Ecological Roles of Benthic Community in Seafloor Northwards of Pulau Indah, Klang, Malaysia

Trait assessment is an alternative but effective method of biomonitoring benthic community in ecosystem, but it was rarely done in Malaysia. An assessment was done to identify the dominant sub-traits, or modalities, within benthic community in seafloor northwards of Pulau Indah, Klang, Malaysia, and to establish possible correlation between modalities with environmental parameters measured in the area. Sampling was conducted in November 2018, during Northwest Monsoon season. Sediments were obtained by using a Ponar Grab and filtered through 500 μm sieve. Sediments were subjected into Loss of Ignition method to extract organic carbon, and filtration method to determine particle size distribution percentages. 37 taxa were recorded in this study, totalling to 848 individuals. Traits assessment indicated vermiform body shape, direct larval development, deposit feeder, non-motile, asexual reproduction, and second-order opportunistic group as most dominant modalities in the study area. Station 1 recorded highest macrobenthos density (21000 ind./m2), while station 5 recorded highest diversity (H’=2.19). Functional diversity (FD) for reproduction method was highest in station 1 (FD=0.61), ecological group in station 4 (FD=0.73); body shape (FD=0.56) and larval development (FD=0.63) in station 5, and lastly, adult mobility (FD=0.70) and feeding mode (FD=0.66) in station 6. Principal component analysis showed Station 1 has most modalities attributed towards it. Pearson correlation analysis suggested particle size distribution as major connector for most modalities (P=0.05). As BTA study is still new in Malaysian waters, it could serve as a good starting point for future assessment related to ecological functioning of benthic community in Malaysian seafloor.

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Evolution of rattling particles in deviatoric shear deformation of granular material

EPJ Web of Conferences ◽

10.1051/epjconf/202124911017 ◽

2021 ◽

Vol 249 ◽

pp. 11017

Author(s):

Lisha Luo ◽

Zhifu Shen ◽

Xudong Wang ◽

Hongmei Gao

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Granular Material ◽

Size Distribution ◽

Critical State ◽

State Parameter ◽

Deformation Pattern ◽

Starting Point ◽

Sample Density ◽

Internal Deformation

Granular material such as clean sand in geotechnical engineering is characterized by structured internal deformation pattern and some interesting particle arrangement patterns. This study focuses on the evolution of the fraction of rattling particles in deviator deformation until the critical state. Numerical simulations using the discrete element method reveal the presence of rattling particles (with zero or only one contact with neighbouring particles) even in a very dense packing system. The results show that the initial fraction of rattling particles depends on sample density and particle size distribution. With the increase of deviator strain, the number and volume fractions of rattling particles gradually approach a steady critical state from either a loose or a dense starting point. An effective void ratio, which is calculated by treating rattling particles as voids, can be viewed as new state parameter describing the effective packing density of sands. Besides, the rattling behaviour strongly depends on particle size distribution.

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Distribution of Benthic Macroinvertebrates in Seafloor Northward of Pulau Indah, Klang

Pertanika Journal of Science and Technology ◽

10.47836/pjst.29.1.34 ◽

2021 ◽

Vol 29 (1) ◽

Author(s):

Mohd Sophian Mohd Kasihmuddin ◽

Zaidi Che Cob

Keyword(s):

