Production and Application of Organic Waste Compost for Urban Agriculture in Emerging Cities
Composting is one of the conventional techniques adopted for organic waste management but the practice is very limited in emerging cities despite that most of the waste generated is organic. This paper aims to examine the viability of composting for organic waste management in the emerging city of Addis Ababa, Ethiopia by addressing the composting practice, quality of compost and application of compost in urban agriculture. The study collects data using compost laboratory testing and urban farm households’ survey and uses descriptive analysis on the state of compost production and application, physicochemical analysis of the compost samples, and regression analysis on the urban farmer’s willingness to pay for compost. The findings of the study indicated that there is composting practice at a small scale, most of the producers use unsorted feedstock materials, aerobic composting is dominantly used and the maturation period ranged from four to 10 weeks. The carbon content of the compost ranges from 30.8 to 277.1 due to the type of feedstock applied and this surpasses the ideal proportions for C:N ratio. The total nitrogen, pH, organic matter and moisture content are relatively optimal. The levels of heavy metals measured for Mn, Cu, Pb, Cd and Cr6+ in the compost samples are also insignificant. In the urban agriculture sector, chemical fertilizer is the dominant type of soil input in crop productions but vegetable producers use a combination of both fertilizer and other organic inputs including compost. The willingness to pay for compost depends on income, household size, gender, type of soil inputs, monitoring soil fertility, the main product of the farm, farming method and farm ownership. Finally, this study recommends the need for collaboration among stakeholders along the value chain of waste, awareness creation on the benefits of composting and addressing challenges faced by both compost producers and users.
[1] A. Mesjasz-Lech, “Municipal Waste Management in Context of Sustainable Urban Development,” Procedia - Soc. Behav. Sci., vol. 151, pp. 244 – 256, 2014, doi: 10.1016/j.sbspro.2014.10.023.
[2] N. Regassa, R. D. Sundaraa, and B. B. Seboka, “Challenges and Opportunities in Municipal Solid Waste Management: The Case of Addis Ababa City, Central Ethiopia,” J. Hum. Ecol., vol. 33, no. 3, pp. 179–190, 2011, doi: 10.1080/09709274.2011.11906358.
[3] A. T. T. Gonçalves, F. T. F. Moraes, G. L. Marques, J. P. Lima, and R. da S. Lima, “Urban solid waste challenges in the BRICS countries: A systematic literature review,” Rev. Ambient. e Agua, vol. 13, no. 2, p. e2157, 2018, doi: 10.4136/ambi-agua.2157.
[4] M. H. Sabki, C. T. Lee, C. P. C. Bong, and J. J. Klemeš, “A review on the economic feasibility of composting for organic waste management in Asian countries,” Chem. Eng. Trans., vol. 70, pp. 49–54, 2018, doi: 10.3303/CET1870009.
[5] S. Kaza, L. Yao, P. Bhada-Tata, and F. Van Woerden, What a Waste 2.0: A Global Snapshot of Solid Waste Management to 2050. Washington, DC: World Bank, 2018.
[6] IPCC, “Guidelines for National Greenhouse Gas Inventories, Prepared by the National Greenhouse Gas Inventories Programm,” N. T. and T. K. Eggleston H.S., Buendia L., Miwa K., Ed. IGES, Japan, 2006.
[7] P. R. Kumar, A. Jayaram, and R. K. Somashekar, “Assessment of the performance of different compost models to manage urban household organic solid wastes,” Clean Technol. Environ. Policy, vol. 11, pp. 473–484, 2009, doi: 10.1007/s10098-009-0204-9.
[8] H. Jouhara et al., “Municipal waste management systems for domestic use,” Energy, vol. 139, pp. 485–506, 2017, doi: 10.1016/j.energy.2017.07.162.
[9] R. D. Piacentini and M. Vega, “Comparative Analysis of the Possibility to Use Urban Organic Waste for Compost or Biogas Productions. Application to Rosario City, Argentina,” in IOP Conference Series: Materials Science and Engineering, 2017, vol. 245, p. 052029, doi: 10.1088/1757-899X/245/5/052029.
