Sediment and Water Quality of the Nile Delta Estuaries

Conversion of forested lands to agriculture or urban/residential areas has been associated with declines in stream and lake water quality. Less attention has been paid to the effects of adjacent land-uses on wetland sediment and water quality and, perhaps more importantly, the spatial scales at which these effects occur. Here we address these issues by examining variation in water and sediment nutrient levels in 73 southeastern Ontario, Canada, wetlands. We modeled the relationship between water and sediment nutrient concentrations and various measures of adjacent land-use such as forest cover and road density, measured over increasing distances from the wetland edge. We found that water nitrogen and phosphorous levels were negatively correlated with forest cover at 2250 meters from the wetland edge, while sediment phosphorous levels were negatively correlated with wetland size and forest cover at 4000 meters and positively correlated with the proportion of land within 4000 meters that is itself wetland. These results suggest that the effects of adjacent land-use on wetland sediment and water quality can extend over comparatively large distances. As such, effective wetland conservation will not be achieved merely through the creation of narrow buffer zones between wetlands and more intensive land-uses. Rather, sustaining high wetland water quality will require maintaining a heterogeneous regional landscape containing relatively large areas of natural forest and wetlands.

A drastic level of resource degradation was revealed through a preliminary evaluation (completed in 2016) of water quality in a recreational lake in the second industrial city in Dammam, Saudi Arabia. The primary signs were a foul smell, algal bloom, high turbidity, and lack of aquatic life. This study aims to evaluate the influence of reverse osmosis (RO) on lake water quality. The recreational lake consists of two connected lakes (Lakes 1 and 2), which receive treated effluent from an industrial wastewater treatment plant. Composite samples were collected from the lakes to analyze their physiochemical parameters. Descriptive analyses were performed, and two water quality indices were developed to observe the variations in water quality conditions between the two periods (2016 and 2021). The results indicated that the water parameters of total dissolved solids (TDS), sulphate (SO42−), biological oxygen demand (BOD), and dissolved oxygen (DO) in 2016 (3356, 4100, 516, and 1.32 mg/L, respectively) were significantly improved in 2021 (2502, 1.28, 9.39, and 7.79 mg/L, respectively). The results of the water quality index (WQI) and comprehensive pollution index (CPI) indicated that the water quality in Lake 1 was significantly enhanced in 2021 (WQI = 85, CPI = 1) in comparison with assessment data from 2016 (WQI = 962, CPI = 8). However, the data from Lake 2 revealed higher pollution levels in 2021 (WQI = 1722, CPI = 18) than those recorded in 2016 (WQI = 1508, CPI = 13). As indicated by the absence of bad smells, algal blooms, and restoration of aquatic life, the RO intervention successfully improved the water quality in Lake 1. The WQI and CPI were helpful tools for evaluating lake water quality.

In Ghana, small-scale mining (SSM) has been carried out for many years, generating employment and income. Currently, illegal artisanal mining (‘galamsey’) has impacted the environment negatively, resulting in land degradation and water pollution. The government of Ghana, responding to public outcry against the negative effects of ‘galamsey’, placed a ban on illegal small-scale mining activities in March 2017. This ban stopped both ‘legal’ small-scale and the illegal artisanal miners from carrying out any such activity. In July 2018, this study was carried out to examine the status of water and sediment quality in eight endemic regions of illegal mining to ascertain the outcome of the ban on the water quality of the rivers. Methodologies in the Standard Methods for the Examination of Water and Wastewater were followed. Results of the study indicated that the rivers were high in total suspended solids (TSS), turbidity and colour, suggesting inflow of wastewater from the illegal mining activities and some run-off. Colour had a strong correlation with turbidity (r = 0.95) and TSS (r = 0.94), suggesting that the pollution originates from the same sources. Low levels of metals were found in both water and sediment. However, very high concentrations of Fe were detected in both water and sediment. Mercury concentrations were low in the water column but relatively higher in the sediment. A comparison of the general water quality status of the water bodies in the Pra Basin in 2013 and 2018 using the Water Quality Index (WQI) showed a marginal improvement in quality in 2018 over 2013 in the Pra Basin. The improvement of water quality in 2018 is attributable to the ban.

Coal mine generated open pit lakes are well distributed in Raniganj coal field area, West Bengal, India. This paper screened out ecological state macrophyte index (ESMI), water quality index (WQI) and multivariate statistical methods to assess the ecological status of four pit lakes, Nagrakonda, Joyalbhanga, Dalurbandh, and Kumardihi. Seven water quality parameters (pH, total dissolved solids, dissolved oxygen, Secchi depth nitrate, chloride, and phosphate) and six sediment quality parameters (pH, organic carbon, bulk density, particle density, available nitrogen and phosphorus) were analyzed for one year on a monthly basis from four pit lakes. The abundance and diversity of aquatic macrophytes were also analyzed. In the studied pit lakes, water and sediment quality variables showed significant spatial variation. WQI showed that the water quality in all pit lakes was good and according to ESMI these lakes were categorized into good ecological status. The results of this study indicated the values of water quality and macrophyte based indices highlighted the ecological condition of the pit lakes of the study sites thus should be considered it as reliable tool for assessing of the ecological status of any wetlands.

