6,214 results
Search Results
2. Estimation of Tobacco Yield Based on the Radarsat-2 in Karst Mountainous Area
- Author
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Sun, Xiaotao, Zhou, Zhongfa, Fu, Yong, Liao, Juan, Wang, Ping, Barbosa, Simone Diniz Junqueira, Editorial Board Member, Filipe, Joaquim, Editorial Board Member, Ghosh, Ashish, Editorial Board Member, Kotenko, Igor, Editorial Board Member, Yuan, Junsong, Editorial Board Member, Zhou, Lizhu, Editorial Board Member, Bian, Fuling, editor, and Xie, Yichun, editor
- Published
- 2016
- Full Text
- View/download PDF
3. Discussion of a recent paper: M. H. Ghobadi; M. Torabi-Kaveh; M. Miri; N. Mahdiabadi; An introduction to the karst geomorphology of the Bisetun–Tāq-e Bostan historical region (northeast Kermanshah, Iran) with special emphasis on karst development as a serious threat for the UNESCO World Heritage Site, Bulletin of Engineering Geology and the Environment, DOI 10.1007/s10064-014-0662-0
- Author
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Kemp, Jonathan
- Published
- 2016
- Full Text
- View/download PDF
4. Abstracts of Additional Conference Papers
- Author
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William B. White
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geography ,geography.geographical_feature_category ,Groundwater contamination ,Environmental science ,Aquifer ,Contamination ,Karst ,Water resource management - Abstract
This chapter reproduces short abstracts of 14 papers presented at the conference for which complete papers were not submitted. These were extracted from the conference program published by the Karst Waters Institute. The abstracts summarize research on the assessment of karst groundwater contamination, contamination and public health, and hydrogeologic studies of karst aquifers and are arranged under these headings.
- Published
- 2017
5. Discussion of a recent paper: M. H. Ghobadi; M. Torabi-Kaveh; M. Miri; N. Mahdiabadi; An introduction to the karst geomorphology of the Bisetun–Tāq-e Bostan historical region (northeast Kermanshah, Iran) with special emphasis on karst development as a serious threat for the UNESCO World Heritage Site, Bulletin of Engineering Geology and the Environment, DOI 10.1007/s10064-014-0662-0
- Author
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Jonathan Kemp
- Subjects
geography ,geography.geographical_feature_category ,Engineering geology ,0211 other engineering and technologies ,Geology ,02 engineering and technology ,Unesco world heritage ,010502 geochemistry & geophysics ,Geotechnical Engineering and Engineering Geology ,Karst ,01 natural sciences ,Nature Conservation ,Geomorphology ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences - Abstract
The article under discussion, whilst providing generalized accounts of the effects of waterflows in karstic formations, fails, in the opinion of this respondent, to substantiate the claims that an immediate threat is posed to the continued preservation of the monuments at Tāq-e Bostān, the focus of this response.
- Published
- 2015
6. Response to the authors’ reply to my discussion of their paper 'An introduction to the karst geomorphology of the Bisetun-Taq-e Bostan historical region (northeast Kermanshah, Iran) with special emphasis on karst development as a serious threat for the UNESCO World Heritage Site. Bull Eng Geol Environ doi:10.1007/s10064-014-0662-0'
- Author
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Jonathan Kemp
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geography.geographical_feature_category ,0211 other engineering and technologies ,Geology ,02 engineering and technology ,Unesco world heritage ,010502 geochemistry & geophysics ,Geotechnical Engineering and Engineering Geology ,Karst ,01 natural sciences ,Archaeology ,Geography ,Nature Conservation ,Cartography ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences - Published
- 2016
7. Effect of abnormal fibres on the mechanical properties of paper made from Norway spruce, Picea abies (L.) Karst
- Author
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Geoffrey Daniel, Ann Marklund, and Nasko Terziev
- Subjects
Biomaterials ,geography ,geography.geographical_feature_category ,Materials science ,biology ,Botany ,Picea abies ,biology.organism_classification ,Karst - Abstract
The aim of the present study was to determine the effect of a variety of abnormal fibres on the mechanical properties of paper made from Norway spruce, Picea abies (L.) Karst. Fibres representing abnormality were obtained from trees treated by irrigation and fertilisation. Moreover, fibres from compression wood and its accompanying opposite wood were isolated. The effect of dislocations on paper quality was studied on four mixtures (20, 40, 60 and 80% fibres with induced dislocations) of untreated/compressed fibres. Two more groups consisting of control untreated samples and samples with 100%-induced dislocations were also included in the test. The mechanical properties of the paper were tested and the results were compared to those of control samples. Abnormal fibres reduced the desired mechanical properties of the final paper concerning tensile strength, modulus of elasticity and tear-tensile index. Irrespective of the type of treatment, all morphological changes introduced in fibre cell walls appear to directly affect changes in the mechanical properties of the paper. Control samples had a tear index of 25 compared to 10 mN m2 g-1 of samples containing 100% dislocations. It is obvious that 20% of dislocations, an amount that is expected to be induced in pulp under mechanical processing and transport, will contribute to a decrease in tear index with an average of 3 mN m2 g-1, i.e., 10% of the total value.
- Published
- 2008
8. DENUDATION MORPHOLITHOGENESIS OF THE PRIOL'KHONIE (PAPER 2. LOW HILL LANDSCAPE)
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geography ,Water erosion ,geography.geographical_feature_category ,Feature (archaeology) ,Denudation ,Crust ,Weathering ,Karst ,Geomorphology ,Substrate (marine biology) ,Geology ,Earth-Surface Processes - Abstract
Mechanisms of the three types of low hill landscape (LH) are described. LH of watersheds is forming by exhumation processes, which wash out the crust of weathering on the planation surfaces and denude the inequalities of paleo relief. Karst, deflation, sheet wash and pediments formation are important parts of this process. Formation of slope LH is well described in literature. Streamside LH rises due to water erosion under the conditions of little basis changes. Prismatic shape of the hills is its characteristic feature. Selective denudation of heterogeneous substrate complicates all three relief types.
- Published
- 2015
9. Response to the authors' reply to my discussion of their paper 'An introduction to the karst geomorphology of the Bisetun-Taq-e Bostan historical region (northeast Kermanshah, Iran) with special emphasis on karst development as a serious threat for the UNESCO World Heritage Site. Bull Eng Geol Environ doi:10.1007/s10064-014-0662-0'
- Author
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Kemp, Jonathan
- Subjects
- *
KARST ,BISUTUN Site (Iran) - Abstract
A letter to the editor is presented in response to the article "An introduction to the karst geomorphology of the Bisetun-Taq-e Bostan historical region (northeast Kermanshah, Iran) with special emphasis on karst development as a serious threat for the UNESCO World Heritage Site," by M. H. Ghobadi and colleagues in the 2014 issue.
- Published
- 2016
- Full Text
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10. Defining and Redefining the National Community - Kenneth L. Karst: Belonging to America: Equal Citizenship and the Constitution. (New Haven: Yale University Press, 1989. Pp. xii, 329. $35.00. $15.95, paper.)
- Author
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Vernon Van Dyke
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geography ,geography.geographical_feature_category ,Sociology and Political Science ,Constitution ,media_common.quotation_subject ,Political Science and International Relations ,Sociology ,Theology ,Religious studies ,Karst ,Citizenship ,Haven ,media_common - Published
- 1992
11. Karst topography; computer animations and paper model
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J. C. Tinsley, Tau Rho Alpha, and John P. Galloway
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Geography ,geography.geographical_feature_category ,Computer graphics (images) ,Karst - Published
- 1997
12. 3D seismic intelligent prediction of fault-controlled fractured-vuggy reservoirs in carbonate reservoirs based on a deep learning method.
- Author
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Li, Zongjie, Li, Haiying, Liu, Jun, Deng, Guangxiao, Gu, Hanming, and Yan, Zhe
- Subjects
CARBONATE reservoirs ,DEEP learning ,GAS reservoirs ,KARST ,PETROLEUM reservoirs ,GEOLOGICAL modeling ,FORECASTING - Abstract
Accurately predicting the external morphology and internal structure of fractured-vuggy reservoirs is of significant importance for the exploration and development of carbonate oil and gas reservoirs. Conventional seismic prediction methods suffer from serious non-uniqueness and low efficiency, while recent advances in deep learning exhibit strong feature learning capabilities and high generalization. Therefore, this paper proposes an intelligent prediction technique for fault-controlled fracture-vuggy reservoirs based on deep learning methods. The approach involves constructing 3D seismic geological models that conform to the geological characteristics of the study area, simulating seismic wavefield propagation, and combining the interpretation results of fractured-vuggy reservoirs. Training sample datasets are separately established for strike-slip faults, karst caves, and fault-controlled fractured-vuggy reservoir outlines, which are then input into the U-Net model in batches for training. This leads to the creation of a deep learning network model for fault-controlled fractured-vuggy reservoirs. The trained network model is applied to the intelligent identification of fault, karst cave, and fault-controlled fracture-vuggy reservoir outlines using actual seismic data from the Shunbei area. A comparison with traditional methods is conducted, and the experimental results demonstrate that the proposed deep learning approach shows excellent performance in the identification and prediction of fault-controlled fractured-vuggy reservoirs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
13. Reasonable Treatment Range of Karst Cave Encountered by Super-Large Diameter Shield Tunnel in Strongly Karst-Developed Area.
