Water quality studies in Kranji catchment, Singapore: use of organic tracers and polyethylene devices for identifying potential sewage sources

2012 ◽  
Vol 7 (2) ◽  
Author(s):  
A. R. Mendez Sagel ◽  
P. Shanahan ◽  
J. K. MacFarlane ◽  
P. M. Gschwend
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Endocrine Disruptors ◽  
Passive Samplers ◽  
Nonylphenol Ethoxylates ◽  
Residential Areas ◽  
Future Studies ◽  
Rivers And Streams ◽  
Laboratory Results ◽  
Polyethylene Devices

The objective of this study was to identify organic compounds that could serve as indicators of potential human fecal contamination sources to the Kranji Reservoir in Singapore and could be used as confirmation indicators along with bacteria indicators. The compounds chosen as potential tracers were nonylphenol (NP) and nonylphenol ethoxylates (NPEs), as these are indicative of sewage and have been found at measurable concentrations in rivers and streams elsewhere in Asia. Polyethylene devices (PEDs) were used as passive samplers to measure NP and NPEs in stormwater drains in Kranji Catchment, deployed in areas of different land use in order to obtain an overview of concentration ranges across the catchment and provide an indication of where and why these compounds could be found. Laboratory results showed that NP and NPEs were present in non-residential areas and preliminary modeling of corresponding water concentrations indicates potentially risky concentrations of NP in the water in some stormwater drains. More information is needed on detergents in Singapore to further evaluate using NPEs as sewage indicators. Future studies should be done to confirm concentrations in Kranji Catchment water to verify if there is a risk to the ecosystem's health as NP and NPEs are known endocrine disruptors.

Relationship between land use and water quality in a small watershed in South Korea

2010 ◽  
Vol 62 (11) ◽  
pp. 2607-2615 ◽  
Author(s):  
J. Y. Lee ◽  
J. S. Yang ◽  
D. K. Kim ◽  
M. Y. Han
Keyword(s):  
Water Quality ◽  
Land Use ◽  
River Water ◽  
Agricultural Land ◽  
Principal Component ◽  
Quality Parameters ◽  
River Water Quality ◽  
Water Quality Parameters ◽  
Metallic Ions ◽  
Residential Areas

Recent research and monitoring undertaken by various institutions have emphasized measurements of river-water quality. Based on the results, government agencies have set guidelines to improve river-water quality management. However, the relationship between water quality and land use/land cover (LULC) has not been examined closely in South Korea to date. This study investigated this relationship in the Imgok River watershed. For this study, the relationship between water quality parameters, e.g. metallic ions, biological oxygen demand and chemical oxygen demand (BOD and COD), NH3, NO3 and PO4 levels and land-use types (abandoned mine land, forest/grassland, agricultural, livestock and residential areas) was examined by correlation analysis with significant level (p < 0.05) and principal component analysis (PCA). Applying PCA to water quality parameters according to land-use coverage, the principal component impacting river water quality were found to be the pH, metallic ions, BOD, PO4, COD and total suspended solids (TSS) for abandoned mine land (AML) coverage; BOD, NO3 and PO4 for forest/grassland areas; TSS, NO3, and PO4 for agricultural land; BOD, COD, NH3 and NO3 for livestock coverage; and BOD, COD, NH3 and PO4 for residential areas. For the AML, the pH exhibited a significant negative correlation with other water quality parameters at the significant level (p < 0.05). Grassland showed significant positive correlations of BOD with values of 0.837 NO3 and 0.514 PO4. In agricultural land, TSS had a significant negative correlation with value of −0.772 PO4. For livestock coverage, BOD had significant positive correlations with values of 0.865 COD, 0.629 NH3, 0.709 NO3 and 0.472 TSS. In residential areas, COD was significantly positively correlated with values of 0.988 BOD and 0.856 PO4, and TSS was highly positively correlated with value of 0.810 NO3 but highly negatively correlated with value of −0.702 PO4. Based on the above, LULC is a significant factor to influence on river water quality and this relationship should be based on the management plan for river water quality control. Future work will be conducted to take more samples in the entire river and season, to run water quality model and to choose a new method for better analysis and more accurate relationship between land-use and water quality.

