Coles and McKenzie 2005). Inappropriate coastal development or construction often result in beach erosion. Major impacts result from collecting beach sand for construction materials, construction of airports, hotels, and other structures too close to beaches or in offshore waters, and sand mining. In other locations in Indonesia (e.g., Seribu Islands and the coast of Bali), heavy coral mining and collection from reef flats have resulted in the deterioration of seagrass meadows (Humoto and Moosa 2005).
Other that negatively impact seagrass ecosystems include sewage discharge, industrial pollution, and overfishing. For example, there have been reports that dugong are disappearing from Cenderawasih Bay National Park because the shallow water seagrass meadows are being destroyed by trawl fishing as well as sedimentation resulting from deforestation (Putrawidjaja 2000). Most of these impacts remain localized and relatively small and can be managed with appropriate environmental guidelines. However, in the future climate change and associated increase in storm activity, water temperature, or sea level rise has the potential to damage seagrasses in the region or to influence their distribution.
All identified seagrass habitats have high ecological or economic value, whether supporting fisheries or biodiversity. Estuary/lagoonal and coastal habitats are considered to be the most threatened, due to extensive coastal development. However, the limited knowledge of deeper water seagrass habitats suggests that impacts on these habitats are extremely difficult to assess.
CONSERVATION
Currently there is no legislation in Indonesia that specifically stipulates that the function of seagrass ecosystems should be maintained (Indonesian Seagrass Committee 2002). However, seagrasses do not exist in nature as a separate ecological component and are often closely linked to other community types. Associations are likely to be complex interactions with mangrove communities, algae beds, salt marshes, and coral reef systems. Worldwide, many management activities to protect seagrasses have their origins in the protection of wider ecological systems or are designed to protect the overall biodiversity of the marine environment. The protection of seagrass habitat for species listed as threatened or vulnerable to extinction (e.g., Dugong and Green Sea Turtle), and their importance as habitat for juvenile fish and crustaceans which form the basis of economically valuable subsistence and commercial fisheries, have become motivating factors for the protection of seagrasses.
In Indonesia existing legislation relevant, directly or indirectly, to the management of seagrass ecosystems is considered sufficient for the adequate protection of seagrass ecosystems in the near future. However, there is an urgent need to reach common understanding regarding the vision and mission required to implement these laws in the field (Indonesian Seagrass Committee 2002). Law enforcement is still weak and ineffective; hence pollution and degradation of seagrass ecosystem continue to occur (Indonesian Seagrass Committee 2002).
The Indonesian Seagrass Committee in 2002 assessed many of the problems of legal aspects relevant to seagrass management in Indonesia and made a number of recommendations. These recommendations suggest that the following five steps be taken. First, an institution must be assigned specific authority to coordinate the campaign against pollution and degradation of the sea. Second, many legal acts (including Fisheries, Management of Living Environment, and acts concerning natural resources and their ecosystems) must be revised. Third, terrestrial spatial planning should be integrated with that of coastal areas and the sea on the basis of integrated ecosystems; Provincial and District/Municipality governments should designate new conservation areas in accordance with the land-use plan. Fourth, the division of authority between Provincial and District/Municipality governments in administrative aspects be publicized so that the management of ecosystems are assessed holistically and in integrated manner, and free of bureaucratic complications. Fifth, forest cutting, which directly affects coastal and marine ecosystems (including river banks, greenbelts of dams, lakes, rivers, and coast lines) be prohibited.
Implementation of such recommendations may require several approaches. Coles and Fortes (2001) separated these into three components: a prescriptive legal approach; a non-prescriptive broad-based approach ranging from planning processes to education; and a reactive approach designed to respond to specific issues, such as a development proposal. These approaches may overlap and be used simultaneously in many cases.
Prescriptive management of seagrass issues might range from local laws to a Presidential Decree. In Southeast Asian countries such as Indonesia and in the Pacific Island countries, protection is often strongest at the village or district level by government-supported agreements or through local level management (Coles and Fortes 2001). At the village level, successful enforcement is heavily dependent on community support.
While no international legislation specifically protects seagrass, there are international conventions that recognize the importance of wetlands and coastal areas, such as the Ramsar Convention on Wetlands. In some cases, seagrass meadows have been inadvertently protected because they are located within protected areas, such as Cenderawasih Bay National Park and Kamiali Wildlife Management Area. It is hoped that recognition of the global significance of areas such as Raja Ampat, which also include seagrasses, will also provide some degree of future protection.
Prescriptive management can include establishment of Marine Protected Areas (MPAs). A Marine Protected Area is an area of sea that is dedicated to the protection and maintenance of biological diversity and of natural and associated cultural resources, and is managed through legal and other effective means (IUCN 1994). A Marine Protected Area may be a ‘‘no-take’’ area like a terrestrial national park or it may comprise a multiple-use area, zoned in such a way to minimize conflicts and allow extractive activities to occur in specific areas. Establishing even a small Marine Protected Area is a complex process and includes a needs assessment and requires the involvement of all stakeholders and government agencies in defining a border and specifying permitted uses.
An alternate and complementary non-prescriptive approach is a Locally-managed Marine Area (LMMA). A Locally-managed Marine Area is an area of nearshore waters (including include coral reefs, seagrass meadows, mudflats, mangrove, and other areas) that is actively being managed by local communities or land-owning groups, or is being collaboratively managed by local communities together with local government and other partners based in the immediate vicinity. For example, Yayasan Rumsram, a nongovernmental conservation organization in Biak and the Padaido Islands, is pioneering the use of Locally-managed Marine Areas (LMMAs) in Indonesia through traditional marine resource management and customary prohibition (sasizen) practices.
Non-prescriptive methods of protecting seagrasses generally have a strong extension or educational focus. Providing information is important because it encourages and enables individuals to act voluntarily act in ways that reduce impacts on seagrasses. Actions in response to such information could range from being more aware of the downstream effect of poor agricultural practices to lobbying politicians for stronger sanctions against decisions that lead to seagrass loss. Non-prescriptive methods range from simple explanatory guides to complex industry codes of practice developed in negotiation with the industry in question (Coles and Fortes 2001).
Reactive processes generally occur in response to a perceived operational threat, such as a coastal development proposal. Reactive processes can also include risk management plans that identify areas of seagrass to be protected in the event of an impact (e.g., oil spill or ship grounding). Reactive processes are generally identified in environmental impact statements, which also propose strategies (e.g., redesign, response, or by reducing future risk) to minimize the effects of a development or structure on the coastal environment, including seagrasses. The combination of project redesign in response to environmental impact statements and reactive environment management systems can provide enormous improvements to coastal seagrass protection.
Discussion
A key step in protecting seagrasses in this region will be to obtain better distributional and abundance data and to develop a better understanding of seasonal changes and local ecosystems. At the present time information is patchy
