<p>Vi&scaron;e od 100 vrsta virusa ljudi i životinja se izlučuje u spolja&scaron;nju sredinu. Prisustvo ovih virusa u povr&scaron;inskim vodama reflektuje fekalnu kontaminaciju i ukazuje na<br />opasnost za zdravlje ljudi i životinja. Na području Srbije se ne prati prisustvo patogenih virusa u povr&scaron;inskim vodama, pa&nbsp; čak ni u vodama za piće, a nije uspostavljena&nbsp; ni&nbsp; metodologija ovih ispitivanja. Shodno tome, cilj disertacije je da se utvrdi i analizira prisustvo animalnih i humanih virusa u povr&scaron;inskim vodama primenom najsavremenijih metoda koncentrovanja i detekcije virusa. U okviru disertacije ispitano je prisustvo sledećih virusa u povr&scaron;inskim vodama na teritoriji Vojvodine: humanih adenovirusa (HAdV); norovirusa (NoV) i hepatitis A virusa (HAV), adenovirusa svinja (PAdV),&nbsp; poliomavirusa goveda (BPyV) i hepatitis E virus (HEV).</p><p>Ispitano je ukupno 108 uzoraka povr&scaron;inskih i otpadnih voda koji su prikupljani od oktobra 2012. godine do juna 2014. godine. U radu su primenjene najsavremenije metode koncentrovanja i detekcije virusa u vodi, koje se u Srbiji nisu koristile za ovu namenu. Sprovedenim ispitivanjima dokazano je da su animalni i humani virusi prisutni u povr&scaron;inskim vodama na području Vojvodine. Najče&scaron;će detektovan&nbsp; virus u povr&scaron;inskim vodama je humani adenovirus (42,4%), a potom norovirusi GII i GI (40,4% i 15,2%), adenovirus svinja (11,1%), poliomavirus goveda (7,1%) i hepatitis E virus (3,0%). U ukupno 9 testiranih uzoraka gradske kanalizacione vode najče&scaron;će je detektovan HAdV (44,4%), NoV GII i GI&nbsp; (66,7% i 22,2%), BPyV je detektovan u samo jednom od 9 uzoraka, a niti u jednom nisu detektovani PAdV i HEV. Hepatitis A virus nije detektovan u uzorcima, a eksperimentalno je potvrđeno da su metode primenljive i za detekciju ovog virusa. Na osnovu rezultata prinosa procesne kontrole i utvrđenog prisustva virusa u uzorcima,&nbsp; zaključeno&nbsp; je da se ove metode mogu veoma uspe&scaron;no koristiti za detekciju virusne kontaminacije&nbsp; povr&scaron;inskih voda. Izvr&scaron;ena je igenotipizacija virusa iz odabranih uzoraka metodom sekvenciranja dela virusnog genoma. Indirektno je potvrđeno da su infekcije&nbsp;&nbsp; detektovanim virusima prisutne u populaciji životinja i ljudi. Prisustvo virusa u&nbsp;&nbsp; povr&scaron;inskim vodama i uzorcima gradske kanalizacije odražava infektivni status stanovni&scaron;tva, ali predstavlja i značajan rizik za zdravlje životinja i ljudi na području koje gravitira ispitanim vodama.&nbsp;</p> / <p>Over 100 types of pathogenic viruses are excreted in human and animal wastes. The presence of human and animal pathogenic enteric viruses in water environments reflects fecal contamination and indicates a risk to public health.&nbsp; Republic of Serbia does not implement surveillance for the presence of pathogenic human and animal viruses in surface waters and even in drinking water, neither is the established methodology of these studies in any institution in Serbia.&nbsp; Accordingly, the aim of the study was to determine and analyze the presence of human and animal viruses in surface water,&nbsp; using the latest methods&nbsp; of&nbsp; concentration and detection of the viruses.&nbsp; Within the dissertation examined the presence of the following viruses in surface waters in Vojvodina:&nbsp; Human adenoviruses&nbsp; (HAdV), noroviruses (NoV)&nbsp; and hepatitis A virus), Porcine adenovirus (PAdV) and Bovine polyomavirus (BPyV)&nbsp; and&nbsp; Hepatitis E virus (HEV).<br />A total of 108 samples of surface water and waste water were collected from October 2012 to June 2014. The paper are applied the most advanced methods and the concentration of virus detection in water, which in Serbia are not used for this purpose. The conducted tests have proven that the animal and human viruses present in surface waters in Vojvodina. The most commonly detected virus in surface water was human adenovirus (42.4%), followed by Norovirus GI&nbsp; and GII (40.4% and 15.2%),&nbsp; Porcine adenovirus&nbsp; (11,1%),&nbsp; Bovine polyomavirus&nbsp; (7.07%) and hepatitis E virus (3,0%).<br />In total of&nbsp; nine analysed sewage samples human adenovirus was detected in 44,4%&nbsp; of&nbsp; samples. The prevalence of norovirus GII and GI in sewage&nbsp; samples was&nbsp; 66,7%&nbsp; and 22,2%. Bovine&nbsp; polyomavirus was detected in one of nine samples while porcine adenovirus and hepatitis E virus were not detected in any of analyzed samples.