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Part 1 IGCP 379 in Late 1996
and Early 1997
Yuan Daoxian
(1) Carbon cycle in epigenic karst processes was monitored on representative sites of different karst system type. They distribute in Austria, Australia, Brazil, China, Cuba, Italy, Russia, Slovenia and Vietnam. According to the available monitoring data on the carbon cycle of several karst dynamic systems on Guizhou Plateau, China, the annual removal of carbon from atmosphere by carbonate rock dissolution in a subtropical humid area is estimated to be 4.15´ 105 tons (Li Bin, the Institute of karst Geology). (2) Deep source CO2 from karst areas A geothermal karst spring in Pamukale,Turkey was studied in 1995. Its hydrochemical parameters which reflect the CO2 outgassing from the hot spring remain almost the same as 1990, i.e. high carbonate hardness, low pH at its outlet, but changing rapidly along its surface flow path. Moreover, the PCO2 in the atmosphere above the hot spring water at its outlet was measured to be 5000ppm. Its d 13C is 1.35‰ as reported by the Institute of Karst Geology (Guilin). Based on the available literatures and noble gas - carbon isotopic data, the Chinese Group has distinguished the deep source CO2 emission on its whole territory into three types, i.e. CO2 emission with very few deposition, mostly in its eastern part where siliceous rocks are predominant; CO2 emission along with many calcareous sinter, mostly in southwest China where carbonate rocks are widespread; and CO2 reservoirs where the active faults from which the deep source CO2 emitted are buried under thick overburden. 20 CO2 reservoirs are reported from mainland China, more are on its continental shelves. Moreover, the Chinese Group has started works on Xiajie Geothermal Karst Spring, Zhongdian County, Yunnan Province. Located on the southern extension of Tethysian realm in SW China, it enjoys great amount of calcareous sinter. The PCO2 in water surface air is measured to be 32,000 ppm, the ?13C is -4.6 ‰ PDB, which tells a possible mantle origin. (3) High Resolution paleoenvironment Reconstruction with Karst Records During the symposium in Turkey, A.Issar reported the results of paleoclimatic records in a speleothem taken from Cango Cave, southern Cape Province, S.Africa. The ?18O paleo-temperatures show decrease from about 30,000 BP, reaching a minimum between 19000-17000 BP. Afterwards, up to 13800 BP the temperature increased. But there is a gap in the speleothem growth between 13000 BP and 5000 BP. Following the paleoclimatic reconstruction back to 36000 years BP with a 1.2m high stalagmite from Guilin (photo 1, 2 and 3), efforts have been started to extend the information in South China back to 200,000 years BP. A 2.5m high stalagmite was taken back. Its interior sedimentological features were studied. (4) Methodologies for the above mentioned three foci of the projects had been specified. Two meetings with excursions took place in Antalya, Turkey, and Singapore-Mulu, Malaysia, with 137 participants from 35 countries, and 31 participants from 12 countries respectively. 10 books or papers were published, some of them in Episodes, Geochimica et Cosmochimica Acta. Photo 1. Chinese colleagues are carrying a big stalagmite from Panlong
Cave, 37 km Photo 2. Interior sedimental structure of the stalagmite from Panglong Cave stalagmite Photo 3. Enlargement of the Holocene/last glaciation transitional part in the Panlong
2. Achievements of the project in late 1996 and early 1997 2.1 General scientific achievements Remarkable progress has been achieved in all the three foci of the project. It was reflected in the project’s two symposia and reports from some National Working Groups. 2.1.1 Carbon cycle in epigenic karst processes. (1) More monitoring sites have been offered to investigate carbon cycle in karst. Including those stared in 1995, a network covering quite different ecological conditions of the world were formed as follows: a. Polar and high mountain karst: John Evans Glacier(Ellesmere Is.), Robertson Glacier, Spitzbergen, Tsanfleuron Glacier(Switzerland), Huanglong,China b. Temperate humid or semihumid regions: Akiyoshidai, Siberia, Kungur
