Mazlin Bin Mokhtar

Spatial water quality assessment of Langat River Basin (Malaysia) using environmetric techniques

This study investigates the spatial water quality pattern of seven stations located along the main Langat River. Environmetric methods, namely, the hierarchical agglomerative cluster analysis (HACA), the discriminant analysis (DA), the principal component analysis (PCA), and the factor analysis (FA), were used to study the spatial variations of the most significant water quality variables and to determine the origin of pollution sources. Twenty-three water quality parameters were initially selected and analyzed. Three spatial clusters were formed based on HACA. These clusters are designated as downstream of Langat river, middle stream of Langat river, and upstream of Langat River regions. Forward and backward stepwise DA managed to discriminate six and seven water quality variables, respectively, from the original 23 variables. PCA and FA (varimax functionality) were used to investigate the origin of each water quality variable due to land use activities based on the three clustered regions. Seven principal components (PCs) were obtained with 81% total variation for the high-pollution source (HPS) region, while six PCs with 71% and 79% total variances were obtained for the moderate-pollution source (MPS) and low-pollution source (LPS) regions, respectively. The pollution sources for the HPS and MPS are of anthropogenic sources (industrial, municipal waste, and agricultural runoff). For the LPS region, the domestic and agricultural runoffs are the main sources of pollution. From this study, we can conclude that the application of environmetric methods can reveal meaningful information on the spatial variability of a large and complex river water quality data.

Climate change and agricultural growth: an examination of the link in Malaysia

Purpose – The purpose of this paper is to identify and analyze the link between climate change and agricultural growth in Malaysia, and pursue three sub‐objectives: to determine and analyze the link between agricultural growth rate and climate change score; to determine and analyze the link between per capita CO2 emissions and agricultural production index; and to determine and analyze the link between per capita agricultural production index and per capita CO2 emissions.Design/methodology/approach – Relevant time series data compiled from several online sources including the Germanwatch, Ministry of Finance, Malaysia, and the United Nations database were used. The data for agricultural growth rate and climate change score for Malaysia were found to be available only for the four recent years from 2006 to 2009. The data for other variables such as per capita agricultural production index and per capita CO2 emissions have been standardized covering the period from 1990 to 2004. The ordinary least squares m...

Composition of heavy metals and airborne fibers in the indoor environment of a building during renovation

The renovation of a building will certainly affect the quality of air in the vicinity of where associated activities were undertaken, this includes the quality of air inside the building. Indoor air pollutants such as particulate matter, heavy metals, and fine fibers are likely to be emitted during renovation work. This study was conducted to determine the concentration of heavy metals, asbestos and suspended particulates in the Biology Building, at the Universiti Kebangsaan, Malaysia (UKM). Renovation activities were carried out widely in the laboratories which were located in this building. A low-volume sampler was used to collect suspended particulate matter of a diameter size less than 10xa0μm (PM10) and an air sampling pump, fitted with a cellulose ester membrane filter, were used for asbestos sampling. Dust was collected using a small brush and scope. The concentration of heavy metals was determined through the use of inductively coupled plasma–mass spectroscopy and the fibers were counted through a phase contrast microscope. The concentrations of PM10 recorded in the building during renovation action (ranging from 166 to 542xa0μgxa0mu2009−u20093) were higher than the value set by the Department of Safety and Health for respirable dust (150xa0μgxa0mu2009−u20093). Additionally, they were higher than the value of PM10 recorded in indoor environments from other studies. The composition of heavy metals in PM10 and indoor dust were found to be dominated by Zn and results also showed that the concentration of heavy metals in indoor dust and PM10 in this study was higher than levels recorded in other similar studies. The asbestos concentration was 0.0038 ± 0.0011xa0fibers/cc. This was lower than the value set by the Malaysian Department of Occupational, Safety and Health (DOSH) regulations of 0.1xa0fibers/cc, but higher than the background value usually recorded in indoor environments. This study strongly suggests that renovation issues need to be considered seriously by relevant stakeholders within the university in order to ensure that the associated risks toward humans and indoor environment are eliminated, or where this is not feasible, minimized as far as possible.