&nbsp; Hepatitis A virus was not detected in samples, but&nbsp; it has been experimentally confirmed that the methods applicable for detection of the virus. Based on the results of process control and yield determined the presence of virus insamples, it was found that these methods can be successfully used to detect viral contamination of surface waters. Also, in these study was performed genotyping of viruses from selected samples by sequencing a part of the viral genome. Indirectly it is confirmed that the infection detected viruses present in a population of animals and humans. The presence of virus in samples of surface water and urban sewage reflects the infectious status of the population, but also constitutes a significant risk to the health of animals and people in the area that gravitates with tested waters.</p><p>&nbsp;</p>

Detta examensarbete består av en resiliensanalys av ett stadbyggnadsprojekt i området Ulleråker, straxsöder om Uppsalas stadskärna. Resiliensanalysen kan bidra med perspektiv till planeringen för att säkraUppsalas dricksvattenförsörjning då stadsbyggnadsprojektet, enligt programförslaget, är planerat attligga på känsliga delar av Uppsalas grundvattentäkt och därför riskerar att förorena grundvattnet.Området Ulleråker ligger inom zon för vattenskyddsområde. Resiliensanalysen har tidigare inte använts i stor utsträckning för planeringkontexten och metoden hardelvis kritiserats för brister i praktisk användbarhet. Examensarbetet ämnar därför till att fylla håletmellan teori och praktik och därför testa metoden på ett praktiskt planeringsfall (Ulleråker) och ommöjligt föreslå förbättringar för dess användbarhet. Dessutom ska examensarbetet bidra till denpraktiska fallstudien för Ulleråker där Sweco och Uppsala kommun får nya perspektiv kring vilkaaspekter som är relevant att inkludera i planeringen. Metoden följer Resilience Alliance praktikerns handbok ”Assessing Resilience in Social-EcologicalSystems: Workbook for Practitioners”, vilken används för att analysera systemet utifrån handbokensfem steg, inkluderat vägledande frågor. Det första steget fokuserade på att definiera systemgränser samtidentifiera huvudproblem. Det andra steget handlade om systemdynamik i form av den adaptiva cykelnoch önskvärda eller icke önskvärda systemlägen. Det tredje steget fokuserade på tvärvetenskapligasamverkansprocesser mellan andra system på högre och lägre nivåer. Det fjärde steget handlade omaktörssamverkan. Slutligen, i det femte steget, sammanfattades analysen och adaptiva lösningar försystemet diskuteras vilka kan användas för att bygga ett resilient system. Analysen avstadsbyggnadsprojektet Ulleråker gjordes utifrån tillgängligt underlag från planprocessen samtintervjuer av nyckelpersoner, och fokuserade på riskerna för grundvattentäkten och ytvattnet i Fyrisån. Slutsatserna från resiliensanalysen är att metoden är svår att använda i en komplex planeringkontextutifrån handbokens utformning och fokus på mindre komplexa system. Även om det finns vissabegränsningar i analysmetodens praktiska användbarhet finns det faktorer som kan bidra tillplaneringskontexten, t.ex. ett ökat systemtänkande (Ulleråker som system), risktänk kringtröskeleffekter (irreversibel förorening av grundvattentäkten) samt längre tidsperspektiv (framtidaosäkerheter). Modellen ball-in-the-basin med systemlägen är relevant för att förstå ett systems önskade,oönskade eller irreversibla förändring liksom den adaptiva cykeln för att systemet ständigt utvecklas.Dessutom är en viktig poäng med de tvärvetenskapliga interaktionerna att kunskapen från systemetsminne bör utnyttjas i större grad. Finns redan kunskapen inom kommunen bör det social-ekologiskasystemet mycket snabbare kunna återhämta sig och återgå till ett fungerande dricksvattensystem (högresystemnivå). Resiliensanalysen har också identifierat och diskuterat strategiska åtgärder, som skullekunna skapa ett mer resilient Ulleråker, bland annat i form av att öka samverkansprocesserna(governance) och att initiera förändring. Avslutningsvis är de viktigaste slutsatserna kopplade till de tre pelarna: Social-ekologiska system(systemtänk), komplexa adaptiva system (risker för tröskeleffekter och att utvecklingen inte alltså skerlinjärt och