Improve Water Quality Research Articles

The dominant mechanisms of nutrient cycling in high-dam reservoirs: retention, transport or transformation?

Abstract High-dam reservoirs can significantly affect nutrient cycling processes across the globe. However, the research community now has two contradictive views (i.e. retention versus transformation) about the impact of high-dam reservoirs on nutrient cycling due to incomplete information obtained from limited field samplings. To resolve this issue, we develop a physically-based, three-dimensional water quality model to examine the spatiotemporal distributions of biogenic elements (nitrogen and phosphorus) in high-dam reservoirs with high spatial and temporal details. We apply the model to the Xiaowan Reservoir, a representative high-dam reservoir in the Lancang River Basin. By scrutinizing the spatiotemporal distributions of biogenic elements across space and over time, we find a unique ‘retention-transformation-transportation’ process of nitrogen and phosphorus in the high-dam reservoir, with dominant transformation occurring in the water zone before the dam during non-flood period while dominant retention occurring in the middle part of a reservoir during flood period. We further find that transformations of biogenic elements are enhanced only in low-temperature and low-oxygen environments. Our findings show solid scientific basis to resolve the contradictive views about nutrient cycling mechanisms in high-dam reservoirs, and provide important policy implications for the operation of high-dam reservoirs to achieve improved water quality while maintaining clean energy supply.

Standardization of FTIR-Based Methodologies for Microplastics Detection in Drinking Water: A Meta-Analysis Indeed and Practical Approach

The detection of microplastics (MPs) in drinking water presents significant environmental and public health challenges. This study comprises two stages: a meta-analysis aimed at standardizing Fourier Transform Infrared Spectroscopy (FTIR) methods for MP detection, followed by the practical implementation of these findings in the laboratory. The review of studies conducted from 2019 to 2023 identifies 0.45 μm cellulose nitrate filters and Nile red staining as the most effective techniques for fluorescent detection. Experimental results demonstrate the superior retention capabilities of cellulose nitrate filters and the uniformity of Nile red staining. This dual approach not only optimizes water treatment processes but also enhances the accuracy of MP detection. The findings contribute to improved water quality management and public health protection by establishing robust protocols for MP analysis.

Willingness to Pay for Improved Groundwater due to BMPs in PEI.

This study uses stated preference techniques to evaluate the willingness to pay for improved groundwater in PEI, which allows us to estimate the social cost of nitrogen in this region. 'Beneficial Management Practices' (BMPs) are often employed in PEI's agricultural sector, to improve crop yields but also reduce adverse environmental effects such as nitrogen leaching that can affect ground and surface waters. PEI residents were surveyed to estimate a dollar value of improved water quality due to reduced nitrogen leaching due to BMPs. From the responses to a double-bounded dichotomous choice survey, models using maximum likelihood estimation showed that residents of PEI were willing to pay roughly $230 per year to see a reduction in nitrogen of either 20% or 50%, which translated to $5-13 per kg of nitrogen reduced. However, excluding 'yeah-sayers' and protest votes suggests that WTP is lower for the 20% reduction and increases as nitrogen reduction increases. Thus, a social cost of $13/kg should be considered an upper bound in PEI. WTP values, as well as estimates of the social cost of nitrogen are similar to values in previous literature. We find that variables such as cell phone usage, belief that farmers should pay for BMPs, and spending on water filtration have a statistically significant impact on WTP. Other variables are significant in some model specifications, however many demographic variables such as employment status and education do not affect WTP.

Evaluating the potability of domestic water supply sources using water quality index in Kilombero district, Tanzania

ABSTRACT The decline in water quality in various bodies of water has led to significant health risks for individuals relying on these sources for drinking and domestic use. The prevalence of waterborne diseases in some areas is attributed by inadequate water quality assessments of supply sources. This study focused on evaluating the potability of domestic water sources in the Kilombero district of Tanzania, where approximately 70% of the population depends on untreated natural sources. Two models were utilized: the Weighted Arithmetic Water Quality Index (WAWQI) and the Canadian Council of Ministers of Environment Water Quality Index (CCME WQI), analysing 15 water quality parameters. The WAWQI identified three groundwater sources as poor quality for consumption, while indicating seasonal improvements in water quality – from 12 in the wet season to 13 in the dry season. Conversely, the CCME WQI classified all 15 sources as potable, with an increase in ‘Excellent’ ratings from 9 to 13 between seasons. The findings showed that all surface water sources were deemed potable, while 67% of groundwater sources met quality standards. The remaining 33% of boreholes were categorized as having poor quality. Overall, both models indicated better water quality during the dry season, with surface water generally exhibiting higher quality than groundwater.

