Ecosystem Services of Mangroves - A Systematic Review and Synthesis of Contemporary Scientific Literature
Ecosystem Services of Mangroves - A Systematic Review and Synthesis of Contemporary Scientific Literature
Ecosystem Services of Mangroves - A Systematic Review and Synthesis of Contemporary Scientific Literature
Review
Ecosystem Services of Mangroves: A Systematic Review and
Synthesis of Contemporary Scientific Literature
Kanika Bimrah 1,2 , Rajarshi Dasgupta 2, * , Shizuka Hashimoto 2,3 , Izuru Saizen 1 and Shalini Dhyani 4
1 Laboratory of Regional Planning, Graduate School of Global Environmental Studies, Kyoto University,
Kyoto 615-8501, Japan
2 Integrated Sustainability Centre (ISC), Institute of Global Environmental Strategies, Hayama 240-0015, Japan
3 Laboratory of Landscape Ecology and Planning, Department of Ecosystem Studies, The University of Tokyo,
Tokyo 113-8657, Japan
4 National Environmental Engineering Research Institute, Nagpur 440 020, India
* Correspondence: dasgupta@iges.or.jp
Abstract: The paper narrates a systematic literature review on ‘’mangrove ecosystem services” to
identify their typology, distribution, and utilization within the contemporary scientific literature.
We performed a systematic review of 76 research articles derived from the Scopus database, and
the dataset was scrutinized and classified against the four major categories of ecosystem services,
namely provisioning, regulating, cultural, and supporting services, as per the Millennium Ecosystem
Assessment (2005). We attempted to determine the existing state of the interconnectedness of
mangrove ecosystem services by mapping the potential synergies and trade-offs. Further, an attempt
was made to understand the critical linkages between mangrove ecosystem services and their
contribution to the localization/achievement of the Sustainable Development Goals (SDGs). The
results suggest disproportionate distribution of scientific literature, where nearly 56 of the studies
were concentrated in Asia. The recognition of regulating the services of mangroves, particularly in
Citation: Bimrah, K.; Dasgupta, R.; carbon storage and disaster risk reduction, outnumbered the other types of ecosystem services. In
Hashimoto, S.; Saizen, I.; Dhyani, S. particular, studies related to mangroves’ cultural ecosystem services remain underrepresented. The
Ecosystem Services of Mangroves: A results show a strong correlation in terms of synergies between the coastal protection ecosystem
Systematic Review and Synthesis of services and the high carbon sequestration ability of mangroves; and the trade-off between facilitating
Contemporary Scientific Literature. water transport services and the provision of fresh water. Of the 17 SDGs, three SDGs, namely, SDG
Sustainability 2022, 14, 12051.
12 (responsible consumption and production), SDG 13 (climate action), and SDG 14 and 15 (life below
https://doi.org/10.3390/
water and life on land) showed close interrelationships with the existing database. As such, the
su141912051
results are beneficial for coastal planners to better integrate and mainstream mangrove ecosystem
Academic Editor: Pablo Peri services into coastal and regional planning, by maximizing synergies, encouraging the involvement
Received: 26 August 2022
of coastal communities as well as elaborating ameliorative adaptive measures.
Accepted: 19 September 2022
Published: 23 September 2022 Keywords: mangroves; ecosystem services; synergies and trade-off; Sustainable Development Goals
(SDGs); bibliometric analysis
Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
iations.
1. Introduction
Mangroves provide an extensive array of ecosystem services that are indispensable to
human well-being, particularly in the low-lying coastal areas of developing economies [1–4].
Copyright: © 2022 by the authors. They serve as the breeding ground for aquatic fauna and an accumulation site for sed-
Licensee MDPI, Basel, Switzerland. iments and nutrients [5–7]. Additionally, they play a significant role in climate change
This article is an open access article adaptation and disaster risk reduction [8–12]. For instance, mangroves offer invaluable
distributed under the terms and protection during typhoons and storm surges [13,14], and help in nutrient cycling and
conditions of the Creative Commons retention [15,16], and have the highest rate of carbon sequestration per area of habitat which
Attribution (CC BY) license (https:// is approximately ten times of the terrestrial ecosystems [4,17]. Such an exceptional ability
creativecommons.org/licenses/by/
to capture carbon brings them to the centre of the ongoing advocacy of Ecosystem-based
4.0/).
mitigation and adaptation; strategies that help to harness nature and ecosystem services
for a climate-resilient future [15,18,19].
Mangroves also offer several livelihood opportunities to local communities through the
provisioning of fish, crabs, honey, nipa leaves, timber, fuel, and medical resources. [11,20].
