Literatura científica selecionada sobre o tema "Water Pollution Vietnam"

Phytoremediation has been intensively studied during the past decade due to its cost-effectiveness and environmental harmonies. Most of the studies on treatment of heavy metal pollution in soil and water by plant species have been done in developed countries but are limited in Vietnam. In this study, we presented some research results of phytoremediation of polluted soils and water with heavy metals that were done by Institute of Environmental Technology for several last years. For treatment of heavy metal pollution in the water, some plants have great ability to accumulate heavy metals such as Vetiveria zizanioides, Phragmites australis, Eichhornia crassipes, Pistia stratiotes, Ipomoea aquatica, Nypa fruticans and Enhydra fluctuans. The heavy metal uptake into shoots and roots of 33 indigenous plant species in Thai Nguyen province was also determined. Two species of the plants investigated, Pteris vittata L. and Pityrogramma calomelanos L. were As hyperaccumulators, containing more than 0.1% As in their shoots while Eleusine indica, Cynodon dactylon, Cyperus rotundus and Equisetum ramosissimum accumulated very high Pb (0.15-0.65%) and Zn (0.22-1.56%) concentrations in their roots. Some experiments to clarify the potential of several plants as good candidates for phytoremediation of polluted soil by heavy metals were carried out in our institute.<br>Phương pháp sử dụng thực vật để xử lý ô nhiễm đã được nghiên cứu nhiều trong thập kỷ qua do chi phí thấp và thân thiện với môi trường. Hầu hết các nghiên cứu về xử lý ô nhiễm kim loại nặng trong đất và nước bằng thực vật đã được thực hiện ở các nước phát triển nhưng ít có tại Việt Nam. Trong nghiên cứu này, chúng tôi giới thiệu một số kết quả dùng công nghệ thực vật để xử lý ô nhiễm kim loại nặng trong đất và nước tại Viện Công nghệ môi trường trong những năm gần đây. Dối với xử lý ô nhiễm kim loại nặng trong nước, một số thực vật có khả năng tích lũy tốt kim loại nặng như Vetiveria zizanioides, Phragmites australis, Eichhornia crassipes, Pistia stratiotes, Ipomoea aquatica, Nypa fruticans và Enhydra fluctuans. Sự hấp thụ và tích lũy kim loại nặng trong phần trên mặt đất và rễ của 33 loài thực vật bản địa tại Thái Nguyên cũng đã được xác định. Hai loài thực vật khảo sát là Pteris vittata và Pityrogramma calomelanos là những loài siêu tích lũy As, chứa hơn 0,1% As trong phần trên mặt đất của cây. leusine indica, Cynodon dactylon, Cyperus rotundus và Equisetum ramosissimum tích lũy Pb (0,15-0,65%) và Zn (0,22-1,56%) rất cao trong rễ. Một số thí nghiệm đánh giá tiềm năng của một số thực vật là đối tượng tốt cho xử lý ô nhiễm kim loại nặng trong đất đã được tiến hành trong phòng thí nghiệm của Viện Công nghệ môi trường.

Lakes in Hanoi play an important role in local human life. However, along with the economic and social development, some urban lakes have been polluted, especially organic pollution. This paper presents the monthly survey results for organic pollution assessment of ten selected lakes in Ha Noi city: the Ho Tay, Truc Bach, Thien Quang, Ba Mau, Bay Mau, Hoan Kiem, Ngoc Khanh, Giang Vo, Thanh Cong and Thu Le lakes during the period from March 2014 to February 2015. The survey results showed that the Ba Mau lake was organic polluted at level IV whereas other lakes were contaminated by organic matters at level III. Organic pollution may come from both autochthonous and allochthonous sources. Compared with the results of previous studies, the water quality of 10 lakes in the period from March 2014 to February 2015 has been improved thank for the recent application of some positive solutions for lake environmental protection.<br>Hệ thống hồ ở Hà Nội đóng vai trò quan trọng trong đời sống của người dân. Tuy nhiên, cùng với sự phát triển kinh tế xã hội, nhiều hồ trong nội đô đã và đang bị ô nhiễm, đặc biệt là ô nhiễm hữu cơ. Bài báo này trình bày kết quả khảo sát ô nhiễm hữu cơ tại 10 hồ trong thành phố Hà Nội: hồ Tây, Trúc Bạch, Thiền Quang, Ba Mẫu, Bảy Mẫu, Hoàn Kiếm, Ngọc Khánh, Giảng Võ, Thành Công và Thủ Lệ trong thời gian từ tháng 3 năm 2014 đến tháng 2 năm 2015. Kết quả khảo sát cho thấy hồ Ba Mẫu bị ô nhiễm hữu cơ ở mức IV, các hồ còn lại bị ô nhiễm hữu cơ ở mức III. Ô nhiễm hữu cơ tại các hồ có thể do cả hai nguồn cung cấp chất hữu cơ, ngoại lai và nội sinh. So với kết quả quan trắc trước đây, chất lượng nước 10 hồ Hà Nội đã được cải thiện do gần đây đã áp dụng một số biện pháp bảo vệ môi trường cho các hồ.

