16 research outputs found
Water quality index for the Skudai River and its tributaries for identifying the problematic areas for better watershed management
It is very important to develop a rehabilitation plan for the watersheds that have been degraded because of increased development activities and high urbanization. Identifying the most vulnerable parts of a watershed is challenging and can be done if water quality in the river was determined in different sections from the upstream to the downstream of a watershed. In this study, we delineated the Skudai River watershed into 25 sub-watersheds using ArcGIS technique. Later, we identified tributaries in each sub-watershed. The subwatersheds were grouped into three main categories, i.e. natural, semi-urban, and urban subwatersheds depending on land use patterns. Water quality samples were collected at different tributaries from all three categories of sub-watersheds. The paper presents water quality analysis results. The Skudai River (natural part) was classified into natural sub-watershed as this sub-watershed was dominated with natural forest. The Senai and Kempas rivers were classified into sub-urban watersheds while Melana and Danga rivers were classified into urban watersheds. The water quality index (WQI) for the Skudai River (Natural) was 95.2 and falls in Class I category, i.e. clean. The Senai River had WQI of 84.5 and Class II category, i.e. slightly polluted. However, Kempas River which was also in the sub-urban watershed had calculated WQI of 54.5, in Class III and polluted. Melana River was also polluted river with WQI of 68.8 (Class III). The Danga River was also polluted river with WQI value as 55.2. Water quality in the direction of flow in the Skudai River was deteriorating because of some local pollutants entry on the way
Operational efficiency and up-coning problem of scavenger wells in lower Indus Basin of Pakistan
Groundwater in lower Indus Basin of Pakistan is available in thin aquifers. Abstraction of fresh groundwater can cause up-coning and ultimately degrade water quality in the freshwater aquifer. Up-coning is the saline water intrusion in the freshwater aquifer. Once quality of freshwater is deteriorated because of up-coning, it is very hard to make it again fit for irrigation usage. Thus, it is always advised to abstract groundwater on sustainable level without affecting freshwater aquifer permanently. In this study, we have investigated the operational efficiency of 79 scavenger wells installed at right side of Jamrao canal, lower Indus Basin, Pakistan to check whether these wells were performing with the design operational efficiency. We found that majority of scavenger wells were running quite below the design operational efficiency. The combined operational efficiency of freshwater and saline pumps was 34.3%. The operational efficiency of saline water pumps was slightly higher (37.7%) than the freshwater water pumps (30.7%). We also performed a constant rate pumping test on one of the scavenger wells (i.e. JRS-36) to check whether any chances of up-coning were happening if the both pumps (freshwater and saline water) of the selected scavenger well were operational. The pumping test revealed that chances of up-coning were negligible if the pumps were run within the design operational hours (14.4 h per day)
Effect of irrigation and nitrogen levels on the growth and yield of wheat
A field experiment was carried out to evaluate the effect of irrigation regimes and nitrogen levels on the growth and yield of wheat cv. Kanchan (Triticum aestivum L.). The experiment includes two factors such as four irrigation regimes and four nitrogen levels. Three farmer’s fields were selected for experimentation as replication. Yield and yield contributing factors were significantly affected by irrigation regimes and different doses of nitrogen. Maximum grain yield of 2.27 t ha−1 by the application of 200 mm irrigation treatment. Interaction between 200 mm irrigation and 120 kg N ha−1 was the best combination treatment
Removal of scale deposition on pipe walls by using magnetic field treatment and the effects of magnetic strength
Scale deposition on pipe walls is prevalent in water distribution systems and is difficult to remove. Commonly, chemical treatment is applied to remove the hard scale. However, it is detrimental to users' health and causes adverse environmental impacts. The need for clean water production for potable and other applications is essential. This study shows the application of magnetic water treatment as a safe and effective method for scale removal in water purification. Permanent magnets were installed in the designed treatment devices that consisted of pipes with scale deposition and the effect of magnetic field on scale reduction was monitored. The scale removal efficiency was evaluated based on calcium concentration in the outlet, after passing through the magnetic field. Magnetic strength was varied between 0.1 T to 0.4 T to investigate its effect on scale reduction. The morphology were analyzed by field emission scanning electron microscope. It was found that magnetic field enhanced scale removal from pipe walls by 46.7%. With respect to the increasing the magnetic field strength to 0.4 T, the efficiency of removal also increased to 30%. Possible mechanisms involved in the magnetic treatment that affects scale reduction such as the effect of magneto-hydrodynamics and magnetically modified hydration are discussed. Magnetic technology is a simple, cost-effective and environmentally friendly treatment approach for clean water production with significant scale removal efficiency. Magnetic treatment can be used either as a stand-alone technology or in water purification systems
Użycie wielu kryteriów do wyboru najbardziej wrażliwej zlewni w projektowaniu planu zarządzania
Listing of watershed management goals/targets is one of the integral parts of the management plan for
a watershed. In this paper, we have listed 18 watershed management targets for which the Malaysian watersheds
could possibly be managed in future. Based on the listed watershed management targets, the priority ranking of
18 targets is developed from the relative importance weights obtained from a survey conducted from 29 stakeholders.