[10] H. I. Abdel-Shafy and M. S. M. Mansour, “Solid waste issue: Sources, composition, disposal, recycling, and valorization,” Egypt. J. Pet., vol. 27, pp. 1275–1290, 2018, doi: 10.1016/j.ejpe.2018.07.003.
[11] L. J.-M. Thuriès et al., “Cash for trash: an agro-economic value assessment of urban organic materials used as fertilizers in Cameroon,” Agron. Sustain. Dev., vol. 39, no. 6, p. 52, 2019, doi: 10.1007/s13593-019-0598-7.
[12] A. A. Kadir, N. W. Azhari, and S. N. Jamaludin, “An overview of organic waste in composting,” in MATEC Web of Conferences, 2016, vol. 47, p. 05025, doi: 10.1051/matecconf/20164705025.
[13] C. R. Lohri, S. Diener, I. Zabaleta, A. Mertenat, and C. Zurbrügg, “Treatment technologies for urban solid biowaste to create value products: a review with focus on low- and middle-income settings,” Rev. Environ. Sci. Biotechnol., vol. 16, pp. 81–130, 2017, doi: 10.1007/s11157-017-9422-5.
[14] B. K. Terfa, N. Chen, D. Liu, X. Zhang, and D. Niyogi, “Urban expansion in Ethiopia from 1987 to 2017: Characteristics, spatial patterns, and driving forces,” Sustainability, vol. 11, p. 2973, 2019, doi: 10.3390/su11102973.
[15] World Bank, “Addis Ababa, Ethiopia, Enhancing City Resilience,” Washington, D.C., D.C., 2015.
[16] UN-Habitat, “The State of Addis Ababa 2017: The Addis Ababa we Want,” Nairobi, Kenya, 2017. [Online]. Available: https://unhabitat.org/books/the-state-of-addis-ababa-2017-the-addis-ababa-we-want/.
[17] EDRI and GGGI, “Unlocking the Power of Ethiopia’s Cities: A report by Ethiopia’s New Climate Economy Partnership,” 2015.
[18] ARTELIA, “Solid Waste Management Project Strategic and Technical Studies and Original Works Supervision. Final Report,” Addis Ababa, Ethiopia, 2013.
[19] P. Lamson-Hall, S. Angel, D. DeGroot, R. Martin, and T. Tafesse, “A new plan for African cities: The Ethiopia Urban Expansion Initiative,” Urban Stud., pp. 1–16, 2019, doi: 10.1177/0042098018757601.
[20] T. Yamane, Statistics; An Introductory Analysis, 2nd Ed. New York: Harper and Row, 1967.
[21] G. M. Shah et al., “Composting of municipal solid waste by different methods improved the growth of vegetables and reduced the health risks of cadmium and lead,” Environ. Sci. Pollut. Res., vol. 26, no. 6, pp. 5463–5474, 2019, doi: 10.1007/s11356-018-04068-z.
[22] H. Yu, B. Xie, R. Khan, and G. Shen, “The changes in carbon, nitrogen components and humic substances during organic-inorganic aerobic co-composting,” Bioresour. Technol., vol. 271, no. 11, pp. 228–235, 2019, doi: 10.1016/j.biortech.2018.09.088.
[23] J. Gabhane et al., “Additives aided composting of green waste: Effects on organic matter degradation, compost maturity, and quality of the finished compost,” Bioresour. Technol., vol. 114, pp. 382–388, 2012, doi: 10.1016/j.biortech.2012.02.040.
[24] L. Liu, S. Wang, X. Guo, T. Zhao, and B. Zhang, “Succession and diversity of microorganisms and their association with physicochemical properties during green waste thermophilic composting,” Waste Manag., vol. 73, pp. 101–112, 2018, doi: 10.1016/j.wasman.2017.12.026.
[25] Ç. Akyol, O. Ince, and B. Ince, “Crop-based composting of lignocellulosic digestates: Focus on bacterial and fungal diversity,” Bioresour. Technol., vol. 288, no. May, p. 121549, 2019, doi: 10.1016/j.biortech.2019.121549.
