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Wetland
1. Vegetated areas that are covered with water or
have very wet soils for part of the year.
2. Wet areas without vegetation,
Most documents focus on vegetated areas because
wetland plants provide a unique habitat and other
benefits to fish that unvegetated areas do not
provide.
Seagrass meadow Mangrove Saltmarsh
climateshifts.org
Mangrove
Mangroves are various kinds of trees up to
medium height and shrubs that grow in saline
coastal sediment habitats in the tropics and
subtropics
Distribution: mainly between latitudes 25° N and
25° S; dominate three-quarters of tropical
coastlines.
This habitat is characterized by a depositional
coastal environments, where fine sediments ,
often with high organic content, collect in areas
protected from high-energy wave action.
ozcoasts.gov.au
The saline conditions range from brackish water,
through pure seawater (30 to 40 ppt), to water
concentrated by evaporation to over twice the
salinity of ocean seawater (up to 90 ppt; part
per thousand).
Mangrove (source: en.wikipedia.org)
The word is used in at least three senses: (1) most broadly to
refer to the habitat and entire plant assemblage or mangal for
which the terms mangrove forest biome, mangrove swamp and
mangrove forest are also used, (2) to refer to all trees and large
shrubs in the mangrove swamp, and (3) narrowly to refer to the
mangrove family of plants, the Rhizophoraceae, or even more
specifically just to mangrove trees of the genus Rhizophora.
The remaining mangrove forest areas of the world in
2000 was 53,190 square miles (137,760 km²)
spanning 118 countries and territories.
Source: Exploring Taiwan Mangrove
• 在台灣符合此定義的現存紅樹林植物只有
紅樹科的水筆仔、五梨跤、使君子科的欖
李及馬鞭草科的海茄苳等四種。當然，在
台灣的濱海地區還有各種植物，包括紅樹
林的的伴生植物，例如苦林盤、黃槿、土
沈香等，另外還有禾本科之雲林莞草、鹽
地鼠尾粟、濱刺麥及林投、草海桐、鹽地
等海濱植物-
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Black Mangroves or 'Courida'
(Avicennia germinans)
Red Mangrove or 'Red Mango'
( Rhizophora mangle )
White Mangrove
( Laguncularia racemosa )
Source:
www.mangrovesgy.org/index.php?option=com
boripat.ac.th
Hypocotyl: The part of the stem of an
embryo or of a seedling between the
radicle and the cotyledons ; cactus-art.biz
種子和發芽情況; y3c2.blogspot.com
Special Type of Germination: Vivipary
source: tutorvista.com
In viviparous germination, the seeds
germinate while still attached to the parent
plant. The embryo grows out of the seed
and then out of the fruit and projects from it
in the form of a green seedling幼苗
displaying the root and the hypocotyl.
Due to the increase in weight the seedling
separates from the parent tree and falls
into the water and develops lateral roots.
Vivipary is seen in Rhizophora, Cercops,
Kandelia and Sonneratia.
Radicle:胚根; hypocotyl:下胚軸; seed or progragule
en.wikipedia.org
• Mangrove plants require a number of
physiological adaptations to overcome the
problems of anoxia, high salinity and frequent
tidal inundation. Each species has its own
solutions to these problems; this may be the
primary reason why, on some shorelines,
mangrove tree species show distinct zonation.
Therefore, the mix of species is partly determined
by the tolerances of individual species to physical
conditions, like tidal inundation and salinity, but
may also be influenced by other factors such as
predation of plant seedlings by crabs.
En.wikipedia.org
• Once established, mangrove roots provide an
oyster habitat and slow water flow, thereby
enhancing sediment deposition in areas where it
is already occurring. The fine, anoxic sediments
under mangroves act as sinks for a variety of
heavy (trace) metals which colloidal particles in
the sediments scavenged from the water.
Mangrove removal disturbs these underlying
sediments, often creating problems of trace
metal contamination of seawater and biota.
En.wikipedia.org
• Mangrove swamps protect coastal areas from erosion,
storm surge (especially during hurricanes), and
tsunamis. The mangroves' massive root systems are
efficient at dissipating wave energy. Likewise, they slow
down tidal water enough that its sediment is deposited
as the tide comes in, leaving all except fine particles
when the tide ebbs. In this way, mangroves build their
own environment. Because of the uniqueness of
mangrove ecosystems and the protection against
erosion they provide, they are often the object of
conservation programs, including national biodiversity
action plans.
En.wikipedia.org
emeralddiving.com; bryozoan苔蘚蟲
The unique ecosystem found in the intricate
mesh of mangrove roots offers a quiet marine
region for young organisms. In areas where
roots are permanently submerged, the
organisms they host include algae, barnacles,
oysters, sponges, and bryozoans, which all
require a hard surface for anchoring while they
filter feed.
Shrimps and mud lobsters use the muddy
bottoms as their home. Mangrove crabs mulch
the mangrove leaves, adding nutrients to the
mangal muds for other bottom feeders. In at
least some cases, export of carbon fixed in
mangroves is important in coastal food webs.
Mangrove plantations in Vietnam, Thailand,
the Philippines and India host several
commercially important species of fish and
crustaceans. Despite restoration efforts,
developers and others have removed over half
of the world's mangroves in recent times.
Young lemon sharks use mangroves
as a nursery area.laststands.
kennedywarne.com
This is the foodweb of a Mangrove Ecosystem
w3.shorecrest.org
This is the foodweb of a Mangrove Ecosystem
w3.shorecrest.org
The microbial food web. After Conover(1982);
pcwww.liv.ac.uk
浮游動物
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箭蟲(毛頜類)
海樽
橈足類
磷蝦
水母
櫛水母
Size groups of planktons; Adapted from Sieburth et. al. 1978; msource: hpl.umces.edu
氮循環
The Nitrogen Cycle - important to fish keeprs
princeton.edu
fishdoc.co.uk
Nitrite:NO2亞硝酸鹽; nitrate硝酸鹽: NO3; Both are anions陰離子, or io離子with a negative charge
Mangrove products: timber, fuel wood and charcoal, dye, corrosion inhibitor
Tannins and dyes: Bark of mangrove trees
are harvested as a source of tannin for the
tanning industry. High tannin content is
found especially in members of the
Rhizophoraceae, to increase their
resistance to herbivores. With development
of cheap synthetic tannic acids after World
War II, the commercial exploitation of
mangrove bark has dropped to practically
zero. Mangrove sap is, however, still used
by East Africans or Polynesians to make
the black dye for tapa cloth.
http://mangrove.nus.edu.sg/guidebooks/text/1022.htm
Topics for discussion
• Using mangrove in fish culture
• Interrelationship between mangrove, seagrass
meadow and coral reef ecosystem--evidence
Mangrove is used in Thailand to
control the water quality in fish ponds
Supplementary reading
• Biology of mangrove:
ocw.unu.edu/...mangroves/Biology-ofmangroves.pdf