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Home > Studies on the Factors Affecting the Macrobenthic Community Structure of the Exposed Sandy Beaches Near Karachi, Pakistan

Studies on the Factors Affecting the Macrobenthic Community Structure of the Exposed Sandy Beaches Near Karachi, Pakistan

Thesis Info

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Author

Nazia Arshad

Program

PhD

Institute

University of Karachi

City

Karachi

Province

Sindh

Country

Pakistan

Thesis Completing Year

2018

Thesis Completion Status

Completed

Subject

Zoology

Language

English

Link

http://prr.hec.gov.pk/jspui/bitstream/123456789/10047/1/Nazia%20Arshad_Zoology_2018_Uok_PRR.pdf

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676727340471

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The principal objective of the research conducted during this study is to provide a profound knowledge of the ecological status and functioning of exposed sandy beaches of Karachi coast. This assessment was established on the basis of functionally important benthic community structure in response to environmental conditions which is the first comprehensive study at studied beaches at Karachi coast. In chapter 1, macrobenthic community structure of the exposed sandy beaches of Sandspit and Hawksbay in relation to physicochemical parameters and sediment characteristics is studied during 2013-2014. A total of 96 samples were collected in duplicate by quadrat (0.25 m-2) method from high tide (HT) and low tide (LT) mark for macrofauna abundance and sediment analysis from four stations (S1, S2, H1 and H2). Water samples were analyzed for temperature, salinity, pH, dissolved oxygen and nutrients analysis (NH4, NO3, PO4) by applying standard methods. Sediment samples were divided into three layers, each layer was analyzed for moisture and organic content and grain size analysis. A total of 1307 organisms 0.25m-2 belong to 83 macrobenthic species recorded during this study out of which 12 species are first records from Pakistan. A sum of 662 organisms 0.25m-2 were recorded from Sandspit and 645 organisms 0.25m-2 from Hawksbay. The most diversified macrobenthic groups of species were polychaeta (38%) followed by gastropoda (24%), crustacea (19%) and bivalvia (12%) respectively. Whereas, the most abundant faunal groups were polychaeta (44 %), crustacea (25 %), bivalvia (14 %) and gastropoda (11%). Euterpina acutifrons, Glycera alba, Donax hanlyanus, Prionospio sp. were the most dominant species at studied beaches. SIMPER analysis showed average similarity 37.5% between sites. The highest macrobenthic abundance was recorded in NEMS (414 0.25m-2) and PRMS (379 0.25m-2) and lowest during SWMS (211 macrobenthos 0.25m-2). ANOVA showed impact of different environmental parameters such as salinity, temperature, dissolved oxygen and moisture content on macrofaunal assemblages. The species composition and abundance showed a clear separation between studied sites during monsoon seasons indicating the significant impact of monsoon on macrofaunal diversity and abundance at studied beaches. xviii In chapter II, benthic foraminifera in relation to habitat conditions and seasonal influences was studied for the first time from Pakistani coast, based on 48 core samples collected monthly with the help of hand corer (diameter =3 cm) from stations as discussed for Chapter I. For this study the top 0-2 cm sediment slice was analyzed for both living and dead foraminiferal assemblages. A total of 6615 cm-2 specimens consisting of 3451 cm-2 dead tests and 3164 cm-2 living specimens were recorded which belong to 66 species out of which 47% species are miliolina, 42% rotaliina, 9% textulariina and 2% are spirillina. At Sandspit 3197 cm-2 specimens were recoded while a sum of 3418 cm-2 specimen were recorded from Hawksbay. The highest abundance was exhibited by rotaliina, milolina and textulariina respectively. The most dominant rotaliina species were Ammonia beccari, Pararotalia stellata, P. vensuta, Elphidium crispum and E. advenum respectively and Quinqueloculina bicarinata, Q. vulgaris, Miliolinella subrotunda, Spiroloculina antillarum and Miliamina sp. were abundant miliolina species. SIMPER showed that average dissimilarity between foraminifera abundance at Sandspit and Hawksbay is 18.51 %. The stations within sites showed similarity (82.83 % at Sandspit and 84.65 % at Hawksbay). A. beccari and P. stellata are the most similar species within stations at both Sandspit and Hawksbay. The highest foraminifera abundance was recorded in NEMS (3232 cm-2) and SWMS (1984 cm-2) and the lowest during PRMS (398 cm-2). pH, salinity, organic content and nutrients appeared to effect the foraminiferal assemblages. Benthic community structure of exposed sandy beaches of Sandspit and Hawksbay do not affected by a single physicochemical and environmental factor but multiple factors are controlling spatial and temporal distribution of macrofaunal and foaraminferal assemblages at these beaches. The most significant and governing factor for benthic abundance and diversity at these beaches is the monsoon season. Faunal assemblages on each site point out a variability in domination of species during studied seasons. Northeast monsoon was the most biologically productive season which provided a suitable environment for growth of both macrobenthic communities and foraminiferal assemblages. This is the first comprehensive study about ecological status of these highly dynamic environments which will be helpful in management of these beaches in future.
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36. Ya. Sin./Yaseen

36. Ya. Sin./Yaseen

I/We begin by the Blessed Name of Allah

The Immensely Merciful to all, The Infinitely Compassionate to everyone.