These ecosystem services, such as fisheries, timber products, tourism, etc., add to the
direct economic benefit of local populations in terms of income sources [21–23]. It has
been estimated that the economic value of mangrove habitats ranges from USD 2772 per
hectare/year up to as much as USD 80,334 per hectare/year, with an average of USD
28,662 per hectare/year [24–26]. However, owing to various anthropogenic pressures,
such as coastal development, industrialization, deforestation of mangroves for palm oil
plantations, expansion of rice paddies, expansion of shrimp farms for aquaculture, and
environmental pollution, these coastal ecosystems are degrading at a significant pace.
Between 2000 and 2010, the global losses of functioning coastal ecosystems were estimated
to be approximately 1 to 2% every year [27–29]. However, recent estimates on global
mangrove deforestation highlighted an annual loss of between 0.26 and 0.66/year, which is
significantly lower than the previous estimates [28,29].
The concept of Ecosystem Services
To strengthen the fundamental association between human society and ecosystems,
The Millennium Ecosystem Assessment has advanced the concept of ecosystem services
since 2005. It provided a valuable framework for analysing ecosystem services and classi-
fied them into four utility classes, namely ‘provisioning’ (e.g., food and fibre, fuel, wood,
construction materials, wood, medical resources), ‘supporting’ (e.g., nutrient cycling, soil
formation, primary production, maintenance of genetic diversity), ‘regulating’ (e.g., climate
regulation, flood and storm protection, erosion prevention) and ‘cultural’ (e.g., recreation,
tourism, psychological benefits) services [11,20,23,30]. Over the past several years, re-
searchers have extensively used this framework to assess and model mangrove ecosystem
services across the world [11,31–33]. In general, these studies have argued for the conser-
vation benefits of mangroves ecosystems as compared to the alternative uses [21,34,35].
To strengthen mangrove conservation policies, some recent studies have further analysed
the inter-linkages of the role of mangroves and Sustainable Development Goals (SDGs) to
quantify the contribution of mangroves in the global sustainability agenda [31,36–38].
Despite a plethora of research on mangrove ecosystem services, there is still a lack of
integration studies, which provide a synoptic overview of the ecosystem services provided
by mangrove ecosystems. Earlier, some studies mentioned that mangroves provide more
than 70 ecosystem benefits/service [39]; however, to the best of our knowledge, studies
that substantiate such claims from a global research perspective are not readily available. In
other words, although the policy planners are now aware of the immense benefits provided
by mangroves, there is a dearth of information that characterizes the nature and typology of
mangrove ecosystem services, for example, which ecosystem services are appreciated most,
what are the common synergies and trade-offs, etc. Such an understanding of the inter-
relationship of mangrove ecosystem services, i.e., the synergies and trade-offs between
the different categories of mangrove ecosystem services, remains crucial for informed
decision-making for coastal zone conservation, particularly at the local scale.
In this study, we aim to provide a synoptic overview of the current state of knowledge
on mangrove ecosystem services as revealed in the contemporary scientific literature.
Through a systematic literature review, we aim to answer the following research questions,
namely (1) what are the different types of ecosystem services provided by mangroves,
and how these are reflected in the contemporary scientific literature? (2) how do the
mangrove ecosystem services contribute to the localization of Sustainable Development
Goals (SDGs)? Lastly, (3) what are the synergies and trade-offs in the different categories of
mangrove ecosystem services? Based on a systematic literature review, combined with a
citation network and correlation analysis; we aim to elaborate on the current knowledge
of mangrove ecosystem services and their utilization from the contemporary scientific
literature. The study provides a comprehensive overview of the mangrove ecosystem
Sustainability 2022, 14, x FOR PEER REVIEW 3 of 17
Sustainability 2022, 14, 12051 knowledge of mangrove ecosystem services and their utilization from the contemporary 3 of 16
scientific literature. The study provides a comprehensive overview of the mangrove eco-
system services, by elucidating the interlinkages between different categories of ecosys-
tem services
services, and mapping
by elucidating the research trends
the interlinkages ondifferent
between the observed inter-disciplinarily
categories within
of ecosystem services
the scientific research on mangroves.
and mapping the research trends on the observed inter-disciplinarily within the scientific
research on mangroves.
