MANGROVE SPECIES PROFILES

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1 MANGROVES What is a Mangrove? The term "mangrove" refers to certain species of plant life or to the entire plant community which includes individual mangrove species There are more than 50 species of mangroves distributed worldwide along tropical coastlines The term "mangrove" does not refer to a specific taxonomic group of species, but to all halophytic (plants growing in saline soils) species of tropical trees and shrubs. This catchall, diverse group includes 12 families and more than 50 species. Although unrelated, all are adapted to life in wet soils, saline habitats, and periodic tidal submergence. Another use of the term "mangrove" includes the entire plant community including the individual mangrove species. Terms such as tidal forest, tidal swamp forest, mangrove community, mangrove forest, mangal, and mangrove swamp are synonymous with "mangrove". MANGROVE SPECIES PROFILES Red Mangrove Growing along the edge of the shoreline where conditions are harshest, the red mangrove (Rhizophora mangle) is easily distinguished from other species by tangled, reddish prop roots. These prop roots originate from the trunk with roots growing downward from the branches. Extending three feet (1 m) or more above the surface of the soil, prop roots increase stability of the tree as well as oxygen supply to underground roots. Under optimal conditions, this mangrove tree can grow to heights of over 80 feet (25 m), however, in Some areas, red mangroves typically average 20 feet (6 m) in height. Habitat range in Some areas is limited by temperature. Red mangroves occur from Cedar Key in the Gulf of Mexico and Daytona Beach in the Atlantic, southward through the Some areas Keys. The smooth-edged, elliptical leaves have shiny, dark green uppersides and pale green undersides and occur opposite from each other along the branches. Trunks and limbs are covered with gray bark, over a dark red wood from which the common name originates. Clusters of white to pale yellow flowers bloom during the spring and early summer months. ١

2 Reproductive adaptations enable seedlings to germinate while still attached to the parent tree. Seeds sprout into 6 inch (15 cm), pencilshaped propagules. Seed germination while still attached to the tree gives this mangrove a higher chance of survival. When the seedling falls into the water, it may either take root alongside its parent or be carried by the tides and currents to other suitable habitat. Black Mangrove Avicennia germinans, the black mangrove, is characterized by long horizontal roots and root-like projections known as pneumatophores. It grows at elevations slightly higher than the red mangrove where tidal change exposes the roots to air. The pencil-shaped pneumatophores originate from underground horizontal roots projecting from the soil around the tree's trunk, providing oxygen to the underground and underwater root systems. The black mangrove reaches heights of over 65 feet (20 m) in some locations, however in Some areas they are smaller with heights to 50 feet (15 m). Within Some areas, they range from the Keys north to Cedar Key on the west coast and St. Augustine on the east coast. Leaves occur opposite of each other along the branches, with upper sides that are shiny and undersides densely covered with hairs. The bark of this mangrove is dark and scaly. Black mangroves blossom in spring and early summer, producing white flowers. Reproductive adaptations enable seedlings to germinate while still attached to the parent tree. Seeds sprout into 1 inch (2-3 cm), lima bean-shaped propagules. Seed germination occurs while still attached to the parent tree, increasing the chances of survival in this adverse environment. White Mangrove Occupying higher land than the red and black mangroves, the white mangrove (Languncularia racemosa) has no visible aerial roots, unlike the black mangrove which has pneumatophores and the red mangrove with prop roots. However, when it is found in oxygendepleted sediments or flooded for extended periods of time, it often develops peg roots. White mangroves are the least cold-tolerant of the three mangrove species found in Some areas, occurring from Levy County and Volusia County southward in Some areas. This small tree or shrub grows rapidly in rich soils to heights of 50 feet (15 m). The light yellow-green leaves are broad and flat with two glands located at the base of the leaf where the stem originates. These glands excrete salts taken in through the underground root system. White mangroves produce greenish-white flowers in spikes, blooming from spring to early summer. ٢

