排序方式: 共有14条查询结果,搜索用时 15 毫秒
1.
Geo-accumulation index and contamination factors of heavy metals (Zn and Pb) in urban river sediment 总被引:1,自引:0,他引:1
Hazzeman Haris Ley Juen Looi Ahmad Zaharin Aris Nor Farhanna Mokhtar Nur Ain Ayunie Ayob Fatimah Md. Yusoff Abu Bakar Salleh Sarva Mangala Praveena 《Environmental geochemistry and health》2017,39(6):1259-1271
The aim of the present study was to appraise the levels of heavy metal contamination (Zn and Pb) in sediment of the Langat River (Selangor, Malaysia). Samples were collected randomly from 15 sampling stations located along the Langat River. The parameters measured were pH, redox potential, salinity, electrical conductivity, loss of ignition, cation exchanges capacity (Na, Mg, Ca, K), and metal ions (Zn and Pb). The geo-accumulation index (I geo) and contamination factor (C f) were applied to determine and classify the magnitude of heavy metal pollution in this urban river sediment. Results revealed that the I geo of Pb indicated unpolluted to moderately polluted sediment at most of the sampling stations, whereas Zn was considered to be within background concentration. The I geo results were refined by the C f values, which showed Pb with very high C f at 12 stations. Zinc, on the other hand, had low to moderate C f values. These findings indicated that the sediment of the Langat River is severely polluted with Pb. The Zn concentration at most sampling points was well below most sediment quality guidelines. However, 40% of the sampling points were found to have a Pb concentration higher than the consensus-based probable effect concentration of 128 mg/kg (concentrations above this value are likely to cause harmful effects). This result not only highlights the severity of Pb pollution in the sediment of the Langat River, but also the potential risk it poses to the environment. 相似文献
2.
Praveena Sarva Mangala Syahira Asmawi Melati Chyi Josephine Liew Ying 《Environmental science and pollution research international》2021,28(15):18518-18522
Environmental Science and Pollution Research - Microplastics have been recognized as emerging pollutants with potential ecotoxicological impact. The contribution of washing machine use to... 相似文献
3.
Praveena Sarva Mangala Aris Ahmad Zaharin 《Environmental science and pollution research international》2021,28(45):63829-63836
Environmental Science and Pollution Research - This study examined the impacts of the Coronavirus disease 2019 (COVID-19) on the environment in the Southeast Asia region using qualitative content... 相似文献
4.
Influence of temperature and soil type on the toxicity of three pesticides to Eisenia andrei 总被引:1,自引:0,他引:1
P. Mangala C.S. De Silva Asoka Pathiratne Cornelis A.M. van Gestel 《Chemosphere》2009,76(10):1410-1415
Expansion of agriculture in the tropics has increased the use of pesticides that may affect the soil ecosystems. Few studies so far determined the effects of pesticides in the tropics and tropical risk assessment therefore often relies on data from temperate conditions. Hence we compared the toxicity of chlorpyrifos, carbofuran and carbendazim to the earthworm Eisenia andrei at two different temperatures reflecting temperate and tropical conditions. The toxicity of the three pesticides in both conditions decreased in the order carbendazim > carbofuran > chlorpyrifos. For chlorpyrifos and carbofuran, but not for carbendazim, survival was more sensitive at the higher temperature, probably due to increased earthworm activity. Sub-lethal effects (reproduction and growth) however, varied inconsistently with temperature and soil types. We conclude that toxicity of pesticides in tropics may not be predicted from data generated under temperate conditions, even within the same species. 相似文献
5.
Understanding of groundwater salinity using statistical modeling in a small tropical island,East Malaysia 总被引:1,自引:0,他引:1
Sarva Mangala Praveena Mohd Harun Abdullah Kawi Bidin Ahmad Zaharin Aris 《The Environmentalist》2011,31(3):279-287
This paper presents an understanding of groundwater salinity by identification of effective factors using chemometric methods
(cluster analysis and multiple linear regressions) in Manukan Island, Sabah. Local groundwater and environmental properties
were used to explore the effective factors of groundwater salinity. Cluster analysis showed salinity and chloride illustrated
the highest similarities. Electrical conductivity and total dissolved solids were also grouped in the same cluster. Seawater
is the only chloride source in groundwater of Manukan Island demonstrated an indication of seawater mixing in freshwater.