förutsägbar utan inkluderar stora osäkerheter) samt utveckling över skalor av tid och rum(långa tidsperspektiv, men också olika geografiska skalor). Eftersom det utifrån handbokens utformningkrävs kunskap kring resiliens från analysören och dessutom mycket tid och resurser som det sällan finnsgott om i planeringsprocessen bör dessa tre pelare, tillsammans med anpassningsbarhet,omställningsbarhet och specifik samt generell resiliens, implementeras i traditionell planering. / This master thesis contains of a resilience assessment of an urban development project in the area called Ulleråker, a bit south of the center of Uppsala city. The resilience assessment aims to give newperspectives for obtaining water security in Uppsala, since the program proposal affects sensitive areasof the groundwater aquifer of Uppsala and is posing risks of contaminating the ground water aquifer.The area of Ulleråker is highly sensitive and therefore secured by a water protection area. The resilience assessment has not earlier been used to a large extent in the urban planning context andthe method has earlier been criticized for lack of practical usefulness. The thesis aims to fill the gapbetween scientific studies of practical cases. The method is therefore used on a practical case (Ulleråker)and propose improvements connected to the usability. The thesis should also contribute to the case,Ulleråker, where Sweco and the municipality of Uppsala are given new perspectives of what should beimportant to consider in planning. The method is based on the Resilience Alliance’s workbook ”Assessing Resilience in Social-EcologicalSystems: Workbook for Practitioners”, which is used to analyze the system based in five steps, includingguiding questions. The first step of the workbook focused on defining the system and limiting the systemtogether with identifying main problems. The second step of the assessment focused on the systemdynamic exploring the adaptive cycle as well as desired and undesired system regimes. The third stagefocused on interactions between different hierarchical levels of time and scale. The fourth stage focusedon governance, and on how actors cooperate with decision-making. The last stage focused onsyntezeising the assessment findings and adaptive solutions for building resilience. The analysis ofUlleråker is based on already completed investigations and material from the planning process togetherwith interviews of main actors and is focused on risks connected to ground- and surface water. The conclusions are that the resilience assessment is hard to use in a planning context with theconformation of today. Even though there are difficulties, the assessment can contribute with factors asthe resilience thinking about social-ecological systems (Ulleråker as a system with social and ecologicalsystems interacting), risks of thresholds (contaminating the groundwater) and the longer timeperspective (future uncertainties), to the planning context. The model ball-in-the-basin with systemregimes are relevant to understand the systems desirable, undesirable or irreversible development andthe adaptive cycle for the constant development (adaptation and transformation) of the system. Anotherimportant aspect with the cross-scale interactions (between levels) are to a higher extent use the memoryof the system. If the knowledge already exists in the municipality, the social-ecological system wouldbe able to reorganize faster and return to a functional drinking water system (on higher level). Theresilience assessment has also identified strategic actions that possibly could create a more resilientUlleråker, by for example increase the governance and initiating change. In conclusion, the most important aspects of the assessment to bring in to the planning process are thethree aspects: Social-ecological system (resilience thinking), complex adaptive system (risks connectedto thresholds and non-linear development including uncertainties) and cross-scale interactionsdevelopment (long time perspectives and geographical scales). The conformation of the workbookrequires great knowledge about resilience from the assessor, and there are seldom enough time andresources available in the conventional process. The three aspects together with adaptability,transformability and specified and general resilience should be implemented in conventional planning.

