INTRODUCTION
Water is an essential resource, especially within river basins, where it plays a vital ecological and economic role Although river water accounts for only about 0.2% of the world's fresh water, it is crucial for transporting sediment, nutrients, and supporting diverse ecosystems Rivers act as natural routes that drain rainwater and serve as habitats for numerous plant and animal species However, increasing water demands for various human activities, coupled with the rising disposal of untreated wastewater, have led to significant pollution issues in many areas, threatening the sustainability of water resources.
Today, hundreds of river catchment management organizations have been established worldwide to promote integrated management of water, soil, and related resources within river catchments Their goal is to maximize economic benefits and social welfare while ensuring the sustainability of environmental systems These organizations focus on maintaining ecological conditions vital for human life and preventing environmental degradation, fostering a balanced approach to resource use and conservation.
Hieu River is a major waterway in Nghe An province, with its watershed covering 5,417 km² in the northwest, playing a crucial role in regional economic development and national security As an important part of the Lam River system, the watershed has seen increased resource utilization for rapid economic growth, leading to the risk of water pollution and potential river degradation Without proper management and protection, Hieu River Risks becoming a "dead" river in the near future Restoring the river’s health and implementing sustainable catchment management are urgent priorities to balance economic benefits with environmental protection This has motivated the research project titled “Impacts of Economic Activities on Water Quality of Hieu River in Chau Hanh Commune, Quy Chau District,” aiming to assess current water quality, analyze land use impacts, and propose sustainable development solutions that safeguard both economic growth and environmental integrity.
RESEARCH OVERVIEW
Water quality indicators
Water quality management involves assessing the suitability of water for specific uses by analyzing key physical, chemical, and biological characteristics Monitoring these properties is essential to ensure safe, clean, and effective water for various applications, highlighting the importance of comprehensive water quality measurements for effective management.
The pH level of water critically influences the solubility and biological availability of essential chemical constituents like nutrients (phosphorus, nitrogen, and carbon) and heavy metals (lead, copper, cadmium, etc.) Maintaining an appropriate pH is vital, as excessively high or low pH levels can negatively impact water quality and aquatic life Pollution can alter a water body's pH, potentially causing harm to the animals and plants that depend on it for survival.
Dissolved Oxygen (DO) is a vital indicator of water quality, as it reflects the health of aquatic ecosystems The oxygen dissolved in lakes, rivers, and oceans is essential for the survival of aquatic organisms When dissolved oxygen levels decline below normal thresholds, water quality deteriorates, leading to the death of marine life Measuring DO in surface water provides valuable insights into the overall health and ecological balance of lakes and streams, making it a key parameter for environmental assessment.
Total Suspended Solids (TSS) and Total Dissolved Solids (TDS) are key indicators of water quality, representing the solid and dissolved impurities present in environmental water sources Monitoring these parameters is essential, especially when assessing water for human consumption or other applications, to ensure safety and compliance with health standards Among the various pollutants, “dirt” in the form of TSS is the most common contaminant worldwide, highlighting the importance of managing and reducing suspended solids in water treatment processes.
Biochemical Oxygen Demand (BOD) measures the amount of oxygen microorganisms consume to oxidize organic matter in water High BOD levels indicate that microorganisms are using most of the available oxygen, which can threaten the survival of larger aquatic animals that require sufficient oxygen to thrive Elevated BOD levels often signal pollution or high organic waste loads in water bodies, impacting aquatic ecosystems' health and biodiversity Monitoring BOD is essential for assessing water quality and ensuring healthy, sustainable aquatic environments.
Low BOD levels indicate an abundance of oxygen, contributing to superior water quality As a critical water quality parameter, BOD reflects the organic matter in water and directly impacts the health of the aquatic ecosystem [5] Maintaining low BOD is essential for ensuring healthy, balanced water bodies.
Chemical Oxygen Demand (COD) measures the water's capacity to consume oxygen during the breakdown of organic and inorganic substances The COD test is a widely used method to indirectly assess the concentration of organic pollutants in water It plays a crucial role in evaluating water quality by determining the levels of organic matter in surface water bodies like lakes and rivers, as well as in wastewater treatment processes.
Riparian buffers play a crucial role in maintaining stream stability, effectively removing pollutants, and supporting overall stream health Protecting the integrity of these buffers and restoring degraded ones can significantly enhance water quality Incorporating healthy riparian buffers into watershed management promotes ecological balance and sustainability.
