INTRODUCTION
Water is an essential resource, particularly in river basins, where rivers, despite comprising only 0.2 percent of the Earth's freshwater, play a crucial role Acting as natural highways, rivers transport water, sediment, organisms, and nutrients, while also draining rainwater and providing habitats for diverse plant and animal species However, the growing demand for quality and quantity of water, coupled with the rising levels of untreated wastewater, has led to significant pollution of water resources in many areas.
Around 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 maximize economic benefits and enhance social welfare while preserving the sustainability of the environmental systems within the catchment area, thereby maintaining the essential environmental conditions for human life.
The Hieu River, a significant waterway in Nghe An province, plays a crucial role in the region's economic development and national security, with its watershed covering an area of 5,417 km² However, rapid economic growth in the districts surrounding the Hieu River has led to unsustainable water resource use, increasing the risk of water pollution and potential ecological collapse Without effective management and protection measures, the Hieu River could face severe degradation Therefore, it is imperative to restore the river's health while balancing economic benefits and social welfare with environmental sustainability This thesis project, titled “Impacts of Economic Activities on the Water Quality of Hieu River in Chau Hanh Commune, Quy Chau District, Nghe An Province,” aims to assess the current water quality and its relationship with land use, ultimately proposing solutions for sustainable economic development that prioritize environmental protection in the area.
RESEARCH OVERVIEW
Water quality indicators
Water quality management assesses the suitability of water for specific uses by evaluating its physical, chemical, and biological characteristics Key properties measured in water quality include various parameters that determine its overall health and usability.
The pH level of water is crucial as it influences the solubility and biological availability of essential nutrients like phosphorus, nitrogen, and carbon, as well as heavy metals such as lead and cadmium Extreme pH levels can negatively impact water usability, and pollution can alter a water body's pH, posing risks to aquatic life and ecosystems.
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, it negatively impacts water quality, leading to the decline 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 critical 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 the most prevalent pollutant globally.
Biochemical Oxygen Demand (BOD) quantifies the oxygen consumed by microorganisms during the breakdown of organic matter A high BOD indicates that microorganisms are depleting oxygen levels, which can jeopardize the survival of larger aquatic animals that require significant amounts of oxygen.
Low Biochemical Oxygen Demand (BOD) indicates a high level of dissolved oxygen, contributing to excellent water quality BOD is a crucial indicator of water quality, directly reflecting the ecological health of aquatic environments.
Chemical oxygen demand (COD) quantifies the ability of water to consume oxygen while decomposing organic matter and oxidizing inorganic chemicals The COD test serves as an indirect assessment of organic compound levels in water, making it essential for evaluating water quality Its applications include measuring organic pollutants in surface water bodies like lakes and rivers, as well as in wastewater, highlighting its significance in environmental monitoring.
This study emphasizes the significance of riparian buffers in enhancing stream stability, removing pollutants, and preserving stream health Maintaining and restoring these vital features can significantly improve water quality.
Literature reviews
Early research on river catchments in Vietnam has laid a strong foundation, particularly in meteorology, hydrology, and geomorphology This initial work has significantly advanced recent studies focused on water quality in these river catchments.
Vietnam features a complex river network, with approximately 2,732 rivers exceeding 10 kilometers in length, 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 possesses unique natural resources and water characteristics, leading to varied management approaches influenced by socio-economic conditions, land use, and environmental factors.
Water quality is influenced by both natural factors and human activities Human impacts on water resources not only modify the quantity of water available but also disrupt the balance of various water components.
The hydrological regime in Vietnam is significantly impacted by various economic activities that affect both the quantity and quality of water resources Major contributors include the demand for water for industrial and public use, the discharge of sewage, urbanization, the construction of reservoirs, irrigation practices, and agricultural and forestry production Rivers and lakes serve as vital sources of water supply while also receiving pollutants from these activities.
STUDY AREA
Natural conditions
Chau Hanh commune features a rugged landscape characterized by numerous hills and streams This locality is home to eight distinct streams, all originating from high mountains with steep slopes Notably, the Ke Ninh stream flows from north to south into the Hieu River, while the Lan and Bong streams, sourced from Bu Xen Mountain (583m), flow towards the Hieu River in a southwest to northeast direction Additionally, the My and Minh Chau streams in the east are derived from Tung Ca Mountain (625m) and Pu Nghin Mountain (435m).
