Gunung Leuser National Park
Park entrance |
Gunung Leuser National Park is a national park covering 7,927 km² in northern Sumatra, Indonesia, straddling the border of North Sumatra and Aceh provinces. The national park, settled in the Barisan mountain range, is named after Mount Leuser (3,381 m), and protects a wide range of ecosystems. An orangutan sanctuary of Bukit Lawang is located inside the park. Together with Bukit Barisan Selatan and Kerinci Seblat national parks it forms a World Heritage Site, Tropical Rainforest Heritage of Sumatra.
Geography
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Location in Sumatra |
Gunung Leuser National Park is 150 km long, over 100 km wide and is
mostly mountainous. 40% of the park, which is mainly in the north, is
steep, and over 1,500 m. 12% of the park only, in the lower southern
half, is below 600 metres but for 25 km runs down the coast. 11 peaks
are over 2,700 m and the highest
point is Gunung Leuser, which 3,466 m
high
.
Ecology
Young Orangutan in the national park |
Gunung Leuser National Park is one of the two remaining habitats for Sumatran Orangutans (Pongo abelii). In 1971, Herman Rijksen established the Ketambe Research Station, a specially designated research area for the orangutan. Other mammals found in the park are the Sumatran elephant, Sumatran tiger, Sumatran rhinoceros, siamang, mainland serow, sambar deer and leopard cat.
After researchers put 28 camera-traps in July 2011, 6 months later
the researchers found one male and six females and predicted the
population is not more than 27 Sumatran rhinos which total population predicted is around 200 in Sumatra and Malaysia, a half population of 15 years ago.
Water supply
The first signs of reduced water replenishment have already been seen in and around the Leuser Ecosystem. Groundwater reservoirs are rapidly being exhausted and several rivers fall completely dry during part of the year. This has severe consequences for the local community. Both households and industries need to anticipate water shortages and higher costs for water.
The first signs of reduced water replenishment have already been seen in and around the Leuser Ecosystem. Groundwater reservoirs are rapidly being exhausted and several rivers fall completely dry during part of the year. This has severe consequences for the local community. Both households and industries need to anticipate water shortages and higher costs for water.
Fishery
Coastal fisheries and aquaculture in and around Leuser are very
important. They provide a large portion of the animal protein in local
people’s diets and generate ample foreign exchange. Their annual value
currently exceeds US $171 million. If the Leuser Ecosystem is degraded,
the decline in fresh water may have a detrimental impact on the
functioning of the fishery sector.
Flood and drought prevention
Flooding generally becomes more frequent and more destructive as a
result of converting forests to other uses. Annual storm flows from a
secondary forest are about threefold higher than from a similar-sized
primary forest catchment area (Kramer et al., 1995). In Aceh, local
farmers have reported an increasing frequency of drought and damaging
floods due to degradation of the watercatchment area. In May 1998, over
5,000 ha of intensive rice growing areas were taken out of active
production. This was the result of the failure of 29 irrigation schemes
due to a water shortage. Furthermore, floods in December 2000 cost the
lives of at least 190 people and left 660,000 people homeless. This cost
the Aceh province almost US $90 million in losses (Jakarta Post,
2000a). Logging companies are slowly recognising their role in increased
flooding and have made large donations to support the victims (Jakarta
Post, 2000b).
Agriculture and plantations
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Elephant jungle patrol near Tangkahan |
Agriculture is a major source of income for the local communities
around Leuser. Large rubber and oil palm plantations in northern Sumatra
play a major role in the national economy. Almost all remaining lowland
forest has been given out officially for oil palm plantations. Yield
decline has been recorded, however, in several Leuser regencies. This
decline can be ascribed mainly to a deterioration of nutrients in the
soil, along with soil erosion, drought and floods, and an increase in
weeds. Clearly, these causes of decline are linked to the deforestation
of Leuser. For example, the logging of water-catchment areas in Leuser
is found to be responsible for taking 94% of failed irrigation areas out
of production (BZD, 2000a).
