INTRODUCTION
Water is an essential resource, particularly in river basins, where rivers, despite comprising only 0.2 percent of Earth's freshwater, play a crucial role Acting as natural highways, rivers transport water, sediment, organisms, and nutrients while draining rainwater and offering habitats for diverse plant and animal species However, increasing demands for both the quality and quantity of water, coupled with the rise in untreated wastewater, have led to severe pollution of water resources in many regions.
Across the globe, numerous river catchment management organizations have been established to ensure the integrated management of water, soil, and related resources Their primary goal is to enhance economic benefits and social welfare while preserving the sustainability of the environmental system within the catchment area, thereby maintaining essential environmental conditions for human life.
The Hieu River, a key waterway in Nghe An province, plays a vital role in the region's economic development and national security Its watershed, covering an area of 5,417 km², is crucial for the Lam River system However, increasing economic activities in the Hieu River catchment have led to unsustainable water resource usage, posing serious risks of pollution and potential ecological collapse To prevent the Hieu River from becoming a "dead" river, it is essential to implement sustainable management and protection measures that balance economic benefits with environmental preservation This thesis project, titled "Impacts of Economic Activities on the Water Quality of Hieu River in Chau Hanh Commune, Quy Chau District," aims to assess the current water quality and its relationship with land use, ultimately proposing solutions for sustainable development while ensuring environmental protection in the area.
RESEARCH OVERVIEW
Water quality indicators
Water quality management involves assessing the suitability of water for specific uses by evaluating its physical, chemical, and biological characteristics Key properties measured in water quality assessment include various indicators that determine its overall safety and usability.
The pH level of water plays a crucial role in determining the solubility and biological availability of essential nutrients and heavy metals, influencing aquatic life Extreme pH values can negatively impact water usability, while pollution can alter pH levels, posing significant risks to the health of aquatic animals and plants.
Dissolved Oxygen (DO) is a vital indicator of water quality, as it is essential for the survival of aquatic organisms in lakes, rivers, and oceans When DO levels fall below normal, water quality deteriorates, leading to the decline and death of aquatic life Measuring dissolved oxygen in surface water is crucial for evaluating the overall "health" of lakes and streams.
Total Suspended Solids (TSS) and Total Dissolved Solids (TDS) are crucial indicators of water quality, as environmental water can contain various impurities Understanding the concentrations of both TSS and TDS is essential for assessing water suitability for human consumption and other applications Notably, TSS, often referred to as "dirt," is one of the most prevalent pollutants globally.
Biochemical Oxygen Demand (BOD) quantifies the oxygen consumed by microorganisms during the breakdown of organic matter High BOD levels indicate that microorganisms are depleting oxygen resources, which can jeopardize the survival of larger aquatic animals that require ample oxygen.
Low Biochemical Oxygen Demand (BOD) indicates a high level of oxygen in the water, which contributes to excellent water quality BOD is a crucial indicator of water quality, directly linked to the overall health of aquatic ecosystems.
Chemical oxygen demand (COD) is an essential metric that quantifies the amount of oxygen consumed by water during the breakdown of organic matter and the oxidation of inorganic substances The COD test serves as an indirect assessment of organic compound levels in water, making it a valuable tool for evaluating water quality By measuring COD, we can effectively gauge the concentration of organic pollutants in surface waters such as lakes and rivers, as well as in wastewater.
This study emphasizes the significance of riparian buffers in promoting stream stability, enhancing pollutant removal, and supporting overall stream health Protecting existing riparian features and restoring degraded buffers can greatly improve water quality.
Literature reviews
Early research on river catchments in Vietnam has focused intensively on meteorology, hydrology, and geomorphology, laying a strong foundation for the recent advancements in water quality studies within these areas.
Vietnam boasts a dense network of rivers, featuring approximately 2,732 rivers longer than 10 kilometers, and encompassing 13 major river systems that span an area of 10,000 km² Notably, 10 of these river basins are trans-boundary, collectively covering 80% of the nation's territory The nine largest river systems, including the Red, Thai Binh, Bang Giang – Ky Cung, Ma, Ca, Thu Bon, Ba, Dong Nai, and Cuu Long rivers, represent 90% of the country's total river basins Each river basin is characterized by unique natural and water resource attributes, while management approaches differ based on socio-economic conditions, land use, and environmental factors.