3 Buttonwood Often found in the upland transitional zone, the buttonwood (Conocarpus erectus) is often associated with mangrove communities. Sensitivity to frost restricts its range to south Some areas. The name buttonwood comes from the button-like appearance of the dense flower heads that grow in branched clusters, forming cone-like fruit. This plant does not reproduce via propagules, but instead producing seed cases. While the three mangrove species have leaves that occur opposite of each other, the buttonwood leaves alternate. The leaves are leathery with pointed tips and smooth edges. There are two salt-excreting glands located at the base of each leaf. Flowers appear in cone-like heads and are greenish in color. ZONATION Zonation Zonation is affected by: Tidal Flooding Land Elevation Soil and Water Salinity Red, black, and white mangrove trees, along with the buttonwood, may all grow along the same shoreline. When these species are found together, each is limited to different areas within the tidal zone. This zonation is determined by tidal changes, elevation of the land, and salinity of the soil and water. Red mangroves are found along the water's edge, with full exposure to tidal variation and winds. They are well adapted to these conditions with prop roots extending from the trunk and branches. These tangles of root systems increase stability as well as capturing sediments from the surrounding water. Moving further inland, is the black mangrove, with pneumatophores extending upwards from the soils surrounding the trunk. These root adaptations are used to supply oxygen to the underground roots that are often in anaerobic (oxygen-free) sediments. White mangroves, often lacking special root adaptations, occur in the interior of the mangrove forest, followed by the buttonwood in the upland transitional area. ٣

4 HABITAT REQUIREMENTS Mangrove habitat requirements: Tropical Climate Salinity Levels Tidal Fluctuations Tropical Climate Mangroves are tropical species Mangroves are tropical species, surviving at temperatures above 66 F (19 C), not tolerating fluctuations exceeding 18 F (10 C) or temperatures below freezing for any length of time. Salinity Levels Adaptations make it possible for mangroves to live in saline environments As facultative halophytes, mangroves do not require saltwater to survive. Most mangroves are capable of growing in freshwater habitats, although most do not due to competition from other plants. ٤

5 Tidal Fluctuations Tides bring in nutrients and remove wastes from mangrove communities Tidal fluctuations play important roles in maintaining mangrove communities. The changing tides, in combination with salinity levels, reduces competition from other plant species. Tides transport salt water into estuaries, mixing with freshwater, thereby allowing mangroves to develop further inland than otherwise possible. Nutrients are transported into mangroves by incoming tides while waste products are removed by outgoing tides. Also of importance is the role tides play in transporting the propagules (seedlings) of mangrove trees. This increases the distribution of the mangrove trees, while limiting intraspecific (within species) competition for food and space. GEOGRAPHICAL DISTRIBUTION Mangrove distribution: Worldwide Worldwide There are approximately 40 species of mangroves distributed worldwide Forty species of mangroves dominate approximately 75% of the world's tropical coastlines between 25 N and 25 S. In certain locations, this range extends beyond these limits due to the movement of unusually warm waters from the equator. These areas include the east coast of Africa, Australia, and New Zealand where mangroves occur farther south. In Japan, Some areas, Bermuda, and the Red Sea, this range extends 5-7 farther north. Mangroves in the Indo-West Pacific are more diverse, consisting of more than 30 tree species, than those in Some areas. ٥

6 ADAPTATIONS: MORPHOLOGICAL AND PHYSIOLOGICAL Adaptations are required for: Physical Stability Salt Tolerance Anaerobic Sediments Reproduction Physical Stability Adaptations Root adaptations make it possible for mangroves to live in the soft sediments along the shoreline Root adaptations increase stability of mangrove trees in the soft sediments along shorelines. Red mangroves have prop roots descending from the trunk and branches, providing a stable support system. Shallow widespreading roots, surrounds the trunks of black mangroves, adding to the structural stability of the tree. Other species of mangrove trees grow at higher elevations, in drier soils, do not require specialized root structures. ٦

