Bioremediation of Contaminated Lake Sediments and Evaluation of Maturity Indices as Indicators of Compost Stability
Land contamination is one of the prominent and widely addressed problems and is gaining importance in many developed and developing countries. It is now widely accepted that contaminated land is a potential threat to human health and over recent years has led to international efforts to remediate many of these sites, either as a response to the risk of adverse health or essential effects caused by contamination or to enable the site to be redeveloped for use.
Traditional methods simply move the contaminant or may create significant risk in handling the hazardous materials involving cost intensive and potential liabilities. Physical and chemical methods can be effective but are technically complex and lack public acceptance. Bioremediation is an option that offers the possibility to destroy or render harmless various contaminants using natural biological activities. It uses relatively cost-effective low technology techniques, which have high public acceptance and can be carried out on-site.
In the present study, composting is demonstrated as a full-fledged bioremediation methodology for the stabilization of contaminated lake sediments. Lab scale studies were carried out to examine the various bioprocesses occurring in composting using simulated soils and optimized conditions are established for bioremediation of lake sediments contaminated with organics and heavy metals. In order to enhance microbial activity in composting, neutralization of the contaminated lake sediments was carried out by adding commercially available lime and then, organic and inorganic fertilizers like cowdung, poultry manure, urea, and superphosphate as initial microbial seeding amendments, bulking agents like sawdust and nutrients are provided and the impact of their variation was also studied. Continuous monitoring of process control parameters like pH, moisture content, electrical conductivity, total volatile solids and various forms of nitrogen etc. were carried out.
The stability of the compost was evaluated by assessing maturity indices like C/N, Cw (water soluble carbon), CNw (Cw/Nw), nitrification index (NH4/NO3), cation exchange capacity (CEC), germination index, humification index, humification ratio, compost mineralization index (ash content/oxidizable carbon), sorption capacity index
(CEC/oxidizable carbon). Enzyme activities of agricultural interest like urease, phosphatase, b-glucosidase, dehydrogenase and BAA-hydrolyzing protease, which are involved in the nitrogen, phosphorus and carbon cycles, were also assessed. Total content of macro and micronutrients in the final compost was also determined to assess the fertilizer value.
APHA (1998). American Public Health Association, "Standard Methods for Examination of Water and Wastewater", APHA, WWA, Washington, D.C.
Akrivao, D. Mamais, Katsar, K. and A. Andreadakis (2000). Agricultural Utilisation of Lime Treated Sewage Sludge. Water Science and Technology, 42(9): 203-210.
Apitz, S.E. (1998). Streamlining contaminated sediment management: The use of advanced sediment characterization preliminary results. Water Sci. Tech., 37(6-7): 435-442.
Alef, K., Nannipieri, P. and C. Traser-Cepeda (1995). Phosphatase activity. In: Alef, K., Nannipieri, P. (Eds.), Methods in Applied soil microbiology and biochemistry. Academic Press, London. pp 335-336.
Alef, K. (1991). MethodenhandbuchBodenmikrobiologie. Econied, Landsberg/Lech, Germany.
Ayuso, M., Hernandez, T., Garcia, C. and J.A. Pascual (1996). Biochemical and chemical structural characterization of different organic materials used as manures. Bioresource Technol, 57: 201-207.
Baudo, R., Daria Rossi and Nomca Beltrami (2001). In-situ toxicity testing of lake Orta sediments. J. Limnol, 60(2): 277-284.
Benefield, C.B., Howard, P.J.A. and D.M. Howard (1997). The estimation of dehydrogenase activity in soil. Soil. Biol. Biochem, 6: 67-70.
Bernal, M.P., Paredes, C., Monedero, M.A. and J. Cegarra(1998). Maturity and stability parameters of composts prepared with a wide range of organic wastes. Bioresource Technol., 63: 91-99
Bertoldi, de M., Valini, G. and A. Pera (1983). The biology of 176.
Bishop, P.L. and C. Godfrey (1983). Nitrogen transformation during sludge composting. Biocycle, 24: 122-127.
