Ecology : The ecological disaster of the Aral Sea
In 1960, the Aral sea was one of the world’s biggest inland seas with a surface area of about 66’900 square kilometers. The Aral sea and its surrounding region formed an ecosystem with an extraordinary biodiversity. Today, the surface area of the sea has shrunk to just 24’900 square kilometers, the ecosystem has suffered tremendous damage, and the indigenous population suffer from sickness and hunger. What are the reasons for this disaster ?
The principal reason for the destruction of the Aral sea region is the replacement of traditional hemp cultivation by that of huge areas of cotton cultivation.
Geography and population The Aral sea is situated in the south of Kazakhstan. The two principal rivers which feed the Aral, the Amou-Daria and the Syr-Daria, have their origins in the Pamir (7’495 m.) chain of mountains. They both contribute about 67 cubic kilometers of water per year. The climate of the region is dry - there is very little rainfall, about 20cms. per year compared to 60-240 cms. per year in Switzerland. The deserts and steppes of the region are sparsely populated, with most of the population concentrated around the river banks and deltas. They live off agriculture for the most part, which in turn depends on them being able to irrigate the land. Some farm animals, such as goats and Karakuls, are also raised.
Inefficient irrigation techniques The ecology of the region does not lend itself to intensive agricultural practices, even less so when it comes to cotton cultivation. In spite of this, highly inefficient agricultural practices which require enormous amounts of water have been the norm in the Aral sea region since the 19th. century. Since 1960, under Soviet rule, the area of cotton production quadrupled. Add to this the usage of vast amounts of water for irrigation, artificial fertilizer, pesticides and herbicides. The huge system of canal irrigation, where by itself the Karakoum canal consumes 17 cubic kilometers of fresh water per year, is in such a state of disrepair that most of the water is lost.
Consequences for the ecosystem The large amounts of water used up by crop irrigation have caused an increasingly dramatic sediment and silt buildup in the deltas of the main feeder rivers. Since 1976, for example, the Syr-Daria river delta has retreated inland so that today the river finishes its course 160 Km from the banks of the Aral. Today the Amou-Daria river provides only 10% of its former volume of water. The disaster is compounded by the imbalance between rainfall in the region (20 cms. per year) and the evaporation rate which presently is around 104 cms per year. Another negative consequence is the salt buildup in the soil which leads to poorer and poorer crop yields as nutrients become locked and unavailable to plants. As of today more than 40’000 square kilometers of the Aral sea have disappeared. This huge reduction in water volume has caused the region’s climate to become continental, with shorter growing periods and soil erosion driven by wind. A good number of ecologists estimate that the Aral sea region’s ecosystem is effectively destroyed, never to recover.
Consequences for the population The quality and profitability of agricultural produce in the region is poor due to, as previously mentioned, salt buildup in the soil and the pollution caused by the excessive use of pesticides and herbicides. Rice cultivation in the deltas is no longer possible since rice plants are intolerant to excessive soil salt. Basic foodstuffs are contaminated and drinking water has been polluted resulting in serious consequences for the health of animal and man. The region’s population is increasingly affected by all these polluants. 63% of adults and 60% of children are afflicted by illness. Cases of respiratory sickness, diarrhea, tuberculosis, anemia, cancer, and birth defects have increased by 159% between 1989 and 1997. Life expectancy has dropped to around 40 years and infant mortality is in the region of 15% ! Yes, around one in seven infants die ! That is incredible. Since the collapse of the former Soviet Union, public health services in the Aral sea region have also collapsed to the point of being non-existant.
Perspectives for Aid and decontamination Scientists estimate that it would be impossible to revive the region’s pristine ecosystem of 1960. This would take centuries to achieve. The current situation requires emergency support projects such as stemming the silting up of river deltas, stabilizing the ecosystem and helping the population. Since 1997, Médicins sans frontières (doctors without borders) have been present in the region as a public health support, notably in the fight against tuberculosis. Unfortunately they can only do so much with their limited budget. Several associations like the Deutsche Forschungsgemeinschaft (DFG), the Centre National de la recherche Scientifique (CNRS) and the International Association for the promotion of cooperation with scientists from the new independent states of the former Soviet Union (INTAS) have jointly launched an appeal for urgent aid and decontamination projects. In times past, before the greed and ignorance of politicians resulted in these huge expanses of cotton cultivation, the region’s population cultivated hemp, a fibrous plant with no need of pesticides and herbicides and which can live off the natural fertilizers found in soil. We really hope that the aid projects for the region will also result in the reintroduction of the hemp plant, since one of its really positive impacts, among many others, would be to assist in the detoxification of the soil. Hemp is able to assist in soil detoxification because it has the ability to enrich soil and at the same time extract toxins without harming the plant itself (minimum 1% per vegetative period).
- La mer d’aral en 1972 et en 2004