First publish : 8 December 2016

Administratively, the area of Mount Merapi lays within the area of Magelang, Boyolali, and Klaten District in Central Java, and to Sleman in Yogyakarta. The total size of Mount Merapi National Park is 6,410 ha, where 5,126.01 ha is located within the boundary of Central Java, and 1,283.99 ha within the boundary of the Special Region of Yogyakarta. The area was defined as Mount Merapi National Park (Taman Nasional Gunung Merapi/TNGM), as per the Decree of the Minister of Forestry No. 134/Menhut-II/2004 dated 4 May 2004. The national park holds a significant role for the people living in the surrounding area.

Water tower

Mount Merapi area is a water retention area that ensures the availability of water across the mount’s slope. Three riverflow areas (DAS) that receive water supply from Merapi area are DAS Opak, Progo, and Bengawan Solo.

Two of these three areas, namely DAS Progo and Bengawan Solo, benefit at least 1.7 million hectares of the surrounding areas. Most of the areas of DAS Progo belong to Central Java Province, which include Temanggung, Wonosobo, Magelang, Semarang, Boyolali, and Semarang, while the rest of them belong to the Special Region of Yogyakarta. Meanwhile, DAS Bengawan Solo covers 17 regencies and 3 cities in Central Java and East Java.

Fertile land

Mount Merapi is one of the most active volcanoes in Indonesia. The mountain’s volcanic activity provides fertility for the surrounding land on the slopes. The materials discharged when the mountain erupts contain a lot of nutrients, especially phosphor and potassium. The fertility of Merapi benefits the people living in its slopes as it allows them to plant various commodities, such as horticulture, fruits, coffee, and tobacco.

Threats to the sustainability of Merapi Area

Merapi is facing a threat of degradation in its function as life support. Natural disasters, illegal logging, and land conversion have caused tree population in the area to degrade. As the result, the soil gradually loses its ability to retain water.

The 2010 eruption has caused around 300 dead victims and damaged agricultural and road infrastructure, including farmlands. Every time it erupts, Merapi discharges approximately 50 million m³ of volcanic materials which cover farmlands.  Merapi’s eruption also damages water sources. The damaged water sources leads to the reduction of water debit that runs to the rivers flowing to Merapi’s slope areas. This makes it even harder for agriculture lands in Merapi slope to obtain water. As an example, 4,564 hectares of irrigation land in Magelang is facing the threat of insufficient water supply during dry season. Aside from eruption, cold lava flood also erodes riverbanks and causes sand deposit in certain locations.