This study presents a comprehensive analysis of plastic waste accumulation in both terrestrial and aquatic environments Can Tho city, Vietnam, nation with high per capita consumption significant discharge. Focusing on urban residential areas, riverside communities, suburbs, rural regions, the research investigates extent impact these diverse settings. Additionally, examines plastics at barriers, under bridges, Hau River, identifying predominance single-use their environmental implications....

Abstract Climate and rainfall are extremely non-linear complicated phenomena, which require numerical modelling to simulate for accurate prediction. We obtained local historical data 12 meteorological stations in the Vietnamese Mekong Delta (VMD) 45-year period 1978–2022, predict annual trends. A statistical time series predicting technique was used based on autoregressive integrated moving average (ARIMA) model. utilized seasonal ARIMA process of form (p,1,q)(P,1,Q) our study area. The best...

Globally, hydrometeorological hazards have large impacts to agriculture output, as well human well-being. With climate change derived increasing frequency of extreme weather conditions, the situation has becoming more severe. This study strives evaluate both dry and wet conditions in Vietnamese Mekong Delta (VMD), also known rice basket Southeast Asian region. Different meteorological parameters from last three decades were used develop drought indices for Ca Mau province investigate their...

The dynamic shifts in shorelines due to erosion and deposition have become a significant challenge coastal zone management, particularly the context of climate change rising sea levels. This paper evaluates shoreline protection efficiency various wave-reducing breakwaters Vietnamese Mekong Delta. delta exemplifies issue faced by deltas worldwide. Landsat satellite images were used establish development map for period 2000 2022. wave data front behind analyzed assess reduction breakwater...

Abstract This paper examines the impact of dike systems on river flows in Vietnamese Mekong Delta (VMD). The study combined a hydrological change index method and Mann–Kendall test to assess temporal dynamics both discharge water levels along main rivers VMD. Results highlight that system canals helps facilitate waterway traffic drainage during flood season. However, low elevation delta has created conditions suitable for saline increasingly penetrate upstream dry Observed changes indicators...

Duy, D.V.; Tanaka, H.; Mitobe, Y.; Anh, N.Q.D., and Viet, N.T., 2018. Sand spit elongation sediment balance at Cua Lo Inlet in Central Vietnam. In: Almar, R.; Almeida, L.P.; Trung N., Sall, M. (eds.), Tropical Coastal Estuarine Dynamics. Journal of Research, Special Issue No. 81, pp. 32–39. Coconut Creek (Florida), ISSN 0749-0208.Erosion is significant on the downdrift beach Inlet, which located The Inlet's updrift sand together with severe erosion bank raising numerous social problems such...

Tidal inlets with attached sand spits are a very common coastal morphology. Since the evolution of along coastline have greatly affected on social-economic development local areas. However, previous studies mainly focused which usually in scales hundred meters width. Therefore, this study, morphological change smaller and unexplored spit located west coast Phu Quoc Island, will be investigated. It was found that there is seasonal variation at Song Tranh Inlet. The Longshore sediment...

Abstract The Mekong Delta, South East Asia's ‘rice bowl’, sustains more than 18 million people through its agricultural output. This yield is secured by efficient water management systems but susceptible to climatic changes. As Vietnam's policies aim optimize the delta's semi‐mountainous regions reliant on rain‐fed agriculture, this study investigates drought risks and climate change impacts runoff in O Ta Soc Tuk Sa reservoirs, An Giang Province, Vietnam. Using simulation models, we...

ベトナム南部ロックアン河口において沿岸漂砂の下手方向への砂嘴の延伸が著しい.このため,河口右岸においては流路の移動に伴う深刻な侵食が見られる.しかし,当地ではこれまで様々な現地資料の蓄積が行われておらず,砂嘴延伸の状況・対策を論ずるための基礎資料が乏しい.そこで,1988年以降に撮影されているLandsat画像やGoogle Earth画像をもとにロックアン河口砂嘴の変動特性に関する検討を行った.その結果,砂嘴先端部は平均的に95m/年の速度で延伸し,一方,対岸の汀線位置もほぼ同じ速度で後退することから,一定の河口幅が維持されていることが分かった.また,この砂嘴移動速度に砂の移動高さを乗じることにより推定される沿岸漂砂量は,これまで数値シミュレーションにより評価された値と良好な一致を示した.