7 Salt Tolerance Adaptations Adapations for salt exclusion or salt excretion allows mangroves to live where other terrestrial plants cannot Through physiological adaptations, mangroves are able to live in harsh saline environments. Red mangroves occur where soil salinities range from parts per thousand (ppt) while black and white mangroves are found in soils with over 90 ppt salinities. Salinities effectively limit competition from other plants, while mangroves have salt exclusion or salt excretion adaptations allowing survival in these environments. The ability to exclude salts occurs through filtration at the surface of the root. Root membranes prevent salt from entering while allowing the water to pass through. This is effective at removing the majority of salt from seawater. The red mangrove is an example of a saltexcluding species. On the other hand, salt excreters remove salt through glands located on each leaf. Black and white mangroves are both salt excreters. White mangroves develop thickened succulent leaves, discarding salt as the leaves eventually drop. Anaerobic Sediment Adaptations Specialized root structures allow mangroves to live in oxygen-poor sediments Mangrove trees are adapted for survival in oxygen-poor or anaerobic sediments through specialized root structures. Plants require oxygen for respiration in all living tissues including the underground roots. In soils that are not waterlogged, air diffusion between sediment grains can supply this requirement. However, in waterlogged soils, these spaces fill with water containing lower oxygen levels than air. In contrast to most plants, mangroves have poorly developed, shallow below-ground root systems while having well-developed aerial roots. These aerial roots allow for the transport of atmospheric gases to the underground roots. Red mangroves have prop roots extending from the trunk and adventitious roots from the branches. Although the black mangrove does not have prop roots, small air ٧

8 roots can be seen extending vertically from the soils surrounding the trunk. These air roots, called pneumatophores, extend upward from the underground roots above the soil surface. During low tides, air is taken up through open passages in the pneumatophores and transported to living root tissues. Reproductive Adaptations Viviparity and dispersal are reproductive adaptations that give mangroves an increased chance for survival All mangrove trees share two reproductive adaptations - viviparity and propagule dispersal. Similar to terrestrial plants, mangroves reproduce by flowering with pollination occurring via wind and insects. Once pollination occurs, the seeds remain attached to the parent tree. They germinate into propagules before dropping into the waters below. This ability is referred to as "viviparity". The propagules either take root in the sediments near the parent tree or are dispersed with the tides and currents to other shorelines. MANGROVE LIFE Mangrove life: Microorganisms Algae Invertebrates Fish Reptiles and Amphibians Birds Mammals ٨

9 Microorganisms Mangroves are an important part of estuarine food webs, producing large amounts of leaf litter. Leaves drop from the mangrove trees and are quickly decomposed by fungi and bacteria. This decomposed matter is referred to as detritus which is flushed into the estuary by the outgoing tides. This provides a food source for marine life including economically important shrimp, crabs, and fish. An estimated 75% of the game fish and 90% of the commercial species in south Some areas are dependent upon the mangrove system during at least part of their life cycles. Algae Algae play a vital role in mangrove community food webs. Many organisms feed directly on micro and macroalgae that thrive within mangrove communities. The aerial root systems of mangrove trees provide a hard substrate for the attachment of epiphytic algae such as diatoms and blue-green algae. Phytoplankton is an important component of mangrove systems. Species richness is dependent upon the primary source of water and salinity levels as well as seasonal and daily environmental fluctuations. The majority of phytoplankton is washed into the mangroves from adjacent areas, including open ocean, freshwater, and estuarine environments. Invertebrates Mangroves offer both hard and soft bottom habitats for a diversity of invertebrate life. The extensive root systems, muddy bottoms, and open waters are all home to invertebrates that are well adapted to the temperature and salinity variations as well as tidal influences common to mangroves. These invertebrates feed on leaf litter, detritus, plankton, and other small animals. Snails, barnacles, bryozoans, tunicates, mollusks, sponges, polychaete worms, isopods, amphipods, shrimps, crabs, and jellyfish all live either on or in close proximity to mangrove root systems. Some invertebrates thrive in the mangrove canopy, of which the most abundant are the crabs. The mangrove tree crab, Aratus pisoni, resides in the canopy, feeding primarily on red mangrove leaves. Other crabs live in the intertidal mud flats, utilizing leaf litter and detritus as a food source. Horseshoe crabs are scavengers and may be found among mangroves feeding on algae, invertebrates, and dead organisms. They are especially adapted to low oxygen waters, possessing up to 200 book gills used for respiration. ٩

