Environmental Engineering
R. Pramana; B.Y. Suprapto; Z. Nawawi
Abstract
BACKGROUND AND OBJECTIVES: Land-based aquaculture operations, at present, are intensively conducted to meet the ever-growing demand for food consumption. Floating net cages are one of the traditional methods commonly used by Indonesian fishermen for river fish farming. Increased human activities ...
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BACKGROUND AND OBJECTIVES: Land-based aquaculture operations, at present, are intensively conducted to meet the ever-growing demand for food consumption. Floating net cages are one of the traditional methods commonly used by Indonesian fishermen for river fish farming. Increased human activities along the Musi River and coastline have resulted in pollution and waste in the river waters and fluctuating water quality. Yet, floating net cage owners still manually assess the water quality. This study aims to develop an early warning system for water quality and create a decision-making program as a reference for fishermen to relocate floating net cages when the river water quality deteriorates.METHODS: The device was tested at 39 locations within a radius of approximately 3400 meters, and the distance between locations varied between 55 and 334 meters. The river was divided into three sections: the river coast, the middle section, and the other river coast. Water quality sensors were placed at a depth of 0–20 centimeters from the surface of the Musi River, with measurement durations at each location ranging from 1 to 40 minutes. Direct measurements of the Musi River's water quality were obtained by monitoring the water quality using an internet-based computer application. A decision-making Python program utilizing fuzzy logic was then executed to evaluate the suitability of the river water quality for fish cultivation. The program's input variables comprise water temperature, potential of hydrogen, and dissolved oxygen sensor data. Meanwhile, the program output recommends floating net cage owners to either "Stay in position" or "Move." Water quality warnings that exceed the upper and lower threshold limits are displayed using light-emitting diode indicators and a buzzer.FINDINGS: Overall, the water quality values of the Musi River at the test locations generally indicated stable and suitable conditions for river fish cultivation. The average water quality values were 29.20 degrees Celsius for temperature, 3.98 milligrams per liter for dissolved oxygen, and a potential of hydrogen of 6.42. From all the data obtained during the decision-making program, 36 locations suggested that the floating net cages should "Stay in position." Meanwhile, the three remaining locations were recommended to "Move" as they exhibited poor water quality, with potential of hydrogen values below 6. Field observations indicated that these locations were situated near residential areas, factories/industries, and tributaries, which are highly susceptible to waste and pollution. The output of the decision-making program correlated with the issued warnings by the water quality warning indicators when the pH value exceeded the lower threshold limit.CONCLUSION: The fuzzy logic method implemented in the Python program for decision-making regarding the relocation of floating net cages in river fish farming revealed the fluctuating water quality conditions of the Musi River within a specific time duration. These conditions correlated with the proximity of the water bodies to pollution sources such as residential areas, factories, and tributaries. The program's output classified the status of the floating net cages into two conditions: "Stay in position" or "Move." The decision-making application to relocate floating net cages for fish farming in rivers provides a solution for fishermen as the resulting program decisions give the same indication as the reading value of the water quality sensor.
Environmental Engineering
F.M. Torres-Bejarano; M. Verbel-Escobar; M.C. Camila Atencia-Osorio
Abstract
BACKGROUND AND OBJECTIVES: One of the negative impacts of polluting activities on aquatic ecosystems is the loss of its natural self-purification ability, for this reason, the purpose of this research was to evaluate the Sinú river capacity to assimilate wastewater discharges.METHODS: Monitoring ...
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BACKGROUND AND OBJECTIVES: One of the negative impacts of polluting activities on aquatic ecosystems is the loss of its natural self-purification ability, for this reason, the purpose of this research was to evaluate the Sinú river capacity to assimilate wastewater discharges.METHODS: Monitoring of several water quality parameters was carried out in the river at different seasons and a numerical method was used to simulate different scenarios through the Environmental Fluid Dynamics Code model. The model calibration process was tested applying the Root Mean Square Error and after calibrating the model, scenarios of increase and decrease of discharge concentrations and flows, and river flows were simulated. Finally, the results were compared to water quality reference limits.FINDINGS: Results show that the model accurately represented the real conditions of the studied river section for all the evaluated parameters. Also, assimilative capacity was affected mostly by the scenario in which the river flow was decreased by 50%, and the flows and discharges concentrations were increased five times; causing parameters such as ammonia nitrogen, chemical oxygen demand, phosphates, and total nitrogen, to exceed the established reference limits with maximum concentrations of 2.7 mg/L, 30.9mg/L, 0.98 mg/L and 6.3 mg/L; respectively. Higher concentrations of water quality parameters were mostly found in the dry season since lower velocities and river flows promote less pollutants mixing and dilution processes.CONCLUSION: The model spatiotemporal simulations showed the effect of the wastewater discharges on the Sinú River assimilative capacity and made it possible to find those scenarios where water quality parameters exceeded the reference limits, becoming an essential tool for water management and the development of strong water quality objectives by stakeholders and environmental authorities.
Environmental Engineering
Suhaemi .; D.G. Bengen; C.P.H. Simanjuntak; A.F. Koropitan
Abstract
BACKGROUND AND OBJECTIVES: The Misool Islands are lined up regularly from west to east, the southern part of Raja Ampat Archipelago, Papua - Indonesia. The geomorphology is distinctive, and the coral reef substrate causes turbulence. Misool waters are located in the Papuan bird's head seascape, passed ...