[26] M. K. Manu, R. Kumar, and A. Garg, “Decentralized composting of household wet biodegradable waste in plastic drums: Effect of waste turning, microbial inoculum and bulking agent on product quality,” J. Clean. Prod., vol. 226, pp. 233–241, 2019, doi: 10.1016/j.jclepro.2019.03.350.
[27] P. J. Longhurst et al., “Risk assessments for quality-assured, source-segregated composts and anaerobic digestates for a circular bioeconomy in the UK,” Environ. Int., vol. 127, no. December 2018, pp. 253–266, 2019, doi: 10.1016/j.envint.2019.03.044.
[28] T. Mukama et al., “Practices, Concerns, and Willingness to Participate in Solid Waste Management in Two Urban Slums in Central Uganda,” J. Environ. Public Health, vol. 2016, no. 6830163, p. 7, 2016, doi: 10.1155/2016/6830163.
[29] A. Mertenat, S. Diener, and C. Zurbrügg, “Black Soldier Fly biowaste treatment – Assessment of global warming potential,” Waste Manag., vol. 84, pp. 173–181, 2019, doi: 10.1016/j.wasman.2018.11.040.
[30] Y. Vögeli, C. Riu, A. Gallardo, S. Diener, and C. Zurbrügg, Anaerobic Digestion of Biowaste in Developing Countries: Practical Information and Case Studies. Dübendorf, Switzerland, 2014.
[31] D. Sharma, V. S. Varma, K. D. Yadav, and A. S. Kalamdhad, “Evolution of chemical and biological characterization during agitated pile composting of flower waste,” Int. J. Recycl. Org. Waste Agric., vol. 6, no. 1, pp. 89–98, 2017, doi: 10.1007/s40093-017-0155-9.
[32] C. R. Sudharmaidevi, K. C. M. Thampatti, and N. Saifudeen, “Rapid production of organic fertilizer from degradable waste by thermochemical processing,” Int. J. Recycl. Org. Waste Agric., vol. 6, no. 1, pp. 1–11, 2017, doi: 10.1007/s40093-016-0147-1.
[33] H. Avci, “Trace metals in vegetables grown with municipal and industrial wastewaters,” Toxicol. Environ. Chem., vol. 94, no. 6, pp. 1125–1143, 2012, doi: 10.1080/02772248.2012.691501.
[34] Ó. J. Sánchez, D. A. Ospina, and S. Montoya, “Compost supplementation with nutrients and microorganisms in composting process,” Waste Manag., vol. 69, no. 26, pp. 136–153, 2017, doi: 10.1016/j.wasman.2017.08.012.
[35] Pilar Román, M. M. M. A. Pantoja, and Food, Farmer´s compost handbook. Food and Agriculture Organization of the United Nations Regional Office for Latin America and the Caribbean, 2015.
[36] M. A. Khan, X. Ding, S. Khan, M. L. Brusseau, A. Khan, and J. Nawab, “The influence of various organic amendments on the bioavailability and plant uptake of cadmium present in mine-degraded soil,” Sci. Total Environ., vol. 636, pp. 810–817, 2018, doi: 10.1016/j.scitotenv.2018.04.299.
[37] T. E. Manungufala, L. Chimuka, and B. X. Maswanganyi, “Evaluating the quality of communities made compost manure in South Africa: A case study of content and sources of metals in compost manure from Thulamela Municipality, Limpopo province,” Bioresour. Technol., vol. 99, no. 5, pp. 1491–1496, 2008, doi: 10.1016/j.biortech.2007.02.006.
[38] G. Danso, S. C. Fialor, and P. Drechsel, Farmers’ perception and willingness to pay for urban waste compost in Ghana. Southampton: UK: WIT Press, 2002, pp. 231–241.
[39] G. Danso, P. Drechsel, S. Fialor, and M. Giordano, “Estimating the demand for municipal waste compost via farmers’ willingness-to-pay in Ghana,” Waste Manag., vol. 26, pp. 1400–1409, 2006, doi: 10.1016/j.wasman.2005.09.021.
