The purpose of this study was to produce a novel pH sensitive hydrogel with superior thermal stability, composed of
poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali
and bleaching treatments followed by acid hydrolysis. PAA was then subjected to chemical cross-linking using the crosslinking
agent (N,N-methylenebisacrylamide) in CNC suspension. The mixture was casted onto petri dish to obtain disc
shape hydrogel. PAA/cellulose hydrogel with the same composition ratio were also prepared as control. The effect of
reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH
was studied. The obtained hydrogel was further subjected to different tests such as thermogravimetric analysis (TGA) to
study the thermal behavior, Fourier transform infrared for functional group identification and swelling test for swelling
behavior at different pH. The cross-linking of PAA was verified with FTIR with the absence of C=C double bond. In TGA
test, PAA/CNC hydrogel showed significantly higher thermal stability compared with pure PAA hydrogel. The hydrogel
obtained showed excellent pH sensitivity and experienced maximum swelling at pH7. The PAA/CNC hydrogel can be
developed further as drug carrier
In order to examine differences of meat quality traits depending on pH values post-mortem, the pH range was classified
according to initial pH (pH45min) and ultimate pH (pH24hr) post-mortem. The differences of meat quality traits depending
on sex were not changed by a number of amount, except for backfat thickness and fat content. The value of pH45min was
positively correlated with pHdif, whereas pH24hr was negatively associated with lightness (CIE L*) and protein content. At
pH45min post-slaughter, collagen content, fat content, shear force, water holding capacity and yellowness (CIE b*) showed
lower values at the higher pH range of pH>6.7 than those of other ranges, but CIE L* and redness (CIE a*) presented
the lowest value at the intermediate pH range of pH6.3~6.7. Conversely, at pH24hr post-slaughter, fat and moisture
contents maintained the highest average values at the higher pH range of pH>6.1, but protein content showed higher
value at the lower pH range of pH<5.7. Higher pH24hr appeared significantly lower shear force, but higher water holding
capacity. CIE L*, a*, and b* values showed significantly higher values at the lowest region of pH24hr. Since meat quality
characteristics seemed to be favored by consumers in rather than at the range of pH5.7~6.1, which showed significant
differences of meat color, appearance, and meat juiciness, it is suggested that production of pork meat to appropriate
pH value is performed by pig breeders and control measures taken during pre- and post-slaughters.
The Alur Lebey fault zone, which is paralled to part of Sungai Lebey, is exposed along the East-West Highway at km 221.5 to Kota Bharu. The outcrop is about 155 m wide on the east and 105 m wide on the west side of the road. Fault morphology can be recognised from the faceted hill spurs along the valley. The fault zone has been interpreted as a lithological contact between metavolcanic in the west and metaclastic in the east. The northern extension of the fault was interpreted as the contact between silicous pelite in the west, and chert and siliceous pelite in the east. Even though left lateral motion is exhibited within the zone, evidences of right lateral motion were also observed. On Landsat 3 image, a lineament in the direction of 355° representing the Alur Lebey fault zone could be traced for some 55 km from the East-West Highway to the middle of east Pattani River in Thailand. The outcrop at the East-West Highway comprises medium indurated mylonite containing lenses of quartz and tuff. Other than asymmetric lenses, quartz also occurs in the form of a comma, and pinch-and-swell structures. These forms of clasts are used to determine the sense of movements along the fault. In general, steeply to vertically dipping mylonite strikes towards the north. Fault planes with horizontal senses of motion cut the foliotion at an acute angle. Some of these fault planes are parallel to the foliation. There are also reverse fault planes with medium to gentle dips to the west. General motions of the fault were tOwards the east southeast. The mylonite foliation which strikes north contains evidences of both left and right lateral motions, whereas the northwest striking foliation exhibits left lateral motion. Several fault-associated folds plunging towards the north northwest, south southwest and east were observed in the fault zone. The combination of field observations and structural analysis are used to arrive at the interpretation on the history of the fault zone. Four systems of compressions (maximum principal stresses) can be deduced from the study. these are the north-northeast, east-southeast, east-southeast, and the youngest north-northeast directions. The oldest deformation is characterised by dextral movement along the mylonite zone. the zone contains asymmetric lenses of tuff and quartz striking 355° to 05°. The sinistral movement along mylonite fooliation striking 354° and 326° is the evidence of the east-southest compressive stress system. Both deformation episodes could represent aseismic faultings under fairly high confining pressure. However the recurrance of the east-southest stress system could have caused the sinistral movement along the northwest and north striking fault planes, the reverse faulting on south to southwest planes and the resulting drag folds. The dextral movement along the north and northwest planes is the youngest deformation episode. The final two episodes could represent brittle deformation resulting from the shallow position of the rock body at least along that particular fault segment.