- Author
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Wang, Jiang, Yang, Jinwen, and Yan, Xianglin
- Subjects
KARST ,SPELEOTHEMS ,DIAMETER ,CAVES ,STALACTITES & stalagmites - Abstract
When a super-large diameter shield tunnel passes through a strongly karst-developed area, in order to ensure the stability of the tunnel and economy of karst reinforcement, the reasonable treatment range for a huge number of karst caves needs to be researched. Based on a karst treatment project of a shield tunnel with a diameter of 14.5 m, this paper studies the influence of intrusive fully filled karst caves on the stability of the lining and excavation face by using theoretical calculation. In addition, the safe distance between the tunnel and karst caves outside the tunnel is proposed through numerical simulation, and the corresponding treatment range is obtained. The results show that the bearing capacity of the lining has a certain reserve when the intrusive cave is smaller than a certain size, and the caves filled with plastic or hard plastic clay have sufficient antifracturing ability. Therefore, some small fully filled caves inside the tunnel profile can be left unreinforced. On the other side, the critical safe distance is only 1–2 m for the caves with a size of 3 m, so the outside caves with a size less than 3 m can be left unreinforced in the treatment range farther away from the tunnel. The proposed treatment range is close to similar projects that have been built, indicating that analysis results are reasonable. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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14. Book reviews : Ford, D.C. and Williams, P.W. 1989: Karst geomorphology and hydrology. London: Unwin Hyman. xv + 601 pp. £24.95 paper
- Author
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Stephen Trudgill
- Subjects
geography ,Hydrology (agriculture) ,History ,geography.geographical_feature_category ,Geography, Planning and Development ,Earth and Planetary Sciences (miscellaneous) ,General Earth and Planetary Sciences ,Environmental ethics ,Karst ,Archaeology - Published
- 1990
15. Special Paper: Forest Vegetation of the Kentucky Karst Plain (Kentucky and Tennessee): Review and Synthesis
- Author
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Carol C. Baskin, Jerry M. Baskin, E. W. Chester, and Edward W. Chester
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Geography ,geography.geographical_feature_category ,Ecology ,Forest vegetation ,Forestry ,Plant Science ,Karst ,Ecology, Evolution, Behavior and Systematics - Published
- 1997
16. Biodiversity in Karst Landscapes: Introduction to the Special Issue.
- Author
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Mičetić Stanković, Vlatka
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KARST ,LIFE zones ,ECOLOGICAL zones ,LANDSCAPES ,HABITATS - Abstract
10.3390/d14050393 3 Jakob A., Breg Valjavec M., Carni A. Turnover of Plant Species on an Ecological Gradient in Karst Dolines Is Reflected in Plant Traits: Chorotypes, Life Forms, Plant Architecture and Strategies. The third paper [[3]] addresses plant communities and their architecture in relation to the environment in a typical karst landform-enclosed terrain depression known as a doline, with a strong ecological gradient. Karst landscapes are a set of various features built of rocks that are soluble in water. [Extracted from the article]
- Published
- 2023
- Full Text
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17. Analysis of the Influence of Complex Terrain around DC Transmission Grounding Electrodes on Step Voltage.
- Author
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Xiong, Qi, Liu, Xiangyi, Li, Yanxin, Xi, Lingran, and Qiu, Shuang
- Subjects
KARST ,ELECTRODES ,RENEWABLE energy sources ,FINITE element method ,VOLTAGE - Abstract
The distribution of renewable energy sources is geographically limited. In the process of long-distance transmission, the direct current flowing from a ground electrode into the ground will cause a higher step voltage, which will bring serious security risks to the surrounding industry and life. Accurate calculation of the complex soil electrical model around the grounding electrode is crucial for site selection. Existing simulation software like CDEGS results in significant errors, particularly in complex karst topography. Therefore, constructing a finite element model that accurately reflects the characteristics of geotechnical soil near the DC grounding electrode is an essential but unresolved problem. This paper establishes a soil electrical model for karst topography and explores the impact of cave-type caverns and underground rivers on the step voltage distribution of DC grounding electrodes. These research findings can guide the site selection of DC transmission projects in karst topography. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
18. The Method of Seismic Diffraction Wave Extraction Based on PCA Method and its Application.
- Author
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Wei, Huadong, Huang, Wei, Ji, Tongzhou, Wang, Shengli, Liu, Rui, Xu, Guihong, Shu, Mengcheng, Cai, Yun, and Deng, Shenshen
- Subjects
WAVE diffraction ,SEISMIC waves ,SEPARATION (Technology) ,CAVES ,KARST ,SEISMIC migration - Abstract
This paper addresses the challenge of accurately describing the boundary of deep cavern-type reservoirs. A method is developed to extract diffraction information from the cavern and its boundaries from full wavefield seismic data using PCA wavefield separation technology. The paper describes a method for extracting diffraction information based on post-stack seismic data, and demonstrates the validity of this method in identifying cavern's boundaries via forward modeling. Subsequently, the method is applied to actual seismic data to extract diffraction information from deep caverns. By separating wavefield information at different scales, the extracted diffraction information can effectively identify the characteristics of cavernous reservoirs and their boundaries. It is verified by examples that the diffraction wave information separation method can provide a more accurate description of the distribution of deep cavern-type reservoirs, which can provide a basis for predicting this type of reservoir. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
19. Evolution and Transformation Analysis of Land-use in Mountainous "Granary"—Evidence from Typical Basin in Karst Mountainous Areas of Southwest China.
- Author
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Chen, Mei, Li, Yangbing, Zhang, Yiyi, Yu, Limin, and Yang, Linyu
- Subjects
KARST ,GRANARIES ,REGIONAL development ,LAND resource ,RURAL development - Abstract
Intermountain basins are the granaries of the karst mountains of southwest China. Revealing the process and trend of land-use transformation in typical mountainous "granaries" is of great significance to optimizing land-use, food security, and rural revitalization in the karst mountains of southwest China. Lianjiang basin in Huishui County is the largest in Guizhou Province of southwest China, and a typical mountainous "granary" is used as a case study area. Based on seven periods of high-definition remote sensing images from 1966 to 2020 and on-the-spot investigation, we adopt the analysis methods of landscape pattern, moving window, and buffer zone and conduct an in-depth study on the spatial evolution of land-use and the land-use transformation law of the typical "granaries" of karst mountainous areas in southwest China from the perspectives of changes in the quantity of land-use, changes in the types of land-use, and changes in the landscape pattern. The results showed that the transformation of land-use in the basin was mainly manifested in the transformation of the function of cultivated land and the diversification of the function of cultivated land. The landscape pattern of the basin was gradually transformed from traditional rural landscape to modern agricultural landscape. The gradient effect of land-use evolution and transformation in the study basin was obvious. Traffic, location, and land resources significantly affect land-use transformation in the basin. Based on the above analysis, this paper proposes that the "granary" basins in karst mountainous areas should optimize the land-use of the basin by the trade-off between regional socio-economic development, ecological protection, and food security. The results of this paper provide a reference for land-use optimization and rural development in the granary-type basins and other similar areas in the karst mountains of southwest China. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
20. The Global Situation of Karst Desertification Research Based on Forest Ecology.
- Author
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Zhang, Yu, Zhang, Zhaohui, Zhang, Mingsheng, and Yuan, Zhouwei
- Subjects
FOREST ecology ,KARST ,DESERTIFICATION - Abstract
Karst desertification (KD) is a major ecological and environmental problem threatening human survival and development in karst areas. In order to explore the research situation and development trend of KD based on forest ecology, this paper provides a systematic literature review based on the CNKI and WoS databases, which involves search, appraisal, synthesis, and analysis. We performed a statistical and visual analysis of 2955 studies acquired between 1 January 1995 and 30 June 2023, including the time distribution of the studies, hot research trends, pivotal research clusters, literature co-citations, main publishing trends, and keyword bursts. The results show the following. (1) The literature shows a fluctuating growth trend, and the research trends are divided into accumulation, development, and expansion stages. (2) The pivotal research clusters comprised three major aspects: study area and method, driving and genetic mechanisms, and control technology and models. (3) KD research forms a China-centered research network, dominated by institutions and scholars in southwestern China. (4) Future research needs to solve a series of related scientific issues and technological needs for forest ecosystem function optimization, ecological product supply capacity enhancement, ecological product value realization, ecological industry formation, and rural revitalization in KD control. The purpose of this paper is to reveal research trends relating to KD and highlight the future direction of KD research and control. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
21. Characterising thermal water circulation in fractured bedrock using a multidisciplinary approach: a case study of St. Gorman’s Well, Ireland
- Author
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Mark R. Muller, John Paul Moore, Volker Rath, John Murray, Alan G. Jones, Joan Campanyà, Sarah Blake, Tiernan Henry, and John J. Walsh
- Subjects
Paper ,010504 meteorology & atmospheric sciences ,Lithology ,Geothermal exploration ,Geochemistry ,Karst ,Fault (geology) ,010502 geochemistry & geophysics ,01 natural sciences ,Hydrothermal circulation ,Carboniferous ,Spring (hydrology) ,Fractured rocks ,Earth and Planetary Sciences (miscellaneous) ,0105 earth and related environmental sciences ,Water Science and Technology ,geography ,geography.geographical_feature_category ,Geophysical methods ,Bedrock ,Thermal springs ,13. Climate action ,Ireland ,Geology - Abstract
A hydrogeological conceptual model of the source, circulation pathways and temporal variation of a low-enthalpy thermal spring in a fractured limestone setting is derived from a multidisciplinary approach. St. Gorman's Well is a thermal spring in east-central Ireland with a complex and variable temperature profile (maximum of 21.8 °C). Geophysical data from a three-dimensional(3D)audio-magnetotelluric(AMT) survey are combined with time-lapse hydrogeological data and information from a previously published hydrochemical analysis to investigate the operation of this intriguing hydrothermal system. Hydrochemical analysis and time-lapse measurements suggest that the thermal waters flow within the fractured limestones of the Carboniferous Dublin Basin at all times but display variability in discharge and temperature. The 3D electrical resistivity model of the subsurface revealed two prominent structures: (1) a NW-aligned faulted contact between two limestone lithologies; and (2) a dissolutionally enhanced, N-aligned, fault of probable Cenozoic age. The intersection of these two structures, which has allowed for karstification of the limestone bedrock, has created conduits facilitating the operation of relatively deep hydrothermal circulation (likely estimated depths between 240 and 1,000 m) within the limestone succession of the Dublin Basin. The results of this study support a hypothesis that the maximum temperature and simultaneous increased discharge observed at St. Gorman's Well each winter is the result of rapid infiltration, heating and recirculation of meteoric waters within a structurally controlled hydrothermal circulation system.The online version contains supplementary material available at 10.1007/s10040-021-02393-1.Un modèle conceptuel hydrogéologique de la source, des voies de circulation et de la variation temporelle d’une source thermale à faible enthalpie dans un contexte de calcaire fracturé est dérivé d’une approche multidisciplinaire. St. Gorman’s Well est une source thermale du centre-est de l’Irlande avec un profil de température complexe et variable (maximum de 21.8 °C). Les données géophysiques d’un levé audio-magnétotellurique (AMT) en trois dimensions (3D) sont combinées avec des données hydrogéologiques à intervalles de temps et des informations provenant d’une analyse hydrochimique publiée