Rice straw biochar affects water retention and air movement in a sand-textured tropical soil

DEFF Research Database (Denmark)

Arthur, Emmanuel; Ahmed, Fauziatu

2017-01-01

Despite the current global attention on biochar (BC) as a soil amendment, knowledge is limited on how BC impacts the physical properties of coarse-textured soils (sand > 95%), particularly in tropical regions. A two-season field-study was conducted to investigate the effect of rice straw BC (3% w...

Microbial utilization of rice straw and its derived biochar in a paddy soil

Energy Technology Data Exchange (ETDEWEB)

Pan, Fuxia [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Ningbo Urban Environment Observation and Research Station-NUEORS, Chinese Academy of Sciences, Ningbo 315800 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Li, Yaying [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Ningbo Urban Environment Observation and Research Station-NUEORS, Chinese Academy of Sciences, Ningbo 315800 (China); Chapman, Stephen James [The James Hutton Institute, Craigiebuckler, Aberdeen AB15 8QH (United Kingdom); Khan, Sardar [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Department of Environmental Science, University of Peshawar (Pakistan); Yao, Huaiying, E-mail: hyyao@iue.ac.cn [Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021 (China); Ningbo Urban Environment Observation and Research Station-NUEORS, Chinese Academy of Sciences, Ningbo 315800 (China)

2016-07-15

The application of straw and biochar to soil has received great attention because of their potential benefits such as fertility improvement and carbon (C) sequestration. The abiotic effects of these materials on C and nitrogen (N) cycling in the soil ecosystem have been previously investigated, however, the effects of straw or its derived biochar on the soil microbial community structure and function are not well understood. For this purpose, a short-term incubation experiment was conducted using {sup 13}C-labeled rice straw and its derived biochar ({sup 13}C-labeled biochar) to deepen our understanding about soil microbial community dynamics and function in C sequestration and greenhouse gas emission in the acidic paddy soil amended with these materials. Regarding microbial function, biochar and straw applications increased CO{sub 2} emission in the initial stage of incubation and reached the highest level (0.52 and 3.96 mg C kg{sup −1} soil h{sup −1}) at 1 d and 3 d after incubation, respectively. Straw amendment significantly (p < 0.01) increased respiration rate, total phospholipid fatty acids (PLFAs) and {sup 13}C-PLFA as compared to biochar amendment and the control. The amount and percent of Gram positive bacteria, fungi and actinomycetes were also significantly (p < 0.05) higher in {sup 13}C-labeled straw amended soil than the {sup 13}C-labeled biochar amended soil. According to the {sup 13}C data, 23 different PLFAs were derived from straw amended paddy soil, while only 17 PLFAs were derived from biochar amendments. The profile of {sup 13}C-PLFAs derived from straw amendment was significantly (p < 0.01) different from biochar amendment. The PLFAs 18:1ω7c and cy17:0 (indicators of Gram negative bacteria) showed high relative abundances in the biochar amendment, while 10Me18:0, i17:0 and 18:2ω6,9c (indicators of actinomycetes, Gram positive bacteria and fungi, respectively) showed high relative abundance in the straw amendments. Our results suggest

Bioethanol production from rice straw residues

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Elsayed B. Belal

2013-01-01

Full Text Available A rice straw -cellulose utilizing mold was isolated from rotted rice straw residues. The efficient rice straw degrading microorganism was identified as Trichoderma reesei. The results showed that different carbon sources in liquid culture such as rice straw, carboxymethyl cellulose, filter paper, sugar cane bagasse, cotton stalk and banana stalk induced T. reesei cellulase production whereas glucose or Potato Dextrose repressed the synthesis of cellulase. T. reesei cellulase was produced by the solid state culture on rice straw medium. The optimal pH and temperature for T. reesei cellulase production were 6 and 25 ºC, respectively. Rice straw exhibited different susceptibilities towards cellulase to their conversion to reducing sugars. The present study showed also that, the general trend of rice straw bioconversion with cellulase was more than the general trend by T. reesei. This enzyme effectively led to enzymatic conversion of acid, alkali and ultrasonic pretreated cellulose from rice straw into glucose, followed by fermentation into ethanol. The combined method of acid pretreatment with ultrasound and subsequent enzyme treatment resulted the highest conversion of lignocellulose in rice straw to sugar and consequently, highest ethanol concentration after 7 days fermentation with S. cerevisae yeast. The ethanol yield in this study was about 10 and 11 g.L-1.

Polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like polychlorinated biphenyls in rice straw smoke and their origins in Japan.

Science.gov (United States)

Minomo, Kotaro; Ohtsuka, Nobutoshi; Nojiri, Kiyoshi; Hosono, Shigeo; Kawamura, Kiyoshi

2011-08-01

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (DL-PCBs) contained in the smoke generated from rice straw burning in post-harvest paddy fields in Japan were analyzed to determine their congener profiles. Both the apportionment of toxic equivalent (TEQ) by using indicative congeners and the comparison of the homolog profiles showed that the PCDDs/PCDFs/DL-PCBs present in the rice-straw smoke were greatly influenced by those present as impurities in pentachlorophenol (PCP) and chlornitrofen (CNP, 4-nitrophenyl-2,4,6-trichlorophenyl ether) formulations that had been widely used as herbicides in paddy fields in Japan. Further, in order to investigate the effects of paddy-field soil on the PCDDs/PCDFs/DL-PCBs present in rice-straw smoke, PCDD/PCDF/DL-PCB homolog profiles of rice straw, rice-straw smoke and paddy-field soil were compared. Rice-straw smoke was generated by burning rice straw on a stainless-steel tray in a laboratory. The results suggested that the herbicides-originated PCDDs/PCDFs/DL-PCBs and the atmospheric PCDDs/PCDFs/DL-PCBs contributed predominantly to the presence of PCDDs/PCDFs/DL-PCBs in the rice-straw smoke while the contribution of PCDDs/PCDFs/DL-PCBs formed during rice straw burning was relatively minimal. The major sources of the PCDDs/PCDFs/DL-PCBs found in the rice-straw smoke were attributed primarily to the paddy-field soil adhered to the rice straw surface and secondarily to the air taken by the rice straw. The principal component analysis supported these conclusions. It is concluded that rice straw burning at paddy fields acts as a driving force in the transfer of PCDDs/PCDFs/DL-PCBs from paddy-field soil to the atmosphere. Copyright © 2011 Elsevier Ltd. All rights reserved.

Variations in the patterns of soil organic carbon mineralization and microbial communities in response to exogenous application of rice straw and calcium carbonate

International Nuclear Information System (INIS)

Feng, Shuzhen; Huang, Yuan; Ge, Yunhui; Su, Yirong; Xu, Xinwen; Wang, Yongdong; He, Xunyang

2016-01-01

The addition of exogenous inorganic carbon (CaCO 3 ) and organic carbon has an important influence on soil organic carbon (SOC) mineralization in karst soil, but the microbial mechanisms underlying the SOC priming effect are poorly understood. We conducted a 100-day incubation experiment involving four treatments of the calcareous soil in southwestern China's karst region: control, 14 C-labeled rice straw addition, 14 C-labeled CaCO 3 addition, and a combination of 14 C-labeled rice straw and CaCO 3 . Changes in soil microbial communities were characterized using denaturing gradient gel electrophoresis with polymerase chain reaction (PCR-DGGE) and real-time quantitative PCR (q-PCR). Both 14 C-rice straw and Ca 14 CO 3 addition stimulated SOC mineralization, suggesting that organic and inorganic C affected SOC stability. Addition of straw alone had no significant effect on bacterial diversity; however, when the straw was added in combination with calcium carbonate, it had an inhibitory effect on bacterial and fungal diversity. At the beginning of the experimental period, exogenous additives increased bacterial abundance, although at the end of the 100-day incubation bacterial community abundance had gradually declined. Incubation time, exogenous input, and their interaction significantly affected SOC mineralization (in terms of priming and the cumulative amount of mineralization), microbial biomass carbon (MBC), and microbial community abundance and diversity. Moreover, the key factors influencing SOC mineralization were MBC, bacterial diversity, and soil pH. Overall, these findings support the view that inorganic C is involved in soil C turnover with the participation of soil microbial communities, promoting soil C cycling in the karst region. - Highlights: • Different patterns of 14 C-rice straw and Ca 14 CO 3 addition on positive priming effects of SOC mineralization. • Inorganic C is involved in soil C cycling with the participation of soil microbial

IMPACT OF BRACHIARIA, ARBUSCULAR MYCORRHIZA, AND POTASSIUM ENRICHED RICE STRAW COMPOST ON ALUMINIUM, POTASSIUM AND STABILITY OF ACID SOIL AGGREGATES

Directory of Open Access Journals (Sweden)

Bariot Hafif

2013-04-01

Full Text Available Acid soil is commonly grown with cassava, which in general, tolerate low soil  fertility and aluminum (Al toxicity. However, without any improvement efforts such soil will become worse. Intercropping cassava with Brachiaria decumbens (BD which adapts to acid soil and tolerates low fertility soils as well as application of arbuscular mycorrhiza (AM and organic matters are among the important efforts to rehabilitate this soil. The experiment was conducted to  examine the impact of BD, AM, and potassium (K enriched rice straw compost on exchangeable Al, available K, and stability of soil aggregates. Experiment was arranged in a completely randomized design with three factors and three replications. The first factor was BD as cassava intercropping, the second factor was AM, and the third factor was 2 t ha-1 rice straw compost enriched with 0 kg, 50 kg, 100 kg, and 200 kg KCl ha-1. Brick pots (1 m length x 1 m width x 0.45 m depth filled with Kanhapludult soil was used for growing cassava in which row of BD was planted at 60 cm from cassava stem. K-enriched rice straw compost and AM (10 g per stem were applied around cassava stem at 2 and 12 days after planting, respectively. BD was cut every 30 days and the cutting was returned to the soil. Soil exchangeable Al was analyzed at 0, 3, 6 and 9 months after planting (MAP, while Al and K contents as well as aggregate stability were measured at 6 MAP. The results showed that planting BD decreased 33% exchangeable Al, which means that the root exudates of this grass was effective in detoxifying Al3+. Treatment of BD and/or in combination with AM was effective in preserving K added to the soil, increasing total polysaccharides, and improving soil aggregate stability. This indicated that planting BD and applying AM and Kenriched rice straw compost improved acid soil fertility, and therefore can be recommended in cassava cultivation.

Enzymatic hydrolsis of pretreated rice straw

Energy Technology Data Exchange (ETDEWEB)

Vlasenko, E.Y.; Shoemaker, S.P. [California Inst. of Food and Agricultural Research, Davis, CA (United States); Ding, H. [California Univ., Davis (Canada). Dept. of Food Science and Technology; Labavitch, J.M. [California Univ., Davis, CA (United States). Dept. of Pomology

1997-02-01

California rice straw is being evaluated as a feedstock for production of power and fuel. This paper examines the initial steps in the process: pretreatment of rice straw and enzymatic hydrolysis of the polysaccharides in the pretreated material to soluble sugars. Rice straw was subjected to three distinct pretreatment procedures: acid-catalyzed steam explosion (Swan Biomass Company), acid hydrolysis (U.S. DOE National Renewable Energy Laboratory), and ammonia fiber explosion or AFEX (Texas A and M University). Standard conditions for each pretreatment were used, but none was optimized for rice straw specifically. Six commercial cellulases, products of Genencor International (USA), Novo (Denmark), Iogen (Canada) and Fermtech (Russia) were used for hydrolysis. The Swan- and the acid-pretreatments effectively removed hemicellulose from rice straw, providing high yields of fermentable sugars. The AFEX-pretreatment was distinctly different from other pretreatments in that it did not significantly solubilize hemicellulose. All three pretreatment procedures substantially increased enzymatic digestibility of rice straw. Three commercial Trichoderma-reesei-derived enzyme preparations: Cellulase 100L (Iogen), Spezyme CP (Genencor), and Al (Fermtech), were more active on pretreated rice straw compared than others tested. Conditions for hydrolysis of rice straw using Cellulase 100L were evaluated. The supplementation of this enzyme preparation with cellobiase (Novozyme 188) significantly improved the parameters of hydrolysis for the Swan- and the acid-pretreated materials, but did not affect the hydrolysis of the AFEX-pretreated rice straw. (Author)

Effects of Crop Straw Returning with Lime on Activity of Cu, Zn, Pb and Cd in Paddy Soil

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NI Zhong-ying

2017-05-01

Full Text Available Crop straw returning is an important measure for increasing soil carbon fixation and soil fertility in China, but it also may result in some risk of raising activity of heavy metals in the soil. In order to understand the effects of different sources of crop straw on heavy metals activity in soil with different pollution levels, and to take appropriate measures to prevent the activation of heavy metals in the soil, both pot and field experiments were carried out to study the effects of crop straw returning with lime on activity of Cu, Zn, Pb and Cd in paddy soil. The experiments were carried out in the soils with both light and heavy pollution of heavy metals. In the pot experiment, three straws, including rice straw with heavy pollution of heavy metals, rice straw with light pollution of heavy metals, and rape straw with light pollution of heavy metals, were tested. Two dosages of lime(0 kg·hm-2 and 750 kg·hm-2were applied. Field experiment had three treatments, ie., control without application of straw and lime, straw returning and straw returning + lime. Soil available heavy metals, accumulation of heavy metals in rice grain, and chemical forms of soil heavy metals were dynamical monitored. The results showed that crop straw returning increased significantly the concentrations of dissolved organic carbon and water soluble heavy metals in paddy soils at the early stage of experiment (in first 20 days. The increase in water soluble heavy metals in the soil with heavy pollution of heavy metals was most obvious as compared with the control treatment. After 60th day of the experiment, the effects of straw returning on the activity of heavy metals in the soil decreased gradually with the time, and became no obvious. The concentrations of water soluble heavy metals in the soil treated with rape straw was generally lower than that of rice straw, while those in the soil treated with heavy pollution of rice straw was higher than low pollution of rice

[Effects of Phosphate Rock and Decomposed Rice Straw Application on Lead Immobilization in a Contaminated Soil].

Science.gov (United States)

Tang, Fan; Hu, Hong-qing; Su, Xiao-juan; Fu, Qing-ling; Zhu, Jun

2015-08-01

The soils treated with phosphate rock (PR) and oxalic acid activated phosphate rock (APR) mixed with decomposed rice straw were incubated in different moisture conditions for 60 days to study the effect on the basic property of the soil and on the speciation variation of Pb. The results showed that all these three types of immobilizing materials increased the pH, the Olsen-P, the exchangeable Ca and the soil cation exchange capacity, and APR showed more obvious effect; the pH and the exchangeable Ca of soil in the flooding treatment were higher than those in normal water treatment (70%), but the Olsen-P of soil in normal water treatment was a little bit more. These materials reduced exchangeable Ph fraction, and converted it into unavailable fraction. But the APR was better than raw PR in immobilizing lead, and the exchangeable Pb fraction was reduced by 40.3% and 24.2%, compared with the control, respectively, and the immobilization effect was positively correlated with the dosage. Decomposed rice straw could transform the exchangeable Ph fraction in soil into organic-bound fraction, while the flooding treatment changed it into the Fe-Mn oxide-bound and residue fractions.

Decomposition of Rice Straw and Corn Straw Under Aerobic and Anaerobic Conditions

Directory of Open Access Journals (Sweden)

WANG Jing

2017-01-01

Full Text Available Decomposition dynamics of rice straw and corn straw at aerobic and anaerobic condition were investigated under the simulated condition in the lab. Results showed that two stages, i.e. the rapid decomposition stage from 0 to 3 months, and the slow one between 3 and 12 months, of decomposition dynamics of rice straw and corn straw were found under anaerobic and aerobic incubation condition, and more than 55%of rice straw and corn mass was lost at the initial 3 months incubation period. The half times(t1/2of rice straw and corn straw mass lost under aerobic condition were 59.2 d and 52.9 d, which were short than those(72.6 d and 79.9 dunder the anaerobic condition, respectively. Carbon release constants from rice straw and corn straw under aerobic condition were 0.61 and 0.60 per month, which were higher than those (0.55 and 0.57 per monthunder anaerobic condition. The nitrogen release from crop straw followed the same rule as the carbon release from straw. The constants of nitrogen released from rice straw and corn straw under aerobic condition were 0.25 and 2.36 per month, which were higher than those(0.16 and 2.32 per monthunder anaerobic condition. The losses of cellulose, hemicelluloses and lignin from rice straw and corn straw under aerobic condition were also higher than those under anaerobic condition. In summary, the aerobic environment increases de composition and release of organic and inorganic substances from crop straw.

Energy and environmental impact analysis of rice cultivation and straw management in northern Thailand.

Science.gov (United States)

Yodkhum, Sanwasan; Sampattagul, Sate; Gheewala, Shabbir H

2018-04-17

Rice cultivation and energy use for rice production can produce the environmental impacts, especially related to greenhouse gas (GHG) emissions. Also, rice straw open burning by farmers generally practiced after harvesting stage in Thailand for removing the residues in the rice field is associated with emissions of air pollutants, especially particulate matter formation that affects human health and global climate. This study assessed the environmental burdens, consisting of GHG emissions, energy use, and particulate matter formation (PM10), from rice cultivation in Thailand by life cycle assessment (LCA) and compared the environmental burdens of rice straw management scenarios: open burning, incorporation into soil, and direct combustion for electricity generation. The data were collected from the rice production cooperative in Chiang Mai province, northern Thailand, via onsite records and face-to-face questionnaires in 2016. The environmental impacts were evaluated from cradle-to-farm gate. The results showed that the total GHG emissions were 0.64 kg CO 2 -eq per kilogram of paddy rice, the total energy use was 1.80 MJ per kilogram of paddy rice and the PM10 emissions were 0.42 g PM10-eq per kilogram of paddy rice. The results of rice straw management scenarios showed that rice straw open burning had the highest GHG and PM10 emissions. However, rice straw utilization by incorporation into soil and direct combustion for electricity generation could reduce these impacts substantially.

Variations in the patterns of soil organic carbon mineralization and microbial communities in response to exogenous application of rice straw and calcium carbonate

Energy Technology Data Exchange (ETDEWEB)

Feng, Shuzhen [Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125 (China); University of Chinese Academy of Sciences, Beijing 100039 (China); Huanjiang Observation and Research Station for Karst Ecosystems, Chinese Academy of Sciences, Huangjiang 547100 (China); Huang, Yuan [Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125 (China); University of Chinese Academy of Sciences, Beijing 100039 (China); Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011 (China); Ge, Yunhui [Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125 (China); College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128 (China); Su, Yirong [Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125 (China); Huanjiang Observation and Research Station for Karst Ecosystems, Chinese Academy of Sciences, Huangjiang 547100 (China); Xu, Xinwen; Wang, Yongdong [Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011 (China); He, Xunyang, E-mail: hbhpjhn@isa.ac.cn [Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125 (China); Huanjiang Observation and Research Station for Karst Ecosystems, Chinese Academy of Sciences, Huangjiang 547100 (China)

2016-11-15

The addition of exogenous inorganic carbon (CaCO{sub 3}) and organic carbon has an important influence on soil organic carbon (SOC) mineralization in karst soil, but the microbial mechanisms underlying the SOC priming effect are poorly understood. We conducted a 100-day incubation experiment involving four treatments of the calcareous soil in southwestern China's karst region: control, {sup 14}C-labeled rice straw addition, {sup 14}C-labeled CaCO{sub 3} addition, and a combination of {sup 14}C-labeled rice straw and CaCO{sub 3}. Changes in soil microbial communities were characterized using denaturing gradient gel electrophoresis with polymerase chain reaction (PCR-DGGE) and real-time quantitative PCR (q-PCR). Both {sup 14}C-rice straw and Ca{sup 14}CO{sub 3} addition stimulated SOC mineralization, suggesting that organic and inorganic C affected SOC stability. Addition of straw alone had no significant effect on bacterial diversity; however, when the straw was added in combination with calcium carbonate, it had an inhibitory effect on bacterial and fungal diversity. At the beginning of the experimental period, exogenous additives increased bacterial abundance, although at the end of the 100-day incubation bacterial community abundance had gradually declined. Incubation time, exogenous input, and their interaction significantly affected SOC mineralization (in terms of priming and the cumulative amount of mineralization), microbial biomass carbon (MBC), and microbial community abundance and diversity. Moreover, the key factors influencing SOC mineralization were MBC, bacterial diversity, and soil pH. Overall, these findings support the view that inorganic C is involved in soil C turnover with the participation of soil microbial communities, promoting soil C cycling in the karst region. - Highlights: • Different patterns of {sup 14}C-rice straw and Ca{sup 14}CO{sub 3} addition on positive priming effects of SOC mineralization. • Inorganic C is involved in

Effect of nitrogen fertilizer and/or rice straw amendment on methanogenic archaeal communities and methane production from a rice paddy soil.

Science.gov (United States)

Bao, Qiongli; Huang, Yizong; Wang, Fenghua; Nie, Sanan; Nicol, Graeme W; Yao, Huaiying; Ding, Longjun

2016-07-01

Nitrogen fertilization and returning straw to paddy soil are important factors that regulate CH4 production. To evaluate the effect of rice straw and/or nitrate amendment on methanogens, a paddy soil was anaerobically incubated for 40 days. The results indicated that while straw addition increased CH4 production and the abundances of mcrA genes and their transcripts, nitrate amendment showed inhibitory effects on them. The terminal restriction fragment length polymorphism (T-RFLP) analysis based on mcrA gene revealed that straw addition obviously changed methanogenic community structure. Based on mcrA gene level, straw-alone addition stimulated Methanosarcinaceaes at the early stage of incubation (first 11 days), but nitrate showed inhibitory effect. The relative abundance of Methanobacteriaceae was also stimulated by straw addition during the first 11 days. Furthermore, Methanosaetaceae were enriched by nitrate-alone addition after 11 days, while Methanocellaceae were enriched by nitrate addition especially within the first 5 days. The transcriptional methanogenic community indicated more dynamic and complicated responses to straw and/or nitrate addition. Based on mcrA transcript level, nitrate addition alone resulted in the increase of Methanocellaceae and the shift from Methanosarcinaceae to Methanosaetaceae during the first 5 days of incubation. Straw treatments increased the relative abundance of Methanobacteriaceae after 11 days. These results demonstrate that nitrate addition influences methanogens which are transcriptionally and functionally active and can alleviate CH4 production associated with straw amendment in paddy soil incubations, presumably through competition for common substrates between nitrate-utilizing organisms and methanogens.

Production and uses of 14C-labelled rice straw in organic matter decomposition studies

International Nuclear Information System (INIS)

Capistrano, R.F.; Neue, H.N.U.

1987-01-01

A new systematic procedure in labeling rice homogenously with 14 CO 2 to maturity is described. It uses a modified plant growth chamber equipped with provisions for the growth requirements of rice as well as, the decontamination and safety aspects of labeling process. Uses of 14 C-labeled rice straw are described. Sample preparation using a new wet combustion set-up a high vacuum preparation line, concomitant with instruments as liquid scintillation counter, vibrating reed electrometer and radiogaschromatograph is also discussed. The turnover and behavior of 14 C-labeled rice straw in organic matter decomposition experiments on wetland soils, upland soils, greenhouse set-up and controlled laboratory conditions are concurrent researches that make use of the produced 14 C-labeled straw. Initial results are discussed. (Auth.) 16 refs.; 14 figs.; 2 tabs

Rice straw as a feedstock for biofuels: Availability, recalcitrance, and chemical properties: Rice straw as a feedstock for biofuels

Energy Technology Data Exchange (ETDEWEB)

Satlewal, Alok [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemical and Biomolecular Engineering; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Joint Inst. for Biological Sciences, Biosciences Division; Indian Oil Corporation Ltd, Faridabad (India), Dept. of Bioenergy, DBT-IOC Centre for Advanced Bioenergy Research, Research and Development Centre; Agrawal, Ruchi [Indian Oil Corporation Ltd, Faridabad (India), Dept. of Bioenergy, DBT-IOC Centre for Advanced Bioenergy Research, Research and Development Centre; Bhagia, Samarthya [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemical and Biomolecular Engineering; Das, Parthapratim [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemical and Biomolecular Engineering; Ragauskas, Arthur J. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemical and Biomolecular Engineering

2017-10-17

The surplus availability of rice straw, its limited usage and environment pollution caused by inefficient burning has fostered research for its valorization to biofuels. This review elucidates the current status of rice straw potential around the globe along with recent advances in revealing the critical factors responsible for its recalcitrance and chemical properties. The role and accumulation of high silica content in rice straw has been elucidated with its impact on enzymatic hydrolysis in a biorefinery environment. The correlation of different pretreatment approaches in modifying the physiochemical properties of rice straw and improving the enzymatic accessibility has also been discussed. This study highlights new challenges, resolutions and opportunities for rice straw based biorefineries.

Fungal diversity of rice straw for meju fermentation.

Science.gov (United States)

Kim, Dae-Ho; Kim, Seon-Hwa; Kwon, Soon-Wo; Lee, Jong-Kyu; Hong, Seung-Beom

2013-12-01

Rice straw is closely associated with meju fermentation and it is generally known that the rice straw provides meju with many kinds of microorganisms. In order to elucidate the origin of meju fungi, the fungal diversity of rice straw was examined. Rice straw was collected from 12 Jang factories where meju are produced, and were incubated under nine different conditions by altering the media (MEA, DRBC, and DG18), and temperature (15°C, 25°C, and 35°C). In total, 937 strains were isolated and identified as belonging to 39 genera and 103 species. Among these, Aspergillus, Cladosporium, Eurotium, Fusarium, and Penicillium were the dominant genera. Fusarium asiaticum (56.3%), Cladosporium cladosporioides (48.6%), Aspergillus tubingensis (37.5%), A. oryzae (31.9%), Eurotium repens (27.1%), and E. chevalieri (25.0%) were frequently isolated from the rice straw obtained from many factories. Twelve genera and 40 species of fungi that were isolated in the rice straw in this study were also isolated from meju. Specifically, A. oryzae, C. cladosporioides, E. chevalieri, E. repens, F. asiaticum, and Penicillium polonicum (11.8%), which are abundant species in meju, were also isolated frequently from rice straw. C. cladosporioides, F. asiaticum, and P. polonicum, which are abundant in the low temperature fermentation process of meju fermentation, were frequently isolated from rice straw incubated at 15°C and 25°C, whereas A. oryzae, E. repens, and E. chevalieri, which are abundant in the high temperature fermentation process of meju fermentation, were frequently isolated from rice straw incubated at 25°C and 35°C. This suggests that the mycobiota of rice straw has a large influence in the mycobiota of meju. The influence of fungi on the rice straw as feed and silage for livestock, and as plant pathogens for rice, are discussed as well.

Using rice straw to manufacture ceramic bricks

Directory of Open Access Journals (Sweden)

Gorbunov German Ivanovich

2014-12-01

Full Text Available In the article, the co-authors offer their advanced and efficient methodologies for the recycling of the rice straw, as well as the novel approaches to the ceramic brick quality improvement through the application of the rice straw as the combustible additive and through the formation of amorphous silica in the course of the rice straw combustion. The co-authors provide characteristics of the raw materials, production techniques used to manufacture ceramic bricks, and their basic properties in the article. The co-authors describe the simulated process of formation of amorphous silica. The process in question has two independent steps (or options: 1 rice straw combustion and ash formation outside the oven (in the oxidizing medium, and further application of ash as the additive in the process of burning clay mixtures; 2 adding pre-treated rice straw as the combustible additive into the clay mixture, and its further burning in compliance with the pre-set temperature mode. The findings have proven that the most rational pre-requisite of the rice straw application in the manufacturing of ceramic bricks consists in feeding milled straw into the clay mixture to be followed by molding, drying and burning. Brick samples are highly porous, and they also demonstrate sufficient compressive strength. The co-authors have also identified optimal values of rice straw and ash content in the mixtures under research.

