Mangroves provide important ecological functions as transitional zones, nurseries, and carbon sinks. However, they face threats from human activities like deforestation, development, and climate change impacts such as rising sea levels and temperatures. Mangroves help protect coastlines and support fisheries but over 20% have been lost in recent decades. While rising CO2 and temperatures may enhance mangrove growth, the current rapid rate of change leaves less time for adaptation and migration with the loss of coastal areas to development. Management is needed to balance human uses of mangroves with conservation to maintain their critical ecosystem services.

1. Mangroves
Ecosystems
IANA F GRULLÓN P
801-09-2856
WEDNESDAY 14 OCT 2015

2. Mangroves ecosystems
Mangroves
Structure
Distribution
Function
Mangroves as sinks
Mangroves as providers
Challenges mangroves ecosystems are facing
Climate change

3. Mangroves are:
“…an assemblage of tropical trees and shrubs that grows in the intertidal zone. Mangroves include
approximately 16 families and 40 to 50 species (depending on classification).
(K. McKee, 1996)
 Criteria to be a mangrove:
1. Complete fidelity to the mangrove environment.
2. Plays a major role in the structure of the community and has the ability to form pure stands.
3. Morphological specialization for adaptation to the habitat.
4. Physiological specialization for adaptation to their habitat.
5. Taxonomic isolation from terrestrial relatives.
(P. Tomlinson, 1986)

4. Mangroves
Ecosystems that are located in the Tropical and
Subtropical parts of the Globe.
Most of the flora in this ecosystem is capable
of tolerating high salinity levels.
Have the capacity to resist low oxigen levels
in the soils.
Can survive in completly floaded conditions.
(Kathiresan and Bingham, 2001)
IFGP 2014

5. Mangroves structure
Mangroves forests have the following attributes in terms of their structure:
◦ species richness
◦ canopy height
◦ basal area
◦ tree density
◦ age/size class distribution
◦ low understory development
( K. Mckee, 1996 )
Mangroves fallow the detrital type of food web in terms of trophic structure.
(Odum & McIvor 1990)

6. Mangrove distribution
The mangrove infauna consists of species that spend most or all of the adult life within the
substrate, boring into hard substrates or burrowing in soft sediments
“The mangrove epifauna consists of animals that may move over, or are attached to, hard or
soft substrates.”
(Levinton, 2001)
Infauna Sessile Epifauna

7. Mangroves distribution
Mangrove distribution is controlled by:
climate salinity tidal fluctuation sedimentation wave energy
Distribution of this ecosystems has been highly reduced due to human activities.
World Atlas of Mangroves by ITTO

8. Mangroves functions and services
ECOLOGICAL FUNCTIONS
◦ Transitional zones
◦ Provide shelter
◦ Serve as nursery spots
◦ Sink many contaminants before
reaching the ocean
◦ Highly productive areas
◦ Sites for accumulation of carbon,
nutrients and sediments.
ANTHROPOGENIC SERVICES
◦ Provide wood*
◦ Protect inland areas from tides and
major events such as hurricanes
◦ Host many species of fish
◦ Provide food and medicine resources*
* When used in a sustainable manner.

9. Mangroves as sinks
“Sediments in the coastal zone are normally dominated by terrigenous particles due to the
supply of continental material. With growing industrial activity, contaminants are released into
the coastal environment causing undesirable effects on the marine ecosystem.”
(Natesan et al., 2014)
Mangroves serve as sinks for multiple contaminants including heavy metals. They cause a good
effect by trapping them before they reach the marine environment but affect the delicate
balance of the mangroves themselves and alter quality in which they can develop appropriately
and healthy.

10. Mangroves as providers
They provide resources for species development:
“The infauna of mangrove associated Spartina marshes was investigated by Braga et al. (2009),
who found that increasing macrofaunal diversity and abundance is associated with greater plant
density”
(Beasley et al., 2010)
They provide habitat:
“The sediment surface, roots, living and dead plant material such as logs, branches and leaves
are habitat for the epifauna”
(Beasley et al., 2010)

11. Mangroves challenges
Humans
◦ Construction
◦ Deforestation
◦ Overfishing
◦ Padding
Climate Change
◦ Sea level rise
◦ Temperature rise
◦ Salinity rise
Natural disasters and phenomena
◦ Increase in intensity *
◦ Decrease in frequency *
* As a result of climate change.

