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Coral Reef, Seagrass Beds and Working paper Mangroves: Their interaction in UNESCO/W.I.L.-F.D.U./ the coastal zones of the Caribbean. IOCARIBE Workshop. West Indies Laboratory, Fairleigh Dickinson University St. Croix, U.S.V.I. 24-30 May 1982 LIN MANGROVE FORESTS: ECOLOGYAND RESPONSE TO NATURAL AND MAN TNDUCED STRESSORS COASTAL ZONE INFORMATION CENTER SD- 397 .M25 Document prepared by Gilberto Cintr6n, Director of the Marine Resources C56 Division, Department of Na tural Resources of the Commonwealth of 1982 Puerto Rico, and Yara Schaeffer-Novelli, Instituto Oceanografico Univer- 3idade de Sao Paulo, Brasil. Document prepared for use by workshop participants CONTENTS Pa ge 1. INTRODUCTION I 2. DEFINITION I 3. DISTRIBUTION 2 4. SPECIES 4 5. ADAPTATIONS AND ZONATION 4 6. ZONATION AND SUCCESSION 7 7. PHYSIOGRAPHIC TYPES 9 7.1 Riverine forests 10 7.2 Fringe forests 10 7.3 Basin forests 11 7.4 Dwarf, forests 12 8. PRODUCTIVITY 12 9. DECOMPOSITION AND UTILIZATION OF LITTERFALL 13 10. FISHERIES 15 11. CLIMATIC CONSTRAINTS ON DEVELOPMENT 16 12. VULNERABILITY TO STRESSORS, 18 12.1 Natural stressors 19 12. 1. 1 Tropical cyclones 19 12.1.2 Tidal waves 23 12.1.3 Eustatic sea level rise and coastal erosion 23 12.1.4 Hypersalinity 24 12.2 Man induced stressors 27 12.2.1 Channelization 27 12.2.2 Impoundment 27 12.2.3 Sedimentation 28 12.2.4 Thermal pollution 29 12.2.5 Oil 30 12.2.6 Mining 33 I I Contents (Cont.) I Page 13. RECOVERY 33 1 14. CONCLUSION: CONSERVATION NEEDS 37 1 15. BIBLIOGRAPHY 39 1 - I I I I I I I I I I 1. INTRODUCTION Until very recently, mangrove swamps were seen as mosquito- infested wastelands, unfit for most uses, but convenient sites for open dumps and sewage discharges. Mangrove management meant "reclama- tion, " either for agricultural purposes or housing developments. Mangrove forests are, however, among the most productive ecosystems on the planet. Their daily rate of organic matter fixation (" 20 g.O.M./m2-day) is about 70 times the maximum value reported for tropical oceanic waters and 6 times the mean for the rates reported for marine flagellate blooms in neritic waters in the Caribbean (Ryther, 1969; Burkholder et al., 1967). Because of this high rate of production of organic matter, they are able to sustain important and valuable populations of fish, shellfish and wildlife and are prime breeding and nursery grounds for many species. The main reason that mangroves have been consistently undervalued and poorly managed in our region is the lack of available information about the resource, its role and vulnerability. In this paper, we summarize some basic information about the ecology of these forests in our geographic region. 2. DEFINITION The word mangrove is employed to describe a group of plants adapted to colonize waterlogged anaerobic and saline soils. They grow as trees or shrubs along most tropical estuaries and sheltered shores. The term is 2 also used to describe the complex a ssamblage of animals and other plants a s socia ted with this- forest type. 3.' DISTRIBUTION Mangroves are limited on a global scale by temperature and their lack of tolerance to frost. They extend latitudinally beyond the tropics, reaching in places to 29-301n both hemispheres. At these latitudes, the mean monthly temperature for the coldest month is between 15 and 1611 C, the mean annual temperature is 20-221 C and the annual temperature amplitudes range from 8-131 C. Frosts occur periodically at these areas and at the latitudinal limits the mangrove forests are poorly developed and grade into salt marshes dominated by herbaceous vegetation. Black mangroves (Avicennia sp.) are most frost tolerant and have the widest latitudinal range. Within the warmer portion of their range temperature is not limiting but the following other factors remain to be determinants or modifiers of their degree of development and areal coverage. Suitable Physiograph : Mangroves develop in low lying areas subjected to saline intrusions. They develop best where topographic gradients are very small and saline intrusions penetrate far inland, for example on broad coastal plains. Presence of salt water. Mangroves are not obligate halophytes but salt water removes the competition from plants that lack adaptations to deal with salt. 3 Large tidal amplitude: Tidal intrusions force salt wedges into the low lying areas. Where the tidal amplitude is large and the topographic gradient small, the mangrove belt may reach several kilometers in thick- ness. Precipitation in exce-ss of evapotranspiration (P > PET); Mangroves develop best in moist regions where there are fresh water surpluses. This results in abundant land drainage and extensive development of forests in the areas subjected to sa line - intru s ion s River discharge Rivers are important geomorphic agents that shape the earth's surface and create deltaic features over which mangroves develop. In some regions their discharge may allow mangroves to develop in very *dry regions where evapotranspiration greatly exceeds precipitation. In these areas, mangroves develop as riverine forests backed by extensive salt flats. Mangroves may develop in areas where there are no permanent A river discharges (coastal fringes), but their development in these areas is. limited,... The absence of river discharges can -be- mitigated by.the availability of runoff or fresh water upwellings. Shelte Mangrove seedlings and mature trees are vulnerable to uprooting by waves and current scour. They therefore develop best in low energy environments. They reach the sea only on protected segments of the coast, on the lee of offshore reefs, shoals or other protective struc- tures. They line sheltered estuaries and coastal lagoons. 4 Availability of allocthonous sediments: Sediments from outside area sare essential for land building and encroachment. Terrestrially derived sediments bring nutrients that are incorporated by the plants. Although mangroves may develop in areas where there are very low alloc- thonous sediment inputs, @the best developed forests are those of riverine environments that are subjected to periodic deposition of silts. 4. SPECIES In contrast to the Indo-Pacific region, where mangroves are thought to have originated, and where there are some 44 species, in the Caribbean region only seven species are present. These are the red mangroves Rhizoph mangle R. harrisonni and R. racemosa; the black mangroves Avicennia germinans and A. schaueriana; the white mangrove Laguncularia racemosa and the buttonwood Conocarpus erecta. Of the red and black mangroves, only R. mangle and A. germinans are widely distributed in the Caribbean. The iabt two species, racemosa (white mangrove) and C. erecta (buttonWood) are found throughout the region. The buttonwood is considered a peripheral species and quite often is found in coastal nonmangrove associations. 