|Environment and development
in coastal regions and in small islands
Coastal region and small island papers 2
Integrated Coastal Management (ICM)
DISCUSSION PAPER BY CHRIS NINNES
This paper briefly outlines basic strategies and methods that can be used to organize natural resource management within coastal zones. It describes the main economic activities of coastal zones based on living and non-living natural resources and suggests ways to organize their management within a holistic framework.
It is basic to coastal management to recognize how strongly activities in one sector or coastal region affect the activities in another sector or area. The sea is impacted by inland events such as effluent discharges in water courses, nutrient runoff from agricultural fertilizers and increased siltation as a result of deforestation. Similarly the sea also strongly affects the coastal zone. Storm events resulting in flooding or oil pollution carried into the coastal zone have considerable impact. Natural defenses (beaches, mangroves and coral reefs) are important in mitigating against storm waves and shore erosion.
The inter-relations between events in one sector and their impact elsewhere are also more subtle. Deforestation of lower hinterlands may not have an appreciable effect on coastal processes. Deforestation of upper mountain slopes exposes more fragile soils prone to erosion and greatly speeds up the flow of rainfall to the coast. This has two inter-related effects; increased erosion and a reduction in long-term water availability (both for agriculture and direct human consumption). A reduction in forest cover may also directly reduce precipitation through a reduction in both mist interception and air turbulence which promotes precipitation. Unsustainable forestry results in a reduction in economic activity, and displaced labour will migrate to other areas, either within the coastal zone or as urban migration.This results in increased pressure on other resources and the social problems of overpopulated cities.
The coastal zone issues and problems
The coastal zone may be defined as the area at the boundary between the land and the sea and may extend inland and seaward to a variable extent, depending upon the objectives and needs of the particular programme. For the purpose of the proposed pilot project, the boundaries extend seaward to the edge of the drop-off where waters become too deep for artisanal fishing (i.e. excluding offshore large-scale commercial fishing for pelagics and demersals) and landwards to include mountain watersheds.
There are a number of underlying factors resulting in overexploitation within the coastal zone. They can be broadly classified as being results of:
If coastal zones are to remain productive their management requires a holistic approach. This involves developing a multi-sector management programme so that all stakeholders and all concerned government agencies are involved. The importance of broad public support for development and management measures cannot be overemphasized.
The following main uses for the coastal zone, which point to the need for an integrated management framework, can be identified:
Coastal management in Haiti
A number of management and development issues can be suggested which, if addressed effectively, would probably contribute directly to the socio-economic well-being of the coastal population and to the general sustainable economic development of Haiti. Specifically (and in no particular order), these are :
The implementation of coastal resource management requires several national actions:
ICM programmes focus on the management of the physical development process using planning procedures and government regulations. Development planners, particularly, must recognize that modifications within the coastal zone can have adverse impacts throughout the entire zone (marine and terrestrial).
Resource management (fisheries, agriculture etc.) has already been mandated to various agencies, and there is no necessity to change this. Rather, ICM should be seen as a multi-sectoral process created to improve development planning and resource management through integration, co-operation and the co-ordination of activities.
Coastal management in the pilot project area must address the specific problems of common property and open access resources which result in over-exploitation. In this context, incentives to exploit sustainably are negated because:
Sustainable use should ensure that a resource will not be harvested, extracted or utilized in excess of the amount which can be regenerated. In essence, the resource should be seen as a capital investment with an annual yield; it is the yield that should be utilized and not the capital investment. The latter is the resource base, the sustaining of which assures annual yields in perpetuity.
Critical habitats and their management
The common property resources to be managed in the pilot project area are the fisheries and the forestry resources. Within these two domains are to be found a number of critical habitats that, because of their importance, require particular attention. These are:
Upland mountain forest
Because these resources are found in areas with high rainfall and steep slopes their removal does more to exacerbate erosion. These habitats also play a critical role in mist interception, another important source of water. Because of the importance of these habitats it is essential to plan for their immediate restoration through vigourous reforestation. Their future management will ideally be based on non-extractive practices.
Mid-range mountain forest
It is also important to maintain and enhance vegetation cover in these areas but their future management should be based on sustainable extraction geared to needs for fuel, building construction, furniture making and other commercial uses.
