URBAN HYDROGEOLOGY IN KARST REGIONS OF CHINA
Yuan Daoxian
Karst Dynamics Laboratory, MLR,Guilin
China University of Geosciences,Wuhan
Contents
* Introduction:Urbanization in China* Functions of Cities in Karsts of China* Urban Hydrogeological & Environmental
Problems* Concluding Remarks
I, INTRODUCTION: URBANIZATION IN CHINA
*1980s: medium size cities: from 180 to 400
*2000: 666, 32 having population more than a million
*Urbanization as a strategic measure : for economic development;
to reduce the differences between developed and poor regions
II, FUNCTIONS OF CITIES IN THE KARST OF CHINA
Karst in China(including buried and covered karst): 3,463,000 km2 , i.e, 1/3 of its territory
Exposed karst: 907,000 km2
Fig.1, Exposed karst in China
Provincial Capitals: Jinan,Shandong province Taiyuan, Shanxi province Kunming, Yunnan province Coal Industrial Cities: Jiaozuo, Henan province Zibo,Shandong province
Fig2, Big Karst Springs in North China
Industrial centers Zunyi, Guizhou province Liuzhou, Guangxi province Agriculture Most of the medium and small size cities ar
e based on local agriculture,but some of them enjoy special products, such as:
Sugar cane: Guigang,Guangxi Tobacco : Menzi,Yunnan province
Fig.3, Exposed Karst in Southwest China
Fig.4, Menzi Basin Chile pepper: Qiubei,Yunnan province
Fig.5, green house nursery of chile pepper Grape & Wine: Mile,Yunnan
Fig.6,Grape yard in Mile county,Yunnan Herb Medicines:Wenshan,Yunnan
Fig.7, Nursery for Panax pseudo-ginseng var. notoginseng
Mineral Deposits Cassiterite: Gejiu,Yunnan Dachang,Guangxi Lead-Zinc: Siding,Guangxi
Fig.8, Surface collapses around Siding City, induced by dewatering in the underlying lead-zinc mining tunnels
Tourisms Fig.9,Stone Forest, Lunan,Yunnan Fig.10, Tropical Karst, Guilin, Guangxi Fig.11,Jinci Karst Springs,Taiyuan, Shanxi
Fig.9,Stone Forest, Lunan,Yunnan
Fig.10, Tropical Karst, Guilin, Guangxi
Fig.11,Jinci Karst Springs,Taiyuan,Shanxi ,North China
III, URBAN HYDROGEOLOGICAL &ENVIRONMENTAL PROBLEMS
The exploitation of natural resources (water,land,mineral deposits, coal, and touristic attractions) benefits the urbanization of karst regions. But hydrogeological and environmental problems,even geological hazards may happen when there is an ignorance of scientific management, which need a good understanding on the karst hydrological system.
Coastal Cities Sea water intrusion in coastal regions of Dal
ian city,Liaoning province,NE China Fig.12,Karst geological section across Dalia
n city
1,caves; 2,coastal erosion cavities; 3,coastal erosion columns; 4,through cave; 5,coastal erosion platform;6,coastal springs; 7,submarine karst springs; 8,S, S1, S2, coastal terraces
Fig.12,Karst geological section across Dalian city
Fig.13, A view on the eastern coast of Dalian,Liaoning,NE China
Cities in the Karst Lowland of Eastern China
Over extraction of groundwater brings about drying of karst springs with touristic attraction:e.g,Jinan, Shandong province
Fig.14, Karst hydrogeological cross section of Jinan city
Fig.15,Karst hydrological variation in Jinan city during the past 40 years
Fig.14, Karst hydrogeological cross section of Jinan city
Fig.15,Karst hydrological variation in Jinan city during the past 40 years (Xi Deyin,1988) 1,precipitation; 2,spring flow;3,water table;4,amount of extraction in urban area;5,sum of extractio
n and spring flow
The Baotu Spring and more than 70 other karst springs which used to flow out around downtown Jinan city,with a total discharge of 300,000 to 350,000 m3/day before 1970s.