Cave, c. Semiarid regions: North China d. Mediterranean regions : Candamo Cave (N.Spain), Nerja Cave(S.Spain),
e. Subtropical and Tropical Regions: Guilin, Maolan, Hue(Vietnam),
Cienaga de Zapata, f. Geothermal karst: Huanglong, Pamukale, southeast France On such bases, a more objective estimation on the carbon sink by karst processes can be expected. Methodologies of field monitoring on carbon cycle in karst were demonstrated in the field excursion in Guilin (Aug.17.1996, photo 4)
(2) Dual CO2 gradient in soil atmosphere. After two years of monitoring in Guilin, China, the CO2 in soil atmosphere covering limestone are found to have both upward and downward gradient. The finding gives evidence on the carbon sink made by karst processes. (3) Preliminary estimation on the global annual carbon uptake from the atmosphere by karst processes. In the project’s symposium in Beijing, two estimations were given. It was 6.08´ 108t/a (Yuan, China) or 2.2´ 108t/a(Yoshimura, Japan) of carbon in the form of CO2 respectivily. Although there is remarkable difference in the two estimations,which is originated from the parameters used(global outcrop area, mean denudation rate, and mean specific gravity of carbonate rocks), it still tells that the effect of karst processes in the greenhouse gas flux is not negligible. Moreover, John Mylroise estimated a sequestered carbon of 1.1´ 107t/a by dissolution of CaCO3 on world coastal carbonate platform area(6´ 105 km2). 2.1.2 Deep source CO2 in karst area. In southeast France, M.Bakalowicz used three criteria(geochemical, geological, and isotopic approach) to identify deep CO2 in karst processes, and finds the PCO2 in Lez Spring, the water source of Montpellier is as high as 10%. Such high PCO2 are responsible for high HCO3- and Ca2+ contents, resulting in a very active solution of carbonate rocks. Some observations about deep CO2 intrusion were made in the aquifer of the high Guadalantin valley, southern Spain(Ceron Garcia, 1995); the decreasing in water heads in the carbonate aquifer, because of overexploitation, produced a sudden emergence of CO2(up to 85% in Pco2), and HCO3- rich water. 2.1.3 High resolution paleoenvironment reconstruction with karst records. During the Project's meeting in China, the Panlong Cave, 37 km south of Guilin, where a 1.22 m long stalagmite was taken to reconstruct environmental change in the past 36000 years with success was visited. Its results was included in the project’s 1996 newsletter. Prestudy works in selecting the Cave as sampling site were explained, which promoted series of discussion. In Northern Norway, the excursion included 14 caves. The karst feature complex of arctic karst were examined and compared with other karst types in the world. The controlling factors of its formation, i.e., high precipitation, remarkable relief , allogenic water, and last glaciation were discussed. 36 out of 74 papers presented in Bergen, Norway discussed the high resolution paleoenvironment reconstruction with speleothems from Africa, America, Australia, China, Czech,England, Japan, Mediterranean region, New Zealand, Norway, Poland, and Saudi Arabia. Progress in this direction are remarkable this year. Such as: In southern Belgium ( Dominique, Yves Quinif) , fifteen stalagmites from caves and one sealed tunnel are composed of annually deposited white-porous and dark-compact laminae. This is demonstrated by comparing the number of laminae with the local history of the site for modern stalagmites and with radioisotopic ages for Late Glacial and Holocene stalagmite.Annual cyclicity in the internal structure of these speleothems is explained by the highly seasonal variations of the water excess, which influences underground water flow. Vertical successions of several laminae represent microsequences that may have recorded climatic variations with a time resolution of 1/2 year . In a Late Glacial stalagmite , successive laminae microsequences from very regular cycles of 