Chau Hanh commune, situated in the North Central climate region of western Nghe An, experiences a tropical monsoon climate characterized by hot and rainy conditions It receives between 1,580 and 1,650 hours of sunshine annually, with average temperatures ranging from 24°C to 28°C and humidity levels between 80% and 86% The rainy season spans from August to October, bringing annual rainfall totals of 1,700 to 2,000 mm, while the dry season lasts 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, marking a critical period for local communities engaged in shifting cultivation.
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 Among this, 5,207.8 hectares are designated as production forest land, which constitutes nearly 50% of the commune's forest resources Additionally, 4,191 hectares of the production forest area are managed by families and individuals.
Industrial production in Chau Hanh commune is significantly influenced by the local availability of raw materials Key activities include the extraction of construction materials such as sand and building stone, along with woodworking and carpentry services.
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
B 1 - For irrigation purposes or other similar purposes as type B2
B2 – Use for traffic other purposes with low water quality requirements
When sampling, ensure the clean bottle has a 500ml capacity and is properly rinsed three times with water at the sampling location Additionally, gather essential materials such as tapes, markers, paper labels, sealed barrels, and sponges to facilitate the sampling process effectively.
- Preserving and transporting of samples:
All bottled water samples must be cooled to approximately 4°C and transported to the laboratory, where specific parameters such as pH, temperature, and TDS are measured on-site It is essential to store the samples in a cool, dark place, as they typically remain viable for analysis 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, rinse the disk with three consecutive 20 ml volumes of reagent water, ensuring all water is removed by maintaining vacuum after rinsing Next, dry the disk in an oven at a temperature of 103-105°C for one hour in an aluminum dish When ready to use, take the dish from the oven, allow it to desiccate, and then weigh the disk 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 traces of water 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 BOD 5, necessitating dilution to an appropriate factor prior to testing To ensure accurate results, the water used for dilution was saturated with oxygen and supplemented with essential nutrients.
To determine the Biochemical Oxygen Demand (BOD5), we first diluted the sample and measured the Dissolved Oxygen (DO) at 20°C The sample was then incubated in a BOD-specific pocket at the same temperature for five days After the incubation period, we re-measured the DO value, and the BOD5 was calculated by subtracting the BOD5 values of the blank sample from the measured DO values.
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 a strongly acidic solution with an excess of potassium dichromate (K2Cr2O7) After digestion, the unreduced K2Cr2O7 is titrated with ferrous ammonium sulfate to quantify the consumed K2Cr2O7 and calculate the oxidizable matter in terms of oxygen equivalent It is essential to maintain consistent ratios of reagent weights, volumes, and strengths when using sample volumes other than 50 ml The standard reflux time of 2 hours can be shortened if validated by equivalent results, and samples with low COD or heterogeneous solids may require duplicate analysis for accuracy.
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:
Av era ge d is ch ar ge (m 3/s )
Su sp en d ed s o lids (m g/L)
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 in the Hieu River water meets the A2 standard, which is suitable for domestic use However, there is a noticeable decline in DO levels after the water flows into Chau Hanh commune, dropping 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, well 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 Chau Hanh commune is significantly polluted, primarily due to high levels of suspended solids This alarming concentration of suspended solids indicates a serious environmental concern for the river's water quality.
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 study indicates that the BOD5 and COD levels in the Hieu River water at Chau Hanh commune exceed established standards Specifically, BOD values are elevated by approximately 1.2 to 1.5 times the B2 standards, measuring between 29.2 and 38.8 mg/L Additionally, COD levels are also found to be higher than permissible limits.
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 flowing into Chau Hanh commune, resulting in pollution levels that, while not excessively high, render the water unsuitable for domestic use Consequently, this water source is limited to irrigation purposes only.
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 than in other areas of Chau Hanh commune This is likely due to the proximity to the water source, which promotes agricultural activities However, the reduction of vegetation on both sides of the river may lead to adverse changes in water quality.
From the collected documents and interview survey, the economic activities in Chau Hanh commune are:
The Hieu River in Chau Hanh commune is predominantly surrounded by farmland, yet local residents possess limited environmental awareness regarding this riparian area.