précédemment pour étudier le fonctionnement de cet intrigant système hydrothermal. L’analyse hydrochimique et les mesures à différentes périodes suggèrent que les eaux thermales s’écoulent à tout moment dans les calcaires fracturés du bassin carbonifère de Dublin, mais présentent une variabilité de débit et de température. Le modèle de résistivité électrique 3D du sous-sol a révélé deux structures importantes: (1) un contact faillé orienté NW entre deux lithologies calcaires; et (2) une faille alignée au Nord, améliorée par dissolution, d’âge cénozoïque probable. L’intersection de ces deux structures, qui a permis la karstification du socle calcaire, a créé des conduits facilitant le fonctionnement d’une circulation hydrothermale relativement profonde (profondeurs estimées vraisemblablement entre 240 et 1,000 m) au sein de la succession calcaire du bassin de Dublin. Les résultats de cette étude appuient l’hypothèse selon laquelle la température maximale et l’augmentation simultanée du débit observés à St. Gorman’s Well chaque hiver sont le résultat d’une infiltration, d’un réchauffement et d’une recirculation rapides des eaux météoriques dans un système de circulation hydrothermale structurellement contrôlé.Se deriva un modelo conceptual hidrogeológico de la fuente, las vías de circulación y la variación temporal de un manantial termal de baja entalpía en un entorno de caliza fracturada a partir de un enfoque multidisciplinar. Gorman’s Well es un manantial termal en el centro-este de Irlanda con un perfil de temperatura complejo y variable (máximo de 21.8 °C). Los datos geofísicos de un estudio audio-magnetotelúrico (AMT) tridimensional (3D) se combinan con los datos hidrogeológicos de un lapso de tiempo y la información de un análisis hidroquímico previamente publicado para investigar el funcionamiento de este intrigante sistema hidrotermal. El análisis hidroquímico y las mediciones a intervalos de tiempo sugieren que las aguas termales fluyen dentro de las calizas fracturadas de la cuenca carbonífera de Dublín en todo momento, pero muestran variabilidad en la descarga y la temperatura. El modelo de resistividad eléctrica tridimensional del subsuelo reveló dos estructuras prominentes: (1) un contacto de falla alineado al NW entre dos litologías calcáreas; y (2) una falla de disolución incrementada, alineada al N, de probable edad cenozoica. La intersección de estas dos estructuras, que ha permitido la karstificación del lecho rocoso calcáreo, ha creado conductos que facilitan el funcionamiento de una circulación hidrotermal relativamente profunda (probablemente a profundidades estimadas entre 240 y 1,000 m) dentro de la sucesión calcárea de la cuenca de Dublín. Los resultados de este estudio apoyan la hipótesis de que la temperatura máxima y el aumento simultáneo de la descarga observados en St. Gorman’s Well cada invierno son el resultado de una rápida infiltración, calentamiento y recirculación de aguas meteóricas dentro de un sistema de circulación hidrotermal estructuralmente controlado.通过多学科方法, 建立了裂缝型石灰岩环境中低焓温泉的来源、循环路径和时间变化的水文地质概念模型。圣戈尔曼井是爱尔兰中东部的温泉, 温度分布复杂多变 (最高21.8 °C)。将三维 (3D) 音频-大地电磁 (AMT) 调查的地球物理数据与延时水文地质数据和先前发布的水化学分析信息相结合, 调查了有趣的热液系统运行情况。水化学分析和延时测量表明, 热水一直在石炭系都柏林盆地的裂缝型石灰岩内流动, 但流量和温度有变异性。地下的 3D 电阻率模型揭示了两个突出的结构:(1) 两个石灰岩岩性之间的 NW 向断层接触; 和 (2) 可能新生代的溶蚀增强的和N向的断层。两个结构的交叉点使石灰岩基岩发生岩溶作用, 形成了通道, 促进了都柏林盆地石灰岩序列内相对较深的热液循环 (估计深度可能在 240 至 1,000 m 之间)作用。通过这项研究发现每年冬天在圣戈尔曼井观察到的最高温度和同时增加的排泄量是结构控制的热液循环系统中大气水快速入渗、加热和再循环的结果。.Um modelo hidrogeológico conceitual da fonte, vias de circulação e variação temporal de uma fonte termal de baixa entalpia em um ambiente de calcário fraturado é derivado de uma abordagem multidisciplinar. O poço de St. Gorman é uma fonte termal no centro-leste da Irlanda com um perfil de temperatura complexo e variável (máximo de 21.8°C). Os dados geofísicos de uma pesquisa áudio-magnetotelúrica (AMT) tridimensional (3D) são combinados com dados hidrogeológicos em intervalos de tempo e informações de uma análise hidroquimica publicada anteriormente, para investigar a operação deste intrigante sistema hidrotérmico. A análise hidroquimica e as medições em intervalos de tempo sugerem que as águas termais fluem de dentro dos calcários fraturados da Bacia Carbonifera de Dublin o tempo todo, mas exibem variabilidade na descarga e na temperatura. O modelo de resistividade elétrica 3D da subsuperfície revelou duas estruturas proeminentes: (1) um contato defeituoso alinhado a NO entre duas litologias de calcário; e (2) uma falha dissolucionalmente aumentada, alinhada a N, de provável idade Cenozóica. A intersecção dessas duas estruturas, que permitiu a carstificação da rocha calcária, criou condutos que facilitam a operação de circulação hidrotérmica relativamente profunda (profundidade estimada entre 240 e 1,000 m) dentro da sucessão de calcário da Bacia Dublin. Os resultados desse estudo suportam a hipótese de que a temperatura máxima e o aumento simultâneo da descarga observada no poço de St. Gorman a cada inverno é o resultado da rápida infiltração, aquecimento e recirculação de águas meteóricas dentro de um sistema de circulação hidrotérmica estruturalmente controlado.
- Published
- 2021
22. An evaluation of semidistributed-pipe-network and distributed-finite-difference models to simulate karst systems
- Author
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Laurence Gill, Patrick Morrissey, Philip Schuler, Paul Johnston, and Lea Duran
- Subjects
Paper ,Submarine groundwater discharge ,010504 meteorology & atmospheric sciences ,0207 environmental engineering ,Karst ,Context (language use) ,Aquifer ,02 engineering and technology ,01 natural sciences ,Civil engineering ,Earth and Planetary Sciences (miscellaneous) ,020701 environmental engineering ,0105 earth and related environmental sciences ,Water Science and Technology ,geography ,Hydrogeology ,geography.geographical_feature_category ,Distributed element model ,MODFLOW ,Groundwater recharge ,6. Clean water ,Groundwater/surface-water relations ,Numerical modelling ,Ireland ,Geology - Abstract
Several different approaches have been developed to model the specific characteristics of karst aquifers, taking account of their inherent complex spatial and temporal heterogeneities. This paper sets out the development of a semidistributed modelling approach for applications in an Irish karst context using urban drainage software. The models have proven to be very useful for different studies, with examples given for the ecohydrology of ephemeral karst lakes, extreme groundwater-flood alleviation, karst network investigation, submarine groundwater discharge, and quantification of different recharge and flow components. The limitations of the approach are also highlighted, in particular not being able to simulate diffuse infiltration and flow paths explicitly across the groundwater catchment. Hence, a more distributed, finite-difference modelling approach using MODFLOW Unstructured Grid (USG) with the newly developed Connected Linear Network (CLN) process is then compared against the semidistributed approach on the same karst catchment. Whilst it has proven difficult to achieve the same levels of model performance in simulating the spring flows in the distributed model compared to the semidistributed model, the ability to interrogate the flow paths at any point on the three-dimensional aquifer is demonstrated, which can give new insights into flows (and potential contaminant transport) through such complex systems. The influence of the proximity of highly transmissive conduits on the flow dynamics through the much-lower transmissive matrix cells in which the network is embedded has been particularly investigated.Plusieurs approches différentes ont été développées pour modéliser les caractéristiques spécifiques des aquifères karstiques, prenant en compte leurs hétérogénéités spatiales et temporelles associées à leur complexité intrinsèque. Cet article présente le développement d’une approche de modélisation semi-distribuée appliquée à un contexte karstique irlandais en utilisant un logiciel de drainage urbain. Ces modèles se sont avérés très utiles pour différentes études, avec des exemples appliqués à l’écohydrologie de lacs karstiques éphémères, l’atténuation de crues extrêmes liées aux eaux souterraines, à l’étude du réseau karstique, à la décharge des sources sous-marines et à la quantification des différentes composantes aussi bien de la recharge que du débit. Les limites de cette approche sont aussi mises en évidence, avec en particulier l’incapacité de simuler l’infiltration diffuse et les voies d’écoulement de manière explicite au sein du bassin d’alimentation d’eaux souterraines. Par conséquent, une approche de modélisation plus distribuée aux différences finies utilisant le logiciel MODFLOW avec une grille non structurée (USG) intégrant le processus récemment développé de réseau linéaire connecté (CLN) est ensuite comparée à l’approche semi-distribuée appliquée au même bassin karstique. Alors qu’il s’est avéré difficile d’atteindre les mêmes niveaux de performance du modèle concernant la simulation du débit à la source à l’aide du modèle distribué en comparaison au modèle semi-distribué, la possibilité d’examiner les voies d’écoulement en tout point de l’aquifère en 3D est démontrée, ce qui peut donner de nouvelles connaissances sur les écoulements (et le transport potentiel de contaminants) au sein de tels systèmes complexes. L’influence de la proximité de conduits hautement transmissifs sur les écoulements dynamiques au travers des cellules de transmissivité plus faible de la matrice au sein de laquelle le réseau est intégré, a été particulièrement étudiée.Se han elaborado varios enfoques diferentes para modelar las características específicas de los acuíferos kársticos, teniendo en cuenta sus complejas y propias heterogeneidades espaciales y temporales. En el presente documento se expone la elaboración de un enfoque de modelización semidistribuido para aplicaciones en un contexto kárstico de Irlanda utilizando programas informáticos de drenaje urbano. Los modelos han demostrado ser muy útiles para diferentes estudios, y se dan ejemplos para la ecohidrología de los lagos kársticos efímeros, la mitigación de las inundaciones extremas de aguas subterráneas, la investigación de redes kársticas, la descarga submarina de aguas subterráneas y la cuantificación de diferentes componentes de la recarga y el flujo. También se ponen de relieve las limitaciones del enfoque, en particular el hecho de no poder simular explícitamente la infiltración difusa y las trayectorias de flujo a través de la cuenca de captación de aguas subterráneas. Por lo tanto, un enfoque de modelización de diferencias finitas distribuidas utilizando la red no estructurada (USG) de MODFLOW con el proceso de la Red Lineal Conectada (CLN) recientemente desarrollado se compara entonces con el enfoque semidistribuido en la misma cuenca kárstica. Si bien se ha demostrado que es difícil lograr los mismos niveles de rendimiento del modelo en la simulación de los flujos de manantiales en el modelo distribuido en comparación con el modelo semidistribuido, se demuestra la capacidad de interrogar las trayectorias de los flujos en cualquier punto del acuífero tridimensional, lo que puede dar nuevos conocimientos sobre los flujos (y el transporte de contaminantes potenciales) a través de sistemas tan complejos. Se ha investigado en particular la influencia de la proximidad de conductos altamente transmisivos en la dinámica de los flujos a través de las células de la matriz transmisiva, mucho más bajas, en las que está incorporada la red.鉴于岩溶含水层内在的复杂时空异质性, 已经开发出几种不同的方法来模拟岩溶含水层的特定性质。本文提出了基于城市排水软件的半分布式模型的开发方法, 并在爱尔兰喀斯特环境中应用。该模型已被证明对不同的研究非常有用, 并举例说明了季节性的喀斯特湖的生态水文学, 极端地下水洪涝减缓, 岩溶网络调查, 海底地下水排泄以及不同补给量和流动量的量化。还强调了该方法的局限性, 特别是不能明确模拟整个地下水盆地的扩散入渗和流动路径。因此, 然后将MODFLOW非结构化网格(USG)和新开发的连接线性网络(CLN)过程耦合的分布式有限差分方法与同一个喀斯特流域的半分布式方法进行了比较。尽管已证明分 布式模型模拟的泉流量难以达到与半分布式模型相比相同水平的模型性能, 但仍展示了在三维含水层上任意点处查询流路的能力, 这可以给出分析该类复杂系统流量(以及潜在的污染物传输)的新方法。特别研究了高传输管流的邻近度对通过嵌入网络的传导率低得多单元的流动动力学的影响。.Diversas abordagens diferentes foram desenvolvidas para modelar as características específicas dos aquíferos cársticos, levando em consideração suas complexas heterogeneidades espaciais e temporais inerentes. Este artigo apresenta o desenvolvimento de uma abordagem de modelagem semidistribuída para aplicações em um contexto cárstico irlandês usando software de drenagem urbana. Os modelos provaram ser muito úteis para diferentes estudos, com exemplos dados para a ecohidrologia de lagos cársticos efêmeros, alívio de inundações subterrâneas extremas, investigação de rede cárstica, descarga de água subterrânea submarina e quantificação de diferentes componentes de recarga e fluxo. As limitações da abordagem também são destacadas, em particular não ser capaz de simular infiltração difusa e caminhos de fluxo explicitamente através da captação de água subterrânea. Portanto, uma abordagem de modelagem de diferenças finitas, mais distribuída, usando MODFLOW Unstructured Grid (USG) com o processo de Rede Linear Conectada (RLC) recém-desenvolvido é então comparada com a abordagem semidistribuída na mesma bacia cárstica. Embora tenha se mostrado difícil alcançar os mesmos níveis de desempenho do modelo na simulação dos fluxos de nascente no modelo distribuído em comparação com o modelo semidistribuído, a capacidade de interrogar os caminhos de fluxo em qualquer ponto do aquífero tridimensional é demonstrada, o que pode dar novas percepções sobre os fluxos (e o transporte potencial de contaminantes) por meio de tais sistemas complexos. A influência da proximidade de condutos altamente transmissivos na dinâmica do fluxo através das células da matriz transmissiva muito inferior nas quais a rede está inserida foi investigada particularmente.
