Dengan lafaz BISMILLAH..lakaran Warkah Pengikat HATI EMAS ini dimulakan..buat peringatan diri yang serba kekhilafan ini.
ALHAMDULILLAH.. Terima kasih Ya ALLAH atas nikmat Ihsan, Iman dan Islam anugerah teragungMU Ya ALLAH..
Puji dan puja kepada ALLAH SWT, TUHAN pemilik kata-kata yang benar, indah dan tersusun. Selawat dan salam kepada Nabi MUHAMMAD SAW yang apabila berkata-kata bukan daripada nafsu tetapi segala-galanya berpandukan wahyu. Lalu, kata-katanya sentiasa singkat dan tepat.
Ya ALLAH Ya RAHMAN Ya RAHIM..
Panjangkanlah usiaku..
agar lebih lama dapat aku mentaati-MU..
Jadikanlah kehidupanku ini sebagai ladang..
Moga di akhirat kelak ku mengutip hasilnya..
Ya ALLAH..
Tambahkanlah amalanku di saat bertambah usiaku..
Jadikanlah cahaya-MU bersinar menyinari jalanku..
Kalimah-MU zikirku..
sebagai tanda ingatanku pada-MU..
Ya ALLAH..
Jangan ENGKAU sia-siakan aku..
hamba yang sentiasa mengharap tempat rehat dan nikmat abadi..
Allahumma Aamiin Ya Rabbal 'Aalamiin.
===***===
Characterization of Spatial and Temporal Variability in Inner Western Johor Strait, Malaysia
Maznah Ismail, Noor Baharim Hashim and Ziba Kazemi
Faculty of Civil Engineering UTM Johor Bahru, Malaysia, 81310 UTM JB, Malaysia
Abstract
Charaterization of changes in inner Western Johor Strait (WJS) of monitoring works was sucessfully carried out. Eight water quality data sets collected in this area from Second Link to Causeway Link. We used an extensive dissolved oxygen (DO) data set to develop a statistically meaningful way of estimating mean DO from discrete measurements in inner WJS. Relationships among bottom water DO, vertical stratification, and the factors responsible for stratification-destratification in this narrow stretch of water along the WJS with some recent continuous monitoring data. Therefore, it is imperative that the environmental of reclamation and dredging works, municipal or industrial discharge, marine aquaculture and shipping activities in this area be effectively controlled and managed.
Introduction
Bottom hypoxia has emerged as one of the key environmental consequences of eutrophication in coastal areas worldwide. Its formation, severity, frequency and duration are governed not only by anthropogenic nutrient inputs, but also by a combination of physical, chemical and biological processes. This study focused mainly on physical parameters such as light penetration, spring versus neap tidal effect, and effect of water depth on bottom DO dynamics. The main parameters of water quality include temperature, salinity, dissolved oxygen and turbidity that are identified to effect on fish distribution (Blaber and Blaber, 1980). Sub stream heterogeneous, sediment characteristics, and also vegetation affect fish distribution through their influence on catch availability (Marchand, 1993) and protection from fisherman and predators (Blaber and Blaber, 1980).
Methods
Data from intensive surveys of WJS were made to establish 8 vertical profiling stations. The measurements in this study were made with Yellow Springs Incorporated (YSI) sensors and sondes. Vertical profiles was collected and identified by distance from Second Link to Causeway Link. All sampling stations were located at the middle of navigation channels. At each station, temperature, conductivity, salinity and DO were sampled at every one meter from surface to bottom during spring and neap tide.
Study Area
Johor Strait is located along the south shore of Peninsular Malaysia. Presently, there are land use activities for major development near the coastal zones of the Johor Strait. The land use regions generate both non point and point sources of contaminants. Metals, nutrients, industrial organic chemicals, and pesticides are the main contaminants in the Johor Strait because of the human activities in the agriculture and chemical industry sectors. As zone of vegetation are progressively utilized as agriculture and urban, it is significant to evaluate the impact of these changes in the water quality. The contamination of the natural environment by toxic chemicals could have bad impacts on the health of human and wildlife by way of bioaccumulation. Throughout the years, the coast of Johor Strait that acts as a boundary between Singapore and Malaysia is being polluted by contaminants from tributaries of the Sungai Melayu, Sungai Skudai, Sungai Bahan and Sungai Perpat (Azman et al., 2012).
Results and Discussion
Dissolved Oxygen (DO) is one of the essential environmental paramaters sustaining all aquatic life. DO has been traditionally used as one of the ecological indicators for examining any short-term water quality changes in the marine ecosystem (Engle et al., 1999).
Figure A
Vertical section of Dissolved Oxygen (DO)
with data collected at spring tide on March 1, 2012.
Figure A shows the typical structure along the Western Johor Strait. Each dot in the vertical section represents a point in a grid along the Western Johor Strait where dissolved oxygen (DO) measurements were made. From these data we calculated the area weighted mean DO.
Figure A shows higher DO in the surface layer and the low DO in the deeper layer near Causeway Link station area. Oxygen depletion occurs near Causeway Link, which are station WQ07 and WQ08. As shown in Figure A, DO concentration in surface layer is high but at the bottom layer become less than 2 mg/l because there is no any current of water near the stations. The presence of the causeway that has caused the blockage of the normal flow of the Western Johor Strait and led to the propagation of a standing wave with no flow at the causeway has aggravated the situation (Kuo, et al., 1991). However, in other stations from Second Link to Sungai Skudai estuary, the higher correlation in the upper layers is no doubt because those waters are uniformly responding to air fluxes that have large spatial scales.
Conclusion
While oxygen depletion is not the only environmental issue of concern along the Western Johor Strait (WJS), it is certainly one of the most important. There are potential links between low oxygen and kills of fish and commercially valuable shellfish. Field observations indicated that bottom DO concentrations decreased when neap tidal events occurred. Limited water exchange with open ocean in semi enclosed intertidal water of WJS which increased in flushing time and created a lot of anthropogenic pollutants via riverine inputs. In this period, stratification was still present and the vertical mixing was suppressed, which suggests that the DO supply in the bottom layer due to coastal water intrusion accompanied by estuarine circulation.
------
#ALHAMDULILLAH.. Allah Tempat Meminta..06-07-1437H | 14-04-2016M 09:52 KHAMIS
No comments:
Post a Comment