Zon sesar Alur Lebey yang selari dengan sebahagian Sungai Lebey, tersingkap di km 221.5 dari Kota Bharu di lebuhraya Timur-Barat. Panjang singkapan keratan di timur jalan di sekitar 155m, manakala di barat jalan pula 105m. Morfologi sesar ditunjukkan oleh barisan susuh bukit beifaset di sepanjang lembah. Di lapangan dan di peta geologi, sesar ini ditafsirkan sebagai sempadan di antara metavolkano di baratnya dan metaklas di timurnya. Lanjutannya ke utara ditafsirkan bahawa sesar tersebut memotong sepanjang sempadan di antara pelit bersilika di barat dan rijang serta pelit bersilika di timur. Sungguhpun gerakan mendatar ke kiri terpamer dalam milonit, namun pergerakan mendatar ke kanan boleh dicerap dalam zon tersebut. Dalam area Lansat 3 bertarikh 10 Januari 1979 lineamen berjurus 355° yang mewakili zon sesar Alur Lebey dapat dikesan sepanjang 55 Ian dari Lebuhraya Timur-Barat hingga ke pertengahan bahagian timur Sungai Pattani di Thailand. Singkapan sesar tersebut terdiri daripada milonit separuh terluluhawa yang mengandungi kekanta kuarza dan tuf. Selain berbentuk kekanta, kuarza juga berbentuk koma, dan ramping-dan-ampul. Klas yang berbentuk tersebut digunakan untuk menentukan hala pergerakan dalam zon sesar. Umumnya milonit menjurus ke utara dengan kemiringannya euram hingga tegak. Satah-satah sesar mendatar memo tong foliasi milonit pada sudut tirus atauJdan ada pula yang selari dengannya. Selain sesar mendatar terdapat pula sesar songsang yang kemiringannya landai hingga sederhana ke barat. Gerakan umumnya menyongsang ke timur-tenggara. Foliasi milonit yang menjurus ke utara mengandungi tanda-tanda pergerakan ke kiri dan ke kanan, manakala foliasi yang menjurus ke baratlaut mengandungi hanya pergerakan mendatar ke kiri. Sebilangan lipatan yang berkait-rapat dengan sesar menunjam ke utara-baratlaut, selatan-baratdaya dan ke arah timur dieerap di dalam zon sesar tersebut. Gabungan eerapan lapangan dan analisis struktur akhirnya sampai kepada pentafsiran sejarah canggaan yang berlaku di dalam zon sesar tersebut. Empat sistem tegasan boleh disimpulkan. Sistem tegasan maksimum (mampatan) tersebut ialah .utara-timurlaut, timurÂtenggara, dan yang termuda utara-timurlaut. Canggaan tertua dicirikan oleh pergerakan dekstral di sepanjang zon milonit yang mengandungi kekanta tuf dan kuarza yang asimetri berjurus 355° hingga 05°. Pergerakan sinistral di sepanjang milonit yang berjurus 354° dan 326° merupakan bukti daripada sistem tegasan timur-tenggara. kedua-dua episod canggaan mungkin mewakili penyesaran aseismos yang berlaku dalam sekitaran tekanan mengepung yang tinggi. Namun demikian perulangan tindakan sistem tegasan timur-tenggara menyebabkan pergerakan sinistral di sepanjang satah sesar berjurus baratlaut dan utara, penyesaran songsang di atas satah berjurus selatan hingga baratdaya dan lipatan seret. Pergerakan dekstral di sepanjang satah berjurus utara dan baratdaya merupakan episod canggaan yang termuda. Dua episod yang terakhir mungkin mewakili canggan rapuh akibat daripada kedudukan cetek jasad batuan sekurang-kurangnya di sepanjang segmen sesar tersebut.