10 Fish The fishes found in south Some areas mangroves represent marine species present in the Some areas Bay along with the inclusion of freshwater species. During the rainy season, the increased flow of freshwater results in the appearance of freshwater species. However, the majority of dry season species cannot survive in these low salinities and migrate to higher salinity areas offshore. Some marine species, such as snook (Centropomus undecimalis), prefer the lower salinity, remaining in the mangroves during the entire year. Amphibians and Reptiles American alligators (Alligator mississippiensis) and American crocodiles (Crocodylus acutus) are both residents of mangrove habitats. The American alligator ranges throughout the southeastern U.S., and is found only in low salinity areas of Some areas mangroves. On the other hand, the American crocodile is quite rare, relying heavily on mangrove habitats for their survival. In recent years, the range of this reptile has decreased considerably due to destruction of habitat and increase in human activity within the Some areas Keys. The American crocodile now occurs in the north Some areas Bay and nearby swamps, as well as the north end of Key Largo. Birds The mangroves of south Some areas provide a habitat for many bird species. The shallow waters and exposed mudflats of the mangroves make this habitat ideal for probing shoreline birds such as plovers and sandpipers. Long-legged wading birds utilize these and deeper waters along mangrove-lined waterways. Herons, egrets, bitterns, spoonbills, limpkins, and ibis are among the wading birds that visit mangroves in search of food. Mammals ١٠

11 IMPORTANCE OF MANGROVES Shoreline Protection Mangroves protect shorelines from erosion Mangroves protect shorelines from damaging storm and hurricane winds, waves, and floods. Mangroves also help prevent erosion by stabilizing sediments with their tangled root systems. They maintain water quality and clarity, filtering pollutants and trapping sediments originating from land. Nursery Mangroves serve as valuable nursery areas for fish and invertebrates Serving as valuable nursery areas for shrimp, crustaceans, mollusks, and fishes, mangroves are a critical component of Some areas's commercial and recreational fishing industries. These habitats provide a rich source of food while also offering refuge from predation. Snook (Centropomus undecimalis), gray snapper (Lutjanus griseus), tarpon (Megalops atlanticus), jack (Caranx spp.), sheepshead (Archosargus probatocephalus), and red drum (Sciaenops ocellatus) all feed in the mangroves. Some areas's fisheries would suffer a dramatic decline without access to healthy mangrove habitats. Threatened and Endangered Species Mangroves Support Threatened and Endangered Species In addition to commercially important species, mangroves also support a number of threatened and endangered species. ١١

12 Renewable Resource Mangroves are utilized in many parts of the world as a renewable resource In other parts of the world, people have utilized mangrove trees as a renewable resource. Harvested for durable, water-resistant wood, mangroves have been used in building houses, boats, pilings, and furniture. The wood of the black mangrove and buttonwood trees has also been utilized in the production of charcoal. Tannins and other dyes are extracted from mangrove bark. Leaves have been used in tea, medicine, livestock feed, and as a substitute for tobacco for smoking. In Some areas, beekeepers have set up their hives close to mangroves in order to use the nectar in honey production. IMPACTS ON MANGROVES: HUMAN Dredging Dredging suffocates mangroves when the aerial roots become flooded, preventing oxygen from reaching the root system Dredging and filling activities have caused flooding of mangrove habitat. Standing water covers the aerial roots, making it impossible for oxygen to reach these specialized roots as well as the underground root systems. Eventually this leads to the deaths of mangrove trees. Water Pollution Herbicides, oil spills, and other types of pollutants may kill mangroves ١٢