2. Materials and Methods
2. Materials
2.1. and Methods
Data Collection and Dataset Preparation
2.1. Data Collection and Dataset
For this analysis, we Preparation
followed the Preferred Reporting Items for Systematic Reviews
and For this analysis,(PRISMA)
Meta-Analyses we followed the Preferred
guidelines Reporting
to document Items forliterature
systematic Systematic Reviews
reviews as
and
shownMeta-Analyses
in Figure 1. We (PRISMA)
performed guidelines
a systematicto document systematic
literature review usingliterature
the Scopus reviews
databaseas
shown in Figure 1. We performed
(https://www.scopus.com/, a systematic
assessed on 8 Aprilliterature
2021) to review using theliterature
collect existing Scopus database
on man-
(https://www.scopus.com/, assessed on 8 April 2021) to collect
grove ecosystem services. The keywords used for the search query were in the existing literature
order, KEYon
mangrove ecosystem services. The keywords used for the search
(mangroves) AND KEY (ecosystem AND services) AND KEY (assessment) OR KEY (mon- query were in the order,
KEY (mangroves)
itoring) AND KEY (ecosystem
OR KEY (modelling). ConsideringAND services)
that the concept AND KEY (assessment)
of ecosystem OR KEY
services emerged
(monitoring) OR KEY (modelling). Considering that the concept of
in the first half of 2000 and became popular after the publication of the Millennium ecosystem services
Eco-
emerged in the first half of 2000 and became popular after the publication
system Assessment (2005), the search was limited to publications in the English language, of the Millen-
nium
whichEcosystem Assessment
were published in and (2005), the search
after 2000. The fullwas textlimited to publications
of all articles in thefrom
was retrieved English
the
language, which were published in and after 2000. The full text of all articles
Scopus database using the defined search criteria (n = 90) and these articles were manually was retrieved
from the Scopus
screened. database
Articles using any
not meeting the defined search criteria
of the screening (n =
criteria 90) and
were these articles
excluded were
from further
manually
analysis, i.e., (1) articles, which were not available or accessible, (2) articles, which from
screened. Articles not meeting any of the screening criteria were excluded were
further analysis, i.e., (1) articles, which were not available or accessible, (2) articles, which
not relevant to the research questions, i.e., did not articulate any specific ecosystem ser-
were not relevant to the research questions, i.e., did not articulate any specific ecosystem
vices. After the manual screening, 76 articles fulfilled the criteria, which were considered
services. After the manual screening, 76 articles fulfilled the criteria, which were considered
for further analysis.
for further analysis.
Figure 1.
Figure 1. Methodology
Methodology and
and search
search criteria
criteria used
used in
in systematic
systematic literature
literature review
review for
for identification
identification of
of
research articles.
research articles.
different types of mangrove ecosystem services. They were organized into four cate-
gories based on the ecosystem services classification framework of Millennium Ecosystem
Assessment (2005), namely provisioning, regulating, supporting, and cultural services. Ad-
ditionally, we evaluated the direct and indirect linkages between the mangrove ecosystem
services and SDGs. Due to the complex dimensionality of interactions between ecosystem
services and SDGs when viewed socially, economically, and environmentally, we used a
thematic segregation framework based on the criteria specified in Table 1. Nonetheless,
these subjective classifications might vary a little according to the location and extent of
mangrove forests and their underlying relationship with the local communities.
The relative geographic distribution of sites mentioned in research studies was clas-
sified according to the countries of origin. Lastly, the mangrove extent base map was
retrieved from the World Atlas of Mangroves (Ocean Data Viewer, 2018) and we used QGIS
(3.16 Hannover) to plot the existing studies onto the base map.
Bibliometric network analysis was performed using VosViewerTM software (Version
1.6.16) for the creation, visualization, and exploration of maps based on the bibliometric
network data. From the Scopus search results, we created two types of maps based on
(1) the co-occurrence of keywords represented through network visualization and (2) its
relationship to yearly trends, which is represented through overlay visualization. The
‘Full counting method’ was used and the minimum number of occurrences was set to
five [40–42]. Based on the above criteria, out of 1549 keywords that were identified from
the database, 78 keywords met the threshold. Each network map that was generated from
the analysis contains nodes, i.e., keywords with varying sizes that determine the ‘total
link strength’ and the thickness of the lines connecting these nodes was based on the
‘link strength’.
Lastly, to identify the correlation between categories of mangrove ecosystem ser-
vices, we conducted a Spearman’s rank correlation test using IBM SPSSTM (Version 28.0).
Spearman’s Correlation Coefficient for non-parametric correlations was calculated after
Sustainability 2022, 14, 12051 5 of 16
appropriate conversion of data into an ordinal form, wherein the correlation was considered
significant at 0.05 level (2 tailed) and 0.01 level (2 tailed).
Table 2. Frequency of research studies that developed for mangrove ecosystem services for each ecosystem service category over time. (Note: Colour represents the
number of research studies).
