Network-Based Topological Exploration of the Impact of Pollution Sources on Surface Water Bodies

We developed a digital water management toolkit to evaluate the importance of the connections between water bodies and the impacts caused by pollution sources. By representing water bodies in a topological network, the relationship between point loads and basic water quality parameters is examined as a labelled network. The labels are defined based on the classification of the water bodies and pollution sources. The analysis of the topology of the network can provide information on how the possible paths of the surface water network influence the water quality. The extracted information can be used to develop a monitoring- and evidence-based decision support system. The methodological development is presented through the analysis of the physical-chemical parameters of all surface water bodies in Hungary, using the emissions of industrial plants and wastewater treatment plants. Changes in water quality are comprehensively assessed based on the water quality data recorded over the past 10 years. The results illustrate that the developed method can identify critical surface water bodies where the impact of local pollution sources is more significant. One hundred six critical water bodies have been identified, where special attention should be given to water quality improvement.

Longitudinal River Monitoring and Modelling Substantiate the Impact of Weirs on Nitrogen Dynamics

The fluvial nitrogen dynamics at locations around weirs are still rarely studied in detail. Eulerian data, often used by conventional river monitoring and modelling approaches, lags the spatial resolution for an unambiguous representation. With the aim to address this knowledge gap, the present study applies a coupled 1D hydrodynamic–water quality model to a 26.9 km stretch of an upland river. Tailored simulations were performed for river sections with water retention and free-flow conditions to quantify the weirs’ influences on nitrogen dynamics. The water quality data were sampled with Eulerian and Lagrangian strategies. Despite the limitations in terms of required spatial discretization and simulation time, refined model calibrations with high spatiotemporal resolution corroborated the high ammonification rates (0.015 d−1) on river sections without weirs and high nitrification rates (0.17 d−1 ammonium to nitrate, 0.78 d−1 nitrate to nitrite) on river sections with weirs. Additionally, using estimations of denitrification based on typical values for riverbed sediment as a reference, we could demonstrate that in our case study, weirs can improve denitrification substantially. The produced backwater lengths can induce a means of additional nitrogen removal of 0.2-ton d−1 (10.9%) during warm and low-flow periods.

Structure and Distribution of Macrobenthos Community in Code River, Yogyakarta, Indonesia

This research aimed to explore the community structure of macrobenthos in Code River, Yogyakarta. This research was conducted during December 2019-January 2020 in Code River, Yogyakarta. Data was taken 4 times in 6 stations. Macrobenthos was taken using a Surber net with a size of 30 x 30 cm and sampling at 5 spots in each station. Data analysis consisted of density, diversity index, dominance index, and evenness index. Water quality data consisted of water temperature, flow velocity, water depth, water pH, dissolved oxygen, and organic matter. The results showed that the density of macrobenthos ranged from 54-172 ind/m2. Our results showed that Code River has moderate diversity based on the Shannon-Wiener diversity index. Sulcospira testudinaria is the most dominant species in Code River. The evenness index showed high except at station 2 which was categorized as moderate. Code River has pretty good water quality, but stations 3, 4, and 5 which are located in the city area, it has a high organic matter content.

Determination of the Connectedness of Land Use, Land Cover Change to Water Quality Status of a Shallow Lake: A Case of Lake Kyoga Basin, Uganda

Catchments for aquatic ecosystems connect to the water quality of those waterbodies. Land use land cover change activities in the catchments, therefore, play a significant role in determining the water quality of the waterbodies. Research on the relationship between land use and land cover changes and water quality has gained global prominence. Therefore, this study aimed at determining land use, land cover changes in the catchments of L. Kyoga basin, and assessing their connectedness to the lake’s water quality. The GIS software was used to determine eight major land use and land cover changes for 2000, 2010, and 2020. Meanwhile, water quality data was obtained through both secondary and primary sources. Spearman correlation statistical tool in SPSS was used to correlate the land use, land cover changes, and water quality changes over the two-decade study period. The results showed that different land use and land cover activities strongly correlated with particular water quality parameters. For example, agriculture correlated strongly with nutrients like TP, TN, and nitrates and turbidity, TSS, BOD, and temp. The correlation with nitrates was statistically significant at 0.01 confidence limit. The findings of this study agreed with what other authors had found in different parts of the world. The results show that to manage the water quality of L. Kyoga, management of land use, land cover activities in the catchment should be prioritized. Therefore, the results are helpful to decision and policy makers and relevant stakeholders responsible for water management.

Impact of Water Quality Detorioration in Mangrove Forest in Semarang Coastal Area

The fast-growing development and industrialization have caused various impacts on nature including heavy metal pollution, especially in the coastal area. Tambakredjo, located in the North Semarang city, is home to a large number of mangrove and animal species. Therefore, water quality is important. This study was conducted to analyze water quality in the coastal area of Tambakredjo based on physical and chemical measurements. Water quality data were collected from different sites. Physical parameters (temperature, pH, DO, EC, TDS, ORP and salinity) and chemical parameters (Total N, Total P, Pb, Cr, Cd) were observed. Multivariate statistical techniques, including Principal Component Analysis (PCA), was applied to evaluate water quality. The results showed first principal component is 76.27%, where the highest conductivity, total dissolved solids and salinity are associated with site 1. Content of Lead 1.289 ppm, Cadmium 0.021 ppm, and Chromium 0.352 ppm exceeds the water quality standard PP. No. 82/2001. It indicated that Site 1 was characterized as the most heavily polluted site because the location received pollutants from rivers and oceans. This study also examined the short-term changes of the mangrove-covered area at the side of Banjir Kanal Timur using historical map satellite images. The results show that mangrove coverage in Tambakredjo near the aquaculture area had decreased from 1,875m2 to 1,401m2. Meanwhile, on the other site, the mangrove planting effort as a restoration program is carried out, especially in the estuary of Banjir Kanal Timur to anticipate more environmental changes.