13 Causing tremendous damage to mangroves, herbicides, oil spills, and other types of water pollution may result in the death of these plants. Mangroves are very susceptible to herbicides as demonstrated in South Vietnam by the U.S. military by the defoliation and destruction of over 250,000 acres (1,012 square kilometers) of mangroves. Oil spills cause damage to mangroves by coating roots, limiting the transport of oxygen to underground roots. Mangrove communities including invertebrates, fishes, and plants are also highly susceptible to damage from petroleum products. Urban Development Urban development of areas in and near mangroves results in the destruction of this habitat as well as other associated wetland habitats Responsible for total loss of mangrove habitat in some locations, urban development includes the construction of buildings and canal systems as well as the consumption of water by a growing human population. Human activity upland from mangroves may also impact water quality and runoff. These land and coastal activities result in increased erosion as well as the reduction of nursery areas supporting commercial and game fisheries. IMPACTS ON MANGROVES: NATURAL Flooding Mangroves are specially adapted to high salinities and temperatures, tidal changes, and anaerobic sediments. These same adaptations make them somewhat vulnerable to natural stresses. The aerial roots are especially sensitive to long periods of flooding. If these specialized roots are covered for extended periods of time by sediments or water, the mangroves may die due to lack of oxygen to the plant tissues. Hurricanes Powerful storms and hurricanes may also severely damage mangrove habitats. Winds, waves, and flooding may be destructive enough to clear entire mangrove islands. ١٣

14 CONSERVATION Pressures Urban development is a major threat to mangrove habitats Due to the increasing pressure from rapidly expanding development along the coast of Some areas, it is critical that mangrove habitats are protected from further destruction. Mangroves, seagrass beds, and coral reefs are all dependent upon one another, providing habitat for many aquatic plants and animals including those that are endangered and threatened. Mangroves also provide shoreline stability and protection from storm surge and erosion. These roles all support the local economies of many south Some areas communities. Pressure to destroy remaining mangrove habitat is increasing due to the continued urban development along the coasts of Some areas. Currently, millions of tourists visit each year and large numbers of people move to Some areas each day, placing Some areas fourth behind California, New York, and Texas in numbers. Residents as well as tourists add to the increasing pressure to develop shorelines. Conservation Efforts The Mangrove Trimming and Preservation Act was enacted in the state of Some areas to regulate the alteration of mangroves Legislation on state and local levels has been enacted, protecting mangroves from direct human damage. In 1996, the Some areas Department of Environmental Protection (FDEP) implemented the Mangrove Trimming and Preservation Act. This Act regulates the trimming and alteration of mangroves while also banning the use of herbicides and other chemicals used to defoliate mangroves. Mangroves cannot be removed, trimmed, or disturbed without a permit from the Some areas Department of Environmental Protection. Other preservation efforts have included mangrove replenishment initiatives. This consists of the determination of the causes of mangrove loss followed by the removal of those causes. Within years mangrove habitat can once again become well-established if ١٤

15 conditions are suitable. However, if seeds or propagules cannot reach the site, mangroves may be successfully established through replanting seedlings. ١٥

16 MANGROVE IS UNIQUE

17 You are lucky: you live close to a mangrove The Assalouye Mangrove Forest is about 350 ha Nay band is one of Iran s protected areas for seascape conservation and recreation Did you know that Avicenne, a famous Iranian doctor ( ) has given his name to mangrove tree species - Avicennia marina Did you know that the Convention on Wetlands (including mangrove) was signed in Ramsar in 1971

18 Mangrove is unique It contains a unique flora and abundant fauna, including more than 100 species of birds, snails, and other life