Hydro-electricity
Several regencies, such as Aceh Tenggara, have hydro-electricity
plants that use water from Leuser. The plants operated in Aceh Tenggara
are designed as small-scale economic activities. It appears that the
operational conditions for the hydro-plants have worsened in recent
years. Increased erosion of the waterways has forced the operators to
remove excessive sediments from their turbines. This has led to frequent
interruption of the power supply, higher operational costs and damage
to the blades of the turbines. One plant closed down due to lack of
water supply. Most of these disturbances are considered abnormal and may
therefore be attributed to deforestation.
Tourism
Low-impact eco-tourism can be one of the most important sustainable,
non-consumptive uses of Leuser, thereby giving local communities
powerful incentives for conservation. Given the opportunities to view
wildlife such as orang-utans, some experts view eco-tourism as a major
potential source of revenue for communities living around Leuser (van
Schaik, 1999).
Biodiversity
People living in areas with a high biodiversity value tend to be
relatively poor. Hence, the highest economic values for biodiversity are
likely to be found within institutions and people in wealthy countries.
Funds can come from several sources, including bio-prospecting, the GEF
and grants from international NGOs (with donations possibly being
proportional to biodiversity value) (Wind and Legg, 2000).
Carbon sequestration
Anthropogenic increases in the concentrations of greenhouse gases
(such as CO2) in the atmosphere are widely believed to lead to climate
change. Carbon sequestration by rainforest ecosystems therefore has an
economic value, since the carbon fixed in the ecosystem reduces
atmospheric concentrations.
Fire prevention
To what extent does primary rainforest have a fire prevention
function, and thus an additional value for preventing economic damage?
There are various factors that make disturbed forest more prone to fires
than primary forests. The likelihood that a forest will burn depends on
the level of fire hazard and fire risk: (1) fire hazard is a measure of
the amount, type and dryness of potential fuel in the forest. Logged
forest has relatively large amount of dry logging wastes lying around;
(2) Fire risk is a measure of the probability that the fuel will ignite.
In the presence of abandoned logging roads, which provide easy access
to otherwise remote forests, the fire risk is greatly increased when
settlers use fire for land clearance.
Non-timber forest products
NTFP can provide local communities with cash as long as exploitation does not surpass a threshold level
Threats
In November 1995, the Langkat Regency
government proposed a road to connect an old enclave, known as Sapo
Padang, inside the park. In pursuit of business opportunities, 34
families who had been living in the enclave formed a cooperative in
March 1996 and subsequently submitted a proposal to develop an oil palm plantation in August 1997. The oil palm proposal was accepted by the regency and the head of the park agreed to the road construction.
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Park life |
In accordance to the government's Poverty Alleviation Program, the
oil palm project proceeded with 42.5 km² of clearance area, but the
project caused major forest destruction in the park during its
implementation.
The local cooperation unit formed a partnership with PT Amal Tani,
which has strong relationship with the military command in the area.
In January 1998, the Indonesian Forest Ministry granted a permission of
11 km road to be built. In June 1998, local office of the Forestry
Service issued a decree stating that the Sapo Padang enclave was no
longer legally a part of the national park, a controversial decision
which consequently led to further forest destruction during the road
construction and invited newcomers to slash and burn forest area to create local plantations a way deeper to the park.
In 1999, two university-based NGOs filed a legal suit to the Medan State Court, while a group of 61 lawyers
brought a parallel case in the National Administrative Court. In July
1999, the National Administrative Court rejected the case, while the
local NGOs won with 30 million rupiahs damage, but the legal process
continues with appeals. The legal process did not stop the project that extensive logging and
clearing, road-building and oil palm plantation continue operating
inside the national park.
2011 reports the pressures on locals from palm oil profits has led to illegal slash and burning of 21,000 hectares per year.
"Despite being protected by federal law from any form of destructive
encroachment, illegal logging is still rampant in the forest, with the
foliage of the Leuser ecosystem disappearing at a rate of 21,000
hectares per year."
Relocations
In December 2010, 26 families comprising 84 people were moved from Gunung Leuser National Park area to Musi Banyuasin, South Sumatra.
There are thousands of people who inhabit the park illegally, and the
Indonesian government plans to move them. Many of the inhabitants are
refugees from the violence and disasters in Aceh.