Adjacent: Mangroves in relatively healthy condition (La Gonāve Island). Below: Mangrove degraded largely by coastal water pollution (Port-au-Prince Bay).
Mangroves play a prominent role in the production of leaf litter and detrital matter which provides valuable inputs of carbon into the marine environment. They also provide physical habitat for many juvenile stages of commercial fish, crabs and lobsters, nesting sites for birds and important foraging grounds for juveniles and species that feed over inter-tidal mudflats. They also provide an important buffer against storm-surge and in stabilizing shorelines. In the study area mangroves are stunted (largely because of the lack of estuarine conditions) and play a lesser role than in many areas. They are, however, important in shoreline protection and their presence along the shores of some of the more intensely farmed coastal areas may be in recognition of this function. Management should seek to prevent destructive removal and possibly replant denuded areas.
These are found in shallow waters and are highly productive areas. The productivity stems from both their own growth and the productivity derived from the many epiphytes associated with them. Seagrass beds play an important ecological role, providing a substantial amount of nourishment, nutrients and habitat. They attract a diverse biota and are important nursery areas. They also help trap and bind sediments, but are damaged by excessive turbidity and pollution. In the study area, nearshore seagrass habitats are being severely impacted by sedimentation, and their future management will depend largely on reducing this impact.
These are also amongst the most productive systems in the world, largely because of their ability to extract limited resources from the surrounding waters and because of the reefs ability to recycle productivity within the system. Coral reefs have important economic outputs. They provide important habitats and resources for fisheries, support important tourist industries and form natural protective barriers against storm waves as well as providing beach material. They are highly susceptible to overfishing, sedimentation, pollution, discharge of large volumes of freshwater, physical damage (tourism and hurricanes) and eutrophication (from sewage and agricultural runoff). Coral reefs are not well represented along the shoreline of the study area, although they are more common around Les Arcadins Islands. The reefs that were observed demonstrated serious impacts from sedimentation; and considerable die-off had occurred. They were also characterized by an almost complete absence of common food fishes. Their future management relies on reducing sedimentation stress and improving fisheries management.
Classification of marine habitats within the pilot project area
Satellite imagery should be investigated as a means to provide resource inventory maps of the study area. Satellites collect data by measuring electromagnetic radiation. When electromagnetic radiation (generated by the sun or by the production of radar or laser waves) falls upon the earths surface some of the energy is reflected. Surfaces also naturally emit radiation, mostly in the form of heat (infrared radiation). The reflected and emitted radiations are recorded on either photographic film or by digital sensors carried on either a satellite or aircraft. Since the intensity and wavelength of this radiation are a function of the surface, each surface is described as possessing a characteristic spectral signature. If a sensor can distinguish different spectral signatures, it is possible to map the extent of such surfaces. Unfortunately, data derived directly from satellites are not packaged with neat labels indicating that this is a coral reef or this is a rain forest. Rather, the digital data must first be calibrated by collecting field data describing specific habitats. During the computer analysis of the digital satellite data the operator will input the field data, allowing the computer to identify all other areas with a similar spectral signature. Prior to this seminar, the author of this paper undertook field work (with Jean Wiener) to collect classification data of marine habitats. Three mangrove areas and nineteen marine areas (ranging from 2m2 to 45m2) were surveyed.
|Remote sensing and coastal
Features of interest to the coastal manager are often visible in satellite images. One can derive information such as spatial distribution of different habitats (submerged and terrestrial vegetation), ecological parameters (seagrass standing crop, mangrove leaf area index), changes in these habitats and parameters, and crude bathymetry
Satellite images taken above the Gulf of La Gonāve, from a report (October 1996) of the Centre for Tropical Coastal Management Studies (University of Newcastle upon Tyne, UK). The report assesses the availability and suitability of satellite imagery (Landsat TM and SPOT XS), for use in support of the management of Haiti's west coast.
These images are provided by courtesy of the author of the report , Dr. Edmund Green, of the World Conservation Monitoring Centre (firstname.lastname@example.org), a partner in these efforts. Information on pertinent literature is available.