Sn doped zinc oxide polycrystalline thin films were prepared by sol-gel process. The sol was prepared from zinc acetate dehydrate and tin chloride were used. 2-methoxyethanol and monoethanolamine were used as the solvent and stabilizer, respectively. The quantity of tin in the sol was 0, 15, and 25 at.% Sn with annealing temperature 400, 500 and 600°C. Structural investigation including surface morphology and microstructure was carried out by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The films give a hexagonal wurtzite structure with diffraction peaks at (100), (002) and (101). Changes in particle size with an increase in annealing temperature were observed in the SEM micrograph. The optical properties were determined by photoluminescence (PL) and UV-Visible (UV-VIS-NIR) spectrometer. The band gaps increased (2.78 eV to 4.10 eV) as the concentration of Sn was increased and the increasing of annealing temperature. Annealing temperature plays a key role in the formation of defects which is strongly related to the nonradiative recombination centers. The increment of the band gap is acceptable as a requirement for good anti-reflecting coating element. Therefore, these films can be applied on silicon solar cells.
A ZnO gas sensor was successfully prepared by RF sputtering. The maximum sensitivity of the sensor for vinegar test application was at 400oC. The ZnO based sensor showed good sensitivity for vinegar test in the concentration range of 4% to 9%. The work reveals the ability of using ZnO gas sensor to determine the acid concentrations of the vinegars for food requirements.
In this paper, an improved trigonometrically fitted zero-dissipative explicit two-step hybrid method with fifth algebraic
order is derived. The method is applied to several problems where by the solutions are oscillatory in nature. Numerical
results obtained are compared with existing methods in the scientific literature. The comparison shows that the new
method is more effective and efficient than the existing methods of the same order.
Yield performance in wheat (Triticum aestivum) was compared under crop residue, tillage system and nitrogen rate treatments in cereal based cropping system. The experiments were conducted at Agronomy Research Farm, The University of Agriculture, Peshawar, in 2009-2010 and 2010-2011. Chopped crop residue on dry matter basis (5 t ha1-) of legume (Vigna unguicuata, var. Ebney) and cereal (Zea mays, var. Azam) was applied in main plots with no residue treatments and plowed with Mould Board (MB) and Cultivator as deep and shallow treatments, respectively. A month after the crop residue and tillage system treatments, field was uniformly plowed with cultivator and wheat was sown with drill in rows 25 cm apart in the month of November on both years. Both P2O55 and K2O (80 and 40 kg ha , respectively) were applied uniformly to all fields before sowing. Nitrogen as subplot treatment (0, 40, 80, 120 and 160 kg ha-1) was applied in two splits, half at 15 and the other half at 45 days after sowing with uniform cultural practices for crop growth and development. Compared to year 1, crop of year 2 showed better phenology with extended life cycle (LC). On two years average across tillage and N treatments, biological yield did not change (p<0.05) under the residue but did report lower at no-residue treatment. Nonetheless, grain yield showed a significant (p<0.05) change with the highest in legume followed by cereal and the lowest in no-residue treatments. A non-significant tiller number and significant variations in grain weight and spike m-2 were observed that influenced the grain and biological yield differently. Deep than shallow tillage resulted in better traits, which returned better biomass and grain yield. Nitrogen application from control to every increment showed a significant (p<0.05) improvement in all observations contributing in yield. The study confirms the significance of legume vs. cereal over no-crop residue incorporated through deep tillage system with optimum N (120 kg ha-1) in cereal-based cropping system for sustainable performance to sustain soil C:N for future production.
