Rice Cultivation without Synthetic Fertilizers and Performance of Microbial Fuel Cells (MFCs) under Continuous Irrigation with Treated Wastewater

To obtain a high rice yield and quality for animal feed without synthetic fertilizers, an experiment with bench-scale apparatus was conducted by applying continuous irrigation with treated municipal wastewater (TWW). Uniform rice seedlings of a high-yield variety (Oryza sativa L., cv. Bekoaoba) were transplanted in five treatments to examine different TWW irrigation directions (“bottom-to-top” and “top-to-top” irrigation) and fertilization practices (with and without P-synthetic fertilizers) as well as one control that simulated the irrigation and fertilization management of normal paddy fields. The highest rice yield (14.1 t ha−1), shoot dry mass (12.9 t ha−1), and protein content in brown rice (14.6%) were achieved using bottom-to-top irrigation, although synthetic fertilizers were not applied. In addition, this subsurface irrigation system could contribute to environmental protection by removing 85–90% of nitrogen from TWW more effectively than the top-to-top irrigation, which showed a removal efficiency of approximately 63%. No accumulation of heavy metals (Fe, Mn, Cu, Zn, Cd, Ni, Pb, Cr, and As) in the paddy soils was observed after TWW irrigation for five months, and the contents of these metals in the harvested brown rice were lower than the permissible limits recommended by international standards. A microbial fuel cell system (MFC) was installed in the cultivation system using graphite-felt electrodes to test the capacity of electricity generation; however, the electricity output was much lower than that reported in normal paddy fields. Bottom-to-top irrigation with TWW can be considered a potential practice to meet both water and nutrient demand for rice cultivation in order to achieve a very high yield and nutritional quality of cultivated rice without necessitating the application of synthetic fertilizers.

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Bottom-to-top continuous irrigation of treated municipal wastewater for effective nitrogen removal and high quality rice for animal feeding

Water Science & Technology Water Supply ◽

10.2166/ws.2017.190 ◽

2017 ◽

Vol 18 (4) ◽

pp. 1183-1195 ◽

Cited By ~ 3

Author(s):

Dong Duy Pham ◽

Sumiko Kurashima ◽

Nobuo Kaku ◽

Atsushi Sasaki ◽

Jian Pu ◽

...

Keyword(s):

Heavy Metals ◽

Nitrogen Removal ◽

Municipal Wastewater ◽

Animal Feed ◽

Brown Rice ◽

Dry Mass ◽

Continuous Irrigation ◽

Animal Feeding ◽

Treated Municipal Wastewater ◽

Bottom To Top

Abstract A bench-scale experiment to cultivate rice for animal feeding with continuous irrigation of treated municipal wastewater (TWW) in six different conditions was carried out to examine nitrogen removal from TWW, yield and quality of harvested rice, and accumulation of heavy metals in soil and rice grains. A microbial fuel cell (MFC) system comprising graphite felt electrodes was also installed to generate electricity in the paddy field. The highest rice yield (9.0 ton/ha), dry mass (12.4 ton/ha), and protein content (13.1%), an important nutrient in animal feed, were obtained when a bottom-to-top irrigation (TWW was supplied to the underdrain pipe) was applied at the highest flow rate. The bottom-to-top irrigation achieved 79 to 91% removal of nitrogen in TWW, which was much higher than the top-to-top irrigation (58%). No accumulation of heavy metals was found in the experimental soils, and heavy metal concentrations in brown rice were lower than the allowable levels of current standards. The electric output from the MFC system was much lower than that reported in normal paddy fields, probably due to the poor connection between cables and electrodes. Further study is necessary to improve the electricity generation and to continuously monitor heavy metals in brown rice and the soil.

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Methane mitigation is associated with reduced abundance of methanogenic and methanotrophic communities in paddy soils continuously sub-irrigated with treated wastewater

Scientific Reports ◽

10.1038/s41598-021-86925-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Luc Duc Phung ◽

Masaaki Miyazawa ◽

Dung Viet Pham ◽

Masateru Nishiyama ◽

Shuhei Masuda ◽

...

