Chapter 1: Introduction
1.1 Overview
Mangroves are very prevalent coastal ecosystems found in tropical and subtropical
regions. They serve as crucial habitats, offering shelter and sustenance to a diverse range of
creatures, including nearshore fisheries. Additionally, they play a significant role in
regulating the coastal economy and supporting livelihood management via both direct and
indirect means. Mangroves are crucial assets of coastal areas that play a significant role in our
socio-economic progress. These significant resources are in tropical and subtropical climates,
namely in areas where freshwater and saltwater meet. Mangroves are regarded as valuable
natural resources due to their ability to sequester carbon, act as coastal barriers, protect
shorelines, provide food, fuel, and construction materials, and safeguard biodiversity
(Halpern et al. 2008).
1.2 Background of the Study
Coastal and estuarine ecosystems are among the most impacted natural systems on
Earth (Lotze et al. 2006, Halpern et al. 2008). The deterioration of this ecosystem resulted
from the combined effects of human activities and global climate changes, leading to an
escalation in the severity of these damages. In this connection, a small natural feature (SNF)
is described as a site that holds ecological significance that is not proportional to its size. This
can be due to its provision of resources that restrict important populations or processes that
impact a much larger area. Alternatively, it can be because the site supports exceptional
diversity, abundance, or productivity. The identification and handling of minor natural
features as separate entities serves mainly as a method to aid the practical preservation of the
biodiversity and ecosystem services they are connected to. (Hunter, 2016). Marine
Submerged Natural Features (SNFs) may be found at various depths and latitudes, including
diverse habitats such as tropical coral reefs, seagrass meadows, and mangrove forests, as well
as deep-sea coral reefs, sponge gardens, and hydrothermal vents. Nevertheless, there are
several maritime Submerged Natural Features (SNFs), such as rhodolith beds, that remain
relatively obscure and have not been adequately mapped. Consequently, their biological
significance is likely to be underestimated (Foster, 2001). Marine SNFs differ from terrestrial
SNFs due to their presence in a fluid environment. This fluid nature of marine systems allows
for connectivity within and between habitats and ecosystems, including the movement of
populations (through adult, juvenile, and larval dispersal) as well as nutrients and materials.
Marine SNFs are commonly formed by biogenic processes, which involve the construction of
structures using living plants and animals, or the use of remains from living species. many
biogenic SNFs, such as deep-sea coral reefs, have a long lifespan and experience sluggish
growth. As a result, the ability of these SNFs to recover from disturbances can be restricted
and extended, often requiring many decades to centuries after the disturbance has ended
(Clark et al., 2016). The age of biogenic SNFs, which refers to the time since a disturbance
event, is closely linked to the benefits they offer. It also preserves a portion of the habitat in a
mature state to maintain its ecological advantages. Marine small-sized non-filter feeders
(SNFs) are more prone to have low tolerance to stresses and can serve as early indicators of
regime alterations in the surrounding marine environment (Thrush et al., 2016).
The coastal environment is characterised by its high level of dynamism, which is
attributed to a diverse range of resources and habitats, resulting in both cyclic and random
processes. Moreover, the coastal habitats are the most prolific ecosystems on the planet. India
has a coastline that spans over 7500 km, including the coastlines of its island possessions.
The starch of 60 coastal districts and is considered one of the seventeen super-diversified
nations in the world (Cresswell and Murphy, 2017). Multiple coastal regions throughout the
Indian coastline possess abundant marine biodiversity and host distinctive plant and animal
species that require conservation as living natural assets within a marine ecosystem.