Classification 2001 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 Total
S1. Nutrient cycling 18
S2. Nursery and breeding ground 24
Supporting S3. Biomass production 9
S4. Habitat (Terrestrial and marine fauna) 23
S5. Reducing Eutrophication 2
P1. Food Products 16
P2. Fuel Wood 14
P3. Timber Products 17
P4. Charcoal Production 6
Provisioning P5. Medicines 6
P6. Fresh Water 1
P7. Fishing and Aquaculture practices 17
P8. Water Transport 3
P9. Construction Materials 3
R1. Climate Regulation and mitigation 10
R2. Coastal protection 25
R3. Sequester and store carbon 33
Regulating R4. Flood protection 14
R5. Storm protection 24
R6. Wastewater bioremediation 14
R7. Prevention of saltwater intrusion 4
C1. Tourism or Eco-Tourism 15
C2. Nature-based Recreation 12
Cultural C3. Aesthetic value 7
C4. Cultural Amenities 4
C5. Education 4
Total 6 8 4 3 3 19 13 23 29 55 18 28 32 39 29 16 325
Number of research studies 1 2 3 4 5
Sustainability 2022, 14, 12051 7 of 16
After elucidating the relative geographic distribution with a focus on mangrove ecosys-
tem services, as shown in Table 3, it was found that the majority of research studies have
been carried out in Asia (n = 34) and have focused on regulating ecosystem services. The
high number of studies from Asia generally corresponds to the global distribution of
mangroves as Asia enjoys nearly 40% of the mangrove extent. In addition, the volumi-
nous literature on the mangrove ecosystems of Asia substantiates the strong concern of
researchers and policymakers to study the protective nature of mangrove forests against
the catastrophic effects of coastal risks and hazards [47]. Furthermore, Southeast Asia is the
epicentre of anthropogenic mangrove deforestation, and a lot of its mangrove ecosystems
are estimated to be severely impacted by sea-level rise over the next century [48]. Con-
cerning the regional distribution of research studies, 20 per cent (n = 15) did not mention
any specific region. The geographic distribution of the remaining 80 per cent (n = 61) of
research studies plotted on a world map shown in Figure 2 reflects in general, 56 per cent
(n = 34) of research studies concentrated in Asia. This is justifiable because approximately
40 per cent of the world’s mangrove forests exists in Asia [49].
Types of ESs
Number of Supporting Provisioning Regulating Cultural
Continent
Research Studies
Number Percent Number Percent Number Percent Number Percent
Asia 34 24 39% 21 34% 24 39% 15 25%
Africa 6 3 5% 3 5% 5 8% 0 0%
South America 4 2 3% 1 2% 4 7% 1 2%
North America 10 7 11% 3 5% 8 13% 5 8%
Australia 5 2 3% 2 3% 5 8% 1 2%
Sustainability
Europe 2022, 14, x FOR PEER
1 REVIEW 0 0% 0 0% 1 2% 0 80%
of 17
Multi-regional 1 0 0% 0 0% 1 2% 0 0%
Figure2.2.Geographic
Figure Geographicdistribution
distribution of
of study
study sites
sites mentioned in research studies.
studies.
3.2.
3.2.Contribution
ContributionofofMangrove
Mangrove Ecosystem
Ecosystem Services
Services for
for Localized Implementation of
Localized Implementation of SDGs
SDGs
WeWeidentified
identifiedthethelinkages
linkages between
between mangrove
mangrove ecosystem services and
ecosystem services and the
the1717SDGs
SDGs
using
using a quasi-quantitative approach, using the general assumption specified in Table 1.1.
a quasi-quantitative approach, using the general assumption specified in Table
Undeniably,
Undeniably,thethe SDGs haveencouraged
SDGs have encouragedcountries
countries across
across thethe world
world to achieve
to achieve a better
a better and
and more sustainable future. Biospeheric goals are relevant because economic,
more sustainable future. Biospeheric goals are relevant because economic, resilience andresilience
global peace relies on them. Overall, the mangrove ecosystem services contribute to 13
SDGs, but disproportionately. In particular, SDGs that exhibit close interrelationships
with mangrove ecosystem services were SDG 12 (responsible consumption and produc-
tion), SDG 13 (climate action), SDG 14 (life below water) [insufficient publications] and
SDG 15 (life on land), as shown in Figure 3 (see the Table S1 in Supplementary file). For
Sustainability 2022, 14, 12051 8 of 16
and global peace relies on them. Overall, the mangrove ecosystem services contribute to
13 SDGs, but disproportionately. In particular, SDGs that exhibit close interrelationships
with mangrove ecosystem services were SDG 12 (responsible consumption and production),
SDG 13 (climate action), SDG 14 (life below water) [insufficient publications] and SDG 15
(life on land), as shown in Figure 3 (see the Table S1 in Supplementary file). For instance,
Sustainability 2022, 14, x FOR a
PEER REVIEW
good number of research studies (n = 30) have discussed the important role 9 of 17
mangrove
ecosystems play in climate change adaptation and mitigation, which corresponds to SDG
13, because of their adaptive capacity to climate-related hazards and natural disasters.