Multivariate statistical analyses for water and sediment quality index development: A study of susceptibility in an urban river

Increasing population growth, economic and industrial development will lead to the utilization of natural resources effected on water pollution. One of those activities related to natural resource utilization is gold mining. Mining activities cannot be separated from the use of chemicals that are harmful to living things; for example, it is mercury. This study aims to determine levels of mercury (Hg) that accumulate in water and sediments. The tools used in this research are QGIS 2.18.27 software and Global Positioning System. The material used is water and sediment samples. Water and sediment samples were analyzed at the Industrial Standardization Research Institute Laboratory to obtain several potential parameters such as hydrogen (pH), mercury (Hg), Lead (Pb), Iron (Fe), and Copper (Cu). These potential parameters are further analyzed using the Pollution Index (PI) method and Sediment Quality Guidelines (SQGs). The results demonstrated that the water quality in downstream of Krueng Kluet sub-watershed in for 2019 using the Pollution Index (PI) method for the drinking water (Class I) with the value is 6.2036. It is classified as moderately polluted water quality criteria and for the agricultural water (Class IV) with the value is 6.0796, classified as moderately polluted water quality criteria. The quality of sediments in the downstream of Krueng Kluet sub-watershed using the sediment quality guidelines method with the value is 0.2343 is classified as an adverse effect for the biota of heavy metals on medium value. This shows that neither the water quality nor the sediment in the downstream of Krueng Kluet sub-watershed does not accord with the water and sediment quality standards. Pollution Index can assess the quality of water bodies and becomes a consideration in taking actions to improve water quality. At the same time, SQGs show chemical concentrations that have biological effects on aquatic biodata.

To Lich River (TLR) system receives wastewaters from a population of nearly two million people and 99 manufacturers of five industrial zones in inner city Hanoi, Vietnam.To improve quality of TLR, the construction of an embankment has been carried out during the period 1998-2002.Water and sediment quality indices based on heavy metal concentrations were used to evaluate the current river environment compared to that of the pre-embankment.The mass balance model was employed to estimate total metal loads for specific river reaches, which correspond to various types of wastewater discharged along the river.The results indicated that domestic-discharged river reaches received much lower metal loads, roughly 8-28% compared to river reaches of both domestic and industrial inputs.Total load of all nine concerned metals (Cr, Mn, Fe, Ni Cu, Zn, As, Cd, and Pb) at the end of TLR is 161.7 kg/day.Water quality was improved after completion of the embankment, then it gradually deteriorated.Meanwhile, sediment quality became much worse after the embankment.Relative river quality index as an equal weight for both water and sediment quality indices indicated that quality of TLR was not much improved after the embankment.It even became worse due to urbanization in recent years.To improve quality of a sewage system, the embankment is not enough and is just an initial stage.The next stage which may become more important is a treatment plan to fully treat wastewater at sources following environmental standards before discharging to a sewage system.

Fundão dam (Minas Gerais, Brazil) breached on 5 November 2015, releasing 50 million m³ of Fe ore tailings and dam materials into the upper Doce River system. The tailings travelled 670 km along the river system to the ocean. Starting on 17 November 2015, 6 days before the tailings reached the Doce River mouth, a water quality monitoring program with a daily sampling schedule was implemented by Samarco Mineração S.A. (Samarco) to assess the impacts on marine water and sediment quality. Between November 2015 and August 2017 water and sediment quality were monitored at 28 locations offshore from the Doce River mouth. The sampling areas were grouped by hydrological and metocean season (i.e., rainy and dry seasons and wave and wind climates), distance from the river mouth (<5 km, >5 km and within a Marine Protected Area), and water depth. The data were compared to the Brazilian water quality standards and prebreach conditions. Statistical tests were conducted to evaluate temporal and spatial trends and patterns. For the water quality parameters of relevance (total suspended solids, turbidity, total and dissolved Fe, Al, and Mn), pulses of concentration increases were observed right after the arrival of the plume in the coastal zone and during the subsequent rainy seasons. Exceedances of prebreach conditions were more frequent closer to the Doce River mouth. During the dry season, concentrations tended to decrease, reaching prebreach levels for a number of parameters, with small short-term pulses associated with metocean factors. For sediment quality parameters of relevance (particle size, Fe, Al, and Mn), Fe was the only one that clearly resulted from the dam breach, which was mediated by river influence and oceanographic factors affecting particle size distribution. Results indicated that the Fundão dam failure did affect water and sediment quality in the Atlantic Ocean, with greater impacts closer to the river mouth and immediately after the arrival of the tailings plume, with concentrations gradually returning to preevent levels over time. Integr Environ Assess Manag 2020;16:643-654. © 2020 SETAC.