Keyword(s):

Rice Yield ◽

Irrigation System ◽

Wastewater Reuse ◽

Soil Layer ◽

Methanogenic Archaea ◽

Greenhouse Gas Mitigation ◽

Paddy Soils ◽

Paddy Fields ◽

Treated Wastewater ◽

Protein Rich

AbstractHerein, we examined emissions of CH4 and the community structures of methanogenic archaea and methanotrophic bacteria in paddy soils subjected to a novel irrigation system, namely continuous sub-irrigation with treated wastewater (TWW). This system has recently been developed by our group to effectively reuse TWW for the cultivation of protein-rich rice. The results showed that, despite not using mineral fertilisers, the wastewater reuse system produced a rice yield comparable to that of a conventional cultivation practice and reduced CH4 emissions from paddy fields by 80%. Continuous sub-irrigation with TWW significantly inhibited the growth of methanogens in the lower soil layer during the reproductive stage of rice plants, which was strongly consistent with the effective CH4 mitigation, resulting in a vast reduction in the abundance of methanotrophs in the upper soil layer. The compositions of the examined microbial communities were not particularly affected by the studied cultivation practices. Overall, this study demonstrated that continuous sub-irrigation with TWW was an effective method to produce high rice yield and simultaneously reduce CH4 emissions from paddy fields, and it also highlighted the potential underlying microbial mechanisms of the greenhouse gas mitigation.

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Methane Mitigation is Associated with Reduced Abundance of Methanogenic and Methanotrophic Communities in Paddy Soils Continuously Sub-irrigated with Treated Wastewater

10.21203/rs.3.rs-189596/v1 ◽

2021 ◽

Author(s):

Luc Duc Phung ◽

Masaaki Miyazawa ◽

Dung Viet Pham ◽

Masateru Nishiyama ◽

Shuhei Masuda ◽

...

Keyword(s):

Rice Yield ◽

Irrigation System ◽

Wastewater Reuse ◽

Soil Layer ◽

Methanogenic Archaea ◽

Greenhouse Gas Mitigation ◽

Paddy Soils ◽

Paddy Fields ◽

Treated Wastewater ◽

Protein Rich

Abstract Herein, we examined emissions of CH4 and the community structures of methanogenic archaea and methanotrophic bacteria in paddy soils subjected to a novel irrigation system, namely continuous sub-irrigation with treated wastewater (TWW). This system has recently been developed by our group to effectively reuse TWW for the cultivation of protein-rich rice. The results showed that despite not using mineral fertilisers, the wastewater reuse system produced a high rice yield comparable to that of a conventional cultivation practice and reduced CH4 emissions from paddy fields by 80%. During the reproductive stage of rice plants, when high levels of CH4 emissions from both treatments were observed, continuous sub-irrigation with TWW not only considerably inhibited the growth of methanogens in the lower soil layer, but also vastly reduced the abundance of methanotrophs in the upper soil layer, which was strongly consistent with the effective mitigation of CH4. The compositions of the examined microbial communities were not particularly affected by the studied cultivation practices. Overall, this study demonstrated that continuous sub-irrigation with TWW was an effective method to produce high rice yield and simultaneously reduce CH4 emissions from paddy fields, and it also highlighted the potential underlying microbial mechanisms of the greenhouse gas mitigation.

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Impacts of Long- and Short-Term of Irrigation with Treated Wastewater and Synthetic Fertilizers on the Growth, Biomass, Heavy Metal Content, and Energy Traits of Three Potential Bioenergy Crops in Arid Regions

Energies ◽

10.3390/en14113037 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3037

Author(s):

Mahmoud F. Seleiman ◽

Nasser Al-Suhaibani ◽

Salah El-Hendawy ◽

Kamel Abdella ◽

Majed Alotaibi ◽

...

Keyword(s):

