Tropical coastal ecosystems.pptx

1. Tropical coastal
ecosystems
Values, issues and goals
for conservation of
Submitted by,
Ancy Varghese
II MSc Botany, Roll no.6
Submitted to,
Dr. Arya P Mohan
St. Teresa’s college,EKM

2. Contents
• Introduction
• The values of coastal ecosystems
• The issues of coastal ecosystems in
the tropics
• Goals for conservation and
management of tropical ecosystems
5/21/2024
Tropical coastal ecosystems 2/

3. Introduction
• Coast is the edge of the land where it meets the sea or ocean.
• The term coastal zone can be used instead of a spatial zone where the interaction of the
sea and land processes occurs.
• Coastal habitats have biodiverse marine populations that vary by topography and
climate.
• Bays, estuaries, mangroves, salt marshes, and wetlands…etc are examples of coastal
ecosystems. Among that mangroves, sea grasses and coral reefs are the major tropical
coastal ecosystems in the world.
• Coastal ecosystems are generated by plants and other animals that can thrive in saltwater
and fluctuating tides.

4. • Many fish, turtles, and migratory birds nest in coastal
locations because of the food and protection from the
deep ocean.
• Human activities, natural disasters, and invading
animals can disrupt these communities.
• Coastal organisms thrive due to abundant sunlight and
nutrition. Shallow coastal waters let sunlight reach the
ocean floor, where dead organisms nourish life.
• Sunlight can only reach 50 to 100 meters into the
water, therefore nutrients sink too deep to support
most living species.

6. Values of coastal ecosystems : 1) Ecological
• Nutrient cycling:Mangrove forests and seagrass meadows are coastal ecosystems of
intense nutrient cycling, whereas the coral reef areas are poor in nutrients and hence, the
nutrient-rich coastal systems supply nutrients to adjacent coral reefs.
• Breeding station & Habitat: The mangroves and seagrass provide nursery grounds for
many faunal species, while the coral reefs provide habitat for them.
• Protection:The mangroves protect seagrass beds and coral reefs from landward
discharges and sedimentations; the coral reefs also protect the other systems by buffering
ocean currents and dissipating wave action.

7. • Climate regulation & Role in carbon cycle
• regulate the climate by absorbing carbon
dioxide and other greenhouse gases, as well
as providing protection against storms and
erosion.
• Coastal ecosystems play a critical role in
global climate and the carbon cycle by
sequestering carbon.
• Carbon storage rates per unit area exceed
those of terrestrial ecosystems.
• For the coastal ecosystems examined here,
mangroves, salt marshes, and seagrasses
combine to sequester a minimum of 136 000
tonnes C into long-term storage annually.

8. 2). Economical
• Coastal ecosystems are also economically important.
• Commercial fishing & food: They provide a range
of goods and services, including fish and seafood
fisheries management, alternative food sources.
• Tourism, and recreation: In fact, coastal tourism is
one of the largest industries in the world, generating
billions of dollars in revenue each year.
• Medicine & pharmaceuticals
• Education and research

9. Interconnectivity of coastal ecosystems
• The successful connectivity between the three ecosystems is
vital for fishery resources, nutrient balance and mitigation of
climate change.
• Interactions between the ecosystems are not only the state of
the biodiversity enrichment but also the flow of nutrients and
energy.
• The deleterious effect of any one ecosystem will directly or
indirectly affect the other ecosystems.
• It is a matter of necessity to conserve coastal ecosystems
simultaneously in order to ensure a better goods and ecosystem
services.

10. Coastal
Ecosystem
Provisioning and
Cultural
Regulating Supporting
Coral Reefs Recreation and tourism, fish
and shellfish harvesting,
raw materials, education
and aesthetics
Storm protection, nutrient
cycling
Biological diversity,
ecological connectivity,
habitat for fish and shellfish,
nursery and protective
habitat
Seagrass beds and salt
marshes
Fish and shellfish
harvesting, raw materials,
wildlife harvesting,
education and aesthetics
Storm protection, erosion
control, water purification,
oxygen cycling, nutrient
cycling, carbon storage and
sequestration
Biological diversity,
ecological connectivity,
nursery and protective
habitat for fish, shellfish and
wildlife
Mangroves Fish and shellfish
harvesting, raw materials,
education and aesthetics
Storm protection, nutrient
cycling and erosion control,
water purification, oxygen
cycling, carbon storage and
sequestration
Biological diversity,
ecological connectivity,
nursery and protective
habitat for fish, shellfish and
wildlife