Surface water hydrology is a deeply studied subject, yet there are barely any studies concerning surface water connectivity, neither micro- nor macro scale. With the explosive development of GIS over the past decade, tools for measuring and analysing rivers and lakes are inumerable. Light detection and ranging (LiDAR) has also seen tremendous improvements over the years. This study uses high resolution digital elevation models and georeferenced aereal photographs to carry out a detailed GIS-analysis of river-lake connectivity in three catchments in Västerbotten, Sweden: Bjurbäcken, Hjuksån and Gargån. Hjuksån is located beneath the highest coast line (HCL) wheras the other catchments are located above this line. A second pupose of the study is also to test if lake size varies above and below HCL. Lakes were digitized at 1:2000 scale and the rivers were digitized and categorized in Strahler stream order using tools in ArcGIS Pro. The data from the study was compared to data from the Swedish Meteorological and Hydrological Institute (SMHI), as well as data from international studies. The results show a surface water connection of 71,4% for Bjurbäcken, 62% for Hjuksån and 73,1% for Gargån. Comparing this data to data from SMHI results in a lowering of the surface water connection by 20 percentage points för Bjurbäcken, 30,3 for Hjuksån and 8,2 for Gargån. Lake size was tested between the catchments using an ANOVA, yielding a significant difference between Hjuksån and Bjurbäcken as well as Hjuksån and Gargån, backing up the hypothesis that HCL affects lake size.

<p>  </p> <p>The management of water resources in East Africa is inherently challenged by rainfall variability and the uneven spatial distribution of freshwater resources. In addition to these issues, meteorological and water data collection has been inconsistent over the past decades, and unclearly defined purposes or end goals for collected data have left many datasets ineffectively curated. In light of the data intensiveness of current modelling and planning methods, data scarcity and inaccessibility have become substantial impediments to informed decision-making. Among the outputs of this research are 1) a revised technique for evaluating bias correction performance on reanalysis data for use in regions where precipitation data is temporally discontinuous which can potentially be applied to other types of climate data as well, 2) a new methodology for quantifying qualitative information contained in legislation and official documents and websites for the assessment of relationships between documented meteorological and water data policies and resulting outcomes in terms of data availability and accessibility, and 3) a fresh look at data needs and the value data holds with respect to water resources decision-making and management in the region.</p>

In countries with harsh winter climates extensive winter road maintenance is necessary to achieve traffic accessibility and road safety. These measures have high economic and environmental costs as snow free roads and winter road maintenance in Sweden today is achieved by a combination of mechanical snow clearance and the spreading of salt to prevent ice formation. The salt ends up in the roadside environment and has negative effects on groundwater and vegetation. An alternative to traditional winter road maintenance to obtain non-skid winter roads is the use of hydronic pavement(HP) systems. Existing HP systems in Sweden are powered by district heating which limits the application to urban locations. The goal is to utilize renewable energy sources such as geoenergy which can be used in both rural and urban locations. This thesis suggests Hamnbacken in Visby as a pilot project for a full-scale application of the proposed HP system using surface water source heat.The weather related road surface conditions on Hamnbacken, and the potential of a renewable energysource have been examined in this study and the proposed location has been found favourable for a HP system. / Länder med övervägande kallt vinterklimat är halkbekämpning en nödvändighet för trafikens framkomlighet och säkerhet. Åtgärderna som vidtas för att få snö- och isfria vägar är kostsamma samt har en hög miljöpåverkan, ett vedertagligt exempel är plogning och saltning. Saltet hamnar i slutändan inom vägens omgivande områden och har en negativ påverkan på grundvatten och vegetation. En alternativ lösning till traditionell halkbekämpning är uppvärmda vägar för att uppnå ett halkfritt vinterväglag. Befintliga väguppvärmningssystem i Sverige försörjs av fjärrvärme vilket är en begräsning då tillgången till fjärrvärme finns i anslutning till tätorter. Målet är att utnyttja förnybara energikällor såsom geoenergi som är tillgänglig både i tätorter och på landsbygden. Det här examensarbetet undersöker Hamnbacken i Visby som ett pilotprojekt för en fullskalig implementering av väguppvärmningssystem där sjövärme används som energikälla. Denna studie har undersökt väderrelaterade vägförhållanden på Hamnbacken samt potentialen för användning av sjövärme. Den föreslagna platsens förutsättningar har visat sig vara gynnsamma i detta avseende.