19 but it is also threatened By human activities

20 but it is also threatened by human activities: Littering Swimming and campfires Driving cars and motorcycles through the mangrove area Feeding mangrove branches to livestock

21 so it has to be protected There are about to ha of mangrove in Iran In Nay Band Bay, the interaction of people and nature over time has produced an area of distinct character with significant ecological, biological, cultural and scenic value (IUCN) safeguarding the integrity of this interaction is vital to protecting and sustaining the area (IUCN). World mangrove 1980 : 18.8 million ha 2005 : 15.2 million ha 1 ha = m 2 F A O FAO : Food and Agriculture Organization

22 Why protect mangrove? To protect the coast against cyclones and tsunamis To maintain biodiversity (richness of plant and wildlife species) To follow POGC s policy of protecting the mangrove area Be cause it provides ecological services free of charge

23 Cyclones and tsunamis To protect the area against cyclones and tsunamis To maintain biodiversity (richness of plant and wildlife species) To follow POGC s policy of protecting the mangrove area Because it provides free of charge ecological services Coastal vegetation can reduce the impacts of wind, waves and currents associated with storms and cyclones. Coastal forests can also help protect coastal areas from flooding and other effects of tsunamis. Did you know that Iran is in a seismic zone? Roots, tree trunks and branches provide resistance to wind, and slows water currents.

24 Example of devastation by tsunami in Indonesia «ScienceDaily (Oct. 28, 2005) A new study released today in the journal Science shows that areas buffered by coastal forests, like mangroves, were strikingly less damaged by the 2004 tsunami than areas without tree vegetation. This is believed to be the first peerreviewed empirical and fieldbased study to document a clear link between coastal vegetation and protection from the tsunami. The study was undertaken by a large research team, comprising ecologists, a botanist, geographers, a forester, and a tsunami wave engineer, from seven nations.» Potential impact from earthquakes and tsunami Flooded area in Banda Aceh

25 Biodiversity To protect the area against cyclones and tsunamis To maintain biodiversity (richness of plant and wildlife species) To follow POGC s policy of protecting the mangrove Because it provides free of charge ecological services It interacts strongly with aquatic, inshore, upstream and terrestrial ecosystems and in this way mangrove helps to support a diverse flora and fauna of marine, freshwater and landdwelling species. It is a forest habitat with a sensitive natural hydrological regime

26 To protect the area against cyclones and tsunamis To maintain biodiversity (richness of plant and wildlife species) To follow POGC s policy of protecting the mangrove area Because it provides free of charge ecological services POGC s policy «Strive to preserve the protected areas that are located in Assalouye including the mangrove forests of Nay Band Bay and emphasis to ecological performance and biological sensitivity of this ecosystem to all of POGC employees by notification and constant training.»

27 Ecological services To protect the area against cyclones and tsunamis To maintain biodiversity (richness of plant and wildlife species) To follow POGC s policy of protecting the mangrove Because it provides ecological services free of charge Ecosystem : A dynamic complex of plant, animal and micro-organism communities and their non-living environment interacting as a functional unit. Ecological services : Benefits people obtain from mangrove: - Provisioning services (rearing fish to support fishing, cleaning water); - Regulating services (regulation of floods, drought, land degradation, and disease); - Supporting services (soil formation and nutrient cycling); - Cultural services (recreational, spiritual and others)

28 What YOU can do to protect mangrove Try to create awareness among as many people as possible Use the shoreline in less-sensitive or designated areas only Do not feed mangrove branches to livestock Do not use wood from the mangrove for campfires Do not drive cars or motorcycles through the area Do not litter

29 Your contribution will make the difference Mangrove Action Project

30 References 1. International Union for Conservation of Nature ( 2. Food and Agriculture Organization ( 3. Centre for Tropical Ecosystems Research ( eprotectmangroves.htm Mangrove Action Project ( La revue de Téhéran (