Slide 1: MANGROVE BIODIVERSITY AND CONSERVATION By
Feryal Jamal Kherissat Mangrove Forests : Mangrove Forests The term “mangrove” refers to a tidally influenced wetland ecosystem within the intertidal zone of tropical and subtropical latitudes.
Mangrove also designates the marine tidal forest that includes trees, shrubs, palms, epiphytes and ferns.
Mangal :Community of organisms (plants, animals) in the mangrove habitat. Mangroves : Mangroves Based on physiological attributes.
54 species total world-wide.
Principally: Avicenniaceae and Rhizophoraceae
These two families include 25 spp.
60 mangrove associate species in 46 genera. Scientists theorize that the earliest mangrove species originated in the Indo- Malayan region, where there are far more mangrove species than anywhere else in the world. Slide 4: Not all mangroves are obligated to live in saline intertidal areas.
Plants that are confined to the mangrove are called true mangroves.
Develop morphological specialisations and special physiological mechanisms to adapt to the mangrove environment.
Taxonomically isolated from terrestrial relatives, occur only in mangrove forests and can form pure stands.
plants that can also occur elsewhere are called mangrove associates. The principal species of mangrove plants : The principal species of mangrove plants Number of species of associated biota recorded from mangroves in the various geographic regions of the world. : Number of species of associated biota recorded from mangroves in the various geographic regions of the world. Asia Mangrove Location : Mangrove Location Found in tropical areas only
Within the 20ºC isocline.
More southern on East side of continents.
Due to southward moving warm Equatorial currents there.
Primarily in brackish water salty and fresh mix.
Cover approximately 22 million hectares in tropical and subtropical coasts. Slide 8: World Distribution of Mangroves Mangrove forests or mangals grow at tropical and subtropical latitudes near the equator where the sea surface temperatures never fall below 16°C. Mangals line about two-thirds of the coastlines in tropical areas of the world : Mangrove forests or mangals grow at tropical and subtropical latitudes near the equator where the sea surface temperatures never fall below 16°C. Mangals line about two-thirds of the coastlines in tropical areas of the world Mangrove area coverage by region : Mangrove area coverage by region Mangrove area coverage by country : Mangrove area coverage by country Characteristics of Mangal : Characteristics of Mangal Inundation with tides.
Increasing salinity towards ocean.
Sandy clay soil
Nitrogen and Phosphorus are limiting
Limiting mangrove growth only.
Organic nutrients deposited via siltation
Fresh water streams and down-shore currents
Most all are of terrestrial origin.
In sum: Mangal is a harsh place to live Most Common Species : Most Common Species Red Mangrove ……….. (Rhizophora mangle).
Black Mangrove …………. (Avicennia germinans).
White Mangrove ………… (Laguncularia racemosa)
All are found throughout tropics
Buttonwood…………… (Conocarpus erecta)
Is called a mangrove associate Slide 14: White
Laguncularia racemosa Red
Rhizophora mangle Black
Avicennia germinans Bark Identification : Bark Identification Black White Red Small pebbles Square & Smooth Columns & Smooth Tree Characters : Tree Characters Black White Red pneumatophores
(aerial roots) prop roots No prop roots Pneumatophore : Pneumatophore Black White Red White at base,
Out of soil Pencil thin,
Out of soil Bulbous, Off
The root Flower : Flower Red Black White Mangrove Adaptations : Mangrove Adaptations Salt tolerance
Sequester in tissue (bark, stem, root).
Secrete through leaves.
Varies within and between species.
Through growth stages.
Tolerant of soils low in oxygen
Tidal Inundation and adaptations for gas exchange
Pneumatophores and other aerial root extensions.
Aerenchyma : tissue for air storage.
Low soil stability, Shore morphology, and adaptations for rooting
Prop Roots. Slide 20: Salt crystals formed on
grey mangrove leaf Glands on the leaf-stalks and
leaf-blade are conspicuous and
distinctive in shape and position. Salt tolerance Slide 21: Pneumatophore:
Vertical root structures for air exchange. Rhizophores or pneumatophores: These structures can have bark rich in lenticels to function in gas exchange for roots that are constantly in water saturated soil. Slide 22: Lenticels: tiny pores for air exchange. Slide 23: Low soil stability Mangrove Consequences of Adaptations : Mangrove Consequences of Adaptations Greater root mass
Relative to rest of plant and relative to non-mangrove species.
For water exchange and air exchange.
Lower growth rates
Consequence of salt and air exchange.
Tradeoff between salt tolerance and frequent inundation
Can adapt for one or other.