- Published
- 2020
23. 鄂尔多斯盆地陇东地区构造特征及其对古生界 铝土岩气藏的控制作用.
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杜广宏, 姚泾利, 张盟勃, 侯 芳, 瞿 长, and 张 三
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NATURAL gas prospecting ,GAS reservoirs ,BAUXITE ,TOPOGRAPHY ,KARST ,GEOMORPHOLOGY - Abstract
Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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24. Differential Characteristics of Conjugate Strike-Slip Faults and Their Controls on Fracture-Cave Reservoirs in the Halahatang Area of the Northern Tarim Basin, NW China.
- Author
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Wang, Shenglei, Chen, Lixin, Su, Zhou, Dong, Hongqi, Ma, Bingshan, Zhao, Bin, Lu, Zhendong, and Zhang, Meng
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FAULT zones ,KARST ,STRIKE-slip faults (Geology) ,WEATHERING - Abstract
The X-type strike-slip fault system and weathering crust karst fracture-cave and channel reservoirs were developed in the Halahatang area of the northern Tarim Basin. However, the relationship between the reservoir and the strike-slip fault remains controversial. Based on the core data, and taking an NE-striking strike-slip fault as an example, this paper dissects the karst reservoir from wells along the strike-slip fault damage zone and analyzes the control of scales, properties, and segmentation styles of strike-slip faults on karst reservoirs. The results show that (1) the scale of the strike-slip fault controls the distribution of the reservoir—the wider the fault damage zone, the wider the fracture-cave reservoirs; (2) the transtensional segments of the strike-slip fault are more likely to produce karstification, and the buried-hill area and the interbedded area are controlled by different hydrodynamic conditions to form different types of karst reservoirs; (3) six different parts of the strike-slip fault are conducive to the formation scale of fault fracture zones. This research provides new insight into recognizing karst reservoirs within strike-slip fault damage zones, which can be further applied to predict karst reservoirs controlled by strike-slip faults. [ABSTRACT FROM AUTHOR]
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- 2024
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25. The Characteristics and Application of Deuterium and Oxygen Isotopes to Karst Groundwater, Southwest China.
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Tang, Mi, Yu, Shi, You, Shaohong, and Jiang, Pingping
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STABLE isotopes ,KARST ,GROUNDWATER recharge ,DEUTERIUM ,OXYGEN isotopes ,GROUNDWATER ,HYDROLOGIC cycle ,BODIES of water - Abstract
Stable isotopes in natural water bodies serve as hydrologic tracers, with a history of extensive application in karst groundwater research. The present paper is a systematic review of previous research results, with the objective of sorting out and summarizing the stable isotopic characteristics of karst groundwater in southwest China, which is the most typical karst region worldwide. Comprehensive analysis reveals that the deuterium and oxygen isotope values of most karst groundwater are characterized temporally as 'enriched in the rainy season and depleted in the dry season', which is the opposite of the pattern of precipitation. While the spatial distribution feature is basically consistent with the spatial variation pattern of precipitation, which is characterized as 'depleted from the coast to the interior'. Additionally, the main applications of stable isotopes to karst groundwater are discussed, including karst groundwater recharge source and recharge elevation identification, research on karst groundwater in the hydrological cycle, the hydrological process of karst groundwater, and karst groundwater contamination tracking. Finally, we looked forward to future research on karst groundwater based on deuterium and oxygen isotopes. It is our hope that this review may provide insight into the study of karst groundwater. [ABSTRACT FROM AUTHOR]
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- 2024
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26. Remote sensing inversion study of total organic carbon concentration in Karst Plateau Lakes-Taking Pingzhai reservoir as an example.
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Rukai Xie, Zhongfa Zhou, Jie Kong, Yan Zou, Fuqiang Zhang, Li Li, Yanbi Wang, Cui Wang, and Caixia Ding
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REMOTE sensing ,OPTICAL remote sensing ,WELLHEAD protection ,KARST ,REMOTE-sensing images ,WATER quality ,BODIES of water - Abstract
Currently, the inversion of remote sensing satellite images of water environment indicators mostly stays in the indicators with active optical characteristics, while there is less research on the inversion of most water quality indicators with non-optical activity properties, weak scattering and absorption of optical radiation, the size of their concentration has little effect on the spectral characteristics of the water body, such as TOC(Total Organic Carbon). In this paper, based on Pingzhai Reservoir, a dammed river in the karst mountainous area, the inversion model of TOC concentration was established based on BP neural network (BPNN) and sentinel-2 satellite remote sensing images. The results showed that the single bands with high correlation with the measured TOC concentration data were two vegetation red-edge bands B6 (740 nm) and B7 (783 nm) and one NIR band B8 (842 nm), and finally b7, b6 + b7, b7 + b8, b7 ×b8 were selected as the input layers of BPNN for modeling through the combination of the bands, and their Pearson's coefficients were -0.667, -0.656, -0.655, - 0.675. The inverse model established could reach a minimum RMSE of 0.235 mg/L and a maximum R2 of 0.889, which was superior to that of the conventional empirical model. Demonstrate the feasibility of a TOC inversion method based on Sentinel-2 data and BPNN to monitor TOC concentrations in Pingzhai Reservoir. The study successfully established a BP neural network inversion model of TOC concentration in Pingzhai Reservoir with low error, meanwhile, we analyzed the correlation between common water quality indicators and TOC in the reservoir, in which TOC showed significant positive correlation with WT and significant negative correlation with TN and EC, with Pearson's coefficients of 0.655, -0.666, and -0.393, respectively. The article provides scientific theoretical foundation and technical support for water quality protection of water sources. [ABSTRACT FROM AUTHOR]
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- 2024
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27. Using Wavelet Coherence to Characterize Surface Water Infiltration into a Low‐Lying Karst Aquifer
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Paul Johnston, Lea Duran, Laurence Gill, Philip Schuler, and Èlia Cantoni
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0208 environmental biotechnology ,Soil science ,Aquifer ,02 engineering and technology ,STREAMS ,Rivers ,Water Movements ,Computers in Earth Sciences ,Groundwater ,Water Science and Technology ,geography ,geography.geographical_feature_category ,Water ,Research Papers ,Groundwater recharge ,Karst ,6. Clean water ,020801 environmental engineering ,Water level ,Complex dynamics ,Infiltration (hydrology) ,13. Climate action ,Environmental science ,Hydrology ,Surface water ,Research Paper - Abstract
Karstified carbonate aquifers may receive significant recharge contributions from losing streams, hence, the knowledge about surface water‐groundwater (SW‐GW) interactions is crucial with regard to water management (e.g., source protection zone delineation). The dynamics of SW‐GW interactions may depend on factors such as the relative water levels between streams and aquifers, resulting in a temporal variation of exchange, which imposes complexity to the understanding of such dynamics. This study highlights the use of high‐resolution time series and multiresolution analysis to help to gain insights into such complex dynamics. Wavelet coherence is applied on hourly time series of rainfall, stream, and spring discharges of a low‐lying karstified spring catchment to yield a correlation in the time‐frequency domain. This analysis provides comprehensive information on the overall impact of the river on the spring, which is supported by the cross‐correlation function, as well as by more detailed information, including time‐variant influences such as a threshold level of influence. Field observations of turbidity sampling at the spring appear to support this interpretation. This innovative approach relies on basic hydrological parameters, water level, or discharge, and is therefore applicable to many other systems with such existing time series., Article impact statement: Wavelet coherence yields high‐resolution information on surface water‐groundwater interaction.
- Published
- 2020
28. Habitat use, roost selection and conservation of bats in Tsingy de Bemaraha National Park, Madagascar
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Kofoky, Amyot, Andriafidison, Daudet, Ratrimomanarivo, Fanja, Razafimanahaka, H. Julie, Rakotondravony, Daniel, Racey, Paul A., Jenkins, Richard K. B., Hawksworth, David L., editor, and Bull, Alan T., editor
- Published
- 2007
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29. Model aided quantification of dissolved carbon and nitrogen release after windthrow disturbance in an Austrian karst system.
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Hartmann, A., Kobler, J., Kralik, M., Dirnböck, T., Humer, F., and Weiler, M.
