Agriculture problems - Cotton
The impact of cotton on freshwater resources and ecosystems
Due to technical innovations, however, this has now changed and today cotton takes up 48% of textile production, while 45% is taken up by synthetics, with the rest accounted for by other fibres.
Cotton production occurs between 36° South latitude and 46° North latitude and is located in tropical and subtropical regions (Reller, 1997). The broad belt of irrigated cotton lays in Mediterranean and desert climate. It stretches from Spain to central Asia and contains those regions with similar climates in the west of North and South America and Australia (Gillham, 1995).
Many cotton regions are located in important river catchments. The Indus River valley in Pakistan, for example, incorporates one of the greatest irrigation systems in the world.
Table 1 lists the major river catchments which can be affected by cotton production.
About 73% of cotton is produced in irrigated fields and only 27% under rain-fed conditions (freshwater is provided mainly by rain). The average yield of cotton is 854kg per ha for irrigated cotton and 391kg per ha for rain-fed cotton.
In 1998 the world production of cotton amounted to 18.3 Mio tonnes of cotton lint and today, 33 Mio hectares of land are given over to cotton plantations. Whereas the area of cotton plantation's have remained more or less constant since 1930, cotton production has tripled in the last 70 years.
Table 1: River catchments in cotton producing areas
|China||Yellow River Valley (30.6%)
Yangtse River (61.3%)
|Pakistan||Indus Valley (largest irrigation system world-wide; continues to India)|
|Turkey||Menderez, Gediz GAP Scheme A (Euphrat and Tigris)|
The cotton production is unequally distributed over the world. Over 71% of the total cotton harvest occurs north of latitude 30° N where the major cotton producing countries are located (Gillham, 1995). Over 70 countries are involved in cotton production but the 6 major ones (China, United States, India, Pakistan, Uzbekistan and Turkey) account for over 75% of total world production (ICAC, 1995).
Cotton plays a major role in the economy of many cotton producing countries. Cotton production, however, is only one element in the multisectoral processing of cotton which has a high economical relevance.
For example, the cotton sub-sector in Mali represents 50% of the exports. In Pakistan over two thirds of the export earnings are derived by cotton and textiles and in Uzbekistan the sale of cotton lint accounts for 75% of the export earnings. In many developing countries in Asia, Africa and Latin America cotton is the cash crop of smallholders.