Brady, N.C. (1974). The Nature and Properties of Soils. 8th Edition MacMillan, New York.
Brown Jr., J.F. and R.E. Wagner (1990). PCB movement dechlorination and detoxification in Acushnet estuarine. Environ. Toxicol. Chem., 9: 1215-1233.
Ceccanti, B. and C. Garcia (1994). Coupled chemical and biochemical methodologies to characterize and composting process and the humic substances. In: Senesi, N., Miano, T.M (Eds), Humic Substances in the Global Environment and Implications on Humic Health, Elsevier, Amsterdam, pp. 1279-1284.
Chefetz, B., Hatcher, P.G., Hadar, Y. and Y. Chen (1996). Chemical and biological characterization of organic matter during composting of municipal solid waste. Journal of Environmental Quality, 25: 776-785.
Colleran, E. (1997). Uses of bacteria in bioremediation. In: Sheehaw, D. (Ed.), Methods in Biotechnology, Vol 2. Bioremediation protocols. Human Press, New Jersey, pp 3-22.
Garcia, C., Hernandez T., Costa, F., C. Ceccanti and G. Masciandaro (1993). The dehydrogenase activity in soil as an ecological marker in process of perturbated system regeneration. Proc.XI International Symposium of Environmental Biogeochemistry, Salamanca (Spain) 27- 30 September.
Garcia, C., Hernandez, T. and F. Costa (1991). Changes in carbon fractions during composting and maturation of organic wastes. Environmental Management, 15: 433-439.
Garcia, C., Hernandez, T. and F. Costa (1992). Composted vs. uncomposted organics. Biocycle, 33: 70-72
Garcia, C., Hernandez, T., Costa, F., Ceccanti, C. and A. Ganni(1993). Hydrolases in the organic matter fractions of sewage sludge changes with composting. Biores. Technol, 45: 47-52.
Garcia, C., Moreno, J.L., Hernandez, T., Costa, F. and A. Polo(1995). Effect of composting on sewage sludge contaminated with heavy metals. Bioresource Technol, 53: 13-19.
Garcia, C., Hernandez, T. and F. Costa (1997). Potential use of dehydrogenase activity as an index of microbial activity in degraded soils. Commun. Sci. Plant An., 28: 123-134.
Gray, K.R. and A.J. Biddlestone (1981). The composting of agricultural wastes. In: Biological Husbandry, ed. B. Stonehouse. Butterworths, London.
Gupta, P.K. (1999). Soil, Plant, Water and Fertilizer analysis. Agro Botanica, Bikaner, India.
Hayano and K. Tubaki (1985). Origin and properties of b- Glucosidase activity of a tomato-field. Soil.Biol.Biochem.17: 553-557.
Head, I.M. (1998). Bioremediation towards a credible technology. Microbiology. 144: 599-608.
Hirai, M.F., Chanyasart, V. and H. Kubota (1983). A standard measurement for composting maturity, Biocycle, 24: 54-56.
Hsu, J.H. and S.L. Lo (1999). Chemical and spectroscopic analyses of organic matter transformations during composting of peg manure. Environmental Pollution, 104: 189-196.
Iglesias-Jimenez, E. and V. Perez-Garcia (1992). Determination of maturity indices for city refuse composts agric. Ecosystems environ. 38: 331-343.
Inbar, Y., Chen, Y. and Y. Hadan (1990). Humic Substances formed during the composing of organic matter. Soil. Sci. Soc. Am. J., 54: 1316-1323.
Jerzy Drozd, Elzbieta Jamroz, Michael Lieznar, Stanislawa E.Licznar and Jerzy Weber (1997). Organic Matter Transformation and Humic Indices of Compost Maturity Stage during Composting of Municipal Solid Wastes. In: J.Drozd, S.S. Gonet, N. Senesi, J.Weber (Eds).The Role of Humic Substances in the Ecosystems and in Environmental Protection. IHSS-Polish Society of Humic Substances, Grunwaldzka 53, 50-357 Wroclaw, Poland
Kapetanios, E.G., Ioizidon. M. and G. Volkanas (1993). Compost production from Greek domestic refuse. Bioresource Technology, 44: 13-16.