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WINDFALL (Forestry) ,DRINKING water ,NITROGEN in water ,WATER supply ,CARBON content of water ,CLIMATE change ,KARST - Abstract
Karst systems are important for drinking water supply. Future climate projections indicate increasing temperature and a higher frequency of strong weather events. Both will influence the availability and quality of water provided from karst regions. Forest disturbances such as windthrow can disrupt ecosystem cycles and cause pronounced nutrient losses from the ecosystems. In this study, we consider the time period before and after the wind disturbance period (2007/08) to identify impacts on DIN (dissolvedinorganic nitrogen) and DOC (dissolved organic carbon) with a process-based flow and solute transport simulation model. Calibrated and validated before the disturbance the model disregards the forest disturbance and its consequences on DIN and DOC production and leaching. It can therefore be used as a base-line for the undisturbed system and as a tool for the quantification of additional nutrient production. Our results indicate that the forest disturbance by windthrow results in a significant increase of DIN production lasting 3.7 years and exceeding the pre-disturbance average by 2.7 kg ha
-1 a-1 corresponding to an increase of 53%. There were no significant changes of DOC concentrations. With simulated transit time distributions we show that the impact on DIN travels through the hydrological system within some months. But a small fraction of the system outflow (< 5%) exceeds mean transit times of > 1 year. [ABSTRACT FROM AUTHOR]- Published
- 2015
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30. Karst bare slope soil erosion and soil quality: a simulation case study.
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Dai, Q., Liu, Z., Shao, H., and Yang, Z.
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SLOPES (Soil mechanics) ,KARST ,SOIL erosion ,RAINFALL ,SOIL quality - Abstract
The influence on soil erosion by different bedrock bareness ratios, different rainfall intensities, different underground pore fissure degrees and rainfall duration are researched through manual simulation of microrelief characteristics of karst bare slopes and underground karst crack construction in combination with artificial simulation of rainfall experiment. The results show that firstly, when the rainfall intensity is small (30 and 50 mm h
-1 ), no bottom load loss is produced on the surface, and surface and underground runoff and sediment production is increased with the increasing of rainfall intensity; secondly, surface runoff and sediment production reduced with increased underground pore fissure degree, while underground runoff and sediment production increased; thirdly, raindrops hit the surface, forming a crust with rainfall duration. The formation of crusts increases surface runoff erosion and reduces soil infiltration rate. Increasing of surface runoff erosion damaged crust and increased soil seepage rate. Raindrops continued to hit the surface, leading the formation of crust. Soil permeability showed volatility which were from reduction to increases and reduction, and so on. Surface and subsurface runoff were volatility with rainfall duration; fourthly, when rock bareness ratio is 50% and rainfall intensities are 30 and 50 mm h-1 , runoff is not produced on the surface, and the slope runoff and sediment production presents a fluctuating change with increased rock bareness ratio; fifthly, the correlation degree between the slope runoff and sediment production and all factors are as follows: rainfall intensity > rainfall duration > underground pore fissure degree > bed rock bareness ratio. [ABSTRACT FROM AUTHOR]- Published
- 2015
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31. Water consumption prediction and influencing factor analysis based on PCA-BP neural network in karst regions: a case study of Guizhou Province.
- Author
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Yang, Zhicheng, Li, Bo, Wu, Huang, Li, MengHua, Fan, Juan, Chen, Mengyu, and Long, Jie
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WATER consumption ,WATER management ,FACTOR analysis ,KARST ,PRINCIPAL components analysis ,WATER supply - Abstract
Water consumption prediction is an integral part of water resource planning and management. Constructing a highly precise water consumption prediction model is of great significance for promoting regional water resource planning and high-quality development of the socio-economy. This paper focuses on the case of the typical karst region in Guizhou Province in China. Based on data on water consumption and its influencing factors spanning 2000–2020, the principal component analysis method was applied to reduce the dimensionality of 16 influencing factors of water consumption in Guizhou; the principal components extracted were used as input samples of the BP neural network and a PCA-BP neural network water consumption prediction model was conducted to predict water consumption of Guizhou Province in the next 10 years. The results show that the mean absolute error and mean relative error of prediction based on the constructed PCA-BP neural network were 2.8% and 2.9%, respectively, with superior performance in terms of prediction error and trends compared with other models. This paper discusses the main influencing factors of water consumption and analyzes their influence on the water consumption forecasting model so that the parameters of the water consumption forecasting model can be selected more efficiently and provide a reference for regional water consumption analysis and water resource planning and management. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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32. Seismic Response and Damage Analysis of Shield Tunnel with Lateral Karst Cavity under Oblique SV Waves.
- Author
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Li, Mingda, Meng, Kang, and Zhou, Jing
- Subjects
SEISMIC response ,TUNNEL design & construction ,TUNNELS ,KARST ,SEISMIC waves ,FINITE element method ,SURFACE waves (Seismic waves) ,EARTHQUAKE resistant design - Abstract
The dynamic effects of the lateral karst cavity on the shield tunnels under different incident angles of seismic waves are investigated by numerical analysis in this paper, based on the Dalian Metro Line 5 project. The viscous-spring artificial boundary is applied and verified to guarantee the accuracy of seismic input. A simplified finite element model of shield tunnel is established based on the equivalent bending stiffness model. This paper compares the seismic response characteristics and damage states of the tunnel under different incident angles by analyzing the axial deformation, stress distribution, and damage severity, respectively. A new damage state classification criterion is proposed by introducing the relationship between cracks and tensile damage. The results show that the tunnel's affected scope by the lateral karst cavity is twice the cavity diameter. As the incident angle increases, the tunnel's displacement and stress increase and show the structural spatial difference, and the tunnel's damage state is increasingly severe. The displacement and stress reach the max values when the incident angle is 30°. The cracks along the axial direction extend on the outer surface of the vault and bottom, and the crack width is greater than 0.2 mm, as that angle is 30°. The damage severity at the tunnel's central zone is minimum along axial directions during seismic action, while the damage concentration occurs on the bottom at the end of seismic. The lateral karst cavity plays an energy dissipation and vibration reduction role to a certain extent, but it also aggravates the local damage. This paper can serve as a reference for the seismic design of tunnels in karst regions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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33. A Commented Review of Eco-Product Value Realization and Ecological Industry and Its Enlightenment for Agroforestry Ecosystem Services in the Karst Ecological Restoration.
- Author
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Yang, Ying, Xiong, Kangning, Huang, Huiqiong, Xiao, Jie, Yang, Biliang, and Zhang, Yu
- Subjects
VALUE (Economics) ,RESTORATION ecology ,ECOSYSTEM services ,KARST ,AGROFORESTRY ,ECOLOGICAL regions - Abstract
The achievement of eco-product value and the growth of eco-industry can boost the economic advancement of karst areas. The findings of a statistical analysis of 520 relevant studies reveal the following: (1) From a time series perspective, the amount of papers increase with each wave of research; (2) contents mainly concentrate on four aspects, namely, ecosystem services supply (8.46%), value accounting (10.58%), value realization (37.88%), and eco-industry (30.38%); (3) the study areas are primarily concentrated in Asia (85.96%), Europe (7.12%), and North America (4.04%), most of which are located in China's karst areas with vulnerable ecological environments and regions that are aware of eco-product values; and (4) research frontiers are reflected through four aspects of the ecosystem, namely, services supply, value accounting, value realization, and the eco-industry. Based on the analysis in this paper, it can be concluded that paths, mechanisms, and models for eco-product value realization are still slow. Therefore, to support the growth of karst agroforestry ecosystem services, it is imperative to further research the capacity of agroforestry ecosystem services supply, value accounting systems, ecological compensation mechanisms, the value realization models of eco-products, and the formation mechanism of eco-industries. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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34. Effects of vegetation restoration on the aggregate stability and distribution of aggregate-associated organic carbon in a typical karst gorge region.
- Author
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Tang, F. K., Cui, M., Lu, Q., Liu, Y. G., Guo, H. Y., and Zhou, J. X.
- Subjects
CARBON compounds ,KARST ,SOIL structure - Abstract
Changes in soil utilization significantly affect aggregate stability and aggregateassociated soil organic carbon (SOC). A field investigation and indoor analysis were conducted in order to study the soil aggregate stability and organic carbon distribution in the water-stable aggregates (WSA) of the bare land (BL), grassland (GL), shrubland (SL), and woodland (WL) in a typical karst gorge region. The results indicated that the BL, GL, SL, and WL were dominated by particles with sizes > 5mm under dry sieving treatment, and that the soil aggregate contents of various sizes decreased as the particle size decreased. In addition, the BL, GL, SL, and WL were predomi nantly comprised of WSA< 0.25mm under wet sieving treatment, and that the WSA contents initially increased, then decreased, and then increased again as the particle size decreased. Furthermore, at a soil depth of 0-60 cm, the mean weight diameter (MWD), geometrical mean diameter (GMD), and fractal dimensions (D) of the dry aggregates and water-stable aggregates in the different types of land were ranked, in descending order, as WL>GL>SL>BL. The contents of WSA> 0.25mm, MWD and GMD increased significantly, in that order, and the percentage of aggregate destruction (PAD) and fractal dimensions decreased significantly as the soil aggregate stability improved. The results of this study indicated that, as the SOC contents increased after vegetation restoration, the average SOC content of WL was 2.35, 1.37, and 1.26 times greater than that in the BL, GL, and SL, respectively. The total SOC and SOC associated in WSA of various sizes were the highest at a soil depth of 0-20 cm. In addition, the SOC contents of the WSA increased as the soil aggregate sizes decreased. The SOC contents of the WSA< 0.25mm were highest except in the bare land, and the SOC contents of the aggregates < 0.25 mm, which ranged from 18.85 to 41.08 %, com prised the majority of the total aggregate SOC contents. The woodland and grassland facilitated WSA stability and SOC protection, thus, promoting the natural restoration of vegetation by reducing artificial disturbances could effectively restore the ecology of and prevent soil erosion in karst regions. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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35. Hydrogeochemical Characteristics and Evolution Processes of Karst Groundwater Affected by Multiple Influencing Factors in a Karst Spring Basin, Eastern China.
- Author
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Gao, Shuai, Li, Changsuo, Liu, Yuanyuan, Sun, Bin, Zhao, Zhiqiang, Lv, Minghui, and Gang, Shiting
- Subjects
KARST ,ENVIRONMENTAL research ,ECONOMIC conditions in China ,GROUNDWATER ,SEWAGE ,ENVIRONMENTAL protection - Abstract
Karst groundwater is an important water supply, especially in northern China. With the rapid development of China's economy, anthropogenic activities have had a significant impact on karst groundwater formation, circulation and other processes. In this paper, the Baotu spring basin, which is closely related to anthropogenic activities, was selected as the research object to carry out a study of water chemical characteristics and evolutionary processes. And, mathematical statistics, Piper trilinear diagram, Gibbs diagram, and ion ratio methods were used to analyze the characteristics and evolution processes of groundwater. The results of this study show that the hydrogeochemical components of karst groundwater are mainly controlled by the weathering of rocks, mainly by the dissolution of carbonate rocks and silicates with the dominant cation of Ca
2+ and the dominant anion of HCO3 − . Considering the role of anthropogenic activities, including agricultural and industrial activities, the evolution process of karst groundwater is mainly controlled by hydrogeochemical effects such as mineral dissolution and filtration, the mixing of multiple water bodies, anthropogenic activities (domestic sewage, industrial and agricultural wastes), oxidation–reduction and cation alternating adsorption. Moreover, the influence of anthropogenic activities on the formation and evolution of karst groundwater gradually increases, leading to the rise in nitrate content in karst groundwater and accelerating carbonate rock dissolution. The research results of this paper can provide a favorable reference for environmental protection and research on karst groundwater in areas of intensive anthropogenic activity. [ABSTRACT FROM AUTHOR]- Published
- 2023
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36. Divergent Geochemical Pathways of Carbonate Aquifer Evolution in a Classic Karst Terrain: (2) Groundwater Source Delineation Using Regional Water Chemistry Data.
