Research
Effect of Heavy Metals on Plant Growth and Ability to use Fertilizing Substances to Reduce Heavy Metal Accumulation by Brassica Juncea L. Czern
Heavy metal pollution in soil and water is a global environmental concern. In Vietnam, accumulation of heavy metals in soil, water and plant biomass has been widely reported. Cultivation of crops on contaminated sites may result in both growth inhibition and tissue accumulation of heavy metals with resulting possible risks to humans health. In this paper, plant growth inhibition and accumulation of Cu, Pb and Zn by Brassica juncea L. Czern are studied in pot experiments.
The Ability of Sludge from Wastewater Treatment Systems of Paper Plant to Improve Soil Fertility and Crop Growth
In Vietnam, the sludge from wastewater treatment systems in general and from the paper mill in particular is quite large. Particularly, an estimated 14,500 tons of sludge are generated annually from only the paper industry. However, at present mainly these sludge are applied forms of burial in landfills. It has caused difficulties for the construction of the landfill and waste of resources. Therefore, this study aims to investigate the possibility of using sludge as fertilizer to soil and crop improvement, and contribute to environmental protection. The results show that sludge from wastewater treatment systems of paper plant has high organic matter content (28.76% of organic C), rich in N (1.07%) and other nutrients such as P, Ca, Mg that should be used as fertilizer to improvement of soil fertility, and contribute increasing crop production. In this research, the sludge has a positive impact on soil properties, especially contributed significantly improve the amount of available nitrogen and soil humus. The high sludge applied generally produced greater biomass and crop yields. It is recommended that application of 10; 20 and 30 tons of sludge per ha have increased the pod yields of peanuts by 128; 144 and 155% compared to the control without application of sludge.