A Review on Storage Process Models for Improving Water Quality Modeling in Rivers

Water quality is intricately linked to the global water crisis since the availability of safe, clean water is essential for sustaining life and ensuring the well-being of communities worldwide. Pollutants such as industrial chemicals, agricultural runoff, and untreated sewage frequently enter rivers via surface runoff or direct discharges. This study provides an overview of the key mechanisms governing contaminant transport in rivers, with special attention to storage and hyporheic processes. The storage process conceptualizes a ubiquitous reactive boundary between the main channel (mobile zone) and its surrounding slower-flow areas (immobile zone). Research from the last five decades demonstrates the crucial role of storage and hyporheic zones in influencing solute residence time, nutrient cycling, and pollutant degradation. A review of solute transport models highlights significant advancements, including models like the transient storage model (TSM) and multirate mass transport (MRMT) model, which effectively capture complex storage zone dynamics and residence time distributions. However, more widely used models like the classical advection–dispersion equation (ADE) cannot hyporheic exchange, limiting their application in environments with significant storage contributions. Despite these advancements, challenges remain in accurately quantifying the relative contributions of storage zones to solute transport and degradation, especially in smaller streams dominated by hyporheic exchange. Future research should integrate detailed field observations with advanced numerical models to address these gaps and improve water quality predictions across diverse river systems.

Surface water quality in Costa Rica: new initiatives and challenges

ABSTRACT Despite Costa Rica's reputation for being a leader in environmental policy and its thriving nature-based tourism industry, the nation has had poor surface water quality. Reasons for poor water quality include the lack of sewerage treatment, overuse of septic tanks, and the application of large quantities of agrichemicals. Although Costa Rica has policies to maintain surface water quality, they have not been sufficiently implemented. Recent initiatives have addressed surface water quality, including an ambitious plan to expand treated sewerage systems in all urban areas. Current efforts to meet this goal have focused on the San Jose metropolitan area and coastal communities. This paper reviews the advances and challenges to Costa Rica's efforts to improve water quality.

Landfill leachate treatment process is transforming and releasing banned per- and polyfluoroalkyl substances to UK water

Landfills are a known source of PFAS pollution. Many have environmental permits allowing the discharge of treated leachate to controlled waters. In this article we compared leachate data for 17 PFAS from 17 different landfill sites across the UK. The results show that the landfill leachate treatment process (designed to improve water quality) is generating the banned PFAS; PFOA and PFOS. Approximately 80% of locations tested showed an increase in PFOS, with an increase of 1,335% in one sample. The highest concentrations of PFOS and PFOA in treated leachate were 2,460 ng L−1 and 26,900 ng L−1, respectively. When compared against the environmental quality standard of 0.65 ng L−1 for PFOS this leachate could pose a significant concern. Landfill leachate treatment has proven effective for a wide range of different pollutants, but this research shows in several instances that it is not appropriate for PFAS remediation.

Macrophytes Used as Multifaceted Benefits Including Feeding, Bioremediation, and Symbiosis in Freshwater Aquaculture—A Review

ABSTRACTThe utility of macrophytes in freshwater aquaculture is diverse. We review the benefits of macrophytes in aquaculture into broadly three useful perspectives: (i) Feeding, (ii) Bioremediation, and (iii) Symbiosis. Macrophytes are used as direct food by herbivores for their potential nutrient values with a maximal protein content of 35% (D/W basis) and as ingredients for fish feed preparation with optimal 50% protein inclusion to reduce feed cost in commercial aquaculture. Macrophytes are used for wastewater treatments to eliminate contaminants, including As, Cu, Cd, Cr, Hg, and Pb, to 99.9%, and to reduce BOD (Biological Oxygen Demand) to improve water quality. Intake of remedied wastewater into aquaculture enhances water productivity through phytoplankton growth. An estimate is that 1.0 L of remedied wastewater, particularly sewage effluent adds an average of 0.05 g N & P and 0.99‐L freshwater into aquaculture to yield an average of 0.309 g fish. Macrophytes are integrated with fish in commercial aqua‐farming. Plants and fish are farmed together in aquaponics. They are used as substrates for some commercial fish species to lay eggs in farming. They are raised with ornamental fish for benefits in aquariums. Nevertheless, extensive studies are required to harness more benefits from macrophytes.

