Pregled bibliografske jedinice broj: 475893
Hydrocomplexity of karst regions
Hydrocomplexity of karst regions // Xth Kovacs Colloquium
Pariz, Francuska, 2010. (poster, međunarodna recenzija, neobjavljeni rad, ostalo)
Hydrocomplexity of karst regions
Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, neobjavljeni rad, ostalo
Xth Kovacs Colloquium
Mjesto i datum
Pariz, Francuska, 2-3.07.2010.
Karst hydrology; karst aquifer
Karst is defined as a terrain, generally underlain by limestone or dolomite, in which the topography is chiefly formed by the dissolving of rock, and which is characterised by sinkholes, sinking streams, closed depressions, subterranean drainage and caves. A wide range of closed surface depressions, a well-developed underground drainage system, and strong interaction between circulation of surface water and groundwater typify karst. Diversity is considered the main feature of karstic systems, which are known to change over time and in space so that an investigation of each system on its own is required. In karst terrains groundwater and surface water constitute a single dynamic system. Hydrocomplexity of a karst regions is enormous. The determination of the catchment boundaries and the catchment area is the starting point in all hydrologic analyses and one of the essential data that serve as the basis for all hydrologic calculations. It is always a very complex task, especially in karst. Groundwater exchanges with adjacent aquifers through underground piracy routes or inflows from surface streams and accumulations are common in karst. Consequently, only in exceptional cases surface (topographic or orographic) and subsurface (hydrologic or hydrogeologic) catchment boundaries coincide. The problem is complicated additionally with the time-variant hydrologic boundaries that are dependent on fluctuations of groundwater levels. In order to define exactly the hydrologic catchment boundaries, it is necessary to carry out extensive geologic, hydrologic and hydrogeologic investigations. Karst aquifers are generally continuous. However, numerous subsurface morphologic features in karst (caves, jamas, fractures, faults, impermeable layers etc) strongly influence the continuity of the aquifer, and commonly the aquifer does not function as a continuum in a catchment. One of the most important characteristics of karst aquifers is the high degree of heterogeneity in their hydraulic properties. Scale issues are particularly important for understanding and modelling karst water circulation. Vadose zone and karst aquifer are two-component systems in which the major part of storage is in the form of true groundwater in narrow fissures, where diffuse or laminar flow prevails. On the other hand, majority of water is transmitted through the karst underground by quick or turbulent flow in solutionally enlarged conduits. Interaction between the two above-mentioned types of flow is significant and permanently present. Possibilities for overcoming karst system complexity and doubts find in closed co-operation between hydrology and hydrogeology as well as with different branches of geosciences, and organisation of continuous and detailed monitoring and fieldwork. Hydrology and hydrogeology have a dual role as scientific disciplines and as bases for informed decision-making on important practical problems. At the same time, both of them have, very deep scientific interests and task and an extremely important role in practice. Karst hydrology and hydrogeology need all kinds of models and modelling, as well as the new scientific approaches, methods and technologies. In the same time it should be profoundly aware that they are only a useful tool but not a panacea. For complex karst systems, no single model can be all-embracing, so different models may be needed for different purposes, including explanation, prediction and control. The karst environment has very different characteristics than all other environments. Due to the fact that the appearance, storage and circulation of water in karst is significantly different than in other more homogenous and isotropic terrains, karst ecohydrology should develop original methods. Biological importance and particularities of karst is enormous. Most karst landforms are actually products of both biotic and abiotic processes operating concurrently in intricate interrelationships. The evolution of entire karst landscapes is thought to be biologically controlled through the interrelationships of vegetative cover, erosion, and dissolution rates. Subterranean karst ecosystems are sensitive to environmental changes that occur on the surface. The importance of maintaining biological diversity goes far beyond mere protection of endangered species and beautiful landscape. It is necessary to obtain a thorough understanding of how aquatic and terrestrial ecosystems function and interact in very complex, vulnerable and in time and space extremely dynamic karst systems. A karst basin is a clearly definable ecosystem with measurable surface inputs from sinking streams and rainfall infiltration, and measurable outputs at the resurgence. The surface and especially subterranean environment in karst provides a range of habitats with different chemical and biological processes. To biologists and ecologists, they are fragile ecosystems, hosting rare and endangered species. For geochemists, they are the route of rapid transport of contaminants. A karst ecohydrological approach means integration karst studies into a more general ecological, biological, hydrological, hydrogeological, geomorphological, and geochemical context. Works on karst ecohydrology brings the diverse perspective of ecologists and karst hydrologist and hydrogeologists together. Karstology can be defined as the science of integrating hydrological, geomorphological, hydrogeological, ecological, biological, chemical, socio-economics, political and all others processes over varied spatial and temporal scales in specific karst regions. Karstology can be understood as logical and effective holistic integration of many different approaches. Role of hydrology in karstology is of crucial importance. Till now karstology is generally part of geosciences community, but in the near future it should connect geosciences with social and humanitarian scientific and practical disciplines. Conducting a basic research of main topics in karstology is key for understanding the nature of karst and its processes. The goal is to understand the complex phenomena of karst ; the evolution of its surface and subsurface, the evolution and function of karst aquifers and karst ecosystems, the origins of karst terminology and the history of karst science. These researches provide knowledge for efficient protection of vulnerable karst environment and planning of human activities on karst. The need for better understanding the deep and long lasting mutual relationship between human activities and natural processes in karst terrains is of crucial importance. In order to achieve their real sustainable development, it is necessary to fill the gaps in understanding of hydrological and ecological behaviour.