A survey of parabens in aquatic environments in Hanoi,Vietnam and its implications for human exposure and ecological risk

Environmental Science and Pollution Research - Seven parabens including methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), iso-propylparaben (iPrP), butylparaben (BuP), benzylparaben...     

Process modeling and economic assessment of converting municipal solid waste into solid fuel via hydrothermal processing: a case study in Vietnam

Journal of Material Cycles and Waste Management - As with any developing country, Vietnam has faced numerous challenges in the management and treatment of municipal solid waste (MSW)....     

人口迁徙、汇款、生活轨迹及社会应变能力

我们认为,人口变化的方方面面,包括迁徙,都影响个人和团体的社会应变能力以及基本资源基础的可持续性.社会应变能力是应对和适应通过适当的制度调节的环境和社会变化的能力.我们调查了当今越南沿海地区人口变化、社会应变能力以及可持续发展之间关系的一个侧面:迁徙和汇款对依赖于资源的人口源区居民群的影响.利用有关生活来源的纵向运动数据,我们发现移民出境和汇款对一个逐渐形成的社会和政治范围内的应变能力有抵消作用.移民出境是与不可持续的沿海养殖业的发展同时并存的,而不是起推动作用.日益增加的经济不平等削弱了社会应变能力.同时,多种经营和收入水平的不断提高有助于应变能力的增强.     

Adaptive urban governance: new challenges for the second generation of urban adaptation strategies to climate change

The task of adapting cities to the impacts of climate change is of great importance—urban areas are hotspots of high risk given their concentrations of population and infrastructure; their key roles for larger economic, political and social processes; and their inherent instabilities and vulnerabilities. Yet, the discourse on urban climate change adaptation has only recently gained momentum in the political and scientific arena. This paper reviews the recent climate change adaptation strategies of nine selected cities and analyzes them in terms of overall vision and goals, baseline information used, direct and indirect impacts, proposed structural and non-structural measures, and involvement of formal and informal actors. Against this background, adaptation strategies and challenges in two Vietnamese cities are analyzed in detail, namely Ho Chi Minh City and Can Tho. The paper thereby combines a review of formalized city-scale adaptation strategies with an empirical analysis of actual adaptation measures and constraints at household level. By means of this interlinked and comparative analysis approach, the paper explores the achievements, as well as the shortcomings, in current adaptation approaches, and generates core issues and key questions for future initiatives in the four sub-categories of: (1) knowledge, perspectives, uncertainties and key threats; (2) characteristics of concrete adaptation measures and processes; (3) interactions and conflicts between different strategies and measures; (4) limits of adaptation and tipping points. In conclusion, the paper calls for new forms of adaptive urban governance that go beyond the conventional notions of urban (adaptation) planning. The proposed concept underlines the need for a paradigm shift to move from the dominant focus on the adjustment of physical structures towards the improvement of planning tools and governance processes and structures themselves. It addresses in particular the necessity to link different temporal and spatial scales in adaptation strategies, to acknowledge and to mediate between different types of knowledge (expert and local knowledge), and to achieve improved integration of different types of measures, tools and norm systems (in particular between formal and informal approaches).     

Using fluorescence surrogates to track algogenic dissolved organic matter (AOM) during growth and coagulation/flocculation processes of green algae

Tracking the variation of the algogenic organic matter (AOM) released during the proliferation of green algae and subsequent treatment processes is crucial for constructing and optimizing control strategies. In this study, the potential of the spectroscopic tool was fully explored as a surrogate of AOM upon the cultivation of green algae and subsequent coagulation/flocculation (C/F) treatment processes using ZrCl₄ and Al₂(SO₄)₃. Fluorescence excitation emission matrix coupled with parallel factor analysis (EEM-PARAFAC) identified the presence of three independent fluorescent components in AOM, including protein-like (C1), fulvic-like (C2) and humic-like components (C3). Size exclusion chromatography (SEC) revealed that C1 in AOM was composed of large-sized proteins and aromatic amino acids. The individual components exhibited their unique characteristics with respect to the dynamic changes. C1 showed the highest correlation with AOM concentrations (R²?=?0.843) upon the C/F processes. C1 could also be suggested as an optical predictor for the formation of trihalomethanes upon the C/F processes. This study sheds a light for the potential application of the protein-like component (C1) as a practical surrogate to track the evolution of AOM in water treatment or wastewater reclamation systems involving Chlorella vulgaris green algae.     

Uptake kinetics and interaction of selenium species in tomato (Solanum lycopersicum L.) seedlings

Environmental Science and Pollution Research - Selenite and selenate are two main selenium (Se) forms absorbed by plants. The comparative effects of selenite and/or selenate on Se uptake and...     

Contamination by selected chlorinated pesticides in surface waters in Hanoi, Vietnam

Fifteen insecticides, which were banned in Vietnam in the period from 1990 to 1998, were chosen for the investigation of surface water samples in Hanoi and its surroundings. The investigation was focused on an area of approximately 30 by 20 km. Thirty water samples, in total were analysed: 11 samples from the Red river, seven from the Duong river, four from various lakes (West lake, Thuyen Quang, Bay Mau, Ba Mau), six from irrigation canals and two samples from wells. The procedure was repeated in November 1998 and in August 1999. The results showed that the contamination of the banned pesticides was highest in the rivers and then in the irrigation canals, followed by the lakes and wells. These pesticides could hardly be determined in just two drinking water samples (wells) and their concentrations rarely exceeded detection limits (0.05-0.25 ng l(-1)). The mean concentrations of sigmaHCHs (alpha, beta, gamma, delta-HCH) and sigmaDDTs (2,4'-, 4,4'-DDE; 2,4'-, 4,4'-DDD; 2,4'-, 4,4'-DDT) in the rivers were 17.2 +/- 71.8 and 43.7 +/- 79.9 ng l(-1) in the dry season (DS, November 1998), 29.3 +/- 117 and 56.1 +/- 65.6 ng l(-1) in the rainy season (RS, August 1999), respectively. However, the highest concentration of DDTs detected in a river sample (DS): 0.324 microg l(-1) was much lower than their allowable limit of concentration in surface waters, which is accorded with Criteria of Vietnam (1995) (DDTs < 10 microg l(-1)). Moreover, endrin, heptachlor, aldrin were also detected in most of water samples with considerable mean concentrations in rivers: 25.3 +/- 40.5, 17.4 +/- 23.8, 11.0 +/- 9.02 ng l(-1) in the DS and 18.5 +/- 23.2, 19.3 +/- 29.0, 12.8 +/- 8.44 ng l(-1) in the RS, respectively. Heptachlor epoxide (isomer A) and dieldrin were detected in some water samples with lowest concentrations.     

Indigenous pig production and welfare of ultra-poor ethnic minority households in the Northern mountains of Vietnam

Environment, Development and Sustainability - Eliminating ultra-poverty has received particular attention of policymakers and scholars. The ultra-poor in mountainous regions often live on...