Particle Size ◽

Benthic Macroinvertebrates ◽

Benthic Community ◽

Diversity Index ◽

Pearson Correlation ◽

Environmental Parameters ◽

Physical Parameters ◽

Sediment Particle ◽

Sediment Particle Size ◽

Starting Point

An assessment of community of benthic macroinvertebrates in waters northwards of Pulau Indah, Klang was made with the main objective to determine distribution and diversity of benthic macroinvertebrates as well as to establish possible correlation between the community’s distributions with environmental parameters. The sediments were obtained via Ponar Grab (0.023 m2 mouth area), followed by filtration (500 μm) and laboratory sorting in order to extract all specimens from sediments. The specimens were identified to the lowest taxonomic hierachy as possible. The physical parameters such as organic carbon (TOC) and grain size distributions were analysed. A total of 775 annelids, 15 arthropods, 12 echinoderms and 32 molluscs individuals were identified and recorded in six stations overall. Family Cirratulidae accounted to the highest numbers of the Annelids (n=358), whilst Cerithidae recorded as highest numbers of Molluscs. Station 5, 6 and 1 recorded the highest diversity index (H’=2.1845), evenness index (J’=0.6316) and richness index (Dmn=22.0454) respectively. Principal Component Analysis indicated sediment particle size as the major connector on all stations, with different station correlated to certain sizes of sediment particle. Pearson correlation analysis showed positive correlations between environmental parameters with eight benthic taxa in this study, with most correlations were on specific sediment particle size. As the study of benthic community is still inadequate in most of Malaysians waters, particularly in highly industrialised area such as waters in Port Klang, this study can serve as a starting point for any future studies concerning ecological disturbance affecting benthic community in Malaysian waters.

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Prediction of Breakage During Roller Milling of Wheat Kernels, Based on Single Kernel Measurements

Jurnal Teknologi ◽

10.11113/jt.v48.235 ◽

2012 ◽

Author(s):

Ida Idayu Muhamad ◽

Chaoying Fang ◽

Grant M. Campbell

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Independent Data ◽

Flour Milling ◽

Starting Point ◽

Breakage Function ◽

Efficient Recovery ◽

Roller Milling ◽

Wheat Kernels

Pengilangan tepung gandum melibatkan pengisaran bijirin secara berulang-kali (menggunakan roller mill) dan pemisahan (secara pengayakan) bagi perolehan semula hasilan tepung yang berkesan yang secara bandingannya bersih dari pencemaran bran. Satu permulaan bagi membina model perlakuan terhadap campuran bijirin gandum ialah keupayaan bagi menentu-ukur kelainan ciri-ciri yang wujud dalam campuran tersebut. Alatan Perten Single Kernel Characterisation System (SKCS) dapat memberikan taburan kuantitatif bagi jisim, kandungan lembapan, garis pusat dan nilai kekerasan bagi campuran bijirin tersebut, berdasarkan pengukuran 300 kernel dalam masa 5 minit. Cabarannya ialah menghubungkaitkan taburan yang telah ditentukur kepada ramalan keupayaan pengilangan. Pada tahap ini, satu bentuk kefungsian pengisaran (breakage function) dalam konteks parameter tentu-ukuran bagi setiap kernel bijirin telah diterbitkan, dan diintegrasi kepada taburan sifat kernel menggunakan persamaan proses pengisaran (breakage equation). Dengan menggunakan model tersebut, satu jangkaan boleh dilakukan ke atas taburan saiz partikel hasil keluaran pengisaran siri pertama atau First Break roller milling bagi kernel bijirin yang berbeza saiz, kekerasan dan kelainannya, berdasarkan hanya pada ciri-ciri taburan yang diberikan oleh SKCS. Model tersebut telah diuji ke atas hasil keluaran pengisaran pada disposisi (roll disposition) pengisaran sharp-to-sharp dan dull-to-dull, dan didapati menunjukkan keseragaman dengan data bebas (independent data). Kata kunci: Tingkah laku pengisaran, taburan saiz partikel, pemecahan, pengujian satu–kernel, bijirin Wheat flour milling involves repeated breakage (by roller milling) and separation (by sifting) of flour particles to give efficient recovery of fine flour relatively free from bran contamination. A starting point for modelling the behaviour of mixtures of wheat kernels is to be able to measure the variation in kernel properties within the mixture. The Perten Single Kernel Characterisation System (SKCS) gives the distributions of kernel mass, moisture content, diameter and hardness within a mixture, from 300 kernels within 5 minutes. A challenge remains to relate these measured distributions to predictions of milling performance. To this end, a breakage function in terms of these measured parameters for individual kernels has been constructed, and integrated over the distribution of kernel properties using the breakage equation. These models allow prediction of the output particle size distribution delivered by First Break roller milling of kernels varying in size, hardness and variety, based entirely on SKCS characteristics. Predictions have been developed for both sharp-to-sharp and dull-to-dull roll dispositions, and show encouraging agreement with independent data. Key words: Milling behaviour, particle size distribution, breakage, single kernel testing, wheat

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