leading to enhanced destruction that enhances the intensity of damage due to extreme
Mangrove forests are extremely efficient at carbon sequestration; protecting them is critical
climate events and sea level rise. Nonetheless, our findings also have a significant associ-
to mitigating climate change. In ongoing international climate discussions conserving
ation with SDG 14 (life below water). However, the current ecosystem studies primarily
existing naturaltoforests
contribute including
the localized mangrovesofhave
implementation threereceived immense
SDGs, namely SDG 12recognition
(responsibleto address
the Nationally
consumptionDetermined Contributions
and production), 13 (climate(NDCs) hence,
action), and protecting
15 (life on land) and restoring
and have so farthem can
help address global
ignored or have climate as well
insufficiently as restoration
assessed the impact targets and promises
of mangrove ecosystem including
services onthe Bonn
other pertinent
Challenge for ForestSDGs.
Landscape Restoration (FLR) and the UN Decade on Restoration, 2021.
3. Research
FigureFigure studies
3. Research that
studies thatdemonstrated linkages
demonstrated linkages withwith Sustainable
Sustainable Development
Development Goals (SDGs)
Goals (SDGs)
over time.
over time.
3.3. Bibliometric Analysis and Correlation between the Categories of Mangrove Ecosystem Ser-
Further, in the context of SDG 15, some research studies (n = 27) mentioned that the
vices
degradation of mangrove ecosystems is largely driven by anthropogenic activities, such
As shown in the network visualization diagram (Figure 4), ‘mangrove’ had the high-
as coastal development, deforestation for agriculture activities, and the wide expansion
est occurrences (n = 82) and maximum total link strength, i.e., 757 followed by ‘ecosystem
of aquaculture practices.63,Lastly,
services’ (occurrence: another
link strength: good
581) number of(occurrence:
and ‘ecosystem’ research studies (n = 20) demon-
37, link strength:
strated
387). Additionally, an overlay visualization map was created to understand the yearlyactivities,
that a strong relationship exists between coastal economic development
such as port and jetty, chemical factories, thermal power projects, intensive shrimp aqua-
Sustainability 2022, 14, 12051 9 of 16
culture, palm oil plantation, which is responsible for almost 35% of the total mangrove
loss [50,51], that is against SDG 12, which aims at sustainable consumption and production
patterns, especially target 12.1, i.e., sustainable management and efficient use of natural
resources. For example, the vast expansion of aquaculture practices for the livelihood and
income of local communities more or often compromises the delivery of diverse mangrove
ecosystem services. Similarly, large scale coastal development for national or corporate
interest comes at expensive cost of mangrove degradation and land use changes leading
to enhanced destruction that enhances the intensity of damage due to extreme climate
events and sea level rise. Nonetheless, our findings also have a significant association with
SDG 14 (life below water). However, the current ecosystem studies primarily contribute
to the localized implementation of three SDGs, namely SDG 12 (responsible consumption
and production), 13 (climate action), and 15 (life on land) and have so far ignored or have
insufficiently assessed the impact of mangrove ecosystem services on other pertinent SDGs.
3.3. Bibliometric Analysis and Correlation between the Categories of Mangrove Ecosystem Services
Sustainability 2022, 14, x FOR PEER REVIEWAs shown in the network visualization diagram (Figure 4), ‘mangrove’ had the
10 highest
of 17
occurrences (n = 82) and maximum total link strength, i.e., 757 followed by ‘ecosystem
services’ (occurrence: 63, link strength: 581) and ‘ecosystem’ (occurrence: 37, link strength:
387). Additionally, an overlay visualization map was created to understand the yearly
trend of these linkages, as shown in Figure 5. The overlay visualization superimposes time
trend of these linkages, as shown in Figure 5. The overlay visualization superimposes
on the keyword co-occurrence network wherein the different colours correspond to the
time on the keyword co-occurrence network wherein the different colours correspond to
year in which the keyword appears the maximum number of times. The keywords “car-
the year in which the keyword appears the maximum number of times. The keywords
bon”, “forestry”, “remote sensing”, “carbon sequestration”, etc., were focused on the re-
“carbon”, “forestry”, “remote sensing”, “carbon sequestration”, etc., were focused on the
search studies as late as the year 2017. In contrast, certain keywords e.g., “climate change”,
research studies as late as the year 2017. In contrast, certain keywords e.g., “climate change”,
“aquaculture”, “coastal zone”, etc., mainly appeared in 2014.