Tidal inlets with attached sand spits are a very common coastal landform. Since the evolution of along coastlines influence social-economic development local areas, have become objects numerous studies. However, previous studies mainly focused on that usually in scale hundreds meters width, whilst knowledge about smaller-scale still remains limited. Therefore, this study, morphological change small and unexplored spit front Song Tranh Inlet west coast Phu Quoc Island, Vietnam is...

Coastal erosion is threatening the infrastructures of coastal community at Ma River mouth in Thanh Hoa province, Vietnam. When happens, people try to prevent it by emergency solutions like hard structures. However, this approach usually leads more severe problem since mechanism for not investigated and understood properly. In study long-term configuration Province, Central Vietnam has been using Landsat imagery from 1987 2023. An analytical solution one-line model shoreline change was also...

Morphology of Cua Dai River mouth and adjacent sandy beaches in Hoi An City, central Vietnam has been being eroded severely recent years. Results Landsat image analysis reveal that morphology river the period from 1975 to 1991 is highly similar one 2003 2015; long sand spit on left side cuspate shoreline (cuspate foreland) right side. Meanwhile, welding two occurred 1995 2002. The topography formed during 40-year are classified into three types. bank shifted south about 250m. That...

Analytical solutions for a one-line model shoreline changes are employed to investigate the formation of two wave-dominated river delta coastlines, along with small-scale laboratory experiment. Since present analytical solution can be applied only infinite shorelines, new was developed consider effects lateral boundaries evolution coastlines. It determined that demarcations represented by dimensionless times t* used judge whether have affected coastline or not. After successful application...

Can Tho City is located in the middle of Mekong Delta, where effects climate change have been and will continue to be considerable. According predictions, city one five regions that could affected. In this study, we conducted analysis trends T max min over 39 years using monthly temperature City. We employed a Box plot, Mann–Kendall test, Sequential Trend Analysis (SMK). increased for all 12 months from 1984 2022, with Sen’s slopes 0.45°C/decade 0.29°C/decade, respectively. Although shows...

クアダイ海岸はベトナム中部クアダイ河口の左岸に位置するビーチリゾートである．しかし，近年クアダイ海岸における河口周辺部の侵食が著しく，現地の観光産業にも影響を与えつつある．これまで，Google Earth画像や衛星画像を用いた侵食の状況に関する検討がなされている．しかし，現地においては使用出来る現地資料が十分ではないことから，評価の精緻化に困難を伴っていた．そこで，まず，現地においてビデオカメラ撮影を設置して継続的なモニタリングを行い，比較的短期間における侵食の進展状況を明らかにした．さらに，これまで実施されている衛星解析範囲に比べて広域の海浜を対象とし，全域で75kmにわたる砂浜の変化傾向を明らかにし，さらに河川からの供給土砂量を考慮することにより，クアダイ河口から周辺海浜を含む領域での土砂収支評価を実施した．

Google Earth画像はここ10年程度の期間における汀線変動を知る際にはきわめて有効であり，これまでも多くの海浜変形に関する研究において使用されている．ただし，撮影時刻が示されていないことから，汀線判読にあたって潮位補正を行うことが出来ないという大きな欠点を伴っていた．そこで，晴天時に撮影された画像には建物など背の高い物体の影が写っていることが多いことから，この情報を活用して撮影時刻を推定する手法を提案した．まず，長期にわたり撮影画像が蓄積されている仙台海岸を対象に同手法を適用し，既知の撮影時刻との比較により，推定時刻の誤差が最大でも7分ほどであることを明らかにした．その後にGoogle Earth画像への応用を試み，この補正の有無が中期的な汀線の後退・前進の判断に及ぼす影響を検討した．

Nghiên cứu nhằm mục đích chế tạo và thử nghiệm lớp phủ bảo vệ cho vải địa kỹ thuật (ĐKT) polyester để tăng độ bền môi trường, ứng dụng xây dựng kè mềm giảm sóng bờ biển. Lớp được từ hỗn hợp fluoropolyme/bitum/dầu hạt điều, phụ gia kháng UV một số loại khác. đáp tốt các yêu cầu về khả năng bám dính, tính chất cơ lý trường ĐKT polyester. Tính xác định bằng phương pháp đo kéo đứt. hoá của thông qua phân tích TGA/DSC, FTIR. Độ QUV test 2000 giờ với chu kỳ 4 chiếu phun sương. đã thiết lập đơn pha...

