Semeru


Semeru, or Mount Semeru, is an active volcano in East Java, Indonesia. It is located in the subduction zone, where the Indo-Australia plate subducts under the Eurasia plate. It is the highest mountain on the island of Java. This stratovolcano is also known as Mahameru, meaning 'The Great Mountain'''.
The name derived from the Hindu cosmology's mountain of Meru or Sumeru, the abode of gods.
Mount Semeru is one of the most popular hiking destinations in Indonesia.

Geology

Semeru rises steeply above the coastal plains of eastern Java. Maars containing crater lakes have formed along a line through the summit of the volcano. It was formed south of the overlapping Ajek-ajek and Jambagan calderas. Semeru lies at the south end of the Tengger Volcanic Complex.

Eruptive history

Semeru's eruptive history is extensive. Since 1818, at least 55 eruptions have been recorded consisting of both lava flows and pyroclastic flows. All historical eruptions have had a Volcanic Explosivity Index of 2 or 3. Semeru has been in a state of near-constant eruption from 1967 to the present. At times, small eruptions happen every 20 minutes or so.
Semeru is regularly climbed by tourists, usually starting from the village of Ranu Pane to the north, but though non-technical it can be dangerous. Soe Hok Gie, an Indonesian political activist of the 1960s, died in 1969 from inhaling poisonous gases while hiking on Mount Semeru.

Mythology

Semeru is named from Sumeru, the central world-mountain in Hinduism. As stated in legend, it was transplanted from India; the tale is recorded in the 15th-century East Javanese work Tantu Pagelaran. It was originally placed in the western part of the island, but that caused the island to tip, so it was moved eastward. On that journey, parts kept coming off the lower rim, forming the mountains Lawu, Wilis, Kelud, Kawi, Arjuno and Welirang. The damage thus caused to the foot of the mountain caused it to shake, and the top came off and created Penanggungan as well. Indonesian Hindus also hold a belief that the mountain is the abode of Shiva in Java.

Floral problems

Foreign invasive plants

25 non-native plants have been found in Mount Semeru National Park. The foreign plants, which threaten the endemic local plants, were imported by Dutch botanist Van Steenis, in the colonial era. They include Foeniculum vulgare mill, Verbena brasiliensis, chromolaena odorata, and Salvinia molesta.

Vegetable plantations

Mud erosion from surrounding vegetable plantations are also making problem of silting of Ranu Pane Lake, which the lake becomes smaller and shallower. Research predicted the lake will disappear in about 2025 unless the vegetable plantations is replaced with a more ecologically-minded form of plantations.