Lake Toba - Indonesia

Lake Toba is a large tekto-volcanic natural lake that occupies the caldera of a supervulkan. This lake has a length of about 100 kilometers, a width of about 30 kilometers, and a depth of up to 505 meters (16666 feet), located in North Sumatra Province, Indonesia. Lake Toba is the largest lake in Indonesia and Southeast Asia. In the middle of this lake there is a volcanic island called Samosir Island.

HISTORY

It is estimated that Lake Toba was formed during an explosion of about 73,000-75,000 years ago and is the most recent eruption of Supervolcano (volcano). Bill Rose and Craig Chesner of Michigan Technological University estimated that the total amount of material at the eruption was about 2,800 km3-about 2,000 km3 of Ignimbrit that flowed over the ground, and about 800 km3 that fell as mainly westward to ash. The pyroclastic flow from the eruption destroys an area of 20,000 km2, with ash deposits as thick as 600 m with the main crater.

This incident caused mass death and extinction in some species of living things. According to some DNA evidence, this eruption also shrinks the human population to about 60% of the total human population of the earth at that time, which is about 60 million people. The eruption also contributed to the occurrence of an ice age, although experts are still debating it. After the eruption, a caldera was formed which then filled with water and became what is now known as Lake Toba. Upward pressure by the magma that has not yet come out causes the emergence of Samosir Island.

An international multidisciplinary research team, led by Dr. Michael Petraglia, revealed at a press conference in Oxford, United States that a new archeological site has been discovered that is quite spectacular by geologists in the south and north of India. On the site it was revealed how people survived, before and after the Toba volcano (supervolcano) eruption 74,000 years ago, and evidence of life under the ashes of Mount Toba. Though the source of the eruption is 3,000 miles away, from the distribution of the ashes.

For seven years, experts from the Oxford university have been researching ecosystem projects in India, to look for evidence of life and the lifestyle they left behind in barren fields. This area of ​​thousands of hectares is just a savanna (grassland). While animal bones scattered. The team concluded, this large area was covered with dust from the eruption of ancient volcanoes.

The spread of volcanic dust is immense, found almost all over the world. Derived from an ancient supervolcano eruption, which is Mount Toba. Allegations lead to Mount Toba, because found evidence of the same form of molecular volcanic ash at 2100 dots. Since the caldera crater is now a lake Toba in Indonesia, up to 3000 miles, from the source of the eruption. Even quite surprising, it turns out that the spread of dust to be recorded up to the North Pole. This reminds the experts, how terrible the super eruption of Toba volcano at that time.

 

Environmental damage 

In May 2012, Samosir regency issued a decree (SK) of the Regent of Samosir no. 89 dated May 1, 2012 on the granting of Horticulture and Husbandry Plantation Business License covering an area of ​​800 hectares in Tele Forest, Partungkot Nagijang Village and Hariara Pintu, Harian District, Samosir Regency, North Sumatra to PT Gorga Duma Sari (GDS) owned by a member of DPRD Samosir District, Jonni Sitohang. Then continued with Wood Utilization Permit (IPK) granted by the Head of the Provincial Office of North Sumatra through Decree of Head of Department of Forestry and Plantation of Samosir Regency Number 005 Year 2013. The Chairman of the Care Forum Forum Samosir Nauli (Pesona), Rohani Manalu stated that this permission makes PT GDS logging natural timber in the forest without having an AMDAL. Rohani also stated that another consequence is the occurrence of landslides and floods that cause casualties. Due to Tele logging, the eroded sludge above the logged-over soil has caused siltation of rivers around Lake Toba. The program of planting a million trees that is driven by the government of  North Sumatra Province was said to be ineffective because many trees died because they were not treated. This led to three environmental activists of North Sumatera, Marandus Sirait, Hasoloan Manik (Kalpataru), and Wilmar Eliaser Simandjorang (Satya Lencana Karya Satya, Toba Award, Wana Lestari) returned all the awards presented by North Sumatra Provincial Government, Ministry of Forestry, and The State Palace. Environment Minister Balthasar Kambuaya has sent two letters of recommendation for the Regent of Samosir Mangindar Simbolon as the business licensee and responsible for administrative sanctions in the form of closing business activities. After the first letter was ignored, the Regent of Samosir answered the second letter by stating that the company did not violate it so it was not worth closing. Because the Bupati does not implement the recommendations, the Ministry of Environment also imposes a Second Line Enforcement and temporarily closes PT GDS activities. After the Ministry of Environment dropped directly to the location based on findings that the decision was ignored, then Pemkab wrote PT GDS to comply with the decision letter. PT GDS suspended all operational activities and withdrew heavy equipment in the area under the recognition of GDS Director Jonni Sitohang.

SOURCE : wikipedia