5. ADAPTATIONS AND ZONATION Several environmental factors determine the position of individual species in a forest. For instance, in a fringe one may observe variations in terms of tidal exposure, salinity gradients and different soil types and 5 textures with distance inland. Each species has adaptations that allow it to cope best with the site's factors with the least metabolic cost. This means that more energy can be alloted for growth and reproduction allowing that species to become highly competitive and ultimately dominant. This may lead to an observable zonation of species in a man- grove stand. Red mangroves are usually found at the outer edges of a fringe or bordering tidal creeks and channels. This species has a large propagule (seed) that can reach some 30 cm long and weigh [email protected] g. Upon settle- ment the sapling quickly develops supporting roots that protect the young plant from washout. This prop root system is surprisingly responsive to the environment (Gill and Tomlinson 1977). Very complex prop ro ot mazes develop in some fringe forests, possibly as a response to wind and wave stresses. The trees growing on more stable substrates often develop very erect boles and have proportionately fewer prop roots. These character- istics: the ability to become implanted ixi. deeper water (up to.30 cm) and to windstand dislodgement by water movement, contribute to allow this species to become dominant in the outer fringes. Red mangrove has a low tolerance to high salinities. It actually develops best at low salinities (10-200/oo) but will form forests, even where salinities reach 50-55'Yoo. These salinity levels are very close to the limits of its tolerance, and growth and development are poor under hypersaline conditions. 6 Black and white mangroves tolerate higher salinity levels and thrive in higher salinity substrates with a greater metabolic efficiency (Carter et al. 1973). These species are typical of.the inner swamp where tidal flooding is less frequent and evapotranspiration contributes to accumulate salts. Black mangroves, are the most salinity tolerant. Scrub forests are found in soils with interstitial salinities of 90961o. Well developed forests are found where interstitial salinities are 60-65961o. Although white man- groves are also fairly tolerant of high salinities, they seem to do best where these are not so high. In general, in tropical areas, where there are ample fresh water flows and interstitial salinities are low, the white mangrove dominates. In areas where there are pronounced drought periods and salinities are high, black mangroves may be dominant. The relative stagnation of water in basin forests requires special adaptations to allow ventilation of the root system. Black and white mangroves, have adaptations. to overcome this.problem. They.ventilate their root system by producing networks. of chimney-like organs (pneumatophores). These arise from the root and project from the soil and the stagnant water surface. The surface of the pneumatophore has minute pores through which gas exchange takes place. In this way oxygen diffuses down to the root and carbon dioxide is vented out. These pneumatophores reach 10-30 cm in length depending on the site's flooding levels. They are never totally flooded for extended time periods 7 since this would result in the eventual death of the tree. These species also have small seeds. This is advantageous since the floating propagules can be disseminated by the weak water flows typical of these areas. The movement of small seeds is not as easily hampered by the profuse growth of pneumathophores. Because of the smaller size of the propagule, the implantation depth is more restricted (10-15 cm). In general black mangroves appear to tole- rate deeper and longer flooding than white mangrove. In this respect, black mangroves'may be dominant in low salinity environments subjected to large seasonal changes in water level. The buttonwood is a peripheral species. It has a low tolerance to salinity but can stand flooding by very brackish waters , usually where the salinity is less than 5516o. It does well in sandy or rocky substrates and may be found in areas that are not flooded. A few pure stands of Conocarpu s occur in Puerto Rico in permanently flooded basins where salinity. is Jess. than 55,c'o 6. ZONATION AND SUCCESSION It has been suggested that the zonation observed in a mangrove swamp is the result of a succession of species (Davis 1940, Macnae 1968). According to Davis , the red mangrove is the pioneer species that prepares the way for the others. As this species progressively grows toward the sea , accretion takes place, and in the inner parts of the prograding fringe it is replaced by the black mangrove. Eventually, 8 black mangrove is also replaced by the white mangrove, which gives way to buttonwood or fresh water swamps. This scheme suggests that man- groves are the 'causal' agent of coastal progradation. It now appears that mangroves are not the cause of the rapid accretion but that they are responding to coastal accretionary patterns. In this sense-they contri- bute to stabilize rapidly accreting banks and shoals but the extent to which they promote accretion is uncertain '(Bird 1976). Davis' scheme is applicable only in some instances where sedi- moint inputs are high and there is active coastal progradation and freshwater runoff, since in some areas the landward succession could be arrested by dry conditions. In areas where there are no large fresh- water and sediment inputs , as in most of the dry portions of the Caribbean islands, mangroves develop over autocthonous peats. Progradation under these circumstances is very slow and may be surpassed by the known rise in sea level which is estimated to be some 3 mm/yr (Emery 1980 as cited byTtkins and Epstein 1982). . In most instances , mangroves have retreated landwards due to the submergence of land masses during the Holocene transgression. Zonation patterns in these sediment starved areas are a response of the various species to environmental factors and do not necessarily 'recapitulate' successional patterns. An analysis of old aerial photography (1936) to ascertain the patterns of establishment after a hurricane in southwest Puerto Rico (Cintr6n et al. 1980a) shows that there has been little or no peripheral accretion. 9 Suitable areas were immediately recolonized and the present zonation pattern'did not result from a successional of species. 7. PHYSIOGRAPHIC TYPES Mangrove forests vary greatly in their structural development. This structural variability is the response of the trees: to the sum total of particular environmental factors, each of which can vary both in intensity and in frequency of recurrence. Individual forcing functions , or environ- mental factors , that control mangrove structure include tidal fluctuations (with daily, monthly and annual cycles), runoff and groundwater perio- dicity (usually over annual or longer cycles) , nutrient inputs (usually tied to runoff hydroperiods) , droughts (sometimes over periods of several years) , soil salinity, etc. It is not usually possible to quantify all these factors to describe the so-called "energy signature" of each stand. Snedaker and Pool (1973) and Lugo and Snedaker (1974) developed a clas- sification scheme that grouped mangrove forest types in units in which t.he.-ma-jor''for-ding fun-ctions -operate at similar levels within each unit. Because of this , forest types within each unit share similar structural characteristics. Originally these authors recognized five types : (1) fringe forests , (2) riverine forests , (3) overwash fore s ts , (4) ba s in forests (including hammocks) and (5) dwarf forests (Lugo and Snedaker 1974). More recently, after a review of all the available quantitative structural data available, we simplified the previous scheme by i ncor- porating overwash forests as a type of fringe and considering dwarf 10 forests a type of basin. The description of these forest types , taken from Cintr6n et al. (1980) and Cintr6n and Novelli (198 1) , follows: 7. 