Literature reviews
Early research on Vietnam's river catchments primarily focused on meteorology, hydrology, geomorphology, and topography, laying a solid foundation for advancing water quality studies In recent years, these initial findings have supported the development of more comprehensive and sophisticated water quality research within river catchments across Vietnam.
Vietnam features a dense river network, with approximately 2,732 rivers exceeding 10 km in length, encompassing 13 major river systems covering a total area of 10,000 km² These 13 river basins, including 10 trans-boundary systems, together span 80% of the country's territory The nine largest river basins—Red, Thai Binh, Bang Giang – Ky Cung, Ma, Ca, Thu Bon, Ba, Dong Nai, and Cuu Long—constitute 90% of Vietnam’s total river resources Each river basin possesses unique natural resources and water characteristics, with management approaches tailored to local socio-economic, land use, and environmental conditions.
Water quality is influenced by both natural factors and human activities Human impacts on water resources can reduce water quantity and significantly alter the components of the water balance These changes can lead to pollution and degradation of water quality, affecting ecosystems and human health Effective management and pollution control are essential to maintain water quality and ensure sustainable water resources.
Vietnam’s rivers and lakes are vital water sources that are increasingly impacted by changing hydrological regimes and water quality issues Major economic activities such as industrialization, urbanization, agriculture, and forestry significantly influence both the quantity and quality of water resources, often leading to pollution from sewage discharge and industrial effluents Key factors affecting water resources include water demand for industrial and public use, reservoir construction, irrigation, flood control, and land development, which collectively contribute to alterations in water availability and quality in Vietnam.
STUDY AREA
Natural conditions
Chau Hanh commune's terrain is characterized by hills and streams, creating a diverse landscape The area features eight prominent streams originating from high mountains with steep slopes, including Ke Ninh stream in the north flowing westward into Hieu River, and Lan and Bong streams descending from Bu Xen Mountain (583m) towards the southwest-northeast direction Additionally, My and Minh Chau streams in the east originate from Tung Ca Mountain (625m) and Pu Nghin (435m), shaping the commune’s rugged terrain.
Chau Hanh commune is located in the North Central climate region of Nghe An, characterized by a tropical monsoon climate with hot and rainy weather The area receives approximately 1,580 to 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 occurs from August to October, bringing total annual rainfall of 1,700 to 2,000mm, 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, making it a crucial period for local people 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 boasts 11,428.8 hectares of forest land, representing 90.1% of its total area, with nearly half (5,207.8 hectares) designated as production forest Of this, 4,191 hectares of production forest are managed by families and individuals, highlighting the community's active involvement in sustainable forestry practices.
Industrial production in Chau Hanh commune is primarily driven by the availability of local raw materials, including sand for construction and building stone The area focuses on extractive industries such as sand mining and stone quarrying, supporting the local construction sector Additionally, woodworking and carpentry are important economic activities, utilizing locally sourced timber to meet regional demands These combined industries play a crucial role in the commune’s economic development, leveraging natural resources to sustain various industrial and craftsmanship sectors.
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 accurate sampling, use a clean 500ml bottle, ensuring it is thoroughly rinsed three times with local water before use Proper preparation includes gathering essential materials such as tapes, markers, paper labels, cockroach traps, and sealed barrel sponges Maintaining cleanliness and organization during sampling at any location is crucial for reliable results.
- Preserving and transporting of samples:
Water samples collected in bottles should be cooled to approximately 4°C and transported promptly to the laboratory On-site measurements of pH, temperature, and TDS should be conducted immediately to ensure accuracy Once collected, samples should be stored in a cool, dark place, as they typically remain stable for up to 24 hours, preserving their integrity for accurate testing.
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 the glass fiber filter disk, insert it onto the base and clamp it onto the funnel While applying vacuum, wash the disk with three successive 20 mL volumes of reagent water, ensuring all traces of water are removed by continuing vacuum drying after each wash Dry the filter in an oven at 103°C to 105°C for one hour in an aluminum dish, then remove, desiccate, and weigh the filter in the dish for accurate analysis.
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
To ensure accurate analysis, continuously stir the sample while sub-sampling and use a 100 ml graduated cylinder to quantitatively transfer it to the filter After the sample has passed through, remove all traces of water by applying vacuum until the sample is thoroughly dry.