11years separated by a thick dark-compact lamina. It is supposed that , as for modern stalagmite , the thick dark-compact lamina corresponds to a period of high water excess. Hence, this 11-year cycle may reflect a climatic cycle. In southern part of South Island, New Zealand ( P. Williams) , seven glacial advances in the last 230 ka were underpined by 26 U- series dating on speleothem from Aurora Cave. In Beijing, China (Tang Ming), a late Holocene rapid climatic change was recorded by stable isotopic data in a speleothem from Shihua Cave. Moreover, luminescent microbanding in the speleothem was examined. In the Bergen meeting, the methodologies to extract high resolution paleoenvironment information from speleothem were discussed into depth, including dating method, climate proxy data and ecology proxy data. 2.1.4 Contribution to Global Change Study The most important results of the Project had made contribution for the Global Change Study. In late October,1995, the project leader presented a paper(Geological Aspects of Modern Cabon Cycle in Mainland China) at the fourth Scientific Advisory Council Meeting of IGBP(SAC-IV) in Beijing. According to the suggestion made by IGCP 379 leader, the scientific goal of the Project was adopted by the SAC-IV resolution as one of its future direction as saying that "the influence of geological processes on biogeochemical cycles, in particular geo-sources of CO2, and its uptake by rock-weathering processes" should be considered in further evolution of the programme. 2.2 Meetings held in this period (1) Symposium " Formation and evolution of karst and data of environmental change (including IGCP379 )" August 8-9, Beijing , in conjunction with the 18-6 session of 30th International Geological Congress, and relevant karst excursions of semiarid karst in Western Hill of Beijing (T206) and subtropical monsoon karst around Guilin (T347). 42 persons from 16 countries took part in the symposium. 30 persons joined the excursions, 31 abstracts were submitted. (2) IGCP379 meeting in Bergen, Norway, August 1-16, including excursion in Northern Norway August 5-16. The meeting was in conjunction with the international symposium "climatic change- the karst records". 72 persons from 22 countries took part in the symposium. 74 papers were presented. 26 persons joined the excursion. (3) Joint meeting with INQUA COMMISSION ON CARBON The commission was established during the 14th INQUA congress held in Berlin(August, 1995). It is intended to foster scientific cooperation for the study of how the carbon cycle changes during glacial and interglacial oscillations and its role in the Earth System. It includes 6 thematic WG : weathering as carbon sink ; karst processes and the carbon cycle(IGCP 379); carbon release from the lithosphere; modelling carbon cycle in the past; carbon in lake; continental shelves carbon(IGCP 396). 52 people from 18 countries participated in the meeting in Mauritania, including members of IGCP 404 "Terrestrial Carbon", IGCP 349 "Desert margin and paleomonson in the past 135,000 years", and IGCP 379. 40 papers were presented at the symposium from Jan. 6 to Jan. 8. The excursion during Jan. 9 through Jan. 12 took place at the coastal area from Nouakchott to Tafarit, 300 km to the north of Nouakchott. Sites with paleoclimatic change proxies, including marine deposit, eolian sediment, karst feature, and archaelogical findings were investigated (see cover photos and photo 5). 2.3 List of most important publications 1. IGCP379 Newsletter 1996. 88 pages. The Institute of Karst Geology, Guilin, China 2. Papers presented in Bergen were published in: S.E. Lauritzen (ed.) (1996), climate change, the karst records, Karst Waters Institute Special Publication 2, 196 pages, KWI, West Virginia 3. 23 abstracts of papers presented in Beijing were published in the 30th IGC. Abstract book vol.3, pp432-438. Selected full text will be published in vol.24 of 30th IGC proceedings, VSP. 4. 