11. Coastal
Ecosystem
Provisioning and
Cultural
Regulating Supporting
Oyster reefs Shellfish harvesting, raw
materials, education and
aesthetics
Storm protection, erosion
control, water purification,
nutrient cycling, carbon
storage and sequestration
Biological diversity,
ecological connectivity,
nursery and protective
habitat for fish and shellfish
Beach, dune and shore Recreation and tourism,
education and aesthetics
Storm protection, erosion
control
Biological diversity,
ecological connectivity,
nursery and protective
habitat for shellfish and
wildlife
Bays and estuaries Recreation and tourism, fish
and shellfish harvesting,
raw materials, wildlife
harvesting, education and
aesthetics
Storm protection, erosion
control, water purification,
oxygen cycling, carbon
storage and sequestration,
nutrient cycling
Biological diversity,
ecological connectivity,
nursery and protective
habitat for fish, shellfish and
wildlife

12. Issues faced by coastal ecosystems
• All major coastal ecosystems are experiencing degradation throughout tropical regions of
the world.
• Coral reef - “considered as the largest durable bioconstruction projects on earth” , but
overall, 30% of global coral reefs are already severely damaged and 60% may be lost by
2030.
• Recovery of coral reefs will be slow or not occur at all when they experience multiple
stressors .
• The Indo-Pacific region contains 75% of the world’s coral reefs and has experienced
substantial declines in coral cover.

13. 1. Habitat loss and modification
• Mainly by the demands for aquaculture, port
construction, trawling, road construction, and the
building industry . Results in decreased species
diversity and abundance.
• Approximately 75% of sheltered tropical coasts
worldwide were once occupied by mangroves, but
this figure is nowadays probably closer to 25% .
• The use of mangroves and seagrass as nursery
habitats by many coastal species, including
commercially important species, highlights the more
widespread impacts that are felt from loss of these
habitats.

14. • In the case of seagrass beds, for instance, recreational boating may lead to introduction of
pathogens, pollutants, or invasive species that can disrupt the life cycle of native organisms.
• Similarly, high boating traffic may result in physical disturbance of the seafloor, which will
result in deterioration of the sea grass beds and thus result in lower levels of regulating
services such as water purification, carbon sequestration, and erosion control.
• Thus, there may be conflict between different types of ecosystem services where humans’ use
of one service may hinder production of other services.
• In some cases, use of cultural and provisioning services may cause deterioration or reduction
in regulating and supporting services.
• Conversely, enhancement of a particular ecosystem service may result in complementary
enhancements to other services produced by the same ecosystem.
• For example, restoration of oyster reefs to mitigate the effects of eutrophication also results in
the creation of habitat for finfish.

15. • 2. Invasive species
• an increasing cause of change in coastal
ecosystems .
• Invasive species impact fisheries, local ecological
interaction, and coastal infrastructure and the
impacts will be difficult to reverse.
• The major route of transfer of invasive species is in
ship’s ballast water. Ships began using water to
control their draught, trim and heel in the last
nineteenth century in place of solid materials.
However, it is only in recent years with the advent
of larger tankers travelling at faster speeds that the
chance of successful transfer of organisms around
world.

16. 3. Climate change
• one of the dominant causes of change in coastal
ecosystems, especially mangroves, coral reefs and beaches,
through its potential impacts on rise in sea-level, storm
frequency, sea temperatures, and oceanographic processes
such as upwellings and surface currents. Impacts will be
difficult to reverse and are likely to manifest as coral
bleaching, coastal erosion, alterations in plankton
delivery to coastal zones, and altered calcification
processes arising from changes in ocean chemistry.
4. Spread of infectious disease
5. Over exploitation of species for fish meal

17. 6. Nutrient loading
• Nutrient load means the total amount of a nutrient such as nitrogen or phosphorus entering the
water during a given time, such as “tons of nitrogen per year”, or “pounds of phosphorus per
day.”
• Nutrients may enter the water from runoff, groundwater recharge, point source discharges, or
the air (in the form of wet deposition such as rain or snow as well as dry deposition).
7. Sedimentation
• Ocean sediment, or seafloor sediment, are deposits of insoluble particles that have accumulated
on the seafloor.
• These particles have their origins in soil and rocks and have been transported from the land to
the sea, mainly by rivers but also by dust carried by wind and by the flow of glaciers into the
sea. Additional deposits come from marine organisms and chemical precipitation in seawater, as
well as from underwater volcanoes and meteorite debris.