Coasts and estuarine ecosystems have a significant impact on the support and
maintenance of life (Zacharia et al., 2014). The vegetation found in coastal areas, including
mangroves, macroalgae, seagrass, and dune plants, has a crucial ecological function in
preserving the coastal environment and its production. Initially, the organic matter generated
by this vegetation increases the biological productivity of the coastal environment. Food
webs sometimes consist of elements that span across several habitats, indicating connections
both in terms of space and feeding relationships across these ecosystems. Trophic
connections across separate ecosystems can arise from the transfer of food supplies and the
migration of consumers (Polis et al., 1997). The interconnections between different habitats
can have significant ecological implications, particularly by enhancing the production of the
receiving region. Marine vegetative ecosystems, including seagrasses, salt marshes,
macroalgae, and mangroves, cover just 0.2% of the ocean surface. However, they are
responsible for 50% of the carbon burial in marine sediments. The canopies of these
organisms disperse wave energy, while their high burial rates elevate the seafloor, mitigating
the effects of increasing sea levels and wave activity linked to climate change. The reduction
of one-third of the worldwide extent of these ecosystems results in the loss of carbon dioxide
(CO2) absorption areas and the release of 1 petagram (Pg) of CO 2 per year. Utilising
vegetated coastal habitats in eco-engineering solutions for coastal protection is a potential
technique for climate change mitigation and adaptation, as it offers great capacity for
conservation, restoration, and usage (Duarte, Carlos M. et al., 2013). Approximately 60% of
the human population residing in coastal areas utilise the resources found along the shore
(Kathiresan and Rajendran, 1996). Mangrove, seagrass, and coral reef ecosystems are
prevalent coastal and estuary habitats that are commonly found in tropical and subtropical
latitudes. These ecosystems serve as homes, protection, and sources of nourishment for
various organisms, including certain species that are crucial for supporting important fisheries
near the shore (Little et al., 1988; Van der Velde et al., 1995; Pinto and Punchihewa, 1996,
Springer and McErlean, 1962; Austin, 1971; Weinstein and Heck, 1979; Thayer et al., 1987;
Baelde, 1990; Sedberry and Carter, 1993, Blaber, 1980; Bell et al., 1984; Robertson and
Duke, 1987; Blaber and Milton, 1990; Morton, 1990; Tzeng and Wang, 1992). The interplay
between sea grass, coral reefs, and near-shore fisheries is frequently cited as a reason to
protect and sustainably utilise mangroves. According to Alongi (2002), almost 30 percent of
the world's mangrove cover has been lost in the last 50 years. A significant portion of this
decline has taken place in the Asian area. The decrease in capture fisheries productivity is
worrisome since it is considered the primary source of value for sold items and a foundation
for subsistence fishing in undamaged mangrove forests.
1.3 Statement of the Research Problem
The present research focused on the micro-zoning of the mangrove-dominated coastal
ecosystem of a particular island group in the Andaman archipelago and the suitability
mapping of this specific ecosystem. This work emphasizes the coastal mangroves and, will be
beneficiary for society not only the people who live in the coastal region but also the entire
socio-ecological environment of the region. Mangroves protect coastal regions from natural
hazards like storms, tidal damage, and floods. Moreover, it helps to maintain the clarity of
seawater and its quality. But nowadays overgrowth of populations, development of port
regions, over-harvesting of marine resources are major threats to mangroves and associated
communities. The proposed ecosystem-based health assessment will help to monitor the
health of the mangroves and associated communities and policy formulation for a healthy
future for these communities. On the other coral works as a natural protector of the shoreline.
In the study area, it is seen that mangroves, seagrass, and coral are sited together, so these
symbiotic ecosystems protect themselves vis-a-vis the shoreline. However, it is reported that
after the 2004 devastating tsunami, many of the mangrove regions are under threat. The
tsunami caused 20% of mangrove degradation in the Andaman group. Apart from natural
calamities North & Middle Andaman are the major tourist spots and district important
locations of Andaman. The fishery industry also depends upon the three couple ecosystems
(Mangrove-Seagrass-Coral) because it gives shelter to many sea fishes. But sometimes over-
fishery and over-tourist strength causes major harm to couple ecosystems. So, the work will
try to find the key factors that are responsible for the degradation of mangroves and link the
future livelihood pattern using a multi-criteria decision support system. The outcome will
help to prepare the implementable natural resource conservation plan of the region. In
conclusion, it must be said that the work will help to prepare the core relation of mangrove-
coastal livelihood and the future of mangrove-coastal livelihood-livelihood pattern which can
help take necessary steps for local government for the community conservation and provide
the sustainable development plan of these communities which will help to enrich local
tourism, beneficiary for medical research as well as all over economic enrichment.