Assessment of the water quality pollution index and ecological risk of microplastic pollution along the Tambakoso River in Surabaya, Indonesia

Increasing human activities and improper waste disposal will cause microplastic pollution in surface water. This study analyzed the abundance and characteristics of microplastics, pollution index based on water quality and its relationship with microplastic pollution, and the potential ecological risk of microplastics along the Tambakoso River which is influenced by various land uses of housing, industry, agriculture, and ponds from 16 sampling points. The average abundance of microplastics in the river was 91.80 particles/L. The Kruskal Wallis test showed that there were significant differences between microplastic pollution at each sampling location (Pvalue <0.05). In general, microplastics were mostly found in the form of fragments (48.36 %), transparent color (73.81 %), SMP size (<1 mm) (81.6 %), and dominated by PVC and nylon polymers. However, the characteristics of microplastics at each sampling location varied. The water quality pollution index value showed a slightly polluted category at most points. Redundancy analysis (RDA) showed that the characteristics of the shape and color of microplastics correlated with water quality parameters. The potential ecological risk based on microplastic pollution showed minor, moderate, and high categories at points with industrial land use. This indicates that the distribution of microplastics is closely related to human activities in the area. The level of ecological risk from microplastics depends on the percentage of each plastic polymer, along with its abundance in the environment. This study offers an important basis for designing efficient countermeasures to reduce microplastic pollution and improve water quality in surface waters.

A novel chitosan/biochar-modified eco-concrete with balanced mechanical, planting, and water purification performance for riparian restoration

The blocking between terrestrial and riverine ecosystems by impermeable concrete can cause negative impacts on plant growth, water quality, and biodiversity in riparian zones. Herein, pursuing a balance among mechanical, planting, and water purification property, chitosan/biochar-modified eco-concrete (CBEC) was prepared as a new sustainable alternative for riparian protection, ecological restoration and water quality improvement. Compressive strength of CBEC with an optimized chitosan/biochar content of 6% could reach up to 14.05 MPa, meeting the requirements for stabilizing riparian slopes. Micromorphology characterization and porosity measurement (29.63%) confirmed the abundantly porous structure of CBEC, facilitating the soil-water nutrient exchange, plant growth and microbial attachment. The 30-d water tank cultivation observed that the physiological parameters of T. orientalis planted in CBEC, including biomass, chlorophyll, protein and starch, were greatly improved compared to unmodified eco-concrete (EC). Moreover, compared to EC, biochar-modified EC and chitosan-modified EC, the planting CBEC could most effectively decrease the levels of TN, NH4+-N, TP, and COD by 53.82%, 62.50%, 88.31%, and 57.95%, respectively. Specially, the planting CBEC could degrade a common but recalcitrant pesticide nitenpyram (NTP) by 32.83% into low-toxic substances, recognized by LC-MS analysis. Microbiological analysis revealed that CBEC greatly promoted the proliferation of both nutrient-transforming bacteria (e.g., Nitrospira and Pseudomonas) and some specific species dominating NTP degradation (e.g., Rhodococcus and Bacillus). Also, PICRUSt2 prediction results identified the enrichment of functional genes related to nitrogen and phosphorus transformation. Our findings can not only develop a superior multi-performance eco-concrete material but also provide a promising strategy for sustainable riparian restoration.