“aquaculture”, “coastal zone”, etc., mainly appeared in 2014.
Figure
Figure 4.4.Network visualization
Network denoting
visualization the keywords,
denoting whichwhich
the keywords, have highest numbernumber
have highest of co-occur-
of co-
rences through
occurrences nodes,nodes,
through and line
andwidth connecting
line width these nodes
connecting varies varies
these nodes according to link to
according strength.
link strength.
The Venn diagram shown in Figure 6 demonstrates overlaps between the categories of
ecosystem services. It was evident that numerous research studies discussed more than
one category of ecosystem services (see Tables S2 and S3 in the Supplementary Material).
As such, researchers have evaluated regulating ES (n = 62) more as compared to supporting
ES (n = 52) or provisioning ES (n = 37) or cultural ES (n = 24). It can also be observed that
the research studies which mention supporting and regulating ecosystem services have a
maximum intersection (n = 42) and maximum number (n = 12) of research studies have
exclusively discussed regulating ecosystem services.
Sustainability 2022, 14, 12051 Figure 4. Network visualization denoting the keywords, which have highest number of co-occur- 10 of 16
rences through nodes, and line width connecting these nodes varies according to link strength.
The Venn diagram shown in Figure 6 demonstrates overlaps between the categories
of ecosystem services. It was evident that numerous research studies discussed more than
one category of ecosystem services (see appendixes 2 and 3 in the Supplementary Mate-
rial). As such, researchers have evaluated regulating ES (n = 62) more as compared to
All
All combined,
combined, the the research
research studies
studiesreported
reportedaatotal totalofof325
325individual
individual ecosystem
ecosystem ser-
services
vices (n = 325) (e.g., if a study discussed three types of regulating
(n = 325) (e.g., if a study discussed three types of regulating ecosystem services and two ecosystem services and
two
types types of provisioning
of provisioning ES, ES,
thenthen
we we counted
counted it as
it as fivefive ecosystem
ecosystem services).The
services). Thenumber
numberof
of research
research studies
studies thatthat mention
mention eacheach sub-category
sub-category of mangrove
of mangrove ecosystem
ecosystem services
services is shownis
shown in Table 2. To have an in-depth understanding of the
in Table 2. To have an in-depth understanding of the degree of relationship between thedegree of relationship be-
tween the sub-categories
sub-categories of mangrove of mangrove
ecosystemecosystem services, Spearman’s
services, Spearman’s correlationcorrelation
coefficientcoeffi-
(r) was
cient (r) was calculated as shown in Table 4. The correlations
calculated as shown in Table 4. The correlations were evaluated based on the were evaluated based ontrade-
likely the
likely trade-offs and synergy among the ecosystem services across
offs and synergy among the ecosystem services across the sub-category level. The trade-off the sub-category level.
The
can trade-off
be defined canasbea defined
situationaswhen
a situation when
the uses of the
oneuses of one ES
ES directly or directly
indirectlyor indirectly
decrease or
decrease
affects another ES, whereas synergy is a situation when the use of one ESofisone
or affects another ES, whereas synergy is a situation when the use ES is
increasing
increasing
the benefitsthe ofbenefits
anotherof ESanother
[33]. InES [33].
this In this
case, case, a correlation
a negative negative correlation
between two between two
ecosystem
ecosystem services demonstrates
services demonstrates a trade-off
a trade-off scenario and ascenario
positive and a positive
correlation correlation
demonstrates demon-
a synergistic
strates a synergistic
relationship between relationship between the
the two ecosystem two ecosystem
services. The two services. The two
sub-categories of sub-cate-
regulation
gories of regulation ecosystem services, i.e., coastal protection (R2)
ecosystem services, i.e., coastal protection (R2) and sequestration and storage of carbon and sequestration and
(R3)
storage of carbon (R3) exhibited the strongest positive correlation
exhibited the strongest positive correlation (r = 0.963) whereas freshwater (P6) and water (r = 0.963) whereas
freshwater
transport (P8) (P6)demonstrated
and water transport (P8) demonstrated
the strongest negative correlationthe strongest negative
(r = −0.400). The correlation
first case can
(r = −0.400). The first case can be explained as the case of co-benefits,
be explained as the case of co-benefits, e.g., a healthy vegetation offers best protection e.g., a healthy vege- while
tation offers best
also supports protection
carbon while also supports carbon sequestration.
sequestration.
Sustainability 2022, 14, 12051 11 of 16
Table 4. Spearman correlation coefficient showing degree of relationship between mangroves ecosystem services.
