Influence of water temperature and salinity on pH during dry season in lower Dong Nai river system, Vietnam

This paper uses the gvSIG 2.2.0 software, IDW interpolation method, river and stream network data, and 36 sampling sites to build the maps of three monitored parameters such as pH, water temperature, and salinity in the Lower Dong Nai River system (2009–2010) in dry season. Based on an analysis of these maps and statistical assessment by using the R software, the correlations between pH, temperature, and salinity are clarified. The results show that the pH and temperature values have a tendency to decrease, whereas the salinity tends to increase annually. The pH value has good and significant correlations with the water temperature and salinity in both simple and multiple linear regression models. The results aim to provide a scientific reference for further research on the water environment in this area

The long term impact of Vietnam war's veteran on economic governance

I investigate the effects of Vietnam War’s veteran on long run economic development in Vietnam. Using a unique dataset containing the number of war invalids at province levels, I find the number of war invalids from each province to be an important determinant of its current economic performance. To correct for potential biases arising from reverse causality, measurement error and unobservable province characteristics, I use an instrumental variable approach exploiting distance to the 17th parallel demilitarized zone. I also find that the importance of the war invalids for contemporary development is a result of its impacts on overall provincial economic governance and other disaggregated economic institutions, such as the pro-activity of provincial leadership, the quality of the legal institutions and services supporting business development.War invalids, economic governance, economic development, Vietnam

Zooplankton from Can Giuoc River in Southern Vietnam

In this study, the variables of zooplankton and water quality were investigated in the Can Giuoc River, Southern Vietnam. Zooplankton was monitored in April and September 2015 at 5 sampling sites in the river. Some basic water quality parameters were also tested, including pH, total suspended solid (TSS), dissolved oxygen (DO), biological oxygen demand (BOD5), inorganic nitrogen (NH4+), dissolved phosphorus (PO43-), and coliform. The zooplankton biodiversity indices were applied for the water quality assessment. The results showed that pH ranged from 6.7 to 7.6 during the monitoring. The TSSs were between 34–117 mg/L. The DO and BOD5 were from 0.6 to 3.8 mg/L and from 6.3 to 13.2 mg/L, respectively. The NH4+ and PO43- concentrations ranged from 0.44 to 3.23 and from 0.08 to 1.85 mg/L, respectively. The coliform number was between 9.3x103–9.3x104 MPN/100 mL. The zooplankton analyses showed that there were 31 species of coelenterates, rotatoria, oligochaetes, cladocerans, copepods, ostracods, mysidacea, and 8 larval types. Thereof, the species of copepods were dominant in the species number. The zooplankton density ranged from 9 500 to 23 600 individuals/m3 with the main dominant species of Moina dubia (Cladocera), Thermocyclops hyalinus, Acartia clausi, Oithona similis (Copepoda), and nauplius copepods. The biodiversity index values during the monitoring were from 1.47 to 1.79 characteristic of mesotrophic conditions of the aquatic environment. Besides, the species richness positively correlated with pH, TSS, DO, BOD5, NH4+, PO43-, and coliform, while the zooplankton densities got a positive correlation with DO, BOD5, NH4+, PO43-, and coliform. The results confirmed the advantage of using zooplankton and its indices for water quality assessment

On the sources of risk preferences in rural Vietnam

In this paper, I provide a new empirical evidence that natural environment can shape individual risk preferences. By combining historical data on climate variation and contemporary survey questions on risk aversion, I find that risk aversion is significantly different for people who live in areas that have suffered high frequency of natural disaster. In particular, individuals highly affected by climate volatility show a long term risk aversion

Cooperation makes beliefs: climate variation and sources of social trust in Vietnam

I investigate the origins of social trust within Vietnam. Combining a unique contemporary survey of households with historical data on climate variation, I show that individuals who are heavily threatened by negative climate fluctuation exhibit more trust in neighbors and other people in close group. The evidence indicates that the effects of climate variation on social trust are transmitted through strengthening the cooperation among village peasants in coping with risk and uncertainty. The results also indicate that households with higher proportion of agricultural incomes tend to rely more on village members in the case of emergency. However, the increased village relationship does not erode family ties

On the sources of risk preferences in rural Vietnam

In this paper, I provide a new empirical evidence that natural environment can shape individual risk preferences. By combining historical data on climate variation and contemporary survey questions on risk aversion, I find that risk aversion is significantly different for people who live in areas that have suffered high frequency of natural disasters. In particular, individuals highly affected by climate volatility show a long term risk aversion. The finding also supports the hypothesis that when people used to live in risky environment, an incremental increase in risk affects their risk preferences less

On the sources of risk preferences in rural Vietnam

In this paper, I provide a new empirical evidence that natural environment can shape individual risk preferences. By combining historical data on climate variation and contemporary survey questions on risk aversion, I find that risk aversion is significantly different for people who live in areas that have suffered high frequency of natural disasters. In particular, individuals highly affected by climate volatility show a long term risk aversion. The finding also supports the hypothesis that when people used to live in risky environment, an incremental increase in risk affects their risk preferences less

Cooperation makes beliefs: climate variation and sources of social trust in Vietnam

I investigate the origins of social trust within Vietnam. Combining a unique contemporary survey of households with historic data on climate variation, I show that individuals who were heavily threatened by negative climate fluctuation exhibit more trust in neighbors and other people in close group. The evidence indicates that the effects of climate variation on social trust transmitted through strengthening the cooperation among village peasants in coping with risk and uncertainty. The results also indicate that households with higher proportion of agricultural incomes tend to rely more on village members in the case of emergency. However, the increased village relationship does not erode family ties

Cooperation makes beliefs: climate variation and sources of social trust in Vietnam

I investigate the origins of social trust within Vietnam. Combining a unique contemporary survey of households with historical data on climate variation, I show that individuals who are heavily threatened by negative climate fluctuation exhibit more trust in neighbors and other people in close group. The evidence indicates that the effects of climate variation on social trust are transmitted through strengthening the cooperation among village peasants in coping with risk and uncertainty. The results also indicate that households with higher proportion of agricultural incomes tend to rely more on village members in the case of emergency. However, the increased village relationship does not erode family ties