Assessment of heavy metal contamination in groundwater and its implications for dental and public health

Groundwater contamination with heavy metals is a critical environmental issue, especially in regions heavily reliant on groundwater for drinking purpose. These metals can seep into groundwater from soil and rock weathering or through improper disposal of industrial waste and effluents. Access to safe drinking water is essential for maintaining public health. This study aimed to assess heavy metal contamination in groundwater and its implications for dental and public health. The objective of the study was to measure the concentration of the heavy metals in the dentine of extracted tooth of the study population. The study concurrently measured heavy metal concentrations in groundwater and tooth dentine samples, analyzing demographic profiles, heavy metal correlations, and underlying structures using Principal Component Analysis (PCA). The average level of heavy metals in the groundwater samples varied from 9.763 ± 3.362 μg/L for Cd to 3426.204 ± 875.264 μg/L for Fe. The mean concentrations (μg/g) in teeth dentine showed significant variations, with iron (Fe) ranging from 0.149 ± 0.03 μg/g in water purifiers to 4.62 ± 0.578 μg/g in local water sources. Similar variations were observed for other heavy metals across different water sources. Principal component analysis (PCA) revealed seven principal components, with the first two components explaining 96.1% of the total variance. The findings revealed varied concentrations of heavy metals across all water sources. Statistical analyses underscored the complex relationship between water sources and heavy metal contamination levels, highlighting the need for targeted interventions to improve water quality and mitigate health risks. The study highlights the urgent need for monitoring and mitigation efforts to ensure safe drinking water and mitigate health risks associated with heavy metal contamination.

Effects of low impact development on runoff pollution and water quality resilience in an urbanized estuary area

In urbanized estuary areas, water quality often deteriorates due to the impact of surface runoff or overflow during heavy rainfall events. Low impact development (LID) can mitigate this impact and improve water quality resilience. However, there were few studies on quantifying this effect of LID, particularly in estuary areas. In this study, water quality resilience is expressed as the abnormal rate of water quality during rainfall events and the time required for water quality to recover from abnormality to normal. In this study, a coupled Storm Water Management Model (SWMM) and Environmental Fluid Dynamic Code (EFDC) model is used to examine the effects of LID on runoff pollution and water quality resilience in the Shenzhen River estuary (including Shenzhen River and Deep Bay) in China. The results indicate that (1) The inflow volume into the estuary is not only affected by the drainage area but also by the service area and capacity of the sewer interception system; LID can reduce not only the stormwater runoff but also the overflow from the interception systems along rivers. (2) The marginal benefit of the LID proportion increase in pollution load reduction diminishes as the proportion of LID implementation increases. (3) LID can reduce the high value of pollution concentration caused by rainfall runoff; and the reduction effect on the rivers is greater than that on the bay. (4) The rivers and the estuary have a much higher abnormal rate than the inner bay and the outer bay; however, the estuary and the inner bay have longer recovery time than the rivers and the outer bay. The maximum abnormal rate, average abnormal rate, and recovery time of different indicators in the entire estuary area are decreased by 10%-189%, 6%-71%, and 0.8–1.1 cycles when the runoff from 80% of built-up area is treated by LID facilities; LID can significantly reduce abnormal rate of the rivers and recovery time of the inner bay. Therefore, the proposed metric and model can fully reflect the spatial variations in water quality resilience, and LID can enhance the water quality resilience of the urbanized estuary areas under rainfall.

Highly dispersed single-atom Fe and Fe3O4 clusters anchored hierarchical-pore carbon as efficient persulfate activation catalyst

The selective removal of Fe particles from carbonized Fe-MOFs presents an intriguing strategy for developing efficient peroxydisulfate (PDS) activators. It is commonly accepted that their outstanding performance is largely attributed to the high specific surface area/pore volume. However, our investigation into the structure–function relationship of these materials has revealed new insights. In this study, a highly dispersed single-atom Fe and Fe3O4 clusters anchored hierarchical-pore carbon (CM88-H) was obtained via post-acid treatment of carbonized MIL-88B (CM88). Various characterizations were comparatively conducted to highlight the beneficial effects of iron dissolution. The CM88-H/PDS system achieved a notable BPA degradation efficiency, with a reaction rate of 0.323 min−1, which is 3.94 times higher than that of the CM88/PDS system. DFT calculations indicate that the Fe3O4 clusters optimize the charge distribution around single-atom Fe, promoting favorable PDS adsorption and facilitating a higher oxidation state of CM88-H. As a result, BPA can be completely degraded within 10 min with 0.1 g/L CM88-H and 0.05 g/L PDS via both radical and non-radical pathways. The CM88-H/PDS/BPA system performs effectively under various conditions, with a general reduction in toxicity. Furthermore, the CM88-H/PDS system shows broad oxidation activity towards BPA substitutes and pollutants with high ionization potential (IP). Notably, the CM88-H sponge-based fixed-bed catalytic reactor demonstrated satisfactory BPA degradation, highlighting the promising application of CM88-H in water purification. This study provides a sustainable solution for water treatment and accelerates the practical application of powdered nanocatalysts to improve water quality.