In recent decades, minimizing the frequency of nutrient deficiency and malnutrition in rural areas of developing
countries becomes an alarming issue. Oyster mushrooms are rich source of both macro and micro nutrients. The
objective of this paper was to evaluate the yield of newly introduced oyster mushroom strains viz. Pleurotus sajorcaju
(PSC), Pleurotus flabellatus (FLB), Pleurotus florida (FLO), Pleurotus ostreatus (PO2
and PO3
), Pleurotus ostreatus
(HK-51) and Pleurotus geesteranus (PG1
and PG3
) and to justify their nutritional values when grown in the climatic
condition of Bangladesh. Strain HK-51 produced the highest amount of fresh sporophore (197.80 g). In contrast, the
highest number of fruiting body was obtained from the strain FLO (82 g) followed by strain PSC (69 g). Strain PG1 has
recorded the highest biological yield (278 g), productivity (55%) and biological efficiency (96%). Nutrient and mineral
analysis of sporophore of strain PG1 showed protein (31.80%), lipid (3.6%), potassium (1.3 mg/100 g), phosphorus
(0.8 mg/100 g), calcium (32 mg/100 g), iron (43 mg/100 g), magnesium (12 mg/100 g), copper (3.5 mcg/100 g), zinc
(12.5 mcg/100 g) and manganese (2.3 mcg/100 g). This study showed that the strain PG1
performed well with regard to
quality and productivity as compared to other strains. Hence, oyster mushroom strain PG1
is a potential cheap source
of nutrients and minerals to combat socioeconomic problems including malnutrition, diseases linked to malnutrition,
poverty reduction and agricultural diversity.
Breeding for hybrid DxP oil palm in many commercial seed producers has recently switched from simple two-way
crosses to complicated multi-way crosses with the hope of increasing hybrid vigour and thus higher yield potential. The
objective of this study was to evaluate the yield potential of the multi-way (MW) crosses as compared to conventional
two way (TW) crosses in United Plantations Berhad. A trial was set up in 2004 where 20 crosses of both multi-way and
two-way combinations were field planted and evaluated for six years after maturity. Palms were assessed for yield traits
and bunch components through bunch analysis. Fresh fruit bunch weight for both types of crosses was significantly
different with MW crosses yielding 37.11 tonnes per ha per year as opposed to TW crosses with 36.40. MW crosses had
1.46 tonnes oil per ha per year advantage over TW. High coefficient of variation (CV%) was seen for selected traits such
as bunch number (BNO), average bunch weight (ABW), kernel, shell and mesocarp to bunch (KB, SB and MB), oil to dry
and oil to wet mesocarp (ODM and OWM), as well as mean fruit weight (MFW). ANOVA showed that replicate (REP), year
(Y) and progeny (ID) were significantly different (p≤0.01) for BNO and fresh fruit bunch (FFB) in both crosses but not
significant for REP in ABW of TW. REP was not significant for all the traits except ODM whereas ID was significant for all
the traits in both TW and MW. Phenotypic and genotypic coefficients of variance (PCV and GCV) were low (<10%) for
all the traits in both types of crosses with MW crosses showing higher PCV and GCV in most cases. Heritability for ABW,
FFB, KB, oil to bunch (OB), SB and MFW were higher in MW crosses but lower for BNO, fruit to bunch (FB), MB, ODM and
OWM compared to TW crosses.
Extraction and chromatographic isolation of the hexane, chloroform and methanol extracts of stem bark of Calophyllum gracilipes has led to the isolation of a new xanthone, gracixanthone (1) and the known zeyloxanthanone (2) and trapezifolixanthone (3) together with three common sterols, namely stigmasterol, friedelin and lupeol. The structures of the compounds were elucidated and established by spectroscopic analysis and compared with the spectral data from literature. The cytotoxicity of the compounds was evaluated and zeyloxanthanone (2) exhibited strong activity towards five cell lines with IC50 values ranging at 8.00-26.00 μΜ.
Xanthine oxidase (XO) is an enzyme that catalyzes the metabolism of hypoxanthine and xanthine into uric acid. XO also serves as an important biological source of free radicals that contribute to oxidative damage involved in many pathological processes. Antioxidant effects of several Primulaceae species have been reported but their XO inhibitory activity has not been investigated. Thus, this study was conducted to determine the XO inhibitory and free radical scavenging activities of Primulaceae species and to correlate these activities with their total phenolic contents (TPC). A total of 129 extracts of different plant parts of twelve Primulaceae species were assayed for XO inhibition spectrophotometrically at 290 nm using allopurinol as a positive control. The antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and TPC of the extracts were determined by the Folin-Ciocalteau method. The Pearson correlation analysis indicated that the TPC of the extracts showed moderate positive correlations with XO inhibition (r=0.31, p<0.05) and DPPH antioxidant activity (r=0.31, p<0.05) for all of the dichloromethane extracts. Amongst the extracts tested, the dichloromethane extract of the roots of Labisia pumila var. alata showed the strongest inhibitory effects for XO (IC50 4.8 μg/mL) and DPPH free radical capacity (IC50 1.7 μg/mL). The results suggested that Primulaceae species, particularly the dichloromethane extract of L. pumila var. alata roots, are the potential source of useful leads for the development of XO inhibitors.