Water quality is influenced by both natural factors and human activities Human actions not only modify the quantity of available water but also disrupt the balance of water components.
The hydrological regime of water in Vietnam is significantly affected by changes in water quality, as most rivers and lakes serve as both water sources and recipients of public sewage, industrial waste, and agricultural runoff Key economic activities impacting the quantity and quality of water resources include the demand for water for industrial and public use, sewage disposal, urbanization, construction of reservoirs, irrigation, and agricultural and forestry practices.
STUDY AREA
Natural conditions
Chau Hanh commune features a diverse terrain characterized by hills and numerous streams The area is home to eight significant streams, all originating from high mountains with steep slopes Notably, the Ke Ninh stream flows northward to the Hieu River in an east-west direction, while the Lan and Bong streams, sourced from Bu Xen Mountain (583m), flow towards the Hieu River in a southwest-northeast direction Additionally, the My and Minh Chau streams in the east arise from Tung Ca Mountain (625m) and Pu Nghin Mountain (435m).
Chau Hanh commune, located in the North Central climate region of western Nghe An, experiences a tropical monsoon climate characterized by hot and rainy conditions The area enjoys between 1,580 to 1,650 hours of sunshine annually, with an average temperature ranging from 24°C to 28°C and humidity levels between 80% and 86% The rainy season typically occurs from August to October, bringing annual rainfall totals of 1,700 to 2,000 mm, while the dry season spans from November to March.
Chau Hanh annual influenced by two main wind seasons:
- Southeast wind season starts from October last year to April of next year Characteristics of this period the dry, it is easy to cause fire in the autumn – winter
The Southeast wind season, occurring from April to June, brings hot weather, heavy rainfall, and high humidity This period is crucial for local communities as it marks the time for shifting cultivation activities.
Socio-Economic Conditions
Economic structure of Chau Hanh commune mainly focus on agriculture and forestry (85% of total proportion):
Farming: the total cultivation area is 900ha, of which: The area of paddy rice (2 seasons): 510 hectares; Corn planted area: 130 hectares; sweet potato, cassava planted area:
60 ha; Peanut Area: 15ha; vegetables, legumes, cattle feed crops area: 50ha and 135ha of sugarcane
Livestock: the commune has 7029 head of cattle, including: 2853 Buffalo; 1076 Cow: and 3100 Pig In addition, the commune has 27000 poultries and 12.5ha of aquaculture area
Chau Hanh commune encompasses 11,428.8 hectares of forest land, representing 90.1% of its total area Of this, 5,207.8 hectares are designated as production forest land, which constitutes nearly 50% of the commune's forested area Additionally, 4,191 hectares of the production forest are managed by families and individuals.
Industrial production in Chau Hanh commune is heavily influenced by the local availability of raw materials Key activities in the area include the extraction of construction materials, such as sand and building stone, as well as woodworking and carpentry.
Current service economy not yet developed much, mainly focus on transportation; hotels and restaurants services
Total households: 2105 households, including poor households (according to new criteria) are: 931 households (44%), 309 near- poor households (15%)
The rate of natural population growth each year: 1.25% / year
Ethnic composition: residents in the Chau Hanh commune mainly composed of three ethnic groups: Thai, Kinh, Tho Where Thai ethnic percentages over 80%
(Source: People's Committee of Chau Hanh commune)
GOALS AND OBJECTIVES
Goal
Propose solutions for environmental protection of the Hieu river watershed in Chau Hanh commune, Quy Chau district, Nghe An province.
Specific objectives
Objective 1: Assess the situation of water quality in the Hieu river in Chau Hanh commune, Quy Chau district, Nghe An province
Objective 2: Assess the impacts of economic activities to the changing in water quality of the Hieu river in Chau Hanh commune, Quy Chau district, Nghe An province
Objective 3: Propose possible solutions for sustainable watershed management in study area
METHODS
Data sources
To achieve the objectives, the thesis investigated the information on Chau Hanh commune to support for assessing water quality The information collected includes:
- Documents, survey data from People's Committee of Chau Hanh commune on natural conditions, socio-economic of the study area and the related reference
- Data on the natural environment such as forest area, water quality, land use, annual data about the characteristics of Hieu river from Quy Chau hydrology station
- Collect relevant documents, policies, management and protection of forest resources and water quality in the study area, the report on forest planning.