Integrated respiratory toxicity of municipal wastewater to human bronchial epithelial cells and 3D bronchospheres

Respiratory symptoms have been reported in wastewater treatment workers and residents living close to sewage treatment plant. However, toxicological research about the respiratory hazards of municipal wastewater is scarce. The present study aims to gain insight into the comprehensive respiratory hazards induced by the contaminant mixtures in municipal wastewater. The integrated respiratory hazards of effluents from four secondary wastewater treatment plants (SWTPs), a tertiary wastewater treatment plant (TTP), and a constructed wetland (CW) were evaluated using normal human bronchial epithelial cells (NHBE) bioassay, and toxicity reduction efficiency of various treatment techniques was analyzed. Effluents caused cytotoxicity, oxidative damage, inflammation response with the increased levels of IL-6 and CXCL8, and impaired barrier integrity with decreased expressions of ZO-1 and occludin in NHBE. Further, the effluents inhibited the development of 3D bronchospheres, increased irregular surface and cell debris, and suppressed the formation of luminal structures. TTP E effluent significantly increased the expression of MUC5AC in bronchospheres. The integrated biomarker response (IBR) of the influent was removed by 40.2% at SWTPs, 18.2% at TTP, and 36.6% at CW, respectively. The IBR of the final effluents from SWTPs, TTP, and CW were 7.2, 7.7, and 7.7, respectively. Significant correlation with toxicity biomarkers was frequently observed for stearyl alcohol, o-cresol, phenanthrene, butylated hydroxytoluene, and dimethyl phthalate. The present study provided human relevant evidence concerning the adverse respiratory effects associated with discharge. The necessity for deep water treatment, performance optimization, and the potential means were suggested for improving water quality and protecting respiratory health.

In situ construction of Flowerlike bismuth oxide (BiO2-x)/N-rich carbon nitride (C3N5) S-scheme heterojunctions with enhanced structural defects for the efficient photocatalytic removal of tetracycline antibiotic and RhB

Efficient photocatalysts for the simultaneous removal of organic dyes and antibiotics are crucial for sustainable environmental management. In this study, we designed and synthesized a C3N5/BiO2-x S-type heterojunction photocatalyst with structural defects using a hydrothermal method, aimed at degrading both Rhodamine B (RhB) and tetracycline (TC). The degradation kinetic constants for RhB and TC were 0.0809 min−1 and 0.0535 min−1, respectively, showing improvements of 9.52 and 25.48 times over pure C3N5, and 2.90 and 1.49 times over BiO2-x. This enhanced performance is attributed to the unique electron transfer mechanism of the S-scheme heterojunction and the structural defects that facilitate efficient separation of electron-hole (e−-h+) pairs. Free radical trapping experiments indicated that the main reactive oxygen species (ROS) involved are ·O2− and h+. Additionally, electrochemical impedance spectroscopy (EIS) and transient photocurrent response (TPR) measurements confirmed improved separation and transfer of photogenerated e−-h+ pairs in the C3N5/BiO2-x heterojunction. The higher density of structural defects in C3N5/BiO2-x compared to individual BiO2-x counterparts enhances its ability to activate and photo-oxidize TC and degrade RhB. Consequently, C3N5/BiO2-x demonstrates significant potential as a photocatalyst for improving water quality.