Wastewater Bioremediation
Sequester and Store Carbon
Reducing Eutrophication
Nature-based Recreation
Tourism or Eco-Tourism
Water Transport (Ports)
Construction Materials
Biomass Production
Charcoal Production
Cultural Amenities
Coastal Protection
Nutrient Cycling
Storm Protection
Timber Products
Flood Protection
Aesthetic Value
Food Products
Fresh Water
Education
Fuel Wood
Medicines
S1 S2 S3 S4 S5 P1 P2 P3 P4 P5 P6 P7 P8 P9 R1 R2 R3 R4 R5 R6 R7 C1 C2 C3 C4 C5
S1
0.661
S2
**
0.543 0.616
S3
** **
0.743 0.934 0.560
S4
** ** **
S5 0.175 −0.261 −0.148 −0.174
0.634 0.833 0.548 0.752
P1 −0.223
** ** ** **
0.617 0.744 0.753 0.768
P2 0.155 −0.253
** ** ** **
0.717 0.871 0.476 0.828 0.872 0.893
P3 −0.281
** ** * ** ** **
0.489 0.611 0.572 0.543 0.824 0.799
P4 0.045 −0.238
* ** ** ** ** **
0.566 0.393 0.489 0.583 0.638 0.504 0.415
P5 0.158 −0.158
** * * ** ** ** *
P6 0.029 0.107 −0.218 0.100 −0.123 0.207 0.366 0.172 0.198 0.145
0.803 0.765 0.634 0.857 0.663 0.550 0.653 0.671
P7 −0.117 0.362 −0.036
** ** ** ** ** ** ** **
0.489 −0.400 0.563
P8 0.356 0.165 0.275 −0.174 0.103 −0.087 0.071 −0.175 0.378
* * **
0.557 0.491 0.411 0.628 0.527
P9 0.110 −0.272 0.370 0.165 0.002 0.162 0.160 −0.145
** * * ** **
Sustainability 2022, 14, 12051 12 of 16
Table 4. Cont.
Wastewater Bioremediation
Sequester and Store Carbon
Reducing Eutrophication
Nature-based Recreation
Tourism or Eco-Tourism
Water Transport (Ports)
Construction Materials
Biomass Production
Charcoal Production
Cultural Amenities
Coastal Protection
Nutrient Cycling
Storm Protection
Timber Products
Flood Protection
Aesthetic Value
Food Products
Fresh Water
Education
Fuel Wood
Medicines
0.870 0.595 0.722 0.564 0.691 0.726 0.601 0.678 0.757 0.443
R1 0.373 −0.097 −0.036 −0.005
** ** ** ** ** ** ** ** ** *
0.746 0.899 0.761 0.878 0.815 0.599 0.767 0.502 0.891 0.422 0.511 0.629
R2 −0.242 0.353 0.050
** ** ** ** ** ** ** ** ** * ** **
0.656 0.860 0.783 0.813 0.744 0.491 0.679 0.446 0.861 0.463 0.481 0.520 0.963
R3 −0.281 0.293 0.000
** ** ** ** ** * ** * ** * * ** **
0.711 0.921 0.601 0.859 0.818 0.744 0.912 0.629 0.659 0.561 0.693 0.825 0.768
R4 −0.243 0.333 0.072 0.210
** ** ** ** ** ** ** ** ** ** ** ** **
0.611 0.914 0.767 0.823 0.838 0.595 0.831 0.447 0.632 0.739 0.492 0.857 0.821 0.917
R5 −0.222 0.215 0.050 0.145
** ** ** ** ** ** ** * ** ** * ** ** **
0.897 0.728 0.696 0.753 0.746 0.552 0.761 0.477 0.522 0.831 0.458 0.821 0.802 0.730 0.770 0.726
R6 −0.010 −0.129 0.226
** ** ** ** ** ** ** * ** ** * ** ** ** ** **
0.642 0.622 0.450 0.620 0.637 0.595 0.571 0.399 0.688 0.601
R7 0.284 0.128 −0.199 0.043 0.081 0.243 −0.136 0.350 0.347 0.294
** ** * ** ** ** ** * ** **
0.669 0.767 0.808 0.687 0.746 0.413 0.649 0.474 0.804 0.568 0.410 0.568 0.891 0.919 0.743 0.771 0.817
C1 −0.263 0.270 −0.130 0.256
** ** ** ** ** * ** * ** ** * ** ** ** ** ** **
0.838 0.668 0.765 0.616 0.709 0.722 0.627 0.682 0.780 0.390 0.931 0.663 0.588 0.715 0.535 0.810 0.481 0.604
C2 0.349 −0.098 0.036 0.080
** ** ** ** ** ** ** ** ** * ** ** ** ** ** ** * **
0.510 0.597 0.706 0.530 0.496 0.507 0.568 0.735 0.438 0.660 0.571 0.570 0.494 0.508 0.474 0.473 0.778
C3 0.252 −0.286 0.377 −0.102 −0.005 0.348
** ** ** ** * ** ** ** * ** ** ** * ** * * **
0.439 0.420 0.459 0.653 0.508 0.412 0.501 0.623 0.554
C4 0.311 0.294 −0.212 0.102 0.302 0.385 0.321 0.129 −0.193 0.318 0.029 0.284 0.231 0.313 0.256
* * * ** ** * ** ** **
0.699 0.502 0.519 0.496 0.543 0.682
C5 0.319 0.085 0.080 0.199 −0.218 0.086 0.233 0.112 0.193 −0.176 −0.379 0.214 0.228 0.006 −0.131 0.316 −0.146 0.257 0.313
** ** ** ** ** **
** Correlation is significant at the 0.01 level (2-tailed). * Correlation is significant at the 0.05 level (2-tailed). If r = 1, the correlation is said to be perfect positive. If r = −1, the correlation is
said to be perfect negative. If r = 0, the variables X and Y are said to be uncorrelated. If 0 < r ≥ 0.4, low correlation. If 0.4 ≤ r < 0.7, moderate correlation. If 0.7 ≤ r < 1, high correlation. [52].