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 very high BOD5 levels, which were appropriately diluted before testing to ensure accurate results The dilution water was saturated with oxygen through bubbling and contained essential nutrients to support microbial activity during the analysis.
To determine BOD₅, first dilute the sample and measure the initial dissolved oxygen (DO₀) at 20°C The sample is then incubated in a BOD bottle at 20°C for five days After incubation, the dissolved oxygen (DO₅) is measured again The BOD₅ value is calculated by subtracting the DO₅ of the sample from that of the blank sample, providing an indication of the organic matter present in the water.
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, where organic matter is oxidized using a boiling mixture of chromic and sulfuric acids During the procedure, a sample is refluxed in strongly acid conditions with an excess of potassium dichromate (K2Cr2O7), and the remaining unreduced dichromate is titrated with ferrous ammonium sulfate to measure the oxidized organic material in terms of oxygen equivalent To ensure accuracy, reagent ratios, including weights, volumes, and strengths, must be kept constant when using sample volumes other than 50 ml The standard 2-hour reflux time can be shortened if validated to produce equivalent results For samples with very low COD levels or heterogeneous solids, replicate analyses may be necessary to obtain 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 indicates that the dissolved oxygen (DO) levels in the Hieu River generally meet the A2 standard for domestic water quality However, after the river flows through Chau Hanh commune, the DO value decreases from 5.62 mg/L to 4.99 mg/L, suggesting a decline in water quality downstream.
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 study results indicate that the Hieu River has a low average TDS level of approximately 20.3 mg/L, well below the acceptable aesthetic threshold of 500 mg/L for human drinking water [9], and within the tolerance range of most aquatic ecosystems with mixed fish fauna, which can withstand TDS levels up to 1000 mg/L [10] Additionally, after the river flows into Chau Hanh commune, dissolved oxygen (DO) levels increase from 19.1 mg/L to 21.2 mg/L, suggesting improved water quality in the area.
Measured values of TSS in study area are shown in the following graph:
Figure 6.6 The analytical result of TSS
The study indicates that Hieu River in the designated area is critically polluted by suspended solids The total suspended solids (TSS) levels in Hieu River water in Chau Hanh commune are significantly elevated, highlighting severe water quality issues This high concentration of suspended solids poses environmental challenges and requires immediate attention to improve river health.
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 analysis reveals that the BOD5 and COD levels in Hieu River water in Chau Hanh commune exceed national water quality standards Specifically, BOD values are approximately 1.2 to 1.5 times higher than the B2 standard, with concentrations ranging from 29.2 to 38.8 mg/L Similarly, COD levels are also elevated beyond permissible limits, indicating significant water pollution in the area.
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
Hieu River water, after flowing into Chau Hanh commune, has experienced a worsening pollution trend Although current pollution levels are not critically high, the water quality has degraded to the point where it can only be used for irrigation purposes Consequently, this water source is unsuitable for domestic use, highlighting the need for ongoing monitoring and potential treatment solutions to protect community health and agriculture.
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 land cover density in the riparian buffer of Hieu River is lower compared to other areas in Chau Hanh commune, likely due to the proximity to the water source which favors production activities However, the loss of vegetation on either side of the river can lead to deteriorations in water quality, highlighting the importance of maintaining riparian buffer zones for environmental health.
From the collected documents and interview survey, the economic activities in Chau Hanh commune are:
Farmland occupies the majority of the riparian zone along the Hieu River in Chau Hanh commune According to interviews with local residents living near the river, their environmental awareness remains limited This highlights the need for increased educational efforts to promote sustainable land use and river conservation in the area.
Shifting cultivation is the primary farming method practiced by residents in this area, involving clearing forest land through slash-and-burn techniques to cultivate crops such as rice, cassava, and maize This practice leads to forest loss and increased soil erosion, which negatively impacts the ecosystem After harvest, farmers often burn remaining crop debris to naturally enhance soil nutrients, promoting microbial activity and faster land reclamation However, this agricultural approach can adversely affect water quality by releasing nutrients and chemicals like pesticides into water bodies through soil erosion and runoff, causing biological contamination from microorganisms present in manure and other soil-bound substances.
Interviews with residents of Chau Hanh commune living near the Hieu River reveal that most families own between 2 to 10 cattle, primarily fed through free grazing These cattle mainly graze along the riverbank, which negatively impacts the riparian vegetation buffer of the Hieu River This livestock grazing practice contributes to environmental degradation by damaging the natural vegetation in the river’s riparian zone.
