Mangrove Care Forum Bali

Indonesia is an archipelagic country with more than 17,000 islands and 95,181 km of coastline, of which about 6,000 islands are inhabited by over 238 million people. In the 1980s, there are more than 4.2 million hectares of mangroves but half of that coverage has been lost by the end of the 1990s. For centuries, the Indonesian people have relied on the resources provided by the mangroves, for firewood, charcoal, tannin, dyes, food and beverages, medicine, pole and timber. In the early days of commercialization, fishing and charcoal production made the basic economic activities. Now, millions of hectares of mangrove forests are lost to agriculture, oil palm plantations and fish farms, making coastal communities vulnerable to the force of tropical storms and loss of livelihood and products.

In 2011, the Meteorology, Climatology and Geophysics Agency (BMKG) detected 23 tropical cyclones off the coast, which produced high speed winds, heavy rains, and storm surges that caused flooding and structural damage to buildings and coastal infrastructure. Mangroves are adjacent to major landmasses and big rivers in Indonesia, and mostly found on the coasts of large islands of Sumatra, Kalimantan, Sulawesi and Papua. The island of Java, where approximately 130 million people live, is particularly vulnerable to tropical storms.

In 2007, the Indonesian Forestry Ministry established 2 centres for mangrove development. During 2010 and 2011, the centre on the island of Bali planted 8,000 new mangrove trees, and the other centre, in the city of Medan on the island of Sumatra, put in 10,000 new plants. These efforts paled against the continual destruction of the coastal forests in the name of urban development, mainly for agricultural expansion. The realisation and urgency that we need to step up efforts in preserving the mangrove forests is what led to the formation of the Mangrove Care Forum Bali.^[4][5]

The Ngurah Rai Grand Forest Park is a vast green area located in Benoa Bay. The coast is filled with diversity in nature’s ecosystem, including but not limited to:

• 66 species of Makrazoobentos (Nassarius luridus, Clypeomorus coralium and Nerita antiquate)
• 45 species of Fish (Teraponidae, Belonidae, Muraenidae)
• 36 species of Birds (Accipitridae, Laridae)
• 27 species of Plankton (Skeletonema costatum, Podon)
• 16 species of Mangrove Trees (Ceriops tagal, Avicennia marina)
• 5 species of Reptiles (Komodo dragons, vipers, mamba)
• 3 species of Mammals (Brandocota indica, Pteropus edulis)

Benoa Bay is a tidal estuary located on the southeast coast of Bali. The estuary is protected by the narrow sandy Benoa Peninsula which protrudes northwards from the southern tip of the harbour and which closes off the entire southern portion of the estuary. Serangan Island which is located to the north partially closes the remainder of the estuary except for a one kilometre navigable stretch of water that separates the southern tip of the island from the Benoa Peninsula. The northern tip of the island is separated from the mainland at high and mid tides by a very shallow straight which is 400 metres at its narrowest point. The entire coastline is protected by an extensive coral reef system that runs continuously apart from a very narrow (200 metre) channel at the harbour entrance at the northern tip of the Benoa Peninsula.

The human feature of the Bay is the Benoa Port facility located on reclaimed land in the middle of the estuary, and the connecting causeway that stretches 3 kilometres north to the mainland. The causeway being a solid barrier has greatly affected the natural flushing of the bay by tide and stream discharge. Benoa Bay is lined with a mangrove forest that has suffered depletion due to development and land reclamation. Estimates are that 50% of the mangrove forest has been lost since 1980 as a result of development. There are many fresh water rivers flowing into the estuary, predominantly those draining the central plains and mountain ranges to the north, and to a lesser extent from the southern Bukit Plateau.

Benoa Bay suffers from a number of serious environmental problems and in a sense, similar to other estuarine environments, is a focal point for environmental impacts that originate elsewhere in the region. These problems range from eutrophication of the estuary due to nutrient loading through to biological pollution from untreated sewage effluent discharge.

Three of the fresh water rivers that enter Benoa Bay from the north originate in the agricultural heartland of Bali and reach the estuary after travelling through the highly populated urban centre of Denpasar. Agricultural runoff is particularly high in nutrients from fertilisers and manure from farm animals. In particular crop applications of urea, triple super phosphate and potassium chloride, as well as growth stimulant ZA are common in the catchment area. Fertilisers that are not directly absorbed in the rice fields are carried down through the irrigation system and eventually through rivers and out into the bay. All of the rivers entering the bay have large quantities of excess nutrients and the nutrient loading of the bay is evident with the visible growth of algae and uncharacteristic sea bed grasses.^[6]

• http://arthagrahapeduli.org/
• https://web.archive.org/web/20130719063054/http://tamblingwildlife.com/