Shifting cultivation is the primary agricultural method practiced by local communities, involving the selection of arable land near forests for slash-and-burn techniques to grow crops like rice, cassava, and maize This practice leads to soil erosion and a reduction in forest cover After harvest, farmers often burn leftover crops to enrich the soil with nutrients, promoting microbial development and facilitating land reclamation However, agricultural activities can adversely affect water quality by releasing nutrients and chemicals, such as pesticides, into the water environment through biological contamination and erosion from farmland.
In Chau Hanh commune, residents living near the Hieu River typically own between 2 to 10 cattle, primarily grazing them freely along the riverbank This method of livestock management negatively impacts the vegetation in the riparian buffer of the Hieu River, highlighting the need for sustainable grazing practices to protect the local ecosystem.
Chau Hanh commune lacks an industrial zone, featuring only a few forest product processing facilities However, disorganized mining activities along the Hieu River have led to significant water pollution In addition to deforestation for agricultural purposes, these mining operations are a primary contributor to the environmental degradation in the area.
Mining activities in Chau Hanh commune contribute to 25% of TSS pollution in the Hieu River, significantly impacting water quality Additionally, these activities alter soil structure, increasing the risk of landslides and riverbank erosion.
Chau Hanh commune's trade and service sectors are still small-scale and lack integrated development investments Currently, healthcare and transportation dominate the service landscape, with minimal environmental impact However, the insufficient focus on waste collection and treatment in these business activities poses a long-term risk to the environment.
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 quality samples collected near agricultural land and roads are significantly lower than those taken near forested areas, likely due to the higher land cover in forests Following heavy rainfall in Nghe An province, the loss of forest cover from agricultural and road development has intensified human-accelerated erosion, further degrading the water quality of the Hieu River Additionally, agricultural practices contribute to water quality decline as soil, nutrients, and pesticides are washed into watercourses during rainfall events.
Water samples collected near roads exhibit the lowest quality due to several factors, including low plant cover density Additionally, dust and waste from vehicles significantly contribute to the deterioration of 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 the depletion of water resources in the Hieu River Survey results indicate that the remaining forest area in the river's riparian buffer is minimal Consequently, this thesis proposes reforestation solutions, including the regeneration and protection of existing forests, nurturing and enriching current forest areas, and the establishment of new plantings to restore the riparian buffer.
The regeneration and protection of existing forests is a vital solution for reforestation, emphasizing natural regeneration in suitable areas Effective strategies include prohibiting grazing in regeneration zones and restricting tree cutting in protected areas Assigning management responsibilities to local communities has proven beneficial, provided there is regular oversight Additionally, implementing fire prevention and firefighting measures is crucial, as shifting cultivation practices among locals pose significant risks to forest health To combat this, policies prohibiting forest burning must be enforced, alongside educational initiatives to raise awareness about the importance of forests.
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 ecological balance Key species for this initiative include native trees with strong regenerative capabilities, such as Melia azedarach, Acacia auriculiformis, and Cinnamomum cassia.
- 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 evaluates 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, while the water quality in Chau Hanh commune fails to meet acceptable standards Key indicators such as Total Suspended Solids (TSS), Biochemical Oxygen Demand (BOD), and Chemical Oxygen Demand (COD) exceed the B2 standard as per QCVN regulations Consequently, the water from the Hieu River is unsuitable for domestic use and can only be utilized for irrigation purposes.
Research on the economic activities affecting the water quality of the Hieu River in Chau Hanh commune reveals a strong correlation between land use characteristics, particularly in the riparian buffer zone, and water quality The presence of built-up areas, farmland, and forest land significantly impacts water quality, often leading to negative changes However, findings indicate that enhancing plant cover can positively influence and improve water quality.
The thesis presents several solutions aimed at enhancing water quality and promoting sustainable use in the study area, including policy recommendations, land use planning strategies, and technical solutions Among these, the most effective long-term strategy for improving the water quality of the Hieu River in Chau Hanh commune is the expansion of forested areas.
This study offers valuable insights for optimizing land use and controlling water pollution in rural and mountainous areas of Vietnam, aiding in the development of policies that balance water resource exploitation and protection It specifically examines the effects of economic activities on water quality, while also acknowledging the influence of various factors such as climate, precipitation, and population density on water quality.
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