Data collection method
The thesis took samples at 12 points in the stream
All sample were taken at the:
- Depths: 30cm below the surface;
Time: 17 th August, all samples were taken in 2 hours 8.00 am – 10.00 am;
Figure 5.1 Sampling positions b Tools and sampling methods:
Tools and methods used for sampling follows the standards:
1 19°33'20.63"N 105° 3'29.15"E Before flow into the commune
12 19°33'33.71"N 105° 7'53.38"E After flow into the commune
1 TCVN 6663-1:2011 (ISO 5667-2: 2006) – Water quality- Sampling Part 1: sampling guides and techniques [13]
2 TCVN 6663-3:2008 (ISO 5667-3:2003) – Water quality- Sampling Guidelines of sample preserving and processing [14]
3 TCVN 6663-6:2008 (ISO 5667-6:2005) – Water quality - Sampling Sampling guidelines on rivers and streams [15]
Table 5.2 Limit values for surface water quality parameters – Follow QCVN 08:
A 1 - Good for domestic water and other purposes such as type A2, B1 and B2
A2 - For the purpose of domestic water, but must apply appropriate treatment technologies; conservation of aquatic flora and fauna, or using purpose as B1 and B2
B1 - For irrigation purposes or other similar purposes as type B2
B2 – Use for traffic other purposes with low water quality requirements
For effective sampling, ensure to use a clean 500ml bottle, rinsing it three times with water at the sampling location Additionally, prepare essential materials such as tapes, markers, paper labels, sealed barrels, and sponges for a thorough sampling process.
- Preserving and transporting of samples:
All bottled water samples must be cooled to approximately 4°C and transported to the laboratory, where target pH, temperature, and TDS are measured on-site Samples should be kept cold and stored in a dark place, as they typically remain viable for up to 24 hours.
5.2.2 Analysis of water samples collected:
Used a thermometer directly at the sampling location and record the results
Follow the standard TCVN 6492: 2011 – Water quality – Determination of pH PH was measured by pH-meter to determine the pH of water
Follow TCVN 7325:2004 (ISO 5814:1990) Water quality – Determination of dissolved oxygen Electrochemical probe method
Use Electrochemical sensor to analysis dissolved oxygen
4 Total Suspended Solid (TSS) measurement:
Follow TCVN 6625:2008 -Water quality- Determination suspended solids by filtration through glass-fibre filters
Used vacuum filter machine or pressure machine to filtering water samples through glass fiber filter Drying at 105 0 C and determine the sediment by scale
To prepare a glass fiber filter disk, first, place the disk onto the base and secure it with a funnel While applying vacuum, wash the disk with three consecutive 20 ml volumes of reagent water, ensuring all water is removed by maintaining vacuum after the water has passed through Next, dry the disk in an aluminum dish at a temperature of 103°C to 105°C for one hour Once dried, carefully remove the dish from the oven, allow it to desiccate, and then weigh it while still in the dish.
Re-dry and re-weigh filter until weight change is less than 0.5 mg
Select a sample volume (max of 200 ml) that will yield no more than 200 mg of total suspended solids
Place the filter on the base and clamp on funnel and apply vacuum Wet the filter with a small volume of reagent water to seal the filter against the base
Continuously stir the sample during sub-sampling and use a 100 ml graduated cylinder for quantitative transfer to the filter After the sample has passed through, ensure all water traces are removed by maintaining vacuum application.
Rinse the graduated cylinder onto the filter Remove all traces of water by continuing to apply vacuum after water has passed through
Carefully remove the filter from the base Dry at least one hour at 103 0 C -105 0 C Cool in a desiccator and weigh
Re-dry and re-weigh filter until weight change is less than 0.5 mg
Calculate Total Suspended Solids as follows:
A = weight of filter and dish + residue in mg
B = weight of filter and dish in mg
C = volume of sample filtered in ml
5 Total Dissolved Solid (TDS) measurement:
Use TDS measuring instrument to measure the amount of dissolved solid directly at the sample positions
6 Biological Oxygen Demand (BOD) measurement:
The analyzed samples exhibited significantly high levels of BOD5, necessitating dilution to an appropriate factor prior to assessment The water used for dilution was saturated with oxygen and enriched with essential nutrients.