Sustainability 2022, 14, 12051 13 of 16
5. Conclusions
The attempt to map the research landscape of mangrove ecosystem services by synthe-
sizing the contemporary scientific literature yielded a better perspective and understanding
on the context. Considering the complex dimensionality of socio-ecological interactions
between the mangrove ecosystem services, categorizing them into 26 ecosystem services
gave a broader overview regarding nature’s contributions for human well-being. The
evaluation helped to understand the inter-connectedness of ecosystem services in terms of
synergies and trade-offs. Present synthesis clearly reflects the dominant bias of existing
research studies towards regulating ecosystem services. Whereas, in contrast, cultural
ecosystem services have been somewhat overlooked as high economic benefits were not
directly linked to it. The quasi-quantitative approach adopted for the evaluation of research
studies clearly demonstrated that a strong relationship exists between mangrove ecosystem
services and their role in localizing SDGs, particularly for SDG 12 (responsible consumption
and production), SDG 13 (climate action), and SDG 15 (life on land). However, though not
documented in research papers it is clear that in achieving SDG 12, 13 and 15 mangroves
ecosystem services will help in achieving in other SDGs viz. SDG 1 (no poverty), SDG 5
Sustainability 2022, 14, 12051 14 of 16
(gender equality), SDG 8 (decent work and economic growth), SDG 10 (reduced inequality),
etc. Lastly, the Spearman correlation coefficient (r) calculated to have an in-depth under-
standing of the degree of relationship between the sub-categories of mangrove ecosystem
services, and demonstrated that a strong synergistic relationship (r = 0.963) exists between
coastal protection and carbon sequestration. In contrast, the strongest negative correlation
(r = −0.400) exists between freshwater provision (P6) and water transport (P8). Since this
research does not consider the spatio-temporal variations while evaluating the correlation
between categories of ecosystem services, more research is needed to understand such
spatial association between types of ecosystem services. Nonetheless, the synthesis of
knowledge provided in this paper can be of immense benefit for policymakers to advocate
decisions at the local level and mainstream mangrove benefits and their participatory con-
servation for localizing SDGs. This study can further act as the basis for decision-making
to promote sustainable forest management, mangrove restoration, and rehabilitation for
the well-being of marginalised coastal communities in light of sea level rise and increasing
extreme climate events in coastal areas.
Supplementary Materials: The following supporting information can be downloaded at: https:
//www.mdpi.com/article/10.3390/su141912051/s1, Table S1: Number of research studies that have
linkages with Sustainable Development Goals; Table S2: Number of research studies that mention
about each sub-category of mangrove ESs; Table S3: List of research studies based on categorization
of ESs.
Author Contributions: Conceptualization, R.D.; methodology, R.D. and K.B.; Data collection and
analysis: K.B.; writing—K.B. and R.D.; review and editing, S.H., I.S. and S.D. All authors have read
and agreed to the published version of the manuscript.
Funding: This research work is supported by the Asia-Pacific Network for Global Change Research
(APN) under the Collaborative Regional Research Programme (CRRP) with grant number CRRP2018-
03MY-Hashimo.
Institutional Review Board Statement: Not applicable.
Informed Consent Statement: Not applicable.
Data Availability Statement: All data is available in the Supplementary Material.
Conflicts of Interest: The authors declare no conflict of interest.
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