40 abstracts of papers presented at the Nauakchott meeting were published in abstract book (eds. H et L. Faure) 5. M.M. Sweeting, 1995, Karst in China, its geomorphology and environment, 260 pages, Springer 6. P. Williams, A 230 Ka record of glacial and interglacial events from Aurora Cave, Fiordland, New Zealand, New Zealand Journal of Geology and Geophysics, 1996, vol.39:225-241 7. Y.Y.Shopov et al, Speleothems as natural climatic stations with annual to daily resolution, in book " Climatic Change-the Karst Record" . 1996. Ed. by S.E.Lauritzen, KWI, Bergen, p150-151 8. Yoshimura, K et al, Tufa in limestone areas in Southwest Japan, 1996 , in Bulletin of Speleological Society of Japan, 20, 19-26 9. Juraj Cincura et al, Paleoalpine Karstification- The longest Paleokarst Period in the western Carpathians ( Slovakia) . 1995, Geologica Carpathica, 46, 6, 343-347, Bratislava 10. Dominique Genty and Yves Quinif, annually laminated sequences in the internal structure of some Belgian stalagmites- importance for paleoclimatology, Journal of Sedimentary research, Vol.66, No.1, p275-288,1996. 11. Xu Shengyou and He Shiyi, The CO2 regime of soil profile and its drive to dissolution of carbonate rock, Carsologica Sinica, Vol,15, No. 1-2, p50-57, 1996 12. Li Bin and Yuan Daoxian, Relationship between carbon cycle in karst areas and CO2 source- sink of atmosphere- case of Guizhou Karst, Carsologica Sinica,Vol.15, NO.1-2, p41-49,1996 13. Ivo Karmann, the modern dynamics of the upper Ribeira Karst, Southeastern Sao Paulo State, Brazil, paper presented at 30th IGC, August, 1996, Beijing 14. Kazuhisa Yoshimura, The geochemical cycle of CO2 in a carbonate rock area, Akiyoshi-dai Plateau (Yamaguchi Prefecture, Western Japan), accepted to be published in 30th IGC proceedings, Vol. 24, pp114-126 VSP, Netherlands,1997. 15. Michel Bakalowicz, deep CO2 contribution to karst processes from examples of French Mediterranean Karsts, paper presented at 30th IGC, August, 1996, Beijing 16. Martin Knez, Karst cave development from the bedding-plane point of view, Skocjanske Jame Caves, Slovenia, accepted to be published in 30th IGC proceedings, Vol.24, pp86-105, VSP, Netherlands,1997. 2.4 Cooperation with other IGCP projects or the IUGS (1) IGCP 349,IGCP 387(296), IGCP 341, IGCP 404. According to the advices from IGCP Board, we have contacted IGCP 349 "desert margins and paleomonsoons of the old world: 135,000 years to the present"(1993-1997); IGCP 404 "Terrestrial carbon in the past 125ka" (1996-1999); IGCP387(successor of 296) "Quaternary in the Asia/Pacific region" (1989-1993); IGCP 341 "southern Hemisphere paleo- and neoclimate". We were invited to attend the joint meeting of 349 and 404, held on Jan.5-12,1997 in Noukchott, Mauritania, with a scientific programme of "desert margin change in Africa since 135ka: implication for water,carbon and mankind". (2) KARST COMMISSION OF IAH (Prof. Heinz Hotzl, Germany) The Project is initiated and has got continuous support from this commission. The implementation of this Project has been in many cases in coincidence with its activities. In June 10-13, 1996, the project members participated in the commission’s 24th session in Katowice, Ustron, Poland, in conjunction with the international symposium on karst-fractured aquifers-vulnerability and sustainability sponsored by the University of Silesia. Proceedings including 29 papers were published by Silesia University. Sites with paleoclimate karst records and modern karst environmental problems were visited in the excursion (photo 6 to photo 9). The Karst Commission will have its next annual meeting (1997) in Switzerland, in conjunction with the 12nd Congress of the International Union of Speleology (August 10-17).
Photo 6. limestone peaks asserted to be relic of Tertiary mogotes at
Ryczow, (3) GLOBAL COMPARISON OF EPIKARST( A.Klimchouk,Karst Commission of IGU, and UIS WG on karst hydrogeology ) 25 participants from 9 countries. Objectives : to compare characteristics of epikarst on global basis; to reveal factors controlling variability of structure, morphology, and hydrologic function of epikarst; to assess the role of epikarst in karst hydrology and morphogenesis; to prepare a monograph.