In this report, we demonstrate that continuous improvement in XPS instruments and the calibration standards as well
as analysis with standard component-fitting procedures can be used to determine the binding energies of compounds
containing phosphorus and sulfur of different oxidation states with higher confidence. Based on such improved XPS
analyses, the binding energies (BEs) of S2p signals for sulfur of increasing oxidation state are determined to be 166-167.5
eV for S=O in dimethyl sulfoxide, 168.1 eV for S=O2
in polysulfone, 168.4 eV for SO3
in polystyrene sulfonate and 168.8
eV for SO4
in chondroitin sulfate. The BEs of P2p signals show the following values: 132.9 eV for PO3
in triisopropyl
phosphite, 133.3 eV for PO4
in glycerol phosphate, 133.5 eV for PO4
in sodium tripolyphosphate and 134.0 eV for PO4
in sodium hexametaphosphate. These results showed that there are only small increases in the binding energy when
additional oxygen atoms are added to the S-O chemical group. A similar result is obtained when the fourth oxygen or
poly-phosphate environment is added to the phosphorus compound. These BE values are useful to researchers involved
in identifying oxidation states of phosphorus and sulfur atoms commonly observed on modified surfaces and interfaces
found in applications such as biomaterials, super-capacitors and catalysis.
An efficient and a green route to synthesize phthalide-fused indoline, 3-[(5-chloro-1,3,3-trimethylindolin-2-ylidene)methyl]
isobenzofuran-1(3H)-one (3) has been developed by the coupling reaction of 5-chloro-2-methylene-1,3,3-trimethylindoline,
1 and 2-formylbenzoic acid, 2 under solvent-free domestic microwave irradiation. The compound was produced in 85%
yield. Compound 3 was characterized by analytical and spectral methods and its structure was confirmed by chemical
crystallography. Compound 3 was successfully crystallized in triclinic system with space group Pī. The molecular structure
consists of fused 1 and 2 groups connected by the enamine carbon. Binding study of 3 towards different types of metal
cations was done by colorimetric detection and UV-vis titrations. Compound 3 exhibited good selectivity and sensitivity
for Sn2+ compared to other metal cations tested. The stoichiometric binding ratio of 3 toward Sn2+ is found to be 1:1
and the binding constant (Ka) is 1.07×104 M–1 on the basis of Job’s plot and Benesi-Hildebrand analysis.
Investigation of meteorological disasters caused by small-scale topography shows that flashover due to wind age yaw occurred quite often where col topography existed. Considering that the distribution pattern of wind profile at different locations of a col topography is not clear, this paper, with wind tunnel tests, studied the influenced of such topographic features of a col as hill slope and valley mouth width on the wind profile at different locations. The results of wind tunnel tests indicated that over-hill wind has a stronger effect on wind velocity correction coefficient than does valley wind, that compared to flat terrain wind velocity, the maximum speed-up amplitude of wind velocity at valley throat and hill summit reach 33 and 53%, respectively, apparently higher than 10% specified in Codes, that wind velocity at valley throat increases with the increase of hill slope and decreases with the increase of valley mouth width, that wind velocity in the valley basically does not go up when the slope of one hill side is smaller than 0.1 and that wind velocity at the same non-dimensional height of a 3D hill summit increases with the increase of hill height.