1. Riverine forests Riverine forests develop along the edges of river estuaries , often as far inland the toe of the.saline intrusion. In this environment water flows and nutrient inputs are high. Flood waters bring in silts and mineral nutrients and these are rapidly incorporated into plant tissue. On the periphery of the forest, an area of high kinetic energy due to tidal motion and river discharge, the dominant species is Rhizophora. sp. , which develops a complex maze of adventitious roots. This root maze allows the establishment of well developed trees in spite of the strong water flows. Inland from the fringe one finds stands of Laguncularia sp. and Avicennia sp. Usually, riverine forests are most luxuriant in the lower and middle part of the estuary. Generally, inter- stitial salinities in these forests are lower than in the other types. They are lowest at times of flood when the salt wedge is driven seaward. During times of low flow, salt intrudes into the innermost parts of the estuary, raising the salinity temporarily. Usually interstitial salinities are in the range of 10-200/oo or less. 7.2. Frincie forests Fringing mangroves develop along protected shores , over shoals or spits , often forming overwash islands. Fringes usually have pronounced gradients in topography, turbulence and tidal amplitude. Damping of the variation in tidal amplitude and turbulence inside the stand may result in high interstitial salinities in the inner parts of the fringe. There, the soil elevations are high and the terrain is less often flooded. In these inner portions Avicennia sp. may become dominant. On the outer edge where the levels of kinetic energy are high Rhizopho sp. dominates . Interstitial salinities in the outer fringe are just above ambient sea water (39 � 1.39o'o) , but increase to higher levels (59 47w) in the Avicennia sp. zone (Cintr6n et al. 1980a). 7.3. Basin forests Basin mangroves are characterized by sluggish laminar water flows over wide areas of very small topographic gradients. The water turnover rate is slow. Basins receive and store water seasonally. Because of the uniform sheet flows strong salinity gradients do not develop within the basin. Basin forests may be dominated by either Laguncularia sp. or Avicennia sp. , although mixed stands may be found. Tidal creeks and drainage channels within the basin are often lined with Rhizophora sp. Avicennia sp. dominates in basin forests where high salinities prevail (> 50%) , whereas Laguncularia sp. dominates in low salinity basins . Mixed forests are found at intermediate salinities (30-400/0'). The structural characteristics of basin forests depend on the hydro- period. Where flows are weak but constant, forests develop well. In stagnant basins there may be oxygen depletion, slow nutrient recycling and reduced growth. 12 7.4. Dwarf forests Dwarf forests occur where growth is limited by edaphic factors. Stands of dwarf Rhizophora mangle develop in some areas of the Caribbean over peat substrates in basins that do not receive substantial amounts of terres-trial runoff. Mature red mangrove trees in these basins are usually less than 2 m tall and often are about 1-1 1/2 m in the inner parts of the stand. Dwarf stands of R. mangle develop over marl in Florida, USA. It appears that in both instances (growth over peat and marl) the plants are being subjected to nutrient deficient (oligrotrophic) conditions. Dwarf stands of Rhizophora are known from Puerto Rico, St. Thomas (U.S.V.I.), and Paso de Cattlan in the Dominican Republic. Dwarfed black mangroves are often found on the landward side of fringes and basins in seasonally dry areas , immediately adjacent to salt flats or hypersaline lagoons. The dwarfing factor here is extremely high levels of salt in the soil. 8. PRODUCTIVITY Table 1 is a summary of productivity data from Lugo and Snedaker's (1974) review. The data have been converted from gC/m2-day to grams of organic matter/m2 -day and presented by forest type. These numbers were obtained from gas exchange studies and represent total community metabolism. Riverine forests show very high rates of gross production (24g 0. M./m2 -day), followed by basins (18g 0. M./m2 -day), and fringes (1 3.2g 0. M. /m2 -day) . Net , production is the amount of organic 13 matter left after metabolic losses are accounted for. This is the amount of organic matter available for growth, foliage and seed production. These rates are also high. Between 20 and 40% of net production is partitioned for the production of leaves , flowers , fruits and stipules, which constantly fall to the,forest floor. Litterfall rates (dry weight) are highest in ri verine forests (2.94 - 3.96 g/m2 -day), slightly less in fringe forests (2.0.g/m2 day) and intermediate in value in basins (1. 9 - 2. 3 g/m2 -day) (Pool et al. 1975). Well developed riverine forests in Puerto Rico have litterfall rates averaging 4.12 g/m2 -day (Negr6n 1980). A monospecific black mangrove basin in Puerto Rico averaged 2.29 � 0.30 g/m2 -day (Negr6n and Cintr6n 1981). Litterfall rates in Avicennia sp. , Rhizophora sp. , and Laguncularia sp. stands in Guadeloupe were 3.56, 4.33 and 2.74 g/m2 -day, respectively (Febvay and Kermarrec 1978). 9. DECOMPOSITION AND UTILIZATION OF LITTERFALL It is now recognized that one of the primary reasons mangrove areas are so important is because of their high rates of productivity of organic matter as litter. This material falls to the forest floor where it starts to decompose. During this time soluble organics are leached out and the leaf surfaces are colonized by fungi and bacteria. In time a complex meiofaunal assemblage develops, grazing on the decomposers. The decomposing material, originally high in carbohydrates and low in proteins , becomes enriched with microbial protein. The C:N ratio of the 14 plant material decreases during decomposition. In R. mangle the C:N ratio decreases from 90,6 to 40.7 during the first 70 days of the decom- position process (Cundell et al. 1979). These low C:N ratios indicate the greater nutritional value of the decomposing material. As a result of decomposition, and the intense activity-of grazing organisms the plant material is gradually reduced to very small particles. These detrital particles enriched with microbial tissue, are consumed by detritivores. These derive their nutrition primarily from the microbial and meiofaunal assamblage associated with the detrital particle. Once consumed, the particle is stripped of its microbial and meiofaunal cover and egested. The undigested stripped particles may become recolonized by microbes, repeating the cycle anew until all the digestible components are utilized. As stated earlier, the initial autolysis of the plant material releases large amounts of dissolved organic matter to the water. This DOM is an important component of the outflux from mangrove areas, especially from basins where tidal and freshwater flows are too weak to export particulate matter. Bacteria are known to be important in the uptake and utilization of DOM. Prackash (1971) has shown thatblooms of the bioluminescent dinoglagellate Pyrodinium bahamense are stimulated by humic substances from mangrove areas . These humic substances also enhance the produc- tivity of other neritic diatoms such as Skeletonema costatum and Thallassiosira nordenskioldii (Prakash et al., 1973). Thus, there is evidence that the waters leaching from mangrove areas appear to be rich in biologically active substances which can stimulate or regulate phyto- plankton production in adjacent waters. 