3. Activities of the project in 1997 3.1 General goals The progress in 1997 for all the three foci of the Project will be planned as follows: (1) The estimations of global CO2 drawdown from atmosphere by karst processes made in 1996 will be checked by carefully reviewing all the parameters used on the bases of the new data collected from monitoring sites at different ecological systems of the world. The main parameters which should be checked included the global area of carbonate rock outcrop, the representative denudation rate in different regions and the specific gravity of carbonate rock; (2) Deep resource CO2 emission in karst areas will be investigated on more sites, especially in the Tethysian realms. Its origin and relationship with geological structures will be studied, and amount of CO2 emission be estimated; (3) Higher resolution karst records will be more explored to reconstruct paleoenvironment change, especially in those regions with less other paleoenvironment proxies, such as south China karst area, South Africa and southern Australia. Some bilateral cooperations under this direction will probably be put into implementation later this year, such as Sino-Australian, Sino-French and Sino-USA. 3.2 Specific meetings and field trips (1) IGCP 379 meeting in Lipu, China, April 26-30, 1997. Colleagues from Australia, France, Japan, Russia, USA, Vietnam and China will attend the meeting to exchange results and discuss future works of the project. Experimental sites related to this project will be visited. (2) IGCP 379 meeting in La Chaux-de- Fonds( Neuchatel) , Switzerland, August 10-17,1997. In conjunction with the 12nd International Congress of Speleology, and Symposium on hydrology of limestone. Field excursions will be arranged to examine karst in French and Switzerland Jura, French Alps, Italian Alps and Slovenia karst.
4. Other relevant informations (1) An email list including about 90 participants of the Project from 25 countries and regions has been put into use, and facilitate fast communication. A Home Page for IGCP 379 is also put into operation (http://www.gxnu.edu.cn). Participants are very much welcome to visit. (2) We have also contacted and exchanged with other international projects and organizations with similar direction: I. CARBON FLUXES IN HYDROLOGIC AND GEOLOGIC PROCESS (A national research program of USA, Sundquist, E.T) The objectives of the Project are : To evaluate local to global carbon fluxes associated with hydrologic and geologic processes; to determine the geochemical mass balance for carbon in selected hydrologic/geologic systems; to determine the processes most important in controlling carbon fluxes; to investigate the possibility of past variations in world’s(natural) CO2 balance, and to apply this information to the prediction of future global CO2 fluxes; and to understand the role of fluxes of carbon compounds in selected local ground water and/or surface water contamination problems. II. CDIAC (CARBON DIOXIDE INFORMATION ANALYSIS CENTER, WORLD CENTER-A FOR ATMOSPHERE TRACE GASES) CDIAC is sponsored by U.S.Department of Energy’s Global Change Research Program. Its publication (CDIAC Communications) twice a year include latest development of research on CO2 and other trace gases in atmosphere. III. PAGES/IGBP To verify GCM (General Circulation Model), effort will be made in the next few years to get high resolution paleoclimatic change records along PEP-I, PEP-II and PEP-III Transect for the past 200,000 years and 2,000 years. IV. RAPID SEDIMENTATION AND HIGH RESOLUTION STRATIGRAPHY: PROCESSES AND APPLICATIONS, A STRATEGIC UNIVERSITY PROGRAMME (SUP) 1996-1999 Proposed by the Department of Geology, University of Bergen, Norway, it includes 4 tasks: rapid changes,sediment flux and environmental variability on the continental margin; fjord sediments as archives for ultra-high resolution stratigraphy; glacial fluctuation and high resolution continental stratigraphy; Ultra-high precision stratigraphy from speleothem (Stein-Erik Lauritzen). The last one is quite related to one of the aims in IGCP379.
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