1.4 Objective of the Thesis
The mangrove-dependent socio-ecological system (SES) of north Andaman has changed
due to the impact of extreme events and anthropogenic interventions. Keeping the view in
mind of the above, the present work would address the four major objectives.
1. Identify and estimate the changes in the mangrove ecosystem.
2. Understand the trends of land use/land cover in mangrove fringe villages.
3. Understand the pattern and trends in Mangrove-dominated SES.
4. Address the SES changes to promote sustainable development.
1.5 Scope and Limitation of the Study
Scope of the study
This study may be conceived as a pioneering effort, wherein a hybrid methodology
integrating geospatial with ethnographic research methods techniques was adopted for
assessing the socio-ecological relationship of the mangrove-dependent coastal starch of North
Andaman, India.
Given the above statement, the study will also elaborate.
i. Detail the status of community-level (Fishing) socio-ecological relationship of North
Andaman
ii. Understand the key problems of community-level (Fishing) socio-ecological systems.
iii. Address the key problems via an appropriate framework to manage the issues in a
sustainable manner.
Limitation of the Study
a. Application of satellite datasets for assessing long-term spatiotemporal dynamics of
the mangrove ecosystem and LULC as found in this study with anomalous spatial
resolution and gap in the period due to the unavailability of fine-resolution historical
images in open-source domains.
b. The study only considered the mangrove ecosystem among the wide range of coastal
ecosystems based on the direct relationship of mangroves and fishing communities.
c. The western side of the Diglipur region was not considered for field verification
(Land use/land cover verification, mangrove health status verification) due to its
inaccessible nature.
1.6 Contribution of the Present Study
The study will generate a general understanding of the region at a minute level, which
helps the academicians, researchers, and policymakers to extend their knowledge about the
status of an ecosystem, its change pattern, the socio-ecological relationship, and sustainable
management aspects of the Diglipur region. It will illustrate a basic framework to the regional
planners and managers for sustainable land-use planning, especially an emphasis on
mangrove socio-ecology. Local stakeholders will get a real idea about how the mangrove is
changing rapidly, the present status of land use, and what will be the future mangrove status
along with risk factors in the coming decades. The outcomes will also guide all levels of
stakeholders to understand the complexities of the present scenario, the inherent resilience
factors, community aspirations, and the possible leverage points to solve the problem
sustainably using the unique resilience framework named Wayfinder. This is a new approach
presented through this study which aimed to promote sustainable development and a healthy
socio-ecological relationship over the region.
1.7 Research Hypothesis
Given the present research gaps, problems, objectives, and preliminary field
observations the hypothesis of the present research could be stated as
“The socio-ecological relationship of mangrove-dependent communities is in crisis
which can be reduced to a greater extent via sustainable development initiatives.”
1.8 Structure of the Thesis
The present dissertation has been detailed in six chapters to achieve the outcome.
Chapter 1: This chapter encompassed a general overview of the topic, the scope of the work
with limitations, objectives how this research contributes to society.
Chapter 2: The literature review is one of the important sections to understand the research
trends and research gaps. In this section, peer reviewed publications have been studied to find
out the potential gap. This extensive study also helps to format the research scope which was
poorly explored in the past days.
Chapter 3: Detailed information about the study location has been noted in this section. The
overview of various methods and the use of multidimensional data with their source has been
detailed in this section. Hence, the detailed methodology is elaborated in a separate section of
the further chapter.
Chapter 4: Studying mangrove vegetation dynamics using geospatial techniques along with
estimation of net primary productivity, vegetation indices and future aerial coverage in
different climatic sceneries are the key aspects of this chapter.
Chapter 5: Mangroves are depleting day by day. In this connection, the status of the socio-
ecological relationship of mangrove-dependent coastal communities, especially the fisherman
community, is expressed via participatory analysis and ethnographic research. Finally, the
implications of changing relations are addressed using the resilience model to help
policymakers take possible sustainable development initiatives.
Chapter 6: Finally, the concluding statement has been further investigated to promote
sustainable development.