10. FISHERIES Given the continuous availability of large amounts of nutritious organic matter in mangrove lined areas , it is not surprising that large numbers of organisms aggregate and utilize it. The sheltered nature of these areas also contribute to make them important as nurseries. Man- grove areas thus export protein to coastal areas in the form of aquatic organisms that use the mangrove areas for their early development and then migrate offshore. Well known are the massive migrations of mullets and shrimp from these areas. This is high quality protein that links man- groves directly to other coastal systems like coral reefs , seagrass beds and ultimately to man. A preliminary analysis of published lists of the fish fauna of man- grove areas in Florida (USA) , the Caribbean and Brazil shows that there are more than 275 species of fish belonging to 66 families that are in some way associated with mangrove areas- in these regions . Turner (197 7) found a positive correlation between commercial yields of penaeid shrimp, the area of intertidal vegetation and latitude. The predicted annual yields per area of intertidal vegetation for the latitudinal range of 0-200 range from 39-159 kg/ha. 16 11. CLIMATIC CONSTRAINTS ON DEVELOPMENT Mangroves do not necessarily need rain water, since they extract fresh water from the sea, but the amount of rainfall influences the extent of mangrove development in two ways. First, rainfall determines the rates of soil weathering, erosion and transport, and thus the rate of formation of deltas and other shallow coastal sedimentary features Since these areas are the optimal substrate for mangrove growth, their rate of formation can indirectly determine the extent of coastal man- groves. Second, high temperatures, causing overall high evapotran spiration rates in the tropics, would quickly lead to a salt build-up in the inner parts of mangroves , if it were not for the flushing and leaching of salts by rainwater. According to Macnae (1966, 1968), mangroves develop best in Australia in areas receiving more than 2,500 mm/yr. Below 1 500 mm/yr, salt flats begin to form. Precipitation and evapotranspiratio Rainfall in the Greater Caribbean is very low. Open sea areas receive only 800-1000 mm/yr. However, because of the large amount of solar radiation received at the surface there is a great deal of eva- poration and moisture in the air. When the moisture laden air masses are lifted against the slopes of an island there is condensation and rainfall develops. The windward slopes of high islands are moist for this reason. Convection due to heating of the island mass is another important rain-producing mechanism. Since the land masses gain more 17 heat than the surrounding seas , convection cells and rainstorms develop over the hot interior of islands often in the hot summer afternoons. These rainfall producing mechanisms contribute more rain to the interior of the larger islands than to the coast. Furthermore, the "leading edge" of some islands can be drier than the "trailing edge" and the high islands may have a "rain shadow" zone because of the adiabatic heating of the subsiding air. Low and small islands get very little rain at all. On low islands , and in the "rain shadow" side of the larger islands there are commonly severe water deficits. During the year precipitation is much less than potential evapotranspiration. Under these circumstances, although there may be low areas influenced by salt water, mangroves may be unable to colonize there, due to excessive salt accumulations. The intense radiation turns these low flat areas into natural evaporation ponds. Salt crusts form at the surface and interstitial salinities are much beyond those tolerated by mangroves ( > 9051.). Under these circumstances mangroves develop as a fringe, quite often narrow, in which salinity levels are suitable. Because of the steep salinity gradient inland the landward trees qLdckly become scrubby and poorly developed. Between the swamp and higher ground one finds a hypersaline lagoon (often containing dead or dying trees) and salt flats. Therefore, both rainfall and topography influence the development of basin and fringe forest types. Where precipitation is greater than evapotranspiration basin forests are well developed. The interstitial 18 salinity in these basins is low and they may be dominated by the white mangrove. Where precipitation levels are less than evapotranspiration ( < 1500 mm) basins begin to degrade until they disappear, giving way to the formation of broad salt flats and shallow hypersaline lagoons. In areas where precipitation is less than potential evapotranspiration soil salinity becomes a dominant factor controlling the structural character- istics of the forests . Because of the limited amplitude of the tide in most of the Caribbean, high salt levels may be reached relatively short distances from the edge of the fringe. 12. VULNERABILITY TO STRESSORS A stressor may be defined as a condition that causes an energy drain and a loss of potential energy that could be used to do useful work in a system (Odum 19.67). The sustained operation of a stressor (a chronic stressor) constitutes a constant energy drain and prevents the system from attaining high levels of development. A stressor may also occur periodi- cally, causing transient episodes during which maintenance costs are increased. The resiliency of the system is its ability to respond to and recover from a stressor. Mangrove areas are subjected to natural and man induced stressors both of which can impinge on the system in a chronic or acute mode. For instance, hypersalinity can be a chronic natural stressor in many areas of the Caribbean. Storms and droughts are examples of acute events. Some pollutants can be chronic stressors in polluted areas, or behave as 19 acute stressors during a spill followed by effective cleanup. In general, it is obvious that in a rigorous environment the structural development of the forest will be arrested. In more optimum environments develop- ment will proceed further until the structure is limited by site character- istics such as nutrient availability, water tumover rate and climatic limiting factors such as hurricane recurrence rates. In the following section some natural and man induced stressors are described and their impact on mangrove forests is discussed. The reader is referred to Odum and Johannes' (1975) excellent review for additional information. 