To determine the biochemical oxygen demand (BOD), the sample was first diluted and the initial dissolved oxygen (DO0) was measured at 20°C The sample was then incubated for five days in a BOD-specific environment at the same temperature After incubation, the final dissolved oxygen (DO5) was measured, and the BOD5 value (in mg/L) was calculated by subtracting the BOD5 values of the blank sample from the final measurement.
BOD5: BOD values after 5 days (mg/L)
DO 0 : DO values at 20 0 C after diluting (mg/L)
DO5: DO values at 20 0 C after 5 days incubating at 20 0 C (mg/L)
7 Chemical Oxygen Demand (COD) measurement:
TCVN 6491:1999 (ISO 6060:1989) outlines the method for determining Chemical Oxygen Demand (COD) in water quality analysis This process involves oxidizing organic matter using a boiling mixture of chromic and sulfuric acids, where a sample is refluxed in an acidic solution with a known excess of potassium dichromate (K2Cr2O7) After digestion, the remaining K2Cr2O7 is titrated with ferrous ammonium sulfate to calculate the oxidizable matter as oxygen equivalent It is important to maintain constant ratios of reagent weights, volumes, and strengths when using sample volumes other than 50 ml The standard reflux time of 2 hours may be shortened if validated by consistent results, and samples with low COD or heterogeneous solids may require replicate analyses for reliable data.
16 enhanced by re-acting a maximum quantity of dichromate, provided that some residual dichromate remains
Directly interview 30 people, mainly focus on:
People who has farmland near the riverbanks, question designed about:
- Do they use river water as domestic water?
- Type of farming (plantation forest, rice, maize…)
- Their cultivation methods (Do they burn the forest? Do they use plant protection products?)
Interview people who have jobs or economic activities, who concern about the river (boatman, meteorological station staff…) about their comments about the changes, evolutions of the river
Table 5.3 Interviewing information on economic activities on Hieu River in Chau Hanh commune:
Name Address Type of farming Area of farm land Cultivation methods
Data analysis method
Statistical table about the water quality properties which measured and data table of interviewing result
Analyze and evaluate the data obtained, compare with the published documents
Comparison of changes in water quality before and after going through the study area Analyze data by Excel software
RESULTS AND DISCUSSION
Flow characteristics of Hieu river in study area
Data on the characteristics of temperature; discharge and suspended load were recorded by Quy Chau hydrology station Data are presented in the following table:
Table 6.1 Some water indicator of Hieu river in Chau Hanh commune from the year
Data Source: Quy Chau hydrology stations
Statistical results from Quy Chau hydrology station show that: flow characteristics of Hieu river changes every year In which:
- Temperature of water in Hieu river from the year 2008 to 2015 tended to increase:
Figure 6.1.The analytical result of temperature from the year 2008 to 2015
- Average flow discharge and the suspended solids changes in the same direction and tended to decrease:
Figure 6.2.The analytical result of average discharge from the year 2008 to 2015
Water quality
The thesis took samples at 12 points in the stream
Data are presented in the following table:
A ver age di sc ha rg e (m 3/ s)
Table 6.2 Analysis indicator of Hieu river in Chau Hanh commune:
Time: 17 th August, all samples were taken in 2 hours 8.00 am – 10.00 am;
6.2.1 pH pH parameter of Hieu river water in Chau Hanh commune ranged from 6.7 to 7.8, averaging about 7.2, satisfy with required quality of surface water for domestic purpose
Measured values of DO in study area are shown in the following graph:
Figure 6.4 The analytical result of DO
The study reveals that the average Dissolved Oxygen (DO) level of the Hieu River water meets the A2 standard for domestic use However, upon entering Chau Hanh commune, the DO level decreases from 5.62 mg/L to 4.99 mg/L.
Measured values of TDS in study area are shown in the following graph:
DOA1 - QCVNA2 - QCVNB1 - QCVNLinear (DO)
Figure 6.5 The analytical result of TDS
The average Total Dissolved Solids (TDS) value of the Hieu River is low at approximately 20.3 mg/L, significantly below the acceptable aesthetic threshold of 500 mg/L for drinking water Most aquatic ecosystems with diverse fish species can tolerate TDS levels up to 1000 mg/L Additionally, upon entering the Chau Hanh commune, the Dissolved Oxygen (DO) levels increased from 19.1 mg/L to 21.2 mg/L.