Trace Elements ◽

Arid Regions ◽

Biomass Energy ◽

Recommended Dose ◽

Treated Wastewater ◽

Bioenergy Crops ◽

Virgin Soil ◽

Field Crops ◽

Synthetic Fertilizers ◽

The Impact

The availability of suitable water is an important factor for increasing the cultivated areas and sustainability in arid (i.e., less than 200 mm precipitation per year) and semiarid regions (i.e., 200–700 mm precipitation per year). Therefore, this study aimed to analyze the impact of treated wastewater (TWW) and groundwater (GW) as well as synthetic fertilizers (50% and 100% of the recommended NPK dose; 150–150–60 kg N–P2O5–K2O ha−1) on the growth, biomass, energy traits, and macro and trace elements of maize (Zea mays L.), sorghum (Sorghum bicolor L.), and pearl millet (Pennisetum glaucum L) grown in old cultivated (first location; L1) and virgin soil (L2 and L3) as potential bioenergy crops. The soil in L1 has been irrigated with treated wastewater for the last 15 years and continued to be irrigated with treated wastewater in this investigation. The virgin soil was divided into two parts: the first part was irrigated with TWW, and the second part was irrigated with GW. The experiments were laid out in a split-plot with a randomized complete block design with water treatments (TWW in old and virgin soil, and GW in virgin soil) in main plots, and the two treatments of fertilization (50% and 100% of the recommended NPK dose) were distributed randomly in subplots. Compared with the crops irrigated with GW, the crops irrigated with TWW, whether grown on old or virgin soil, showed higher plant height, total chlorophyll content, leaf area per plant, total biomass, energy content, and gross energy with low ash. They also contained higher (but lower than permissible limits) concentrations of macro-elements (NPK) and trace elements (Fe, Mn, Cu, Zn, Cd, Pb, Ni, and Co). In addition, the application of a 50% recommended dose of NPK with TWW showed equivalent results to a 100% recommended dose of NPK on all measured parameters with few exceptions. In conclusion, the TWW can be used to irrigate field crops allocated for bioenergy production in arid regions because it does not harm the plants and environment. In addition, the 50% recommended dose of NPK fertilizer exerted no negative effects on the growth and energy production of field crops, thereby protecting the environment and reducing the leaching of excessive fertilizers into GW.

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Cultivation of rice for animal feed with circulated irrigation of treated municipal wastewater for enhanced nitrogen removal: comparison of cultivation systems feeding irrigation water upward and downward

Water Science & Technology ◽

10.2166/wst.2015.251 ◽

2015 ◽

Vol 72 (4) ◽

pp. 579-584 ◽

Cited By ~ 7

Author(s):

A. Muramatsu ◽

H. Ito ◽

A. Sasaki ◽

A. Kajihara ◽

T. Watanabe

Keyword(s):

Nitrogen Removal ◽

Irrigation Water ◽

Rice Plant ◽

Municipal Wastewater ◽

Animal Feed ◽

Paddy Fields ◽

Treated Wastewater ◽

Human Consumption ◽

Cultivation System ◽

Treated Municipal Wastewater

To achieve enhanced nitrogen removal, we modified a cultivation system with circulated irrigation of treated municipal wastewater by using rice for animal feed instead of human consumption. The performance of this modified system was evaluated through a bench-scale experiment by comparing the direction of circulated irrigation (i.e. passing through paddy soil upward and downward). The modified system achieved more than three times higher nitrogen removal (3.2 g) than the system in which rice for human consumption was cultivated. The removal efficiency was higher than 99.5%, regardless of the direction of circulated irrigation. Nitrogen in the treated municipal wastewater was adsorbed by the rice plant in this cultivation system as effectively as chemical fertilizer used in normal paddy fields. Circulated irrigation increased the nitrogen released to the atmosphere, probably due to enhanced denitrification. Neither the circulation of irrigation water nor its direction affected the growth of the rice plant and the yield and quality of harvested rice. The yield of rice harvested in this system did not reach the target value in normal paddy fields. To increase this yield, a larger amount of treated wastewater should be applied to the system, considering the significant amount of nitrogen released to the atmosphere.

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Resource-Saving Rice Cultivation with Circulated Irrigation of Treated Wastewater

Journal of Japan Society of Civil Engineers Ser G (Environmental Research) ◽

10.2208/jscejer.68.iii_93 ◽

2012 ◽

Vol 68 (7) ◽

pp. III_93-III_101

Author(s):

Ayumi MURAMATSU ◽

Toru WATANABE ◽

Atsushi SASAKI ◽

Hiroaki ITO ◽

Akihiko KAJIHARA

Keyword(s):

Rice Cultivation ◽

Treated Wastewater ◽

Resource Saving

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Effects of Biochar Amendment on CO2 Emissions from Paddy Fields under Water-Saving Irrigation

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15112580 ◽

2018 ◽

Vol 15 (11) ◽

pp. 2580 ◽

Cited By ~ 4

Author(s):

Shihong Yang ◽

Zewei Jiang ◽

Xiao Sun ◽

Jie Ding ◽

Junzeng Xu

Keyword(s):

