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21.
Noraini Mohd. Tamin Rozainah Zakaria Roslan Hashim Yu Yin 《Estuarine, Coastal and Shelf Science》2011,94(4):334-342
Avicennia marina saplings were established within a restoration area at Sg. Hj. Dorani, Malaysia between May and August 2010. Sapling establishment was achieved following the construction of segmented and hard breakwater as mitigating measure against coastal erosion. Geostructures known as brush faschines were installed within the restoration area as secondary sediment and seed traps. There was a steady increase in the sand content of the soil from 5% in November 2008 to 18% in May 2010. The dominant soil content was silt but it fluctuated and declined slightly over the same period, between 80% in November 2008 and 72% in May 2010. The accreting shoreline behind the breakwater had stabilised within 18 months. Subsequently, the first batch of A. marina wild seedlings or wildings was established on the mud surface in September 2009. Only about 10% of these wildings survived and showed high survival rate (90%) over the next eight months. Wildings that were naturally established near mother trees showed good growth performance. No wilding was established after the fruiting season in August 2010 as all seeds that were dispersed into the restoration area were washed away by September 2010. Tall, A. marina wild saplings (1 m) planted within the restoration area showed higher survival rate (80%) compared to planted saplings of Rhizophora apiculata (30%). Final planting of a thousand 1 m tall A. marina wild saplings was carried out from June 2010, in clumps of 20 and in 1 m × 1 m spacing. By the end of September 2010 clusters of regenerating A. marina mangroves about 1.5 m tall were successfully established on the accreting coastline. 相似文献
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A study on water quality of the two long-logged and abandoned headwaters in Temengor Reservoir was conducted to determine their natural recovery.In this study,we used National Water Quality Standards for Malaysia prepared by Malaysian Department of Environment as an indicator for water quality recovery.The parameters measured were dissolved oxygen（mg/L）,water temperature（℃）,pH,conductivity（mS/cm）,total dissolved solids（mg/ L）,water velocity（m/s）,ortho-phosphate（PO4-P）,nitrite-nitrogen（NO2-N）,nitrate-nitrogen（NO3,-N）and alkalinity. In general,water quality in Sungai Enam and Sungai Telang were in ClassⅠ,indicating water quality in both streams have recovered.Based on the t-test,Sungai Enam and Sungai Telang differed significantly in all parameters except for dissolved oxygen,NO2-N and NO3-N.In spatial analyses（upper,middle and lower reaches comparisons）, the two-way ANOVA analysis shows that there were significant differences in all studied parameters between the two rivers except for dissolved oxygen,total dissolved solids,NO2-N and NO3-N.Stream flow,hydrologic pathways,geomorphology,physical and environmental characteristics are essential elements in understanding the dynamics of water systems in Sungai Enam and Sungai Telang.Due to the recovery,these two headwaters are thus suitable for fish conservation and restoration sites. 相似文献
23.
M. F. Tajul Baharuddin A. R. Othman S. Taib R. Hashim M. H. Zainal Abidin M. A. Radzuan 《Environmental Earth Sciences》2013,69(8):2779-2797
Freshwater lenses are vital to small island communities but are susceptible to seawater intrusion due to the physical changes in the shoreline land cover. The effect of seawater intrusion and irrigation water on a coastal unconfined aquifer beneath naturally preserved mangrove and deforested mangrove-barren belt was investigated in Carey Island. Analysis of the total dissolved solids (TDS) and earth resistivity (ER) using a geochemistry-electrical integrated technique gave a TDS–ER relationship capable of predicting freshwater lens morphology affected by sea-irrigation water. The study result shows freshwater was fourfold thicker in close proximity of the mangrove forest than the mangrove barren area; the further the shoreline from the mangrove thickest section, the less vulnerable was the seawater intrusion and the more fresh the irrigation water, and hence the greater the freshwater availability potential. 相似文献
24.
Bhadravathi Eswara Lokesh Zubaidah Aimi Abdul Hamid Takamitsu Arai Akihiko Kosugi Yoshinori Murata Rokiah Hashim Othman Sulaiman Yutaka Mori Kumar Sudesh 《洁净——土壤、空气、水》2012,40(3):310-317
Utilization of cheap renewable carbon feedstock for polyhydroxyalkanoate (PHA) production not only brings down its production cost but also ensures sustainability. The scope of this study was to evaluate the potential of sap extracted from felled oil palm trunk (OPT) as a novel inexpensive renewable carbon source for PHA production. OPT sap was found to be nutritionally rich and contained various fermentable sugars (5.5% w/v) as its major constituent. Termite gut isolate, Bacillus megaterium MC1 grew profoundly in mineral medium with OPT sap as carbon source and a cell density of 10.9 g/L was attained after 16 h of cultivation in shake flask cultures. A maximum poly‐3‐hydroxybutyrate [P(3HB)] content (% cell dry weight; CDW) of 30 wt% and a P(3HB) concentration of 3.28 g/L was recorded. Additionally, OPT sap extracted from younger tree trunks with prolonged storage had higher sugar content (10.8% w/v) and, when used as a growth medium without the addition of any nutrients, supported bacterial growth comparable to commercially available media. 相似文献
25.