Microbial Activity and Silica Degradation in Rice Straw

Science.gov (United States)

Kim, Esther Jin-kyung

Abundantly available agricultural residues like rice straw have the potential to be feedstocks for bioethanol production. Developing optimized conditions for rice straw deconstruction is a key step toward utilizing the biomass to its full potential. One challenge associated with conversion of rice straw to bioenergy is its high silica content as high silica erodes machinery. Another obstacle is the availability of enzymes that hydrolyze polymers in rice straw under industrially relevant conditions. Microbial communities that colonize compost may be a source of enzymes for bioconversion of lignocellulose to products because composting systems operate under thermophilic and high solids conditions that have been shown to be commercially relevant. Compost microbial communities enriched on rice straw could provide insight into a more targeted source of enzymes for the breakdown of rice straw polysaccharides and silica. Because rice straw is low in nitrogen it is important to understand the impact of nitrogen concentrations on the production of enzyme activity by the microbial community. This study aims to address this issue by developing a method to measure microbial silica-degrading activity and measure the effect of nitrogen amendment to rice straw on microbial activity and extracted enzyme activity during a high-solids, thermophilic incubation. An assay was developed to measure silica-degrading enzyme or silicase activity. This process included identifying methods of enzyme extraction from rice straw, identifying a model substrate for the assay, and optimizing measurement techniques. Rice straw incubations were conducted with five different levels of nitrogen added to the biomass. Microbial activity was measured by respiration and enzyme activity. A microbial community analysis was performed to understand the shift in community structure with different treatments. With increased levels of nitrogen, respiration and cellulose and hemicellulose degrading activity

Succession of methanogenic archaea in rice straw incorporated into a Japanese rice field: estimation by PCR-DGGE and sequence analyses

Directory of Open Access Journals (Sweden)

Atsuo Sugano

2005-01-01

Full Text Available The succession and phylogenetic profiles of methanogenic archaeal communities associated with rice straw decomposition in rice-field soil were studied by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE analysis followed by 16S rDNA sequencing. Nylon bags containing either leaf sheaths or blades were buried in the plowed layer of a Japanese rice field under drained conditions during the off-crop season and under flooded conditions after transplanting. In addition, rice straw samples that had been buried in the rice field under drained conditions during the off-crop season were temporarily removed during spring plowing and then re-buried in the same rice field under flooded conditions at transplanting. Populations of methanogenic archaea were examined by amplification of the 16S rRNA genes in the DNA extracted from the rice straw samples. No PCR product was produced for samples of leaf sheath or blade prior to burial or after burial under drained conditions, indicating that the methanogen population was very small during decomposition of rice straw under oxic conditions. Many common bands were observed in rice straw samples of leaf sheath and blade during decomposition of rice straw under flooded conditions. Cluster analysis based on DGGE patterns divided methanogenic archaeal communities into two groups before and after the mid-season drainage. Sequence analysis of DGGE bands that were commonly present were closely related to Methanomicrobiales and Rice cluster I. Methanomicrobiales, Rice cluster I and Methanosarcinales were major members before the mid-season drainage, whereas the DGGE bands that characterized methanogenic archaeal communities after the mid-season drainage were closely related to Methanomicrobiales. These results indicate that mid-season drainage affected the methanogenic archaeal communities irrespective of their location on rice straw (sheath and blade and the previous history of decomposition

Effects of rice straw, biochar and mineral fertiliser on methane (CH4) and nitrous oxide (N2O) emissions from rice (Oryza sativa L.) grown in a rain-fed lowland rice soil of Cambodia

DEFF Research Database (Denmark)

Ly, Proyuth; Duong, Quynh Vu; Jensen, Lars Stoumann

2015-01-01

-control, rice straw (RS) and biochar (BC). Compound fertiliser was applied to all treatments. Rice was grown in columns packed with a paddy soil from Cambodia. Results revealed faster mineralisation of organic carbon (RS and BC) when applied in water-saturated conditions lasting for 2 weeks instead of flooding...

Effect of bamboo and rice straw biochars on the mobility and redistribution of heavy metals (Cd, Cu, Pb and Zn) in contaminated soil.

Science.gov (United States)

Lu, Kouping; Yang, Xing; Gielen, Gerty; Bolan, Nanthi; Ok, Yong Sik; Niazi, Nabeel Khan; Xu, Song; Yuan, Guodong; Chen, Xin; Zhang, Xiaokai; Liu, Dan; Song, Zhaoliang; Liu, Xingyuan; Wang, Hailong

2017-01-15

Biochar has emerged as an efficient tool to affect bioavailability of heavy metals in contaminated soils. Although partially understood, a carefully designed incubation experiment was performed to examine the effect of biochar on mobility and redistribution of Cd, Cu, Pb and Zn in a sandy loam soil collected from the surroundings of a copper smelter. Bamboo and rice straw biochars with different mesh sizes (Heavy metal concentrations in pore water were determined after extraction with 0.01 M CaCl 2 . Phytoavailable metals were extracted using DTPA/TEA (pH 7.3). The European Union Bureau of Reference (EUBCR) sequential extraction procedure was adopted to determine metal partitioning and redistribution of heavy metals. Results showed that CaCl 2 -and DTPA-extractable Cd, Cu, Pb and Zn concentrations were significantly (p soils, especially at 5% application rate, than those in the unamended soil. Soil pH values were significantly correlated with CaCl 2 -extractable metal concentrations (p metal fractions, and the effect was more pronounced with increasing biochar application rate. The effect of biochar particle size on extractable metal concentrations was not consistent. The 5% rice straw biochar treatment reduced the DTPA-extractable metal concentrations in the order of Cd metals were mainly bound in the soil organic matter fraction. The results demonstrated that the rice straw biochar can effectively immobilize heavy metals, thereby reducing their mobility and bioavailability in contaminated soils. Copyright © 2016 Elsevier Ltd. All rights reserved.

Oyster mushroom cultivation with rice and wheat straw.

Science.gov (United States)

Zhang, Ruihong; Li, Xiujin; Fadel, J G

2002-05-01

Cultivation of the oyster mushroom, Pleurotus sajor-caju, on rice and wheat straw without nutrient supplementation was investigated. The effects of straw size reduction method and particle size, spawn inoculation level, and type of substrate (rice straw versus wheat straw) on mushroom yield, biological efficiency, bioconversion efficiency, and substrate degradation were determined. Two size reduction methods, grinding and chopping, were compared. The ground straw yielded higher mushroom growth rate and yield than the chopped straw. The growth cycles of mushrooms with the ground substrate were five days shorter than with the chopped straw for a similar particle size. However, it was found that when the straw was ground into particles that were too small, the mushroom yield decreased. With the three spawn levels tested (12%, 16% and 18%), the 12% level resulted in significantly lower mushroom yield than the other two levels. Comparing rice straw with wheat straw, rice straw yielded about 10% more mushrooms than wheat straw under the same cultivation conditions. The dry matter loss of the substrate after mushroom growth varied from 30.1% to 44.3%. The straw fiber remaining after fungal utilization was not as degradable as the original straw fiber, indicating that the fungal fermentation did not improve the feed value of the straw.

Mercury in rice (Oryza sativa L.) and rice-paddy soils under long-term fertilizer and organic amendment.

Science.gov (United States)

Tang, Zhenya; Fan, Fangling; Wang, Xinyue; Shi, Xiaojun; Deng, Shiping; Wang, Dingyong

2018-04-15

High levels of mercury (Hg), especially methylmercury (MeHg), in rice is of concern due to its potential of entering food chain and the high toxicity to human. The level and form of Hg in rice could be influenced by fertilizers and other soil amendments. Studies were conducted to evaluate the effect of 24 years application of chemical fertilizers and organic amendments on total Hg (THg) and MeHg and their translocation in soil, plants, and rice grain. All treatments led to significantly higher concentrations of MeHg in grain than those from the untreated control. Of nine treatments tested, chemical fertilizers combining with returning rice straw (NPK1+S) led to highest MeHg concentration in grain and soil; while the nitrogen and potassium (NK) treatment led to significantly higher THg in grain. Concentrations of soil MeHg were significantly correlated with THg in soil (r = 0.59 *** ) and MeHg in grain (r = 0.48 *** ). Calcium superphosphate negatively affected plant bioavailability of soil Hg. MeHg concentration in rice was heavily influenced by soil Hg levels. Phosphorus fertilizer was a main source contributing to soil THg, while returning rice straw to the field contributed significantly to MeHg in soil and rice grain. As a result, caution should be exercised in soil treatment or when utilizing Hg-contaminated soils to produce rice for human consumption. Strategic management of rice straw and phosphorus fertilizer could be effective strategies of lowering soil Hg, which would ultimately lower MeHg in rice and the risk of Hg entering food chain. Copyright © 2017 Elsevier Inc. All rights reserved.

Pyrolysis of agricultural biomass residues: Comparative study of corn cob, wheat straw, rice straw and rice husk.

Science.gov (United States)

Biswas, Bijoy; Pandey, Nidhi; Bisht, Yashasvi; Singh, Rawel; Kumar, Jitendra; Bhaskar, Thallada

2017-08-01

Pyrolysis studies on conventional biomass were carried out in fixed bed reactor at different temperatures 300, 350, 400 and 450°C. Agricultural residues such as corn cob, wheat straw, rice straw and rice husk showed that the optimum temperatures for these residues are 450, 400, 400 and 450°C respectively. The maximum bio-oil yield in case of corn cob, wheat straw, rice straw and rice husk are 47.3, 36.7, 28.4 and 38.1wt% respectively. The effects of pyrolysis temperature and biomass type on the yield and composition of pyrolysis products were investigated. All bio-oils contents were mainly composed of oxygenated hydrocarbons. The higher area percentages of phenolic compounds were observed in the corn cob bio-oil than other bio-oils. From FT-IR and 1 H NMR spectra showed a high percentage of aliphatic functional groups for all bio-oils and distribution of products is different due to differences in the composition of agricultural biomass. Copyright © 2017 Elsevier Ltd. All rights reserved.

Radiation disinfection of rice-straw products

International Nuclear Information System (INIS)

Ito, Hitoshi; Ishigaki, Isao; Ohki, Yumi.

1991-01-01

For the quarantine treatment of rice-straw products from foreign countries, irradiation effects of gamma-rays and electron beams on plant pathogenic microorganisms especially on fungi were investigated. The total aerobic bacteria in rice-straw was determined to be 3x10 7 - 3x10 8 per gram which consisted mainly of Pseudomonas, Flavobacterium, Arthrobacter and Erwinia. The principal bacteria in rice-straw could be eliminated with 5 kGy of gamma irradiation. Deinococcus proteolyticus and Pseudomonas radiora were the main survivors at 5 to 12 kGy of irradiation. Saprophytic fungus which belongs to Dimorphospora also survived up to 8 kGy of irradiation. The D 10 values of 26 strains of fungi isolated from rice-straw were 1.1 to 2.5 times higher in the dry condition compared to the values when irradiated in 0.067 M phosphate buffer solution. The induction dose in the dry condition also increased from 1.5 to 10 times than that in the wet condition. In the case of electron beam irradiation of fungi under dry conditions, D 10 values were about 1.3 times higher than that of gamma irradiation. From this study, the dose necessary to reduce the plant pathogenic fungi in rice-straw at a level below 10 -4 per gram was estimated to be as 7-8 kGy for gamma-irradiation and 10 kGy for electron beam irradiation. (author)

Radiation disinfection of rice-straw products

Energy Technology Data Exchange (ETDEWEB)

Ito, Hitoshi; Ishigaki, Isao (Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment); Ohki, Yumi

1991-11-01

For the quarantine treatment of rice-straw products from foreign countries, irradiation effects of gamma-rays and electron beams on plant pathogenic microorganisms especially on fungi were investigated. The total aerobic bacteria in rice-straw was determined to be 3x10{sup 7} - 3x10{sup 8} per gram which consisted mainly of Pseudomonas, Flavobacterium, Arthrobacter and Erwinia. The principal bacteria in rice-straw could be eliminated with 5 kGy of gamma irradiation. Deinococcus proteolyticus and Pseudomonas radiora were the main survivors at 5 to 12 kGy of irradiation. Saprophytic fungus which belongs to Dimorphospora also survived up to 8 kGy of irradiation. The D{sub 10} values of 26 strains of fungi isolated from rice-straw were 1.1 to 2.5 times higher in the dry condition compared to the values when irradiated in 0.067 M phosphate buffer solution. The induction dose in the dry condition also increased from 1.5 to 10 times than that in the wet condition. In the case of electron beam irradiation of fungi under dry conditions, D{sub 10} values were about 1.3 times higher than that of gamma irradiation. From this study, the dose necessary to reduce the plant pathogenic fungi in rice-straw at a level below 10{sup -4} per gram was estimated to be as 7-8 kGy for gamma-irradiation and 10 kGy for electron beam irradiation. (author).

Removal of phenol from aqueous solution using rice straw as adsorbent

Science.gov (United States)

Sarker, Nandita; Fakhruddin, A. N. M.

2017-06-01

Phenol is an environmental pollutant; the present study was conducted to examine the adsorption of phenol by rice straw. For this purpose raw (untreated), physically treated (boiled and dried) and thermally treated (heated at 230 °C for 3 h to produce ash) rice straw were selected to determine phenol removal efficiency at different contact times and adsorbent dosages for 1 and Percentage of removal of phenol increased as the adsorbent dose increase. The removal efficiency increase in the order of: raw rice straw ash) rice straw. Langmuir and Freundlich isotherm was developed for 1 and ash) treated rice straw. Freundlich isotherm best fit the equilibrium data for 1 mm thermally treated rice straw. The results showed that thermally treated rice straw (ash) can be developed as a potential adsorbent for phenol removal from aqueous solution.

Contribution of rice straw carbon to CH4 emission from rice paddies using 13C-enriched rice straw

Science.gov (United States)

Watanabe, Akira; Yoshida, Mariko; Kimura, Makoto

1998-04-01

It is generally recognized that the application of rice straw (RS) increases CH4 emission from rice paddies. To estimate the contribution of RS carbon to CH4 emission, a pot experiment was conducted using 13C-enriched RS. The percentage contributions of RS carbon to CH4 emission throughout the rice growth period were 10±1, 32±3, and 43±3% for the treatments with RS applied at the rates of 2, 4, and 6 g kg-1 soil, respectively. The increase in the rate of application of RS increased CH4 emission derived from both RS carbon and other carbon sources. The percentage contribution of RS carbon to CH4 emission was larger in the earlier period (maximum 96%) when the decomposition rate of RS was larger. After RS decomposition had slowed, CH4 emission derived from RS carbon decreased. However, the δ13C values of CH4 emitted from the pots with 13C-enriched RS applied at rates of 4 and 6 g kg-1 soil were significantly higher than those from the pots with natural RS until the harvesting stage. An increased atom-13C% of roots of rice plants growing in the pots with 6 g kg-1 of 13C-enriched RS at around the maximum tiller number stage and a decrease during the following 2 months suggested that rice plants assimilated RS carbon once and then released a portion of it. This supply of RS carbon from roots may be one of the sources of CH4 in the late period of rice growth.

Evaluation of soil characteristics potentially affecting arsenic concentration in paddy rice (Oryza sativa L.)

International Nuclear Information System (INIS)

Bogdan, Katja; Schenk, Manfred K.

2009-01-01

Paddy rice may contribute considerably to the human intake of As. The knowledge of soil characteristics affecting the As content of the rice plant enables the development of agricultural measures for controlling As uptake. During field surveys in 2004 and 2006, plant samples from 68 fields (Italy, Po-area) revealed markedly differing As concentration in polished rice. The soil factors total As (aquaregia) , pH, grain size fractions, total C, plant available P (CAL) , poorly crystalline Fe (oxal.) and plant available Si (Na-acetate) content that potentially affect As content of rice were determined. A multiple linear regression analysis showed a significant positive influence of the total As (aquaregia) and plant available P (CAL) content and a negative influence of the poorly crystalline Fe (oxal.) content of the soil on the As content in polished rice and rice straw. Si concentration in rice straw varied widely and was negatively related to As content in straw and polished rice. - Field selection for total As, poorly crystalline Fe and plant available P in soil might contribute to control As content of paddy rice.

Differences in Cellulosic Supramolecular Structure of Compositionally Similar Rice Straw Affect Biomass Metabolism by Paddy Soil Microbiota.

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Tatsuki Ogura

Full Text Available Because they are strong and stable, lignocellulosic supramolecular structures in plant cell walls are resistant to decomposition. However, they can be degraded and recycled by soil microbiota. Little is known about the biomass degradation profiles of complex microbiota based on differences in cellulosic supramolecular structures without compositional variations. Here, we characterized and evaluated the cellulosic supramolecular structures and composition of rice straw biomass processed under different milling conditions. We used a range of techniques including solid- and solution-state nuclear magnetic resonance (NMR and Fourier transform infrared spectroscopy followed by thermodynamic and microbial degradability characterization using thermogravimetric analysis, solution-state NMR, and denaturing gradient gel electrophoresis. These measured data were further analyzed using an "ECOMICS" web-based toolkit. From the results, we found that physical pretreatment of rice straw alters the lignocellulosic supramolecular structure by cleaving significant molecular lignocellulose bonds. The transformation from crystalline to amorphous cellulose shifted the thermal degradation profiles to lower temperatures. In addition, pretreated rice straw samples developed different microbiota profiles with different metabolic dynamics during the biomass degradation process. This is the first report to comprehensively characterize the structure, composition, and thermal degradation and microbiota profiles using the ECOMICS toolkit. By revealing differences between lignocellulosic supramolecular structures of biomass processed under different milling conditions, our analysis revealed how the characteristic compositions of microbiota profiles develop in addition to their metabolic profiles and dynamics during biomass degradation.

The Short-Term Effects of Rice Straw Biochar, Nitrogen and Phosphorus Fertilizer on Rice Yield and Soil Properties in a Cold Waterlogged Paddy Field

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Linlin Si

2018-02-01

Full Text Available Crop productivity in cold waterlogged paddy fields can be constrained by chronic flooding stress and low temperature. Farmers typically use chemical fertilizer to improve crop production, but this conventional fertilization is not very effective in a cold waterlogged paddy field. Biochar amendment has been proposed as a promising management approach to eliminating these obstacles. However, little is known about the performance of biochar when combined with N fertilizer and P fertilizer in cold waterlogged soils. The aim of this study was, therefore, to assess the main effects and interactive effects of rice straw biochar, N and P fertilizer on rice growth and soil properties in a cold waterlogged paddy field. The field treatments consisted of a factorial combination of two biochar levels (0 and 2.25 t ha−1, two N fertilizer levels (120.0 and 180.0 kg ha−1 and two P fertilizer levels (37.5 and 67.5 kg ha−1 which were arranged in a randomized block design, with three replicates. Results confirmed that biochar application caused a significant increase in the soil pH due to its liming effect, while this application resulted in a significant decrease in soil exchangeable cations, such as exchangeable Ca, Mg, Al and base cations. The interactive effect of N fertilizer, P fertilizer and biochar was significant for soil total N. Moreover, a negative effect of biochar on the internal K use efficiency suggested that K uptake into rice may benefit from biochar application. According to the partial Eta squared values, the combined application of N fertilizer and biochar was as effective as pure P fertilization at increasing straw P uptake. The addition of biochar to farmers’ fertilization practice treatment (180.0 kg N ha−1, 67.5 kg P2O5 ha−1 and 67.5 kg K2O ha−1 significantly increased rice yield, mainly owing to improvements in grains per panicle. However, notable effects of biochar on rice yield and biomass production were not detected

Life cycle assessment of rice straw-based power generation in Malaysia

International Nuclear Information System (INIS)

Shafie, S.M.; Masjuki, H.H.; Mahlia, T.M.I.

2014-01-01

This paper presents an application of LCA (Life Cycle Assessment) with a view to analyzing the environment aspects of rice straw-based power generation in Malaysia. It also compares rice straw-based power generation with that of coal and natural gas. GHG (Greenhouse gas) emission savings were calculated. It finds that rice straw power generation can save GHG (greenhouse gas) emissions of about 1.79 kg CO 2 -eq/kWh compared to coal-based and 1.05 kg CO 2 -eq/kWh with natural gas based power generation. While the development of rice straw-based power generation in Malaysia is still in its early stage, these paddy residues offer a large potential to generate electricity because of their availability. Rice straw power plants not only could solve the problem of removing rice straw from fields without open burning, but also could reduce GHG emissions that contribute to climate change, acidification, and eutrophication, among other environmental problems. - Highlights: • Overall rice straw preparations contribute 224.48 g CO 2 -eq/kg rice straw. • The most constraints due to GHG (greenhouse gas) emission is from transportation. • Distance collection centre to plant less than 110 km to obtains minimum emissions. • Rice straw can save GHG emissions 1.79 kg CO 2 -eq/kWh compared to coal power. • GHG saving 1.05 kg CO 2 -eq/kWh compared to natural gas based power generation

[Influence of Different Straws Returning with Landfill on Soil Microbial Community Structure Under Dry and Water Farming].

Science.gov (United States)

Lan, Mu-ling; Gao, Ming

2015-11-01

Based on rice, wheat, corn straw and rape, broad bean green stalk as the research object, using phospholipid fatty acid (PLFA) method, combining principal component analysis method to study the soil microbial quantity, distribution of flora, community structure characteristics under dry and water farming as two different cultivated land use types. The PLFA analysis results showed that: under dry farming, total PLFA quantity ranged 8.35-25.15 nmol x g(-1), showed rape > broad bean > corn > rice > wheat, rape and broad bean significantly increased total PLFA quantity by 1.18 and 1.08 times compared to the treatment without straw; PLFA quantity of bacterial flora in treatments with straws was higher than that without straw, and fungal biomass was significantly increased, so was the species richness of microbial community. Under water faming, the treatments of different straws returning with landfill have improved the PLFA quantity of total soil microbial and flora comparing with the treatment without straw, fungi significantly increased, and species richness of microbial communities value also increased significantly. Total PLFA quantity ranged 4.04-22.19 nmol x g(-1), showed rice > corn > wheat > broad bean > rape, which in rape and broad bean treatments were lower than the treatment without straw; fungal PLFA amount in 5 kinds of straw except broad bean treatment was significantly higher than that of the treatment without straw, bacteria and total PLFA quantity in broad bean processing were significantly lower than those of other treatments, actinomycetes, G+, G- had no significant difference between all treatments; rice, wheat, corn, rape could significantly increase the soil microbial species richness index and dominance index under water faming. The results of principal component analysis showed that broad bean green stalk had the greatest impact on the microbial community structure in the dry soil, rape green stalk and wheat straw had the biggest influence on

Potassium hydroxide pulping of rice straw in biorefinery initiatives.

Science.gov (United States)

Jahan, M Sarwar; Haris, Fahmida; Rahman, M Mostafizur; Samaddar, Purabi Rani; Sutradhar, Shrikanta

2016-11-01

Rice straw is supposed to be one of the most important lignocellulosic raw materials for pulp mill in Asian countries. The major problem in rice straw pulping is silica. The present research is focused on the separation of silica from the black liquor of rice straw pulping by potassium hydroxide (KOH) and pulp evaluation. Optimum KOH pulping conditions of rice straw were alkali charge 12% as NaOH, cooking temperature 150°C for 2h and material to liquor ratio, 1:6. At this condition pulp yield was 42.4% with kappa number 10.3. KOH pulp bleached to 85% brightness by D0EpD1 bleaching sequences with ClO2 consumption of 25kg/ton of pulp. Silica and lignin were separated from the black liquor of KOH pulping. The amount of recovered silica, lignin and hemicelluloses were 10.4%, 8.4% and 13.0%. The papermaking properties of KOH pulp from rice straw were slightly better than those of corresponding NaOH pulp. Copyright © 2016 Elsevier Ltd. All rights reserved.

Potential alternatives of heat and power technology application using rice straw in Thailand

International Nuclear Information System (INIS)

Suramaythangkoor, Tritib; Gheewala, Shabbir H.

2010-01-01

Rice straw could be used for heat and power with the current technologies available in Thailand. The cost of rice straw for power generation at 0.38-0.61 Baht/MJ e (at rice straw price 930-1500 Baht/t) is not competitive with coal at 0.30 Baht/MJ e but comparable with other biomass at 0.35-0.53 Baht/MJ e . However, utilization of rice straw in industrial boilers is a more competitive and flexible option with two alternatives; (1) installing rice straw fired boilers instead of heavy oil fired or natural gas ones when selecting new boilers; and (2) fuel switching from coal to rice straw for existing boilers with cost saving of feedstock supply by 0.01 Baht/MJ h . Based on its properties (Slagging index, R s = 0.04; fouling index, R f 0.24), rice straw is not expected to have significant operating problems or different emissions compared with wheat straw and rice husk under similar operating conditions. (author)

The absorption and distribution of Cesium-134 in rice-soil system

International Nuclear Information System (INIS)

Xu Yinliang; Chen Chuanqun; Chen Bin; Sun Zhiming

1991-01-01

Dynamics of absorption of 134 Cs by rice shows that absorption rate is the fastest at boot stage; absorption capacities of 134 Cs in soils are different with the different physical-chemical properties of soils; absorption amounts vary with the time of irrigating 134 Cs; the closer the irrigation time to mature stage is, the more the absorption amount of 134 Cs in rice will be; the more the irrigating times are, and the higher the radioactivity of 134 Cs in irrigating water is, the more the absorption amount in rice will be. After brown rice is polished, contamination of 134 Cs can be decreased by 22.6-45.6%. The order of specific activity in rice is: bran > root > straw > husk > polished rice. Percentage activity of straw, brown rice, root and husk is 51.4%, 28.4%, 11.8% and 8.4% respectively. The migration of 134 Cs is very slow in soil and 95.1% of 134 Cs is concentrated in surface soil (0-2.5 cm). The distribution ratio of 134 Cs in the rice and soil is 6.1%:93.9%. Potassium ion can inhibit the absorption of 134 Cs by rice. There is an exponential function between the concentration of potassium ion and specific activity of 134 Cs in rice

Effect of Interplanting with Zero Tillage and Straw Manure on Rice Growth and Rice Quality

Directory of Open Access Journals (Sweden)

Shi-ping LIU

2007-09-01

Full Text Available The interplanting with zero-tillage of rice, i.e. direct sowing rice 10–20 days before wheat harvesting, and remaining about 30-cm high stubble after cutting wheat or rice with no tillage, is a new cultivation technology in wheat-rice rotation system. To study the effects of interplanting with zero tillage and straw manure on rice growth and quality, an experiment was conducted in a wheat-rotation rotation system. Four treatments, i.e. ZIS (Zero-tillage, straw manure and rice interplanting, ZI (Zero-tillage, no straw manure and rice interplanting, PTS (Plowing tillage, straw manure and rice transplanting, and PT (Plowing tillage, no straw manure and rice transplanting, were used. ZIS reduced plant height, leaf area per plant and the biomass of rice plants, but the biomass accumulation of rice at the late stage was quicker than that under conventional transplanting cultivation. In the first year (2002, there was no significant difference in rice yield among the four treatments. However, rice yield decreased in interplanting with zero-tillage in the second year (2003. Compared with the transplanting treatments, the number of filled grains per panicle decreased but 1000-grain weight increased in interplanting with zero-tillage, which were the main factors resulting in higher yield. Interplanting with zero-tillage improved the milling and appearance qualities of rice. The rates of milled and head rice increased while chalky rice rate and chalkiness decreased in interplanting with zero-tillage. Zero-tillage and interplanting also affected rice nutritional and cooking qualities. In 2002, ZIS showed raised protein content, decreased amylose content, softer gel consistency, resulting in improved rice quality. In 2003, zero-tillage and interplanting decreased protein content and showed similar amylose content as compared with transplanting treatments. Moreover, protein content in PTS was obviously increased in comparison with the other three treatments

Impacts of soil incorporation of pre-incubated silica-rich rice residue on soil biogeochemistry and greenhouse gas fluxes under flooding and drying.

