|How can we solve this problem?
To increase production of food crops and livestock for local consumption, agricultural development is encouraged in many areas. Often this development is near coastal and riverine areas. Clearing of land or forests for food production may also be due to high levels of poverty in local regions. Poverty can often be linked to environmental degradation in many areas of the world. In addition, increasing numbers of people moving to coastal areas and increasing tourism are also reasons why construction activities in the coastal zone are being conducted, impacting local coral reefs. Reclamation in urban areas can also increase siltation onto coral reefs. Ports and harbor development along with dredging are necessary infrastructure on the coast which changes erosions rates and currents near coral reefs.
By supporting revegetation efforts for areas where mangroves and seagrass beds had been removed and by establishing buffer zones between coastal development and rivers, streams, and coastal waters, siltation rates can be decreased. In addition, supporting programs that help to improve the economic situations of local communities will also help break the cycle of poverty and environmental degradation. Lastly, land use planning and management of shorefront development will also help solve the problems caused by high siltation rates.
What can be done to solve this problem?
Understand the situation. Examine past and current attempts to solve this issue and whether these actions have been effective. You can get a sense of whether siltation is regulated by simply talking to locals in the community and government officials.
Link siltation with other management actions. Review the management questions in the Reef Check survey to identify whether there are management regulations in place and if they are being enforced. The goal is to bring all parts of society and government together to plan how coastal resources will be used or protected. To understand how actions by citizens and the government can be part of a joint effort to manage coral reefs, review the fact sheet on ‘Integrated Coastal Management’. In addition, review the fact sheet on ‘Marine Protected Areas.’ Marine protected areas are a tool that can be used as a part of integrated coastal management.
In Australia, many state governments are implementing watershed management programs which aim to reduce the loss of soil and nutrients from rural and urban areas. By using a variety of approaches including developing better farming practices and better use of fertilizers, revegetation programs, reduction of erosion by conservation of wetlands and mangrove habitats, the rate of siltation is being reduced in many areas.
What can a concerned citizen do to help?
There are several actions that any individual can do to help decrease siltation impacts on coral reefs. These include:
Provide educational materials to farmers, construction firms, and builders about the impacts their activities may have on mangroves and coral reefs. See Environmental Interpretation: A Practical Guide for People with Big Ideas and Small Budgets by S.H. Halm (1992) for ideas on how to prepare educational materials.
Implement educational campaigns that highlight the impacts that siltation has on corals and good practices that citizens can follow. For examples of good practices for improving water quality, see the University of Rhode Island’s Cooperative Extension at: http://www.uri.edu/ce/wq/program/html/SWAP.html
Maintain buffer zones if your land is adjacent to rivers, streams, and coastal waters. See "Vegetation Management and Landscape Design" in Guidelines for Low-Impact Tourism: Along the Coast of Quintana Roo, Mexico by C. Molina, C., Rubinoff, P., and J. Carranza (2001) available on-line at: http://www.crc.uri.edu/comm/lac_pubs.html. Also "Buffer Zones" by the U.S. EPA at: http://cfpub2.epa.gov/npdes/stormwater/menuofbmps/post_6.cfm
Initiate and participate in revegetation projects to replant mangroves and seagrass beds.
What can managers and decision-makers do to help?
In addition to the above management recommendations for a concerned citizen, resource managers and decision-makers may have additional means available to them to decrease the impacts that siltation has on coral reefs. These include:
Set sediment traps to measure siltation rates. See "Methods for Measuring Sedimentation Rates in Bottomland Hardwood (BLH) Wetlands" at: http://www.wes.army.mil/el/wrtc/wrp/tnotes/sdcp4-1.pdf
Make a rapid survey of existing mangrove cover and/or seagrass beds to monitor changes.
Monitor land use changes over time.
Create and maintain buffer zones and replant native vegetation. See “Vegetation Management and Landscape Design” in Guidelines for Low-Impact Tourism: Along the Coast of Quintana Roo, Mexico by C. Molina, C., Rubinoff, P., and J. Carranza (2001). Also “Buffer Zones” by the U.S. EPA at: http://cfpub2.epa.gov/npdes/stormwater/menuofbmps/post_6.cfm
Limit coastal development near sensitive reefs to decrease siltation during and after construction.
Implement catchment management programs, e.g. sedimentation basins for shrimp aquaculture, urban stormwater traps, dry retention basins. See “Stormwater and Surface Runoff” in Sustainable Coastal Tourism Handbook for the Philippines by Huttche et al. (2002) available on-line at: http://www.oneocean.org/download/
Prohibit ocean outfalls for mine tailings.
Implement extension programs for farmers and other land users that promote better soil conservation practices. For examples of good practices for improving water quality, see the University of Rhode Island’s Cooperative Extension at: http://www.uri.edu/ce/wq/program/html/SWAP.html. For information on how to develop an educational program, see Environmental Interpretation: A Practical Guide for People with Big Ideas and Small Budget .by S.H. Halm (1992).
Require shorefront construction to use mitigation practices that reduce siltation and soil runoff. See "Site Use and Design" in Sustainable Coastal Tourism Handbook for the Philippines by C.M. Huttche et al. (2002).
Improve land use planning that takes into account the effect of changing land uses on reefs.
|Poorly managed coastal infrastructure causes severe siltation eventually destroying the reefs.
Grand Terre, Mayotte (ARVAM, from ReefBase: http://www.reefbase.org)|