Patterns and Drivers of CO2 and CH4 Fluxes in an Urbanized River Network and Their Response to Restoration

AbstractCarbon evasion from urban river networks becomes increasingly significant as urbanization accelerates. However, there remains a limited understanding of the overall carbon emission impact integrating CO2 and CH4 dynamics, particularly in response to ecological restoration efforts. In this study, we investigated patterns of fluvial CO2 and CH4 diffusive fluxes across an urban river network in Wuxi, China. Our results reveal that water quality variables, especially dissolved oxygen (DO) and phosphorus content, predominantly influence the variability of carbon emissions. These factors exhibit a stronger correlation with CO2 emissions compared to CH4, indicating a net increase in carbon emissions as water quality deteriorates. Seasonally, higher water temperatures, phosphate levels, and lower DO concentrations lead to increased carbon emissions during summer months. Spatially, areas with lower carbon emissions (averaged 86 mmol m−2 d−1 CO2 and 0.13 mmol m−2 d−1 CH4) are primarily situated near the lake and in river sections where significant water quality improvements have been achieved through ecological restoration efforts. Cluster analysis shows that over 60% of high‐carbon emission (averaged 162 mmol m−2 d−1 CO2 and 1.21 mmol m−2 d−1 CH4) sites in the study area have undergone ecological restoration, suggesting potential for further carbon emission reduction through enhanced restoration practices. Our findings underscore the importance of implementing carbon reduction strategies such as nutrient removal and aeration for oxygenation within water ecological restoration initiatives. Effective matching of restoration strategies holds further potential for mitigating carbon emissions from urban river networks.

Assessing the Impact of Riparian Buffer Systems on Water Quality Improvement and Infiltration Enhancement: Integration of SWAT-MODFLOW and SWAT-REMM

Objectives:This study aims to assess the effect of riparian buffer system on the water quality improvement and infiltration enhancement in the upper Sinduncheon watershed by integrating the SWAT-MODFLOW and SWAT- REMM models.Methods:The study focused on three subbasins in the upper Sinduncheon watershed. Streamflow and groundwater level were simulated and relevant parameters were calibrated using SWAT-MODFLOW. Subsequently, the calibrated parameters were applied to SWAT-REMM to evaluate the effects of riparian buffer systems on the reduction of NO3-N and Suspended Solids (SS) and the enhancement of water infiltration. Riparian buffer scenarios with varying widths (9m, 21m, 27m). Results and Discussion:The results showed that the riparian buffer system led to significant reductions in NO3-N and SS. Specifically, a subbasin with the widest buffer (27m) showed the highest reduction efficiency (82.6% for NO3-N and 99.6% for SS). However, in a subbasin, despite having a wider buffer than other subbasin, the reduction efficiency was lower due to the presence of channelized pollutant inflow areas. Additionally, the riparian buffer increased rainfall infiltration by approximately 13%, contributing to the stabilization of baseflow.Conclusion:This study demonstrates that riparian buffer systems can significantly improve water quality and increase water infiltration in the upper Sinduncheon watershed. Future research should focus on developing tailored riparian buffer strategies that consider regional characteristics such as pollutant inflow patterns, land cover, and topography.

Assessment of Water-Related Ecosystem Services and Beneficiaries in the Hainan Tropical Rainforest National Park

Tropical rainforests are of vital importance to the environment, as they contribute to weather patterns, biodiversity and even human wellbeing. Hence, in the face of tropical deforestation, it becomes exigent to quantify and assess the contribution of ecosystem services associated with tropical rainforests to the environment and especially to the people. This study adopted a nuanced approach, different from traditional economic valuations, to estimate the water-related ecosystem services (WRESs) received by the people from 2010 to 2020 in the Hainan Tropical Rainforest National Park (HTRNP). The study focused on water yield, soil conservation, and water purification using InVEST, the SCS-CNGIS model, and spatial analysis. The results show (1) significant land cover changes within the HTRNP, as forest decreased by 4433 ha and water bodies increased by 4047 ha, indicating the active presence of human activities. However, land cover changes were more pronounced within the 5 km buffer area around the HTRNP, suggesting the effectiveness of the tropical rainforest conservation efforts in place. (2) The water yield of the HTRNP in the years studied decreased by 307.03 km3, based on the water yields in 2010 and 2020, which were 5625.7 km3 and 5318.7 km3, respectively. (3) Change detection showed that runoff mitigation in the rainforest has a negative mean (−0.21), indicating a slight overall decrease in soil conservation and runoff mitigation in the rainforest from 2010 to 2020; however, the higher curve number indicates areas susceptible to surface runoff. (4) The ecological effectiveness of water purification to absorb and reduce nitrogen load was better in 2020 (145,529 kg/year), as it was reduced from 506,739 kg/year in 2010, indicating improved water quality. (5) Population growth is more pronounced in areas with high water yields. Overall, the proposed framework has shown that the water yield potential of the HTRNP can meet the water consumption demands of people and industries situated within the buffer area. However, analysis of the study shows that it does not meet the crop water requirements. This study provides insights for decision makers in identifying potential beneficiaries and the essence of effective area-based conservation measures, and the proposed framework can be applied to any area of interest, offering a different approach in ecosystem services assessment.