Science.gov (United States)

Gutekunst, Madison Y; Vargas, Rodrigo; Seyfferth, Angelia L

2017-09-01

Incorporation of silica-rich rice husk residue into flooded paddy soil decreases arsenic uptake by rice. However, the impact of this practice on soil greenhouse gas (GHG) emissions and elemental cycling is unresolved particularly as amended soils experience recurrent flooding and drying cycles. We evaluated the impact of pre-incubated silica-rich rice residue incorporation to soils on pore water chemistry and soil GHG fluxes (i.e., CO 2 , CH 4 , N 2 O) over a flooding and drying cycle typical of flooded rice cultivation. Soils pre-incubated with rice husk had 4-fold higher pore water Si than control and 2-fold higher than soils pre-incubated with rice straw, whereas the pore water As and Fe concentrations in soils amended with pre-incubated straw and husk were unexpectedly similar (maximum ~0.85μM and ~450μM levels, respectively). Pre-incubation of residues did not affect Si but did affect the pore water levels of As and Fe compared to previous studies using fresh residues where straw amended soils had higher As and Fe in pore water. The global warming potential (GWP) of soil GHG emissions decreased in the order straw (612±76g CO 2 -eqm -2 )>husk (367±42gCO 2 -eqm -2 )>ashed husk=ashed straw (251±26 and 278±28gCO 2 -eqm -2 )>control (186±23gCO 2 -eqm -2 ). The GWP increase due to pre-incubated straw amendment was due to: a) larger N 2 O fluxes during re-flooding; b) smaller contributions from larger CH 4 fluxes during flooded periods; and c) higher CH 4 and CO 2 fluxes at the onset of drainage. In contrast, the GWP of the husk amendment was dominated by CO 2 and CH 4 emissions during flooded and drainage periods, while ashed amendments increased CO 2 emissions particularly during drainage. This experiment shows that ashed residues and husk addition minimizes GWP of flooded soils and enhances pore water Si compared to straw addition even after pre-incubation. Copyright © 2017 Elsevier B.V. All rights reserved.

Life cycle GHG analysis of rice straw bio-DME production and application in Thailand

International Nuclear Information System (INIS)

Silalertruksa, Thapat; Gheewala, Shabbir H.; Sagisaka, Masayuki; Yamaguchi, Katsunobu

2013-01-01

Highlights: • Life cycle GHG emissions of rice straw bio-DME production in Thailand are assessed. • Bio-DME replaces diesel in engines and supplements LPG for household application. • Rice straw bio-DME in both cases of substitution helps reduce GHG emissions. - Abstract: Thailand is one of the leading countries in rice production and export; an abundance of rice straw, therefore, is left in the field nowadays and is commonly burnt to facilitate quick planting of the next crop. The study assesses the life cycle greenhouse gas (GHG) emissions of using rice straw for bio-DME production in Thailand. The analysis is divided into two scenarios of rice straw bio-DME utilization i.e. used as automotive fuel for diesel engines and used as LPG supplement for household application. The results reveal that that utilization of rice straw for bio-DME in the two scenarios could help reduce GHG emissions by around 14–70% and 2–66%, respectively as compared to the diesel fuel and LPG substituted. In case rice straw is considered as a by-product of rice cultivation, the cultivation of rice straw will be the major source of GHG emission contributing around 50% of the total GHG emissions of rice straw bio-DME production. Several factors that can affect the GHG performance of rice straw bio-DME production are discussed along with measures to enhance GHG performance of rice straw bio-DME production and utilization

Changes in heavy metal bioavailability and speciation from a Pb-Zn mining soil amended with biochars from co-pyrolysis of rice straw and swine manure.

Science.gov (United States)

Meng, Jun; Tao, Mengming; Wang, Lili; Liu, Xingmei; Xu, Jianming

2018-08-15

Biochar has been utilized as a good amendment to immobilize heavy metals in contaminated soils. However, the effectiveness of biochar in metal immobilization depends on biochar properties and metal species. In this study, the biochars produced from co-pyrolysis of rice straw with swine manure at 400°C were investigated to evaluate their effects on bioavailability and chemical speciation of four heavy metals (Cd, Cu, Pb and Zn) in a Pb-Zn contaminated soil through incubation experiment. Results showed that co-pyrolysis process significantly change the yield, ash content, pH, and electrical conductivity (EC) of the blended biochars compared with the single straw/manure biochar. The addition of these biochars significantly increased the soil pH, EC, and dissolved organic carbon (DOC) concentrations. The addition of biochars at a rate of 3% significantly reduced the CaCl 2 -extractable metal concentrations in the order of Pb>Cu>Zn>Cd. The exchangeable heavy metals decreased in all the biochar-amended soils whereas the carbonate-bound metal speciation increased. The increase in soil pH and the decrease in the CaCl 2 extractable metals indicated that these amendments can directly transform the highly availability metal speciation to the stable speciation in soils. In conclusion, biochar derived from co-pyrolysis of rice straw with swine manure at a mass ratio of 3:1 could most effectively immobilize the heavy metals in the soil. Copyright © 2018 Elsevier B.V. All rights reserved.

Composition of the enzymatic and acid hydrolyzates of gamma-irradiated rice straw

International Nuclear Information System (INIS)

Abad, L.V.; Banzon, R.B.; Rosa, A. de la

1989-01-01

Gamma irradiation was utilized to induce structural changes in rice straw that would enhance the conversion of its cellulose and ligno-cellulosic components to glucose and other reducing sugars. With the appropriate fermentation conditions these sugars can eventually be converted into alcohol. Rice straw materials were irradiated at varying doses (0-500 kgy) and hydrolyzed by the use of a) cellulose enzyme and b) 1% sulfuric acid. The composition of the hydrolyzates of rice straw was studied by thin layer chromatography (TLC) coupled with the Nelson-Somogyi test for its quantification. Acid hydrolyzates of rice straw showed a maximum increase of 16.46% in its total reducing sugars at 300 Kgy. TLC of the acid hydrolyzates of rice straw revealed the presence of glucose, xylose, arabinose, and cellobiose. However, it was only with xylose that a significant increase in yield was observed with the non-irradiated straw 12.55% xylose yield was noted while with rice straw-irradiated at 400 Kgy a maximum yield of 15.90% xylose was obtained. Total reducing sugar of the enzymatic hydrolyzate of rice straw showed a maximum increase of 205% at 500 Kgy. TLC revealed that only glucose was present in the enzymatic hydrolyzate. Glucose yield increase from 2.49% (0 Kgy) to 7.31% (500 Kgy). The results showed that radiation pre-treatment of rice straw induces significant increases in reducing sugar for both enzymatic and hydrolyzate. (Auth.). 2 tabs.; 1 fig

A Study Of Biogas Production From Rice Straw In An Underground Digester

International Nuclear Information System (INIS)

Akpabio, O; Sambo, A.S; Fai, F

2002-01-01

The rising cost of petroleum products, the growing world population with diminishing resources and increasing wastes has brought about the need for sourcing alternative resources in order to bring about sustainable development. In this regard. this research was conceived to innovate design and construction of a biogas digester and to study the production of biogas from rice straw. An underground biogas digester was designed. Constructed and tested. The test digestion produced biogas yield of 0.020 M/KXg from green cow dung. In the study of biogas production from rice straw, four bench digesters of one d m3 (I litre) each were used. The bench digester produced biogas yields of 0.0149 m3/kg of rice straw, 0.0389 m3/kg of a mixture of rice straw and cow dung and 0.0792 m3/kg of cow dung. Scaled up digestion of rice straw in the underground digester gave biogas yield of 7.37 x 104 m3/kg. The biogas produced from rice straw was found to contain 38.52% of carbon dioxide and no hydrogen sulphide. It was concluded that the biogas generation from rice straw was encouraging, but scale up yields was low. The limiting factors on biogas production from rice straw with the effect of digester design or biogas production are presented and discussed

Effects of straw incorporation along with microbial inoculant on methane and nitrous oxide emissions from rice fields

Energy Technology Data Exchange (ETDEWEB)

Liu, Gang; Yu, Haiyang [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Ma, Jing [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008 (China); Xu, Hua, E-mail: hxu@issas.ac.cn [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71 East Beijing Road, Nanjing 210008 (China); Wu, Qinyan; Yang, Jinghui; Zhuang, Yiqing [Zhenjiang Institute of Agricultural Science of Hilly Regions in Jiangsu, Jurong 212400 (China)

2015-06-15

Incorporation of straw together with microbial inoculant (a microorganism agent, accelerating straw decomposition) is being increasingly adopted in rice cultivation, thus its effect on greenhouse gas (GHG) emissions merits serious attention. A 3-year field experiment was conducted from 2010 to 2012 to investigate combined effect of straw and microbial inoculant on methane (CH{sub 4}) and nitrous oxide (N{sub 2}O) emissions, global warming potential (GWP) and greenhouse gas intensity (GHGI) in a rice field in Jurong, Jiangsu Province, China. The experiment was designed to have treatment NPK (N, P and K fertilizers only), treatment NPKS (NPK plus wheat straw), treatment NPKSR (NPKS plus Ruilaite microbial inoculant) and treatment NPKSJ (NPKS plus Jinkuizi microbial inoculant). Results show that compared to NPK, NPKS increased seasonal CH{sub 4} emission by 280–1370%, while decreasing N{sub 2}O emission by 7–13%. When compared with NPKS, NPKSR and NPKSJ increased seasonal CH{sub 4} emission by 7–13% and 6–12%, respectively, whereas reduced N{sub 2}O emission by 10–27% and 9–24%, respectively. The higher CH{sub 4} emission could be attributed to the higher soil CH{sub 4} production potential triggered by the combined application of straw and microbial inoculant, and the lower N{sub 2}O emission to the decreased inorganic N content. As a whole, the benefit of lower N{sub 2}O emission was completely offset by increased CH{sub 4} emission, resulting in a higher GWP for NPKSR (5–12%) and NPKSJ (5–11%) relative to NPKS. Due to NPKSR and NPKSJ increased rice grain yield by 3–6% and 2–4% compared to NPKS, the GHGI values for NPKS, NPKSR and NPKSJ were comparable. These findings suggest that incorporating straw together with microbial inoculant would not influence the radiative forcing of rice production in the terms of per unit of rice grain yield relative to the incorporation of straw alone. - Highlights: • This paper presents 3-year measurements of CH

Generating a positive energy balance from using rice straw for anaerobic digestion

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V.H. Nguyen

2016-11-01

The net energy of the rice straw supply chain for biogas generation through AD is 3,500 MJ per ton of straw. This rice straw management option can provide a 70% net output energy benefit. The research highlighted the potential of rice straw as a clean fuel source with a positive energy balance, helping to reduce greenhouse gas emissions compared with the existing practice of burning it in the field.

Rice straw-wood particle composite for sound absorbing wooden construction materials.

Science.gov (United States)

Yang, Han-Seung; Kim, Dae-Jun; Kim, Hyun-Joong

2003-01-01

In this study, rice straw-wood particle composite boards were manufactured as insulation boards using the method used in the wood-based panel industry. The raw material, rice straw, was chosen because of its availability. The manufacturing parameters were: a specific gravity of 0.4, 0.6, and 0.8, and a rice straw content (10/90, 20/80, and 30/70 weight of rice straw/wood particle) of 10, 20, and 30 wt.%. A commercial urea-formaldehyde adhesive was used as the composite binder, to achieve 140-290 psi of bending modulus of rupture (MOR) with 0.4 specific gravity, 700-900 psi of bending MOR with 0.6 specific gravity, and 1400-2900 psi of bending MOR with a 0.8 specific gravity. All of the composite boards were superior to insulation board in strength. Width and length of the rice straw particle did not affect the bending MOR. The composite boards made from a random cutting of rice straw and wood particles were the best and recommended for manufacturing processes. Sound absorption coefficients of the 0.4 and 0.6 specific gravity boards were higher than the other wood-based materials. The recommended properties of the rice straw-wood particle composite boards are described, to absorb noises, preserve the temperature of indoor living spaces, and to be able to partially or completely substitute for wood particleboard and insulation board in wooden constructions.

Pelletizing of rice straws: A potential solid fuel from agricultural residues

International Nuclear Information System (INIS)

Puad, E.; Wan Asma, I; Shaharuddin, H.; Mahanim, S.; Rafidah, J.

2010-01-01

Full text: Rice straw is the dry stalks of rice plants, after the grain and chaff have been removed. More than 1 million tonnes of rice straw are produced in MADA in the northern region of Peninsular Malaysia annually. Burning in the open air is the common technique of disposal that contribute to air pollution. In this paper, a technique to convert these residues into solid fuel through pelletizing is presented. The pellets are manufactured from rice straw and sawdust in a disc pelletizer. The pellet properties are quite good with good resistance to mechanical disintegration. The pellets have densities between 1000 and 1200 kg/ m 3 . Overall, converting rice straw into pellets has increased its energy and reduced moisture content to a minimum of 8 % and 30 % respectively. The gross calorific value is about 15.6 MJ/ kg which is lower to sawdust pellet. The garnering of knowledge in the pelletization process provides a path to increase the use of this resource. Rice straw pellets can become an important renewable energy source in the future. (author)

Isolation and characterization of pulp from sugarcane bagasse and rice straw

International Nuclear Information System (INIS)

Saiful Azhari, S.; Suhardy, D.; Kasim, F.H; Nazry Saleh, M.

2007-01-01

The amount of sugarcane bagasse and rice straw in the state of Perlis (Malaysia) is abundant while its utilization is still limited. One of the alternatives for the bagasse and straw utilization is as pulp raw material. This paper reviews on pulp from sugarcane bagasse and rice straw and its suitability for paper production. In this study, the pulp was extracted by the Soxhlet extraction method. The objective of this study was to investigate the cellulose, lignin and silica content of the pulp from sugarcane bagasse and rice straw. For rice straw, the presence of large amount of pentosanes in the pulp and black liquors, which also contain silica were decreased the using of straw in the paper industry. Therefore, formic acid pulping and NaOH treatment are studied to reduce or prevent silica. The isolated pulp samples were further characterized by Scanning Electron Microscope (SEM) to investigate their fiber dimensions. (Author)

Phosphate dynamics on the application of rice straw compost-biochar and phosphate fertilization in rice fields

International Nuclear Information System (INIS)

Ania Citraresmini; Taufiq Bachtiar

2016-01-01

Soil productivity is determined by soil characteristics itself, which consist of physical, chemical and biological character. The linkage between these three properties can be represented by a single indicator, namely the carbon content in the soil. One of the effects of soil organic matter fulfillment is the availability of soil nutrients, especially to the nutrient that limits the lowland rice production. In this case, P (phosphorus) nutrient become a limiting factor because their numbers are often in abundance but in a form that can not be used by plants. Experiments were carried out with the aim of studying the impact of straw compost application that integrates with Biochar, to the availability of P in lowland soil. The interaction of straw compost + Biochar with PSB inoculation and P sources, become the treatment that being tested in the experiment. Randomized Block Design with factorial pattern is applied as design experiment. As the first factor is the application dose of straw compost + Biochar, consists of 5 levels of treatment : 0; 1; 2; 3; 4 t ha -1 . Second factor is several sources of P, consist of 5 levels of treatment : without P sources (p 0 ); 100 kg ha -1 SP-36 fertilizer (p1); rock phosphate at the dose of 163 kg ha -1 (p 2 ); PSB inoculation at the inoculation dose of 2 kg ha -1 (p 3 ); and rock phosphate inoculated with PSB (p 4 ). The experiment done in the green house of PAIR-BATAN experimental station, Jakarta, on March-July 2014. Phosphorus dynamic as a result of the tested treatments, determined by using radioisotope 32 P technology at the activity of 30 mCi and described clearly on the plant P uptake data of Sidenuk rice plant variety. The experiment result showed that the treatments applied is causing significantly different response on the soil C-organic, the number of PSB populations, 32 P plant counting and plant P uptake derived from several P sources in the plant. (author)

Influence of rice straw-based polyols on the morphology, thermal ...

African Journals Online (AJOL)

replacement of rice straw-based polyols produced closed cell structures suitable for insulation material as revealed in Scanning electron microscope images. Higher percentage of rice straw-based polyols replacement will trigger cell wall structure rapturing that will deteriorate the properties of polyurethane foam.

Effect of peanut shell and wheat straw biochar on the availability of Cd and Pb in a soil-rice (Oryza sativa L.) system.

Science.gov (United States)

Xu, Chao; Chen, Hao-Xiang; Xiang, Qian; Zhu, Han-Hua; Wang, Shuai; Zhu, Qi-Hong; Huang, Dao-You; Zhang, Yang-Zhu

2018-01-01

Soil amendments, such as biochar, have been used to enhance the immobilization of heavy metals in contaminated soil. A pot experiment was conducted to immobilize the available cadmium (Cd) and lead (Pb) in soil using peanut shell biochar (PBC) and wheat straw biochar (WBC), and to observe the accumulation of these heavy metals in rice (Oryza sativa L.). The application of PBC and WBC led to significantly higher pH, soil organic carbon (SOC), and cation exchange capacity (CEC) in paddy soil, while the content of MgCl 2 -extractable Cd and Pb was lower than that of untreated soil. MgCl 2 -extractable Cd and Pb showed significant negative correlations with pH, SOC, and CEC (p rice plants. Specially, when compared to the corresponding concentrations in rice grown in control soils, 5% PBC addition lowered Cd and Pb concentrations in grains by 22.9 and 12.2%, respectively, while WBC addition lowered them by 29.1 and 15.0%, respectively. Compared to Pb content, Cd content was reduced to a greater extent in grain by PBC and WBC. These results suggest that biochar application is effective for immobilizing Cd and Pb in contaminated paddy soil, and reduces their bioavailability in rice. Biochar could be used as a soil amendment for the remediation of soils contaminated with heavy metals.

Effect of 60Co γ-rays irradiation on rice straw fibre structure and enzyme hydrolyzation

International Nuclear Information System (INIS)

Chen Jingping; Li Wenge; Peng Ling; Wang Keqin; Xiong Xingyao

2008-01-01

The effect of improving enzyme hydrolyze of rice straw was estimated with treating dry rice straw and raw fiber by 60 Co γ-rays irradiation. the water-soluble deoxidize carbohydrate and total carbohydrate of 60 Co γ-rays irradiated rice straw and raw fibres were measured by DNS method and vitrol-phenol method. The changes of deoxidize carbohydrate groups of irradiated hydrolyzing rice straw were analyzed by gas chromatography. The organism structures of irradiated rice straw were scanned by electron microscope, the results showed that 1000-1500 kGy 60 Co γ-irradiation doses effectively destroyed rice straw's organism structures, especially the silicon crystal structures, and along with irradiation doses increased the breakage degree enlarged significantly. The contents of the water-soluble deoxidize carbohydrate and total carbohydrate of rice straw increased significantly. treated by both irradiation and enzyme, the cellulose transform rate of rice straw was 88.7%, which is better than that only treated by 60 Co γ-irradiation or enzyme. The content of water-solubility deoxidize carbohydrate of the treated rice straw was 214.4 mg/g and the total carbohydrate of straw was 758.5 mg/g. The contents of mannose, galactose, glucose, arabinose and xylose increased significantly, among those carbohydrate, the glucose's increment was the largest and account for 62.64%, and mannose's increments was the second. The contents of lignin of the rice straw were not influenced obviously by irradiation treatment. (authors)

Novel Alleviation Mechanisms of Aluminum Phytotoxicity via Released Biosilicon from Rice Straw-Derived Biochars

Science.gov (United States)

Qian, Linbo; Chen, Baoliang; Chen, Mengfang

2016-07-01

Replacing biosilicon and biocarbon in soil via biochar amendment is a novel approach for soil amelioration and pollution remediation. The unique roles of silicon (Si)-rich biochar in aluminum (Al) phytotoxicity alleviation have not been discovered. In this study, the alleviation of Al phytotoxicity to wheat plants (root tips cell death) by biochars fabricated from rice straw pyrolyzed at 400 and 700 °C (RS400 and RS700) and the feedstock (RS100) were studied using a slurry system containing typical acidic soils for a 15-day exposure experiment. The distributions of Al and Si in the slurry solution, soil and plant root tissue were monitored by staining methods, chemical extractions and SEM-EDS observations. We found that the biological sourced silicon in biochars served dual roles in Al phytotoxicity alleviation in acidic soil slurry. On one hand, the Si particles reduced the amount of soil exchangeable Al and prevented the migration of Al to the plant. More importantly, the Si released from biochars synchronously absorbed by the plants and coordinated with Al to form Al-Si compounds in the epidermis of wheat roots, which is a new mechanism for Al phytotoxicity alleviation in acidic soil slurry by biochar amendment. In addition, the steady release of Si from the rice straw-derived biochars was a sustainable Si source for aluminosilicate reconstruction in acidic soil.

GIS-based biomass resource utilization for rice straw cofiring in the Taiwanese power market

International Nuclear Information System (INIS)

Hu, Ming-Che; Huang, An-Lei; Wen, Tzai-Hung

2013-01-01

Rice straw, a rich agricultural byproduct in Taiwan, can be used as biomass feedstock for cofiring systems. In this study, we analyzed the penetration of rice straw cofiring systems in the Taiwanese power market. In the power generation system, rice straw is cofired with fossil fuel in existing electricity plants. The benefits of cofiring systems include increasing the use of renewable energy, decreasing the fuel cost, and lowering greenhouse gas emissions. We established a linear complementarity model to simulate the power market equilibrium with cofiring systems in Taiwan. GIS-based analysis was then used to analyze the geospatial relationships between paddy rice farms and power plants to assess potential biomass for straw-power generation. Additionally, a sensitivity analysis of the biomass feedstock supply system was conducted for various cofiring scenarios. The spatial maps and equilibrium results of rice straw cofiring in Taiwanese power market are presented in the paper. - Highlights: ► The penetration of straw cofiring systems in the power market is analyzed. ► GIS-based analysis assesses potential straw-power generation. ► The spatial maps and equilibrium results of rice straw cofiring are presented

Fate of Fertilizer-Derived N Applied to Enhance Rice Straw Decomposition in a Paddy Field during the Fallow Season under Cool Temperature Conditions

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Fumiaki Takakai

2018-03-01

Full Text Available A field experiment was conducted to evaluate the fate of nitrogen (N derived from fertilizer (fertilizer-derived N applied to a paddy field after rice harvesting to promote rice straw decomposition during the fallow season, and to determine its effect on soil N fertility in northern Japan. A frame containing soil mixed with rice straw and 15N-labeled fertilizer (4.3 g N m−2 ammonium sulfate [AS] or lime-nitrogen [LN] was placed into a paddy field on a gray lowland soil during the fallow season (October–April, and the following rice-growing season (May–September. Before cultivation (April, the percentages of fertilizer-derived N in soil + straw were higher for LN (55–72% than for AS (41–63%. At the harvesting stage (September, the percentages of fertilizer-derived N in plants were significantly higher for LN (4.9–6.2% than for AS (3.4–5.3%, and the percentages in soil were also significantly higher for LN (42–61% than for AS (31–38%. This could be attributed to the nitrification inhibitory effect of LN and result in the suppression of N losses via leaching. Consequently, fertilizer-derived N could contribute to the maintenance of soil N fertility, and this effect could be higher for LN than AS.

Biosorption of aqueous lead (II) on rice straws (oryza sativa) by flash column process

International Nuclear Information System (INIS)

Khalid, H.N.; Hassan, M.U.; Jamil, N.; Ahmad, D.; Bushra, H.; Khatoon, S.

2010-01-01

Biosorption of Pb (II) on rice straws has been studied with the variation in the parameters and on modified rice straws by flash column process. Different parameters like particle size of adsorbent, initial concentration of metal ions, length and width of columns were studied. A comparative study of modification of adsorbent was also done for which rice straws were modified with EDTA, acids, bases, and volatile organic solvents. Base modified adsorbents have shown an increase in adsorption capacity while acid modified adsorbents proved to be the poor adsorbents for metal ions similarly ash of rice straws used as adsorbent given higher adsorption and EDTA modified adsorbents have shown least adsorption of metal ions. Polar volatile organic solvents modified adsorbent gave less adsorption efficiency and non polar adsorbent shown no influence on Pb (II) uptake capacity of rice straws. Rice straws proved to be the best biosorbent for Pb(II) in aqueous solution. The biosorption characteristics fit well with Langmuir and Freundlich isotherm. (author)

Bioconversion of rice straw as animal feed ingredient through solid state fermentation

International Nuclear Information System (INIS)

Mohamad Hanif Mohamad Jamil; Sepiah Muid

1998-01-01

Work was conducted to establish procedures and techniques to utilise microorganisms, particularly basidiomycetes, for solid fermentation of rice by-products. The purpose of the study was to determine the potential of biologically processed rice by-products as ingredients of feed formula for selected livestock. Fungal organisms Auriculariapolytrichia, Lentimus connatus, L. edodes, Pleurotus cystidiosus, P. florida, P. sajor-caju and Volvariella volvacea respectively were inoculated on sterilised rice straw and the mycelium produced were cultured for periods of 3-4 weeks by which time the straw was fully enmeshed with mycelia. Proximate analysis of the finished products gave increases of 93-172 % crude protein and reduction of 31-54 % crude fibre on comparison with untreated rice straw. Amino acid analysis showed general increases for solid fermented rice straw (SFRS) which were comparatively close to amino acid values of conventional feed ingredients such as wheat, corn, sorghum and barley. Solid fermented rice straw was also tested as an ingredient in the formulation of rations for broiler chickens. Feeding trials on poultry indicated a maximum substitution of 50% maize with SFRS in feed rations was possible to attain acceptable growth of chickens to an average live final weight of 1.8 - 2.0 kg. per chicken at age 7 weeks. From studies undertaken, it was observed that the cellulolytic straw could be developed as a potential feed material for livestock through solid fermentation with microorganisms. From the research results, the use of solid fermented rice straw as an alternative ingredient in animal feeds may be one way in reducing reliance on feed imports and at the same time controlling environmental pollution. (Author)

An Inclusive Investigation on Conceivable Performance of Rice Straw Incinerated Electricity Generation

Science.gov (United States)

Bhattacharjee, Subhadeep; Mohanta, Subhajit

2018-03-01

Biomass energy is one of the potential renewable energy sources which occupy 77% of the available natural resources of the world. In India, agro residues constitute a major part of the total annual production of the biomass resource. Rice is the major crop in India that leaves substantial quantity of straw in the field. 34% of rice straw residue produced in the country is surplus and is either left in the field as uncollected or to a large extent open-field burnt. Thus, the unutilized rice straw is found promising for heat and power generation either through incineration (direct combustion) or thermo chemical conversion. This present work envisages the comprehensive performative evaluation of a rice straw supported biomass incineration power plant mainly through plant performance characterization, plant economics, and co-firing issues with emission analysis.

