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1.
Nader Saadatkhah Mohammadreza Hadad Tehrani Shattri Mansor Zailani Khuzaimah Azman Kassim Reza Saadatkhah 《Arabian Journal of Geosciences》2016,9(17):687
In the current years, changing the land cover/land use had serious hydrological impacts affecting the flood events in the Kelantan River basin. The flood events at the east coast of the peninsular Malaysia got highly affected in the recent decades due to several factors like urbanisation, rapid changes in the utilisation of land and lack of meteorological (i.e. change in climate) and developmental monitoring and planning. The Kelantan River basin has been highly influenced due to a rapid change in land use during 1984 to 2013, which occurred in the form of transformation of agricultural area and deforestation (logging activities). In order to evaluate the influence of the modifications in land cover on the flood events, two hydrological regional models of rainfall-induced runoff event, the Hydrologic Engineering Center (HEC)-Hydrologic Modeling System (HMS) model and improved transient rainfall infiltration and grid-based regional model (Improved TRIGRS), were employed in this study. The responses of land cover changes on the peak flow and runoff volume were investigated using 10 days of hourly rainfall events from 20 December to the end of December 2014 at the study area. The usage of two hydrological models defined that the changes in land use/land cover caused momentous changes in hydrological response towards water flow. The outcomes also revealed that the increase of severe water flow at the study area is a function of urbanisation and deforestation, particularly in the conversion of the forest area to the less canopy coverage, for example, oil palm, mixed agriculture and rubber. The monsoon season floods and runoff escalate in the cleared land or low-density vegetation area, while the normal flow gets the contribution from interflow generated from secondary jungle and forested areas. 相似文献
2.
Norazlina Ab Halim Faradiella Mohd. Kusin Khairul Nizam Mohamed 《International Journal of Environmental Science and Technology》2018,15(4):733-742
This study was carried out to determine the concentration of heavy metals (Cd, Ni, Pb, Cr, Ni and Zn) in ordinary Portland cement (OPC) produced from the co-processing with hazardous waste in comparison with OPC produced using natural raw materials. The results showed that the concentration of heavy metals in cement produced from natural raw material was in the order of Zn > Pb > Cr > Ni > Cu > Cd. Zn and Cd were the highest and the lowest concentrations, respectively, in cements produced from the co-processing activity. The difference between heavy metals concentrations in OPC produced with and without co-processing was found to be statistically significant. The concentration of heavy metals in the cement produced is generally factory dependent. The human risk assessment associated with the heavy metals for non-carcinogenic and carcinogenic risks has been evaluated. The calculated hazard index (HI) and total lifetime cancer risks (LCR) were lower than the acceptable threshold reference values, HI < 1 and LCR < 1 × 10?4, respectively. Thus, it is anticipated that there is no potential of non-carcinogenic and carcinogenic risks for both adult and children. However, the findings indicated that there is a need for regulatory monitoring. The exposure pathway for both non-carcinogenic and carcinogenic risks are both in the order of ingestion > dermal > inhalation. 相似文献
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Sheng Hua Tan Shi Wei Wong Du Jia Chin Min Lee Lee Ying Hui Ong Siaw Yah Chong Azman Kassim 《Environmental Earth Sciences》2018,77(16):589
Rainfall-induced landslide is a common geohazard in tropical and humid regions. Capillary barrier system (CBS) is a popular and widely studied mitigating measure for rainfall-induced landslides. However, several previous studies have shown that the performance of the conventional CBS under intense rainfalls has not been particularly convincing. This paper aims to explore the feasibility and effectiveness of a newly proposed system, known as “biomediated capillary barrier system” (B-CBS) in minimizing water infiltration into soil. A one-dimensional soil column was used to investigate the infiltration characteristics of the proposed system. The results showed that the B-CBS of biomediated residual soil overlying original residual soil (Test IV) could effectively control the infiltration into soil by taking advantage of the less-permeable biomediated soil cover. The B-CBS of biomediated residual soil overlying gravelly sand (Test V) and the three-layered B-CBS of fine sand overlying gravelly sand and biomediated residual soil (Test VI) showed the best performance in terms of minimizing the water infiltration. A suction of about 5 kPa still remained in the soil column after 60 min of infiltration from the ponded water on the soil surface. 相似文献
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Uplift response of symmetrical anchor plates with and without grid fixed reinforced （GFR） reinforcement was evaluated in model tests and numerical simulations by Plaxis. Many variations of reinforcement layers were used to reinforce the sandy soil over symmetrical anchor plates. In the current research, different factors such as relative density of sand, embedment ratios, and various GFR parameters including size, number of layers, and the proximity of the layer to the symmetrical anchor plate were investigated in a scale model. The failure mechanism and the associated rupture surface were observed and evaluated. GFR, a tied up system made of fiber reinforcement polymer （FRP） strips and end balls, was connected to the geosynthetic material and anchored into the soil. Test results showed that using GFR reinforcement significantly improved the uplift capacity of anchor plates. It was found that the inclusion of one layer of GFR, which rested directly on the top of the anchor plate, was more effective in enhancing the anchor capacity itself than other methods. It was found that by including GFR the uplift response was improved by 29%. Multi layers of GFR proved more effective in enhancing the uplift capacity than a single GFR reinforcement. This is due to the additional anchorage provided by the GFR at each level of reinforcement. In general, the results show that the uplift capacity of symmetrical anchor plates in loose and dense sand can be significantly increased by the inclusion of GFR. It was also observed that the inclusion of GFR reduced the requirement for a large L/D ratio to achieve the required uplift capacity. The laboratory and numerical analysis results are found to be in agreement in terms of breakout factor and failure mechanism pattern. 相似文献
5.