12 .1 . Natural Stressors 12.1.1. Tropical cyclones Cyclonic disturbances develop in the north Atlantic, Caribbean, and Gulf of Mexico during the months of June thru November, although they form outside of this "season" in rare instances. These cyclones have high sustained winds , which near their center reach speeds that range from 65 km/hr (40 mph) in a tropical depression to more than 119 km/hr (74 mph) in a hurricane. Mangroves are vulnerable to these disturbances due to their coastal location, their shallow root system (most of which is in the upper 30 cm of the soil) , the poor cohesiveness or load bearing ability of most mangrove soils and their exposure to waves , surge and erosion by strong water flows. Wind speeds greater than 93 km/hr can cause defoliation and winds 20 in excess of 130-160 km/hr will bring down trees. Wadsworth and Englerth (1959) reported that during hurricane Betsy in a black mangrove forest in southern Puerto Rico, 59% of a sample of 62 trees had been overthrown. The maximum reported wind.speed in San Juan, 21 km (13 miles) from the storm's center was 185 km/hr (115 mph). These trees were 26 years old and had diameters (DBH) between 10 cm and 30 cm (4 to 12 in). Black mangroves have very shallow root systems and lack prop roots. The canopy structure also appears to influence this type of forest's sensitivity to wind damage. Canopies of even height without emergents and gaps are more resistant. Mature low density black man- grove "orchard" forests appear to be very susceptible to windthrow. Red mangrove forests , especially in exposed locations , develop an extraordinarily complex and dense root supporting system. This anchorage provides excellent protection from windthrow. Upright (straight'bole) trees are only found inland in sheltered locations. At the fringes , however, wave scour may be a more severe problem than wind. High wind speeds also cause extreme flexing of the stems and separation of the bark from the woody tissue. Violent rubbing between adjacent branches can cause girdling. Even if the tree is not defoliated these branches will die and the trees will appear "burned" after the storm. In an exposed location this type of damage will be more severe in the windward part of the forest. 21 Stoddard (1969) recorded the damages to mangrove areas during hurricane Hattie in British Honduras (Belize). HurTicane Hattie had winds gusting to 322 km/hr (200 mph). In this area there was absolute devas- tation within 1. 6 - 3.2 km (1 --n 2 miles) of the storm's track. The zone of almost complete destruction extended to 32 km (20 miles). In that zone, only small mangrove patches in the leeward portion of the largest islands survived. During storms large amounts of sand and other materials may be dumped into the mangroves. The accumulation of these materials impairs gaseous exchange thru lenticels and pneumatophores and may cause wide- spread mortalities. Usually defoliation ensues within 3-4 weeks. B$ftesen (1909) described an instance where large amounts of sand and gravel were washed into Krausse's lagoon (St. Croix, U.S.V.I.) by the hurricane of 1899. Before the hurricane, the lagoon contained many man- grove islands with open water channels and bare flats. Dense R. mangle forest occurred in the western landward side. After the storm, the vegetation died and the wood was used as fuel for a nearby sugar-mill. Craighead and Gilbert (1962) and Craighead (1964) have similarly de- scribed post-hurricane mortalities due to marl deposition over roots in the Ten Thousand Island area in Florida. Storm waves in Puerto Rico during hurricane David (1979) uprooted large tracts of seagrass beds in various areas. This material was deposited in large quantities ashore. In southwestern Puerto Rico, 22 seagrass accumulations reached 2 m or more high in places, forming a dike in front of the mangrove fringe. Large amounts were carried inside the mangroves. These inordinate accumulations have caused dieoffs in the mangrove because of smoothering and restrictions in tidal exchange, leading to hypersaline conditions. Tabb. and jones.(19.62) report similar occurrences in North Florida Bay as a result of Hurricane Donna. When fringe trees die but remain standing they eventually lose their aerial roots and the associated root community (Tabb et al. 1962). In exposed locations whole cays and fringes may be scoured away by waves. Large boulders and limestone blocks were deposited by waves in some mangrove covered coral islands in southwestern Puerto Rico by Hurricane David. In Cayo Turrumote a boulder rampart 0.5-1 m in height was deposited against the mangrove forest. Recovery is determined by the after storm configuration of the coasts . In places sediment deposition may raise the level of the soil so much that the area cannot be success- fully recolonized by mangroves. In other areas shoals and other structures may have been formed and become available for establishment. Recolonization is slow but ultimately the newly formed banks and shores become stabilized by seagrasses and mangroves, starting the forest development cycle anew. Forest development during the first years is slow and is a function of seed availability. The edges of channels and shorelines quickly develop thickets. The inner parts of the swamps usually develop more slowly since the entry of seedlings is impaired by 23 debris and standing dead trees. -Alexa-ndter (19:6.7.) reported -that extensiIve flooding by salt water (salinity 300Q during Hurricane Betsy caused severe plant kills (scorching) of non-salt tolerant species in the southeastern Everglades. The damage was..increa.sed..by, impounding ciaus.ed by man made dike.s. The -surface waters freshened slowly after the storm, taking about two months to re- vert to normal values. 12.1.2. Tidal waves Tidal waves are not frequent in the Caribbean but these destructive waves are known to have caused widespread damage in the past to low lying coastal areas. In 1946, a tidal wave destroyed a large mangrove forest situated at the head of Bahla de Samand in the Dominican Republic (Sachtler 1973). It is estimated that 4500 ha of a total of 6500 ha were destroyed. The surviving stands were those of black mangroves found in the innermost portions of the swamp. The area recovered from this event rapidly. Presently basal area and density (for stems > 2.5 DBH) in the R. mangle stands are between 17.5-21.5 m2/ha and 463-714 stems/lia , respectively. Mean diameter of the stand for this even aged forest (now 36 years old) is between 19. 6 and 21.9 cm (Cintr6n and Alvarez, unpublished). 12.1.3. Eustatic sea level rise and coastal erosion Sea level is presently rising at the rate of 30 cm/l 00 years. This marine transgression has favored the expansion of mangroves over areas 24 previously occupied by terrestrial plants. There is little doubt that this has induced a regressive movement in the seaward margin of mangroves in many areas. Hoffmeister (1974) reports the erosion of a rock pavement of fossilized roots of black mangroves in Florida. Zieman (1972) has . found circular beds of Thalassia testudinium growing over red mangrove peats. These peats were deposited in hammocks which were submerged by the sea level'rise.-'Extensiv e areas within Card Sound (Florida) show-, severe fringe erosion. The shallow banks in front of the mangrove fringes are sand - or seagrass - veneered red mangrove peat deposits. In Pue rto Rico, peat areas are found on the bottom of shallow embayments overlain by sand. In Bahfa de Samand (D.R.) there is serious erosion of the fringe in considerable segments of the mangrove-lined bayhead shoreline. 