Intake and digestibility of untreated and urea treated rice straw base diet fed to sheep

Directory of Open Access Journals (Sweden)

D Yulistiani

2003-03-01

Full Text Available Rice straw as one of agricultural by-products has low quality due to low content of essensial nutrients like protein, energy, minerals and vitamin as well as poor palatability and digestibility. Therefore, the quality of rice straw needs to be improved in order to increase its utilization by gastrointestinal tract of ruminants. The purpose of this study is to compare untreated and urea treated rice straw as basal diets for sheep. Twelve mature Merino wethers (average body weight 53.62 + 3.44 kg were separated into 4 groups based on their live weight with each groups assigned three diets, that are: diet 1 untreated rice straw with high forage legume content, diet 2 urea ensiled rice straw and diet 3 rice straw sprayed with urea solution at feeding time. Diets were allocated based on a randomized complete block design. Urea ensiled rice straw was prepared by spraying chopped straw with urea solution to yield straw containing 4% urea and 40% moisture, then kept in air tight polythylene bags for 6 weeks. The untreated, ensiled and urea supplemented rice straw were mixed with other feed ingredients to provide isoenergetic and isonitrogenous diets. Diets were formulated to meet maintenance requirement according to NRC. Sheep were adapted to experimental diets for 15 days, and after adaptation period, a metabolism trial was conducted. Results reveal that dry matter intake permetabolic body weight (DMI/W0.75, DE (digestible energi intake and apparent digestibility of NDF (neutral detergent fibre were not significantly different between diet 1 and diet 2. Apparent digestibility of DM (dry matter, OM (organic matter, and ADF (acid detergent fibre, as well as N retention were not significantly different between three diets. Positive result in N retention was only observed in diet 2, while others were negative. It may be concluded from this study that untreated rice straw basal diet supplemented with forage legume offer an alternative method other than urea

Mutation of Cellulose Synthase Gene Improves the Nutritive Value of Rice Straw

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Yanjing Su

2012-06-01

Full Text Available Rice straw is an important roughage resource for ruminants in many rice-producing countries. In this study, a rice brittle mutant (BM, mutation in OsCesA4, encoding cellulose synthase and its wild type (WT were employed to investigate the effects of a cellulose synthase gene mutation on rice straw morphological fractions, chemical composition, stem histological structure and in situ digestibility. The morphological fractions investigation showed that BM had a higher leaf sheath proportion (43.70% vs 38.21%, p0.05 was detected in neutral detergent fiber (NDFom and ADL contents for both strains. Histological structure observation indicated that BM stems had fewer sclerenchyma cells and a thinner sclerenchyma cell wall than WT. The results of in situ digestion showed that BM had higher DM, NDFom, cellulose and hemicellulose disappearance at 24 or 48 h of incubation (p<0.05. The effective digestibility of BM rice straw DM and NDFom was greater than that of WT (31.4% vs 26.7% for DM, 29.1% vs 24.3% for NDFom, p<0.05, but the rate of digestion of the slowly digested fraction of BM rice straw DM and NDF was decreased. These results indicated that the mutation in the cellulose synthase gene could improve the nutritive value of rice straw for ruminants.

Effect of pH, temperature and moisture content during composting of rice straw burning at different temperature with food waste and effective microorganisms

Science.gov (United States)

Azura Zakarya, Irnis; Baya Khalib, Siti Noor; Ramzi, Norhasykin Mohd

2018-03-01

Rice straw is considered as one of the most important agricultural residues and represented as one of the major by-products from rice production process. Normally, rice straw that produced after harvesting season been directly burned on-farm. Conversion of rice straw into value added compost will improve the productivity of plant, reduction of pollution towards environment and reduction of local pollution due to open burning activity. The objective of this study was to evaluate the performance of composting rice straw ash (RSA) with food waste (FW) and effective microorganisms (EM) in term of the compost quality (pH, temperature, moisture content). RSA was prepared by burning the raw rice straw at three different temperature of 300°C, 400°C and 500°C for one hour. EM used during the composting process was prepared by mixing of brown sugar, `tempe' and water that can be used after one week of fermentation process. There are four treatments of RSA-compost; RSA (300°C), RSA (400°C), RSA (500°C) and control (raw rice straw) with the same amount of compost medium; 1kg black soil, 0.5kg RSA, 3L EM and 1kg FW. The composting process happens for 30 days. During the composting process, all the parameters of RSA-compost obtained in a range like; pH value 8-10, temperature 20-50°C and moisture content 40-60%. The result showed that all compost quality of rice straw ash compost obtained in an acceptable range for final compost to establish.

Influence of rice straw-derived dissolved organic matter on lactic acid fermentation by Rhizopus oryzae.

Science.gov (United States)

Chen, Xingxuan; Wang, Xiahui; Xue, Yiyun; Zhang, Tian-Ao; Li, Yuhao; Hu, Jiajun; Tsang, Yiu Fai; Zhang, Hongsheng; Gao, Min-Tian

2018-01-31

Rice straw can be used as carbon sources for lactic acid fermentation. However, only a small amount of lactic acid is produced even though Rhizopus oryzae can consume glucose in rice straw-derived hydrolysates. This study correlated the inhibitory effect of rice straw with rice straw-derived dissolved organic matter (DOM). Lactic acid fermentations with and without DOM were conducted to investigate the effect of DOM on lactic acid fermentation by R. oryzae. Fermentation using control medium with DOM showed a similar trend to fermentation with rice straw-derived hydrolysates, showing that DOM contained the major inhibitor of rice straw. DOM assay indicated that it mainly consisted of polyphenols and polysaccharides. The addition of polyphenols and polysaccharides derived from rice straw confirmed that lactic acid fermentation was promoted by polysaccharides and significantly inhibited by polyphenols. The removal of polyphenols also improved lactic acid production. However, the loss of polysaccharides during the removal of polyphenols resulted in low glucose consumption. This study is the first to investigate the effects of rice straw-derived DOM on lactic acid fermentation by R. oryzae. The results may provide a theoretical basis for identifying inhibitors and promoters associated with lactic acid fermentation and for establishing suitable pretreatment methods. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Rice straw addition as sawdust substitution in oyster mushroom (Pleurotus ostreatus) planted media

Science.gov (United States)

Utami, Christine Pamardining; Susilawati, Puspita Ratna

2017-08-01

Oyster mushroom is favorite by the people because of the high nutrients. The oyster mushroom cultivation usually using sawdust. The availability of sawdust become difficult to find. It makes difficulties of mushroom cultivation. Rice straw as an agricultural waste can be used as planted media of oyster mushroom because they contain much nutrition needed to the mushroom growth. The aims of this research were to analysis the influence of rice straw addition in a baglog as planted media and to analysis the concentration of rice straw addition which can substitute sawdust in planted media of oyster mushroom. This research used 4 treatment of sawdust and rice straw ratio K = 75 % : 0 %, P1 = 60 % : 15 %, P2 = 40 % : 35 %, P3 = 15 % : 60 %. The same material composition of all baglog was bran 20%, chalk 5%, and water 70%. The parameters used in this research were wet weight, dry weight, moisture content and number of the mushroom fruit body. Data analysis was used ANOVA test with 1 factorial. The results of this research based on statistical analysis showed that there was no influence of rice straw addition in a planted media on the oyster mushroomgrowth. 15% : 60% was the concentrationof rice straw additionwhich can substitute the sawdust in planted media of oyster mushroom.

[Effects of simulated acid rain on decomposition of soil organic carbon and crop straw].

Science.gov (United States)

Zhu, Xue-Zhu; Huang, Yao; Yang, Xin-Zhong

2009-02-01

To evaluate the effects of acid rain on the organic carbon decomposition in different acidity soils, a 40-day incubation test was conducted with the paddy soils of pH 5.48, 6.70 and 8.18. The soils were amended with 0 and 15 g x kg(-1) of rice straw, adjusted to the moisture content of 400 g x kg(-1) air-dried soil by using simulated rain of pH 6.0, 4.5, and 3.0, and incubated at 20 degrees C. The results showed that straw, acid rain, and soil co-affected the CO2 emission from soil system. The amendment of straw increased the soil CO2 emission rate significantly. Acid rain had no significant effects on soil organic carbon decomposition, but significantly affected the straw decomposition in soil. When treated with pH 3.0 acid rain, the amount of decomposed straw over 40-day incubation in acid (pH 5.48) and alkaline (pH 8.18) soils was 8% higher, while that in neutral soil (pH 6.70) was 15% lower, compared to the treatment of pH 6.0 rain. In the treatment of pH 3.0 acid rain, the decomposition rate of soil organic C in acid (pH 5.48) soil was 43% and 50% (P pH 6.70) and alkaline (pH 8.18) soils, while the decomposition rate of straw in neutral soil was 17% and 16% (P < 0.05) lower than that in acid and alkaline soils, respectively.

Efficient Hydrolysis of Rice Straw into Xylose and Glucose by a Two-step Process

Directory of Open Access Journals (Sweden)

YAN Lu-lu

2016-07-01

Full Text Available The hydrolysis of rice straw into xylose and glucose in dilute sulfuric acid aqueous solution was studied with a two-step process in batch autoclave reactor. The results showed that compared with the traditional one-step acid hydrolysis, both xylose and glucose could be produced in high yields from rice straw by using the two-step acid hydrolysis process. The effects of reaction temperature, reaction time, the amount of rice straw and acid concentration on the hydrolysis of rice straw were systematically studied, and showed that except initial rice straw loading amount, the other parameters had remarkable influence on the products distribution and yields. In the first-step of the hydrolysis process, a high xylose yield of 162.6 g·kg-1 was obtained at 140℃ after 120 min reaction time. When the solid residues from the first step were subjected to a second-step hydrolysis, a glucose yield as high as 216.5 g·kg-1 could be achieved at 180℃ after 120 min. This work provides a promising strategy for the efficient and value-added utilization of agricultural wastes such as rice straw.

Effect of integrating straw into agricultural soils on soil infiltration and evaporation.

Science.gov (United States)

Cao, Jiansheng; Liu, Changming; Zhang, Wanjun; Guo, Yunlong

2012-01-01

Soil water movement is a critical consideration for crop yield in straw-integrated fields. This study used an indoor soil column experiment to determine soil infiltration and evaporation characteristics in three forms of direct straw-integrated soils (straw mulching, straw mixing and straw inter-layering). Straw mulching is covering the land surface with straw. Straw mixing is mixing straw with the top 10 cm surface soil. Then straw inter-layering is placing straw at the 20 cm soil depth. There are generally good correlations among the mulch integration methods at p soil infiltration, followed by straw mulching. Due to over-burden weight-compaction effect, straw inter-layering somehow retarded soil infiltration. In terms of soil water evaporation, straw mulching exhibited the best effect. This was followed by straw mixing and then straw inter-layering. Straw inter-layering could have a long-lasting positive effect on soil evaporation as it limited the evaporative consumption of deep soil water. The responses of the direct straw integration modes to soil infiltration and evaporation could lay the basis for developing efficient water-conservation strategies. This is especially useful for water-scarce agricultural regions such as the arid/semi-arid regions of China.

Efficient bioconversion of rice straw to ethanol with TiO2/UV pretreatment.

Science.gov (United States)

Kang, Hee-Kyoung; Kim, Doman

2012-01-01

Rice straw is a lignocellulosic biomass that constitutes a renewable organic substance and alternative source of energy; however, its structure confounds the liberation of monosaccharides. Pretreating rice straw using a TiO(2)/UV system facilitated its hydrolysis with Accellerase 1000(™), suggesting that hydroxyl radicals (OH·) from the TiO(2)/UV system could degrade lignin and carbohydrates. TiO(2)/UV pretreatment was an essential step for conversion of hemicellulose to xylose; optimal conditions for this conversion were a TiO(2) concentration of 0.1% (w/v) and an irradiation time of 2 h with a UV-C lamp at 254 nm. After enzymatic hydrolysis, the sugar yields from rice straw pretreated with these parameters were 59.8 ± 0.7% of the theoretical for glucose (339 ± 13 mg/g rice straw) and 50.3 ± 2.8% for xylose (64 ± 3 mg/g rice straw). The fermentation of enzymatic hydrolysates containing 10.5 g glucose/L and 3.2 g xylose/L with Pichia stipitis produced 3.9 g ethanol/L with a corresponding yield of 0.39 g/g rice straw. The maximum possible ethanol conversion rate is 76.47%. TiO(2)/UV pretreatment can be performed at room temperature and atmospheric pressure and demonstrates potential in large-scale production of fermentable sugars.

Effect of pH, temperature and moisture content during composting of rice straw burning at different temperature with food waste and effective microorganisms

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Zakarya Irnis Azura

2018-01-01

Full Text Available Rice straw is considered as one of the most important agricultural residues and represented as one of the major by-products from rice production process. Normally, rice straw that produced after harvesting season been directly burned on-farm. Conversion of rice straw into value added compost will improve the productivity of plant, reduction of pollution towards environment and reduction of local pollution due to open burning activity. The objective of this study was to evaluate the performance of composting rice straw ash (RSA with food waste (FW and effective microorganisms (EM in term of the compost quality (pH, temperature, moisture content. RSA was prepared by burning the raw rice straw at three different temperature of 300°C, 400°C and 500°C for one hour. EM used during the composting process was prepared by mixing of brown sugar, ‘tempe’ and water that can be used after one week of fermentation process. There are four treatments of RSA-compost; RSA (300°C, RSA (400°C, RSA (500°C and control (raw rice straw with the same amount of compost medium; 1kg black soil, 0.5kg RSA, 3L EM and 1kg FW. The composting process happens for 30 days. During the composting process, all the parameters of RSA-compost obtained in a range like; pH value 8-10, temperature 20-50°C and moisture content 40-60%. The result showed that all compost quality of rice straw ash compost obtained in an acceptable range for final compost to establish.

Additives on in vitro ruminal fermentation characteristics of rice straw

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Vanessa Peripolli

Full Text Available ABSTRACT The objective of this study was to evaluate the effects of mineral and protein-energy (MPES, exogenous fibrolytic enzyme supplements (ES, combination of MPES + ES, and straw without supplement (WS on digestibility, fermentation kinetic parameters, cumulative gas production, methane, CO2 production, and volatile fatty acid concentration of rice straw of low and high nutritional value, estimated by in vitro techniques. The experimental design was randomized and factorial 2 × 4: two straws (low and high nutritional value incubated with four supplements (MPES, ES, MPES + ES, and WS and their interactions. Four experimental periods were used, totaling four replications per treatment over time. Data were analyzed by PROC MIXED of SAS. The in vitro dry matter and organic matter digestibilities of the rice straw with high nutritional value was improved by MPES, while the combination of MPES + ES supplements inhibited the digestibility of this straw. Dietary carbohydrate and nitrogen increased through MPES and MPES + ES supplements resulted in an increase in NH3-N concentration and a decrease in CO2 production due to the microbial mass formation. However, this increase was not enough to improve organic matter degradability parameters, cummulative gas production, gas production kinetics, and acetate:propionate ratio and reduce methane emissions. The straw with high nutritional value showed greater content of nitrogen fraction a, effective degradability, cummulative gas production, and methane and CO2 productions comparing with low-nutritional value straw. The use of MPES and MPES + ES supplements can be used as strategy to mitigate CO2 in ruminant production systems that use rice straw.

Fermentation of Rice Straw Uses Mix Inoculum of Anaerobe Facultative Bacteria Isolate from Buffalo Rumen

International Nuclear Information System (INIS)

Sasongko, W. T.; Irawan Sugoro

2004-01-01

Rice straw quality could be increased as feed by fermentation which has been mixed with bacteria inoculum from buffalo rumen. This experiment used rice straw from Atomita 4, four treatments and one control, i.e. A (rice straw, molasses 5 %, urea 5 %, and inoculum 10 %), B (rice straw, molasses 5 %, and urea 5 %), C (rice straw, molasses 5 %, and inoculum 10 %), D (rice straw and molasses 5 %), and K (control) have been used in this experiment. The parameters were digestibility of dry matter and organic matter, VFA, ammonia and in vitro gas production. The result, showed that the highest gas production, dry matter and organic matter digestibility occurred on A i.e. 17.48 ml/200 mg, 57.78%, and 52.39 %. The highest ammonia occurred on D (32.99 mg/100 ml) and the highest VFA occurred on C (12.36 mmol/100 ml). The concentration of ammonia and VFA of A significant to treatment of D and C). It may be concluded that the A treatment is the best and have potency to be develop. (author)

The effects of gamma irradiation in combination with NaCl treatment on digestibility of rice straw

International Nuclear Information System (INIS)

Abidin, Z.; Suharyono.

1988-01-01

Combination of gamma irradiation and sodiumchloride treatments have been conducted to increase the nutritive value of rice straw as an animal feed. Rice straw was sprayed by sodiumchloride solution prior to gamma irradiation. The sodiumchloride concentration in straw were 0, 1, and 2% ( gNaCl/100 g rice straw), and irradiation dose were 0, 5, 10, and 15 Mrad. Result indicated that the combined treatments significantly increased (p<0.01) dry matter digestibility of rice straw. On the other hand, there was no significant interaction between gamma irradiation and sodiumchloride treatment was observed. (authors). 11 refs, 4 tabs

The kinetics of glucose production from rice straw by Aspergillus niger

African Journals Online (AJOL)

In this investigation, glucose was produced from rice straw using cells of Aspergillus niger, isolated from maize grain. Glucose yield was found to increase from 43 to 87% as the rice straw particle size decreased from 425 to 75 ìm, while the optimal temperature and pH were found within the range of 45 - 50°C and 4.5 - 5 ...

Solid-state fermentation of rice straw residues for its use as growing medium in ornamental nurseries

Science.gov (United States)

Belal, Elsayed B.; El-Mahrouk, M. E.

2010-11-01

This work was conducted at a private nursery in Kafr El-Sheikh governorate to investigate the bioconversion of rice straw into a soil-like substrate (SLS) by Phanerochaete chrysosporium and Trichoderma hazianum and the possibility of using rice straw compost in ornamental nurseries as a partial or total replacement of coconut peat (CP) and vermiculite (V) in the growing medium. The results showed that rice straw could be treated better by aerobic fermentation. The authors used five mixtures as follows: (1) Control (CP+V at 1:1 v/v), (2) SLS (100%), (3) SLS+CP (1:1 v/v), (4) SLS+V (1:1 v/v), and (5) SLS+CP+V (1:1:1 v/v/v). Data were recorded as seedling height, no. of leaves, shoot fresh and dry weights, root length and root fresh and dry weights in order to assess the quality of both transplants of Althea rosea (hollyhock) and Calendula officinalis (scotch marigold). Hollyhock seedlings grown in medium containing a mixture of SLS+CP+V displayed quality traits similar to those recorded from the control treatment, while scotch marigold seedlings in the same medium followed the control medium in quality.

Influence of moisture content, particle size and forming temperature on productivity and quality of rice straw pellets

Energy Technology Data Exchange (ETDEWEB)

Ishii, Kazuei, E-mail: k-ishii@eng.hokudai.ac.jp; Furuichi, Toru

2014-12-15

Highlights: • Optimized conditions were determined for the production of rice straw pellets. • The moisture content and forming temperature are key factors. • High quality rice pellets in the lower heating value and durability were produced. - Abstract: A large amount of rice straw is generated and left as much in paddy fields, which causes greenhouse gas emissions as methane. Rice straw can be used as bioenergy. Rice straw pellets are a promising technology because pelletization of rice straw is a form of mass and energy densification, which leads to a product that is easy to handle, transport, store and utilize because of the increase in the bulk density. The operational conditions required to produce high quality rice straw pellets have not been determined. This study determined the optimal moisture content range required to produce rice straw pellets with high yield ratio and high heating value, and also determined the influence of particle size and the forming temperature on the yield ratio and durability of rice straw pellets. The optimal moisture content range was between 13% and 20% under a forming temperature of 60 or 80 °C. The optimal particle size was between 10 and 20 mm, considering the time and energy required for shredding, although the particle size did not significantly affect the yield ratio and durability of the pellets. The optimized conditions provided high quality rice straw pellets with nearly 90% yield ratio, ⩾12 MJ/kg for the lower heating value, and >95% durability.

Influence of moisture content, particle size and forming temperature on productivity and quality of rice straw pellets

International Nuclear Information System (INIS)

Ishii, Kazuei; Furuichi, Toru

2014-01-01

Highlights: • Optimized conditions were determined for the production of rice straw pellets. • The moisture content and forming temperature are key factors. • High quality rice pellets in the lower heating value and durability were produced. - Abstract: A large amount of rice straw is generated and left as much in paddy fields, which causes greenhouse gas emissions as methane. Rice straw can be used as bioenergy. Rice straw pellets are a promising technology because pelletization of rice straw is a form of mass and energy densification, which leads to a product that is easy to handle, transport, store and utilize because of the increase in the bulk density. The operational conditions required to produce high quality rice straw pellets have not been determined. This study determined the optimal moisture content range required to produce rice straw pellets with high yield ratio and high heating value, and also determined the influence of particle size and the forming temperature on the yield ratio and durability of rice straw pellets. The optimal moisture content range was between 13% and 20% under a forming temperature of 60 or 80 °C. The optimal particle size was between 10 and 20 mm, considering the time and energy required for shredding, although the particle size did not significantly affect the yield ratio and durability of the pellets. The optimized conditions provided high quality rice straw pellets with nearly 90% yield ratio, ⩾12 MJ/kg for the lower heating value, and >95% durability

Impact of rice-straw biochars amended soil on the biological Si cycle in soil-plant ecosystem

Science.gov (United States)

Li, Zimin; Delvaux, Bruno; Struyf, Eric; Unzué-Belmonte, Dácil; Ronsse, Frederik; Cornelis, Jean-Thomas

2017-04-01

Biochar used as soil amendment can enhance soil fertility and plant growth. It may also contribute to increase the plant mineralomass of silicon (Si). However, very little studies have focused on the plant Si cycling in biochar amended soils. Here, we study the impact of two contrasting biochars derived from rice straws on soil Si availability and plant Si uptake. Rice plants were grown in a hydroponic device using Yoshida nutrient solution, respectively devoid of H4SiO4 (0 ppm Si: Si-) and enriched with it (40 ppm Si: Si+). After 12 weeks, the plants were harvested for further pyrolysis, conducted with holding time of 1h at 500˚ C. The respective rice-biochars are Si-/biochar and Si+/biochar. They exhibit contrasting phytolith contents (0.3 g Si kg-1 vs. 51.3 g Si kg-1), but identical physico-chemical properties. They were applied in two soils differing in weathering stage: a weathered Cambisol (CA) and a highly weathered Nitisol (NI). We then studied the effects of the amended biochar on CaCl2 extractable Si using a 64-days kinetic approach, on the content of soil biogenic Si, and on the uptake of Si by wheat plants grown for 5 weeks. We also quantified Si mineralomass in plants. We compared the effects of biochars to that of wollastonite (Wo)-(CaSiO3), a common Si-fertilizer. Our results show that Si+/biochar significantly increase the content of BSi in both soils. In CA, the cumulative content of CaCl2 extractable Si amounts to 85 mg kg-1 after Si+/biochar amendment, which is below the amount extracted after Wo application (100 mg kg-1). In contrast, in NI, the cumulative content of CaCl2 extractable Si is 198 mg kg-1 in the Si+/biochar amended treatment, which is far above the one measured after Wo application (93 mg kg-1). The Si-/biochar has no effect on the cumulative content of CaCl2 extractable Si in either soil type. Biochars and wollastonite increase the biomass of wheat on both soils. The increase is, however, larger in NI than in CA. In terms of Si

Effects of Aspergillus niger (K8) on nutritive value of rice straw ...

African Journals Online (AJOL)

The objective of this study was to evaluate the use of solid state fermentation for the improvement of the quality of rice straw as animal feed. Rice straw was fermented using Aspergillus niger (K8) with and without additional nitrogen source (urea). Cellulose, hemicelluloses, organic matter (OM), dry matter (DM), acid ...

COMPARISON OF TWO CHEMICAL PRETREATMENTS OF RICE STRAW FOR BIOGAS PRODUCTION BY ANAEROBIC DIGESTION

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Zilin Song,

2012-06-01

Full Text Available Lignocellulosic biomass is considered the most abundant renewable resource that has the potential to contribute remarkably in the supply of biofuel. Previous studies have shown that chemical pretreatment prior to anaerobic digestion (AD can increase the digestibility of lignocellulosic biomass and methane yield. In the present study, the effect of rice straw pretreatment using ammonium hydroxide (NH3•H2O and hydrogen peroxide (H2O2 on the biogasification performance through AD was investigated. A self-designed, laboratory-scale, and continuous anaerobic biogas digester was used for the evaluation. Results showed that the contents of the rice straw, i.e. the lignin, cellulose, and hemicellulose were degraded significantly after the NH3•H2O and H2O2 treatments, and that biogas production from all pretreated rice straw increased. In addition, the optimal treatments for biogas production were the 4% and 3% H2O2 treatments (w/w, which yielded 327.5 and 319.7 mL/gVS, biogas, respectively, higher than the untreated sample. Biogas production from H2O2 pretreated rice straw was more favorable than rice straw pretreated with same concentration of ammonia, ranking in the order of 4% ≈ 3% > 2% > 1%. The optimal amount of H2O2 treatment for rice straw biogas digestion is 3% when economics and biogas yields are considered.

Chemical composition and utilization of rice straw by goats in Malaysia

International Nuclear Information System (INIS)

Tuen, A.A.; Mahyuddin Dahan, M.

1991-01-01

Three experiments were conducted to assess the nutritive value of various types of rice straw for use by goats. In Experiment 1, four varieties of rice straw were exposed to heavy rain and sunshine for 10 days to assess the change in chemical composition and degradation in the rumen. The exposure led to a reduction in the contents of nitrogen and phosphorus. The degradation in the rumen of the samples exposed to the above weather conditions varied from 20.9 to 34.5%. In Experiment 2, the intake and digestion of untreated, urea supplemented, and urea treated rice straw of unknown variety were investigated using six male goats. Treating with urea resulted in significantly higher intake (p 3 ) and volatile fatty acid (VFA) concentrations and negative N retention were obtained when the goats were fed on untreated straw. With urea treated straw, however, higher concentrations of NH 3 and VFAs and positive N retention were obtained. From the isotope dilution measurement it was observed that the amount of dietary P absorbed was significantly (p < 0.05) higher in goats fed untreated straw than in those fed urea treated straw. In Experiment 3, the rate of passage of small particles through the digestive tract of goats fed the diets in Experiment 2 was measured. The mean rumen retention time ranged from 31.2 to 38.7 h. Although not significantly different, there was a tendency for the transit time to be longer in goats fed the urea treated straw than those on other diets. 43 refs, 2 figs, 7 tabs

Air pollutant emissions from rice straw open field burning in India, Thailand and the Philippines

International Nuclear Information System (INIS)

Gadde, Butchaiah; Bonnet, Sebastien; Menke, Christoph; Garivait, Savitri

2009-01-01

Rice is a widely grown crop in Asia. China (30%) and India (21%) contribute to about half of the world's total rice production. In this study, three major rice-producing countries in Asia are considered, India, Thailand and the Philippines (the later two contributing 4% and 2% of the world's rice production). Rice straw is one of the main field based residues produced along with this commodity and its applications vary widely in the region. Although rice production practises vary from one country to another, open burning of straw is a common practice in these countries. In this study, an approach was followed aiming at (a) determining the quantity of rice straw being subject to open field burning in those countries, (b) congregating pollutant specific emissions factors for rice straw burning, and (c) quantifying the resulting air pollutant emissions. Uncertainties in the results obtained as compared to a global approach are also discussed. - This research work contributes to enhance scientific knowledge for estimating air pollutant emissions from open burning of crop residues and improve emission results accuracy.