[40] J. Rouse, S. Rothenberger, and C. Zurbrügg, Marketing Compost: A Guide for Compost Producers in Low and Middle-Income Countries. Eawag: Swiss Federal Institute of Aquatic Science and Technology, 2008.
[41] G. Danso, M. Otoo, W. Ekere, S. Ddungu, and G. Madurangi, “Market feasibility of faecal sludge and municipal solid waste-based compost as measured by farmers’ willingness-to-pay for product attributes: Evidence from Kampala, Uganda,” Resources, vol. 6, no. 3, p. 31, 2017, doi: 10.3390/resources6030031.
[42] Addis Ababa City Planning Project Office, “Addis Ababa City Structure Plan: Draft final summary Report (2017-2027),” 2017.
[43] Addis Ababa City Urban Agriculture Office, “Performance of the urban agriculture sector in Addis Ababa,” 2017.
[44] H. Insam, I. Franke-Whittle, and M. Goberna, “Microbes in Aerobic and Anaerobic Waste Treatment,” in Microbes at Work: From Wastes to Resources, H. Insam, I. Franke-Whittle, and M. Goberna, Eds. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010, pp. 1–34.
[45] I. Angelidaki, A. S. Mogensen, and B. K. Ahring, “Degradation of organic contaminants found in organic waste,” Biodegradation, vol. 11, no. 6, pp. 377–383, 2000, doi: 10.1023/A:1011643014990.
[46] A. S. Erses, T. T. Onay, and O. Yenigun, “Comparison of aerobic and anaerobic degradation of municipal solid waste in bioreactor landfills,” Bioresour. Technol., vol. 99, no. 13, pp. 5418–5426, Sep. 2008, doi: 10.1016/j.biortech.2007.11.008.
[1] A. Mesjasz-Lech, “Municipal Waste Management in Context of Sustainable Urban Development,” Procedia - Soc. Behav. Sci., vol. 151, pp. 244 – 256, 2014, doi: 10.1016/j.sbspro.2014.10.023.
[2] N. Regassa, R. D. Sundaraa, and B. B. Seboka, “Challenges and Opportunities in Municipal Solid Waste Management: The Case of Addis Ababa City, Central Ethiopia,” J. Hum. Ecol., vol. 33, no. 3, pp. 179–190, 2011, doi: 10.1080/09709274.2011.11906358.
[3] A. T. T. Gonçalves, F. T. F. Moraes, G. L. Marques, J. P. Lima, and R. da S. Lima, “Urban solid waste challenges in the BRICS countries: A systematic literature review,” Rev. Ambient. e Agua, vol. 13, no. 2, p. e2157, 2018, doi: 10.4136/ambi-agua.2157.
[4] M. H. Sabki, C. T. Lee, C. P. C. Bong, and J. J. Klemeš, “A review on the economic feasibility of composting for organic waste management in Asian countries,” Chem. Eng. Trans., vol. 70, pp. 49–54, 2018, doi: 10.3303/CET1870009.
[5] S. Kaza, L. Yao, P. Bhada-Tata, and F. Van Woerden, What a Waste 2.0: A Global Snapshot of Solid Waste Management to 2050. Washington, DC: World Bank, 2018.
[6] IPCC, “Guidelines for National Greenhouse Gas Inventories, Prepared by the National Greenhouse Gas Inventories Programm,” N. T. and T. K. Eggleston H.S., Buendia L., Miwa K., Ed. IGES, Japan, 2006.
[7] P. R. Kumar, A. Jayaram, and R. K. Somashekar, “Assessment of the performance of different compost models to manage urban household organic solid wastes,” Clean Technol. Environ. Policy, vol. 11, pp. 473–484, 2009, doi: 10.1007/s10098-009-0204-9.
[8] H. Jouhara et al., “Municipal waste management systems for domestic use,” Energy, vol. 139, pp. 485–506, 2017, doi: 10.1016/j.energy.2017.07.162.