Not both. Mangrove Pollination : Mangrove Pollination Pollination method varies by species
bat or hawk moth (Sonneratia).
birds and butterflies (Bruguiera).
fruit flies (Nypa).
other small insects (Ceriops, Kandelia). Mangrove Reproduction : Mangrove Reproduction Vivipary normal: Reproduction and growth while still attached to plant
Propagule growth Young propagule a.k.a. Hypocotyl Mature propagule Mangrove Dispersal : Mangrove Dispersal Maturity Drop off maternal plant.
Float horizontally initially
Dispersal to novel environments ideally.
Float vertically with appropriate environmental conditions.
Rooting and growth Mangrove seedlings of Avicennia ) species) washing up on a nearby beach show the characteristic precocious germination. In one species a raft of several seedlings are usually found held together by tangled roots (left), suggesting they germinated prior to being dispersed. The shoots are well extended beyond the cotyledons that remain wrapped around the stem. The other seedlings of the other species are found singly (right). These show the two cotyledons still folded together; the shoot has just begun to emerge, but the roots are well developed : Mangrove seedlings of Avicennia ) species) washing up on a nearby beach show the characteristic precocious germination. In one species a raft of several seedlings are usually found held together by tangled roots (left), suggesting they germinated prior to being dispersed. The shoots are well extended beyond the cotyledons that remain wrapped around the stem. The other seedlings of the other species are found singly (right). These show the two cotyledons still folded together; the shoot has just begun to emerge, but the roots are well developed This group of seedlings has begun establishment among debris in the outer intertidal zone : This group of seedlings has begun establishment among debris in the outer intertidal zone Low tide exposes the mudflat adjacent to a mangrove forest and a forest of young seedlings. The margin of this forest has remained stable for several years, so most of these seedlings will probably not survive and become established. If sediment continues to accumulate, augmented by runoff from inland agriculture, the forest margin might expand. : Low tide exposes the mudflat adjacent to a mangrove forest and a forest of young seedlings. The margin of this forest has remained stable for several years, so most of these seedlings will probably not survive and become established. If sediment continues to accumulate, augmented by runoff from inland agriculture, the forest margin might expand. Mangal Habitat Types (from inland to oceanfront) : Mangal Habitat Types (from inland to oceanfront) Riverine
Often found in river deltas.
Constant influx of freshwater.
Great changes in salinity levels.
Inland, behind coastal mangroves.
Little change in tides, no wave action.
Often higher salinity than others (evaporation).
Coastal front habitats.
Unstable morphology due to coastal erosion. Mangrove Species Zonation : Mangrove Species Zonation Ecosystem Functions : Serve as an important buffer between sea and land:
Act as filtering system.
Protect costal land.
Trap debris and silt.
Serve as habitat.
Habitats of 1300 species of animals of which 628 mammals, birds, reptiles, fish and amphibians.
Mangroves are used for various purposes.
Are important in terms of aesthetic and tourism. Ecosystem Functions Slide 34: Among the most productive ecosystems on earth
Global coverage of 100-230 km² with mean 2.5g C/ m² per day:
25% accumulates in mangrove sediments.
25% is recycled.
50% is exported to the coastal zone.
Annual input into ocean 46 X 10¹² g C
Thus contributes 11% of global total export to ocean.
Annual accumulation of carbon in modern sediments 23 X 10¹²g C/ yr
Makes up for 15% of the C accumulation in modern sediments. Mangroves are used for various purposes : Mangroves are used for various purposes Fire Wood.
Tannin extraction and other by products.
Mangroves swamps are rich in larvae of economically important fishes, prawns, crabs and bivalves.
Mangroves are suitable areas for feeding, breeding and nursery grounds of many aquatic organism and hence importance for aqua culture. Slide 36: Mangrove 20% destruction storm Slide 37: Serious damage to the mangroves was
caused by the force of the tsunami.
(Indonesian) Some of the mangrove trees survived the tsunami wave but subsequently are dying.
(West Coast of Aceh( Estimated loss of original mangrove area in different regions : Estimated loss of original mangrove area in different regions Note: no data given for South America. The Main Threat to Mangrove, by region : The Main Threat to Mangrove, by region Slide 41: Aerial view of mangrove forests that have been cleared for farming and aquaculture Location: Kalimantan, Borneo (Indonesian) Abandoned shrimp farm Slide 42: Rice fields planted on former mangrove forest land Location: Sulawesi (Indonesia ( Slide 43: Tractors clearing forest in Panama Slide 44: Mangrove landfilling in progress – landfill often consists of Gatun formation As mangroves are cut and filled with dredged material(including living coral in at least one case) the vibrant life inthese marine communities disappears – along with theirsupportive role as a nurseries for fish and lobster : As mangroves are cut and filled with dredged material(including living coral in at least one case) the vibrant life inthese marine communities disappears – along with theirsupportive role as a nurseries for fish and lobster Slide 46: mangrove trees are used for house building, furniture, transmission
as well as telephone poles and certain household items less than one percent of all mangroves worldwide are sufficiently protected. At this point, mangrove destruction continues to go unchecked. : less than one percent of all mangroves worldwide are sufficiently protected. At this point, mangrove destruction continues to go unchecked. MANGROVE MANAGEMENT Slide 48: CHALLENGES TO MANGROVE MANAGEMENT Slide 49: Protected Forest ?
reserve areas of pristine forests for biodiversity maintenance, scientific research and education, fisheries support and coastal protection.