- Author
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Burgess, Sarah Asha, Branam, Tracy D., and Florea, Lee J.
- Subjects
WATER chemistry ,KARST ,AQUIFERS ,GROUNDWATER ,WATER use ,AQUIFER pollution - Abstract
Springs provide ideal monitoring points for groundwater chemistry, which are important for managing groundwater resources. The chemistry of these spring waters aggregate geochemical reactions along the flow path. In this paper, part two of a two-part investigation, 104 perennial springs in the classic karst landscape of the Mitchell Plateau, Indiana, USA were sampled at base flow. Many of these springs are historically important for domestic, agricultural, commercial, and recreational use. Multifactor analysis of field measurements, principal ions, and stable isotopes revealed five primary clusters of springs emerging from the Mitchell Aquifer. Two clusters represented earth-alkaline-type karst groundwater that were discriminated by temperature and inorganic carbon concentration. Two other clusters comprised mineralized alkaline-earth-type groundwater with excess alkalis and elevated sulfate. The fifth cluster appeared to be groundwater that included meteoric and mineralized sources. Using the longitudinal data over two years from part one of this investigation, two mixing lines were used to describe the data set. The mixing lines pointed to sources of sulfur in mineralized springs from deep brines and from evaporite dissolution. Collectively, these regional data allow for a better delineation of water types and differentiation between the Upper and Lower Mitchell Aquifer. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
37. Analysis of Fouling Pattern of Tunnel Drainage Pipe in Karst Areas.
- Author
-
Lv, Jianbing, Wu, Hao, Li, Jia, Wan, Xiaodong, and Fu, Helin
- Subjects
DRAINAGE pipes ,DRAINAGE ,TUNNEL lining ,GROUNDWATER flow ,KARST ,TUNNELS - Abstract
As the groundwater in karst areas is rich in calcium ions, when the groundwater flows out of the tunnel drainage pipe, calcium carbonate crystals will be precipitated and then adhere to the pipe wall, which will easily cause chemical blockage in the drainage pipe wall, thus affecting the drainage efficiency and leading to the increase of water pressure outside the tunnel lining, affecting the safety and stability of the structure. Therefore, the blockage of calcium carbonate crystals in tunnel drains is one of the most important problems for the safe and normal operation of tunnels. In order to quantify and qualify the process of crystalline blockage in the drainage system of tunnels in karst areas, this paper constructs a numerical model with coupled multiphysical fields of the flow field and particle concentration field and also combines data from indoor tests to compare and verify the simulation results and analyze the time-varying law of crystalline solids deposited on the pipe wall. In this paper, we consider the force situation of crystalline solids in the pipe by water flow, analyze the related theories, comprehensively study the migration and deposition law of crystalline particles in the drainage pipe, and establish a numerical simulation model of the pipe crystallization rate considering temperature, flow velocity and concentration of sediment particles based on ANSYS FLUENT software, and refine and analyze several parameters in the model, so that it can provide a theoretical analysis framework for the tunnel drainage pipe blockage in karst areas by providing a theoretical analysis framework. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. A contribution to the understanding of the discharge dynamics and water balance of the karst spring Gornji Dušnik (Suva Planina).
- Author
-
Tanasković, Aleksandar, Vakanjac, Vesna Ristić, Polomčić, Dušan, and Močević, Jelena
- Subjects
KARST ,WATER springs ,WATER supply - Abstract
A sufficiently long time-series of daily discharges is needed to assess the discharge dynamics and calculate the water balance equation parameters of a spring (river source). The paper assumes that a catchment is gauged if a time-series of observations of at least 30 years is available, which is a rare case in Serbia. One-year monitoring is often set up to verify the reserves of a water source or spring intended for capture. Monitoring ceases after the final report is produced. The paper aims to show potential problems if there are no sufficiently long time-series and if no detailed hydrogeological investigations have been undertaken. The Gornji Dušnik Spring is used as an example. That spring drains the western parts of Suva Planina Mountain. It was captured many years ago to provide public water supply to the town of Gadžin Han and the nearby villages of Donji Dušnik and Gornji Dušnik. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
39. Theosbaena loko sp. n. a new stygobiotic microshrimp (Thermosbaenacea: Halosbaenidae) from southern Thailand
- Author
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Koraon Wongkamhaeng, Sopark Jantarit, and Rueangrit Promdam
- Subjects
0106 biological sciences ,Arthropoda ,Biodiversity & Conservation ,Nephrozoa ,010607 zoology ,Protostomia ,Zoology ,Circumscriptional names of the taxon under ,010603 evolutionary biology ,01 natural sciences ,Eumalacostraca ,taxonomy ,Cave ,subterranean hab ,Halosbaenidae ,Thermosbaenacea ,Genus ,Crustacea ,Animalia ,Bilateria ,subterranean habitats ,Malacostraca ,peninsular Thailand ,lcsh:QH301-705.5 ,Ecology, Evolution, Behavior and Systematics ,Telson ,new species ,geography ,geography.geographical_feature_category ,Ecology ,biology ,Cephalornis ,Thailand ,biology.organism_classification ,Karst ,Crustacean ,Theosbaena ,Peracarida ,lcsh:Biology (General) ,Notchia ,Paradiastylis whitleyi ,Ecdysozoa ,Conservation status ,Taxonomy (biology) ,Taxonomic Paper ,Cambodia ,Coelenterata - Abstract
Thermosbaenaceans (Thermosbaenacea: Halosbaenidae) are crustaceans, widespread, and occur in various habitats, including oligohaline or anchialine caves, freshwater, thermal springs, or cold waters. Currently, four families, seven genera, and 45 species are recognized worldwide. During the observation in an isolated limestone of Tham Loko (Loko Cave), Khao Chiason District, Phatthalung Province, the Theosbaena loko n. sp. were found. Theosbaena is the only genus reported in the oriental region. There are only two known species, namely Theosbaena cambodjiana Cals & Boutin 1985 from Kampot province, southern Cambodia, and T. kiatwongchai Rogers & Sanoamuang 2016 discovered in a cave of Takhli district, Nakhon Sawan province, central Thailand. Theosbaena loko n. sp. is the third species recorded in the oriental region.A new species Theosbaena loko n. sp. is described from a limestone cave in Phatthalung province, southern Thailand. The new species differs from its congener by having a telson, 1.8 longer than its breadth, maxilla 1 palp distal segment 4 times longer than the proximal palpomere, and the maxillopodal exopod twice as long as its basal width. This micro shrimp is the third described species of the genus known from Thailand and the Oriental region. A key to the species is given and suggestions for the conservation status of the new species are discussed.
- Published
- 2020
40. Large-Scale Mapping of the Historical Underground Limestone Quarries Using Mobile Laser Scanning, a Case Study in Riemst, Belgium.
- Author
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Lahaye, Mike Franciscus Aliene and De Kock, Tim
- Abstract
The cross-border Krijtland region in Belgium and the Netherlands encloses hundreds of historical underground limestone quarries. The municipality of Riemst, Belgium, is used as a case study because of the high density of underground quarries found there, and which are prone to frequent collapses related to the historical underground exploitation. As not all underground quarries have been mapped, a mobile laser scanner has been employed to aid the mapping surveys. This paper investigates how this method and its data can be used in the field of geoheritage and safety studies of underground quarries. The mobile laser scanner is an effective tool in mapping the vast underground networks, as well as georeferencing and mapping underground voids that are inaccessible for normal surveyors using a total station. The large amount of data, obtained by various surveys provides a high level of detail in which different structures and features can be identified. The results demonstrate the presence of different typologies of entrances, gallery morphologies and outlines in various underground quarries. It also appears to be a valuable tool in visualizing and identifying geological and stability features, such as karst, pillar instability and collapse areas. It can be concluded that in the field of safety management and geoheritage studies a mobile laser scanner proves to be an efficient method for mapping, documenting the underground landscape and describing different structural elements of underground quarries. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. Revision of some opinions expressed in my 1942 paper
- Author
-
Anker Nielsen
- Subjects
geography ,geography.geographical_feature_category ,Peninsula ,Spring (hydrology) ,Period (geology) ,Glacial period ,Physical geography ,STREAMS ,Karst - Abstract
Many insects, mayflies, stone-flies and caddis-flies inhabiting fast flowing water in Holsten and the Danish peninsula Jylland (Jutland), and especially those living in spring brooks with a low summer temperature, have been considered as relicts from a period with a colder climate, sometimes even as Glacial relicts. In 1942 I published a paper, based on studies of streams in the province Himmerland in northern Jutland, a somewhat karstic area rich in large springs. In this paper (pp. 622–625 ) I reduced the number of relicts considerably, and pointed out that some of the spring inhabiting species might be relicts from the Atlantic Period in the Post Glacial, in which the winter is believed to have been warmer than nowadays. If so, they had survived in the springs due to the relatively high winter temperature of the latter. I now realize that I did not reduce the number nearly enough.
- Published
- 1976
42. A Review of Ecosystem Service Trade-Offs/Synergies: Enlightenment for the Optimization of Forest Ecosystem Functions in Karst Desertification Control.