Beach erosion and coastal protection are complex interconnected phenomena that have a substantial impact on environments worldwide. Among the various measures, seawalls been widely implemented to mitigate protect assets. However, interrelationship between beach remains critical topic for investigation ensure effective sustainable management strategies. Seawalls shoreline, particularly through “end effect”, where seawall functions similarly groin, causing downdrift side relative direction of...

Mục tiêu của nghiên cứu này là quan trắc diễn biến đường bờ sông và biển Cù Lao Dung bằng công nghệ phân tích ảnh viễn thám giai đoạn 2008-2022. Ảnh đa phổ Landsat được sử dụng để loại chiết xuất bờ. Các kết quả cho thấy từ năm 2008 đến 2022, tổng diện tăng 309 ha, giảm 78 tại vị trí xói lở nghiêm trọng nhất có lùi sâu 61 m vào đất liền tốc độ bồi tụ lớn nhất, đã mở rộng thêm khoảng 650 m.

Coastal erosion poses a significant threat to the infrastructure of coastal community at mouth Ma River in Thanh Hoa Province, Vietnam. In response, emergency solutions such as hard, protective structures are often implemented. However, this approach exacerbates problem underlying mechanisms not adequately investigated and understood. study, long-term configuration Central Vietnam, is using Landsat imagery spanning from 1987 2023. An analytical solution one-line model for shoreline change...

The objective of this study is to assess the shoreline changes and wave reduction effectiveness detached breakwaters constructed along West coast Ca Mau province.First, satellite images including Landsat downloaded by Google earth tool (Google images) were processed monitor temporal positions.Waves in front behind measured analyzed different types breakwaters.The image analysis results show that area protection forest has been reduced seriously (about 160 ha) last 20 years at rate 8.18 7.76...

近年，各地の河口部において深刻な侵食現象が見られる．このような河口デルタの発達と汀線後退を論ずる際，線形近似された拡散方程式型のワンラインモデルの解析解を使用することがある．ただし，通常使用される解析解は無限長の砂浜に注ぐ河川を対象としている．このため，実際に存在する岬などの砂浜端部の影響を加味することが出来ない．そこで，有限長さの砂浜に発達する河口デルタに関する理論的検討を行った．その結果，無次元時刻t*が0.3よりも短い時間の間では境界の影響が現れず，既往の解が適用できることが分かった．また，無次元時刻がこの限界時間より大きい時には放物線形状の汀線が平行移動する単純なデルタ発達過程を示しており，この時，河口から境界にかけて漂砂量は直線的に減少する．実験値を用いてこの理論の検証を行った．

河口部周辺における海浜の侵食問題は国の内外を問わず大きな課題である．そこで，本論文においては，(1) 河川流出土砂の増減，ならびに(2) 河口開口部の移動による河口デルタ地形の変化について解析的な検討を行った．解はワンラインモデルを基本とし，無限長の砂浜を対象とする基本解の線形重ね合わせにより二つの条件に対する解析解を導いた．これにより，河口デルタの侵食・回復過程を容易に予測することが可能となった．また，一般に砂浜端部には岬や人口構造物などの端部境界が存在することから，(1)のケースについて，すでに著者らにより得られている有限長砂浜でのデルタ発達過程に対する解の重ね合わせにより，デルタ変形過程に関する解を得た．侵食波の端部への到達以降，先述の無限域での解と比べて大きな差異を示すことが判明した．

ベトナム中部のツーボン川河口左岸に位置するクアダイ海岸においては近年海岸侵食が著しい．クアダイ河口周辺の汀線は海側に突出した典型的なデルタ地形を有している．そこで，デルタ形状に対するワンラインモデルの解析解の無次元表示をもとに，モデル定数を定める手法を示した．また，モデルより，河口部左右岸における汀線勾配をもとに河川供給土砂量を推定する手法を得た．この手法の妥当性を検討するために，まず，本手法を他の河川や，条件が制御された水理実験に適用したところ，比較的良好な一致を示すことを確認した．また，同手法により推定されたクアダイ河口の供給土砂量は，他の報告にある推定値とオーダー的に近いものであった．本推定によると，2000年以降，河川からの供給土砂にわずかな減少が見られた．