Three weighting methods (SWING, SMART, and SMARTER) were applied to elicit weights. We found
that the SMART (Simple Multi-Attribute Rating Technique) weighting method was a favorable method for eliciting
stable sets of weights for the watershed management targets. The SWING weighting method produces better
weights than the SMARTER method. The listed watershed management targets will assist watershed managers
and decision makers in decision making to use available resources (e.g. water quality, land-use, groundwater,
and many other resources) in a more efficient and sustainable manner. The efficient utilization of all resources
within a watershed will ultimately save watersheds (more specifically the urbanized watersheds) from further
deterioration caused by unchecked infrastructure development activities.Określenie celów zarządzania zlewnią jest jedną z integralnych części planu zarządzania. W prezentowanej
pracy ustalono 18 celów, do których w przyszłości zmierzać będzie zarządzanie zlewniami Malezji. Na podstawie
tych celów ustalono ranking priorytetów, stosując wagi względnego znaczenia uzyskane w wyniku ankietowania
29 udziałowców. Dla uzyskania wag zastosowano trzy metody ważenia (SWING, SMART i SMARTER).
Stwierdzono, że metoda SMART (Simple Multi-Attribute Rating Technique) była przydatna do ustalenia zestawu
wag dla poszczególnych celów zarządzania zlewnią. Wagi ustalone metodą SWING były bardziej przydatne
niż ustalone metodą SMARTER. Uporządkowana lista celów zarządzania będzie pomocna zarządcom i decydentom
w podejmowaniu decyzji o wykorzystaniu dostępnych zasobów (jakość wody, użytkowanie ziemi, wód
podziemnych i innych) w sposób bardziej efektywny i zrównoważony. Efektywne użytkowanie wszystkich zasobów
zlewni uchroni je (szczególnie zlewnie zurbanizowane) od dalszego pogorszenia jakości wskutek niekontrolowanego
rozwoju infrastruktury w przyszłości
Identification of vulnerable areas to floods in Kelantan River sub-basins by using flood vulnerability index
Flood vulnerability indices for the Kelantan River sub-basins were developed from various flood-related variables. The vulnerability indices of the Kelantan River sub-basins involved flood depth-inundation area, soil erosion potential, and potential of soil for agricultural use, population vulnerability, road infrastructure vulnerability and market infrastructure vulnerability. These indices were developed from the use of Geographic Information System (GIS) technique. The result indicates that the flood vulnerability indices of sub-basins were mostly ranked high in the areas with high concentration of development activities and densely populated region with large infrastructure existence that are more flood-prone group than others especially in major metropolitan areas. In order to steer against probable damage caused by flood, it remains important to develop a tool that is most beneficial for river basin managers and policy makers, so that they can conduct vulnerability assessment and flood risk in term of human lives losses and property damages during future massive floods. The output of this study can guide decision makers to reduce flood risks Kelantan River basin in future