Co-pyrolysis of rice straw and polypropylene using fixed-bed pyrolyzer

Science.gov (United States)

Izzatie, N. I.; Basha, M. H.; Uemura, Y.; Mazlan, M. A.; Hashim, M. S. M.; Amin, N. A. M.; Hamid, M. F.

2016-11-01

The present work encompasses the impact of temperature (450, 500, 550, 600 °C) on the properties of pyrolysis oil and on other product yield for the co-pyrolysis of Polypropylene (PP) plastics and rice straw. Co-pyrolysis of PP plastic and rice straw were conducted in a fixed-bed drop type pyrolyzer under an inert condition to attain maximum oil yield. Physically, the pyrolysis oil is dark-brown in colour with free flowing and has a strong acrid smell. Copyrolysis between these typically obtained in maximum pyrolysis oil yields up to 69% by ratio 1:1 at a maximum temperature of 550 °C. From the maximum yield of pyrolysis oil, characterization of pyrolysis product and effect of biomass type of the composition were evaluated. Pyrolysis oil contains a high water content of 66.137 wt.%. Furfural, 2- methylnaphthalene, tetrahydrofuran (THF), toluene and acetaldehyde were the major organic compounds found in pyrolysis oil of rice straw mixed with PP. Bio-char collected from co-pyrolysis of rice straw mixed with PP plastic has high calorific value of 21.190 kJ/g and also carbon content with 59.02 wt.% and could contribute to high heating value. The non-condensable gases consist of hydrogen, carbon monoxide, and methane as the major gas components.

Utilization of crops residues as compost and biochar for improving soil physical properties and upland rice productivity

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J. Barus

2016-07-01

Full Text Available The abundance of crops waste in the agricultural field can be converted to organic fertilizer throughout the process of composting or pyrolysis to return back into the soil. The study aimed to elucidate the effect of compost and biochar application on the physical properties and productivity of upland rice at Village of Sukaraja Nuban, Batanghari Nuban Sub district, East Lampung Regency in 2015. The amendment treatments were A. control; B. 10 t rice husk biochar/ ha; C. 10 t maize cob biochar/ha; D. 10 t straw compost/ha; E. 10 t stover compost/ha, F. 10 t rice husk biochar/ha + 10 t straw compost/ha; F. 10 t maize cob biochar/ha + 10 t maize stover compost/ha. The treatments were arranged in randomized block design with four replicates. The plot size for each treatment was 10 x 20 m. After incubation for about one month, undisturbed soil samples were taken using copper ring at 10–20 cm depth for laboratory analyzes. Analyses of soil physical properties included bulk density, particle density, total porosity, drainage porosity, and soil water condition. Plant observations conducted at harvest were plant height, number of panicle, number of grain/panicle, and grain weight/plot. Results of the study showed that biochar and compost improved soil physical properties such as bulk density, total porosity, fast drainage pores, water content, and permeability of soil. The combination of rice husk biochar and straw compost gave better effect than single applications on rice production components (numbers of panicle and grains of rice, and gave the highest yield of 4.875 t/ha.

Cry1Ab protein from Bt transgenic rice does not residue in rhizosphere soil

International Nuclear Information System (INIS)

Wang Haiyan; Ye Qingfu; Wang Wei; Wu Licheng; Wu Weixiang

2006-01-01

Expression of Cry1Ab protein in Bt transgenic rice (KMD) and its residue in the rhizosphere soil during the whole growth in field, as well as degradation of the protein from KMD straw in five soils under laboratory incubation were studied. The residue of Cry1Ab protein in KMD rhizosphere soil was undetectable (below the limit of 0.5 ng/g air-dried soil). The Cry1Ab protein contents in the shoot and root of KMD were 3.23-8.22 and 0.68-0.89 μg/g (fresh weight), respectively. The half-lives of the Cry1Ab protein in the soils amended with KMD straw (4%, w/w) ranged from 11.5 to 34.3 d. The residence time of the protein varied significantly in a Fluvio-marine yellow loamy soil amended with KMD straw at the rate of 3, 4 and 7%, with half-lives of 9.9, 13.8 and 18 d, respectively. In addition, an extraction method for Cry1Ab protein in soil was developed, with extraction efficiencies of 46.4-82.3%. - Cry1Ab protein was not detected in the rhizosphere soil of field-grown Bt transgenic rice

Bioconversion process of rice straw by thermotolerant cellulolytic ...

African Journals Online (AJOL)

Administrator

2011-09-26

state fermentation for bioethanol production is a focus of current attention. ... Optimization of fermentation conditions showed highest cellulolytic enzymes ... using dilute acid pretreated rice straw hydrolysate with initial soluble ...

Rumen Fermentation and Performance of Lactating Dairy Cows Affected by Physical Forms and Urea Treatment of Rice Straw

Directory of Open Access Journals (Sweden)

P. Gunun

2013-09-01

Full Text Available The aim of this study was to determine the effect of different physical forms and urea treatment of rice straw on feed intake, rumen fermentation, and milk production. Four, multiparous Holstein crossbred dairy cows in mid-lactation with initial body weight (BW of 409±20 kg were randomly assigned according to a 4×4 Latin square design to receive four dietary treatments. The dietary treatments were as follows: untreated, long form rice straw (LRS, urea-treated (5%, long form rice straw (5% ULRS, urea-treated (2.5%, long form rice straw (2.5% ULRS and urea-treated (2.5%, chopped (4 cm rice straw (2.5% UCRS. Cows were fed with concentrate diets at a ratio of concentrate to milk yield of 1:2 and rice straw was fed ad libitum. The findings revealed significant improvements in total DM intake and digestibility by using long and short forms of urea-treated rice straw (p0.05, whereas ruminal NH3-N, BUN and MUN were found to be increased (p<0.01 by urea-treated rice straw as compared with untreated rice straw. Volatile fatty acids (VFAs concentrations especially those of acetic acid were decreased (p<0.05 and those of propionic acid were increased (p<0.05, thus acetic acid:propionic acid was subsequently lowered (p<0.05 in cows fed with long or short forms of urea-treated rice straw. The 2.5% ULRS and 2.5% UCRS had greater microbial protein synthesis and was greatest when cows were fed with 5% ULRS. The urea-treated rice straw fed groups had increased milk yield (p<0.05, while lower feed cost and greater economic return was in the 2.5% ULRS and 2.5% UCRS (p<0.01. From these results, it could be concluded that 2.5% ULRS could replace 5% ULRS used as a roughage source to maintain feed intake, rumen fermentation, efficiency of microbial protein synthesis, milk production and economical return in mid-lactating dairy cows.

The influence of pH and organic matter content in paddy soil on heavy metal availability and their uptake by rice plants

Energy Technology Data Exchange (ETDEWEB)

Zeng Fanrong; Ali Shafaqat; Zhang Haitao [Department of Agronomy, College of Agriculture and Biotechnology, Huajiachi Campus, Zhejiang University, Hangzhou 310029 (China); Ouyang Younan [China National Rice Research Institute, Fuyang 310041 (China); Qiu Boyin; Wu Feibo [Department of Agronomy, College of Agriculture and Biotechnology, Huajiachi Campus, Zhejiang University, Hangzhou 310029 (China); Zhang Guoping, E-mail: zhanggp@zju.edu.c [China National Rice Research Institute, Fuyang 310041 (China)

2011-01-15

The experiments were done to investigate the effect of soil pH and organic matter content on EDTA-extractable heavy metal contents in soils and heavy metal concentrations in rice straw and grains. EDTA-extractable Cr contents in soils and concentrations in rice tissues were negatively correlated with soil pH, but positively correlated with organic matter content. The combination of soil pH and organic matter content would produce the more precise regression models for estimation of EDTA-Cu, Pb and Zn contents in soils, demonstrating the distinct effect of the two factors on the availability of these heavy metals in soils. Soil pH greatly affected heavy metal concentrations in rice plants. Furthermore, inclusion of other soil properties in the stepwise regression analysis improved the regression models for predicting straw Fe and grain Zn concentrations, indicating that other soil properties should be taken into consideration for precise predicting of heavy metal concentrations in rice plants. - Soil pH and organic matter content significantly affect heavy metal availability and accumulation in rice plants.

Phytoremediation of arsenic contaminated soil by Pteris vittata L. II. Effect on arsenic uptake and rice yield.

Science.gov (United States)

Mandal, Asit; Purakayastha, T J; Patra, A K; Sanyal, S K

2012-07-01

A greenhouse experiment evaluated the effect of phytoextraction of arsenic from a contaminated soil by Chinese Brake Fern (Pteris vittata L.) and its subsequent effects on growth and uptake of arsenic by rice (Oryza sativa L.) crop. Pteris vittata was grown for one or two growing cycles of four months each with two phosphate sources, using single super phosphate (SSP) and di-ammonium phosphate (DAP). Rice was grown on phytoextracted soils followed by measurements of biomass yield (grain, straw, and root), arsenic concentration and, uptake by individual plant parts. The biomass yield (grain, straw and rice) of rice was highest in soil phytoextracted with Pteris vittata grown for two cycles and fertilized with diammonium phosphate (DAP). Total arsenic uptake in contaminated soil ranged from 8.2 to 16.9 mg pot(-1) in first growing cycle and 5.5 to 12.0 mg pot(-1) in second growing cycle of Pteris vittata. There was thus a mean reduction of 52% in arsenic content of rice grain after two growing cycle of Pteris vittata and 29% after the one growing cycle. The phytoextraction of arsenic contaminated soil by Pteris vittata was beneficial for growing rice resulted in decreased arsenic content in rice grain of <1 ppm. There was a mean improvement in rice grain yield 14% after two growing cycle and 8% after the one growing cycle of brake fern.

Mechanisms of the stimulatory effects of rhamnolipid biosurfactant on rice straw hydrolysis

Energy Technology Data Exchange (ETDEWEB)

Zhang, Qiuzhuo; He, Guofu; Xu, Yatong [Department of Environmental Science, East China Normal University, 3663 North Zhongshan Road, Putuo District, Shanghai 200062 (China); Wang, Juan [Department of Environmental Science and Engineering, Harbin Institute of Technology, Harbin 150090 (China); Cai, Weimin [Department of Environmental Science and Engineering, Harbin Institute of Technology, Harbin 150090 (China); School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)

2009-11-15

Rhamnolipid biosurfactant, as an addition to rice straw hydrolysis bioprocess, could not only stimulate the hydrolysis rate, but also reduce the requirement for large amount of cellulases and promote its recycling process. In this article, through the observation of the changes of cellulases, microorganism, substrate and their mutual functions, the mechanisms of the stimulatory effect of rhamnolipid on rice straw hydrolysis were investigated. The study found that the addition of rhamnolipid increases the activity of {beta}-glucosidase but stabilizes Cel7A activity. The observed results might be the main mechanisms triggering the stimulatory effect of adding biosurfactants on rice straw hydrolysis. Meanwhile, zeta potential of the substrate increased, which could make the resistance of the cell attached to the substrate weaker. This in turn could facilitate easy adhesion and better retention of the microbial cell in the media. Moreover, we discovered that lignin content played an important role in the stimulatory effect of adding rhamnolipid. The adsorption of rhamnolipid biosurfactant prevented unproductive binding of enzymes to lignin. This could be another important mechanism responsible for the stimulatory effects of adding rhamnolipid on rice straw hydrolysis. (author)

Effect of Crop-Straw Derived Biochars on Pb(II) Adsorption in Two Variable Charge Soils

Institute of Scientific and Technical Information of China (English)

JIANG Tian-yu; XU Ren-kou; GU Tian-xia; JIANG Jun

2014-01-01

Two variable charge soils were incubated with biochars derived from straws of peanut, soybean, canola, and rice to investigate the effect of the biochars on their chemical properties and Pb(II) adsorption using batch experiments. The results showed soil cation exchange capacity (CEC) and pH signiifcantly increased after 30 d of incubation with the biochars added. The incorporation of the biochars markedly increased the adsorption of Pb(II), and both the electrostatic and non-electrostatic adsorption mechanisms contributed to Pb(II) adsorption by the variable charge soils. Adsorption isotherms illustrated legume-straw derived biochars more greatly increased Pb(II) adsorption on soils through the non-electrostatic mechanism via the formation of surface complexes between Pb(II) and acid functional groups of the biochars than did non-legume straw biochars. The adsorption capacity of Pb(II) increased, while the desorption amount slightly decreased with the increasing suspension pH for the studied soils, especially in a high suspension pH, indicating that precipitation also plays an important role in immobilizing Pb(II) to the soils.

Lead accumulation in the straw mushroom, Volvariella volvacea, from lead contaminated rice straw and stubble.

Science.gov (United States)

Kumhomkul, Thapakorn; Panich-pat, Thanawan

2013-08-01

Straw mushrooms were grown on lead contaminated rice straw and stubble. Study materials were dried, acid digested, and analyzed for lead using flame atomic absorption spectrophotometry. The results showed the highest lead concentration in substrate was 445.350 mg kg⁻¹ in Treatment 3 (T3) and the lowest was BD (below detection) in Treatment 1 (T1). The maximum lead content in straw mushrooms was 5.072 mg kg⁻¹ dw in pileus of T3 and the minimum lead content in straw mushrooms was BD in egg and mature (stalk and pileus) stage of T1. The lead concentration in straw mushrooms was affected by the age of the mycelium and the morphology of mushrooms. Mushrooms' lead uptake produced the highest accumulation in the cell wall. Some lead concentrations in straw mushrooms exceeded the EU standard (>3 mg kg⁻¹ dw).

Removal of lead (II) from aqueous solutions using rice straw.

Science.gov (United States)

Amer, Hayam; El-Gendy, Ahmed; El-Haggar, Salah

2017-09-01

Lead (Pb 2+ ) is a heavy metal which is utilized in several industries and can have severe impact on the environment and human health. Research work has been carried out lately on the feasibility of using various low cost materials in the removal of heavy metals from wastewater. In this study, the feasibility of utilizing raw rice straw for removal of Pb 2+ from water through biosorption was investigated using batch equilibrium experiments. The effect of several operating parameters on the removal of Pb 2+ using rice straw was studied, revealing the optimum parameters at an initial Pb 2+ concentration of 40 mg/l were: 30 min contact time at a pH of 5.5, particle size 75-150 μm and a dose of 4 g/l. A maximum removal of 94% was achieved under optimum conditions. Langmuir and Freundlich isotherm models were used for the evaluation of the equilibrium experimental data. The maximum adsorption capacity of rice straw calculated using the Langmuir isotherm was 42.55 mg/g.

Urea-ensiled rice straw as a feed for cattle in Thailand

African Journals Online (AJOL)

straw. Rice straw contains about 3% crude protein (air- dry basis), 35% crude fiber and 1900kcal DE/kg of straw. Because of its low energy and protein content, ... corn, 9,4 kg soybean meal, 10 kg coconut meal, 2 kg mineral, 2 kg bone meal and 1 kg salt. Table 3 Performance of crossbred heifers fed with different roughages.

Development of a new lactic acid bacterial inoculant for fresh rice straw silage

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Jong Geun Kim

2017-07-01

Full Text Available Objective Effects of newly isolated Lactobacillus plantarum on the fermentation and chemical composition of fresh rice straw silage was evaluated in this study. Methods Lactic acid bacteria (LAB from good crop silage were screened by growing them in MRS broth and a minimal medium with low carbohydrate content. Selected LAB (LAB 1821 were Gram-positive, rods, catalase negative, and were identified to be Lactobacillus plantarum based on their biochemical characteristics and a 16S rRNA analysis. Fresh rice straw was ensiled with two isolated LAB (1821 and 1841, two commercial inoculants (HM/F and P1132 and no additive as a control. Results After 2 months of storage at ambient temperature, rice straw silages treated with additives were well-preserved, the pH values and butyric and acetic acid contents were lower, and the lactic acid content and lactic/acetic acid ratio were higher than those in the control (p0.05 effect on acid detergent fiber or neutral detergent fiber contents. Crude protein (CP content and in vitro DM digestibility (IVDMD increased after inoculation of LAB 1821 (p<0.05. Conclusion LAB 1821 increased the CP, IVDMD, lactic acid content and ratio of lactic acid to acetic acid in rice straw silage and decreased the pH, acetic acid, NH3-N, and butyric acid contents. Therefore, adding LAB 1821 improved the fermentation quality and feed value of rice straw silage.

Long-term rice cultivation stabilizes soil organic carbon and promotes soil microbial activity in a salt marsh derived soil chronosequence

Science.gov (United States)

Wang, Ping; Liu, Yalong; Li, Lianqing; Cheng, Kun; Zheng, Jufeng; Zhang, Xuhui; Zheng, Jinwei; Joseph, Stephen; Pan, Genxing

2015-01-01

Soil organic carbon (SOC) sequestration with enhanced stable carbon storage has been widely accepted as a very important ecosystem property. Yet, the link between carbon stability and bio-activity for ecosystem functioning with OC accumulation in field soils has not been characterized. We assessed the changes in microbial activity versus carbon stability along a paddy soil chronosequence shifting from salt marsh in East China. We used mean weight diameter, normalized enzyme activity (NEA) and carbon gain from straw amendment for addressing soil aggregation, microbial biochemical activity and potential C sequestration, respectively. In addition, a response ratio was employed to infer the changes in all analyzed parameters with prolonged rice cultivation. While stable carbon pools varied with total SOC accumulation, soil respiration and both bacterial and fungal diversity were relatively constant in the rice soils. Bacterial abundance and NEA were positively but highly correlated to total SOC accumulation, indicating an enhanced bio-activity with carbon stabilization. This could be linked to an enhancement of particulate organic carbon pool due to physical protection with enhanced soil aggregation in the rice soils under long-term rice cultivation. However, the mechanism underpinning these changes should be explored in future studies in rice soils where dynamic redox conditions exist. PMID:26503629

Improving the quality of rice straw by urea and calcium hydroxide on rumen ecology, microbial protein synthesis in beef cattle.

Science.gov (United States)

Polyorach, S; Wanapat, M

2015-06-01

Four rumen-fistulated beef cattle were randomly assigned to four treatments according to a 4 × 4 Latin square design to study the influence of urea and calcium hydroxide [Ca(OH)2 ] treatment of rice straw to improve the nutritive value of rice straw. Four dietary treatments were as follows: untreated rice straw, 50 g/kg urea-treated rice straw, 20 g/kg urea + 20 g/kg calcium hydroxide-treated rice straw and 30 g/kg urea + 20 g/kg calcium hydroxide-treated rice straw. All animals were kept in individual pens and fed with concentrate at 0.5 g/kg of BW (DM), rice straw was fed ad libitum. The experiment was conducted for four periods, and each period lasted for 21 days. During the first 14 days, DM feed intake measurements were made while during the last 7 days, all cattle were moved to metabolism crates for total faeces and urine collections. The results revealed that 20 g/kg urea + 20 g/kg calcium hydroxide-treated rice straw improved the nutritive value of rice straw, in terms of dry matter intake, digestibility, ruminal volatile fatty acids, population of bacteria and fungi, nitrogen retention and microbial protein synthesis. Based on this study, it could be concluded that using urea plus calcium hydroxide was one alternative method to improve the nutritive value of rice straw, rumen ecology and fermentation and thus a reduction of treatment cost. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

Rice and wheat yield improvement by the application of boron in salt affected soils

International Nuclear Information System (INIS)

Mehdi, S.M.; Sarfraz, M.; Hassan, N.M.; Hassan, W.

2007-01-01

In recent past studies on wheat, rice and fruit plant showed that fairly large percentage of soils and crops are deficient in boron. Several times a question rose to study the boron responses in a cropping system to see the residual effect of boron. With the objective in mind, a field experiment was conducted at two sites in saline sodic soils to see the rice and wheat crops response to boron. Boron was applied to rice at the rate of 0.25, 0.50, 1.0, 1.5, and 2.0 Kg ha/sub -1/ as sodium tetra borate. The results showed that both paddy and straw yields increased with the increasing rates of boron and highest yield was obtained from 2 Kg ha/sub -l/. After harvesting of rice crop wheat was sown in the same layout. The treatments were divided into two equal portions. Boron was applied to one portion at the same rates as to rice while remaining half remained as such to study the residual effect of B on wheat. The results showed that grain anti straw yields increased with increasing rates of boron. In case of untreated plots to see the residual effect grain and straw yield increased with increasing rates of boron applied to rice. It was concluded that B applied to rice did show residual effect to the following wheat crop. Therefore, there is no need to apply B to following crop when B is applied to the previous crop. (author)

Rice-straw mulch reduces the green peach aphid, Myzus persicae (Hemiptera: Aphididae) populations on kale, Brassica oleracea var. acephala (Brassicaceae) plants.

Science.gov (United States)

Silva-Filho, Reinildes; Santos, Ricardo Henrique Silva; Tavares, Wagner de Souza; Leite, Germano Leão Demolin; Wilcken, Carlos Frederico; Serrão, José Eduardo; Zanuncio, José Cola

2014-01-01

Organic mulches, like peel and rice-straw, besides other materials affect the UV and temperature, which cause a reduction in the aphid arrival. The aim was to evaluate the effect of covering the soil with straw on the populations of the green peach aphid, Myzus persicae on the kale, Brassica oleracea var. acephala plants. The first experiment evaluated the direct effect of the rice-straw mulch and the second its indirect effect on aphid immigration, testing the plant characteristics that could lead to the landing preference of this insect. The third experiment evaluated the direct effect of the mulch on the aphid population. In the second and third experiments, four plants, each in a 14 L polyethylene pot with holes at the bottom, were used in areas with and without soil mulching. These pots were changed between areas, after seven days, to evaluate the effects of this change on the arrival of the winged aphids to the plants. Each plant was covered with anti-aphid gauze and inoculated with one winged M. persicae. Winged and apterous adults of this insect were counted per plant after 15 days. The temperature increased in the mulched plots to a maximum of 21-36°C and to 18-32°C in the plots with or without soil covering, respectively. Plant growth reduced the numbers of the winged aphids landing before and after they were moved to the bare soil plots. The nutrient content was similar in plants in both the mulched and no mulched plots. The population growth of M. persicae was higher in the control than in the mulched plots. This was partially due to temperatures close to 30°C in these plots and changes in the plant physiology. The soil mulching with rice-straw decreased the M. persicae landing, increased the plot temperatures and improved the vegetative growth of the kale plants.

Rice-straw mulch reduces the green peach aphid, Myzus persicae (Hemiptera: Aphididae populations on kale, Brassica oleracea var. acephala (Brassicaceae plants.

Directory of Open Access Journals (Sweden)

Reinildes Silva-Filho

Full Text Available Organic mulches, like peel and rice-straw, besides other materials affect the UV and temperature, which cause a reduction in the aphid arrival. The aim was to evaluate the effect of covering the soil with straw on the populations of the green peach aphid, Myzus persicae on the kale, Brassica oleracea var. acephala plants. The first experiment evaluated the direct effect of the rice-straw mulch and the second its indirect effect on aphid immigration, testing the plant characteristics that could lead to the landing preference of this insect. The third experiment evaluated the direct effect of the mulch on the aphid population. In the second and third experiments, four plants, each in a 14 L polyethylene pot with holes at the bottom, were used in areas with and without soil mulching. These pots were changed between areas, after seven days, to evaluate the effects of this change on the arrival of the winged aphids to the plants. Each plant was covered with anti-aphid gauze and inoculated with one winged M. persicae. Winged and apterous adults of this insect were counted per plant after 15 days. The temperature increased in the mulched plots to a maximum of 21-36°C and to 18-32°C in the plots with or without soil covering, respectively. Plant growth reduced the numbers of the winged aphids landing before and after they were moved to the bare soil plots. The nutrient content was similar in plants in both the mulched and no mulched plots. The population growth of M. persicae was higher in the control than in the mulched plots. This was partially due to temperatures close to 30°C in these plots and changes in the plant physiology. The soil mulching with rice-straw decreased the M. persicae landing, increased the plot temperatures and improved the vegetative growth of the kale plants.

Free radical induced grafting of acrylonitrile on pre-treated rice straw for enhancing its durability and flame retardancy

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Aparna Mukherjee

2017-01-01

Full Text Available The present investigation highlights the feasibility of a polymer grafting process to enhance the durability and flame retardancy of rice straw towards application as a low cost roofing material. The success of this grafting methodology was perceived to depend upon a bi-step pre-treatment process encompassing delignification and inorganic salts dispersion. Subsequently free radical polymer grafting of acrylonitrile onto rice straw was implemented by immersion mechanism initiated by oxalic acid-potassium permanganate initiator. The percentage of grafting, limiting oxygen index (LOI, biodegradability of the grafted rice straw and grafting yield percentage was estimated to be 57%, 27%, 0.02% and 136.67%, respectively. The weight loss of polymer grafted rice straw implied its less biodegradability over raw straw. Thus, the process of grafting contrived in the present analysis can be a promising and reliable technique for the efficient utilization of rice straw as an inexpensive roofing element through the augmentation of its durability and flame retardancy.

Pre-feasibility study for an electric power plant based on rice straw. [Mali

Energy Technology Data Exchange (ETDEWEB)

Fock, F. [Ea Energy Analysis, Copenhagen (Denmark); Nygaard, I. [Technical Univ. of Denmark. DTU Management Engineering, UNEP Risoe Centre on Energy, Climate and Sustainable Development, Roskilde (Denmark); Maiga, A.; Kone, B.; Kamissoko, F.; Coulibaly, N.; Ouattara, O.

2012-11-15

The main objective is to make a first evaluation regarding if it's technically possible, economically viable, sustainable and recommendable to build a rice straw/hulls fired power plant in Niono in Mali. Based on the available resource of rice straw and the possibilities for connecting to the grid it has been chosen to analyse a 5 MW power plant in the project. For technical reasons the rice straw should be the main fuel, but rice hulls can be used for co-firing. Up to around 20% of the fuel in the plant can be rice hulls instead of rice straw. A number of different biomass power production technologies have been evaluated in the project. This includes: 1) Grate fired boiler. 2) Bubbling fluidised bed. 3) Circulating fluidised bed. 4) Dust fired boiler. 5) Gasification. 6) Stirling engine. 7) Organic Rankine Cycle. Grate firing is the most relevant technology in this case, due to the fuel, the size of the power plant, the demand for electricity only and not heat, the demand for a robust and well proven technology. For a grate fired plant a calculation of the thermodynamic process of the power plant has been carried out in order to determine the electrical efficiency of the plant. The case consists of a 5 MW grate fired power plant with steam turbines and air cooled condenser resulting in an efficiency of 24.6% at full load (20% as yearly average). Investment costs and costs for O and M have been assumed based on experience from Danish power plants but adjusted for local conditions in Mali. The costs for collecting and transporting the rice straw and for the ash disposal have been specifically estimated in this project. The average cost of capital has been estimated based on assumptions on equity, international loans and local loans/bank finance. Based on the investment, the cost of O and M, fuel, ash disposal and the financial assumptions, a cash flow analysis is made in order to calculate the power price resulting in a Net Present Value (NPV) of the

Influence of rice straw burning on the levels of polycyclic aromatic hydrocarbons in agricultural county of Taiwan.