It is an effect of upward movement of the seawater by pumping activities. Precipitation and evapotranspiration (environmental
condition) with hydraulic heads were clustered together to show that they also influence salinity concentration in groundwater.
Multiple linear regressions showed descending order of the factors from chloride (the largest contribution) to evapotranspiration
(the smallest contribution) and illustrated the contribution to groundwater salinity in Manukan Island. The integrated results
using chemometric methods have provided a way to identify the effective factors on groundwater salinity. This similar approach
and resulting equation can be applied in other small tropical islands with alike hydrogeological condition and limited information
available for a better understanding of its groundwater salinity. 相似文献
6.
Mangala Yatawar Shihua Qi Odhiambo Joshua Owago Yuan Zhang Dan Yang Junpeng Zhang Julia E Burnet 《环境科学学报(英文版)》2010,22(2):314-320
In order to assess the contamination of edible marine organisms in Quanzhou and Xinghua Bays,Fujian Province,China,concentrations of organochlorine pesticides(hexachlorocyclohexane isomers or HCHs and dichlorodiphenyltrichloroethane isomers/derivatives or DDTs) and heavy metals(Cu,Pb,Zn,As,Cr,Cd,Ni and Hg) in 13 species collected from different sites in the bays were analyzed by GC-ECD and ICP-MS.The concentration of the sum of DDTs exceeded that the sum of HCHs in the samples.Most of the organisms showed h... 相似文献
7.
Liu Lin Han Jialiang Xu Xiaohang Xu Zhidong Abeysinghe Kasun S. Atapattu Anjana J. De Silva P. Mangala C. S. Lu Qinhui Qiu Guangle 《Environmental science and pollution research international》2020,27(34):42704-42712
Environmental Science and Pollution Research - Rice is frequently reported to be contaminated with heavy metals (HMs); thus, the human health risks from its consumption have received increasing... 相似文献
8.
Martin Moravčík Zuzana Sarvašová Ján Merganič Matej Schwarz 《Environmental management》2010,46(6):908-919
The article analyses the possibilities of developing an integrated indicator and a model of the assessment of forests naturalness
using the data from the database of mountainous spruce forests situated in the Western Carpathians of Slovakia. The article
presents two variants of such a model, one based on discriminant analysis, while the second one using an additive approach.
The analysis of the data from mountainous spruce forests revealed significant indicators of forest naturalness degree: the
arithmetic mean of the ratio between crown length and tree height, the deadwood volume, the coverage of grasses, the coverage
of mosses and lichens, and the aggregation index. In addition, the coefficient of variation of tree diameters was included
in the final model, since its presence in the model had a positive influence on the correctness of the classification of the
forest naturalness degree. The correctness of the classification of the proposed discriminant model was 74.5%. For the additive
model, the ranges of the values of the integrated indicator were defined for every degree of forest naturalness by taking
into account the error ranges of the arithmetic mean values and the percentiles of the values in individual degrees of forest
naturalness. The overall correctness of the classification with the additive model was 63.4%. In the second step, the scheme
how to apply the classification model of the forest naturalness degree in the decision-making process of designating as a
forest protected areas was proposed. In this scheme, the degree of forest naturalness is considered as a basic criterion for
the determination of nature-conservation value of forest ecosystems. As further decision-making criteria we identified the
possibility to restore, or the possibility to improve the naturalness of less natural forest ecosystems, which are designated
as protected; the occurrence of the endangered species; and the occurrence of other natural values. 相似文献
9.
10.
P. Mangala C.S. De Silva Asoka Pathiratne Cornelis A.M. van Gestel 《Environmental pollution (Barking, Essex : 1987)》2010,158(10):3041-3047
Effects of pesticides on structural and functional properties of ecosystems are rarely studied under tropical conditions. In this study litterbag and earthworm field tests were performed simultaneously at the same tropical field site sprayed with chlorpyrifos (CPF). The recommended dose of CPF (0.6 kg a.i. ha−1) and two higher doses (4.4-8.8 kg a.i. ha−1) significantly decreased litter decomposition during the first 3 months after application, which could be explained from lower earthworm and termite abundances during this period. Species-specific effects of CPF on organism abundance and biomass were observed, with termites being mostly affected followed by the earthworm Perionyx excavatus; the earthworm Megascolex sp. was least affected. Recovery was completed within 6 months. Decomposition in the controls and lowest two treatments was completed within 4 months, which suggests the need for modification of standard test guidelines to comply with faster litter degradation under tropical conditions. 相似文献