[9] R. D. Piacentini and M. Vega, “Comparative Analysis of the Possibility to Use Urban Organic Waste for Compost or Biogas Productions. Application to Rosario City, Argentina,” in IOP Conference Series: Materials Science and Engineering, 2017, vol. 245, p. 052029, doi: 10.1088/1757-899X/245/5/052029.
[10] H. I. Abdel-Shafy and M. S. M. Mansour, “Solid waste issue: Sources, composition, disposal, recycling, and valorization,” Egypt. J. Pet., vol. 27, pp. 1275–1290, 2018, doi: 10.1016/j.ejpe.2018.07.003.
[11] L. J.-M. Thuriès et al., “Cash for trash: an agro-economic value assessment of urban organic materials used as fertilizers in Cameroon,” Agron. Sustain. Dev., vol. 39, no. 6, p. 52, 2019, doi: 10.1007/s13593-019-0598-7.
[12] A. A. Kadir, N. W. Azhari, and S. N. Jamaludin, “An overview of organic waste in composting,” in MATEC Web of Conferences, 2016, vol. 47, p. 05025, doi: 10.1051/matecconf/20164705025.
[13] C. R. Lohri, S. Diener, I. Zabaleta, A. Mertenat, and C. Zurbrügg, “Treatment technologies for urban solid biowaste to create value products: a review with focus on low- and middle-income settings,” Rev. Environ. Sci. Biotechnol., vol. 16, pp. 81–130, 2017, doi: 10.1007/s11157-017-9422-5.
[14] B. K. Terfa, N. Chen, D. Liu, X. Zhang, and D. Niyogi, “Urban expansion in Ethiopia from 1987 to 2017: Characteristics, spatial patterns, and driving forces,” Sustainability, vol. 11, p. 2973, 2019, doi: 10.3390/su11102973.
[15] World Bank, “Addis Ababa, Ethiopia, Enhancing City Resilience,” Washington, D.C., D.C., 2015.
[16] UN-Habitat, “The State of Addis Ababa 2017: The Addis Ababa we Want,” Nairobi, Kenya, 2017. [Online]. Available: https://unhabitat.org/books/the-state-of-addis-ababa-2017-the-addis-ababa-we-want/.
[17] EDRI and GGGI, “Unlocking the Power of Ethiopia’s Cities: A report by Ethiopia’s New Climate Economy Partnership,” 2015.
[18] ARTELIA, “Solid Waste Management Project Strategic and Technical Studies and Original Works Supervision. Final Report,” Addis Ababa, Ethiopia, 2013.
[19] P. Lamson-Hall, S. Angel, D. DeGroot, R. Martin, and T. Tafesse, “A new plan for African cities: The Ethiopia Urban Expansion Initiative,” Urban Stud., pp. 1–16, 2019, doi: 10.1177/0042098018757601.
[20] T. Yamane, Statistics; An Introductory Analysis, 2nd Ed. New York: Harper and Row, 1967.
[21] G. M. Shah et al., “Composting of municipal solid waste by different methods improved the growth of vegetables and reduced the health risks of cadmium and lead,” Environ. Sci. Pollut. Res., vol. 26, no. 6, pp. 5463–5474, 2019, doi: 10.1007/s11356-018-04068-z.
[22] H. Yu, B. Xie, R. Khan, and G. Shen, “The changes in carbon, nitrogen components and humic substances during organic-inorganic aerobic co-composting,” Bioresour. Technol., vol. 271, no. 11, pp. 228–235, 2019, doi: 10.1016/j.biortech.2018.09.088.
[23] J. Gabhane et al., “Additives aided composting of green waste: Effects on organic matter degradation, compost maturity, and quality of the finished compost,” Bioresour. Technol., vol. 114, pp. 382–388, 2012, doi: 10.1016/j.biortech.2012.02.040.
[24] L. Liu, S. Wang, X. Guo, T. Zhao, and B. Zhang, “Succession and diversity of microorganisms and their association with physicochemical properties during green waste thermophilic composting,” Waste Manag., vol. 73, pp. 101–112, 2018, doi: 10.1016/j.wasman.2017.12.026.