Productive Forest ?
sustained yield of forestry and fisheries products.
Reforestation Zone ?
degraded areas of ecological importance, including abandoned culture ponds, that need to be rehabilitated .
Conversion Zone ?
to aquaculture, agriculture, salt beds, etc. not exceeding 20% of total mangrove area, preferably in marginal and previously altered sites. Slide 50: Mangrove habitat around the world can self-repair or
successfully undergo secondary succession in 15-30 years if:
The normal tidal hydrology is not disrupted, and
The availability of waterborne seeds or seedlings (propagules) of mangroves from adjacent stands is not disrupted or blocked.
If normal or near normal tidal hydrology exists but waterborne seeds or seedlings (propagules) cannot reach the restoration site, mangroves can be successfully established by planting. RESTORATION TECHNIQUES Slide 51: A time sequence over 78 months from the completion of hydrologic restoration at West Lake near Fort Lauderdale, Florida. Although no active planting was undertaken, all three Florida mangrove species became established Slide 52: Before After Restoration of arid-zone mangroves in Balandra Lagoon in Baja California Sur, Mexico Slide 53: Mangrove protection belt (1 km wide) of Kandelia candel planted in the Red River Delta, Vietnam
A mangrove protection belt in association with coastal sea dykes in the Red River Delta, Vietnam has
greatly improved coastal protection against typhoons. Slide 54: Mangroves, planted originally as tiny propagules in Tarut Bay, Saudi
Arabia are large trees six years later. An in-situ nursery of black mangrove propagules next to Ras Tanura refinery. LEGAL FRAMEWORK : LEGAL FRAMEWORK National and international legal frameworks are required to provide overall guidance for the conservation and sustainable use of mangrove resources and to ensure protection for mangrove associated biodiversity. Vietnam has enacted a zoning plan for the Lower Mekong Delta featuring a Full Protection Zone (FPZ) for coastal protection, a Buffer Zone for controlled economic activities (40% by area), but retaining 60% forest cover, and an Economic Zone where there are no forest conservation restrictions. The FPZ is to be demarcated with clear signs using both symbolic and written information. Important International and regional agreements that are concerned with mangrove biodiversity conservation and management : Important International and regional agreements that are concerned with mangrove biodiversity conservation and management Ramsar: Convention on Wetlands of International Importance.
CITES: Convention on International Trade in Endangered Species of wild flora and fauna.
CBD: The Convention on Biological Diversity.
Agenda 21: A comprehensive set of programmes of action to promote sustainable development into the 21st.
WHC: World Heritage Convention.
UNFCCC: United Nations Framework Convention on Climate Change and the Kyoto Protocol.
MPA: Marine Protected Areas.
UNCLOS: United Nations Convention on the Law of the Sea. Slide 57: Examples of the legal framework for mangroves Policy
Thailand (2002) has about 170,000 hectares of mangrove forest. The national policy is to increase this area to 200,000 ha by 2006. There is an Office of Mangrove Conservation under the Department of Marine and Coastal Resources, which is a department under the new Ministry of Natural Resources and Environment.
The Philippines has a law prohibiting the cutting of any mangrove forest, whether natural or plantation forest.
In Brazil, it has been illegal to cut mangroves since 1926 and the legislation was amended in 1965 to make it even more restrictive. Some exceptions are permitted, e.g. to allow for important public utilities, such as bridges and electricity lines. Environmental legislation was further strengthened by the law on environmental crime in 1998.
The Global Mangrove Database and Information System (GLOMIS) was started in 1996. It is a searchable database of scientific literature relating to mangroves, institutions and scientists working on all aspects of mangroves, as well as regional projects and programmes related to mangroves Environmental awareness of local communities : Environmental awareness of local communities Capacity development for mangrove management and awareness raising about mangroves is needed at all levels from decision makers in government, to community leaders and educational institutions (teachers,
students and school children). Traditional leaders in Ghana attending a training course on wetlands ecology and management for World Wetlands Day (February 2nd) Slide 59: Community awareness training course on mangrove forests for famers in CaMau, Lower Mekong Delta, Vietnam A community workshop for the Eperara-Siapidara Amerindians, at Laguna Santa Bárbara, the Colombian Pacific coast THANK YOU : THANK YOU