Older adults quite often had an inadequate diet leading to micronutrient deficiencies and impaired immune response with subsequent development of degenerative diseases. This study aimed to determine the adequacy of energy and nutrient intake and its distribution among three aging groups i.e. successful aging (SA), usual aging (UA) and mild cognitive impairment (MCI). This is a cross-sectional study involving a large sample size (n = 2322) of older adults recruited through multistage random sampling from four states of Malaysia. An interview was conducted to measure dietary intake, neurocognitive status and functional status by using the Diet History Questionnaire (DHQ), Mini-Mental State Examination (MMSE), Rey Auditory Learning Test (RAVLT), Geriatric Depression Scale (GDS), Instrumental Activity of Daily Living (IADL) and Quality of Life Questionnaire. For comparison of dietary intake, a sub-sample of 173 respondents from each aging groups were matched and selected using a comparative cross-sectional approach. Women in SA group had the highest mean intake of vitamin A, calcium (p <0.05), vitamin C, riboflavin and iron (p<0.001). The same aging group also achieved the highest RNI percentage for the same nutrients. More than 80% of respondents for all aging groups did not met the recommended nutrient intake (RNI) for vitamin E, thiamin, niacin, folate, calcium and zinc. In women, MCI respondents were more likely to have an inadequate intake of vitamin A, C, riboflavin and iron followed by UA and SA. Inadequate vitamin E, niacin, folate and calcium were prevalent among all gender and aging groups. There is a need to further distinguish specific dietary patterns associated with these three aging groups to promote optimal nutrient intake for cognitive health.
The water chemistry of selected rivers in Kota Marudu, Sabah was studied based on the major ion chemistry and its suitability for drinking and irrigation purposes. Ten sampling stations were selected and water samples were collected from each station to assess its chemical properties. The physico-chemical variables including temperature, electrical conductivity (EC), total dissolved solids (TDS), salinity, dissolved oxygen (DO), pH, turbidity, ammoniacal-nitrogen (NH3-N), biological oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solid (TSS) were measured. The cations (K, Mg, Ca, Na) were analyzed by ICP-MS. Most of the variables were within the drinking water quality standards stipulated by the World Health Organization (WHO) and the Ministry of Health (MOH), Malaysia except for turbidity. Sodium adsorption ratio (SAR) and salinity hazard were calculated to identify the suitability of the water as irrigation water. The Wilcox diagram classifies that only 10% of samples are not suitable for the purpose of irrigation. The overall results showed that most of the rivers in Kota Marudu are still in a clean condition and suitable for drinking and irrigation purposes except for Sumbilingan River, which is considered as slightly polluted. The results are supported by the hierarchical cluster analysis as the stations were grouped into two groups; low and high pollution intensities. This preliminary result can update the baseline data of selected water quality parameters in the Kota Marudu and could serve as tool for assisting relevant government bodies in regulating the water resources policies in the future.
Water quality analysis of the seven feeder rivers in Tasik Chini was carried out from October 2004 to December 2005. A total of nine sampling sites were selected in this study, namely: Sungai Datang (St.1), Sungai Cenahan (St. 2), downstream of Sungai Gumum (St. 3), mid of Sungai Gumum (St. 4), Sungai Kura-kura (St. 5), Sungai Melai (St. 6), Sungai Jemberau (St. 7), upstream of Sungai Paya Merupuk (St. 8), and downstream of Sungai Paya Merupuk (St. 9). Eleven water quality parameters were selected and analyzed in-situ and ex-situ during two sampling seasons. Laboratory analyses were carried out according to the HACH and APHA. Results of the study indicated that the pH content ranged from 3.2 to 6.32, dissolved oxygen 0.27 to 6.4 mg/L, conductivity from 14.33 to 85.7 µS/cm and temperature from 24.1 to 32.1˚C. Total dissolved solids ranged from 22.67 to 184 mg/L, total suspended solids from 1.17 to 79.11 mg/L and turbidity from 4.67 to 28.67 NTU. Nutrients such as ammonical nitrogen (0.01 to 0.57 mg/L), nitrate (0.7 to 2.9 mg/L), phosphate (from not detectable to 0.50 mg/L) and sulphate (from not detectable to 2.0 mg/L) were also studied. This showed that most of the feeder rivers have contributed to high nutrients values in Tasik Chini. Statistically, the relationship between water quality parameters were correlated as very weak and moderately correlated (R2= 0.40). Phosphate and sulphate were significantly correlated as positive slope; turbidity and nitrate showed negative slope with discharge during both the seasons (R2=0.651; R2=0.624). Recent activities such as deforestation, mining, agriculture and tourism have taken place in the surrounding areas of the lake. These activities were expected to influence the stability of the water quality of the feeder river of Tasik Chini.