Science.gov (United States)

Lai, Chia-Hsiang; Chen, Kang-Shin; Wang, Hsin-Kai

2009-01-01

Atmospheric particulate and polycyclic aromatic hydrocarbons (PAHs) size distribution were measured at Jhu-Shan (a rural site) and Sin-Gang (a town site) in central Taiwan during the rice straw burning and non-burning periods. The concentrations of total PAHs accounting for a roughly 58% (34%) increment in the concentrations of total PAHs due to rice-straw burning. Combustion-related PAHs during burning periods were 1.54-2.57 times higher than those during non-burning periods. The mass median diameter (MMD) of 0.88-1.21 microm in the particulate phase suggested that rice-straw burning generated the increase in coarse particle number. Chemical mass balance (CMB) receptor model analyses showed that the primary pollution sources at the two sites were similar. However, rice-straw burning emission was specifically identified as a significant source of PAH during burning periods at the two sites. Open burning of rice straws was estimated to contribute approximately 6.3%-24.6% to total atmospheric PAHs at the two sites.

Biochar amendment immobilizes lead in rice paddy soils and reduces its phytoavailability

Science.gov (United States)

Li, Honghong; Liu, Yuting; Chen, Yanhui; Wang, Shanli; Wang, Mingkuang; Xie, Tuanhui; Wang, Guo

2016-08-01

This study aimed to determine effects of rice straw biochar on Pb sequestration in a soil-rice system. Pot experiments were conducted with rice plants in Pb-contaminated paddy soils that had been amended with 0, 2.5, and 5% (w/w) biochar. Compared to the control treatment, amendment with 5% biochar resulted in 54 and 94% decreases in the acid soluble and CaCl2-extractable Pb, respectively, in soils containing rice plants at the maturity stage. The amount of Fe-plaque on root surfaces and the Pb concentrations of the Fe-plaque were also reduced in biochar amended soils. Furthermore, lead species in rice roots were determined using Pb L3-edge X-ray absorption near edge structure (XANES), and although Pb-ferrihydrite complexes dominated Pb inventories, increasing amounts of organic complexes like Pb-pectins and Pb-cysteine were found in roots from the 5% biochar treatments. Such organic complexes might impede Pb translocation from root to shoot and subsequently reduce Pb accumulation in rice with biochar amendment.

Rice straw pulp obtained by using various methods.

Science.gov (United States)

Rodríguez, Alejandro; Moral, Ana; Serrano, Luis; Labidi, Jalel; Jiménez, Luis

2008-05-01

Rice straw was used as an alternative raw material to obtain cellulosics pulps. Pulping was done by using classics reagents as soda (with anthraquinone and parabenzoquinone as aditives), potassium hydroxide and Kraft process. The holocellulose, alpha-cellulose and lignin contents of rice straw (viz. 60.7, 41.2 and 21.9 wt%, respectively) are similar to those of some woody raw materials such as pine and eucalyptus, and various non-wood materials including olive tree prunings, wheat straw and sunflower stalks. Pulping tests were conducted by using soda, soda and anthraquinone at 1 wt%, soda and parabenzoquinone at 1 wt%, potassium hydroxide and sodium sulphate (Kraft process) under two different sets of operating conditions, namely: (a) a 10 wt% reagent concentration, 170 degrees C and 60 min; and (b) 15 wt% reagent, 180 degrees C and 90 min. The solid/liquid ratio was 6 in both cases. Paper sheets made from pulp extracted by cooking with soda (15 wt%) and AQ (1 wt%) at 180 degrees C and 90 min pulp exhibit the best drainage index, breaking length, stretch and burst index (viz. 23 degrees SR, 3494 m, 3.34% and 2.51 kN/g, respectively).

Factors Causing Farmers Not to Ferment Rice Straw as Cattle Feed

Science.gov (United States)

Sirajuddin, S. N.; Saleh, I. M.; Syawal, S.; Syamsinar

2018-02-01

This study aimed was to identify the factor of breeders have not done fermentation of rice straw as cattle feed. This research was conducted on August-September 2017 in Patampanua village, Marioriawa sub-district, Soppeng district. This research is descriptive quantitative with Delbeq method. Data collection is qualitative and quantitative. Data sources are primary and secondary data. Data analysis used is frequency distribution. The results showed that farmers have not done the fermentation of rice straw as animal feed that is the motivation of farmers, intensity counseling and lack of knowledge of farmers

The effect of pretreatment using sodium hydroxide and acetic acid to biogas production from rice straw waste

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Budiyono

2017-01-01

Full Text Available Rice straw is agricultural waste containing high potency to be treated to biogas. However, the usage of rice straw is still limited due to high lignin content that will cause low biodegradability. The aim of this research was to study the effect of pretreatment using NaOH and acetic acid to biogas production from rice straw. NaOH was varied from 2%w, 4%w, and 6%w; and acetic acid was varied from 0,075 M, 0,15 M dan 0,75 M. The rice straw was cut into 1 cm size and submerged for 30 minutes in NaOH and acetic acid solution. The rice straw then filtered and neutralized before sending to anaerobic digestion process using rumen fluid bacteria. Biogas produced was measured using water displacement method. The result showed that the optimum concentration of NaOH solution was 4%w that resulted in biogas volume of 21,1 ml/gTS. Meanwhile, the optimum concentration of acetic acid pretreatment was 0,075 M that produced biogas volume of 14,5 ml/gTS. These results suggest that pretreatment using NaOH solution is more effective for decreasing the lignin content from rice straw.

Use of rice straw ash as substitute of feldspar in triaxial porcelain

OpenAIRE

Guzmán, Álvaro; Delvasto, Silvio; Sánchez, Enrique; Amigó Borrás, Vicente

2013-01-01

[EN] The substitution of raw materials for processing high energy consumption materials by agricultural and agro-industrial wastes causes a positive impacts on the environment preservation. One of these residues is rice straw, which according to FAO estimation, its annual production is about 600 million tons. In this research was studied the use of rice straw ash (RSA) as substitute of the use of feldspar in the whiteware production. Clay-feldspar-quartz porcelains are referred to...

Prospects of rice straw as a raw material for paper making.

Science.gov (United States)

Kaur, Daljeet; Bhardwaj, Nishi Kant; Lohchab, Rajesh Kumar

2017-02-01

Pulp and paper mills are indispensable for any nation as far as the growth of the nation is concerned. Due to fast growth in population, urbanization and industrialization, the demand and consumption of paper has increased tremendously. These put high load on our natural resources and force the industry to look for alternative raw material. Rice straw is a lignocellulosic material abundantly available in wood short countries like China, India, Bangladesh, etc. and can be used as raw material for this industry. Open burning of rice straw releases noxious green house gases to the air and poses serious threats to global air chemistry and human health. So, it is a dual benefit option (for farmers and industries) to use rice straw as a raw material in pulp and paper industry. Organosolv pulping using acids are the prominent choices of researchers to convert this residue into valuable pulp but in developed countries only. Developing world favours the soda and soda-AQ processes as these are economical. As a virtue of less lignin content in comparison to wood, rice straw requires less harsh conditions for cooking and can be easily pulped. Bleaching is a crucial step of paper making but also responsible for causing water pollution. Many studies revealed that during the process more than 500 chlorinated compounds are released that are highly toxic, bioaccumulative and carcinogenic in nature. Most of the industries over the globe switch on to the elemental chlorine free short sequence bleaching methods using chlorine dioxide, hypochlorite and hydrogen peroxide. This paper presented the effective need of ecofriendly, economically reliable pulping and bleaching sequences in case of rice straw to eliminate the problems of chlorinated compounds in wastewater of paper mills. Such approach of using waste as a raw material with its environmentally safe processing for making paper can prove to be valuable towards sustainable growth. Copyright © 2016 Elsevier Ltd. All rights reserved.

Selected properties of particleboard panels manufactured from rice straws of different geometries

Science.gov (United States)

Xianjun Li; Zhiyong Cai; Jerrold E. Winandy; Altaf H. Basta

2010-01-01

The objective is to evaluate the primary mechanical and physical properties of particleboard made from hammer-milled rice straw particles of six different categories and two types of resins. The results show the performance of straw particleboards is highly dependent upon the straw particle size controlled by the opening size of the perforated plate inside the hammer-...

Genetic control of a transition from black to straw-white seed hull in rice domestication.

Science.gov (United States)

Zhu, Bo-Feng; Si, Lizhen; Wang, Zixuan; Zhou, Yan; Zhu, Jinjie; Shangguan, Yingying; Lu, Danfeng; Fan, Danlin; Li, Canyang; Lin, Hongxuan; Qian, Qian; Sang, Tao; Zhou, Bo; Minobe, Yuzo; Han, Bin

2011-03-01

The genetic mechanism involved in a transition from the black-colored seed hull of the ancestral wild rice (Oryza rufipogon and Oryza nivara) to the straw-white seed hull of cultivated rice (Oryza sativa) during grain ripening remains unknown. We report that the black hull of O. rufipogon was controlled by the Black hull4 (Bh4) gene, which was fine-mapped to an 8.8-kb region on rice chromosome 4 using a cross between O. rufipogon W1943 (black hull) and O. sativa indica cv Guangluai 4 (straw-white hull). Bh4 encodes an amino acid transporter. A 22-bp deletion within exon 3 of the bh4 variant disrupted the Bh4 function, leading to the straw-white hull in cultivated rice. Transgenic study indicated that Bh4 could restore the black pigment on hulls in cv Guangluai 4 and Kasalath. Bh4 sequence alignment of all taxa with the outgroup Oryza barthii showed that the wild rice maintained comparable levels of nucleotide diversity that were about 70 times higher than those in the cultivated rice. The results from the maximum likelihood Hudson-Kreitman-Aguade test suggested that the significant reduction in nucleotide diversity in rice cultivars could be caused by artificial selection. We propose that the straw-white hull was selected as an important visual phenotype of nonshattered grains during rice domestication.

Binding and detoxification of chlorpyrifos by lactic acid bacteria on rice straw silage fermentation.

Science.gov (United States)

Wang, Yan-Su; Wu, Tian-Hao; Yang, Yao; Zhu, Cen-Ling; Ding, Cheng-Long; Dai, Chuan-Chao

2016-01-01

This investigation examined the reduction of pesticide residues on straw inoculated with lactic acid bacteria (LAB) during ensiling. Lactobacillus casei WYS3 was isolated from rice straw that contained pesticide residues. Non-sterilized rice straw, which was inoculated with L. casei WYS3, showed increased removal of chlorpyrifos after ensiling, compared with rice straw that was not inoculated with L. casei WYS3 or sterilized rice straw. In pure culture, these strains can bind chlorpyrifos as indicated by high-performance liquid chromatography analysis. Viable L. casei WYS3 was shown to bind 33.3-42% of exogenously added chlorpyrifos. These results are similar to those of acid-treated cells but less than those of heat-treated cells, which were found to bind 32.0% and 77.2% of the added chlorpyrifos respectively. Furthermore, gas chromatography-mass spectrometry analysis determined that L. casei WYS3 detoxified chlorpyrifos via P-O-C cleavage. Real-time polymerized chain reaction analysis determined that organophosphorus hydrolase gene expression tripled after the addition of chlorpyrifos to LAB cultures, compared with the control group (without chlorpyrifos). This paper highlights the potential use of LAB starter cultures for the detoxification and removal of chlorpyrifos residues in the environment.

Antifungal activity of rice straw extract on some phytopathogenic fungi

African Journals Online (AJOL)

The antifungal activity of allelochemicals extracted from rice straw on the radial growth rate and the activity of some hydrolyzing enzymes of Aspergillus flavus, Alternaria alternata and Botrytis cinerea were studied in vitro. Five different concentrations (2, 4, 6, 8 and 10%, w/v) of water, methanol and acetone extracts of rice ...

Phytoremediation of arsenic contaminated paddy soils with Pteris vittata markedly reduces arsenic uptake by rice.

Science.gov (United States)

Ye, Wen-Ling; Khan, M Asaduzzaman; McGrath, Steve P; Zhao, Fang-Jie

2011-12-01

Arsenic (As) accumulation in food crops such as rice is of major concern. To investigate whether phytoremediation can reduce As uptake by rice, the As hyperaccumulator Pteris vittata was grown in five contaminated paddy soils in a pot experiment. Over a 9-month period P. vittata removed 3.5-11.4% of the total soil As, and decreased phosphate-extractable As and soil pore water As by 11-38% and 18-77%, respectively. Rice grown following P. vittata had significantly lower As concentrations in straw and grain, being 17-82% and 22-58% of those in the control, respectively. Phytoremediation also resulted in significant changes in As speciation in rice grain by greatly decreasing the concentration of dimethylarsinic acid (DMA). In two soils the concentration of inorganic As in rice grain was decreased by 50-58%. The results demonstrate an effective stripping of bioavailable As from contaminated paddy soils thus reducing As uptake by rice. Copyright © 2011 Elsevier Ltd. All rights reserved.

Influence of rice straw polyphenols on cellulase production by Trichoderma reesei.

Science.gov (United States)

Zheng, Wei; Zheng, Qin; Xue, Yiyun; Hu, Jiajun; Gao, Min-Tian

2017-06-01

In this study, we found that during cellulase production by Trichoderma reesei large amounts of polyphenols were released from rice straw when the latter was used as the carbon source. We identified and quantified the phenolic compounds in rice straw and investigated the effects of the phenolic compounds on cellulase production by T. reesei. The phenolic compounds of rice straw mainly consisted of phenolic acids and tannins. Coumaric acid (CA) and ferulic acid (FA) were the predominant phenolic acids, which inhibited cellulase production by T. reesei. When the concentrations of CA and FA in the broth increased to 0.06 g/L, cellulase activity decreased by 23% compared with that in the control culture. Even though the rice straw had a lower tannin than phenolic acid content, the tannins had a greater inhibitory effect than the phenolic acids on cellulase production by T. reesei. Tannin concentrations greater than 0.3 g/L completely inhibited cellulase production. Thus, phenolic compounds, especially tannins are the major inhibitors of cellulase production by T. reesei. Therefore, we studied the effects of pretreatments on the release of phenolic compounds. Ball milling played an important role in the release of FA and CA, and hot water extraction was highly efficient in removing tannins. By combining ball milling with extraction by water, the 2-fold higher cellulase activity than in the control culture was obtained. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

[Impacts of rice straw biochar on organic carbon and CO2 release in arable soil].

Science.gov (United States)

Ke, Yue-Jin; Hu, Xue-Yu; Yi, Qing; Yu, Zhong

2014-01-01

In order to investigate the stability of biochar and the effect of biochar when added into soil on soil organic carbon, a 130-day incubation experiment was conducted with rice straw biochar produced at 500 degrees C and 700 degrees C (RBC500 and RBC700) and with addition rates of 0% (control), 3%, 6% and 100% (pure biochar), to detect the change of total organic carbon (TOC), easily oxidized carbon (EOC) and status of CO2 release, following addition of biochar in arable soil. Results showed that: the content of both TOC and EOC in soil increased with biochar addition rates comparing with the control. RBC500 had greater contributions to both TOC and EOC increasing amounts than those of RBC700 under the same biochar addition rate. TOC contents of all treatments decreased during the initial 30 days with the largest decreasing amplitude of 15.8%, and tended to be stable in late incubation stages. Same to that of TOC, EOC contents of all treatments also tended to remain stable after 30 days, but in the 30 days of early incubation, EOC in the soil decreased by 72.4% and 81.7% respectively when the added amount of RBC500 was 3% and 6% , while it was reduced by 61.3% and 69.8% respectively when the added amount of RBC700 was 3% and 6%. EOC contents of soil added with biochar produced at the same temperature were similar in the end of incubation. The reduction of soil EOC content in early incubation may be related to mineralization caused by labile fractions of biochar. During the 130-day incubation, the accumulated CO2 releases showed an order of soil and biochar mixtures soil could reduce CO2 release, the largest reduction amplitude is 41.05%. In a long time scale, biochar as a soil amendment is favorable to the deduction of greenhouse gas release and soil carbon immobilization. Biochar could be used as a soil carbon sequestration carrier.

Effects of Residue Management on Decomposition in Irrigated Rice Fields Are Not Related to Changes in the Decomposer Community.

Science.gov (United States)

Schmidt, Anja; John, Katharina; Arida, Gertrudo; Auge, Harald; Brandl, Roland; Horgan, Finbarr G; Hotes, Stefan; Marquez, Leonardo; Radermacher, Nico; Settele, Josef; Wolters, Volkmar; Schädler, Martin

2015-01-01

Decomposers provide an essential ecosystem service that contributes to sustainable production in rice ecosystems by driving the release of nutrients from organic crop residues. During a single rice crop cycle we examined the effects of four different crop residue management practices (rice straw or ash of burned straw scattered on the soil surface or incorporated into the soil) on rice straw decomposition and on the abundance of aquatic and soil-dwelling invertebrates. Mass loss of rice straw in litterbags of two different mesh sizes that either prevented or allowed access of meso- and macro-invertebrates was used as a proxy for decomposition rates. Invertebrates significantly increased total loss of litter mass by up to 30%. Initially, the contribution of invertebrates to decomposition was significantly smaller in plots with rice straw scattered on the soil surface; however, this effect disappeared later in the season. We found no significant responses in microbial decomposition rates to management practices. The abundance of aquatic fauna was higher in fields with rice straw amendment, whereas the abundance of soil fauna fluctuated considerably. There was a clear separation between the overall invertebrate community structure in response to the ash and straw treatments. However, we found no correlation between litter mass loss and abundances of various lineages of invertebrates. Our results indicate that invertebrates can contribute to soil fertility in irrigated paddy fields by decomposing rice straw, and that their abundance as well as efficiency in decomposition may be promoted by crop residue management practices.

Enzymatic hydrolysis of alkali-pretreated rice straw by Trichoderma reesei ZM4-F3

Energy Technology Data Exchange (ETDEWEB)

Zhang, QiuZhuo [Department of Environmental Science and Engineering, Harbin Institute of Technology, Harbin 150090 (China); Cai, WeiMin [Department of Environmental Science and Engineering, Harbin Institute of Technology, Harbin 150090 (China); School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240 (China)

2008-12-15

To minimize the cost of cellulase production, both pretreatment of the rice straw and on-site enzyme production were realized. Rice straw was first pretreated by 2% NaOH, which could increase cellulose by 54.83%, and decreased hemicellulose by 61.07% and lignin by 36.24%, respectively. Detected by SEM, significant morphological changes were observed in the tissue. Through orthogonal experiments, temperature 35 C, initial pH value 4.5 and the rotation speed of shaking bed 180 rpm were determined to be the optimal conditions for hydrolysis of rice straw by Trichoderma reesei ZM4-F3. After hydrolysis for 96 h, the production of FPA and reducing sugars could achieve 2.231 g l{sup -1} and 12.92 U ml{sup -1}, respectively. Moreover, T. reesei ZM4-F3 can decompose 68.21% of pretreated rice straw after 120 h of hydrolysis. By GC analysis, it showed that glucose is the main component of the enzymatic hydrolysates, which made GC seem to be more effective than the DNS method for analysis of the enzymatic hydrolysates as it can detect the concentration of each kind of monosaccharide more accurately. (author)

[Selenium uptake and transport of rice under different Se-enriched natural soils].

Science.gov (United States)

Jiang, Chao-qiang; Shen, Jia; Zu, Chao-long

2015-03-01

In this study, a pot experiment was conducted with "Wandao 205" as test materials to investigate Se uptake and translocation in rice under different Se concentrations (0.5, 1.0, and 1.5 mg . kg-1). Results showed that there was no significant change in rice yield when Se concentration in soil was lower than 1.5 mg . kg-1. Significant linear correlations existed between Se concentration in soil and different rice plant tissues. Se concentration in rice plant followed the order of root > straw > grain. Se concentration in different rice grain fractions followed the order of bran > polished rice > hull. The root absorption index of Se was more than 1.86, suggest that the rice could absorpt Se from soil effectively. However, the transport and accumulation of Se in seeds from Se-enriched soil was relatively constant. The Se transport index in seeds was between 0.53 and 0.59. Soil Se concentration within the range of 0.5 to 1.0 mg . kg-1 could produce Se-enriched rice, which might be enough for human requirement of 60-80 µg . d-1 Se. However, polished rice at high-Se treatment (1.5 mg . kg-1) exceeded the maximum standard limit of Se (0.3 mg . kg-1) for cereals in China. These results suggested that we could produce Se-enriched rice under soil Se concentration in the range of 0.5 to 1.0 mg . kg-1 without spraying Se fertilizer, thus reducing the cost and avoiding soil and water pollution caused by exogenous Se.

What factors influence choice of waste management practice? Evidence from rice straw management in the Philippines.

Science.gov (United States)

Launio, Cheryll C; Asis, Constancio A; Manalili, Rowena G; Javier, Evelyn F; Belizario, Annabelle F

2014-02-01

This study applied a multinomial logit model to understand why farmers choose to burn, incorporate or remove rice straw in the field. Four hundred randomly selected farmers were interviewed in four major rice-producing provinces covering the 2009 wet and 2010 dry seasons. Results of the model with burning as the baseline category indicate farm type, location dummies, number of household members with older than 13 years, cow ownership and distance from farm to house as significant variables influencing farmers' choice of straw incorporation or removal over burning. Significant perception variables are the negative impacts of open-field burning, awareness of environmental regulations and attitude towards incentives. Other factors significantly influencing the decision to incorporate over-burn are training attendance and perceptions of effects of straw incorporation. Income from non-rice farming, total area cultivated, tenure status, presence of burning and solid waste management provincial ordinances are significant factors affecting choice to remove over burn. Continually providing farmers' training in rice production, increasing demand for rice straw for other uses, and increasing awareness of environmental laws and regulations are policy directions recommended.

Cadmium availability in rice paddy fields from a mining area: The effects of soil properties highlighting iron fractions and pH value.

Science.gov (United States)

Yu, Huan-Yun; Liu, Chuanping; Zhu, Jishu; Li, Fangbai; Deng, Dong-Mei; Wang, Qi; Liu, Chengshuai

2016-02-01

Cadmium (Cd) availability can be significantly affected by soil properties. The effect of pH value on Cd availability has been confirmed. Paddy soils in South China generally contain high contents of iron (Fe). Thus, it is hypothesized that Fe fractions, in addition to pH value, may play an important role in the Cd bioavailability in paddy soil and this requires further investigation. In this study, 73 paired soil and rice plant samples were collected from paddy fields those were contaminated by acid mine drainage containing Cd. The contents of Fe in the amorphous and DCB-extractable Fe oxides were significantly and negatively correlated with the Cd content in rice grain or straw (excluding DCB-extractable Fe vs Cd in straw). In addition, the concentration of HCl-extractable Fe(II) derived from Fe(III) reduction was positively correlated with the Cd content in rice grain or straw. These results suggest that soil Fe redox could affect the availability of Cd in rice plant. Contribution assessment of soil properties to Cd accumulation in rice grain based on random forest (RF) and stochastic gradient boosting (SGB) showed that pH value should be the most important factor and the content of Fe in the amorphous Fe oxides should be the second most important factor in affecting Cd content in rice grain. Overall, compared with the studies from temperate regions, such as Europe and northern China, Fe oxide exhibited its unique role in the bioavailability of Cd in the reddish paddy soil from our study area. The exploration of practical remediation strategies for Cd from the perspective of Fe oxide may be promising. Copyright © 2015 Elsevier Ltd. All rights reserved.

Oxalic acid pretreatment of rice straw particles and loblolly pine chips : release of hemicellulosic carbohydrates

Science.gov (United States)

Xianjun Li; Zhiyong Cai; Eric Horn; Jerrold E. Winandy

2011-01-01

This study was conducted to evaluate the effect of oxalic acid (OA) pretreatment on carbohydrates released from rice straw particles and wood chips. The results showed that OA treatment accelerated carbohydrates extraction from rice straw particles and wood chips. OA pretreatment dramatically increased the amount of carbohydrates extracted, up to 24 times for wood...

Soil Respiration Controls Ionic Nutrient Concentration In Percolating Water In Rice Fields

Science.gov (United States)

Kimura, M.

2004-12-01

Soil water in the plow layer in rice fields contains various kinds of cations and anions, and they are lost from the plow layer by water percolation. Some portions of CO2 produced by respirations of rice roots and soil microorganisms are also leached by water percolation to the subsoil layer as HCO3-. As the electrical neutrality of inorganic substances in percolating water is maintained when they are assumed to be in the form of simple cations and anions, soil respiration accelerates the leaching of ionic nutrients from the plow layer by water percolation. The proportion of inorganic carbon (Σ CO2) originated from photosynthates in the total Σ CO2 in soil solution in the plow layer was from 28 to 36 % in the rice straw amended soil and from 16 to 31 % in the soil without rice straw amendment in a soil pot experiment with rice plant after the maximum tillering stage. Most of Σ CO2 in percolating water from the plow layer accumulates in the subsoil layer. Periodical measurement of Σ CO2 in percolating water at 13 and 40 cm soil depths indicated that 10 % of total soil organic C in the plow layer was leached down from the plow layer (13 cm), and that about 90 % of it was retained in the subsoil layer to the depth of 40 cm. Water soluble organic materials are also leached from the plow layer by water percolation, and the leaching is accelerated by soil reduction. Soil reduction decreased the content of organic materials that were bound with ferric iron in soil (extractable by 0.1M Na4P2O7 + NaBH4) and increased the content of organic materials that were extractable by the neutral chelating solution (0.1M Na4P2O7). In addition, water percolation transformed the latter organic materials to those that were extractable by water and a neutral salt. Considerable portions of organic materials in percolating water are adsorbed in the subsoil layer, and then partially decomposed and polymerized to specific soil organic materials in the subsoil. Organic materials that were

Characterization of Cr(VI) removal from aqueous solutions by a surplus agricultural waste-Rice straw

International Nuclear Information System (INIS)

Gao Hui; Liu Yunguo; Zeng Guangming; Xu Weihua; Li Ting; Xia Wenbin

2008-01-01

The removal of Cr(VI) from aqueous solution by rice straw, a surplus agricultural byproduct was investigated. The optimal pH was 2.0 and Cr(VI) removal rate increased with decreased Cr(VI) concentration and with increased temperature. Decrease in straw particle size led to an increase in Cr(VI) removal. Equilibrium was achieved in about 48 h under standard conditions, and Cr(III), which appeared in the solution and remained stable thereafter, indicating that both reduction and adsorption played a part in the Cr(VI) removal. The increase of the solution pH suggested that protons were needed for the Cr(VI) removal. A relatively high level of NO 3 - notably restrained the reduction of Cr(VI) to Cr(III), while high level of SO 4 2- supported it. The promotion of the tartaric acid modified rice straw (TARS) and the slight inhibition of the esterified rice straw (ERS) on Cr(VI) removal indicated that carboxyl groups present on the biomass played an important role in chromium remediation even though were not fully responsible for it. Isotherm tests showed that equilibrium sorption data were better represented by Langmuir model and the sorption capacity of rice straw was found to be 3.15 mg/g

Fermentation Quality and Additives: A Case of Rice Straw Silage

Directory of Open Access Journals (Sweden)

Yusuff Oladosu

2016-01-01

Full Text Available Rice cultivation generates large amount of crop residues of which only 20% are utilized for industrial and domestic purposes. In most developing countries especially southeast Asia, rice straw is used as part of feeding ingredients for the ruminants. However, due to its low protein content and high level of lignin and silica, there is limitation to its digestibility and nutritional value. To utilize this crop residue judiciously, there is a need for improvement of its nutritive value to promote its utilization through ensiling. Understanding the fundamental principle of ensiling is a prerequisite for successful silage product. Prominent factors influencing quality of silage product include water soluble carbohydrates, natural microbial population, and harvesting conditions of the forage. Additives are used to control the fermentation processes to enhance nutrient recovery and improve silage stability. This review emphasizes some practical aspects of silage processing and the use of additives for improvement of fermentation quality of rice straw.