Due to utilization increase of chemical fertilizers and manures and of a large water volume for irrigation, agricultural runoff has significantly accelerated water pollution. The Red River locates in Vietnam where agriculture plays an important role in the country’s economy. This paper presented the observation results of organic matters concentrations in agricultural runoff from different plant fields (vegetable, flower and rice) in the Red River Delta in 2013 -2014. The results showed that DOC concentrations varied in a high range from 1.0 mg.L-1 to 37.1 mg.L-1, averaging 10.2 ± 6.2 mg.L-1 whereas POC concentrations varied from 0.5 to 4.5 mg.L-1, averaging 1.7 ± 0.7 mg.L-1 for a total 104 samples observed. TOC concentrations in water from the vegetable and flower fields (11.7 ± 7.3 mg.L-1 and 12.6 ± 6.0 mg.L-1 respectively) were higher than the one from the rice field (8.5 ± 6.6 mg.L-1). Lower organic matters concentrations were found in the rainy season than in the dry season due to dilution process. The results suggest the needs for regularly monitoring and efforts to control organic matter pollution from agricultural runoff in the Red River basin or other river basins in developing countries.<br>Do sử dụng phân bón và thể tích nước tưới lớn, canh tác nông nghiệp đã và đang góp phần đáng kể gây ô nhiễm nguồn nước. Sông Hồng nằm ở Việt Nam, nơi ngành nông nghiệp đóng vai trò quan trọng trong nền kinh tế. Bài báo trình bày kết quả quan trắc hàm lượng cacbon hữu cơ (TOC) bao gồm dạng hòa tan (DOC) và không tan (POC), trong nước chảy tràn từ đất canh tác (rau, hoa, lúa) ở đồng bằng sông Hồng năm 2013 -2014. Kết quả cho thấy DOC thay đổi rất rộng từ 1,0 mg.L-1 đến 37,1 mg.L-1, trung bình đạt 10,2 ± 6,2 mg.L-1 trong khi POC thay đổi từ 0,5 mg. L-1 đến 4,5 mg.L-1, trung bình đạt 1,7 ± 0,7 mg.L-1 đối với 104 mẫu nước. TOC từ trồng rau và hoa (11,7 ± 7,3 mg. L-1 và 12,6 ± 6,0 mg.L-1) cao hơn so với trồng lúa (8,5 ± 6,6 mg. L-1). TOC trong mùa mưa thấp hơn so với mùa khô. Cần thường xuyên giám sát và nỗ lực kiểm soát ô nhiễm chất hữu cơ do nước chảy tràn từ đất canh tác ở lưu vực sông Hồng.

Encompassing both urban and rural processes, the peri-urban interface (PUI) provides a unique and challenging arena for environmental management. As the urban core expands, the PUI industrializes and urbanizes, undergoing rapid social, economic, and environmental changes. One of the results of this transformation is often an increase in pollutants and environmental degradation. In the twenty years since the initiation of its reforms towards a more market-oriented economy, Vietnam has seen significant growth, much of this occurring within the industrial sector in and around urban hubs such as Ho Chi Minh City (HCMC). Rapid urbanization and industrialization has occurred with limited control, and a trend has emerged where industrial activity has moved out of the urban core and into the PUI. Despite ongoing efforts, the government of Vietnam, as in other Asian countries, is unable to fully regulate firms illegally releasing untreated and often highly polluted wastewater. The result is that farmers in HCMC’s PUI must now contend with lower crop yields or even failures – and food safety concerns due to an influx of pollutants in irrigation waters. Combining a rights-based approach and a good governance approach, this research describes the constraints on both farmers and government officials that prevent a resolution of farmers’ pollution problems. These constraints are argued to stem from systemic water governance issues in Ho Chi Minh City and Vietnam. They include poor communication between farmers and government officials, limited farmer participation in water management, a lack of integration between government agencies, little government accountability and transparency, and water management priorities that favour economic growth over environmental health. It is argued that strengthening farmers’ water rights could address these issues. However using a rights based approach would first require addressing gender inequities in community affairs, institutional changes to ensure the recognition of farmers’ rights in practice, compensating those harmed by pollution, and educating farmers on the legal system and the water rights it provides. In addition to addressing a general lack of literature on water governance in Vietnam, this research has implications for literature regarding peri-urban environmental management, good water governance, and the rights based approach. This research suggests that the challenges present in the PUI exacerbate and thus illuminate poor water governance practices that extend beyond the local scale. It also suggests that water rights be used as a possible platform to achieve good water governance. Lastly, it explores the potential challenges of implementing a rights based approach.

Research Doctorate - Doctor of Philosophy (PhD)<br>Shrimp farming and capture fishery are two of the major industries of Can Gio district, Ho Chi Minh City, southern Vietnam. These industries have recently developed and contributed to the improvement of local economy. However, they have also raised environmental concerns regarding water pollution and fish stock depletion. The negative impacts of shrimp farm effluents on the water quality of mainstream rivers and fish communities have not been studied in Can Gio. Additionally, there is a lack of research on the influence of the current fisheries management on environmental protection and fish conservation in this district. The goal of this study was to address key issues in fisheries management in Can Gio in regard to the impacts of wastewater from shrimp farming on the water quality of mainstream rivers that affect the local fish communities, and the influence of improper fishing practices that lead to the depletion of local fish stocks. This study also aimed to propose strategies to improve the local fisheries management for more environmentally responsible productions. Two mainstream surveys were developed to obtain data, i.e. environmental surveys for the assessment of water quality and pollution impacts on fish communities; and people interviews for the examination of fisheries management related to shrimp farming and fishing practices. The findings were used as a baseline to develop appropriate strategies for improving the management in terms of promoting sustainable productions both in shrimp farming and capture fishery industries and protecting the environment. This study found that shrimp farming, especially intensive farms have contributed to water pollution in mainstream rivers in Can Gio, and in turn the water pollution has adversely affected the local fish communities. The waters adjacent to the intensive farms were contaminated with high concentrations of organic matter. The number of fish species reduced and tolerant species appeared at higher proportions in these areas. Many improper practices in shrimp farming and fishing as well as weaknesses in government management were addressed to be the key issues leading to environmental pollution and fish depletion. The proposed strategies focused on improving the management at both government and community levels. Promoting community-based management was suggested as a key to the success in fisheries management in Can Gio.