Mohd Khairul Nizar Shamsuddin Wan Nor Azmin Sulaiman Saim Suratman Mohamad Pauzi Zakaria Kamarudin Samuding 《Arabian Journal of Geosciences》2014,7(9):3731-3753
The bank infiltration (BI) technique may be a viable option if the local climate, hydrological, and geological conditions are conducive. This study was specifically conducted to explore the possibility of using BI to source the polluted surface water in conjunction with groundwater. Three major factors were considered for evaluation: (1) investigation on the contribution of surface water through BI, (2) input of local groundwater, and (3) water quality characteristics of water supply. Initially, the geophysical method was employed to define the subsurface geology and hydrogeology, and isotope techniques were performed to identify the source of groundwater recharge and interaction between surface water and groundwater. The physicochemical and microbiological parameters of the local surface water bodies and groundwater were analyzed before and during water abstraction. Extracted water revealed a 5 %–98 % decrease in turbidity, as well as HCO3 +, SO4 ?, NO3 ?, Al, As, and Ca concentration reduction compared with those of Langat river water. However, water samples from test wells during pumping show high concentrations of Fe2+ and Mn2+. In addition, amounts of Escherichia coli, total coliform, and Giardia were significantly reduced (99.9 %). Pumping test results indicate that the two wells (DW1 and DW2) were able to sustain yields. 相似文献
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I. A. Al-Baldawi S. R. S. Abdullah N. Anuar I. Mushrifah 《International Journal of Environmental Science and Technology》2017,14(1):75-84
The development of the bioaugmentation during the phytoremediation of contaminated water with diesel in pilot horizontal subsurface flow constructed wetlands was investigated for 63 days. The objective of this study was to examine the enrichment of rhizobacteria in a pilot-scale system for efficient treatment of total petroleum hydrocarbon (TPH) effluent. A consortium of three rhizobacteria strains (Bacillus aquimaris, Bacillus anthracis and Bacillus cereus), which were able to utilize hydrocarbon compounds as sole carbon sources, was injected into the constructed wetlands (batchwise operation) planted with Scirpus grossus. The TPH removals from water, without or with the addition of rhizobacteria, were found to be 72 and 84%, while from sand was found to be 59 and 77%, for each treatment, respectively. These results showed that the rhizobacteria strains could enhance S. grossus growth by decreasing diesel stress and protecting S. grossus against diesel, with 12 and 18% additional TPH removal from water and sand, respectively. Our results demonstrate that S. grossus is potential to improve the phytoremediation of hydrocarbon contaminants through inoculation with effective rhizobacterial strains. 相似文献
9.
Ahmed?I.?RushdiEmail author Tarek?A.?T.?A.?Kassim Bernd?R.?T.?Simoneit 《Environmental Geology》2009,58(8):1675-1687
Sediment samples from the coastal zone of the Gulf of Suez contain a variety of organic compounds from anthropogenic and natural
sources. A total of 12 surface samples of bottom sediments were collected with an Ekman grab sampler along an off-shore transect
south of Ras Abu el-Darag. The samples were extracted with a mixture of dichloromethane and methanol (3:1 v/v) after drying
and sieving through 250 μm mesh. The extracts were derivatized and analyzed by gas chromatography–mass spectrometry in order
to characterize the chemical composition and sources of the organic components. Marine with minor terrestrial biota were the
major natural sources of organic tracers and included n-alkanoic acids, sterols and saccharides (5.7–76.7%). Anthropogenic sources, from petroleum related activities, detergent
usage for spill cleaning and littering, are indicated by the presence of n-alkanes with carbon preference index ≤1.0, hopanes, steranes, unresolved complex mixture of branched and cyclic hydrocarbons,
alkyl nitriles, alkamides and plasticizers. Their total relative concentrations ranged from 23.3 to 97.3% of the total extracts.
Petroleum residues from natural seepage may also be part of these hydrocarbons. The levels of anthropogenic inputs decrease
from about 94% in coastal zone sediments to about 20% in sediments from the reef front. 相似文献
10.
Amir Shah Ruddin Md Shah Mashhor Mansor Shahrul Anuar Mohd Shah Che Salmah Mohd Rawi Abu Hassan Ahmad Ibrahim Jaafar 《湿地科学》2008,6(1):34-44
A survey was carried out at the largest rice cultivation area in Peninsular Malaysia,the Muda rice agroecosystem.The main objective of this study was to document the overall biodiversity associated with this unique agroecosystem by using a combination of sampling techniques in order to record different groups of fauna and flora.The total number of biota recorded and identified from the rice field ecosystem during the study period consisted of 46 species of zooplankton,81 species of aquatic insects,5 species of rodents,7 species of bats,87 species of birds,11 species of fishes and 58 species of weeds.A long-term study should be carried out as more species are expected to be recorded when more of the Muda rice agroecosystem area has been sampled to obtain sufficient information on the Muda rice agrobiodiversity. 相似文献