Classification of data
In the study area mangroves were restricted to a narrow fringing band straddling the intertidal zone. Only dwarf forms of the red mangrove were observed, reflecting their largely marine habitat; in the absence of freshwater, Caribbean mangroves rarely attain appreciable heights. Mangrove height and density probably restrict their economic importance, when compared to many other regions where they are used for construction, charcoal production etc. They do, however, play an important role in shoreline stability, particularly from storm-surge.
They are found throughout the study area. Along the mainland they are restricted to shallow water (<3m), usually in front of the mangrove areas observed. Water turbidity probably prevents their colonization of deeper water. Mainland shallow-water seagrass beds would appear severely stressed by turbid water, being heavily coated by a film of sediment. In deeper waters (to 15m) the benthos was dominated by soft muds and a range of calcareous algae. In water deeper than 12m, algae density was sparse. The muddy bottoms were characterized by the presence of many (20/sq. m) polychaete and crustacean burrows. Occasional dead and dying sponges were observed at certain sites. A slightly deeper distribution of seagrass is found around Les Arcadins Islands, where water clarity is better. Seagrass beds were also associated with varying amounts of other marine algae, the marine algae predominating with increasing depth (<18m).
Coral reefs were poorly represented along the mainland coast. One small shallow (<3m) patch reef was observed in very turbid water. The reef was dominated by various species of the green algae Caulerpa (which prefer a firmer substrate) and the live hard corals (orders Milliporina and Scleractinia) present were severely stressed and/or dying from sediment load. Interestingly, the reef also had a number of soft corals (order Gorgonians) present; such were not observed elsewhere during this period of fieldwork.
A small fringing reef was surveyed at Trou Forban to 45m. Water clarity was good and the reef was in excellent condition.
Several reefs were also surveyed at Les Arcadins Islands. These were found in waters down to 12m and were dominated by hard corals and algae.
Throughout the marine classification work, habitats were characterized by an almost complete absence of medium to large food fish species. For many species (e.g. grouper and snapper) juveniles were also absent. This is highly indicative of overfishing and the uncharacteristic absence of juveniles suggests recruitment failure may also have occurred. A solitary lobster was observed at Trou Forban and six on a small patch reef to the north of Les Arcadins (four were immature juveniles, cephalothorax length = 35mm). Conch were generally absent apart from one site to the south of Les Arcadins where a number of juveniles were observed. No mature conch were seen.
Apart from shallow reef habitat around Les Arcadins and the fringing reef at Trou Forban, no other healthy reefs were observed. In fact, there appears to be a general lack of reefal habitat throughout the study area.
Future development and management inputs
Because of the extremely limited presence of coral reefs and large fish it is unlikely that significant dive related tourism will develop. The Caribbean is valued as a diving destination and the pilot study area would not compete alongside other destinations (and possibly other areas in Haiti not yet observed).
The limited amount of habitat available for many commercially important fishes and lobsters (despite there being a reasonable abundance of seagrass beds commonly used for foraging) does suggest that habitat enhancement could play an important role. Artificial reefs composed of vehicle and truck bodies could significantly enhance fish production. Port-au-Prince has an abundance of suitable material whose removal would also have beneficial aesthetic, health and road traffic spin-offs. Trials with artificial lobster habitats may also prove beneficial. As artificial reefs would add new habitat it may be possible to encourage fishermen to not fish certain reefs establishing small protected areas for possible stock enhancement. This is an issue worthy of discussion.
Mr. Ninnes was a UNESCO Consultant in Haiti; he also collaborated with the Centre for Tropical Coastal Management Studies, University of Newcastle-upon-Tyne, UK.
|UNESCOs CSI and the
Newcastle Centre are cooperating to further develop
training materials on the utilization of satellite
imagery in addressing coastal problems. The Centre is
producing a Remote-Sensing Handbook for Tropical
Coastal Management, to be published in 1998. A tool
in this venture is the UNESCO WinBILKO software,
available with training modules at: http://www.ncl.ac.uk/~ntcmweb/bilko/bilko.htm
The Newcastle Centre cooperates with various other partners in studies, funded by the UKs Department for International Development, to determine the potential economic benefits of remote-sensing technologies. Special emphasis is on the development and management of economically less-favoured countries (including those of the Caribbean region). Project activities are described at the Newcastle website: http://www.ncl.ac.uk/~ntcmweb/remote/ijrscasi.htm