Kirchmann, H. and P. Widen (1994). Separately collected organic household wastes. Swedish. J. Agric. Res., 24: 3-12.
Knaebel, D.B., Federle, T.W., McAvoy D.C. and J.R. Vestal(1994). Effect of mineral and organic soil constituents on microbial mineralization of organic compounds in a natural soil. Applied and Environmental Microbiology, 60(12): 4500-4508.
Lake, J.L., Pruell, R.J. and F.A. Osterman (1992). An examination of dechlorination process and pathways in new Bedford Harbor sediments. Mar Environ. Res. 33: 31-47.
Lax, A., Roig, A. and F. Costa (1986). A method for determining the cation exchange capacity of organic materials. Plant Soil, 94: 349-355.
Mahimairaja, S., Bolan, N.S., Hedley, M.J. and A.X. McGregor(1994). Losses and transformations of nitrogen during composting of poultry manure with different amendments: An incubation experiment. Bioresour. Technol., 47: 265-273.
Mathur, S.P., Dinel, H., Owen, G., Schnitzer, M. and J. Dugan(1993). Determination of compost biomaturity. II. Optical density of water extracts of composts as a reflection of their maturity. Biological Agriculture and Horticulture, 10: 87-108.
McCarty, G.W., Shogren, D.R. and J.M. Bremner (1992). Regulation of urease production in soil by microbial assimilation of nitrogen. Biol. Fert, Soils.,12: 261-264.
Miller, F.C. and M.S. Finstein (1985). Materials balance in the composting of wastewater sludge as affected by process control. J.Wat. Pollut. Contr. Fed., 57: 122-127.
Nannipieri, P., Ceccanti, B., Conti, C. and D. Bianchi (1982). Hydrolases extracted from soil and their properties and activities. Soil Biology and Chemistry, 20: 257-263.
Rao, N., Grethlin,H.E. and C.A. Reddy (1995). Effect of C/N ratio and moisture content on the composting of polar wood. Biotechnol. Lett. 17(8): 889-892.
Sesay, A.A., Lasaridi, K., Stentiford, E. and T. Budd (1997). Controlled composting of paper pulp sludge using the aerated static pile method. Compost. Sci. Util, 5(1): 82-96.
Stratton, M.L., Barker, A.V. and J.E. Rechcigl (1998). Agronomic benefits of agricultural, municipal and industrial by-products and their co-utilization: an overview. In: Brown, S., Angle, J.S. and Jacobs, L. (Editors). Beneficial Co-utilization of Agricultural, Municipal and Industrial by- products. Kluwer Academic Publishers, Netherlands. p 934.
Tabatabai, M.A. and J.M. Bremner (1969).Use of r-Nitrophenolphosphate assay of soil phosphatase activity. Soil. Biol. Biochem., 1: 301-307.
Tiquia, S.M., Tam, N.F.Y. and I.J. Hodgkis (1996). Effects of composting on phytotoxicity of spent pig-manure sawdust litter. Environ. Pollut. 93: 249-256.
Tiquia, S.M. and N.F.Y. Tam (2000). Fate of nitrogen during composting of chicken litter, Environ. Pollution 110: 535-541.
Trevors, J.T. (1984). Dehydrogenase activity in soil. A comparison between the INT and TTC assay. Soil. Biol. Biochem. 16: 673-674
Vidali, M. (2001). Bioremediationn Overview. Pure Appl. Chem., 73(7): 1163-1172.
Zucconi, F. and M. de Bertoldi (1987). Compost specifications for the production and characterization of compost from municipal solid waste. In: Compost: Production, quality F. Zucconic. Elservier Applied Science, Essex, pp 30-50.
Zucconi, F., Forte, M., Monaco, A. and M. de Bertoldi (1981). Biological evaluation of compost maturity. Biocycle 22: 27-29.