Cultivation of the Marine Macroalgae Chaetomorpha linum in Municipal Wastewater for Nutrient Recovery and Biomass Production

Due to increasing scarcity of fresh water, use of unconventional water source (e.g., wastewater) in irrigation has now become important. However, inclusive information on the effects of wastewater on crop production and soil health is necessary for such intervention. This study was designed to evaluate these effects by demonstrating the contribution of municipal wastewater (hereafter called wastewater) on yield and nutrient requirement of wheat (<i>Triticum aestivum</i> L.) cv Shatabdi. Five irrigation treatments - I1, I2, I3, I4 and I5 were tested in a Randomized Complete Block Design (RCBD) with three replications during November-March of 2007-2008, 2008-2009, 2009-2010 at the experimental field of the Bangladesh Agricultural University, Mymensingh. The treatments I2-I5 consisted of blended wastewater and I1 of fresh water (control). The ratio of wastewater to total irrigation water was 0.25, 0.50, 0.75 and 1.0 in I2, I3, I4 and I5, respectively. Wheat was cultivated with three irrigations and recommended doses of fertilizer in three consecutive years. Wastewater contained nitrogen (N), phosphorus (P) and potassium (K) @ 17.5, 3.7 and 10.3 mg/L, respectively, and irrigation by raw wastewater (I5) contributed 19.1, 15.1 and 21.7% of the recommended N, P and K, respectively. Biomass yield increased with increasing fraction of wastewater in irrigation. Grain yield increased for the wastewater fraction of 0.50 - 0.75 in irrigation but decreased when irrigation was applied by raw wastewater. Excess fertilizer (under I5) boosted up growth of wheat, but did not contribute to the grain yield. Number of grains per spike; and grain, straw and biological yields significantly (p = 0.05) increased due to the contribution of wastewater. Wastewater significantly improved grain and biomass production, with the largest value obtained in I4 (4.61 t/ha grain yield and 11.36 t/ha biomass yield). Raw wastewater in combination with recommended fertilizer doses caused over-fertilization that contributed only in biomass production but not in grain production of wheat and irrigation by wastewater substantially reduced fertilizer requirement of wheat.The Agriculturists 2016; 14(1) 01-14

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Evaluation of Pilot-Scale Constructed Wetlands with Phragmites karka for Phytoremediation of Municipal Wastewater and Biomass Production in Ethiopia

Environmental Processes ◽

10.1007/s40710-019-00358-x ◽

2019 ◽

Vol 6 (1) ◽

pp. 65-84 ◽

Cited By ~ 4

Author(s):

Kenatu Angassa ◽

Seyoum Leta ◽

Worku Mulat ◽

Helmut Kloos ◽

Erik Meers

Keyword(s):

Constructed Wetlands ◽

Biomass Production ◽

Municipal Wastewater ◽

Pilot Scale ◽

Phragmites Karka

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Enhanced production of biomass and lipids by Euglena gracilis via co-culturing with a microalga growth-promoting bacterium, Emticicia sp. EG3

Biotechnology for Biofuels ◽

10.1186/s13068-019-1544-2 ◽

2019 ◽

Vol 12 (1) ◽

Cited By ~ 2

Author(s):

Tadashi Toyama ◽

Tsubasa Hanaoka ◽

Koji Yamada ◽

Kengo Suzuki ◽

Yasuhiro Tanaka ◽

...

Keyword(s):

Biomass Production ◽

Euglena Gracilis ◽

Culture System ◽

Municipal Wastewater ◽

Wastewater Effluent ◽

Biofuel Production ◽

Second Step ◽

Microalgal Biomass ◽

Enhanced Production ◽

Growth Promoting

Abstract Background Euglena gracilis, a unicellular flagellated microalga, is regarded as one of the most promising species as microalgal feedstock for biofuels. Its lipids (mainly wax esters) are suitable for biodiesel and jet fuel. Culture of E. gracilis using wastewater effluent will improve the economics of E. gracilis biofuel production. Enhancement of the productivity of E. gracilis biomass is critical to creating a highly efficient biofuels production system. Certain bacteria have been found to promote microalgal growth by creating a favorable microenvironment. These bacteria have been characterized as microalgae growth-promoting bacteria (MGPB). Co-culture of microalgae with MGPB might offer an effective strategy to enhance microalgal biomass production in wastewater effluent culture systems. However, no MGPB has been identified to enhance the growth of E. gracilis. The objectives of this study were, therefore, to isolate and characterize the MGPB effective for E. gracilis and to demonstrate that the isolated MGPB indeed enhances the production of biomass and lipids by E. gracilis in wastewater effluent culture system. Results A bacterium, Emticicia sp. EG3, which is capable of promoting the growth of microalga E. gracilis, was isolated from an E. gracilis-municipal wastewater effluent culture. Biomass production rate of E. gracilis was enhanced 3.5-fold and 3.1-fold by EG3 in the co-culture system using a medium of heat-sterilized and non-sterilized wastewater effluent, respectively, compared to growth in the same effluent culture but without EG3. Two-step culture system was examined as follows: E. gracilis was cultured with or without EG3 in wastewater effluent in the first step and was further grown in wastewater effluent in the second step. Production yields of biomass and lipids by E. gracilis were enhanced 3.2-fold and 2.9-fold, respectively, in the second step of the system in which E. gracilis was co-cultured with EG3 in the first step. Conclusion Emticicia sp. EG3 is the first MGPB for E. gracilis. Growth-promoting bacteria such as EG3 will be promising agents for enhancing E. gracilis biomass/biofuel productivities.

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