12.1.4. Hypersalinity As discussed earlier, hypersalinity is a chronic stressor in most coastal areas of the Caribbean and is one of the dominant factors con- trolling the structural characteristics of these forests. Carter et al. (1973), Burns (1976), Hicks and Burns (1975), and Lugo et al. (1975) have demonstrated that there are increases in respiration and decreases in net productivity with increases in soil salinity. The higher mainte- nance costs are also associated with stunting. As interstitial salinities increase the canopy height decreases (Cintr6n et al. 1978, Fig. 1). The diameter of the trees also decreases as well as basal area , wood volume and complexity index (Mar-ffnez et al. 198 1). 25 The control that salinity exerts over the physiographic character- istics of astand in an arid environment is exemplified by some mangrove islands on the south coast of Puerto Rico (Cintr6n et al. 1975, 1978). The development of a mangrove island over time is shown schematically in figure 2. Initially mangroves colonize shallow banks, expanding laterally over them. The growth of the trees at the outer margins is more vigorous and these trees may attain greater heights . Circulation to the inner parts of the island may be reduced by active growth at the margins. Red mangroves in the core are replaced in time by black mangroves as salinities increase. If soil salinities remain high but stable an island will develop an outer ring of red mangroves and an inner core of well developed black mangroves. Where salinities are too high the core will consist of dwarfed blacks. If circulation is further restricted there will be a dieoff at the core leaving an annular island with a hypersaline lagoon as in step 5 of figure 2. Wave flushing at the windward edge of the island allows the red mangrove fringe to be thicker than on the protected side of the island (Fig. 3). In fact, where there is unimpaired circulation the island may remain in stage I or 2 indefinitely. The maturation process takes place in the islands in more sheltered localities. Fringes may also suffer from a similar aging process. In time extensive areas of the inner swamp die and shallow lagoons and salt flats are formed. These diebacks occur following periods of drought. 26 In dry regions, mangrove areas may be unstable with coverage fluctuating between periods of expansion (usually following storms or a succession of very wet years) and contraction (usually triggered by a succession of dry years). In very dry areas, basins may disappear- altogether leaving only a thin red mangrove fringe backed by shallow bare hypersaline lagoons and salt flats. These areas of dead mangroves are a common feature in dry coast- lines. Bacon (1970) described the "Red Swamp," situated between the Blue and Caroni Rivers in Trinidad. Examination of aerial photographs taken between 1942 and 1966 showed a gradual expansion of the dead areas. Reclamation work in the region may have been responsible for accelerating this dieoff by interfering with water movements. Servant et al. (1978) report the characteristics of one of these hypersaline areas on the islet of Fajou in Guadeloupe. This area is separated by a porous bar from the sea. Seawater penetrates the basin and evaporates , concentrating salts within. Salinities are reduced transiently during episodes of heavy seas when water washes into the basin or when heavy rains leach some of the salts away. This stressful cycle is a common feature of many shallow hypersaline lagoons in the Caribbean area. In most of these and areas the system is delicately poised and man's intervention by reducing water flows or impounding areas by structures such as causeways and roads often exarcebates 'A these naturally occurring stressful conditions causing mortalities too. 27 12.2. Man Induced Stressors 12.2. 1. Channelization, diversion of fresh water Channelization and fresh water diversion schemes are extremely damaging. Mangroves are open systems and require continuous nutrient inputs to maintain their high rates of productivity and other ecosystem processes. Furthermore, in and areas reduction of fresh water input quickly results in the onset of hypersaline conditions and mangrove dieoff. 12.2.2. -Impoundment Impoundment is another stressor that leads to rapid deterioration and death of mangrove areas. Diking cuts off mangroves from nutrient flows' it may raise water levels or lengthen the hydroperiod, causing the lenticels and pneumatophores to-become covered with water. This impairs or stops gas exchange. In other instances lowering water levels or reducing flows causes salinity to increase rapidly as salt water eva pora te s . In 1965, the Department of Agriculture of Puerto Rico built a dike impounding a 177 ha mangrove stand and flooding it to a I m depth. The purpose was to artificially create a habitat for wading birds. A massive dieoff followed immediately. The area had contained an extensive and well developed black mangrove forest (DBH^- 10 cm). Only those trees on higher ground survived and then did so by producing extremely long pneumatophores (36.1 cm � 0.5 as against 10-15 cm in normally flooded 28 areas) . There has been very limited natural restoration of the area. The dikes restrict tidal flushing so that during the dry season the impounded area dries up. The loss of the canopy exposes the impounded water and soil to the sun and extreme overheating during the dry season. Dissolved oxygen in the heated surface water (temperature > 30tO C). drops below. 0. 5 mg/L. White mangroves have recolonized some areas by becoming estab- lished over the stumps of fallen trees., The water depth reached during the wet season appears to limit the areas that can be colonized by man- groves. Impoundment can also occur when roads are built through mangrove basins if.care is not taken to preserve water flows. Patterson-Zucca (1978) has described the impact of road building on a mangrove swamp. M In St. Thomas I construction of a road near Compass Point isolated and killed a small mangrove area. Hypersalinity may have been the cause of that dieoff. 12.2.3. Sedimentation Mangroves are adapted to high sedimentation environments, but sudden deposition of large quantities of sediments can cause mortality. Under natural conditions , excessive sedimentation occurs as a result of catastrophic penomena like storm generated waves or floods. Man, however, is often the cause of severe sedimentation problems in some mangrove areas. Cintr6n and Pool (1976) reported that sand extraction 29 from a coastal dune for airport construction reduced the dune height from 12 m to only 3m. During 1967, storm waves overwashed the residual dune, carrying large amounts of sand into a mangrove forest. Sand deposition varied from more than one meter to a thin sand veneer more. than. 260 m, inland.. All*the mangroves, were killed where sand deposits were higher than 30 cm, and some trees died where the sedi- ment depth was between 20 and 3'0 cm. The area covered by the sand wedge has been colonized by Australian. pine (Casuarina equisetifolia). Kolehmainen (cited by Odum and Johannes , 1975) noted an area in Puerto Rico where fibrous waste from a sugar mill escaped from settling ponds and killed most of the trees in a black mangrove QL. germinans) stand. Deposition of dredge spoils into mangrove areas will also cause large scale mangrove mortalities. During the late 1960's , dredged material was discharged into the Punta Picda penninsula on the north coast of Puerto Rico., causing the total d.estruction.of a large. mangrove tract. This area too has been extensively colonized by Australian pine. Deforestation and loss of soil can increase the rate of sedimenta- tion in low lying swamps, causing shallow lagoons to become salt flats and killing inner swamp trees. 