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BACKGROUND AND OBJECTIVES: The Misool Islands are lined up regularly from west to east, the southern part of Raja Ampat Archipelago, Papua - Indonesia. The geomorphology is distinctive, and the coral reef substrate causes turbulence. Misool waters are located in the Papuan bird's head seascape, passed by Pacific water masses. The assessment status of Misool waters as a conservation area does not include hydrodynamic aspects in the decision processes. The present study is fundamental for determining and changing essential areas for conservation. The main objective of this study is to the pattern of hydrodynamic processes and investigate the features of the water mass in the Misool waters.METHODS: An acoustic doppler current profiler was deployed to measure currents every 15 minutes for ten water column layers. Investigation of waters characteristics was using Conductivity-Temperature-Depth equipment. A three-dimensional computational model was performed using MIKE3.FINDINGS: The water mass around the Misool Islands are more influenced by the local oceanographic processes than the water masses from the Pacific Ocean. The study site is characterized by the mixed tide, prevalence to semi-diurnal based on observational tidal data. Wind and baroclinic properties generate non-significant currents, resulting in low horizontal and vertical stratification. Intensification of tidal currents occurs along the shallow part in northeastern and part of the channel between Misool Islands and the mainland of Papua.CONCLUSION: The interaction of barotropic tides, geomorphology, and coral reef triggers the unstratified water mass. Strong currents and turbulence on the northeast side produce homogeneous waters. The water mass in Misool waters is originated from the local dynamic.
Environmental Engineering
M. D. Enriquez; R. M. Tanhueco
Abstract
BACKGROUND AND OBJECTIVES: Safeguarding water resources became a major concern in many parts of the world as it aims to provide safe and healthy water for humans. Water quality monitoring is a popular tool in ensuring water quality is safe and within the allowable limits and standards for the health ...
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BACKGROUND AND OBJECTIVES: Safeguarding water resources became a major concern in many parts of the world as it aims to provide safe and healthy water for humans. Water quality monitoring is a popular tool in ensuring water quality is safe and within the allowable limits and standards for the health of the community. To provide interventions and strategies for the rehabilitation, a water quality monitoring plan was conducted to describe the water quality and the classification of the river.METHODS: This study conducted an environmental analysis to determine existing conditions and processes in the surrounding environment such as the land use, drainage pattern, reconnaissance survey of the river, and a key interview to describe the barangay profile and the community's water use and practices. The water quality monitoring covers the evaluation of ten water quality parameters: temperature, pH, dissolved oxygen, total dissolved solids, total suspended solids, phosphate, nitrate, oil and grease, chloride, and E. coli.FINDINGS: Results of the study presents the water quality against the ten water quality criteria. Phosphate measured on four stations ranges between 2.40-4.50 mg/L exceeding the allowable 0.50mg/L; the oil and grease exceeds the standards 2 mg/L with measured values of 2.40-4.60 mg/L in stations 2, 3, and 4; while measured chloride in all stations prove that the water is salty with values exceeding the freshwater requirement of 250mg/L; and the measured TSS in stations 2, 3 and 4 ranges from 32.30 to 49.3 mg/L exceeds the standards of 30mg/L. E. coli was also detected in water samples collected in all sampling stations. The computed water quality index of 39.02 described water as poor, always impaired, and threatened by the surrounding environment. CONCLUSION: The measured concentrations for phosphate, oil/ grease, chloride, and TSS exceeds the water quality requirement suggesting that the water is contaminated. The E. coli detected in all water samples, further recommends prohibition of recreational activities to avoid accidental intakes and skin contact on the polluted water. The existing activities in the surrounding residential, commercial and agricultural areas contributed to water contamination as aggravated by the unreliable drainage system, absence of proper sanitation facilities, and collection and disposal behavior of the community. From this, a scientific basis can be drawn on how the river can be rehabilitated and protected and serve as guide for policymakers and water managers on implementing strategies to achieve sustainable water resources.
Environmental Engineering
J. Nesiba; R. Cuhlova
Abstract
BACKGROUND AND OBJECTIVES: This paper focuses on the development of Czech laws of water resource protection. The presented research examines the statistical data of the number and type of legislative acts concerning to water protection issued in the Czech Republic during the period 1990-2019. Several ...
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BACKGROUND AND OBJECTIVES: This paper focuses on the development of Czech laws of water resource protection. The presented research examines the statistical data of the number and type of legislative acts concerning to water protection issued in the Czech Republic during the period 1990-2019. Several types of legislative acts are followed in administrative law and statistically compared by the development in time and its type. The survey focuses on general water protection acts, water sewage management, agriculture sector, hygiene standards, and the protection of the basins of Czech rivers (e.g., blue water and gray water).METHODS: The analysis firstly concerns to the development of the number of legislative acts during 1990-2019 and secondly discusses a diversification of the legislative acts types (laws, decrees, resolutions, regulations, and strategic plans). A total of 12,272 legislative acts is analyzed during three phases of Czech modern history: 1990-1992 (Czechoslovakia), 1993-2003 (Czech Republic before its accession to the European Union), and 2004-2019 (Czech Republic in the European Union).FINDINGS: Statistical elaboration of legislative acts proves that it is possible to determine different types of water management over time. Protection of water resource management in the Czech Republic was forming from crisis management (1990-1992), via operational management (1993-2003) to strategic management (2004-2019). Current trends after 2020 show a new trend towards integral management.CONCLUSION: Findings provide better understanding of changeable importance of water protection and management attitudes in the Czech Republic in reaction to the development of society.