Measured values of TSS in study area are shown in the following graph:
Figure 6.6 The analytical result of TSS
The Hieu River in the study area is significantly polluted with suspended solids, particularly in the Chau Hanh commune, where the levels of this indicator are alarmingly high.
22 and ranging from 713 mg/L to 895 mg/L These values are higher about 7-8 times than the standards of QCVN 08-MT: 2015/BTNMT
Measured values of BOD5 and COD in study area are shown in the following graphs:
Figure 6.7 The analytical result of BOD 5
Figure 6.8 The analytical result of COD
The water quality analysis of Hieu River in Chau Hanh commune reveals elevated levels of BOD5 and COD, surpassing established standards Specifically, BOD values range from 29.2 to 38.8 mg/L, exceeding B2 standards by approximately 1.2 to 1.5 times Additionally, COD levels are also found to be higher than acceptable limits, indicating significant pollution in the river.
23 about 2 – 3 times than the B2 standard, ranging from 97 to 143 mg/L Both values of BOD5 and COD increased after flow into Chau Hanh commune
The Hieu River's water quality has deteriorated after entering Chau Hanh commune, rendering it unsuitable for domestic use While pollution levels are not critically high, the water can only be utilized for irrigation purposes.
Economic activities of study area in Hieu River
Economic activities is the main reason that reduce land cover in the riparian buffer of Hieu river in Chau Hanh commune
Figure 6.9 Map of plant cover in study area
The map indicates that the land cover density in the riparian buffer of the Hieu River is lower compared to other areas in Chau Hanh commune This is likely due to the proximity to the water source, which promotes production activities However, the loss of vegetation on both sides of the river may lead to significant changes in water quality.
From the collected documents and interview survey, the economic activities in Chau Hanh commune are:
The riparian area of the Hieu River in Chau Hanh commune is predominantly comprised of farmland Interviews with local residents reveal that their understanding of the environment is quite limited.
Shifting cultivation is the primary agricultural method practiced by local communities, involving the selection of arable land adjacent to forests for slash-and-burn techniques to cultivate crops such as rice, cassava, and maize This forest clearing contributes to soil erosion and a decrease in forest cover In the post-harvest phase, farmers burn leftover vegetation to enhance soil nutrients, fostering microorganism development and accelerating land reclamation However, these agricultural practices can negatively affect water quality by releasing nutrients and chemicals, including pesticides, into the water system through biological contamination from manure and soil erosion.
Interviews with residents of Chau Hanh commune, located near the Hieu River, reveal that most families own between 2 to 10 cattle, which are primarily fed through free grazing This grazing method, particularly along the riverbank, negatively impacts the vegetation in the riparian buffer of the Hieu River.
Chau Hanh commune lacks an industrial zone and primarily features a few forest product processing facilities However, disorganized mining activities along the Hieu River are significantly contributing to water pollution in the area In addition to deforestation for agricultural purposes, these mining operations are among the primary causes of environmental degradation in the region.
Mining activities in Chau Hanh commune contribute to 25% of Total Suspended Solids (TSS) pollution in the Hieu River, altering soil structure and increasing the risk of landslides and riverbank erosion.
Chau Hanh commune's trade and services are primarily small-scale, with development investments lacking integration The main service sectors, healthcare and transportation, currently have minimal environmental impact However, there is insufficient focus on waste collection and treatment within these services, which poses a risk of significant long-term environmental consequences.
Sand mining activity in Hieu River (Source:
Gold mining activity in Hieu River (Source:
Roads near Hieu river (Source: field survey) Soil erosion in Hieu river bank (Source: field survey)
Nature forest in Hieu river (Source: field survey) Swidden land in Hieu river (Source: field survey)
Farmland in Hieu river (Source: field survey) Cattle in Hieu river (Source: field survey)
Efects of land use on water quality
During sampling process, the characteristics of land use in the riparian buffer near each sampling location has been recorded Recorded results are presented in the following table:
Table 6.3 Characteristics of sample location
The results show that: in the total of 12 sampling locations, 5 locations near the forest land, 5 locations near the farmland and 2 locations near roads
Compare with analysis indicator in table 6.1.2, we have table below:
Table 6.4 Analysis of water indicators and sampling locations
Comparison results of each indicators show that:
- DO: the average value of DO in samples which near forest land is highest and smallest in the samples which near roads
- TDS, TSS, BOD5 and COD in sample which near roads are highest and smallest in the sample which near forest lands
Figure 6.10 Analytical results of water indicators and sampling locations
Comparison result of water quality in 3 different types of land use show that:
Water samples collected near agricultural land and roads exhibit lower quality compared to those from forested areas, likely due to the higher land cover in forests Heavy rainfall in Nghe An province during the sampling period exacerbated the situation, as the loss of forest cover from farmland and road development has led to increased human-accelerated erosion, further degrading the water quality of the Hieu River Additionally, agricultural practices can directly impact water quality through the runoff of soil, nutrients, and pesticides into nearby watercourses during rain events.
