Tonlé Sap

The largest lake in Southeast Asia

The Tonle Sap ( Khmer for Great Lake ) in Cambodia is the largest lake in Southeast Asia and one of the richest fishing inland waters of the earth.

• 3.1 overfishing
• 3.2 pollution
• 3.3 dams

Geography

From the north of the lake is fed by several tributaries in the south exits, named after the lake Tonle Sap River, which flows into the Mekong in Phnom Penh. Every year in June there is observed a globally unique natural phenomenon. The Mekong leads at this time due to the monsoon rains and by the melting water from the Himalayas up to four times more water than during the dry months. Since Cambodia is a mostly very flat and level land, urging the waters of the Mekong into the Tonle Sap River, and this changes the direction of flow. The water masses get back into the basin of the Tonle Sap and fill the lake during the dry season an area of ​​2,600 - has 3000 km ², it is set approximately 10,400 km ² (including surrounding river landscapes: up to 25,000 km ² ) increases and up to five times as deep ( 2-3 m to 14 m). The peak of the flooding is reached in September. At this point is covered by water just under a third of the agricultural cultivated area of Cambodia.

It was only in November, when the Mekong again leads less water, the river changes direction again, and the lake water flows slowly. This event has given rise to the so-called hard water ( khmer: Bon Om Touk ), which simultaneously represents the beginning of the fishing season.

Economic Importance

For centuries, fishing and rice farming are the main economic activities of the rural population of Cambodia. Rice and fish are the main components of Khmer cuisine. And both are dominated by the annual rhythm of the Tonle Sap.

Traffic

The lake also serves as a transportation route. Ferries and hydrofoils link the city in the northeast of the Tonle Sap Siem Reap to the capital Phnom Penh in the south and over the opening into the lake in the northwest flow Sangker with Battambang, the second largest city in the country. About the Mekong River, it is also possible to reach Vietnam and Laos on the waterway. The Tonle Sap River and the Tonle Sap Lake are the main roads in this part of Cambodia. Due to the bad road, a large part of the goods and people is transported by water.

Rice

The annual flooding by rivers and lakes guarantee the watering and fertilizing the rice fields, which must be irrigated during the dry months over canal systems.

Fish

Mian dtoek, mian trey - ' Where there is water, fish are ' ( proverb Khmer ).

For the fishing season begins in November, when the amount of water of the lake decreases slowly and the abundance of fish according to the months of the flood has reached its peak. It is estimated that in Cambodia as a whole ( including coastal fishing ) are caught 225,000 tonnes of fish annually, most of them in the inland waters and of this half of the Tonle Sap. Fish alone provides at least three quarters of the consumed in Cambodia protein.

Ecology and hazard

The Tonle Sap forms, together with the rivers the Tonle Sap, Mekong and Bassac a unique ecosystem that not only species richness ( 300 species of fish, birds and a m. ) In water and allowed in the surrounding area but also crucial for the development of living in the area people and their culture was.

The historical kingdoms of the Khmer, with its center just a few kilometers north of the lake nearby Angkor, be without the water and the associated wealth of food probably not have been possible.

Today, the structure of seasonally changing spawning periods, fishing, agricultural use and fertilization of the surrounding area in danger.

Overfishing

The lake is still one of the best fishing of the earth, but the beginning of an industrial fishing is already showing first episodes and fishermen report a drop in income. Nylon nets, which are transversely excited, contrary to earlier traditions through rivers, let fishermen downriver hardly the way to catch fish themselves. The methods change. Instead of throwing nets and made ​​of wood, reeds and bamboo -made traps are also sometimes grenades, batteries, or poison used.

The decline in fishing yields and the increased demand for meat for the fantastic nearby crocodile farms have meant that in the past two decades, increasingly, water snakes, mainly copies of the Striped Water Snake ( Enhydris Enhydris ), were fished out of the lake. Currently, there are about seven million units per year. A result, the population of these animals are extremely vulnerable, since there is no closed season for the snakes in the breeding season, from November to December (see Chapter film).

Pollution

Another problem is the contamination of the water. The floods bring silt annually and fresh with it, fertilizes the fields in a natural way. Today, this silt is increasingly contaminated - especially with the waste water from the nearby upstream on the Mekong industrial plants in Thailand and the People's Republic of China.

Dams

As in many other developing and emerging countries already with controversial consequences (see Arundhati Roy's essays on the dam project Sardar Sarovar in India) done for people and the environment should also accelerate in Cambodia dams economic development. Plans are currently (as of 1999), eight dams on the tributaries of the lake, three on tributaries of the Mekong and five more on smaller rivers. In addition, already threaten existing and other planned dams in neighboring countries to disrupt the seasonal rhythm of the internal water system. The Mekong is to be used in Laos for 56 dams in Vietnam for 36, Thailand is planning two more to the 39 already existing and to an irrigation project that would deprive the Mekong every year 12,000 million cubic meters of water, and in the People's Republic of China, seek to existing six more dams are being built.

Film

• 360 ° - Geo Reportage: In snake catcher in Cambodia. Documentation, Germany, France, 52 min, 2007, a film by Thérèse Engels, Production ZDF, arte, Original Air Date: December 29, 2007 Summary of arte
• Cambodia 's declining fish stocks - Report on Al Jazeera English on August 12, 2010 (video, English)