In this work, a hydrodynamic and water quality model was developed for Lake Nubia based on a two-dimensional, laterally averaged and finite difference hydrodynamic and water quality code, CE-QUAL-W2. The model was calibrated and verified using data which were measured in the years of 2006 and 2007 during low flood periods, respectively. Measurements during the flood season are not available. The results of the presented model show a good agreement with the observed hydrodynamic and water quality records.&#13;\nTwo water quality indices (WQIs), NSF WQI and CCME WQI, have been developed to assess the state of water quality in the investigated case study, Lake Nubia, during the first low flood period of January 2006. The CCME WQI has been modified to use the Egyptian standards (objectives) of raw water. Moreover, another two trophic status indices, Carlson TSI and LAWA TI, have been developed to evaluate the trophic status of Lake Nubia during the same period of January 2006. Results of the previously developed hydrodynamic and water quality model for Lake Nubia were used to validate the model. According to the developed water quality indices results, Lake Nubia has a good water quality state during the low flood period. The modified CCME WQI (based on measured data) indicates that the Lake Nubia water quality state is excellent according to the Egyptian standards of water quality for surface waterways. Results of the applied trophic status indices show that the Lake Nubia trophic status is eutrophic during the studied period. &#13;\nThe effect of the global climate change on the hydrodynamic and water quality characteristics of Lake Nubia was conducted for the 21st century. To do that, the outputs of eleven global climate models for two global emissions scenarios combined with hydrological modeling were used. A theoretical process algorithm has been simplified, further developed and calibrated to modify the initial conditions of dissolved oxygen due to the global climate change effects. A sensitivity analysis has been conducted by using each of the predicted air temperature and inflow data separately in the model in order to investigate its effect on the characteristics of the hydrodynamic and water quality. Three hydrodynamic characteristics of the reservoir were investigated with respect to the climate change: water surface levels, evaporation water losses and thermal structure. In addition, eight water quality characteristics of the reservoir were investigated with respect to the climate change: dissolved oxygen, chlorophyll-a, ortho-phosphate, nitrate-nitrite, ammonium, total dissolved solids, total suspended solids and potential of hydrogen (pH). Moreover, the climate change effects on the water quality and trophic status indices have been studied. The results of the climate change study show partially significant impacts on the examined hydrodynamic and water quality characteristics, while the water quality and trophic status indices are slightly affected by the climate change scenarios.

Emet River Basin is a worldwide significant mining area and contains the most important boron and chromium deposits of Turkey. In this study, water and sediment quality of Emet River Basin was evaluated using some toxic element risk assessment indices. Samples were collected seasonally from 8 locations and nickel (Ni), chromium (Cr), arsenic (As), zinc (Zn), lead (Pb), copper (Cu) and cadmium (Cd) accumulations in water and sediment were analysed using an ICP-OES. Water Quality Index (WQI), Heavy Metal Pollution Index (HPI), Heavy Metal Evaluation Index (HEI) and Degree of Contamination Index (Cdeg) were applied to the data for assessing the water quality and Biological Risk Index (BRI), Potential Ecological Risk Index (PERI), Geo-Accumulation Index (Igeo), Contamination Factor (CF) and Pollution Load Index (PLI) were applied to the data for assessing the sediment quality. According to the results of WQI, HPI, HEI and Cdeg, As and Cr were recorded as the most dangerous toxicants; according to the results of BRI, Igeo, CF and PLI, Cd, As and Pb were recorded as the most dangerous toxicants; and according to the results of PERI, Ni and Cr were recorded as the most dangerous toxicants among the investigated elements. The seasonal average values of applied ecological indices for the water of the basin ranged 71.41–888.29 for WQI, 85.97–915.76 for HPI, 4.04–49.80 for HEI and − 2.95–42.80 for Cdeg. The seasonal average values of applied ecological indices for the sediment of the basin ranged 33.72–130.56 for PERI, 0.14–0.93 for BRI, − 3.92–5.99 for Igeo and 0.45–1.20 for PLI. In addition to the intensive agricultural applications around the region, the geological structure of the watershed was considered as the main cause of the high heavy metal accumulations in basin waters and sediments.