In this research, five different coagulants were evaluated to determine their effectiveness at removing turbidity, color and dissolved organic carbon (DOC) from a surface water in Sarasota County, Florida. Bench-scale jar tests that simulated conventional coagulation, flocculation, and sedimentation processes were used. Iron-based coagulants (ferric chloride and ferric sulfate) and aluminum-based coagulants (aluminum sulfate, polyaluminum chloride (PACl) and aluminum chlorohydrate (ACH)) were used to treat a highly organic surface water supply (DOC ranging between 10 and 30 mg/L), known as the Cow Pen Slough, located within central Sarasota County, Florida. Isopleths depicting DOC and color removal efficiencies as a function of both pH and coagulant dose were developed and evaluated. Ferric chloride and ACH were observed to obtain the highest DOC (85% and 70%, respectively) and color (98% and 97%, respectively) removals at the lowest dose concentrations (120 mg/L and 100 mg/L, respectively). Ferric sulfate was effective at DOC removal but required a higher concentration of coagulant and was the least effective coagulant at removing color. The traditional iron-based coagulants and alum had low turbidity removals and they were often observed to add turbidity to the water. PACl and ACH had similar percent removals for color and turbidity achieving consistent percent removals of 95% and 45%, respectively, but PACl was less effective than ACH at removing organics. Sludge settling curves, dose-sludge production ratios, and settling velocities were determined at optimum DOC removal conditions for each coagulant. Ferric chloride was found to have the highest sludge settling rate but also produced the largest sludge quantities. Total trihalomethane formation potential (THMFP) was measured iv for the water treated with ferric chloride and ACH. As with DOC removal, ferric chloride yielded a higher percent reduction with respect to THMFP.