18. 8. Pollution
pollution from agricultural runoff, wastewater, and plastics is
also harming coastal ecosystems,
• Coastal development, including the construction of ports,
marinas, and other infrastructure, can also have negative
impacts on coastal ecosystems,
• the extraction of resources such as oil and gas.
• Changes in water quality.
• These threats are complex and interconnected, and
addressing them requires a multifaceted approach that takes
into account the many factors that contribute to their
persistence.

19. Goals for conservation & management of tropical coastal ecosystems
• Conservation and management are more likely to succeed when they are planned with
reference to goals or guiding principles that are based on ecological and socio-economic
understanding.
1. Providing for resilience: Tropical ecosystems are affected by anthropogenic and natural
disturbances such as storms, coral bleaching, crown-of-thorns starfish, invasive species,
shipwrecks, pollution events, disease, and fishing. Resilience is the ability of an
ecosystem to recover from a disturbance and maintain its production of goods and
services.
2. Protect water quality.
3. Conservation and recovery of species-at-risk
4. Conservation of representative samples of species and assemblages.
5. Understanding the socio-economic context. 6.Education

20. 7. Maintenance/ restore connectivity
• Connectivity is the linkage of spatially disjunct populations and systems via dispersal of
eggs and larvae, the movements of juvenile and adult organisms, and the passage of water
masses
• Tropical ecosystems are connected at a range of spatial and temporal scales: (i) across
environments e.g. via the flow of water and its constituents from catchments to estuaries
and then to coral reefs ,
• (ii) across ecosystems e.g. seagrass, mangroves, coral reefs by the ontogenetic and diurnal
migrations of fishes (iii) between examples of a single system e.g. between coral reefs by
between-reef movement of larvae or adult fishes migrating to spawning aggregation sites,
and
• (iv) within a single habitat e.g. return of larval fishes to their natal reef , the diurnal
movements of fishes between reef habitats, or the ontogenetic movements by coral reef
fishes among reef habitats

21. Coastal ecosystem of India
• Coastal ecosystem of India spread over nine states and four union territories which also
include two islands under Indian territory.
• India has diverse coastal features along its vast coastline of 7515.6 km, consisting of
mangroves, coral reefs, seagrass meadows, and salt marshes.
• India also has the largest lagoon in Asia, and there are few more lagoons on both east and west
coast. A sizeable population lives near the Indian coast, and there are many prominent cities on
the coast.
• Of the four metropolitan cities, three of them Mumbai, Kolkata and Chennai are coastal cities.
• However, with the onset of climate change and increasing anthropogenic pressures, Indian
coasts are vulnerable and need robust policies for their protection, conservation and
management.

22. A mission of India
• Sustainable Development Goals
(SDG): As per the 14th SDG of the
United Nations, India has certain
targets to conserve coastal areas.
These include preventing and
reducing marine pollution by 2025.
NITI Aayog ( National institution
for transforming India) was
responsible to oversee SDG
implementation.

23. Reference
• Economidou, E. (1982). The ecological value of coastal ecosystems. Ekistics, 49(293), 98–
101. http://www.jstor.org/stable/43619581
• Kandasamy Kathiresan and Nabeel M. Alikunhi, 2011. Tropical Coastal Ecosystems:
Rarely Explored for their Interaction!. Ecologia, 1: 1-22
• MAJOR COASTAL ENVIRONMENTAL ISSUES.” National Research Council. 1994.
Priorities for Coastal Ecosystem Science. Washington, DC: The National Academies Press.
Doi: 10.17226/4932.
• National Academies of Sciences, Engineering, and Medicine. 1994. Priorities for Coastal
Ecosystem Science. Washington, DC: The National Academies Press.
https://doi.org/10.17226/4932.
• Gladstone, William.,(2009) Conservation and Management of Tropical Coastal
Ecosystems10.1007/978-90-481-2406-0_16- Ecological Connectivity among Tropical
Coastal Ecosystems

24. Thank you