Water quality assessment and pollution evaluation of surface water sources: The case of Weishan and Luoma Lakes, Xuzhou, Jiangsu Province, China

River and lake basins can be regarded as primary water sources, providing communities with a variety of services, including food supplies, flora and fauna habitats, and household uses. To evaluate the state of the water quality, particularly in the lake basin, sedimentation issues and water quality status are considered. The Kenyir Lake Basin's health was tracked in this study using the Water Quality Index (WQI), JPS River Index (JRI), and Sediment Load (SL) production. Determining and analysing the trends in water quantity and quality throughout the Kenyir Lake Basin was the goal of this study. For the purpose of this study, samples were taken at 21 different locations around the lake basin in the wet (November), dry (September), and normal (July) seasons. Six WQI parameters, four JRI parameters, and three SL production parameters have been chosen. In the linear connection to forecast WQI, JRI, and SL, several important variables serve as inputs. The key parameters were identified for each index, such as pH, Dissolved Oxygen (DO), and ammoniacal nitrogen (NH₃-N) which were critical for the WQI; specific flow was essential for the JRI; and Total Suspended Solids (TSS) were important for the sediment load (SL) production analysis. Furthermore, the Hazard Quotient (HQ) was subsequently calculated to conduct a preliminary assessment of the potential health risks associated with metal exposure. The elements' HQ ingestion values were discovered to be in the following order: Arsenic (As) &gt; Cadmium (Cd) &gt; Copper (Cu) &gt; Cobalt (Co) &gt; Chromium (Cr) &gt; Nickel (Ni) &gt; Zinc (Zn) &gt; Plumbum (Pb); all averaged HQ values were less than 1, suggesting that there was little to no health risk from the metals in question. Overall, the WQI results indicate that the basin's water quality is generally Class I to Class II, with WQI values of at least 60% across all sampling points. Linear relationship analysis identified DO as the most critical parameter influencing the WQI across all seasons (contributing up to 64.40% in the dry season), followed by ammoniacal nitrate (AN) and Biochemical Oxygen Demand (BOD). The human health risk assessment revealed that the non-carcinogenic risk from metal exposure (As, Cd, Cu, Co, Cr, Ni, Zn, Pb) was negligible, as all averaged HQ values were less than 1. However, the carcinogenic risks associated with exposure to As and Cr were identified as high. Although the water quality has not reached a critical threshold, unregulated anthropogenic activities pose a substantial and intensifying threat to the ecosystem and local communities. These findings necessitate a more systematic environmental management approach to mitigate future degradation. Apart from the river, anthropogenic activities such as sand mining, tourism, agriculture, and municipal wastewater treatment were assessed using secondary data obtained from land use records, environmental monitoring reports, and official discharge statistics. Analysis of these data revealed that such activities play a substantial role in contributing to the concentration of polluting elements in the river water. Although the current level of water quality and quantity degradation in the Kenyir Lake Basin has not yet reached a critical threshold, the potential adverse impacts on the ecosystem and local communities are likely to intensify if these anthropogenic pressures remain unregulated.

As a part of the monitoring practice of the lone natural habitat of the endemic and endangered Rucervus eldii eldii McClelland or Sangai, the paper reports sediment and water characteristics of Keibul Lamjao National Park-the only floating national park of the world in Manipur, Indo Burma hotspot. The water analysis showed low pH (5.69 ± 0.16), high electrical conductivity (342 ± 13.01 μS m-1), high turbidity (33.2 ± 9.407 NTU), and high phosphate concentrations (0.92 ± 0.11mg L-1) during the study period. The water quality index values calculated indicate that the park water during post-monsoon season is unfit for drinking. Thus, the degrading water quality poses a serious risk to the health of the deer and other species in the park. At present, Sangai in its natural habitat is threatened by pollution, encroachment, phoomdi thickness reduction, and inbreeding depression. To address the problem of inbreeding, Pumlen pat is considered as a second suitable natural habitat for the deer reintroduction program. During the study, water characteristics of the wetland showed similar characteristics as KLNP, i.e., low pH (5.86 ± 0.30), high electrical conductivity (377.6 ± 5.55 μS m-1), high turbidity (32.36 ± 4.91 NTU), and high phosphate concentrations (0.79 ± 0.14mg L-1). Likewise, sediments showed high TP accumulation that ranged from 197.03 ± 0.75 to 332.88 ± 0.99mgkg-1 for KLNP and 245.18 ± 0.85 to 351.48 ± 0.71mgkg-1 for Pumlen pat, respectively. Both, the lone natural habitat and the proposed habitat showed deteriorating water quality. As such, continuous monitoring of KLNP and Pumlen pat water and sediment quality should be a priority during the management practices to protect the endangered deer and health of the habitats for long-term conservation.

Environmental quality assessment in a marine coastal area impacted by mining tailing using a geochemical multi-index and physical approach

Site selection for shellfish aquaculture by means of GIS and farm-scale models, with an emphasis on data-poor environments