- Author
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Deng, Xuehua, Xiong, Kangning, Yu, Yanghua, Zhang, Shihao, Kong, Lingwei, and Zhang, Yu
- Subjects
ECOSYSTEM services ,DESERTIFICATION ,KARST ,ECOSYSTEMS ,ENLIGHTENMENT ,EVALUATION methodology - Abstract
Ecosystem services provide regulation, provisioning, support, and cultural benefits for human survival, but it needs to be clarified how the trade-off/synergy relationships can be used to optimize function. Based on the Web of Science (WOS) and China National Knowledge Infrastructure (CNKI) databases, we collected 254 articles on the ecosystem trade-offs/synergies and functional optimization. Through a systematic review of the literature, this paper summarized the research progress and landmark achievements from three aspects: trade-offs/synergies, functional optimization, and evaluation methods. The results indicated the following: (1) In terms of the number of articles published, there were no reports before 2005; from 2006 to 2022, the annual number of published papers increased from 1 to 72, showing an overall growth trend year by year. This mainly includes three stages: initial (1970–2005), slow development (2005–2014), and rapid development (2014–2022). (2) In terms of research areas, focus was placed mainly on Asia, North America, and Europe, accounting for 40.47%, 25.55%, and 15.07% of all regions, respectively. (3) In the future, it is necessary to focus on scientific issues such as the improvement of forest ecosystem functions, the trade-off/synergy relationships between services, the scale of spatiotemporal research, and the driving factors and evaluation methods for the management of rocky karst desertification. The aim is to provide a theoretical basis to optimize the forest ecosystem service functions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
43. A combined-method approach to trace submarine groundwater discharge from a coastal karst aquifer in Ireland
- Author
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L. Stoeckl, Philip Schuler, C. Bunce, P.-A. Schnegg, and Laurence Gill
- Subjects
Paper ,Submarine groundwater discharge ,Coastal aquifer ,010504 meteorology & atmospheric sciences ,Groundwater flow ,Sinkhole ,0207 environmental engineering ,Aquifer ,02 engineering and technology ,01 natural sciences ,Earth and Planetary Sciences (miscellaneous) ,14. Life underwater ,020701 environmental engineering ,0105 earth and related environmental sciences ,Water Science and Technology ,Hydrology ,geography ,geography.geographical_feature_category ,Hydrogeology ,Remote sensing ,Karst ,6. Clean water ,Tracer test ,13. Climate action ,Submarine pipeline ,Bay ,Ireland ,Geology - Abstract
Knowledge about the hydraulic connections between submarine groundwater discharge (SGD) and its terrestrial coastal catchment is relevant with regard to the management of marine and coastal waters in karst areas. This study applies different methods and monitoring approaches to trace SGD between the Burren Limestone Plateau and Galway Bay in western Ireland, via an excavated sinkhole shaft and deep conduit. Areas of potential SGD were first delineated based on sea surface temperature anomalies using Landsat satellite images. Two fluorescent dyes and solid wood chips were then used as tracers. Solid wood chips were tested as potential means to circumvent the problem of high dispersion in the sea, impacting on the fluorescent dyes to yield readings below the detection limits. Sampling was conducted at 10 different terrestrial locations and in the sea at Galway Bay. Offshore sampling was conducted in transects over a period of four successive days onboard of a vessel using an automated field fluorometer and a conductivity-temperature-depth sensor. No wood chips were recovered in the sea but both fluorescent dyes were successfully sampled. The estimated travel times are in the order of 100 to 354 m/h, and localised tracer readings correlate well in space and time with low conductivity readings. By confirming hydraulic connections between the two karst features and Galway Bay, the study substantiates the hypothesised importance of Variscan veins with regard to regional groundwater flow in the region.Die Kenntnis hydraulischer Zusammenhänge zwischen untermeerischen Grundwasseraustritten und deren terrestrischen Küsteneinzugsgebieten ist für die Bewirtschaftung der Meeres- und Küstengewässer in Karstgebieten von Bedeutung. Diese Studie wendet verschiedene Methoden und Messansätze an, um untermeerische Grundwasseraustritte zwischen dem Burren Kalkstein Plateau und der Galway Bucht in Westirland über einen ausgegrabenen Dolinen-Schacht und eine tiefe Karströhre zu verfolgen. Meeresbereiche mit potenziellen Grundwasseraustritten wurden zuerst unter Verwendung von Landsat-Satellitenbildern auf Grundlage von Temperaturanomalien an der Meeresoberfläche abgegrenzt. Dann wurden zwei fluoreszierende Farbstoffe und Holzspäne als Tracer verwendet. Die Holzspäne wurden als Mittel zur Umgehung des Problems starker Dispersion im Meer getestet, welche sich potentiell auf die fluoreszierenden Farbstoffe auswirken, und in Messwerten unterhalb der Nachweisgrenze resultieren kann. Die Probenahme wurde an 10 verschiedenen terrestrischen Standorten und im Meer der Galway Bucht durchgeführt. Mit einem automatisierten Feldfluorometer und einer Leitfähigkeits-, Temperatur- und Tiefensonde wurden in den jeweiligen Meeressektoren Messungen über einen Zeitraum von vier aufeinanderfolgenden Tagen an Bord eines Schiffes durchgeführt. Zwar wurden im Meer keine Holzspäne zurückgewonnen, allerdings wurden beide Fluoreszenzfarbstoffe erfolgreich gemessen. Die geschätzten Fließzeiten liegen in der Größenordnung von 100 bis 354 m/h und lokalisierte Tracer-Messwerte korrelieren räumlich und zeitlich gut mit Messwerten geringerer Leitfähigkeit. Die Bestätigung der hydraulischen Verbindungen zwischen dem Kalksteinplateau und der Bucht von Galway bestärkt die Hypothese der Bedeutsamkeit von variszischen Adern für den regionalen Grundwasserfluss.La connaissance des connexions hydrauliques entre les zones de sorties d’eaux souterraines sous-marines et le bassin terrestre côtier attenant est pertinente pour la gestion des eaux marines et côtières en zones karstiques. Cette étude applique différentes approches méthodologiques et de suivi pour tracer la sortie d’eaux souterraines sous-marines entre le plateau calcaire de Burren et la baie de Galway en Irlande de l’Ouest, via une perte et un conduit profond. Les zones de sorties potentielles d’eaux souterraines sous-marines ont été délimitées dans un premier temps sur la base d’anomalies de température des eaux de mer en utilisant des images satellites Landsat. Deux traceurs fluorescents et des copeaux de bois ont été utilisés comme traceurs. Les copeaux de bois ont été utilisés comme moyen potentiel pour contourner les problèmes de dispersion élevée dans la mer, qui impactent les traceurs fluorescents et engendrent des concentrations sous les limites de détections. L’échantillonnage a été menée sur dix sites différents à terre et en mer dans la baie de Galway. L’échantillonnage en mer e a été mené selon des profils sur une période de quatre jours successifs à bord d’un navire muni d’un fluorimètre de terrain automatique et d’un capteur de conductivité-température-profondeur. Aucun copeau de bois n’a été récupéré en mer, mais les deux traceurs fluorescents ont été échantillonnés avec succès. Les temps de séjour estimés sont de l’ordre de 100 à 354 m/h, et les valeurs de traceurs localisées corrèlent bien en espace et en temps avec les basses valeurs de conductivité électrique. En confirmant les connexions hydrauliques entre les deux phénomènes karstiques et la baie de Galway, l’étude corrobore l’hypothèse de l’importance des veines du cycle varisque sur l’organisation des écoulements régionaux d’eau souterraine dans la région.El conocimiento de las conexiones hidráulicas entre la descarga submarina de aguas subterráneas (SGD) y su cuenca costera terrestre es relevante para la gestión de las aguas marinas y costeras en las zonas kársticas. Este estudio aplica diferentes métodos y enfoques de monitoreo para el seguimiento de la SGD entre la meseta de caliza de Burren y la bahía de Galway en el oeste de Irlanda, a través de un pozo excavado y un conducto profundo. Las áreas de SGD potenciales fueron delineadas primero basándose en anomalías de la temperatura de la superficie del mar usando imágenes satelitales Landsat. Dos tintes fluorescentes y astillas de madera maciza se utilizaron como trazadores. Las astillas de madera maciza se probaron como medio potencial para eludir el problema de la alta dispersión en el mar, impactando en los colorantes fluorescentes para obtener lecturas por debajo de los límites de detección. El muestreo se llevó a cabo en 10 lugares terrestres diferentes y en el mar en la Bahía de Galway. El muestreo en alta mar se llevó a cabo en transectas durante un período de cuatro días consecutivos a bordo de un buque utilizando un fluorómetro de campo automatizado y un sensor de conductividad-temperatura-profundidad. No se recuperaron astillas de madera en el mar, pero se tomaron muestras exitosas de ambos tintes fluorescentes. Los tiempos de tránsito estimados son del orden de 100 a 354 m/h, y las lecturas del trazador localizadas se correlacionan bien en el espacio y el tiempo con las lecturas de baja conductividad. Al confirmar las conexiones hidráulicas entre las dos características kársticas y la Bahía de Galway, el estudio corrobora la importancia hipotética de las vetas de Variscan con respecto al flujo regional de agua subterránea en la región.在岩溶地区, 海底地下水排泄(SGD)与其陆地沿海集水区之间水力联系的认识与海洋和沿海水域的管理有关。本研究采用不同的方式和监测方法, 通过开挖的落水洞和深水管道来示踪爱尔兰西部Burren石灰岩高原和Galway湾之间的地下水排泄。首先利用Landsat卫星图像和基于海平面温度异常划定了潜在的SGD区域。然后将两种荧光染料和实木碎片用作示踪剂。测试了实木碎屑作为解决海洋中由于影响荧光染料使产生低于检测极限读数的高弥散问题的潜在手段。在Galway湾的10个不同陆面位置和海洋中进行了采样。使用自动现场荧光计和电导率-温度-深度传感器, 在船上连续四天的时间段内, 进行海洋取样。在海洋中没有回收木屑, 但两种荧光染料均已成功采样。估计的行程时间约为100至354 m/h, 局部示踪剂读数在空间和时间上与低电导率读数相关性很好。通过确定两个喀斯特地貌与Galway湾之间的水力联系, 该研究证实了华力西期脉对于该地区区域地下水流动的假设重要性。.O conhecimento sobre as conexões hidráulicas entre a descarga submarina de águas subterrâneas (DSAS) e sua captação terrestre na costa é relevante no que diz respeito ao gerenciamento de águas marinhas e costeiras em áreas cársticas. Este estudo aplica diferentes métodos e abordagens de monitoramento para rastrear a DSAS entre o platô de calcário de Burren e a baía de Galway, no oeste da Irlanda, por meio de um poço escavado e um conduto profundo. Áreas de potencial DSAS foram primeiramente delineadas com base em anomalias de temperatura da superfície do mar usando imagens do satélite Landsat. Dois corantes fluorescentes e lascas de madeira maciça foram então utilizados como marcadores. Lascas de madeira maciça foram testadas como um meio potencial para contornar o problema de alta dispersão no mar, impactando nos corantes fluorescentes para produzir leituras abaixo dos limites de detecção. A amostragem foi realizada em 10 locais terrestres diferentes e no mar na Baía de Galway. A amostragem fora da costa foi realizada em transectos durante um período de quatro dias sucessivos a bordo de uma embarcação usando um fluorômetro de campo automatizado e um sensor de condutividade-temperatura-profundidade. Nenhuma lasca de madeira foi recuperada no mar, mas os dois corantes fluorescentes foram amostrados com sucesso. Os tempos de viagem estimados são da ordem de 100 a 354 m/h, e as leituras localizadas do traçador se correlacionam bem no espaço e no tempo com as leituras de baixa condutividade. Ao confirmar as conexões hidráulicas entre as duas formações cársticas e a Baía de Galway, o estudo confirma a hipótese da importância das veias variscas em relação ao fluxo regional de águas subterrâneas na região.