<p> The hydrological cycle is affected by land use variability. Land use spatial and temporal variability has the power to alter watershed runoff, water resource quantity and quality, ecosystems, and environmental sustainability. In recent decades, agriculture lands, pastures, plantations, and urban areas have increased, resulting in significant increases in energy, water, and fertilizer usage, as well as significant biodiversity losses. </p>

Hydrology and water quality are affected by land use and climate changes. Mississippi’s diverse agro–ecosystem comprises of a range of land use land cover (LULC) including agriculture, forest, wetlands, urban, and grasslands. The objectives of this study were to investigate the impacts of various factors such as Best Management Practices (BMPs), wetlands, LULC, and climate changes on water quality and quantity. The hydrologic and water quality responses to dynamic LULC input in Soil and Water Assessment Tool (SWAT) were evaluated. Results showed that agricultural and forest expansion were major drivers of hydrologic and water quality changes in Big Sunflower River Watershed (BSRW), with agricultural expansion increasing runoff, sediments, and nutrients and forest expansion reducing these variables. The results showed that the integration of dynamic LULC and agricultural management operations in SWAT enables a more realistic representation of agricultural watersheds. Similarly, this study investigated the effects of wetland area changes overtime on surface and groundwater. Results demonstrated that 26% increase in wetland areas, reduced streamflow, sediments, total nitrogen, and total phosphorus by 2%, 37%, 13%, and 4% respectively as well as increased groundwater storage by 90 mm in selected sub–watershed. This highlighted the importance of preservation and restoration of wetlands to enhance the agro–ecosystem resilience to LULC change. Likewise, the effectiveness of BMPs in reducing sediment yield from critical areas within BSRW was assessed. Results demonstrated that BMPs reduced sediments by up to 50%, suggesting their usefulness in mitigating high sediment yield from agricultural areas. This study also assessed the impacts of climate change on streamflow and sediment loads and the role of waterbodies in mitigating those impacts. Results depicted a significant increase in future streamflow and sediment loads due to potential increase in precipitation and temperature. When waterbodies were simulated, projected change in annual streamflow was < 1%. However, the projected annual sediment loads reduced substantially by 44–46%, highlighting the role of waterbodies on watershed resilience to climate change. Overall, this dissertation study provides insights about the complex interactions between LULC, climate, anthropogenic activities, and water resources that can help to develop watershed management strategies to promote agricultural sustainability.

Climate change has been affecting to livelihoods of communities in the coastal plain of the Vietnamese Mekong Delta (VMD). Surface water management in the coastal plain was considered to be limited, especially in enforcement. Therefore, the research aimed to assess the stakeholder involvement, identify the conflict in using the surface water and mechanism to solve and avoid the conflict. The directive interview farmers and governmental staffs was implemented to collect the necessary data. The descriptive statistic was applied in order to analyze the collecting data through farmer survey. The questionnaire was built based on the governance assessment framework “Ten-building Block”. The results showed that the governmental group (including the people committee and the Provincial department) was the highest participatory in the management process both in decision-making level and interested level. The surface water users, especially the farmers participated with the average rate because of their low capacity in making the decision for a new policy or a new agricultural model. Besides, different groups of stakeholders as the non-governmental organization and governmental organization (the local Youth Union, Famer’s and Women’s Association) played an important role in raising the water user’s awareness. The remaining group, including nonagricultural company or traders, nearly were not concerned about the surface water changes. In addition, there were two main types of conflicts identified: between the farmers in the same kind (1) and different kind (2) of cultivation. As the consequence of the natural salinity and the impacts of output water from shrimp pond to the rice cultivation zone, the conflict was about the inefficient water regulation and