12.2.4. Thermal pollution In shallow stagnant areas water temperatures may reach more than 430 C (1100 F) . These areas are not reseeded since temperatures may 30 be limiting (Craighead 1964). McMillan (1971) reported that temperatures of, 39-14-00, C' for 418'.hlours.' ca-us, ed'd [email protected] o f-I rooted but s1te' mless A . germinan s seedlings. The cooling water plumes from electric generating plants often approach.thi -temperature. In Puerto Rico, Banus and Kolehmainen. (197.6) ha ve suggested that temperatures above 380 C (1000 F) define the begin- ning of deterioration of mangrove trees. These stressed trees have small leaves (Lugo and Cintr6n, 1975), are partially defoliated (only terminal leaves remain) , chlorotic and produce dwarfed seedlings. The mangrove root community is much more sensitive to high temperatures than the mangrove trees (Kolehmainen et al. 1974). The species composition and biomass of mangrove root communities was unaffected by temperatures below 340 C (930 F). Between Wand 350 C (93 and 950 F) the number of species decreased abruptly, and above 350 C (950 F) the number of species was inversely related to the water temperature. At higher temperatures , 37.5-39.70.C (99.5-103.50 F) , blue green algae.became common, forming floating mats in the water surface. 12.2.5. Oil Mangroves are extremely sensitive to oil pollution because of fouling of the gas exchange surfaces. Heavy coating of the intertidal root region or pneumatophores invariably causes death of the trees. In addition to acting as a mechanical barrier oil contains soluble toxic fractions. These compounds can be toxic to the roots and to the microbial populations in the soil. 31 The initial response of mangroves exposed to severe oil fouling appears to be defoliation. Defoliation may be partial or total, depending on the amount of oil remaining in the roots and substrate. Following the Peck Slip oil spill in eastern Puerto Rico, the heavily impacted areas lost 50% of the canopy in 43 days and 90% after 85 days (Cintr6n et al. 1981). Total loss of the canopy was irreversible in the oil stressed red mangroves. In the marginal areas where the trees were exposed to sublethal amounts of oil defoliation was followed by production of smaller, often deformed, new leaves. Lugo et al. (1981) have suggested that different forest types exhibit different susceptibility to oil pollution. For instance , riverine forests appear to be least vulnerable to oil pollution since the surface fresh- water flows move the oil slicks away. Oil spilled in the ocean has little chance of entering the river mouth since salt water enters as a bottom flow. The greatest vulnerability for this forest type would occur during the dry season when surface flows are reduced or if the spill occurs up river or inside the estuary. In exposed locations, sand bars formed in front of river mouths can hinder oil penetration. Basin mangroves are most susceptible to stressors that originate inland and therefore are less vulnerable to seaborne oil. Often (but not always) basins are isolated from fringes by berm. Basins are most vulnerable during periods of spring tides. They can be severely impacted by spills that originate from inland facilities and pipelines. Since oil 32 would be retained for a long time in a basin its effects would be devas- ta ting - Fringe and overwash forests are the most vulnerable to seaborne oil. Oil enters the fringe and accumulates inside. In the outer edge of the fringe water motion assists in cleansing the root surfaces. For this reason, there may not be any-defoliation of the trees in the outer edge and complete canopy loss inside. In very sheltered locations, however, defoliation may be total. Presently, there are no practical means to remove oil from man- grove areas . For this reason, it is imperative to prevent the entry of oil by using booms and sorbent barriers. Oil tends to penetrate into the porous mangrove sediments'and persist for very long time periods. Residual amounts of oil are still found in Bahra Sucia in southwestern Puerto Rico after a spill that occurred in 1973. In areas in which there are high rates of water exchange oil is leached out and seedlings are brought in so that recuperation from an acute event occurs quickly. Where large residual amounts of oil persist recovery may be considerably delayed. In fact, residual amounts of oil may impede the reestablish- ment of a well developed stand. The "successful" establishment of red mangrove seedlings in an area impacted by oil does not mean that the site is on its way to recu- peration. Red mangrove seedlings are very tolerant to stressors but this tolerance decreases as the plant develops and requires more from the 33 external environment rather than from its ample storages, This indepen- dence is prolonged by the slow growth rate of the seedlings (0. 4 - 0. 5 cm/mo during the first months). This, and the continual replacement of dead seedlings by new arrivals gives the false impression that natural regeneration is occurring. It seems however, that when significants amounts of oil remain in the sediment, seedlings dieoff as their initial high tolerance decreases. The development of saplings into mature trees may be dependent upon the rage at which oil is leached or degrad4d. 12.2.6. Mining There are no known mining activities currently occurring in man- grove areas of the Caribbean. The energy crisis has pressed considera- tion of the use of peats as energy sources and mining of these peats has been contemplated in the Negril's Great Morass in Jamaica. In Puerto Rico, sand was mined from mangrove lined coastal lagoons during the 1960's. This activity created pits 18 m deep in places in lagoons whose original depth was only 1-2 m. These pits trap saline water and are depositional basins for organic sediments with high oxygen demands. As a result, the pits are persistently anoxic below 2 m, the BOD5 in the bottom waters often exceeds 200 mg/L and NH4 as (N) may be in excess of 15 mg/L (Ellis 1976). 