This study assesses the influence of water quality on fish occurrences in Sungai Pahang, Maran District, Pahang, Malaysia. Water quality and fish samplings were conducted at seven sampling sites in the district for 13 consecutive months. We used canonical correspondence analyses (CCA) to determine the influence of water quality on monthly fish species occurrences. The ranges of water quality parameters were quite high considering the measurements were made during rainy and dry seasons throughout the year. A total of 2,075 individual fish was captured which comprised of 22 different families and 65 species. Family Cyprinidae recorded the highest number of fish species of the area (27 species; 41.5%), followed by Bagridae (five species; 7.69%) and Pangasiidae (five species; 7.69%). Three fish species categorized as endangered, including Balantiocheilos melanopterus, Probarbus jullieni and Pangasianodon hypophthalmus were also collected. The collected fish species were divided into three groups (A to C), which was clearly separated in the CCA ordination diagram. The most important water quality variables for the fish occurrences in this river were pH, followed by temperature, conductivity, alkalinity and phosphate. Data analysis indicates that the occurrence of fishes were influenced by a combination of water quality parameters, but not associated with sampling month. The results present a new data from a study of fish assemblage and their habitat condition which may be important in fisheries activity and fish conservation of the river in the future.
Tropical peat swamp forest (PSF) is one of the most endangered ecosystems in the world. However, the impacts of
anthropogenic activities in PSF and its conversion area towards fish biodiversity are less understood. This study
investigates the influences of water physico-chemical parameters on fish occurrences in peat swamp, paddy field and
oil palm plantation in the North Selangor peat swamp forest (NSPSF), Selangor, Malaysia. Fish and water samples were
collected from four sites located in the peat swamps, while two sites were located in the paddy field and oil palm plantation
areas. Multivariate analyses were used to determine the associations between water qualities and fish occurrences in
the three habitats. A total of 1,382 individual fish, belonging to 10 families, 15 genera and 20 species were collected.
The family Cyprinidae had the highest representatives, followed by Bagridae and Osphronemidae. The most abundant
species was Barbonymus schwanefeldii (Bleeker 1854), while the least abundant was Wallago leerii Bleeker, 1851. The
paddy field and oil palm plantation area recorded significantly higher fish diversity and richness relative to peat swamp
(p<0.05). The water physico-chemical parameters, such as pH, DO, NH3
-N, PO4, SO4
, and Cl2 showed no significant
difference between paddy field and oil palm plantation (p>0.05), but was significantly different from the peat swamp
(p<0.05). However, no water quality parameter was consistently observed to be associated with fish occurrences in all
of the three habitats, but water temperature, NH3
-N, Cl2, SO4
, and EC were at least associated with fish occurrences in
two habitats studied. This study confirmed that each habitat possess different water quality parameters associated with
fish occurrences. Understanding all these ecological aspects could help future management and conservation of NSPSF.
A study on water quality and heavy metal concentration in sediment at selected sites of Sungai Kelantan was carried out. Ten water samples were collected along the river for physical and chemical analysis and twenty-six water and sediment samples were collected for heavy metal analysis. Water was sampled at three different dates throughout the study period whereas sediments were collected once. In addition to heavy metal analysis, sediment samples were also analysed for texture, pH and organic content. The physical and chemical water quality analyses were carried out according to the APHA procedures. Result of water quality analysis (physico-chemical) indicated that Sungai Kelantan is characterised by excellent water quality and comparable to pristine ecosystems such as the National Park and Kenyir Lake. This river was classified into class I – class III based on Malaysian interim water quality standard criteria (INWQS). Heavy metals Pb, Zn, Cu and Cd was detected at low concentration in sediment samples, except for Fe and Mn. The presence of Fe and Mn in sediment samples was though to be of natural origin from the soil. Anthropogenic metal concentrations in sediment were low indicating that Sungai Kelantan has not experienced extreme pollution.