distribution for each water user. These conflicts were mostly solved through self-negotiating and self-engaging between the farmers. In fact, there was no rule or principle to solve and prevent the potential water use conflict. Thus, this could be a great challenge for the surface water management in the agricultural zone as Soc Trang in the context of increasing the extreme climatic phenomenon. / Biến đổi khí hậu đã và đang tác động lớn đến sinh kế của các cộng đồng ven biển đồng bằng sông Cứu Long (ĐBSCL). Công tác quản lý tổng hợp tài nguyên nước mặt tại vùng ven biển được cho rằng còn tồn tại nhiều hạn chế, nhất là trong triển khai và thực thi. Vì vậy, nghiên cứu được thực hiện tại Sóc Trăng (một tỉnh ven biển ĐBSCL) nhằm đánh giá sự tham gia của các thành phần có liên quan, xác định các mâu thuẫn trong sử dụng nguồn nước mặt cũng như các giải pháp giải quyết và phòng tránh mâu thuẫn. Phương pháp phỏng vấn trực tiếp nông hộ, tham vấn chuyên gia quản lý và thống kê mô tả được áp dụng để đánh giá các mục tiêu đặt ra của đề tài. Các thông tin khảo sát được xây dựng dựa trên bộ mười tiêu chí đánh giá quản trị tài nguyên nước (van Rijswick et al., 2014). Kết quả cho thấy nhóm chính quyền địa phương (bao gồm UBND và các Sở/Ngành) có vai trò và mức độ tham gia cao nhất trong chu trình quản lý. Người sử dụng nước mặt, nhất là nông dân đóng góp sự tham gia tương đối do mức đô ra quyết định về thiết lập chính sách và lựa chọn mô hình canh tác thấp. Mặt khác, các nhóm đối tượng khác như các tổ chức phi chính phủ, Đoàn thể, Hội nông dân và Hội phụ nữ đóng góp vai trò quan trọng trong nâng cao nhận thức và kêu gọi cộng đồng sử dụng hiệu quả nguồn nước mặt. Các nhóm tổ chức kinh tế như doanh nghiệp, tiểu thương gần như không quan tâm đến nguồn nước mặt. Bên cạnh đó, các mâu thuấn về sử dụng nước mặt cũng được xác định. Các mâu thuẫn được phân chia thành 2 nhóm: cùng loại hình canh tác và giữa các loại hình canh tác khác nhau. Các mâu thuẫn chủ yếu về vấn đề điều tiết nguồn nước không hợp lý và thiếu cân bằng trong phân phối nước ngọt cho các đơn vị canh tác do xâm nhập mặn tự nhiên, xả thải nước mặn vào vùng ngọt và khai thác không đồng đều. Các mâu thuẫn này chủ yếu được giải quyết thông qua thương lượng và thỏa thuân giữa các đối tượng có liên quan chứ chưa có bất kỳ một cơ chế hay quy định nào nhằm giải quyết cũng như phòng tránh các mâu thuẫn tiềm tàng. Vì vậy, đây sẽ là một thách thức lớn cho công tác quản lý nguồn nước mặt tại vùng sản xuất nông nghiệp thâm canh như Sóc Trăng trong bối cảnh gia tăng cực đoan khí hậu.

The present study evaluates the surface water quality in the canals of An Giang province in the period from 2009 to 2016. The results showed that surface water of the canals was contaminated by organic matter and microorganisms which makes it not suitable for water supply and conservation of aquatic life. The water quality parameters such as dissolved oxygen (DO), biological oxygen demand (BOD), total suspended solids (TSS), orthophosphate (P-PO43-) and coliforms levels in the wet season were found to be higher than those in the dry season. The problem of organic and microorganic pollution over a long period of time without solutions leads to declines in water quality and then quantity as well. Agriculture is the main activity contributing to pollution of surface water in interior canals along with the activities of daily life, industry and services. This causes pollution of the surface water on Hau River due to its exchange of water with the connected canals. Good agricultural practices should be implemented to limit the pollution of surface water resources of the Mekong Delta. / Nghiên cứu này nhằm đánh giá diễn biến chất lượng nước mặt trong các kênh rạch nội đồng của tỉnh An Giang trong giai đoạn 2009 – 2016. Kết quả cho thấy nước mặt tại các kênh rạch nội đồng đã ô nhiễm hữu cơ và vi sinh vật. Nguồn nước không phù hợp cho mục đích cấp nước sinh hoạt và bảo tồn thực vật thủy sinh. Các chỉ tiêu như hàm lượng oxy hòa tan (DO), nhu cầu oxy sinh hóa (BOD), tổng chất rắn lơ lửng (TSS), orthophosphate (P-PO43-) và coliforms trong mùa mưa cao hơn mùa khô. Vấn đề ô nhiễm hữu cơ và vi sinh vật diễn ra trong thời gian dài và chưa có giải pháp xử lý làm cho chất lượng nước suy giảm dẫn đến suy giảm về trữ lượng. Nông nghiệp là hoạt động chính góp phần làm ô nhiễm nguồn nước mặt trong các kênh rạch nội đồng bên cạnh các hoạt động sinh hoạt, công nghiệp và dịch vụ. Điều này dẫn đến nước mặt trên sông Hậu cũng có đặt tính ô nhiễm tương tự do trao đổi nước với các kênh rạch nội đồng. Thực hành sản xuất nông nghiệp thân thiện môi trường cần sớm được triển khai để hạn chế ô nhiễm nguồn nước mặt quan trọng của khu vực đồng bằng sông Cửu Long.