Stopped flowing when the extraction from the Ordovician karst aquifer underlain the city was more than 270,000 m3/day.
*A karst collapse happened in Tai’an city,January,1979,right below the major railway between Beijing and Shanghai.
Fig.16, karst collapses in Guizhou and Guang
xi
Fig.16, karst collapses in Guizhou and Guangxi
Cities on the plateau karst, middle of China
Shanxi province,North China Permo-Carboniferous coal measures, the m
ost important energy source of China,are overlying the major karst aquifer (Cambrian-Ordovician)
Fig.17,Schematic hydrological profiles showing the general relationship between karst aquifer and coal measures in North China
Fig.17,Schematic hydrological profiles showing the general relationship between karst aquifer and coal measures in North China (Han Xingrui,1994)
The development of coal industry brings about pollution to the underlying karst aquifers, the major source of urban water supply.
Southwest China Karst Plateau
Cenozoic uplift,and development of underground karst drainage systems bring about:--
Fig.18,Hydrological profile of Menzi
Basin, a typical example to show the relationship between land , cities and underground streams
Fig.18,Hydrological profile of Menzi Basin, a typical example to show the relationship between land , cities and underground streams
*WATER SOURCE PROBLEM Land and cities are usually distributed
on the denudation surfaces of different altitude, but underground streams are dozens to hundreds meters below land and cities. How to find enough water to support the city development is always a challenge.
*FLOOD PROBLEMS When underground streams are not able to dr
ain away excess storm water, flood happens on the surface
Fig.19, Hydrogeological section of Gejiu city,
flooded in 1954 Fig.20, Flood in Sanshi polyje, Donglan C
ounty, Guangxi
1.Metamorphic rock; 2.Granite; 3.Karstified limestone; 4.Argillaceous rock
Fig.19, Hydrogeological section of Gejiu city,flooded in 1954
Nanpan River
1000
1100
13001300
1600
GejiuMenZi Caoba
Kaiyuan
HongheRiver
3 42 1
200
Fig.20, Flood in Sanshi polyje,Donglan County,Guangxi
*POLLUTION Fig.21,Shuicheng city,Guizhou,1800m as
l,polluted waste water from coal mining,and steel manufactory draining into underground streams
Fig.21,Shuicheng city, Guizhou, 1800m asl, polluted waste water from coal mining, and steel manufactory draining into underground streams
(Yao Chenghong,2002)
位置 COD BOD
5
Phenol
CN- As Cd Cr6+ Pb NO3-
水钢出口 1.68 1.54 22.4 0.22
0.68
0.9 0.15 1.26
1.26
落水洞 (1983年 )
0.66 0.37 4.1 0.06
0.14
0.24
0.90 0.30
0.12
落水洞 (1990年 )
1.91 0.51 14.1 2.79
0.14
1.14
3771 0.50
0.48
窑上水库 0.2 0.45 0 0 0 0 0.18 0.04
0.1
IV, CONCLUDING REMARKS For sustainable development of water r
esources in urban areas of karst in China,it is necessary:--
1, to get a better understanding on karst
hydrological systems with respects to coastal, lowland and plateau areas of China;
2,to take into account protecting scenic attractions and ground stability while exploiting resources.
Fig.22, The relationship between Boyu
e Cave system,Hunan and the coal measures underlain
1,Middle-Lower Carboniferous limestone; 2,Lower Carboniferous coal measures; 3,Lower Carboniferous Limestone
Fig.22, The relationship between Boyue Cave system and the coal measures underlain
3, to address properly the relationship between landuse planning/management and karst aquifer protection
Fig.23, Landuse along the Baiyandong und
erground stream,Baojing,Hunan
Fig.23, Landuse along the Baiyandong Underground stream,Baojing,Hunan
4,to carry out vulnerability assessment and mapping for karst aquifers
Fig.24,Vulnerability map of karst water in Houzai underground stream,Puding, Guizhou
Fig.24,Vulnerability map of karst water in Houzai underground stream, Puding,Guizhou
Thank you for your attention!