12. Human impact on mangroves
Mangroves are very resilent organisms. Although they have been
under constant preasure through the years.
Mangroves have to face humans and survive:
◦ Deforestation:
“...mangrove deforestation is occurring at a rate of 1–2 % per year...”
(Alongi, 2002)
◦ Construction:
Many mangrove ecosystems have been destroy for urban development.
◦ Padding:
Mangroves were pad in the past because they were consider a threat for
human health, they were poorly valued, and necesary for the development
of coastal urban sites.
IFGP 2014

13. Human Impact on Mangroves
“…20% decline in last 25 years due mainly to conversion and coastal development 3-4
times faster than terrestrial forest coastal development…”
(World Atlas of Mangroves by ITTO)
 “Despite high rates of destruction, mangroves still play an important role in human
sustainability and livelihoods in developing nations where poverty is rife and population
growth is high”
( Alongi, 2015)

14. Climate Change
The ICPP predicted several changes in terms of global climate change and among others they found
that for 2081-2100 the measurements of salinity, precipitation and sea level will fallow the below
patterns:
( Alongi, 2015 )

15. Mangroves and Climate Change
Response to rise in temperatures
“Temperature increases alone are likely to result in faster growth, reproduction, photosynthesis,
and respiration, changes in community composition, diversity, and an expansion of latitudinal
limits.”
( Tittensor, 2010)
“An experimental study has shown that juvenile mullet (Liza vaigiensis) and crescent terapon
(Terapon jarbua) frequenting tropical seagrass beds can be acclimated to higher water
temperatures, approaching the critical limits for marine vertebrates. Other organisms such as
tropical gastropods may respond actively by seeking cooler sites to survive when temperatures
exceed 33 °C.”
(Alongi, 2015)

16. Mangroves and Climate Change
Responses to rising CO2 :
“Higher CO2 concentrations can enhance the growth of mangroves, but responses are species-
specific...”
“The simulation analysis suggests that temperature changes will be a more important driver
than increasing CO2 and that different mangrove species will differ in their sensitivity to
increases in both drivers.”
( Alongi, 2015)
“Furthermore, feedbacks may exist between CO2 concentrations, root
biomass, and elevation gain”
(Saintilan, 2014)

17. Mangroves and Climate Change
Response in rising sea level
“Over geological time, as sea level has waxed and waned in
relation to alternating periods of glaciation and warming,
mangroves have had to adjust (or not) to rises and falls in sea
level.”
(Alongi, 2015)
The key issue with the current rate of sea rising is that
mangroves will not have the time they need to migrated so
safer zones or make the physiological and morphological
adaptations to survive in the new conditions.
Nor they will have space to migrate because of urban
development which varies from past periods of glaciation and
warming.

18. Thank you for your attention!
iana.fgrullonpenkova@gmail.com
IFGP 2014

19. Discussion Questions
1) Which attributes of mangroves can benefit both humans and the environment, and how can
we manage them in good manner?
2) How can we establish the level of sustainability in which activities involving mangroves are
done and what management approaches can be taken to assure the best possible practices in
this ecosystem?
3) Which do you think is the best approach in the debate for mangrove protection ?
4) Having in consideration the lack of space for mangroves to migrate inland as consequence of
sea level rise, what do you propose it should be done ?
5) What technical measurements can we propose for the reduction of sedimentation in the
mangrove ecosystems and the other environment linked to this one?
6) How are mangroves important for the economy and how their best state and health favors
Puerto Rican economy?

20. References
Alongi, D. M. 2015. The Impact of Climate Change on Mangrove Forests. Curr. Climate Change Repository. Springer International Publishing.
Alongi, D. M. 2002. Present state and future of the world’s mangrove forests. Environ Conserv. 29:331–49
C.R. Beasley, M.E.B. Fernandes, E.A.G. Figueira, D.S. Sampaio, K.R. Melo, and R.S. Barros. 2010. Mangrove Dynamics and Management in North
Brazil. Volume 211 of the series Ecological Studies. 109-123
Janzen, D. H. 1985. Mangroves: where’s the understory. Journal of Tropical Ecology 1: 89-92.
Kathiresan, K., and B. L. Bingham. 2001. Biology of mangroves and mangrove ecosystems. Advances in Marine Biology, Vol 40 40:81-251.
McKee, K. 1996. Mangrove Ecosystems: Definitions, Distribution, Zonation, Forest Structure, Trophic Structure, and Ecological Significance.
Smithsonian Environmental Research Center, Smithsonian Institution.
Natesan, U., Kumar, M., Deepthi, K. 2014. Mangrove sediments a sink for heavy metals? An assessment of Muthupet mangroves of Tamil Nadu,
southeast coast of India. Springer-Verlag Berlin Heidelberg.
Odum, W.E. and C.C. McIvor. 1990. Mangroves.. In Ecosystems of Florida, R. L. Myers and J. J. Ewel (eds.). University of Central Florida Press.
517-548
Saintilan N., Rogers K. 2014. Woody plant encroachment of grasslands: a comparison of terrestrial and wetland settings. New Phytol.
Tittensor DP, Mora C, Jetz W, Lotze HK, Ricard D, Vanden Berghe E, et al. 2010. Global patterns and predictors of marine biodiversity across
taxa. Nature, 466:1098–101.
Tomlinson, P. B. 1986. The botany of mangroves. Cambridge University Press, Cambridge, United Kingdom.