Textiles Technology Project - The Cotton Industry
-How Cotton is produce:
Cotton was designated the official state fiber and fabric of Texas in 1997. Cotton was first grown in Texas by Spanish missionaries. The missions at San Antonio in 1745 reported growing, spinning and weaving several thousand pounds of cotton annually.
After cotton has been harvested, producers who use conventional tillage practices cut down and chop the cotton stalks. The next step is to turn the remaining residue underneath the soil surface. Producers who practice a style of farming called conservation tillage often choose to leave their stalks standing and leave the plant residue on the surface of the soil.
Seeding is done with mechanical planters which cover as many as 10 to 24 rows at a time. The planter opens a small trench or furrow in each row, drops in the right amount of seed, covers them and packs the earth on top of them. The seed is planted at uniform intervals in either small clumps (“hill-dropped”) or singularly (“drilled”). Machines called cultivators are used to uproot weeds and grass, which compete with the cotton plant for soil nutrients, sunlight and water.
About two months after planting, flower buds called squares appear on the cotton plants. In another three weeks, the blossoms open. Their petals change from creamy white to yellow, then pink and finally, dark red. After three days, they wither and fall, leaving green pods which are called cotton bolls.
Inside the boll, which is shaped like a tiny football, moist fibers grow and push out from the newly formed seeds. As the boll ripens, it turns brown. The fibers continue to expand under the warm sun. Finally, they split the boll apart and the fluffy cotton bursts forth. It looks like white cotton candy.
Since hand labor is no longer used in the U.S. to harvest cotton, the crop is harvested by machines, either a picker or a stripper. Cotton picking machines have spindles that pick (twist) the seed cotton from the burrs that are attached to plants’ stems. Doffers then remove the seed cotton from the spindles and knock the seed cotton into the conveying system.
Once in the cotton gin, the seed cotton moves through dryers and through cleaning machines that remove the gin waste such as burs, dirt, stems and leaf material from the cotton. Then it goes to the gin stand where circular saws with small, sharp teeth pluck the fiber from the seed.
From the gin, fiber and seed go different ways. The ginned fiber, now called lint, is pressed together and made into dense bales weighting about 500 pounds. To determine the value of cotton, samples are taken from each bale and classed according to fiber length (staple), strength, micronaire, color and cleanness. Producers usually sell their cotton to a local buyer or merchant who, in turn, sells it to a textile mill either in the United States or a foreign country.
The seed usually is sold by the producer to the gin. The ginner either sells for feed or to an oil mill where the linters (downy fuzz) are removed in an operation very much like ginning. Linters are baled and sold to the paper, batting and plastics industries, while the seed is processed into cottonseed oil, meal and hulls.
-Social and Economic impact of the Cotton industry:
The largest producers of cotton, are China and India, with a production of about 34 million and 24 million bales, respectively; most of this production is consumed by their respective textile industries. The largest exporters of raw cotton are the United States, with sales of $4.9 billion, and Africa, with sales of $2.1 billion. The total international trade is estimated to be $12 billion. Africa's share of the cotton trade has doubled since 1980.Neither area has a significant domestic textile industry, textile manufacturing having moved to developing nations in Eastern and South Asia such as India and China. In Africa, cotton is grown by numerous small holders.
The 25,000 cotton growers in the United States are heavily subsidized at the rate of $2 billion per year. The future of these subsidies is uncertain and has led to anticipatory expansion of cotton brokers' operations in Africa. Dunavant expanded in Africa by buying out local operations. This is only possible in former British colonies and Mozambique; former French colonies continue to maintain tight monopolies, inherited from their former colonialist masters, on cotton purchases at low fixed prices.
-Environmental impact of the Cotton Industry:
Using current mainstream methods of cultivation, it takes almost a third of a pound (140 grams) of fertilizer and pesticides to produce enough cotton for a single t-shirt. That's almost the weight of the t-shirt itself!
Additionally, seven the most common pesticides used on cotton are either suspected or confirmed carcinogens.
As the modern cotton industry has evolved, insects and weeds have become increasingly resistant to pesticides, meaning that more of these highly toxic chemicals need to be used.
In regard to water, at least 925 gallons (around 3,500 litres) are required to produce a single pound of cotton; and 60% of the water used to irrigate cotton is lost to evaporation and poor irrigation practices. The Aral Sea in Russia, which was one of the world's largest freshwater lakes, has practically dried up due to water being diverted for cotton irrigation.
Somewhere in the region of 79 million acres of land is currently utilized for the production of cotton globally. Cotton covers 2.5% of the world's cultivated land yet uses 16% of the world's insecticides, more than any other single major crop.
The environment has paid a huge price for our cotton demand.
OLIVA BARRIO - 2 eso A 14-11-10
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