,and node-based indices are even more sensitive than boundary-based ones.Thus,the results suggest that boundary-based and node-based pattern analysis methods provide helpful supplementary information to traditional patch-based pattern analysis methods.The results about pattern dynamics of landscapes in the upper reaches of the Minjiang River based on boundaries and nodes showed that with human disturbance,the dominance of forest landscape was weakened by other landscape types; thus the landscape pattern of the study area became more homogeneous and the boundary network became more complex.These changes further augmented disturbance interfaces in the landscape and increased the possibilities of further landscape fragmentation.  相似文献