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!