[25] Ç. Akyol, O. Ince, and B. Ince, “Crop-based composting of lignocellulosic digestates: Focus on bacterial and fungal diversity,” Bioresour. Technol., vol. 288, no. May, p. 121549, 2019, doi: 10.1016/j.biortech.2019.121549.
[26] M. K. Manu, R. Kumar, and A. Garg, “Decentralized composting of household wet biodegradable waste in plastic drums: Effect of waste turning, microbial inoculum and bulking agent on product quality,” J. Clean. Prod., vol. 226, pp. 233–241, 2019, doi: 10.1016/j.jclepro.2019.03.350.
[27] P. J. Longhurst et al., “Risk assessments for quality-assured, source-segregated composts and anaerobic digestates for a circular bioeconomy in the UK,” Environ. Int., vol. 127, no. December 2018, pp. 253–266, 2019, doi: 10.1016/j.envint.2019.03.044.
[28] T. Mukama et al., “Practices, Concerns, and Willingness to Participate in Solid Waste Management in Two Urban Slums in Central Uganda,” J. Environ. Public Health, vol. 2016, no. 6830163, p. 7, 2016, doi: 10.1155/2016/6830163.
[29] A. Mertenat, S. Diener, and C. Zurbrügg, “Black Soldier Fly biowaste treatment – Assessment of global warming potential,” Waste Manag., vol. 84, pp. 173–181, 2019, doi: 10.1016/j.wasman.2018.11.040.
[30] Y. Vögeli, C. Riu, A. Gallardo, S. Diener, and C. Zurbrügg, Anaerobic Digestion of Biowaste in Developing Countries: Practical Information and Case Studies. Dübendorf, Switzerland, 2014.
[31] D. Sharma, V. S. Varma, K. D. Yadav, and A. S. Kalamdhad, “Evolution of chemical and biological characterization during agitated pile composting of flower waste,” Int. J. Recycl. Org. Waste Agric., vol. 6, no. 1, pp. 89–98, 2017, doi: 10.1007/s40093-017-0155-9.
[32] C. R. Sudharmaidevi, K. C. M. Thampatti, and N. Saifudeen, “Rapid production of organic fertilizer from degradable waste by thermochemical processing,” Int. J. Recycl. Org. Waste Agric., vol. 6, no. 1, pp. 1–11, 2017, doi: 10.1007/s40093-016-0147-1.
[33] H. Avci, “Trace metals in vegetables grown with municipal and industrial wastewaters,” Toxicol. Environ. Chem., vol. 94, no. 6, pp. 1125–1143, 2012, doi: 10.1080/02772248.2012.691501.
[34] Ó. J. Sánchez, D. A. Ospina, and S. Montoya, “Compost supplementation with nutrients and microorganisms in composting process,” Waste Manag., vol. 69, no. 26, pp. 136–153, 2017, doi: 10.1016/j.wasman.2017.08.012.
[35] Pilar Román, M. M. M. A. Pantoja, and Food, Farmer´s compost handbook. Food and Agriculture Organization of the United Nations Regional Office for Latin America and the Caribbean, 2015.
[36] M. A. Khan, X. Ding, S. Khan, M. L. Brusseau, A. Khan, and J. Nawab, “The influence of various organic amendments on the bioavailability and plant uptake of cadmium present in mine-degraded soil,” Sci. Total Environ., vol. 636, pp. 810–817, 2018, doi: 10.1016/j.scitotenv.2018.04.299.
[37] T. E. Manungufala, L. Chimuka, and B. X. Maswanganyi, “Evaluating the quality of communities made compost manure in South Africa: A case study of content and sources of metals in compost manure from Thulamela Municipality, Limpopo province,” Bioresour. Technol., vol. 99, no. 5, pp. 1491–1496, 2008, doi: 10.1016/j.biortech.2007.02.006.
[38] G. Danso, S. C. Fialor, and P. Drechsel, Farmers’ perception and willingness to pay for urban waste compost in Ghana. Southampton: UK: WIT Press, 2002, pp. 231–241.
