Impacts of Urbanization and Industrialization on Agriculture in Zhujiang Delta (ZD)

1. Impacts of Urbanization and Industrialization on Agriculture in Zhujiang Delta (ZD) Dr. Ng Sai Leung (伍世良) Department of Geography and Resource Management The Chinese University of Hong Kong September 2001

2. Outline • Introduction • Agriculture in ZD • Urbanization and Industrialization Impacts on ZD’s Agriculture

3. Zhujiang • Zhujiang (珠江, in Chinese, means Pearl River) is named because of the Pearl Rock (走珠石,a red Cretaceous sandstone exposure located at Guangzhou). • Zhujiang is not a single river, but a river network. • 3 major rivers and 8 outlets (三分河道,八分河口) • ZD is a compound delta (複合三角洲)

4. Zhujiang and Agriculture • Zhujiang Delta has a total area of 453,000 km2. 3/4 of land is flatland with fertile soil and sufficient supply of fresh water. • Traditionally, it is the most important and one of the ten most important grain production areas in in Guangdong province and China. • Zhujiang Delta has experienced remarkable economic growth since 1978.

5. Significance of Agriculture in ZD • Whether or Zhujiang Delta can sustainably develop, agriculture plays a vital role. • Agriculture is of importance to 20 million people in the region not only in the sense of providing foods and grains but also in offering job opportunities. • Agriculture is important in terms of environment and ecology.

6. Favourable factors to agriculture • Climate • Soil • Arable land • Natural ecology • River network • Location

7. Climate • Subtropical monsoon maritime climate (plently precipitation and >10oC the accumulative annual temperature is greater than 7500oC). • Long cropping season and multiple cropping (3 seasons for rice and the 4th for bean, 三造稻四收荳). • Guangdong and Hainan are two only regions in China, which can produces tropical crops.

8. Soil • The deposits of the delta are generally 20-40m in thickness. • Sediments are rich in organic substances (about 0.6 million tones per year). • Long soil formation period enables to accumulate nutrients.

9. Arable land • Zhujiang has a discharges approx. 7 times of Yellow River. Sediment content is 0.13-0.34kg/m3, total loading is 85 mill ton. • The coast extends 100 m outward every year, translating into a total area of 15 thousand hectares. • More than 0.3 million hectares have been recreated from reclamation since 1949. • Because of large river discharge, salt content in soil can be removed quickly and easily.

10. Natural Ecology • Terrestrial habitats because of topography • Estuary habitats because of sedimentation

11. River networks • High accessibility of Zhujiang River provides fast and convenient transportation for the region. There are many advantages: • Cut down the cost of transportation • Reduce damages of grain and crops • Maintain the freshness of produces

12. Location • Close linkage with Hong Kong and Macau in terms of culture, economics and technology • A large outlet for agricultural produces.

13. Characteristics of agriculture in ZD • Fragmented • Intensive • Integrated • Special techniques: tidal irrigation, ecological dyke ponds, etc.

14. Landuse in Guangdong

15. Paddy field (水田) • Mainly for cultivating paddy rice (about 80%) and sugar cane (about 10%). • Sustain three crops a year. Cultivation sequence is rice-rice-vegetables (or rest) or rice-sugar cane rotation. • Series of paddy field align along the coast-inland transact: • Xiantian (saline field, 鹹田), shatian (sand field, 沙田), weitian (reclaimed field, 圍田), langtian (field on the hill, 塱田), tungtian (field on the basin, 垌田) and hangtian (stony field, 坑田). • Only two crops (paddy rice) are allowed in low productive fields, e.g., saline field.

16. Dry field (旱田) • Distribute over plateaus and undulating with an elevation of 1-40m, slope is relatively steep (5-15o). • Parent materials are usually granite or reddish siltstone. • Difficulty in irrigation and soil erosion are main concerns.

17. Orchard (菜地) • Including land for vegetables and fruits. They are not large in area, usually <100 acres They are usually scattered at the fringes of cities and market towns. • “Four fruits of Lingnan 嶺南四果” are tangerine, banana, pineapple and lychee.

18. Woodland • Original subtropical monsoon evergreen broad-leaved forest has almost disappeared. • Secondary forest (characterized by pines and shrubs) is the dominant type now. • Small pieces of Fung Shui woodland can be found in remote villages. • Wind break can also found in coastal areas while mangrove found in mudflats.

19. Grassland • Grassland is a relatively primitive ecological habitat. • It is an “artifact” of human disturbance. • Natural grasslands are found at hilly areas and low hills. • Artificial grasslands developed in recent years, mainly for cow and fish feeds are scattered over the dyke pond area.

20. Dyke pond (基塘) • The excavated soils are used to construct the dykes. • Dikes are usually 0.5-4m in height, ponds are 30m in width and normally 100m in length. • According to area of dyke, proportion of dyke to pond can be classified into: 3:7, 4:6 (commonest) and 7:3. • Dyke ponds which are classified based on the dominant crop grown. There are 4: mulberry, sugar cane, fruit, and miscellaneous.

21. Tidal flat • Tidal flat is shallow beach at coastal area, it mainly located at Humen, Jiaomen, Hengmen, Modaomen. • According to the sediment size, it can be classified into sand beach, muddy beach, grass beach and mangrove area. Sand beach can be found at the river month while other three can be found adjacently.

22. Impacts of Economic on Agriculture • Loss of arable land • Pollution • Structural transformation

23. Loss of arable land

24. Environmental problems • Over-emphasis on economic growth, failure in central policy planning and ignorance of environment • 3 wastes: water, air and solid pollution • Point source vs non-point source pollution • Ecological degradation: habitat loss, pollution and human disturbance • China’s accession to WTO

25. Structural transformation • Manpower • Market economy • Decline in grain production • Rise of economic crops. • Three “highs”(三高農業)

26. Shrinkage of grain production

27. Development of Zhujiang Delta ~ End ~