PHYTOREMEDIATION

Environment topic(civil engineering)-PHYTOREMEDIATION

1. PHYTOREMEDIATION DAYAL KURIAN VARGHESE

2. OVERVIEW INTRODUCTION OF PHYTOREMEDIATION NEED FOR THE NEW REMEDIATION TECHNIQUE VARIOUS PHYTOREMEDIATION PROCESSES PHYTOREMEDIATION BY AQUATIC PLANTS ADVANTAGES AND DISADVANTAGES CONCLUSION

3. INTRODUCTION Phytoremediation can be defined as the use of green plants to remove the contaminants from the environment or to render them harmless. “Phyto”= Plant (in Greek) “Remediare”= To remedy (in Latin)

4. NEED FOR THE NEW REMEDIATION TECHNIQUE Microbial/ Biological Measures These approaches are ecological and economically sound but physical removal/ cleaning up of contaminants does not occurs as contaminants remain in the soil system Chemical Measures Chemical extraction procedures have been suggested but they are not cost effective. So, these constraints have forced the researcher to think of using plants for cleaning up their own support system which will eco-friendly and cost effective. This new approach is “Phytoremediation”.

5. VARIOUS PHYTOREMEDIATION PROCESSES Phytoextraction Rhizofiltration Phytostabilization Phytotransformation Rhizosphere Bioremediation

6. PHYTOEXTRACTION Phytoextraction uses plants or algae to remove contaminants from soils, sediments or water into harvestable plant biomass . The main advantage of phytoextraction is environmental friendliness.

7. PHYTOSTABILISATION Phytostabilization is the use of plants to prevent the migration of contaminants through control of the hydraulic gradient or by reinforcing the soil structure.

8. PHYTOTRANSFORMATION chemical modification of environmental substances as a result of plant metabolism resulting in their inactivation, degradation (phytodegradation) or immobilization (phytostabilization).

9. RHIZOFILTRATION  Filtering water through a mass of roots to remove toxic substances or excess nutrients. The pollutants remain absorbed in or adsorbed to the roots. Chernobyl - sunflowers were grown in radioactively contaminated pools

10. RHIZOSPHERE BIOREMEDIATION Enhancement of soil microbial activity for the degradation of contaminants, typically by organisms that associate with roots. Rhizosphere = soil + root + microbes. Also known as Phytostimulation.

11. PHYTOREMEDIATION BY AQUATIC PLANTS Aquatic plants are those plants living in and adapted to aquatic environments, which can only grow in water or permanently saturated soil. Eurasian Watermilfoil ( Myriophyllum spicatum ) Water Hyacinth ( Eichhornia crassipes ) Duckweed ( Lemna trisulca L.) Fool's Watercress ( Apium nodiflorum )

12. Water Hyacinth Floating plant with broad ,thick, and glossy leaves that the plant body can grow as much as 1m high. Able to phytoaccumulate metal pollutants contain Ag, Pb , Cd and Zn in municipal and agricultural wastewater. Known as one of the plants with fastest growth rate that can double population in 2 weeks. High invasive potential.

13. Case Study: Removal of Cadmium and Zinc by Water Hyacinth The stock solution was prepared in distilled water with analytical grade CdCl 2 . 2½ H 2 O and ZnSO 4 .7H 2 O which was later diluted as required. The plants were maintained in tap water with concentrations of 0.5, 1, 2, 4 mg/L of Cd and 5, 10, 20, 40 mg/L of Zn. The test durations were 0 (two hours), 4, 8 and 12 days. Relative growth, metal accumulation, and bioconcentration factor (BCF) are evaluated. Relative growth (above) and BCF (below)

14. Zn Cd Cd Zn Cd Zn (Lu et al., 2004) Relative plant growth Metal Accumulation BCF

15. Duckweed Has a very simple structure that lacks obvious stems or leaves, with small plate-shaped structure floating on water surface. Reproduction is mainly rely on asexual budding. High pollutant removal potential due to small size, fast growth, and easy to cluture . (Kara and Kara, 2004)

16. The duckweed obtained from natural lake was acclimatized to laboratory conditions for one week before starting research. Solution of Cadmium was prepared using Cd (NO 3 ) 2 and contact with plant sample for different length. After absorption, water samples were analyzed by AAS at 228.8nm . Case Study: Removal of Cadmium by Duckweed Cd removal efficiencies (Kara and Kara, 2004)

17. ADVANTAGES AND DISADVANTAGES Advantages Disadvantages Cost effective when compared to other more conventional methods. Slow rate and difficult to achieve acceptable levels of decontamination. “natural” method, more aesthetically pleasing. Possibility of contaminated plants entering the food chain. minimal land disturbance. Possible spread of contaminant through falling leaves. reduces potential for transport of contaminants by wind/soil erosion. Trees and plants require care. multiple contaminants can be removed with the same plant. Contaminant might kill the tree. It is one of the least harmful method. Degradation product could be worse than original contaminant. The possibility of recovery and reuse of valuable metals.( Phyto mining) Only surface soil (root zone) can be treated. Cleanup takes several years.

18. CONCLUSION Although much remains to be studied, Phytoremediation will clearly play some role in the stabilization and remediation of many contaminated sites. The main factor driving the implementation of Phytoremediation projects are low costs with significant improvements in site aesthetics and the potential for ecosystem restoration.

19. REFERENCES: Majeti Narasimha Vara Prasad,et al, “Metal hyperaccumulation in plants - Biodiversity prospecting for phytoremediation technology”, Electronic Journal of Biotechnology 6(3),2003,450 -458. Yeşim Kara,et al, ” Removal of Cadmium from Water Using Duckweed ( Lemna trisulca L.)”, International Journal Of Agriculture & Biology 4,2005,660-662. Angela Pierre Vitória,et al, ” Structural and Ecophysiological Alterations of the Water Hyacinth [ Eichhornia crassipes (Mart.) Solms ] Due to Anthropogenic Stress in Brazilian Rivers”, Brazilian Archives Of Biology And Technology 54(5),2011, 1059-1068. Mesania Rizwana,et al, ” Phytoremediation of Textile Waste Water Using Potential Wetland Plant: Eco Sustainable Approach”, International Journal of Interdisciplinary and Multidisciplinary Studies (IJIMS) 1(4),2014,130-138.

20. REFERENCES(CONTD.) Divya Singh,et al, “ Phytoremediation of lead from wastewater using aquatic plants”, Journal of Agricultural Technology 8(1),2012,1-11. Honey Aggarwal,et al, “ Phytoremediation of some heavy metals by agronomic crops”, Developments in Environmental Science 5,2007,79-98. Hiromichi Morikawa,et al, “Basic processes in phytoremediation and some applications to air pollution control”, Chemosphere 52,2003, 1553-1558. Hongyu Wang,et al, “An Application of Phytoremediation to River Pollution Remediation”, Procedia Environmental Sciences 10 ,2011 ,1904 – 1907.

21. THANKS! Any questions?