Mapping of regional potential groundwater springs using Logistic Regression statistical method 总被引：1，自引：0，他引：1
Jalal?ZandiEmail author Pezhman?Taherei?Ghazvinei Roslan?Hashim Khamaruzaman?Bin?Wan?Yusof Junaidah?Ariffin Shervin?Motamedi 《Water Resources》2016,43(1):48-57
Increasing demand for fresh water extraction in the semi-arid regions necessitates the exploration of groundwater spring potential areas notwithstanding the importance of both conservation and management aspects for planning development. Potential map of groundwater springs reduces the costs of horizontal well drilling that provides useful tool for engineers to locate probable region for groundwater existence. The objective of this study is to establish a model of the potential map of groundwater spring occurrences. A statistical and probabilistic Logistic Regression (LR) model was developed in association with the specified spring location and effective occurrence factors. The most statistically significant effective factors on spring occurrences were selected to zone groundwater spring potential areas. The proposed model was evaluated statistically. Results showed a satisfactory prediction for the proposed model. The outcome of this study facilitates the low-cost utilization of groundwater resources when policy makers need strategic development planning. 相似文献
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27.
Hashim Bassim Mohammed Al Maliki Ali Alraheem Esam Abd Al-Janabi Ahmed Mohammed Sami Halder Bijay Yaseen Zaher Mundher 《Theoretical and Applied Climatology》2022,148(3-4):881-898
Theoretical and Applied Climatology - Iraq is classified as the fifth most vulnerable country in the world to decreased water and food availability, extreme temperatures, and associated health... 相似文献
28.
This research developed an approach to enable the discrimination of lithological units and detection of host rock of chromitite bodies within ophiolitic complexes using the advanced spaceborne thermal emission and reflection radiometer (ASTER) and Landsat thematic mapper (TM) satellite data. Three main ophiolite complexes located in southern Iran were selected for the study. A specialized band ratio (4/1, 4/5, 4/7) of ASTER, minimum noise fraction (MNF) components and spectral angle mapper (SAM) on ASTER and Landsat TM data were used to distinguish ophiolitic rock units. Results show that the specialized band ratio was able to identify different rock units and serpentinized dunite as host rock of chromitites within ophiolitic complexes. Minimum noise fraction components of ASTER and Landsat TM data are suitable for distinguishing ophiolitic rock complexes at a regional scale. The integration of SAM and feature level fusion used in this investigation discriminated the ophiolitic rock units and provided geological map for the study area, including identification of high potential areas (serpentinite dunite) for chromite exploration targets. 相似文献
29.
Hashim Almalki Abdel-Khalek El-Werr Kamal Abdel-Rahman 《Arabian Journal of Geosciences》2011,4(7-8):1131-1150
Eight shallow seismic refraction profiles were conducted at the proposed KACST expansion site, northwest of Riyadh, to estimate the near-surface geotechnical parameters for construction purposes. Both compressional (P) and shear (S) waves were acquired, processed, and interpreted using “time-term” technique which is a combination of linear least squares and delay time analysis to invert the first arrivals for a velocity section. The most important geotechnical near-surface parameters such as stress ratio, Poisson’s ratio, material index, concentration index, N value, and foundation material-bearing capacity are calculated. The results of these seismic measurements were compared with the results of borehole report in the project area in terms of number of layers, the lithological content, thicknesses, and N values of rock quality designation. A good matching between the results was observed particularly at the sites of boreholes. 相似文献
30.
Zarul Hazrin Hashim Asmah Patiroi Mashhor Mansor Shahrul Anuar Md. Sah Donald C. Jackson 《湿地科学》2011,9(4):314-321
A study on physico-chemical dynamics of Temengor Reservoir was conducted to determine whether headwaters and seasonal changes play a major role in regulating physico-chemical dynamics of Temengor Reservoir. Temengor Reservoir receives water from its surrounding water catchments and headwaters. Then, the water flows into a series of hydroelectric dams, namely the Bersia, Kenering and Chenderoh dams. Generally, water quality in Temengor Reservoir can be classified as Class I. Physico-chemical trends showed that water quality in euphotic zone of Temengor Reservoir is stable and consistent. Two-way ANOVA analyses showed that seasonal variations only affected water temperature, Secchi disc’s depth and nitrate-nitrogen. Based on Tukey’s post-hoc test, all three headwaters in this study exert no influence to the reservoir’s water quality. These insignificant differences were probably due to water temperature and the size of the headwaters and the reservoir itself. In situ parameters profiling showed that the epilimnion zone in Temengor Reservoir is from the surface to 6 m depth, the metalimnion zone is from 6 m to 12 m depth and the hypolimnion zone is from 12 m depth onwards to the bottom of the reservoir. Thus, continuous water profiling monitoring that covers high and low water levels need to be conducted to determine characteristics of the physico-chemical dynamics in the water column and also to analyse changes in reservoir layers. Through these studies, discontinuity trends in the Perak River could be determined and suggestions to the respective agencies could be made to conserve and to sustain downstream biodiversity. 相似文献