Chau Hanh commune currently lacks an industrial zone, with only a few forest product processing facilities However, unchecked mining activities along both sides of the Hieu River have led to significant environmental issues, notably water pollution in the river In addition to deforestation for agriculture, these mining operations are a primary source of environmental degradation in the area.
TSS pollution in Hieu River, located in Chau Hanh commune, accounts for 25% of overall water contamination Additionally, mining activities significantly alter soil structure, increasing the risk of landslides and riverbank erosion, which threaten the local ecosystem and community safety.
Trade and service activities in Chau Hanh commune remain small-scale, with development investments lacking comprehensive planning Healthcare and transportation are the primary service sectors, currently having minimal environmental impact However, insufficient focus on waste collection and treatment in these industries could lead to significant environmental issues in the long term.
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 lands and roads show lower quality compared to those from forested areas, primarily due to higher land cover in forests that naturally protect water quality Heavy rainfall in Nghe An province during sampling intensified erosion, especially with reduced forest cover caused by farmland and road developments, leading to increased sediment and pollutants in the Hieu River Additionally, agricultural activities contribute directly to water pollution through the runoff of soil, nutrients, and pesticides during rainfall events, further degrading water quality.
Water samples collected near roads typically exhibit the lowest quality due to low plant cover density, which reduces natural filtration, and the direct impact of dust and waste from vehicles, which contaminate river water and degrade its overall 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 reduction of forest resources is a key factor contributing to water quality deterioration and water resource depletion in the Hieu River Current surveys indicate that the remaining forest area within the river's riparian buffer zone is critically small, emphasizing the need for effective reforestation strategies This article proposes solutions such as regenerating and protecting existing forests, nurturing and enriching forest areas, and implementing new planting initiatives to restore and expand forest coverage along the riparian buffer, ultimately improving water quality and ensuring sustainable water resources.
Regeneration and protection of existing forests is a sustainable reforestation strategy that utilizes natural regeneration processes, especially in favorable areas Effective measures include prohibiting grazing in regeneration zones, safeguarding forests by banning tree cutting in protected areas, and assigning management responsibilities to local communities, with regular monitoring to ensure compliance Fire prevention and firefighting measures are essential to protect the forests from potential threats Additionally, shifting cultivation practices among local residents pose a high risk to forest health; therefore, implementing strict policies against forest burning, alongside education and awareness campaigns, is crucial to promote the importance of forest conservation.
This is an in expensive solution but create high ecological benefit
Nurturing and enriching forests focuses on caring for woody plants that enhance land quality and promote ecosystem health This involves planting native tree species with strong regenerative abilities, such as Melia azedarach, Acacia auriculiformis, and Cinnamon (Cinnamomum cassia), to improve biodiversity and ensure sustainable forest development.
- 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 is designed to evaluate the impact of human activities on water conditions It assesses the suitability of water for various uses, ensuring its quality meets regulatory standards and supporting sustainable water resource management.
- 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 thesis findings indicate that the average flow discharge of Hieu River has been decreasing over time Water quality in Hieu River, located in Chau Hanh commune, does not meet environmental standards, with TSS, BOD, and COD levels exceeding the B2-QCVN standards Consequently, Hieu River water is unsuitable for domestic use and can only be utilized for irrigation purposes.
The study of economic activities' impacts on the water quality of Hieu River in Chau Hanh commune reveals that land use characteristics, particularly in the riparian buffer zone, significantly influence water quality Land types such as built-up areas (roads), farmland, and forest land have a notable adverse effect on water quality, contributing to deterioration Conversely, increasing plant cover in these areas can help improve water quality, highlighting the importance of sustainable land management and conservation efforts to maintain healthy river ecosystems.
The article proposes a range of solutions to enhance water quality and promote sustainable use in the study area, including policy measures, land use and planning strategies, and technical interventions Among these, increasing forest cover emerges as the most effective long-term solution for improving the water quality of Hieu River in Chau Hanh commune.
This study offers valuable scientific insights for optimizing land use and controlling water pollution in rural and mountainous areas of Vietnam It emphasizes the impacts of economic activities on water quality while acknowledging that factors like climate, precipitation, and population density also play significant roles These findings can aid policymakers in balancing water resource exploitation and protection to promote sustainable development.
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