Odyssey Expeditions - Mangroves 1 NOAA Mangroves By Dave Cabrera

Odyssey Expeditions - Mangroves 2 Introduction Mangroves – Halophytic (salt tolerant) trees that live in areas predominantly saturated with salt water Found along coastlines between 32 degrees N and 38 degrees S families and species (classification dependent) Highest diversity in Asia New world has 12 US has 4 (species we will discuss) 25% of Caribbean coastline 75% of continental regions

Odyssey Expeditions - Mangroves 3 Adaptations to Salt Water Salt pores – located on leaves, root and branches. Excess salt absorbed from soil secreted Salt exclusion – roots of some mangroves exclude salt Viviparity – seeds germinate while attached. Fully developed seedlings drop from tree.

Odyssey Expeditions - Mangroves 4 Adaptations to Low Oxygen in Soil Prop Roots – roots exposed to air (red mangroves) Pneumatophors – pencil- like roots that stick up from the substrate (black mangroves) Lenticels – slits in the bark and roots Aerenchyma – air spaces that allow gas to reach underground roots NOAA PneumatophorsLenticels Prop roots Odyssey Expeditions

Odyssey Expeditions - Mangroves 5 Role of Mangrove Ecosystem Mangroves as a Buffer –Protects coastline from wave action –Prevent erosion, and keep sediments from reaching coral reefs –Collect and stabilize sediments NOAA

Odyssey Expeditions - Mangroves 6 Role of Mangrove Ecosystem It has been highly debated as to whether succession occurs in mangroves. The evidence is inconclusive as to whether this happens and is considered hypothetical.

Odyssey Expeditions - Mangroves 7 Role of the Mangrove Ecosystem Mangroves as a nursery and a habitat –Detritus from leaves – Bacteria feed off detritus –Bacteria – provide food for planktonic organisms –Plankton – Serve as food for larval and juvenile fish and invertebrates –Shelter – protection from predators NOAA Odyssey Expeditions

Odyssey Expeditions - Mangroves 8 Roll of mangrove ecosystem Diversity of species in mangroves –Trees – species in families –Poriferans – sponges grow on prop roots –Annelids – segmented worms live in mud and among prop roots –Cnidarians – anemones occupy prop roots –Molluscs – Gastropods (periwinkles) and bivalve (oysters) found on prop roots –Echinoderms – Sea cucumbers, sea stars –Urochordates – tunicates attach to roots –Birds – use tree tops –Fish – swim among roots –To name a few NOAA Odyssey Expeditions

Odyssey Expeditions - Mangroves 9 Species of Mangroves Red Mangrove (Rhizophora mangle) –Location – found nearest to water –Leaves elliptical and leathery. Dark green on top, pale green underneath –Prop roots – large aerial roots extend from tree into ground –Roots submerged –Tolerant of low oxygen NOAA Odyssey Expeditions

Odyssey Expeditions - Mangroves 10 Red Mangrove Dispersal Seedling dropped from tree Floats root down in water When it comes in contact with substrate it takes root and grows Can float around for over a year

Odyssey Expeditions - Mangroves 11 Red Mangrove Dispersal

Odyssey Expeditions - Mangroves 12 Species of Mangroves Black Mangrove (Avicennia germinans) –Location – Shoreward of red mangroves –Leaves – Oblong. Dark green on top, pale grey to white underneath. Often encrusted with salt. –Pneumatophores – Pencil-like root extensions that provide surface area for gas exchange –Roots submerged only at high tide –Tolerant of low oxygen NOAA

Odyssey Expeditions - Mangroves 13 Species of Mangroves White Mangrove (laguncularia racemosa) –Location – Terrestrial side of mangrove stands. Behind black mangroves. –Leaves – Broad flattened and oval. Leaves branch out from stem opposite to each other –Salt Pores – Present at base of leaves –Soil fully saturated with water –Tolerant of salty soils –Less tolerant of high water NOAA

Odyssey Expeditions - Mangroves 14 Species of Mangroves Buttonwood (Conocarpus erectus) –Location – Terrestrial side of mangrove stands, behind black mangroves. Not a true mangrove –Leaves – Elliptical and leathery. Dark green on top, pale green underneath –Salt Pores – Present at base of leaves –Soil is damp, but not saturated –Tolerant of salty soils –Not tolerant of high water NOAA

Odyssey Expeditions - Mangroves 15 Threats to Mangrove Ecosystem Deforestation –Coastal development –Shrimp farming –Flooding –Charcoal and timber industry Rice Shrimp and development

Odyssey Expeditions - Mangroves 16 Threats to Mangrove Ecosystem Pollution –Point source pollution – sewers, industrial discharge, oil spills –Non-point source pollution – agriculture runoff NOAA Oil