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| Outcomes Introduction Case study Revision More |
Jennifer Curtis Access Asia Coordinator Professional Support and Curriculum Directorate, DET |
The student:
| H2 | explains the factors which place ecosystems at risk and the reasons for their protection |
| H5 | evaluates environmental management strategies in terms of ecological sustainability |
| H6 | evaluates the impacts of, and responses of people to, environmental change |
| H7 | justifies geographical methods applicable and useful in the workplace and relevant to a changing world |
| H10 | applies maps, graphs and statistics, photographs and fieldwork to analyse and integrate data in geographical contexts |
| H12 | explains geographical patterns, processes and future trends through appropriate case studies and illustrative examples. |
Extract from Stage 6 Geography syllabus. © Board of Studies NSW 1999.
The operation of an ecosystem depends upon linkages that exist between the components of the biophysical environment: the atmosphere, hydrosphere, lithosphere and biosphere.
Generally, ecosystems change because of location, extent, biodiversity and linkage.
Ecosystems change when they are controlled or disturbed. This may be the result of human or natural factors and may be intentional or inadvertent. Intentional changes can produce a number of unforeseen consequences, which creates the need for responsible management.
The management strategies needed to protect ecosystems (including those used by indigenous peoples) are at a local, national, regional, continental and global level.
The management strategies to preserve and conserve ecosystems at risk recognise the need to manage whole ecosystems. This may involve strategies that range from total preservation to sustainable development.
Management strategies change over time. This is due to changes in environmental quality, technological advances, economic, social and political attitudes.
Ecosystems have a range of values that are dependent upon the maintenance of genetic diversity, between and within ecosystems. These values may be: economic, e.g. present and future use of resources, social, e.g. intrinsic value and environmental, e.g. protecting land and water resources and permitting natural change to proceed unhindered.
The Sekonyer River, Kalimantan, Indonesia
Kalimantan, Indonesia
The Sekonyer River flows into Kumai Harbour in Southern Kalimantan from deep in the rainforests of Kalimantan. The area is remote and the rainforests and wildlife are spectacular beside the river as you pass through Tanjung Puting National Park. Tanjung Puting is a national park that covers 3550 square kilometres in area of low-lying alluvial land on the southern coast of central Kalimantan, with the highest elevation just eleven metres. Around one-third of the vegetation is tropical rainforest.
Tanjung Putting National Park

Tanjung Puting is particularly known because of its orang-utan rehabilitation centre, Camp Leakey, located on the eastern tributary of the Sekonyer River, one of three rivers that run through the park.
Orang-utan
Along the Sekonyer River men are seen fishing from small dugout canoes, children play at the water's edge and women draw water from the river for their daily needs.
As you float slowly along the river in the old longboat (kelotok), you are struck by the muddy brown colour of the water and wonder why the water is so polluted.
Polluted waters
If you talk to people who live along the Sekonyer River you will be soon told about the gold mine upstream. The Aspai is a gold mine operation that provides a meager livelihood for one hundred families or more. Most of these families have migrated from Java with government assistance. It appears there are no official land claims and each group works independently without due consideration for government regulations on environmental, health or safety conditions.
Miners - open cut mine
Profile: Sukerto has come from Madura, east Java, to look for gold. He is one of a six-digger team, working deep in a sand pit ten metres deep and twenty metres wide. When the gold has been exhausted in one hole, the team starts another one upstream. There are more than a dozen pits in Aspai. Aspai is one of nine scattered sites, with 2 000 to 3 000 prospectors in total, working along the Sekonyer River. Sukerto sells his gold for 60 000 rupiah (A$15) per gram and earns approximately A$100 per month.
The gold mine commenced operation in 1989 and the damage it has caused since then has been devastating for the local communities living along the Sekonyer River. If you travel up the tributaries that have not been affected by the gold mine operation, you can see the clear waters, the way it would have been along the full length of the Sekonyer River before mining began. The mining operation is a dangerous sluicing, alluvial process in the sand dunes that have been previously clear-felled for timber.
Mine - cleared sand dunes
The process: Sukerto and his team pump water from the river. The pump-driven water pipe shoots out sand from beneath the surface. The surging water and sand are directed down a three metre carpeted slide at the rim of the pit. The sand and water run off the end of the slide but the grains of gold and other dirt particles are caught in the carpet's fibres. At the end of the day, the material caught in the carpet is rinsed onto a metallic pan and combined with mercury. The gold and the mercury bond together but the sand and water are rinsed away. Sukerto and his team find about three grams of gold per day, using this process.
As a result of the process of digging for gold the prospectors are turning over the ground and this has led to the loss of topsoil nutrients, creating sand dunes and the impossibility of re-vegetating the area. The huge pits which have been washed away with high pressure hoses are the origin of the heavy sediment load in the river. In addition to the silt problems, the release of mercury residual has been responsible for at least two major fish kills in recent years as well as making it dangerous for all wildlife and human beings that come into contact with this mercury residual.
Polluting the river at Aspai

Another contributing factor to the river's pollution is the use of speedboats to transport everything between Kumai Harbour and the Aspai: people, food supplies, bulk fuel and equipment for mining. The continuous use of speedboats, which stir up the water, leaves oil in the water and dislodges vegetation on the banks, compounds the problem of sediment in the river.
Sadly, many of the workers and their families are not originally from the area and they do not understand what they are doing to the Sekonyer River but more importantly, do they care?
Mining activity occurs without permits. The Indonesian authorities have confiscated mining equipment and evicted miners. However, because of the desperate nature of their lives and those of the families they support, they return and continue to mine for gold.
Recognising the need to conserve its rich biological diversity, the Government of Indonesia has made a commitment to protect ten per cent of the country's land area and, eventually, some 200 000 square kilometres of coastal and marine habitats as conservation areas. Indonesia has currently 366 established conservation areas including 26 national parks of which Tanjung Puting is one.
An estimated 12 million people live in and around the forests of Indonesia. Obviously protection alone is not enough to secure the future of these areas; they need to be managed for the large number of people that inhabit the area.
Historically, the needs and desires of local communities, who were frequently better managers of these resources than other people since they often depended directly on them for their survival, were often neglected in the decision making process. Recently, however, the need to involve local people in decisions concerning the management of forested areas has become more obvious. Initiatives to link development and environmental protection have emerged in Indonesia and have been widely welcomed by rural communities.
Environmental Investigation Agency - Forest campaign
www.eia-international.org
Rainforest Action Network
www.ran.org ![]()
Orang-utan Foundation International
www.orangutan.org ![]()