Department of Life Sciences, Maharaja Krishnakumarsinhji Bhavnagar University Bhavnagar | 2018
Ph.D. Thesis | Faculty: Science | Subject: Zoology | Imtiyaz Beleem
PREFACE AND OUTLINE OF THE THESIS
Ecology of marine crabs possess the life-cycle, competition, predation, feeding,
migration and species-environment relationships. Population ecology dealt with the
population dynamics of the species which interact with their surrounding
environment. The main concept of population ecology is to predict species
distribution within the study area. The dynamics of population shows population size,
density and abundance where population size change over time. The resources
limitation factor affected the population size where environment sustain maximum
population size called carrying capacity.
Present study dealt with taxonomy, diversity and population ecology of few selected
marine crab. Entire study was divided into two phase, the first phase is taxonomical
identification of marine crabs whereas second phase is population ecology of some
selected crabs of Diu Island, India. Coastal characteristics zone wise were noted for
each selected sites of Diu. Marine crabs identified with the help of recent taxonomic
literatures and taxonomically described with their distribution status worldwide.
Spatial and temporal distribution of few selected marine crab were taken in to account
to know the relationship of species with coast. Population attributes such as density,
abundance and frequency were analyzed through standard formula.
Entire thesis is divided into 06 chapters where chapter 1 describes the marine
environment, coastal characteristics, marine crab taxonomy, distribution of species,
concept of population ecology and DNA sequence analysis information. Aim and
objectives are given at the end of Chapter 1.
Chapter 2 describes review of literature on taxonomy of marine crab from past to
present where they classified according to different authors, updating of classification
and recent classification methods. Chapter describe the review of literature into two
section of anomuran and brachyuran crabs. Species describe, redescribed as a result
erected new family or genera or species briefed. This chapter also describe review
work done on population ecology and molecular phylogeny work done by various
authors from worldwide to Gujarat state to know the present status of marine crabs.
Chapter 3 describes materials and methodology of present research work. This
chapter divided into few subsection such as study area, sampling sites and coastal
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Department of Life Sciences, Maharaja Krishnakumarsinhji Bhavnagar University Bhavnagar | 2018
Ph.D. Thesis | Faculty: Science | Subject: Zoology | Imtiyaz Beleem
characteristics. Sampling methods for crab collection, taxonomy, molecular
phylogeny, sampling methods for population ecology with biodiversity indices and
data analysis are described in brief. This chapter useful to cover all the aspects of
research like taxonomy, population ecology and molecular phylogeny of marine
crabs. Marine crab were taxonomically identified to prepare checklist and to assess
population of selected marine crabs analyzed with the help of modern tools and
techniques. Biodiversity indices were used to study distribution pattern of marine crab
on the vertical zones of Diu coast.
Chapter 4 describes the result of the present study. In this section taxonomy of
marine crabs were described with their synonymy, diagnosis, habitat and distribution
in the world. Diversity, distribution and present checklist of marine crabs of Diu
coastline were prepared with their zone wise habitat preference. A checklist of marine
crabs also prepared to compare the status of crabs in Diu coast. This chapter is divided
into few sub-sections such as taxonomy, marine crab diversity, community structure
of marine crabs and population ecology.
Chapter 5 describes discussion of present result with similar studies occurred from
various regions of the world. Species taxonomy and diversity was also discussed and
compared with the other recorded species to evaluate the spices diversity of Diu coast.
Population status and DNA sequencing of present study was also compared with the
previous similar studies of different regions.
Chapter 6 describes conclusion of entire study where author explained the outcome
of the study. After that author described the summary of the present study that stated
the abstract of the entire study. Present study finished up with recommendation and
authors views regarding this research work carried out and to be done on diversity and
population status of marine crab of Diu coast, India. Literature cited in the main text
is listed in reference section.
2
Department of Life Sciences, Maharaja Krishnakumarsinhji Bhavnagar University Bhavnagar | 2018
Ph.D. Thesis | Faculty: Science | Subject: Zoology | Imtiyaz Beleem
General idea about the research problem
The western coast of India is divided into five maritime states such as Gujarat,
Maharashtra, Goa, Karnataka and Kerala. West coast possess 3,297 km long coastline
in which Gujarat has the longest coastline about 1600km. Gujarat coast stretched from
Sir Creek in the north-west to Umargao in the south-east, which having one-third of
the Indian coastline. The coast occupied having two gulfs (Gulf of Kutch and Gulf of
Khambhat) and a peninsula (Saurashtra peninsula).
Diu Island is one of the Union territory of India, which is located near Una tehsil of
Saurashtra coast, Gujarat. Eastern part of Diu possesses ridges of miliolite, central
part composed of calcareous sand dunes and the western part with flat terrain. Tidal
zones are composed of clay beds. On the coast main source of rock is miliolite,
calcarenite, calcrudite and micrite. Mostly calcareous clay, shell-sand, sand dunes
comprise mainly, shell fragments of coral, foraminifera and mollusks (Prakash et al.,
2012).
Gujarat coastline have been extensively surveyed for marine crab diversity, taxonomy
and distribution. Comprehensive work on taxonomy of marine crab were carried out
in Gujarat coast (western coast) by various authors such as Hornell and Southwell
(1909); Chhapgar (1957a, b; 1961; 1958b); Chandy (1970) whereas Dev Roy, (2013)
compiled a checklist of 66 species brachyuran crabs from Gujarat state. Recently,
Trivedi and Vachhrajani (2016) compiled a checklist of 112 species belonging to 26
genera in 05 families from Indian coast. Taxonomy and checklist compilation were
done frequently by various authors in Gujarat coast but aspect such as population
ecology and anthropogenic pressure on marine crab of particular area remain scanty.
Present research work was carried out to assess the taxonomical identity, diversity,
distribution, habitat preference and spatio-temporal distribution of marine crabs.
Systematics and present taxonomy of each marine crabs were investigated through
modern taxonomic method. A comprehensive checklist with habitat preference of
marine crabs of Diu coast was prepared and compared with previous studies of
Gujarat coast. Distribution of each species was noted with habitat type to assess the
relation of species specific habitat. There were no previous studies on population
status of particular crab species of Gujarat, hence present study reported the
population status with spatio-temporal variation selected sites of Diu. In addition,
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Department of Life Sciences, Maharaja Krishnakumarsinhji Bhavnagar University Bhavnagar | 2018
Ph.D. Thesis | Faculty: Science | Subject: Zoology | Imtiyaz Beleem
DNA sequencing analysis was undertaken for a single family of porcelain crabs of
Gujarat waters to understand phylogenetic relationship among the species.
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Preface and Outline of the Thesis
2011
Ecology of marine crabs possess the life-cycle, competition, predation, feeding, migration and species-environment relationships. Population ecology dealt with the population dynamics of the species which interact with their surrounding environment. The main concept of population ecology is to predict species distribution within the study area. The dynamics of population shows population size, density and abundance where population size change over time. The resources limitation factor affected the population size where environment sustain maximum population size called carrying capacity....Read more