Co2 Emissions ◽

Rice Yield ◽

Rice Paddy ◽

C Sequestration ◽

Sensitivity Coefficient ◽

Water Saving ◽

Paddy Fields ◽

Flood Irrigation ◽

Controlled Irrigation ◽

Biochar Amendment

The role of carbon pool of biochar as a method of long-term C sequestration in global warming mitigation is unclear. A two-year field study was conducted to investigate the seasonal variations of CO2 emissions from water-saving irrigation paddy fields in response to biochar amendment and irrigation patterns. Three biochar treatments under water-saving irrigation and one biochar treatment under flooding irrigation were studied, and the application rates were 0, 20, 40, and 40 t ha−1 and labeled as CI + NB (controlled irrigation and none biochar added), CI + MB (controlled irrigation and medium biochar added), CI + HB (controlled irrigation and high biochar added), and FI + HB (flood irrigation and high biochar added), respectively. Results showed that biochar application at medium rates (20 t ha−1) decreased CO2 emissions by 1.64–8.83% in rice paddy fields under water-saving irrigation, compared with the non-amendment treatment. However, the CO2 emissions from paddy fields increased by 4.39–5.43% in the CI + HB treatment, compared with CI + NB. Furthermore, the mean CO2 emissions from paddy fields under water-saving irrigation decreased by 2.22% compared with flood irrigation under the same amount of biochar application (40 t ha−1). Biochar amendment increased rice yield and water use efficiency by 9.35–36.30% and 15.1–42.5%, respectively, when combined with water-saving irrigation. The CO2 emissions were reduced in the CI + MB treatment, which then increased rice yield. The CO2 emissions from paddy fields were positively correlated with temperature. The highest value of the temperature sensitivity coefficient (Q10) was derived for the CI + MB treatment. The Q10 was higher under water-saving irrigation compared with flooding irrigation.

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Intra- versus inter-site macroscale variation in biogeochemical properties along a paddy soil chronosequence

Biogeosciences ◽

10.5194/bg-9-1237-2012 ◽

2012 ◽

Vol 9 (3) ◽

pp. 1237-1251 ◽

Cited By ~ 17

Author(s):

C. Mueller-Niggemann ◽

A. Bannert ◽

M. Schloter ◽

E. Lehndorff ◽

L. Schwark

Keyword(s):

Paddy Soil ◽

Tidal Flat ◽

Land Reclamation ◽

Zhejiang Province ◽

Rice Cultivation ◽

Carbon Accumulation ◽

Paddy Soils ◽

Paddy Fields ◽

Wetland Rice ◽

Tidal Wetland

Abstract. In order to assess the intrinsic heterogeneity of paddy soils, a set of biogeochemical soil parameters was investigated in five field replicates of seven paddy fields (50, 100, 300, 500, 700, 1000, and 2000 yr of wetland rice cultivation), one flooded paddy nursery, one tidal wetland (TW), and one freshwater site (FW) from a coastal area at Hangzhou Bay, Zhejiang Province, China. All soils evolved from a marine tidal flat substrate due to land reclamation. The biogeochemical parameters based on their properties were differentiated into (i) a group behaving conservatively (TC, TOC, TN, TS, magnetic susceptibility, soil lightness and colour parameters, δ13C, δ15N, lipids and n-alkanes) and (ii) one encompassing more labile properties or fast cycling components (Nmic, Cmic, nitrate, ammonium, DON and DOC). The macroscale heterogeneity in paddy soils was assessed by evaluating intra- versus inter-site spatial variability of biogeochemical properties using statistical data analysis (descriptive, explorative and non-parametric). Results show that the intrinsic heterogeneity of paddy soil organic and minerogenic components per field is smaller than between study sites. The coefficient of variation (CV) values of conservative parameters varied in a low range (10% to 20%), decreasing from younger towards older paddy soils. This indicates a declining variability of soil biogeochemical properties in longer used cropping sites according to progress in soil evolution. A generally higher variation of CV values (>20–40%) observed for labile parameters implies a need for substantially higher sampling frequency when investigating these as compared to more conservative parameters. Since the representativeness of the sampling strategy could be sufficiently demonstrated, an investigation of long-term carbon accumulation/sequestration trends in topsoils of the 2000 yr paddy chronosequence under wetland rice cultivation restricted was conducted. Observations cannot be extrapolated to global scale but with coastal paddy fields developed on marine tidal flat substrates after land reclamation in the Zhejiang Province represent a small fraction (<1%) of the total rice cropping area. The evolutionary trend showed that the biogeochemical signatures characteristic for paddy soils were fully developed in less than 300 yr since onset of wetland rice cultivation. A six-fold increase of topsoil TOC suggests a substantial gain in CO2 sequestration potential when marine tidal wetland substrate developed to 2000 yr old paddy soil.