Water samples collected near roads exhibit the lowest quality due to several factors, including low plant cover density and the direct impact of dust and waste from vehicles on river water quality.
DO (mg/L) TDS (mg/L) TSS (mg/L) BOD5 (mg/L) COD (mg/L)
Axis Title Forest land Farm land Roads
Solutions to improve water quality and sustainable water use in the study area
To improve water quality and sustainable water use in Chau Hanh commune, the thesis propose that commune authorities need to promulgate the following policies:
- Stricty forbidden all illegal mining activities on Hieu river
- Forest protection policy, especially riparian forest
- Policies to encourage economic development in forestry, sustainable farming on slopes
6.5.2 Solutions on land use and land planning
The decline of forest resources significantly impacts water quality and contributes to the depletion of water resources in the Hieu River Current surveys indicate that the remaining forest area along the river's riparian buffer is minimal This thesis emphasizes the importance of reforestation solutions, including the regeneration and protection of existing forests, nurturing and enriching current forest areas, and implementing new planting initiatives to restore and regenerate forest cover along the riparian buffer.
The regeneration and protection of existing forests is a vital solution for reforestation, utilizing natural regeneration in suitable areas Effective measures include prohibiting grazing and logging in regeneration zones to safeguard young plants, while empowering local communities with management responsibilities, complemented by regular oversight Additionally, implementing fire prevention strategies is crucial, as shifting cultivation practices pose significant risks to forest health To mitigate these threats, it is essential to enforce policies against forest burning and educate local populations on the importance of forest conservation.
This is an in expensive solution but create high ecological benefit
Nurturing and enriching forests involves promoting woody plants that enhance land quality and support biodiversity Key species such as Melia azedarach, Acacia auriculiformis, and Cinnamomum cassia are vital for their strong regenerative capabilities and ability to thrive in native ecosystems.
- New planting and regenerate forest areas on the riparian buffer: application objects is the bare hills, bare land where plants are destroyed by forest fire
In the areas of farmland, tree should be planted into the riparian trips to reduce the erosion, encourage people to restricted use of plant protection products…
Regularly monitored and evaluate water quality in study area
The environmental monitoring system for surface water quality aims to evaluate the effects of human activities on water quality and its suitability for various uses.
- Application of new technologies in the field of drinking water treatment and processing, wastewater treatment of production before being discharged into the river
- Build a database of environmental monitoring by applying GIS and modeling to forecast the changing in water quality of the whole Hieu river basin
CONCLUSION
The findings indicate a declining trend in the average flow discharge of the Hieu River Additionally, the water quality in Chau Hanh commune does not meet acceptable standards, with Total Suspended Solids (TSS), Biochemical Oxygen Demand (BOD), and Chemical Oxygen Demand (COD) exceeding the B2 standard as per QCVN regulations Consequently, Hieu River water is unsuitable for domestic use and can only be utilized for irrigation purposes.
Research on the effects of economic activities on the water quality of the Hieu River in Chau Hanh commune reveals a clear connection between land use characteristics, particularly in the riparian buffer zone, and water quality Specifically, the presence of built-up areas such as roads, along with farmland and forest land, significantly impacts water quality, often leading to deterioration However, findings indicate that enhancing plant cover can positively influence and improve water quality.
The thesis outlines several strategies to enhance water quality and promote sustainable use in the study area, including policy solutions, land use planning, and technical approaches Among these, the most effective long-term solution for improving the water quality of the Hieu River in Chau Hanh commune is to increase the forested area.
This study offers valuable insights for optimizing land use and controlling water pollution in rural and mountainous regions of Vietnam, aiding in the development of policies that balance water resource exploitation and protection It specifically examines how economic activities influence water quality, while also acknowledging the significant roles of climate, precipitation, and population density in affecting water quality outcomes.
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