13. RECOVERY Natural ecosystems have growth strategies and adaptations that allow them to recover from periodic natural perturbations . Because of 34 this inherent resiliency ecosystems will restore themselves sponta neou-sly once the disturbance has subsided. Assuming that there are no residual effects left by the stressor(s) an ecosystem will normally revert to a state very similar to its pre-stressed condition. Under the influence *of residua:1 stressors and/or an. increase'.d. necurrence rate of.acute events the system will only achieve a simpler Ieve I of organization (Odum 1981) In general, then, human intervention in the restoration process could be limited'to removing the'stressor that is causing the degradation and allowing the system to restore itself. It is wasteful and useless to attempt to restore areas artificially if the stressor has not been removed or residual amounts are left. In the case of mangroves, the rate of recovery in a benign environ- ment is a function of the size and proximity to seed sources. The conservation of ample seed stocks insures quick and natural regenera- tion with minimal human intervention. In some areas , it may be desirable to accelerate the recovery of a stand by preparing the terrain and insuring an even distribution of seedlings by planting. Pulver (1976) gives some preliminary guidelines for the transplant of saplings (0.5-1.5 m in height). Planting saplings, however, is more difficult and costly than planting seedlings and the saplings must be removed from natural stands. The following points should be considered before artificial restoration is attempted: 35 Select candidate sites. carefully.. If the area has contained mangroves before, determine the cause of loss and make sure the stressor has been removed. Naturally, "blank" areas may be hypersaline or too elevated for successful .-.establishment. Because of the ease of handling and planting, red mangroves are one.of the -mos.t. suitable species for riestoration'.projects but they may not always be appropriate. The selection of the species to plant should be made on the basis of the dominant species at nearby locations having similar eleva- tion, hydroperiods and exposure. Soil elevation should be low enough that the area is frequently flooded by tidal water, and there is adequate circulation. Stagnant areas tend to overheat. Measure interstitial (soil) salinities. Areas with inter- stitial salinities above 55%, are not suitable for restoration by red mangroves. Areas must be sheltered from wave action and current scour. Remove dead standing wood and clean-up the area. Floating or falling debris will uproot and damage planted seedlings. 36 Control the spacing of seedlings, Dense plantings result in stagnation' (slow growth) due to excessive c.ompetition. For Rhizophora sp. the recommended spacing for seedlings is 0.6-1.2 m (Watson 1928). Recently, fallen seeds-may be collected from nearby man- grove areas or they may be collected from trees. Use only ripe seeds. For red mangrove, use those. seeds in which the abscission layer has developed (these are easily detached from the parent tree). Select healthy seeds and discard malformed or damaged propagules. Maintain the collected material wet and avoid exposing it to overheating during transportation and before planting. Seeds can be carried in an inexpensive 'foam icebox or a wet burlap sack. Red mangrove seedlings should not be inserted too deeply in the..substrate.. The seed should be planted deep enough so that it will not fall over (Watson 1928). For a 20-30 cm seedlings the planting depth should be 4-7 cm. Since initial growth rates and mortality of red mangrove seedlings are very low it is impossible to judge the success of a restoration h's observations . The restored area pro-ject on the basis of a few mont should be checked annually to replace dead saplings and/or remove unwanted new arrivals. 37 14. -CONCLUSION: - CONSERVATI.ON NEEDS Island coastal marine ecosystems are in jeopardy in many areas of the Caribbean, due to high populations, mounting pressures to develop, a limited land base, and inadequate impact assessment procedures. In..the smaller. i.slands inland-and.coa$tal ecosystems are intimately- linked. Inland activities like deforestation, agriculture on steep slopes , raising of domestic animals , road building and many others can increase sediment levels in estuarine and coastal waters , contributing to the degradation of coastal ecosystems. Protection of the marine resources depends on developing land use practices that will not impair the productivity of mangroves, seagrass beds and coral reefs . Society derives direct benefits from the conservation of these coastal ecosystems. They are part of the resource base upon which islands depend. There are very practical reasons for their conservation, including the products they yield (fisheries) and their role in protecting the coasts from storm damage, as well as their more intangible values. Tourism, an important source of income, can be developed to take advantage of their uniqueness and great beauty. Natural reserves or parks can be established to protect especially important areas; these attract local. as well as international tourism and also stimulate scientific research, all of which benefit the local economy. They are valuable educational assets. On a more modest scale small projects can be developed to take 38 advantage of areas of particular s-cenic beauty.. This kind of project, when designed for mangroves , 'need's to take into account the fact that mangrove areas are naturally prone to flooding; structures built in these areas are susceptible to recurrent damage by flood waters and storms unless they are'constructed with flooding.in mind. Because of -the danger of storms, no permanent population centers should be encouraged to develop in mangroves , 'since the occupants would alway's be at risk. In summary, mangroves are among the most productive coastal ecosystems known to science. In addition to their aesthetic and recreational values, they form an important part of the economic resource base of Caribbean islands because of their intimate ties to coastal fisheries, seagrass beds and coral reefs. In many areas they still evoke negative reactions , because of a lack of understanding of their importance. 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Watson, 1. G. 1928. Mangrove forests of the Malay Peninsula. Malayan Forest. Rec. 6:1-275. Zieman, J. C. 1972. Origin of circular beds of Thalassia (Spermato- phyta: Hydrocharitaceae) in south Biscayne Bay, Florida , and their relationship to mangrove hammocks. Bull. Marine Sci. Gulf Caribb. 22(3):559-574. CT orcranic matter/m2.dav Gross Net Primary Total 24 hr Primary Forest Type Productivity Respiration Productivity Riverine 24.0 11.4 120 6 Basins 18.0 12.4 5.6 Fringes 13.2' 11.3 8.8 Hammocks 3.8 1.2 2.6 Dwarf 2.8 4.0 -- Table 1. Summary of primary productivity and respiration data for different mangrove forest types. Based on Lugo and Snedaker (1974) review. 0 SAN ILDEFONSO Y= -0. 20 X + 16.58 0 PUERTO DEL MANGLAR R2 0.72 (WET) 13 PUERTO DEL MANGLAR (DRY) .,&MAR NEGRO e ISLAND 1. BAHIA MONTALVA 0 ISLAND 2 10 BAHIA MONTALVA MONA ISLAND C30 0 ui 5 0 00 A 0 30 40 50 60 70 80 SOIL SALINITY (0/00) mangroves Fig. 1 . Relationship between tree height and soil salinity in of arid- coastlines of Puerto--Rico and adjacent islands (Cintr6n et al., 1978). I- INITIAL COLONIZATION OF -OFF SHORE BANK th-dut di rh 2- LATERAL GROWTH OVER BANK 3- DEATH OF RHIZOPHORA AT THE CORE'AN D'@ COLONIZATION BY AVICENNIA I R 3a-ALTEr"%"NATE STAGE AVICENNIA GROWTH STUNTED. STUNTED OR DEAD RHIZOPHORA AT CORE. .4- ISLAND WITH STUNTED AVICENNIA CORE. 5- MATURE ISLAND WITH HYPERSALINE LAGOON. Fig. 2. Conceptual scheme of mangrove succession for mangrove islands in and coastlines (Cintr6n et al. 1978). 77- "Imp in THICKNESS -OF MANGROVE FRINGE (METERS) o U) (A ,-, En 0 0 It Ul r1ri iff z > rn n o rt 0 (A rn a (D CD r+ 00 rn NOAA COASTAL SERVICES CTR LIBRARY I 1 3 6668 14110892 0