Elemental Concentrations of Major and Trace Elements in the Spring Waters of the Arctic Region of Russia

The Arctic region of Russia is rich with natural water resources. Some residents of this area prefer to use water from spring sources instead of tap water. However, the elemental composition for most of the springs is unknown, making it very important to regularly update water quality data. In this paper, the chemical composition of 24 natural springs near large cities of the Murmansk region were identified via titration, potentiometry, and mass spectrometry analysis with the low detection limits. The concentrations of a considerable number of micro-components have been determined for the first time. Concentrations of some hazardous pollutants have been found in spring water that exceed Russian hygienic limits by 2.5 times. In terms of chemical indicators, it was shown that in accordance with European and national water standards, only half of the tested natural water sources in the Murmansk region can be used for drinking water. The preferential spring was recommended near each major city in the region according to a set of chemical parameters. The results of chemical composition of the spring waters were disseminated publicly by placing the tags with QR codes with the link to the cloud storage near each studied spring.

Assessment of Spatio-temporal Variations of Selected Water Quality Parameters of Lake Ziway, Ethiopia Using Multivariate Techniques

Lake Ziway is shallow freshwater located in Northern part of Ethiopian Rift Valley. It is characterized as semi-arid to sub-humid type of climate. Expansions of the flower industry, widespread fisheries, intensive agricultural activities, fast population growth lead to deterioration of water quality and depletion of aquatic biota. In this study, spatial and temporal variations of selected water quality parameters of Lake Ziway were evaluated using multivariate statistical techniques in the study periods of 2014 and 2015. Monthly water quality data were collected from nine sampling stations during dry and wet seasonal basis for analysis of 15 water quality parameters. Mean nutrient concentrations showed increasing trend and were higher in Floriculture effluent (Fb) and Floriculture effluent after mixing in the lake (Fa) in all seasons. These sites were also characterized by high electrical conductivity (EC) and total dissolved solid (TDS). All the nine sampling sites were categorized into three pollution levels according to their water quality features using cluster analysis (CA). Accordingly, sampling sites Fb and Ketar River (Kb) are highly and moderately polluted in both seasons, respectively. On the other hand, sampling sites at the center (C), Meki river mouth (Ma), Ketar river mouth (Ka), Meki River (Mb), Korekonch (Ko) and Fa in dry season and Ka, C, Ma, Ko, Bulbula river mouth (B) and Fa during wet season were less polluted. Principal component analysis (PCA) analysis also showed the pollutant sources were mainly from Fb during dry season Mb and Kb during wet season. The values of comprehensive pollution index illustrated the lake is moderately and slightly polluted in dry and wet seasons, respectively. Comparatively, the pollution status of the lake is high around floriculture effluent discharge site and at the two feeding rivers (Kb and Mb) due to increasing trends in agrochemical loads. This may lead to long term ecological changes in the lake unless possible measures taken.

Multivariate Analysis of Water Quality Measurements on the Danube River

This study investigates the potential of using principal component analysis and other multivariate analysis techniques to evaluate water quality data gathered from natural watercourses. With this goal in mind, a comprehensive water quality data set was used for the analysis, gathered on a reach of the Danube River in 2011. The considered measurements included physical, chemical, and biological parameters. The data were collected within seven data ranges (cross-sections) of the Danube River. Each cross-section had five verticals, each of which had five sampling points distributed over the water column. The gathered water quality data was then subjected to several multivariate analysis techniques. However, the most attention was attributed to the principal component analysis since it can provide an insight into possible grouping tendencies within verticals, cross-sections, or the entire considered reach. It has been concluded that there is no stratification in any of the analyzed water columns. However, there was an unambiguous clustering of sampling points with respect to their cross-sections. Even though one can attribute these phenomena to the unsteady flow in rivers, additional considerations suggest that the position of a cross-section can have a significant impact on the measured water quality parameters. Furthermore, the presented results indicate that these measurements, combined with several multivariate analysis methods, especially the principal component analysis, may be a promising approach for investigating the water quality tendencies of alluvial rivers.

An innovative subterranean spring capture method for improved water quality

Many rural communities in Andean countries of South America rely on springs as their primary drinking water source. A variety of spring capture methods are employed resulting in varying water quality. Water from these spring-fed sources, delivered to the community via a distribution network, is often not chlorinated, increasing the risk of water-borne pathogens. A simple, improved technique has been developed in Ecuador's Chimborazo Province by a local Christian organization, Corporación de Desarrollo Integral Socio Económico (CODEINSE), to protect spring water sources for community water supply. This new technique, ‘the CODEINSE method’, builds on the strengths of traditional subterranean spring captures while employing several design improvements, like a concrete cap and sufficient gravel pack, to prevent surface water contamination. According to water quality data collected in Ecuador, the CODEINSE method consistently provides high-quality water with substantially reduced levels of water-borne pathogens compared to traditional spring capture methods. On average, the CODEINSE method yields water with less than 1.0 CFU/100 mL, water that is deemed no risk by the World Health Organization. The CODEINSE method has the potential to improve water quality not only in the rural Andean communities in Ecuador but also in developing countries across the world.