| Julong Karst Caverns of Quyang located in the mountain area of western Baoding, Hebeiprovince. It is representative Karst Caverns in warm temperate zone of North China area. Thetype and sculpt of Karst landscape in the cave are both abundant and various. However,compared with other North China caves, which are more mature, the study on Julong KarstCaverns are relatively weak. In order to get a deep study on this issue, in August2012, wewent to Lingshan mountain area to carry through field geological and geomorphic survey,cave measurement and detection. Therefore, we obtain a large amount of preciousfundamental research data. Base on physiographic and geologic foundation and conditions,we analyze the coupling relationship between regional geological-geomorphic evolutions andpaleo-climatic changes, discuss the geologic, geomorphic, hydrologic, organic caveenvironment factor and dissect geomorphic feature and genesis of Julong Karst Caverns. Onaccount of all above study, aiming at the cave structure stability, cave landscape evolution,cave resources development and conservation, we put forward some proposals. Maincognitives are as follows:(1) The observation results show that the length of Julong Karst Caverns is515m,average width is2.4meters, average heights is3.6m. with the addition of branch caves, thetotal length is about2000m. The distribution area is about37000m2. The cave type is galleryfeatures. According to the cave difference of morphological structure, we divided the caveinto two parts, the east and the west. The structure of eastern part is simple and big, the caveenvironment is drying, and the cave landscape is erosion-corrosion type. However, thewestern part is complex, the gallery vary with each other, the cave environment is moist, thecave landscape is complete and various.(2) The cave developed complete and various Karst landscapes. The landscape type canbe divided into erosion-corrosion landscape and chemical deposition landscape. According todissolve morphological characteristics the erosion-corrosion landscape can be divided intopothole type, tubing type and cave-wall protruding type. Deposits landscape can be dividedinto mechanical deposits, chemical deposits, and cave cultural layer deposits landscape. The chemical deposits can be divided into gravitational water (running water, dripping water,splashing water and pool water) deposits landscape, nongravitational water (condensationwater and capillary) deposits landscape, synergetic (dripping-splashing deposits,capillary-condensation water deposits, etc) deposits landscape, superposition landscape.Among all of the chemical deposits landscape, the stone shield is the most, which is rarelyseen in North China.(3) The basic form conditions of the cave are as follows. Firstly, the cave developedmainly in the thick soluble Ordovician Carbonate strata, meanwhile the erosion-corrosiondegree is differ from each other for the heterogeneous Carbonate rocks. So the cave structuralform is varying. Secondly, a large tract Carbonate strata of Ordovician system, which hasabundant fracture-solution crack, is water-bearing layers. With slowly inclined stratumattitude, the Karst water can stay longer in the soluble rock. In addition, multi-period tectonicmovement occurred in research area lead to newly born fracture and early fractures revivemovement. Atmospheric precipitation and surface water follow all kinds of fracture, andinfiltrate into Carbonate water-bearing layers. The soluble rock water storage space and shalewater-resisting layer provide good hydrodynamic condition for cave development. Thirdly,the cave was mostly influenced by numerous fractures. It controls the cave’s distributionpattern, fracture, and extension direction which made Julong Karst caverns became the modeldeveloped by faults tectonic. The eastern part was controlled by NE-NNE faults, and thewestern part was controlled by NW, NWW, nearly-SN faults and the cave morphology ismeander and complicated.(4) Julong Karst Caverns is the coupling effect of neotectonic movement andpaleo-climatic change. Since the Quaternary, lingshan mountain area has undergone severaltectonic uplift movements, formed multistage river terraces, and multilayer Karst Caverns.Through analyzing the cave morphological characteristics, cave height, areal geologicgeomorphic evolution, and paleoclimate evolution, the cave formation stage can becorresponded to Sanhui River third stage terraces formation time. We consider that JulongKarst caverns developed from Pleistocene in Quaternary time.①During Middle phase ofMiddle Pleistocene～early late-Pleistocenc（e0.6～0.12Ma BP）, the coupling between stablegeologic structure and temperate climatic environment, which making the cave space distribution became grid pattern. Karst erosion-corrosion landscapes were complete andvarious.②During the early period of late-Pleistocene（0.12Ma BP～50Ka BP）, the moistclimate and different tectonic uplift movement was relatively strong in this period, leading theincrease of the Karst water and the enhancement of erosion-corrosion function. The branchcave expanded and linked with each other. Karst erosion-corrosion landscapes and depositslandscape were formed. Meanwhile, the cave form was transformed, which was controlled bynumerous secondary faults tectonic.③From late-Pleistocene（50Ka～up to now）, the earthcrust activity was relatively steady, with the change of climatic conditions, mass fault tectonicbecome the channels through which material and energy change from internal to external.Nowadays the cave landscape still vigorously developed.(5) The cave test result demonstrates that mean concentration of CO2is7092ppm, whichis17times higher over the entrance to the cave, the cave average temperature is about18.2℃,which is8～10℃lower than the entrance to the cave. The cave CO2concentration and cavetemperature are regularly changed follow the cave structure and morphology. At theemergence of fault structure, cave CO2concentration reduced while temperature rise, whichreflecting that the internal and external of the cave environment exchanged obviously; at thepart of cave landscape developed vigorously, cave CO2concentration increased, whichindicating degassing effect during the process of landscape deposits; when the cave shapechange from spacious to narrow, as the cave air flow slow and the tourist breath, making thecave CO2concentration stay high.CO2is one of essential factor in cave environmental system, it influence the developmentprocess of landscape deposits. High CO2concentration not only can slow down landscapedevelop process, but also can increase landscape weathering. Long time high CO2concentration can make tourist uncomfortable. High cave temperature can make the caveenvironment turn dry, which making the landscape surface become season crack or evenfracture. The temperature range also can produce condensed water; with the CO2soluble inthe water, the carbonic acid would corrode the landscape.(6) Nowadays the cave develop numerous fault fracture, the rock is breaking, the caveCO2concentration is relatively high, and many cave landscape were damaged seriously. Thecave structure and landscape stability were influenced tremendously. So we should put forward some proposals during the development and conservation of tourism resources:①The cave stability studies must be emphasized and protected the Karst Caverns feasibly;②I n order to make reasonable cave protection scheme, we should monitor the caveatmosphere and evaluate the cave environmental bearing capacity comprehensively andscientifically;③Lighting should be used reasonably to protect cave atmosphere stay original;④We should write scientific guide words to strengthen popularization of science educationand the aware of cave protection;⑤We should enhance the management of scenic region toprotect the Karst tourism resources not suffer destroy from human factor. In a word, weshould use cave tourism resource reasonably within the cave environment can endure. On thepremise of effective cave protection measures, we should develop the tourist resourcesreasonably to make a great effort to build a win-win situation between cave environment andtravel benefit. |
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