Fermentation Quality and Additives: A Case of Rice Straw Silage.

Science.gov (United States)

Oladosu, Yusuff; Rafii, Mohd Y; Abdullah, Norhani; Magaji, Usman; Hussin, Ghazali; Ramli, Asfaliza; Miah, Gous

2016-01-01

Rice cultivation generates large amount of crop residues of which only 20% are utilized for industrial and domestic purposes. In most developing countries especially southeast Asia, rice straw is used as part of feeding ingredients for the ruminants. However, due to its low protein content and high level of lignin and silica, there is limitation to its digestibility and nutritional value. To utilize this crop residue judiciously, there is a need for improvement of its nutritive value to promote its utilization through ensiling. Understanding the fundamental principle of ensiling is a prerequisite for successful silage product. Prominent factors influencing quality of silage product include water soluble carbohydrates, natural microbial population, and harvesting conditions of the forage. Additives are used to control the fermentation processes to enhance nutrient recovery and improve silage stability. This review emphasizes some practical aspects of silage processing and the use of additives for improvement of fermentation quality of rice straw.

The use of steam explosion to increase the nutrition available from rice straw.

Science.gov (United States)

Li, Bin; Chen, Kunjie; Gao, Xiang; Zhao, Chao; Shao, Qianjun; Sun, Qian; Li, Hua

2015-01-01

In the present study, rice straw was pretreated using steam-explosion (ST) technique to improve the enzymatic hydrolysis of potential reducing sugars for feed utilization. The response surface methodology based on central composite design was used to optimize the effects of steam pressure, pressure retention time, and straw moisture content on the yield of reducing sugar. All the investigated variables had significant effects (P steam pressure, 1.54 MPa; pressure retention time, 140.5 Sec; and straw moisture content, 41.6%. The yield after thermal treatment under the same conditions was approximately 16%. Infrared (IR) radiation analysis showed a decrease in the cellulose IR crystallization index. ST noticeably increases reducing sugars in rice straw, and this technique may also be applicable to other cellulose/lignin sources of biomass. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

Dry co-digestion of sewage sludge and rice straw under mesophilic and thermophilic anaerobic conditions.

Science.gov (United States)

Chu, Xiangqian; Wu, Guangxue; Wang, Jiaquan; Hu, Zhen-Hu

2015-12-01

Dry anaerobic digestion of sewage sludge can recover biogas as energy; however, its low C/N ratio limits it as a single substrate in the anaerobic digestion. Rice straw is an abundant agricultural residue in China, which is rich in carbon and can be used as carbon source. In the present study, the performance of dry co-digestion of sewage sludge and rice straw was investigated under mesophilic (35 °C) and thermophilic (55 °C) conditions. The operational factors impacting dry co-digestion of sewage sludge and rice straw such as C/N ratio, moisture content, and initial pH were explored under mesophilic conditions. The results show that low C/N ratios resulted in a higher biogas production rate, but a lower specific biogas yield; low moisture content of 65 % resulted in the instability of the digestion system and a low specific biogas yield. Initial pH ranging 7.0-9.0 did not affect the performance of the anaerobic digestion. The C/N ratio of 26-29:1, moisture content of 70-80 %, and pH 7.0-9.0 resulted in good performance in the dry mesophilic co-digestion of sewage sludge and rice straw. As compared with mesophilic digestion, thermophilic co-digestion of sewage sludge and rice straw significantly enhanced the degradation efficiency of the substrates and the specific biogas yield (p sewage sludge under mesophilic and thermophilic conditions.

Yield and size of oyster mushroom grown on rice/wheat straw basal substrate supplemented with cotton seed hull.

Science.gov (United States)

Yang, Wenjie; Guo, Fengling; Wan, Zhengjie

2013-10-01

Oyster mushroom (Pleurotus ostreatus) was cultivated on rice straw basal substrate, wheat straw basal substrate, cotton seed hull basal substrate, and wheat straw or rice straw supplemented with different proportions (15%, 30%, and 45% in rice straw substrate, 20%, 30%, and 40% in wheat straw substrate) of cotton seed hull to find a cost effective substrate. The effect of autoclaved sterilized and non-sterilized substrate on growth and yield of oyster mushroom was also examined. Results indicated that for both sterilized substrate and non-sterilized substrate, oyster mushroom on rice straw and wheat basal substrate have faster mycelial growth rate, comparatively poor surface mycelial density, shorter total colonization period and days from bag opening to primordia formation, lower yield and biological efficiency, lower mushroom weight, longer stipe length and smaller cap diameter than that on cotton seed hull basal substrate. The addition of cotton seed hull to rice straw and wheat straw substrate slowed spawn running, primordial development and fruit body formation. However, increasing the amount of cotton seed hull can increase the uniformity and white of mycelium, yield and biological efficiency, and increase mushroom weight, enlarge cap diameter and shorten stipe length. Compared to the sterilized substrate, the non-sterilized substrate had comparatively higher mycelial growth rate, shorter total colonization period and days from bag opening to primordia formation. However, the non-sterilized substrate did not gave significantly higher mushroom yield and biological efficiency than the sterilized substrate, but some undesirable characteristics, i.e. smaller mushroom cap diameter and relatively long stipe length.

Effects of Residue Management on Decomposition in Irrigated Rice Fields Are Not Related to Changes in the Decomposer Community.

Directory of Open Access Journals (Sweden)

Anja Schmidt

Full Text Available Decomposers provide an essential ecosystem service that contributes to sustainable production in rice ecosystems by driving the release of nutrients from organic crop residues. During a single rice crop cycle we examined the effects of four different crop residue management practices (rice straw or ash of burned straw scattered on the soil surface or incorporated into the soil on rice straw decomposition and on the abundance of aquatic and soil-dwelling invertebrates. Mass loss of rice straw in litterbags of two different mesh sizes that either prevented or allowed access of meso- and macro-invertebrates was used as a proxy for decomposition rates. Invertebrates significantly increased total loss of litter mass by up to 30%. Initially, the contribution of invertebrates to decomposition was significantly smaller in plots with rice straw scattered on the soil surface; however, this effect disappeared later in the season. We found no significant responses in microbial decomposition rates to management practices. The abundance of aquatic fauna was higher in fields with rice straw amendment, whereas the abundance of soil fauna fluctuated considerably. There was a clear separation between the overall invertebrate community structure in response to the ash and straw treatments. However, we found no correlation between litter mass loss and abundances of various lineages of invertebrates. Our results indicate that invertebrates can contribute to soil fertility in irrigated paddy fields by decomposing rice straw, and that their abundance as well as efficiency in decomposition may be promoted by crop residue management practices.

Lignin derivatives from desilicated rice straw soda black liquor

Energy Technology Data Exchange (ETDEWEB)

El-Taraboulsi, M A; Nasser, M M

1979-01-01

Carboxymethyl lignin, cyanoethyl lignin, carboxyethyl lignin, and aminopropyl lignin were prepared from alkali lignin of rice straw black liquor (after disilication by storage for 1 wk to 1 yr) and used as sizes for paper, drilling fluid additives and flocculants.

Synthesis and Characterization of Rice Straw/Fe3O4 Nanocomposites by a Quick Precipitation Method

Directory of Open Access Journals (Sweden)

Katayoon Kalantari

2013-06-01

Full Text Available Small sized magnetite iron oxide nanoparticles (Fe3O4-NPs with were successfully synthesized on the surface of rice straw using the quick precipitation method in the absence of any heat treatment. Ferric chloride (FeCl3·6H2O, ferrous chloride (FeCl2·4H2O, sodium hydroxide (NaOH and urea (CH4N2O were used as Fe3O4-NPs precursors, reducing agent and stabilizer, respectively. The rice straw fibers were dispersed in deionized water, and then urea was added to the suspension, after that ferric and ferrous chloride were added to this mixture and stirred. After the absorption of iron ions on the surface layer of the fibers, the ions were reduced with NaOH by a quick precipitation method. The reaction was carried out under N2 gas. The mean diameter and standard deviation of metal oxide NPs synthesized in rice straw/Fe3O4 nanocomposites (NCs were 9.93 ± 2.42 nm. The prepared rice straw/Fe3O4-NCS were characterized using powder X-ray diffraction (PXRD, transmission electron microscopy (TEM, scanning electron microscopy (SEM, energy dispersive X-ray fluorescence (EDXF and Fourier transforms infrared spectroscopy (FT‒IR. The rice straw/Fe3O4-NCs prepared by this method have magnetic properties.

Possibility of using waste tire composites reinforced with rice straw as construction materials.

Science.gov (United States)

Yang, Han-Seung; Kim, Dae-Jun; Lee, Young-Kyu; Kim, Hyun-Joong; Jeon, Jin-Yong; Kang, Chun-Won

2004-10-01

Agricultural lignocellulosic fiber (rice straw)-waste tire particle composite boards were manufactured for use as insulation boards in construction, using the same method as that used in the wood-based panel industry. The manufacturing parameters were: a specific gravity of 0.8 and a rice straw content (10/90, 20/80 and 30/70 by wt.% of rice straw/waste tire particle). A commercial polyurethane adhesive for rubber was used as the composite binder. The water proof, water absorption and thickness swelling properties of the composite boards were better than those of wood particleboard. Furthermore, the flexibility and flexural properties of the composite boards were superior to those of other wood-based panel products. The composite boards also demonstrated good acoustical insulation, electrical insulation, anti-caustic and anti-rot properties. These boards can be used to prevent impact damage, are easily modifiable and are inexpensive. They are able to be used as a substitute for insulation boards and other flexural materials in construction.

Butyric acid fermentation of sodium hydroxide pretreated rice straw with undefined mixed culture.

Science.gov (United States)

Ai, Binling; Li, Jianzheng; Chi, Xue; Meng, Jia; Liu, Chong; Shi, En

2014-05-01

This study describes an alternative mixed culture fermentation technology to anaerobically convert lignocellulosic biomass into butyric acid, a valuable product with wide application, without supplementary cellulolytic enzymes. Rice straw was soaked in 1% NaOH solution to increase digestibility. Among the tested pretreatment conditions, soaking rice straw at 50°C for 72 h removed ~66% of the lignin, but retained ~84% of the cellulose and ~71% of the hemicellulose. By using an undefined cellulose-degrading butyrate-producing microbial community as butyric acid producer in batch fermentation, about 6 g/l of butyric acid was produced from the pretreated rice straw, which accounted for ~76% of the total volatile fatty acids. In the repeated-batch operation, the butyric acid production declined batch by batch, which was most possibly caused by the shift of microbial community structure monitored by denaturing gradient gel electrophoresis. In this study, batch operation was observed to be more suitable for butyric acid production.

Phytoremediation of arsenic contaminated paddy soils with Pteris vittata markedly reduces arsenic uptake by rice

International Nuclear Information System (INIS)

Ye Wenling; Khan, M. Asaduzzaman; McGrath, Steve P.; Zhao Fangjie

2011-01-01

Arsenic (As) accumulation in food crops such as rice is of major concern. To investigate whether phytoremediation can reduce As uptake by rice, the As hyperaccumulator Pteris vittata was grown in five contaminated paddy soils in a pot experiment. Over a 9-month period P. vittata removed 3.5-11.4% of the total soil As, and decreased phosphate-extractable As and soil pore water As by 11-38% and 18-77%, respectively. Rice grown following P. vittata had significantly lower As concentrations in straw and grain, being 17-82% and 22-58% of those in the control, respectively. Phytoremediation also resulted in significant changes in As speciation in rice grain by greatly decreasing the concentration of dimethylarsinic acid (DMA). In two soils the concentration of inorganic As in rice grain was decreased by 50-58%. The results demonstrate an effective stripping of bioavailable As from contaminated paddy soils thus reducing As uptake by rice. - Highlights: → Pteris vittata removed 3.5-11.4% of the total As from five contaminated paddy soils. → P. vittata decreased phosphate-extractable and soil solution As to a greater extent. → P. vittata reduced As concentration in rice grain by 18-83%. → P. vittata decreased methylated As in rice grain more than inorganic As. - Phytoremediation with P. vittata significantly reduced arsenic uptake by rice from contaminated paddy soils.

Phytoremediation of arsenic contaminated paddy soils with Pteris vittata markedly reduces arsenic uptake by rice

Energy Technology Data Exchange (ETDEWEB)

Ye Wenling [Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China); Khan, M. Asaduzzaman [Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka-1207 (Bangladesh); McGrath, Steve P. [Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Zhao Fangjie, E-mail: Fangjie.Zhao@bbsrc.ac.uk [Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom)

2011-12-15

Arsenic (As) accumulation in food crops such as rice is of major concern. To investigate whether phytoremediation can reduce As uptake by rice, the As hyperaccumulator Pteris vittata was grown in five contaminated paddy soils in a pot experiment. Over a 9-month period P. vittata removed 3.5-11.4% of the total soil As, and decreased phosphate-extractable As and soil pore water As by 11-38% and 18-77%, respectively. Rice grown following P. vittata had significantly lower As concentrations in straw and grain, being 17-82% and 22-58% of those in the control, respectively. Phytoremediation also resulted in significant changes in As speciation in rice grain by greatly decreasing the concentration of dimethylarsinic acid (DMA). In two soils the concentration of inorganic As in rice grain was decreased by 50-58%. The results demonstrate an effective stripping of bioavailable As from contaminated paddy soils thus reducing As uptake by rice. - Highlights: > Pteris vittata removed 3.5-11.4% of the total As from five contaminated paddy soils. > P. vittata decreased phosphate-extractable and soil solution As to a greater extent. > P. vittata reduced As concentration in rice grain by 18-83%. > P. vittata decreased methylated As in rice grain more than inorganic As. - Phytoremediation with P. vittata significantly reduced arsenic uptake by rice from contaminated paddy soils.

The effects of straw or straw-derived gasification biochar applications on soil quality and crop productivity

DEFF Research Database (Denmark)

Hansen, Veronika; Müller-Stöver, Dorette Sophie; Imparato, Valentina

2017-01-01

Thermal gasification of straw is a highly efficient technology that produces bioenergy and gasification biochar that can be used as a soil amendment, thereby returning non-renewable nutrients and stable carbon, and securing soil quality and crop productivity. A Danish on-farm field study investig......Thermal gasification of straw is a highly efficient technology that produces bioenergy and gasification biochar that can be used as a soil amendment, thereby returning non-renewable nutrients and stable carbon, and securing soil quality and crop productivity. A Danish on-farm field study...... investigated the impact of traditional straw incorporation vs. straw removal for thermal gasification bioenergy production and the application of straw gasification biochar (GB) on soil quality and crop production. Two rates of GB were applied over three successive years in which the field was cropped...... long-term effects and to identify the optimum balance between straw removal and biochar application rate....

Improved biogas production from rice straw by co-digestion with kitchen waste and pig manure

Energy Technology Data Exchange (ETDEWEB)

Ye, Jingqing [Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China); School of Environmental Sciences and Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Li, Dong; Sun, Yongming [Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China); Wang, Guohui [School of Environmental Sciences and Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Yuan, Zhenhong, E-mail: yuanzh@ms.giec.ac.cn [Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China); Zhen, Feng; Wang, Yao [Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640 (China)

2013-12-15

Highlights: • Biogas production was enhanced by co-digestion of rice straw with other materials. • The optimal ratio of kitchen waste, pig manure and rice straw is 0.4:1.6:1. • The maximum biogas yield of 674.4 L/kg VS was obtained. • VFA inhibition occurred when kitchen waste content was more than 26%. • The dominant VFA were propionate and acetate in successful reactors. - Abstract: In order to investigate the effect of feedstock ratios in biogas production, anaerobic co-digestions of rice straw with kitchen waste and pig manure were carried out. A series of single-stage batch mesophilic (37 ± 1 °C) anaerobic digestions were performed at a substrate concentration of 54 g/L based on volatile solids (VS). The results showed that the optimal ratio of kitchen waste, pig manure, and rice straw was 0.4:1.6:1, for which the C/N ratio was 21.7. The methane content was 45.9–70.0% and rate of VS reduction was 55.8%. The biogas yield of 674.4 L/kg VS was higher than that of the digestion of rice straw or pig manure alone by 71.67% and 10.41%, respectively. Inhibition of biogas production by volatile fatty acids (VFA) occurred when the addition of kitchen waste was greater than 26%. The VFA analysis showed that, in the reactors that successfully produced biogas, the dominant intermediate metabolites were propionate and acetate, while they were lactic acid, acetate, and propionate in the others.

Improved biogas production from rice straw by co-digestion with kitchen waste and pig manure

International Nuclear Information System (INIS)

Ye, Jingqing; Li, Dong; Sun, Yongming; Wang, Guohui; Yuan, Zhenhong; Zhen, Feng; Wang, Yao

2013-01-01

Highlights: • Biogas production was enhanced by co-digestion of rice straw with other materials. • The optimal ratio of kitchen waste, pig manure and rice straw is 0.4:1.6:1. • The maximum biogas yield of 674.4 L/kg VS was obtained. • VFA inhibition occurred when kitchen waste content was more than 26%. • The dominant VFA were propionate and acetate in successful reactors. - Abstract: In order to investigate the effect of feedstock ratios in biogas production, anaerobic co-digestions of rice straw with kitchen waste and pig manure were carried out. A series of single-stage batch mesophilic (37 ± 1 °C) anaerobic digestions were performed at a substrate concentration of 54 g/L based on volatile solids (VS). The results showed that the optimal ratio of kitchen waste, pig manure, and rice straw was 0.4:1.6:1, for which the C/N ratio was 21.7. The methane content was 45.9–70.0% and rate of VS reduction was 55.8%. The biogas yield of 674.4 L/kg VS was higher than that of the digestion of rice straw or pig manure alone by 71.67% and 10.41%, respectively. Inhibition of biogas production by volatile fatty acids (VFA) occurred when the addition of kitchen waste was greater than 26%. The VFA analysis showed that, in the reactors that successfully produced biogas, the dominant intermediate metabolites were propionate and acetate, while they were lactic acid, acetate, and propionate in the others

Effects of modified biochar on rhizosphere microecology of rice (Oryza sativa L.) grown in As-contaminated soil.

Science.gov (United States)

Liu, Shusi; Lu, Yixin; Yang, Chen; Liu, Chuanping; Ma, Lin; Dang, Zhi

2017-10-01

Biochar was carbon-rich and generated by high-temperature pyrolysis of biomass under oxygen-limited conditions. Due to the limitations of surface functional groups and the weakness of surface activity in the field of environmental remediation, the raw biochar frequently was chemically modified to improve its properties with a new performance. In this study, a kind of high-efficiency and low-cost amino biochar modified by nano zero-valent iron (ABC/NZVI) was synthesized and applied to paddy soil contaminated with arsenic (As). Dynamic changes of soil properties, arsenic speciations and rhizosphere microbial communities have been investigated over the whole growth period of rice plants. Pot experiments revealed that the ABC/NZVI could decrease the arsenic concentration in rice straw by 47.9% and increase the content of nitrogen in rice straw by 47.2%. Proportion of Geobacter in soil with ABC/NZVI treatment increased by 175% in tillering period; while Nitrososphaera decreased by 61 and 20% in tillering and maturity, respectively, compared to that of control. ABC/NZVI promotes arsenic immobilization in rhizosphere soil and precipitation on root surface and reduces arsenic accumulation in rice. At the same time, ABC/NZVI would inhibit Nitrososphaera which is related to ammonia oxidation process, and it would have a promising potential as soil amendment to reduce nitrogen loss probably.

Black liquor-derived carbonaceous solid acid catalyst for the hydrolysis of pretreated rice straw in ionic liquid.

Science.gov (United States)

Bai, Chenxi; Zhu, Linfeng; Shen, Feng; Qi, Xinhua

2016-11-01

Lignin-containing black liquor from pretreatment of rice straw by KOH aqueous solution was applied to prepare a carbonaceous solid acid catalyst, in which KOH played dual roles of extracting lignin from rice straw and developing porosity of the carbon material as an activation agent. The synthesized black liquor-derived carbon material was applied in catalytic hydrolysis of the residue solid from the pretreatment of rice straw, which was mainly composed of cellulose and hemicellulose, and showed excellent activity for the production of total reducing sugars (TRS) in ionic liquid, 1-butyl-3-methyl imidazolium chloride. The highest TRS yield of 63.4% was achieved at 140°C for 120min, which was much higher than that obtained from crude rice straw under the same reaction conditions (36.6% TRS yield). Overall, this study provides a renewable strategy for the utilization of all components of lignocellulosic biomass. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Effect of different organic fertilizers on bioavailability of soil Cd and Zn].

Science.gov (United States)

Xie, Yun-he; Ji, Xiong-hui; Wu, Jia-mei; Huang, Juan; Guan, Di; Zhu, Jian

2015-03-01

The active effect of soil Cd and Zn and their interaction was studied in typical paddy field in south China by monitoring the contents of Cd and Zn in soil and rice in rice fields applied with pig manure, chicken manure or rice straw for 4 years continuously. The results showed that applying pig manure, chicken manure or rice straw had no significant impact on the soil total Cd content, soil available Cd content and soil Cd activity, but tended to increase the soil total Cd content and increased the soil total Zn content, soil available Zn content and Zn activity significantly. Applications of pig manure, chicken manure and rice straw all reduced the Cd content of brown rice, in order of pig manure > chicken manure > rice straw. The Cd contents of brown rice, stem and leaf in the treatment applied with pig manure were lower than in the control by 37.5%, 44.0% and 36.4%, respectively; the Cd contents of brown rice, stem and leaf in the treatment applied with chicken manure were lower than in the control by 22.5%, 33.8%, and 22.7%, respectively; the Cd content of brown rice in the treatment applied with rice straw was lower than in the control by 7.5% but its contents in stem and leaf increased by 8.2% and 22.7% , respectively. The reduction in the brown rice Cd content was mainly due to the reduction of Cd enrichment from soil to brown rice after application of pig or chicken manure, but mainly due to the reduction of Cd transportation from stem to brown rice after straw application. Applications of pig manure, chicken manure and rice straw increased Zn contents in rice stem by 53.4%, 53.4% and 13.9%, respectively, but all had no significant effect on brown rice and leaf' s Zn contents. Zn and Cd had the significant antagonistic effects in the soil and rice stem. The increase of Zn content in soil and rice stem inhibited the adsorption and accumulation of Cd in the brown rice, stem and leaf significantly, and with the increase of the proportion of Zn/Cd, the

Utilization of organic fertilizer to increase paddy growth and productivity using System of Rice Intensification (SRI method in saline soil

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V . O . Subardja

2016-01-01

Full Text Available Soil salinity has negative effect on soil biodiversity as well as microbial activities. Hence, rice growth also effected by salinity. Application of organic fertilizer and adoption of System of Rice Intensification (SRI cultivation might improve the (biological soil properties and increase rice yield. The aim of this study was to evaluate the effect of two different rice cultivation methods namely conventional rice cultivation method and System of Rice Intensification (SRI rice cultivation method and two kinds organic fertilizer on improvement of soil biological properties and rice yield. In this study, a split plot experimental design was applied where rice cultivation method (conventional and SRI was the main plot and two kinds of organic fertilizer (market waste and rice straw was the sub plot. The treatments had four replicates. The results showed that SRI cultivation with market waste organic fertilizer could increase soil biological properties (population of microbe, fungi and soil respiration. The same treatment also increased rice growth and production. Combination of SRI and market waste organic fertilizer yielded the highest rice production (7.21 t/ha.

Simultaneous removal of cadmium and sulfamethoxazole from aqueous solution by rice straw biochar

Institute of Scientific and Technical Information of China (English)

Xuan HAN; Cheng-feng LIANG; Ting-qiang LI; Kai WANG; Hua-gang HUANG; Xiao-e YANG

2013-01-01

The simultaneous sorption behavior and characteristics of cadmium (Cd) and sulfamethoxazole (SMX) on rice straw biochar were investigated.Isotherms of Cd and SMX were well modeled by the Langmuir equation (R2>0.95).The calculated maximum adsorption parameter (Q) of Cd was similar in single and binary systems (34129.69 and 35919.54 mg/kg,respectively).However,the Q of SMX in a binary system (9182.74 mg/kg)was much higher than that in a single system (1827.82 mg/kg).The presence of Cd significantly promoted the sorption of SMX on rice straw biochar.When the pH ranged from 3 to 7.5,the sorption of Cd had the characteristics of a parabola pattern with maximum adsorption at pH 5,while the adsorption quantity of SMX decreased with increasing pH,with maximum adsorption at pH 3.The amount of SMX adsorbed on biochar was positively correlated with the surface area of the biochar,and the maximum adsorption occurred with d 250 biochar (biochar with a diameter of 150-250 μm).Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) showed that the removal of Cd and SMX by rice straw biochar may be attributed to precipitation and the formation of surface complexes between Cd or SMX and carboxyl or hydroxyl groups.The results of this study indicate that rice straw biochar has the potential for simultaneous removal of Cd and SMX from co-contaminated water.

Lovastatin-Enriched Rice Straw Enhances Biomass Quality and Suppresses Ruminal Methanogenesis

Directory of Open Access Journals (Sweden)

Mohammad Faseleh Jahromi

2013-01-01

Full Text Available The primary objective of this study was to test the hypothesis that solid state fermentation (SSF of agro-biomass (using rice straw as model; besides, breaking down its lignocellulose content to improve its nutritive values also produces lovastatin which could be used to suppress methanogenesis in the rumen ecosystem. Fermented rice straw (FRS containing lovastatin after fermentation with Aspergillus terreus was used as substrate for growth study of rumen microorganisms using in vitro gas production method. In the first experiment, the extract from the FRS (FRSE which contained lovastatin was evaluated for its efficacy for reduction in methane (CH4 production, microbial population, and activity in the rumen fluid. FRSE reduced total gas and CH4 productions (P<0.01. It also reduced (P<0.01 total methanogens population and increased the cellulolytic bacteria including Ruminococcus albus, Fibrobacter succinogenes (P<0.01, and Ruminococcus flavefaciens (P<0.05. Similarly, FRS reduced total gas and CH4 productions, methanogens population, but increased in vitro dry mater digestibility compared to the non-fermented rice straw. Lovastatin in the FRSE and the FRS significantly increased the expression of HMG-CoA reductase gene that produces HMG-CoA reductase, a key enzyme for cell membrane production in methanogenic Archaea.

Release of Polyphenols Is the Major Factor Influencing the Bioconversion of Rice Straw to Lactic Acid.

Science.gov (United States)

Chen, Xingxuan; Xue, Yiyun; Hu, Jiajun; Tsang, Yiu Fai; Gao, Min-Tian

2017-11-01

In this study, we found that p-coumaric acid (p-CA), ferulic acid (FA), and condensed tannins were released from rice straw during saccharification. The presence of polyphenols prolonged the lag phase and lowered the productivity of lactic acid. p-CA was identified as a key inhibitor. Tannins had a lower inhibitory effect than p-CA; FA had little inhibitory effect. Acid, alkaline, and ball milling pretreatments elicited different levels of polyphenol release from rice straw. Due to the different levels of polyphenol release in the pretreatment step, the enzymatic hydrolysates contained different concentrations of polyphenols. Compared with fermentation with a synthetic medium, fermentation with the hydrolysates of ball-milled rice straw provided much lower productivity and yield of lactic acid due to the presence of polyphenols. Removal of these compounds played an important role in lactic acid fermentation. When rice straw was alkaline pretreated, the hydrolysates contained few phenolic compounds, resulting in high productivity and yield of lactic acid (1.8 g/L/h and 26.7 g/100 g straw), which were comparable to those in a synthetic medium. This indicates that there is a correlation between removal of phenolic compounds and efficiency in lactic acid fermentation.