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Ameliorasi Berbasis Unsur Hara Silika di Lahan Rawa

Jurnal Sumberdaya Lahan ◽

10.21082/jsdl.v14n1.2020.37-47 ◽

2020 ◽

Vol 14 (1) ◽

pp. 37

Author(s):

Adha Siregar ◽

Wahida Annisa

Keyword(s):

Soil Acidity ◽

Root Zone ◽

Rice Yield ◽

Al Toxicity ◽

Rice Cultivation ◽

Limiting Factors ◽

Fe Uptake ◽

Enormous Amount ◽

Toxicity Level ◽

Fe Toxicity

Abstrak. Unsur hara Silika (Si) memiliki peranan penting pada pertumbuhan dan produktivitas tanaman padi. Tanaman padi menyerap Si dalam jumlah yang besar yaitu sekitar 10 kali N, 20 kali P, 6 kali K dan 30 kali Ca. Budidaya padi di lahan rawa memiliki beberapa faktor pembatas yang mempengaruhi pertumbuhan dan produktivitas padi diantaranya keracunan unsur toksik seperti Fe dan Al. Kadar unsur toksik terutama Fe di lahan rawa menyebabkan tanah menjadi masam, sehingga banyak tanaman yang tidak dapat beradaptasi dengan kondisi tersebut. Kondisi ini dapat diatasi diantaranya dengan aplikasi Si, yang berperan menurunkan serapan Fe dan Al yang berada dalam kondisi toksik. Beberapa hasil penelitian menunjukkan bahwa Si berpengaruh dalam menurunkan tingkat toksisitas Al dan Fe di tanah. Aplikasi Si sebagai amelioran mengurangi kandungan Fe pada permukaan akar padi serta menurunkan serapan Fe pada tanaman padi sawah melalui peningkatan kekuatan oksidasi akar. Lebih lanjut, aplikasi Si pada budidaya tanaman padi dapat meningkatkan hasil gabah sebesar 50,8%. Abtract. Silicon (Si) has an important role on rice crops growth and productivity. Rice crops absorbs enormous amount of Si as much as ten times of N, twenty times of P, six times of K and thirty times of Ca. Rice cultivation in swampland has several limiting factors such as Fe and Al toxicity. Fe toxicity could increase soil acidity in swampland. However, most plants could not adapt to this condition. Si application as soil ameliorant could be an option to overcome this problem. Si could reduce the toxicity level of Fe and Mn in soil. Previous research proved that Si could decrease Fe and Al toxicity. Si application as ameliorant could reduce Fe concentration in root zone which lead to decreasing Fe uptake through increasing oxidation capability of the root. Moreover, Si application could increase rice yield up to 50.8%..

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WATER MANAGEMENT AND METHANE EMISSION FROM RICE CULTIVATION: A CASE STUDY IN AN GIANG PROVINCE, VIET NAM

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/54/2a/11916 ◽

2018 ◽

Vol 54 (2A) ◽

pp. 91

Author(s):

Duong Mai Linh

Keyword(s):

Water Management ◽

Global Warming ◽

Rice Yield ◽

Soil Surface ◽

Water Levels ◽

Rice Cultivation ◽

Viet Nam ◽

Ch4 Emission ◽

Wetting And Drying

Rice cultivation causes the emission of CH4 consequenced to the global warming. Reduction of irrigation in rice cultivation is not only saving water resources but also reducing greenhouse gases emission. The objectives of this study was to determine impacts of water management on the emission of CH4 and rice yield. Experiment was conducted in field conditions in An Giang province, Viet Nam with three treatments as continuous flooding (CF), An Giang Alternative Wetting and Drying (AAWD) which is mostly applied by farmers in An Giang province-Viet Nam, and Alternate Wetting and Drying (AWD). Water levels in the field +5 cm, ± 5 cm and -15 cm were controlled higher, fluctuated and lower than soil surface, respectively for CF, AAWD and AWD. CH4 emission determined every week during 13 weeks of the experiment. Rice yield was determined in 1 m2 at the end of the experiment. The results showed that AWD and AAWD, respectively decreased 78.7 % (p < 0.05) and 6.8 % (p > 0.05) CH4 emission compared to the CF 11.9 mg CH4/m2/h. The rice yield of CF was 6.32 ton/ha lower than AAWD 7.8 ton/ha (p < 0.05) but not different with AWD 6.67 ton/ha. AAWD had higher rice yield but same emission than the CF. Farmers in An Giang province should consider application of AWD in rice cultivation in term of saving water and reduction of CH4 emission.

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