Woranan Nakbanpote

Salt-tolerant and plant growth-promoting bacteria isolated from Zn/Cd contaminated soil: identification and effect on rice under saline conditions

The bacteria of PDMCd0501, PDMCd2007, and PDMZnCd2003 were isolated from a Zn/Cd contaminated soil. They were classified as salt-tolerant bacteria in this experiment. The bacteria had indole-3-acetic acids (IAA) production, nitrogen fixation, and phosphate solubilization, under 8% (w/v) NaCl condition. Biochemical test (API 20E) and 16S rDNA sequencing identified PDMCd2007 and PDMCd0501 as Serratia sp. and PDMZnCd2003 was Pseudomonas sp. The effect of Pseudomonas sp. PDMZnCd2003 on the germination and seedlings of Oryza sativa L.cv. RD6 was determined under a salinity of 0–16 dS/m. The salinity levels of 4–16 dS/m affected to decrease germination and seedlings of rice. Comparison between uninoculated and inoculated system, however, Pseudomonas sp. PDMZnCd2003 had a negative impact on the rice growth. This unexpected effect was a case that should be concerned and studied further before application as a plant growth-promoting bacteria (PGPB).

Phytomanagement of Padaeng Zinc Mine Waste, Mae Sot District, Tak Province, Thailand

Economic development of a nation is linked to richness of natural resources. Minerals are one of the important natural resources. Thailand is rich in minerals such as zinc (Zn), lead (Pb), tin (Sn) and gold (Au). Thailand’s largest zinc deposits are located in Phatat Phadaeng sub-district, Mae Sot, Tak. Mining operations generate huge amounts of waste which is detrimental to the quality of the local environment. Thus the waste generated by mine operations is often piled up in the vicinity of the mining site. Due to strong weather conditions, the residual metals from the piled up metallic waste get eroded and transported to the local ecosystem. Decontamination of contaminated ecosystems is complex and cost-prohibitive and thus several undesirable health effects are witnessed often. Phytomanagement deals with use of a wide variety of phytodiversity to stabilize the mine waste and thus reduce the bioavailability of toxic doses of metals. Phytomanagement also deals with control of leaching of mine waste to surrounding ecosystems and feasible options for production of safe food are dealt with in this manuscript. Phytomanagement is emerging as a potential field of phytotechnology for restoration of mine waste.

Advances in Phytoremediation Research: A Case Study of Gynura Pseudochina (L.) DC.

Phytoremediation is the process through which contaminated land is ameliorated by growing plants that have the ability to remove the contaminating chemicals. The processes in phytoremediation include phytodegradation, phytostabilization, phytovolatilization and rhizofiltration. In addition, the association of plant and microorganism in the rhizosphere seems to enhance removal of the contaminants. Although relatively slow, phytoremediation is environmentally friendly, cheap, requires little equipment or labor, is easy to perform, and sites can be cleaned without removing the polluted soil; it is an in situ method. In addition, precious metals, such as gold, zinc and chromium, collected by the hyperaccumulator can be harvested and extracted as phytoextraction. However, the key factor for successful phytoremediation is identification of a plant that is tolerant and suitable for each area, one which can accumulate high concentrations of the required metal. In addition, the mechanism of heavy metal accumulated in the plant should be studied before the application. Advance research in phytoremediation has been focused on the analysis of the distribution and speciation of metals accumulated in the hyperaccumulative plant by using synchrotron radiation and the techniques of micro-X-ray fluorescence imaging (μ-XRF imaging) and X-ray adsorption fine edge structure (XAFS). Expression of metal-inducible proteins in plant such as glutathione, methallothionine and heat-shock proteins have been extracted by various suitable extraction buffers, separated and purified by the techniques of dialysis, chromatography and gel electrophoresis. Then, the amino acid sequences, the crystal structures of proteins, and the status of the metal bound in the proteins have been studied. In addition, the microorganisms in the rhizosphere of metal hyperaccumulative plants have been investigated by isolating the bacteria that are tolerant to heavy metals and contain plant growth promoting properties; such as nitrogen fixation, phosphate solubilization, indole-3-acetic acid (IAA) phytohormone and 1-aminocyclopropane-1carboxylate (ACC) deaminase production, etc. Finally, the plant design for successful phytoremediation in any contaminated area should be concerned with ground water, running off, geology and the effect of growing the plant on biodiversity. Especially, harvesting management and byproduct utilization should be studied and investigated to convince local people and government of the usefulness of phytoremediation.

Mulberry and Vetiver for Phytostabilization of Mine Overburden: Cogeneration of Economic Products

Abstract Mining and smelting have a history of centuries. Once nature was predominant and human interference was negligible. Now, due to population explosion and increased demand for materials and energy, pollution from mine waste is glaringly visible. Coal and a variety of minerals are explored in different countries. Opencast mining generates large quantities of waste “overburden.” The intermediate layers of sandstone, shale, and gravel that are usually present between two coal seams constitute this overburden. Pollution monitoring of abandoned coal mine sites and their reclamation are some of the emerging areas of environmental science and pollution research. In this chapter two cases of phytostabilization are presented: (1) the overburdens in the West Bokaro Coalfields, India, using mulberry, and (2) the Mae Sot, Padaeng zinc mine waste stabilization using vetiver grass in Thailand. Morus alba (mulberry) cultivation on coal mine overburden and vetiver cultivation on zinc mine waste accelerated the natural attenuation processes. These two examples of plants for phytostabilization are beneficial to locals and environmental protection.

Integrated Management of Mine Waste Using Biogeotechnologies Focusing Thai Mines

The history of mining for precious minerals dates back to several centuries. Mining is important for economy but causes environmental contamination. However, mine waste reclamation and mine environment cleanup are a subject of recent origin focusing various aspects of biogeotechnologies. In general, the subject of environmental remediation is about three decades old, and today the advances in this field are capable of handling a variety of toxic waste. Different strategies and approaches are employed to render mine waste less toxic. Mining had negative effects on natural resources (biotic and abiotic) and deteriorates the quality of environment. Different types of mine industries are implicated in promoting “industrial deserts” or “lunar scapes” which are overloaded with technogenic waste. Soil washing and cleaning in such situation is cost prohibitive. This chapter deals with reclamation of a zinc, lead, and tin (arsenic) mine waste with reference to Thailand (see graphic abstract Fig. 1).

Strategies for Rehabilitation of Mine Waste/Leachate in Thailand

Abstract Geological survey indicates that Thailand has reserves for gold, silver, potassium, coal, dolomite, gypsum, and quarry mining. Thailand has a long history of mining industry. Classic examples of abandoned mines are as follows: (1) Arsenic contamination at Ron Phibun District and Nakhon Si Thammarat Province, (2) Lead contamination at Klity Creek and Kanchanaburi Province, and (3) Cadmium contamination at Mae Sot District and Tak Province. Mining in the past have affected the environment, health, and agriculture of local peoples for decades. Although modern mines have to be operated under Environment and Health Impact Assessment, Corporate Social Responsibility, tailings storage facilities, and environmental standards for mines, many mining and exploration industry in Thailand has ordered the shutdown by government due to environmental protests. If mining industries put their efforts to achieve mutual social benefit and a clean environment, the number of protestors against the mining and minerals industry will be reduced. In focusing scientific research about mining rehabilitation and remediation, both basic and apply, especially in field study, are needed as guidelines. This chapter would highlight sustainable utilization of metal polluted/contaminated lands, phytobiome and mycobiome approach for rehabilitation of mine waste, and scientific approaches for long-term monitoring of mine waste.