36:01
a. Ya. Sin.

36:02
a. The Qur’an - full of Wisdom is an evidence of the fact that -

36:03
a. truly, you - O The Prophet - are of The Messengers,

36:04
a. - guided upon the Right Path,

36:05
a. it is a revelation being sent down onto you by The Almighty, The Infinitely Compassionate,

36:06
a. so that you can warn a people whose forefathers were never warned,
b. so they have remained heedless of the true faith and right guidance.

36:07
a. Indeed, the Word of misguidance is bound to be true against most of them, so they are not going to believe.

36:08
a. Indeed, WE have placed iron collars around their necks, up to their chins, so their heads are upturned, aloft and made stiff-necked so as not to see the Right Path.

36:09
a. And WE have set a barrier in front of them and a barrier behind them,
b. thus WE have blindfolded them from all sides in the darkness of ignorance so they can no longer see the light of truth and guidance.

36:10
a. Thus, it is all the same to them whether you warn them, or do not warn them,
b. they are not going to believe.

36:11
a. However, you can only warn someone who
- follows the Reminder – The Qur’an - and
- remains in awe of The Immensely Merciful despite not...

قدیم سودی مالیاتی نظام کا تحقیقی جائزہ

Ontemporary modern interest-bearing financial system, “economicsystem”, has become an integral part and the prevalent system reflects that in the modern progressive era of growth where other arts have seen progress than in the old days the modern interest bearing system has become a part of the financial development. Interest in the present era has being understood as a direction for financial growth and development of economy hence in some way or the other been tried to be enforced in to the Islamic world such that it becomes a need and no country can live without. And the objectives of this interest bearing system can meet their targets. In Muslim countries minds that do not have deep commitment with Islamic teaching have been convinced in a way that in the ancient days this level of interest was not needed as in the present era. So, on the interest of present day “riba” can’t be applied whose prohibition is proved by Islamic law. The impression that interest is the need of modern times in ancient times to modern times thislevel of interest is not required, nor was there any specifically organized circle like today concept the financial system may be of interest not only if favor of contemporary practice in the present, but also an extremely ancient system was out there and have some evidence of old banking practices. This article, with the vividness of ancient religions, has proved that “interest” in antiquity is as same as of today. The form of interest and its impacts aren’t get changed by the change in ancient or current business practices. Interest is interest, whether it is found in ancient religions or at theadvent of Islam or even after that in the modern day. It embodies the same “riba” whose prohibition is proved in the Islamic sharia.

An Evolutionary Approach to Unsupervised Color Image Segmentation

The process to divide or partition a color image into a set of non- overlapping regions (segments) is called color image segmentation. Color image segmentation can be performed through clustering process by con- sidering the features of each pixel as a pattern and a set of pixels, having similar features or characteristics as a cluster ( segment). Generally, the effectiveness of a clustering algorithm depends on the number of clusters (should be known in advance), initialization of the search space and the searching behaviour of the algorithm. In this work, clustering based algorithms are proposed for color image segmentation which not only determine the number of clusters automat- ically, but also generate compact and well separated segments. First, a hybrid genetic algorithm, called Spatial Fuzzy Genetic Algorithm (SFGA) is proposed which incorporate the colour and spatial information to optimize the fuzzy separation and global compactness simultaneously. The Self Organizing Map (SOM) is adopted to find out the number of clusters (segments) automatically. To initialize the SOM network and SFGA to the productive regions, the dominant peaks in the color his- togram of the wavelet transform image are determined. The problem of over-segmentation is handled with a simple pruning technique. The second contribution is the incorporation of objective function i.e. the ratio of multiple cluster’s overlap to the fuzzy separation into genetic algorithm called Dynamic Genetic Algorithm (DGA). DGA is capable to adjust the number of clusters automatically. Finally, the segmenta- tion of color images are performed by Modified Adaptive Differential Evolution Algorithm (MoADE). MoADE has the ability to automat- ically adjust the crossover and mutation parameters according to the underlying distribution. Moreover to reduce the computational cost the MoADE is applied to the superpixel segmented image. An opposition based strategy is adopted to initialize the population to the productive areas in the search space. The effectiveness of the proposed approaches are tested on Berkeley Im- age Segmentation Database and Benchmark (BSD) with comprehen- sive quantitative and qualitative evaluations. The experimental results demonstrate that the proposed image segmentation methods perform better when applied to complex color images.