- Published
- 2019
44. Planning tsunami vertical evacuation routes using high-resolution UAV digital elevation model: case study in Drini Coastal Area, Java, Indonesia
- Author
-
Annisa Dzikra Salma, Nurul Khakim, Muh Aris Marfai, and Hendy Fatchurohman
- Subjects
geography ,Original Paper ,geography.geographical_feature_category ,Java ,Meteorology ,Tsunami ,DEM ,High resolution ,Land cover ,computer.file_format ,Karst ,Gunungkidul ,Indonesia ,Least cost ,General Earth and Planetary Sciences ,Structure from motion ,Environmental science ,Raster graphics ,Digital elevation model ,computer ,Evacuation ,General Environmental Science ,computer.programming_language - Abstract
Tsunami evacuation is a short process that must be carried out in minutes. Determining the evacuation routes and safe areas is equally important in tsunami evacuation planning. It can be established from least cost distance (LCD) anisotropic model. We use the coastal of Drini, Gunungkidul, Java, Indonesia, as the study area, which is located in a tropical coastal karst region, with a typical karst cone formation. The topographic condition of the karst cone could be an ideal location for tsunami vertical evacuation (TVE). High-resolution orthomosaic images and digital elevation model (DEM) generated from the structure from motion (SfM) process were used as the main data. The tsunami inundation model was calculated based on neighboring operations using raster calculator from the elevation value in the DEM. Land cover identification from high-scale orthomosaic images showed the variation in speed conservation values (SCVs). The slope value was also used as a surface cost that will affect the travel time to the TVE shelters. The results of the model show that TVE is the main alternative in tsunami evacuation planning beside horizontal evacuation. They provide an evaluation of the location of the assembly points and evacuation routes provided by the government, which have been considered ineffective because of the inappropriate model. The results of the study provide an overview of determining the evacuation routes and shelters. Optimum locations can minimize travel time, provide adequate capacity, and be safe from inundation.
- Published
- 2021
45. Study on Anti-seepage Measures of Tunnel Construction Excavation Through Karst Area.
- Author
-
SU Kai, YANG Feng-jie, GONG Rui, and ZHU Hong-ze
- Subjects
SEEPAGE ,TUNNEL design & construction ,PORE water pressure ,WATER tunnels ,KARST ,WATER seepage - Abstract
It is very easy to encounter the phenomenon of water and mud gushing during construction and excavation of tunnel through karst area. How to choose appropriate anti-seepage measures to reduce the seepage flow of tunnel has always been a hot issue. In this paper, a three-dimensional finite element model of complex strata in karst area is established based on a water diversion project . Three anti-seepage measures, namely back-filling concrete on the roof of the tunnel, grouting ring around the tunnel and concrete cutoff wall, are mainly considered. The change law of pore water pressure and seepage flow of the tunnel during tunnel excavation is studied, and the influence of permeability coefficient of the cutoff wall and grouting ring on seepage characteristics is analyzed. The results show that the concrete cutoff wall has a great influence on the distribution of pore water pressure in the tunnel, the water level between the cutoff walls decreases obviously, and the grouting ring around the tunnel has the greatest influence on the seepage flow of the tunnel, and the quality of the grouting ring should be ensured during construction. The pore water pressure increases with the increase of the horizontal distance from the tunnel center, and increases first and then decreases with the increase of the vertical distance from the tunnel center. With the increase of the permeability coefficient of the grouting ring or the cutoff wall, the pore pressure growth rate in the area of the grouting ring or the wall decreases gradually, and the seepage flow of the tunnel increases continuously. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. Study on load-bearing behaviors of prestressed post-grouting tubular piles in the karst region of northern Fujian Province, China.
- Author
-
Huang, Lingjun, Gao, Rui, Chi, Jingou, Yan, Xiaocai, Weiming, Gong, and Qin, Wei
- Subjects
KARST ,BUILDING foundations ,POISSON'S ratio ,PRESTRESSED concrete beams ,EARTH sciences ,ARCHITECTURAL engineering ,STEEL pipe ,BRECCIA - Abstract
The karst that is dominated by medium-weathered limestone and caves with various spatial features is widely distributed in the northern Fujian Province. This paper discusses the load-bearing behaviors of post-grouting tubular piles in karst region of north Fujian Province with reference to the prestressed tubular piles adopted in the residential buildings of Haixi Comprehensive Trade City Phase II Project in Sanming City. The load-settlement curve, pile side friction resistance, and pile end resistance of tubular piles are analyzed by finite element numerical simulations and field static load tests. The load-bearing behaviors of prestressed tubular piles under karst geological conditions with two different spatial features are comparatively investigated, and the effectiveness of tubular pile reinforcement is verified by field settlement observation. The results reveal that the finite element numerical model can effectively simulate the tubular pile-soil interaction. The use of pile end post-grouting of prestressed tubular piles in the karst region can significantly increase their load-bearing capacities. The top settlements of grouted tubular piles under the maximum test load can be reduced by 16.8%-22.3% compared with these of ungrouted test piles, and the theoretical simulated ultimate load-bearing capacity can be increased by 27.3%. The adoption of pile end post-grouting technique can reduce the pile end displacement of tubular piles and improve the proportion of pile end resistance. Plastic-hard plastic breccia silty clay can be used as a bearing stratum for post-grouting to achieve excellent grouting performance. The bead-shaped karst caves are more unfavorable to the exertion of load-bearing capacity of the tubular piles than the karst caves filled with plastic-hard plastic breccia silty clay to which the piles have direct access. The field monitored average settlements of the 19# and 17# buildings under karst geological conditions with two different spatial features are -12.88 mm and -8.98 mm, respectively, both of which do not exceed the warning value, indicating that it is feasible for the project to adopt the pile end post-grouting technique of the tubular piles. The achievements of this study help to further reveal the load-bearing mechanism of this type of pile, which can provide a basis for its engineering design and construction optimization. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
47. Assessment and optimization of fracture-karst cave connectivity in horizontal well hydraulic fracturing of carbonate reservoirs.
- Author
-
Tiankui Guo, Mingkun Lv, Pandeng Luo, Xin Yang, Ming Chen, Dingwei Weng, Zhanqing Qu, and Yiwen Liu
- Subjects
CARBONATE reservoirs ,HYDRAULIC fracturing ,KARST ,SPELEOTHEMS ,CRACK propagation (Fracture mechanics) ,YOUNG'S modulus ,CARBONATE minerals - Abstract
The karst cave serves as the primary storage space in carbonate reservoirs. Simultaneously connecting multiple karst caves through hydraulic fracturing is key to the efficient development of carbonate reservoirs. However, there is lack of systematic research on the mechanisms and influencing factors of fracture propagation in carbonate rocks. This paper established models including karst cave models, single natural fracture-cave models, and multiple natural fracture-cave models based on the discrete lattice method. It thoroughly studied how geological and operational factors affect the fracture propagation and the connectivity of karst caves. The final step involved establishing a prototype well model and optimizing operation parameters. The research indicates that an increase in the Young's modulus and pore pressure of karst cave could facilitate hydraulic fracture connecting with caves. When the pore pressure is lower than that in the matrix, it will generate a repulsive effect on hydraulic fractures. The natural fracture along the hydraulic fracture path significantly facilitates the connection with caves. When the wellbore azimuth is less than 60°C, the fracture's diversion radius is small, and hydraulic fractures primarily connect with karst cave through natural fractures. When the wellbore azimuth exceeds 60°C, the fracture's diversion radius increases. Under the combined action of hydraulic fractures and natural fractures, the stimulated volume of the karst cave noticeably increases. Under the same liquid volume, increasing the injection rate could enhance the cave stimulated volume. Combining the findings from numerical simulation studies resulted in the development of a diagram that depicts the connectivity of karst caves, providing valuable insight for hydraulic fracturing operations in carbonate reservoirs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
48. The Diversity of Subterranean Terrestrial Arthropods in Resava Cave (Eastern Serbia).
- Author
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Vesović, Nikola, Deltshev, Christo, Mitov, Plamen, Antić, Dragan, Stojanović, Dalibor Z., Stojanović, Dejan V., Stojanović, Katarina, Božanić, Milenka, Ignjatović-Ćupina, Aleksandra, and Ćurčić, Srećko
- Subjects
CAVES ,CAVE animals ,PITFALL traps ,NUMBERS of species ,LITERARY sources ,ARTHROPODA - Abstract
The Balkan region is rich in limestone deposits, which have created one of the largest hotspots of subterranean biodiversity. This paper gives an overview of the diversity of subterranean terrestrial arthropods in Resava Cave in eastern Serbia. This cave is protected and has the status of a natural monument. At the same time, it is one of the most visited caves in Serbia and its surroundings. Our study comprises the results of three years of biospeleological investigations of the famous Serbian cave in combination with data from the few available literature sources on the arthropod fauna of the cave. The arthropod samples were collected both manually and with pitfall traps. A total of 107 arthropod species from the four major subphyla were registered in the cave: 66 species of Hexapoda, 27 species of Chelicerata, 11 species of Myriapoda and three species of Crustacea. For four troglobitic, 16 troglophilic and 87 trogloxenic species recorded in the cave, descriptions of their microhabitats and information on their distribution in the cave are given. Considering the medium size of Resava Cave and the lack of permanent water flow in the two main levels on the one hand, and the large number of arthropod species recorded on the other, the cave is relatively rich in hypogean terrestrial arthropod fauna compared to other caves in Serbia that have been biospeleologically studied so far. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. 喀斯特区乡村景观格局特征及优化思路研究.
- Author
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文疆回, 李瑞, and 高家勇
- Abstract
Copyright of Ecological Science is the property of Ecological Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
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50. Editorial: Spatial constraints on multiple dimensions of biodiversity.
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Cerasoli, Francesco, Brown, Bryan Lyle, Swan, Christopher, and Convey, Peter
- Subjects
BIOTIC communities ,SPATIAL ecology ,ECOSYSTEMS ,LYNX ,KARST ,BIODIVERSITY ,GROUNDWATER monitoring - Abstract
This article discusses the spatial constraints on multiple dimensions of biodiversity. It explores how different measures of biodiversity, such as species richness, compositional dissimilarity, and food-web complexity, change in response to environmental gradients, disturbances, and climatic shifts. The article highlights recent advances in ecological analyses, including virtual simulations and habitat suitability models, that help researchers understand the drivers behind biodiversity patterns. The research papers included in this article cover a range of ecosystems, including virtual landscapes, riverine networks, groundwater caves, and terrestrial habitats. Overall, the article expands our understanding of the spatial and environmental factors that shape biodiversity and emphasizes the importance of protecting biodiversity based on ecological knowledge. [Extracted from the article]
- Published
- 2024
- Full Text
- View/download PDF
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