[39] G. Danso, P. Drechsel, S. Fialor, and M. Giordano, “Estimating the demand for municipal waste compost via farmers’ willingness-to-pay in Ghana,” Waste Manag., vol. 26, pp. 1400–1409, 2006, doi: 10.1016/j.wasman.2005.09.021.
[40] J. Rouse, S. Rothenberger, and C. Zurbrügg, Marketing Compost: A Guide for Compost Producers in Low and Middle-Income Countries. Eawag: Swiss Federal Institute of Aquatic Science and Technology, 2008.
[41] G. Danso, M. Otoo, W. Ekere, S. Ddungu, and G. Madurangi, “Market feasibility of faecal sludge and municipal solid waste-based compost as measured by farmers’ willingness-to-pay for product attributes: Evidence from Kampala, Uganda,” Resources, vol. 6, no. 3, p. 31, 2017, doi: 10.3390/resources6030031.
[42] Addis Ababa City Planning Project Office, “Addis Ababa City Structure Plan: Draft final summary Report (2017-2027),” 2017.
[43] Addis Ababa City Urban Agriculture Office, “Performance of the urban agriculture sector in Addis Ababa,” 2017.
[44] H. Insam, I. Franke-Whittle, and M. Goberna, “Microbes in Aerobic and Anaerobic Waste Treatment,” in Microbes at Work: From Wastes to Resources, H. Insam, I. Franke-Whittle, and M. Goberna, Eds. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010, pp. 1–34.
[45] I. Angelidaki, A. S. Mogensen, and B. K. Ahring, “Degradation of organic contaminants found in organic waste,” Biodegradation, vol. 11, no. 6, pp. 377–383, 2000, doi: 10.1023/A:1011643014990.
[46] A. S. Erses, T. T. Onay, and O. Yenigun, “Comparison of aerobic and anaerobic degradation of municipal solid waste in bioreactor landfills,” Bioresour. Technol., vol. 99, no. 13, pp. 5418–5426, Sep. 2008, doi: 10.1016/j.biortech.2007.11.008.
@article{"International Journal of Biological, Life and Agricultural Sciences:80779", author = "Alemayehu Agizew Woldeamanuel and Mekonnen Maschal Tarekegn and Raj Mohan Balakrishina", title = "Production and Application of Organic Waste Compost for Urban Agriculture in Emerging Cities", abstract = "Composting is one of the conventional techniques adopted for organic waste management but the practice is very limited in emerging cities despite that most of the waste generated is organic. This paper aims to examine the viability of composting for organic waste management in the emerging city of Addis Ababa, Ethiopia by addressing the composting practice, quality of compost and application of compost in urban agriculture. The study collects data using compost laboratory testing and urban farm households’ survey and uses descriptive analysis on the state of compost production and application, physicochemical analysis of the compost samples, and regression analysis on the urban farmer’s willingness to pay for compost. The findings of the study indicated that there is composting practice at a small scale, most of the producers use unsorted feedstock materials, aerobic composting is dominantly used and the maturation period ranged from four to 10 weeks. The carbon content of the compost ranges from 30.8 to 277.1 due to the type of feedstock applied and this surpasses the ideal proportions for C:N ratio. The total nitrogen, pH, organic matter and moisture content are relatively optimal. The levels of heavy metals measured for Mn, Cu, Pb, Cd and Cr6+ in the compost samples are also insignificant. In the urban agriculture sector, chemical fertilizer is the dominant type of soil input in crop productions but vegetable producers use a combination of both fertilizer and other organic inputs including compost. The willingness to pay for compost depends on income, household size, gender, type of soil inputs, monitoring soil fertility, the main product of the farm, farming method and farm ownership. Finally, this study recommends the need for collaboration among stakeholders along the value chain of waste, awareness creation on the benefits of composting and addressing challenges faced by both compost producers and users.", keywords = "Composting, emerging city, organic waste management, urban agriculture.", volume = "16", number = "4", pages = "39-9", }