Inisiasi Pengolahan Air Embung dengan Teknologi Multimedia Filter (MMF) sebagai Solusi Air Bersih di Kabupaten Bojonegoro

Clean water and proper sanitation are fundamental human needs. Nganti Village, located in Ngraho Subdistrict, Bojonegoro Regency, faces significant drought and clean water shortages, particularly during the dry season. The water quality remains subpar despite the presence of springs and water reservoirs. Consequently, processing raw water from the village's reservoir can offer a viable solution. This service activity aims to harness water reservoirs as a clean water source through multimedia filter (MMF) technology. The activities, conducted from 2022 to the end of 2023, encompass four stages: socializing the program plans, constructing multimedia filters (MMF), installing the water treatment unit on-site, and evaluating water quality, followed by necessary follow-ups. The primary activities involve installing water treatment units with MMF technology in collaboration with village officials and the community. The treated water is then tested for quality at the IPB University laboratory. Test results indicate that MMF technology significantly improves water quality, reducing parameters such as Magnesium, Manganese, Calcium, Iron, and Phosphate by 25.8‒97.8%, thus meeting quality standards. However, some parameters, such as TSS, COD, and Zinc, still exceed quality standards, necessitating further processing. This advanced water treatment requires involvement from the local government, particularly in funding through community empowerment programs, to install advanced treatment units and provide operational support for these units.

Glyphosate Herbicide Impacts on the Seagrasses Halodule wrightii and Ruppia maritima from a Subtropical Florida Estuary

Seagrass meadows are among the most threatened ecosystems on Earth, with losses attributed to increasing coastal populations, degraded water quality and climate change. As coastal communities work to improve water quality, there is increased concern regarding the use of herbicides within the watersheds of these sensitive ecosystems. Glyphosate is the most widely used herbicide on Earth because it is non-selective and lethal to most plants. Also, the targeted amino acid synthesis pathway of glyphosate is not carried out by vertebrates, and it is generally considered one of the safer but effective herbicides on the market. At least partially due to its cost-effectiveness compared to other techniques, including mechanical harvesting, glyphosate use in the aquatic environment has increased in coastal areas to manage aquatic weeds, maintain navigable waterways and mitigate upland flooding. This has prompted concerns regarding potential ecosystem-level impacts. To test the acute toxicity of glyphosate to seagrasses, mesocosm experiments exposed Ruppia maritima and Halodule wrightii to 1 ppm, 100 ppm and 1000 ppm of glyphosate (as glyphosate acid). No significant decrease in leaf chlorophyll a (Chl a) was identified for either species at 1 ppm versus a control; however, significant decreases were observed at higher concentrations. In all except 1000 ppm mesocosms, water column Chl a increased, with a 7-fold increase at 100 ppm. These data demonstrate that at very high glyphosate concentrations, both acute toxicity and light limitation from enhanced algal biomass may have adverse impacts on seagrasses. Despite these observations, no significant adverse impacts attributed to acute toxicity were observed at 1 ppm, which is &gt;1000 times higher than concentrations measured in the Indian River Lagoon system. Overall, herbicide use and associated decaying biomass contribute nutrients to these systems, in contrast to the removal of nutrients when mechanical harvesting is used. Based on our data and calculations, when used at recommended application rates, contributions to eutrophication, degraded water quality and harmful algal blooms were more likely to impact seagrasses than acute toxicity of glyphosate.