Monitoring land use change in the Lake Taupo catchment between 1975, 1990 and 2002 using satellite remote sensing data

2007 ◽  
pp. 17-22
Author(s):  
H. Lilienthal ◽  
A. Brauer ◽  
K. Betteridge ◽  
E. Schnug
Keyword(s):  
Remote Sensing ◽  
Water Quality ◽  
Land Use ◽  
Land Use Change ◽  
Satellite Remote Sensing ◽  
Remote Sensing Data ◽  
Native Vegetation ◽  
Lake Water Quality ◽  
Livestock Farming ◽  
Slow Decline

Conversion of native vegetation into farmed grassland in the Lake Taupo catchment commenced in the late 1950s. The lake's iconic value is being threatened by the slow decline in lake water quality that has become apparent since the 1970s. Keywords: satellite remote sensing, nitrate leaching, land use change, livestock farming, land management

Pesticide Contamination of Groundwater in Virginia: BMP Impact Assessment

1993 ◽  
Vol 28 (3-5) ◽  
pp. 379-387 ◽  
Author(s):  
S. Mostaghimi ◽  
P. W. McClellan ◽  
R. A. Cooke
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Best Management Practices ◽  
Water Samples ◽  
Management Practices ◽  
Water Quality Monitoring ◽  
Pesticide Contamination ◽  
Cropping Patterns ◽  
Creek Watershed ◽  
Surface And Groundwater

The Nomini Creek Watershed/Water Quality monitoring project was initiated in 1985, as part of the Chesapeake Bay Agreement of 1983, to quantify the impacts of agricultural best management practices (BMPs) on improving water quality. The watershed monitoring system was designed to provide a comprehensive assessment of the quality of surface and groundwater as influenced by changes in land use, agronomic, and cultural practices in the watershed over the duration of the project. The primary chemical characteristics monitored include both soluble and sediment-bound nutrients and pesticides in surface and groundwater. Water samples from 8 monitoring wells located in agricultural areas in the watershed were analyzed for 22 pesticides. A total of 20 pesticides have been detected in water samples collected. Atrazine is the most frequently detected pesticide. Detected concentrations of atrazine ranged from 0.03 - 25.56 ppb and occurred in about 26 percent of the samples. Other pesticides were detected at frequencies ranging from 1.6 to 14.2 percent of all samples collected and concentrations between 0.01 and 41.89 ppb. The observed concentrations and spatial distributions of pesticide contamination of groundwater are compared to land use and cropping patterns. Results indicate that BMPs are quite effective in reducing pesticide concentrations in groundwater.

scholarly journals Spatial-Temporal Change of Land Use and Its Impact on Water Quality of East-Liao River Basin from 2000 to 2020

Water ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1955
Author(s):  
Mingxi Zhang ◽  
Guangzhi Rong ◽  
Aru Han ◽  
Dao Riao ◽  
Xingpeng Liu ◽  
...  
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Land Use Change ◽  
Point Source ◽  
Water Body ◽  
Forest Land ◽  
Point Source Pollution ◽  
Construction Land ◽  
Unused Land ◽  
Non Point Source Pollution

Land use change is an important driving force factor affecting the river water environment and directly affecting water quality. To analyze the impact of land use change on water quality change, this study first analyzed the land use change index of the study area. Then, the study area was divided into three subzones based on surface runoff. The relationship between the characteristics of land use change and the water quality grade was obtained by grey correlation analysis. The results showed that the land use types changed significantly in the study area since 2000, and water body and forest land were the two land types with the most significant changes. The transfer rate is cultivated field > forest land > construction land > grassland > unused land > water body. The entropy value of land use information is represented as Area I > Area III > Area II. The shift range of gravity center is forest land > grassland > water body > unused land > construction land > cultivated field. There is a strong correlation between land use change index and water quality, which can be improved and managed by changing the land use type. It is necessary to establish ecological protection areas or functional areas in Area I, artificial lawns or plantations shall be built in the river around the water body to intercept pollutants from non-point source pollution in Area II, and scientific and rational farming in the lower reaches of rivers can reduce non-point source pollution caused by farming.

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