Rapid Preparation of Biosorbents with High Ion Exchange Capacity from Rice Straw and Bagasse for Removal of Heavy Metals

Directory of Open Access Journals (Sweden)

Supitcha Rungrodnimitchai

2014-01-01

Full Text Available This work describes the preparation of the cellulose phosphate with high ion exchange capacity from rice straw and bagasse for removal of heavy metals. In this study, rice straw and bagasse were modified by the reaction with phosphoric acid in the presence of urea. The introduced phosphoric group is an ion exchangeable site for heavy metal ions. The reaction by microwave heating yielded modified rice straw and modified bagasse with greater ion exchange capacities (∼3.62 meq/g and shorter reaction time (1.5–5.0 min than the phosphorylation by oil bath heating. Adsorption experiments towards Pb2+, Cd2+, and Cr3+ ions of the modified rice straw and the modified bagasse were performed at room temperature (heavy metal concentration 40 ppm, adsorbent 2.0 g/L. The kinetics of adsorption agreed with the pseudo-second-order model. It was shown that the modified rice straw and the modified bagasse could adsorb heavy metal ions faster than the commercial ion exchange resin (Dowax. As a result of Pb2+ sorption test, the modified rice straw (RH-NaOH 450W removed Pb2+ much faster in the initial step and reached 92% removal after 20 min, while Dowax (commercial ion exchange resin took 90 min for the same removal efficiency.

Modified Rice Straw as Adsorbent Material to Remove Aflatoxin B1 from Aqueous Media and as a Fiber Source in Fino Bread

OpenAIRE

Sherif R. Mohamed; Tarek A. El-Desouky; Ahmed M. S. Hussein; Sherif S. Mohamed; Khayria M. Naguib

2016-01-01

The aims of the current work are in large part the benefit of rice straw to be used as adsorbent material and natural source of fiber in Fino bread. The rice straw was subjected to high temperature for modification process and the chemical composition was carried out and the native rice straw contained about 41.15% cellulose, 20.46% hemicellulose, and 3.91% lignin while modified rice straw has 42.10, 8.65, and 5.81%, respectively. The alkali number was tested and showed an increase in the alk...

Soil bacterial community shifts associated with sugarcane straw removal

Science.gov (United States)

Pimentel, Laisa; Gumiere, Thiago; Andreote, Fernando; Cerri, Carlos

2017-04-01

In Brazil, the adoption of the mechanical unburned sugarcane harvest potentially increase the quantity of residue left in the field after harvesting. Economically, this material has a high potential for second generation ethanol (2G) production. However, crop residues have an essential role in diverse properties and processes in the soil. The greater part of the uncertainties about straw removal for 2G ethanol production is based on its effects in soil microbial community. In this sense, it is important to identify the main impacts of sugarcane straw removal on soil microbial community. Therefore, we conducted a field study, during one year, in Valparaíso (São Paulo state - Brazil) to evaluate the effects of straw decomposition on soil bacterial community. Specifically, we wanted: i) to compare the rates of straw removal and ii) to evaluate the effects of straw decomposition on soil bacterial groups over one year. The experiment was in a randomized block design with treatments arranged in strip plot. The treatments are different rates of sugarcane straw removal, namely: no removal, 50, 75 and 100% of straw removal. Soil sampling was carried out at 0, 4, 8 and 12 months after the sugarcane harvest (August 2015). Total DNA was extracted from soil using the PowersoilTM DNA Isolation kit. And the abundance of bacterial in each soil sample was estimated via quantification of 16S rRNA gene. The composition of the bacterial communities was estimated via terminal restriction fragment length polymorphism (T-RFLP) analysis, and the T-RF sizes were performed on a 3500 Genetic Analyzer. Finally, the results were examined with GeneMapper 4.1 software. There was bacterial community shifts through the time and among the rates of sugarcane straw removal. Bacterial community was firstly determined by the time scale, which explained 29.16% of total variation. Rates of straw removal explained 11.55% of shifts on bacterial community. Distribution through the time is an important

In situ rumen degradability characteristics of rice straw, soybean ...

African Journals Online (AJOL)

In situ rumen degradability characteristics of rice straw, soybean curd residue and peppermint (Mentha piperita) in Hanwoo steer (Bos Taurus coreanae). Byong Tae Jeon, KyoungHoon Kim, Sung Jin Kim, Na Yeon Kim, Jae Hyun Park, Dong Hyun Kim, Mi Rae Oh, Sang Ho Moon ...

Grain yield and arsenic uptake of upland rice inoculated with arbuscular mycorrhizal fungi in As-spiked soils.

Science.gov (United States)

Wu, Fuyong; Hu, Junli; Wu, Shengchun; Wong, Ming Hung

2015-06-01

A pot trial was conducted to investigate the effects of three arbuscular mycorrhizal (AM) fungi species, including Glomus geosporum BGC HUN02C, G. versiforme BGC GD01B, and G. mosseae BGC GD01A, on grain yield and arsenic (As) uptake of upland rice (Zhonghan 221) in As-spiked soils. Moderate levels of AM colonization (24.1-63.1 %) were recorded in the roots of upland rice, and up to 70 mg kg(-1) As in soils did not seem to inhibit mycorrhizal colonization. Positive mycorrhizal growth effects in grain, husk, straw, and root of the upland rice, especially under high level (70 mg kg(-1)) of As in soils, were apparent. Although the effects varied among species of AM fungi, inoculation of AM fungi apparently enhanced grain yield of upland rice without increasing grain As concentrations in As-spiked soils, indicating that AM fungi could alleviate adverse effects on the upland rice caused by As in soils. The present results also show that mycorrhizal inoculation significantly (p rice production when growing in As-contaminated soils.

Study on the Potential of Rice Straws as a Supplementary Fuel in Very Small Power Plants in Thailand

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Penwadee Cheewaphongphan

2018-01-01

Full Text Available Agricultural residue is a major raw material for renewable energy production, particularly heat production, in Thailand. Meanwhile, the process-based residue, such as bagasse, rice husk, wood residue, palm fiber, palm shell, and saw dust, is used as a fuel for energy production in the agro-industry. Hence, this study is intended to assess the net potential and capacity of alternative agricultural residues, specifically rice straws, to serve as the supplementary fuel for very small power plants (VSPPs in Thailand. According to the results obtained during the crop season of 2015/2016, approximately 26 Mt of rice straws were generated upon the harvesting process. The net potential of rice straws, including those that were burned and those that were left in the fields, was only about 15% or 3.85 Mt, which could be used for heat and electricity production at 1331 kilotons of oil equivalent (ktoe or 457 MWe. As agro-residues vary by seasonality, the peak season of rice straws was in November, where approximately 1.64 Mt (43% were generated, followed by December, at 1.32 Mt (34%. On the basis of the results, rice straw has the potential to serve as a fuel supply for VSPPs at 14.2%, 21.6%, 26.3%, and 29.0% for the radii of compilation at 24, 36, 48 km and 60 km, respectively.

Greenhouse gas emission analysis of an Egyptian rice straw biomass-to-energy chain

NARCIS (Netherlands)

Poppens, R.P.; Bakker, R.

2012-01-01

A common practice in Egypt has been the burning of rice straw, as a measure to prepare agricultural land for follow-up crops. This practice has caused significant greenhouse gas emissions, in addition to aerial pollution. By using straw residue for the production of pellets and shipping these

Effect of biochar and Fe-biochar on Cd and As mobility and transfer in soil-rice system.

Science.gov (United States)

Yin, Daixia; Wang, Xin; Peng, Bo; Tan, Changyin; Ma, Lena Q

2017-11-01

In this study, the effects of biochar derived from rice-straw (biochar) and iron-impregnated biochar (Fe-biochar) on Cd and As mobility in rice rhizosphere and transfer from soil to rice were investigated with different application rates. 1-3% biochar reduced porewater Cd in rhizosphere but elevated soluble As, resulting in 49-68% and 26-49% reduction in the root and grain Cd, with a simultaneous increase in root As. Unlike biochar, 0.5% Fe-biochar decreased porewater As throughout rice growth, resulting in reduced root As, which, however, increased Cd uptake by root. Biochar-induced soil As mobilization was probably through competitive desorption and Fe-biochar-induced soil Cd mobilization was probably via soil acidification. The results suggested that biochar and Fe-biochar was effective in reducing Cd and As uptake by rice, respectively, so they may be used as emergency measures to cope with single Cd or As contamination in paddy soils. Copyright © 2017. Published by Elsevier Ltd.

Energetic utilization and recycling of straw; Energetische und stoffliche Verwertung von Stroh

Energy Technology Data Exchange (ETDEWEB)

Schuech, Andrea; Engler, Nils; Weissbach, Gunter; Nelles, Michael [Rostock Univ. (Germany). Lehrstuhl Abfall- und Stoffstromwirtschaft

2013-10-01

Worldwide arising significant emissions caused by the burning of rice straw on the field. The combined energetic and material utilization of rice straw offers the production possibility of various usable bioenergy and the closing of nutrient cycles by the return of the conversion residues. Thereby the soil quality can be improved and an important contribution to climate protection and resource conservation be realized. In the German-Egyptian project CEMUWA, the options of material and energetic use of rice straw are investigated. It is used as substrate for plant cultivation and for the production of ethanol, butanol and biogas. In this paper first results are presented. (orig.)

Effect of oxalic acid and steam pretreatment on the primary properties of UF-bonded rice straw particleboards

Science.gov (United States)

Xianjun Li; Zhiyong Cai; Jerrold E. Winandy; Altaf H. Basta

2011-01-01

The objective is to evaluate the effect of oxalic acid (OA) and steam-pretreatment on the primary performance of rice straw particleboards. In addition, the effect of various treatment conditions on carbohydrates released from rice straw particles was investigated. The results show that steam- and short durations of OA-treatment significantly improved the mechanical...

Urea plus nitrate pretreatment of rice and wheat straws enhances degradation and reduces methane production in in vitro ruminal culture.

Science.gov (United States)

Zhang, Xiumin; Wang, Min; Wang, Rong; Ma, Zhiyuan; Long, Donglei; Mao, Hongxiang; Wen, Jiangnan; Bernard, Lukuyu A; Beauchemin, Karen A; Tan, Zhiliang

2018-04-10

Urea pretreatment of straw damages fiber structure, while nitrate supplementation of ruminal diets inhibits enteric methane production. The study examined the combined effects of these treatments on ruminal substrate biodegradation and methane production using an in vitro incubation system. Rice and wheat straws were pretreated with urea (40 g kg -1 straw dry matter, DM) and urea + ammonium nitrate (34 + 6 g kg -1 dry matter (DM), respectively), and each straw (control, urea, urea+nitrate) was used in batch culture incubations in three replications (runs). Urea pretreatment increased (P content (+17%) and in vitro DM degradation of rice straw, in comparison with control. Urea+nitrate pretreatment of rice and wheat straws had higher (P content, in vitro DM degradation and propionate molar proportion, and lower (P ruminal biodegradation, facilitate propionate production and reduce methane production from lignified straws. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Study on movement, accumulation and distribution of 137Cs in rice and soils

International Nuclear Information System (INIS)

Lu Zixian; Xu Shiming

1992-11-01

The experiment of growing rice contaminated by 137 Cs solution shows that from the seedling stage to booting stage the absorption rate of 137 Cs is the highest, in the heading stage it is steady and in the milk stage goes to high again. The 137 Cs transfers from root to straw and ear, and from vegetative organs to reproductive organs. The relationship between specific activity (SA) and the amount of 137 Cs in soil is proportional. Only when the amount of 137 Cs in soil reaches to 370 Bq/g the SA of 137 Cs in rice rises remarkably. The different soil growing rice has different absorption rate of 137 Cs. Only in Shenzhen it is much higher than in other areas. The absorption of 137 Cs is also depending on different stage, in the milk stage it is considerably higher than other stages

Co-composting of livestock manure with rice straw: characterization and establishment of maturity evaluation system.

Science.gov (United States)

Qian, Xiaoyong; Shen, Genxiang; Wang, Zhenqi; Guo, Chunxia; Liu, Yangqing; Lei, Zhongfang; Zhang, Zhenya

2014-02-01

Composting is considered to be a primary treatment method for livestock manure and rice straw, and high degree of maturity is a prerequisite for safe land application of the composting products. In this study pilot-scale experiments were carried out to characterize the co-composting process of livestock manure with rice straw, as well as to establish a maturity evaluation index system for the composts obtained. Two pilot composting piles with different feedstocks were conducted for 3 months: (1) swine manure and rice straw (SM-RS); and (2) dairy manure and rice straw (DM-RS). During the composting process, parameters including temperature, moisture, pH, total organic carbon (TOC), organic matter (OM), different forms of nitrogen (total, ammonia and nitrate), and humification index (humic acid and fulvic acid) were monitored in addition to germination index (GI), plant growth index (PGI) and Solvita maturity index. OM loss followed the first-order kinetic model in both piles, and a slightly faster OM mineralization was achieved in the SM-RS pile. Also, the SM-RS pile exhibited slightly better performance than the DM-RS according to the evolutions of temperature, OM degradation, GI and PGI. The C/N ratio, GI and PGI could be included in the maturity evaluation index system in which GI>120% and PGI>1.00 signal mature co-composts. Copyright © 2013 Elsevier Ltd. All rights reserved.

Chemical Pretreatment-Independent Saccharifications of Xylan and Cellulose of Rice Straw by Bacterial Weak Lignin-Binding Xylanolytic and Cellulolytic Enzymes.

Science.gov (United States)

Teeravivattanakit, Thitiporn; Baramee, Sirilak; Phitsuwan, Paripok; Sornyotha, Somphit; Waeonukul, Rattiya; Pason, Patthra; Tachaapaikoon, Chakrit; Poomputsa, Kanokwan; Kosugi, Akihiko; Sakka, Kazuo; Ratanakhanokchai, Khanok

2017-11-15

Complete utilization of carbohydrate fractions is one of the prerequisites for obtaining economically favorable lignocellulosic biomass conversion. This study shows that xylan in untreated rice straw was saccharified to xylose in one step without chemical pretreatment, yielding 58.2% of the theoretically maximum value by Paenibacillus curdlanolyticus B-6 PcAxy43A, a weak lignin-binding trifunctional xylanolytic enzyme, endoxylanase/β-xylosidase/arabinoxylan arabinofuranohydrolase. Moreover, xylose yield from untreated rice straw was enhanced to 78.9% by adding endoxylanases PcXyn10C and PcXyn11A from the same bacterium, resulting in improvement of cellulose accessibility to cellulolytic enzyme. After autoclaving the xylanolytic enzyme-treated rice straw, it was subjected to subsequent saccharification by a combination of the Clostridium thermocellum endoglucanase CtCel9R and Thermoanaerobacter brockii β-glucosidase TbCglT, yielding 88.5% of the maximum glucose yield, which was higher than the glucose yield obtained from ammonia-treated rice straw saccharification (59.6%). Moreover, this work presents a new environment-friendly xylanolytic enzyme pretreatment for beneficial hydrolysis of xylan in various agricultural residues, such as rice straw and corn hull. It not only could improve cellulose saccharification but also produced xylose, leading to an improvement of the overall fermentable sugar yields without chemical pretreatment. IMPORTANCE Ongoing research is focused on improving "green" pretreatment technologies in order to reduce energy demands and environmental impact and to develop an economically feasible biorefinery. The present study showed that PcAxy43A, a weak lignin-binding trifunctional xylanolytic enzyme, endoxylanase/β-xylosidase/arabinoxylan arabinofuranohydrolase from P. curdlanolyticus B-6, was capable of conversion of xylan in lignocellulosic biomass such as untreated rice straw to xylose in one step without chemical pretreatment. It

The kinetics of glucose production from rice straw by Aspergillus niger

African Journals Online (AJOL)

STORAGESEVER

2008-06-03

Jun 3, 2008 ... The concentration and rate of glucose production was observed to depend on pretreatment of ... cerning reaction rate parameters for rice straw hydrolysis. The generation of such ... The experiment and glucose analysis was ...

Genetic Control of a Transition from Black to Straw-White Seed Hull in Rice Domestication1[C][W][OA

Science.gov (United States)

Zhu, Bo-Feng; Si, Lizhen; Wang, Zixuan; Jingjie Zhu, Yan Zhou; Shangguan, Yingying; Lu, Danfeng; Fan, Danlin; Li, Canyang; Lin, Hongxuan; Qian, Qian; Sang, Tao; Zhou, Bo; Minobe, Yuzo; Han, Bin

2011-01-01

The genetic mechanism involved in a transition from the black-colored seed hull of the ancestral wild rice (Oryza rufipogon and Oryza nivara) to the straw-white seed hull of cultivated rice (Oryza sativa) during grain ripening remains unknown. We report that the black hull of O. rufipogon was controlled by the Black hull4 (Bh4) gene, which was fine-mapped to an 8.8-kb region on rice chromosome 4 using a cross between O. rufipogon W1943 (black hull) and O. sativa indica cv Guangluai 4 (straw-white hull). Bh4 encodes an amino acid transporter. A 22-bp deletion within exon 3 of the bh4 variant disrupted the Bh4 function, leading to the straw-white hull in cultivated rice. Transgenic study indicated that Bh4 could restore the black pigment on hulls in cv Guangluai 4 and Kasalath. Bh4 sequence alignment of all taxa with the outgroup Oryza barthii showed that the wild rice maintained comparable levels of nucleotide diversity that were about 70 times higher than those in the cultivated rice. The results from the maximum likelihood Hudson-Kreitman-Aguade test suggested that the significant reduction in nucleotide diversity in rice cultivars could be caused by artificial selection. We propose that the straw-white hull was selected as an important visual phenotype of nonshattered grains during rice domestication. PMID:21263038

Paddy-field contamination with 134Cs and 137Cs due to Fukushima Dai-ichi Nuclear Power Plant accident and soil-to-rice transfer coefficients

International Nuclear Information System (INIS)

Endo, Satoru; Kajimoto, Tsuyoshi; Shizuma, Kiyoshi

2013-01-01

The transfer coefficient (TF) from soil to rice plants of 134 Cs and 137 Cs in the form of radioactive deposition from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in March 2011 was investigated in three rice paddy fields in Minami-Soma City. Rice crops were planted in the following May and harvested at the end of September. Soil cores of 30-cm depth were sampled from rice-planted paddy fields to measure 134 Cs and 137 Cs radioactivity at 5-cm intervals. 134 Cs and 137 Cs radioactivity was also measured in rice ears (rice with chaff), straws and roots. The rice ears were subdivided into chaff, brown rice, polished rice and rice bran, and the 134 Cs and 137 Cs radioactivity concentration of each plant part was measured to calculate the respective TF from the soil. The TF of roots was highest at 0.48 ± 0.10 in the field where the 40 K concentration in the soil core was relatively low, in comparison with TF values of 0.31 and 0.38 in other fields. Similar trends could be found for the TF of whole rice plants, excluding roots. The TF of rice ears was relatively low at 0.019–0.026. The TF of chaff, rice bran, brown rice and polished rice was estimated to be 0.049, 0.10–0.16, 0.013–0.017 and 0.005–0.013, respectively. - Highlights: ► We investigated the transfer coefficient of 134 Cs and 137 Cs from soil to rice plants in Minami-Soma City due to the Fukushima accident in 2011. ► The rice ears, straws, roots, chaff, brown rice, polished rice, rice bran and soil samples have been measured by Ge-detector. ► Transfer coefficient of chaff, rice bran, brown rice, and polished rice is estimated as 0.049, ranging from 0.10 to 0.16, 0.013 to 0.017, and 0.005 to 0.013, respectively.

Inhibition experiments on nitrous oxide emission from paddy soils

Science.gov (United States)

Xu, Xingkai; Boeckx, Pascal; Zhou, Likai; Van Cleemput, Oswald

2002-08-01

Rice fields using nitrogen-based fertilizers play an important role in the global N2O budget. However, our knowledge is still limited with regard to the mechanisms affecting the N2O emission and to the measures that can reduce the emission. This paper reports a study of N2O emission from paddy soils. The effects of urea, hydroquinone (HQ, a urease inhibitor), and dicyandiamide (DCD, a nitrification inhibitor) have been studied in pot experiments with and without rice plants and with and without addition of wheat straw. With no wheat straw amendment, all treatments with inhibitors, especially with HQ + DCD, had a much smaller N2O emission during the rice growing period than the urea treatment, whereas a substantially increased N2O emission was observed from a rice-free soil with inhibitors. The N2O emission from the rice-planted soil was exponentially positive correlated with the NO3--N concentration in the rice aboveground biomass. By comparing the total N2O emission from the rice-free soil and from the rice-planted soil, we found that urea application alone might induce an apparent plant-mediated N2O emission, being 0.39 +/- 0.08% of the applied urea N. Wheat straw incorporated into the flooded surface layer soil could increase the plant-mediated N2O emission significantly. However, application of HQ + DCD could reduce this emission (0.27 +/- 0.08% of the applied urea N, compared with 0.89 +/- 0.18% in the urea treatment). It also reduced the N2O emission from the rice-free soil and from the rice-planted soil. Stepwise regression analysis indicates that denitrification in the flooded surface layer soil was the main source of N2O emission from this wetland rice cultivation, particularly when wheat straw was added. A significantly nonlinear negative relation was found between the N2O emission and the CH4 emission when no wheat straw was added, but it was hard to quantify this trade-off relation when wheat straw was incorporated into the flooded surface layer soil.

Effects of ditch-buried straw return on water percolation, nitrogen leaching and crop yields in a rice-wheat rotation system.

Science.gov (United States)

Yang, Haishui; Xu, Mingmin; Koide, Roger T; Liu, Qian; Dai, Yajun; Liu, Ling; Bian, Xinmin

2016-03-15

Crop residue management and nitrogen loss are two important environmental problems in the rice-wheat rotation system in China. This study investigated the effects of burial of straw on water percolation, nitrogen loss by leaching, crop growth and yield. Greenhouse mesocosm experiments were conducted over the course of three simulated cropping seasons in a rice1-wheat-rice2 rotation. Greater amounts of straw resulted in more water percolation, irrespective of crop season. Burial at 20 and 35 cm significantly reduced, but burial at 50 cm increased nitrogen leaching. Straw at 500 kg ha(-1) reduced, but at 1000 kg ha(-1) and at 1500 kg ha(-1) straw increased nitrogen leaching in three consecutive crop rotations. In addition, straw at 500 kg ha(-1) buried at 35 cm significantly increased yield and its components for both crops. This study suggests that N losses via leaching from the rice-wheat rotation may be reduced by the burial of the appropriate amount of straw at the appropriate depth. Greater amounts of buried straw, however, may promote nitrogen leaching and negatively affect crop growth and yields. Complementary field experiments must be performed to make specific agronomic recommendations. © 2015 Society of Chemical Industry.

A two-stage bioprocess for hydrogen and methane production from rice straw bioethanol residues.

Science.gov (United States)

Cheng, Hai-Hsuan; Whang, Liang-Ming; Wu, Chao-Wei; Chung, Man-Chien

2012-06-01

This study evaluates a two-stage bioprocess for recovering hydrogen and methane while treating organic residues of fermentative bioethanol from rice straw. The obtained results indicate that controlling a proper volumetric loading rate, substrate-to-biomass ratio, or F/M ratio is important to maximizing biohydrogen production from rice straw bioethanol residues. Clostridium tyrobutyricum, the identified major hydrogen-producing bacteria enriched in the hydrogen bioreactor, is likely utilizing lactate and acetate for biohydrogen production. The occurrence of acetogenesis during biohydrogen fermentation may reduce the B/A ratio and lead to a lower hydrogen production. Organic residues remained in the effluent of hydrogen bioreactor can be effectively converted to methane with a rate of 2.8 mmol CH(4)/gVSS/h at VLR of 4.6 kg COD/m(3)/d. Finally, approximately 75% of COD in rice straw bioethanol residues can be removed and among that 1.3% and 66.1% of COD can be recovered in the forms of hydrogen and methane, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

A Field Experiment on Enhancement of Crop Yield by Rice Straw and Corn Stalk-Derived Biochar in Northern China

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Yang Yang

2015-10-01

Full Text Available Biochar, a green way to deal with burning and burying biomass, has attracted more attention in recent years. To fill the gap of the effects of different biochar on crop yield in Northern China, the first field experiment was conducted in farmland located in Hebei Province. Biochars derived from two kinds of feedstocks (rice straw and corn stalk were added into an Inceptisols area with different dosages (1 ton/ha, 2 ton/ha or 4 ton/ha in April 2014. The crop yields were collected for corn, peanut, and sweet potato during one crop season from spring to autumn 2014, and the wheat from winter 2014 to summer 2015, respectively. The results showed biochar amendment could enhance yields, and biochar from rice straw showed a more positive effect on the yield of corn, peanut, and winter wheat than corn stalk biochar. The dosage of biochar of 2 ton/ha or 1 ton/ha could enhance the yield by 5%–15% and biochar of 4 ton/ha could increase the yield by about 20%. The properties of N/P/K, CEC, and pH of soils amended with biochar were not changed, while biochar effects could be related to improvement of soil water content.

Direct ethanol production from starch, wheat bran and rice straw by the white rot fungus Trametes hirsuta.

Science.gov (United States)

Okamoto, Kenji; Nitta, Yasuyuki; Maekawa, Nitaro; Yanase, Hideshi

2011-03-07

The white rot fungus Trametes hirsuta produced ethanol from a variety of hexoses: glucose, mannose, cellobiose and maltose, with yields of 0.49, 0.48, 0.47 and 0.47 g/g of ethanol per sugar utilized, respectively. In addition, this fungus showed relatively favorable xylose consumption and ethanol production with a yield of 0.44 g/g. T. hirsuta was capable of directly fermenting starch, wheat bran and rice straw to ethanol without acid or enzymatic hydrolysis. Maximum ethanol concentrations of 9.1, 4.3 and 3.0 g/l, corresponding to 89.2%, 78.8% and 57.4% of the theoretical yield, were obtained when the fungus was grown in a medium containing 20 g/l starch, wheat bran or rice straw, respectively. The fermentation of rice straw pretreated with ball milling led to a small improvement in the ethanol yield: 3.4 g ethanol/20 g ball-milled rice straw. As T. hirsuta is an efficient microorganism capable of hydrolyzing biomass to fermentable sugars and directly converting them to ethanol, it may represent a suitable microorganism in consolidated bioprocessing applications. Copyright © 2010 Elsevier Inc. All rights reserved.

A feasibility study of hydrothermal treatment of rice straw for multi-production of solid fuel and liquid fertilizer

Science.gov (United States)

Samnang, S.; Prawisudha, P.; Pasek, A. D.

2017-05-01

Energy use has increased steadily over the last century due to population and industry increase. With the growing of GHG, biomass becomes an essential contributor to the world energy need. Indonesia is the third rice producer in the world. Rice straw has been converted to solid fuel by Hydrothermal Treatment (HT) for electricity generation. HT is a boiling solid organic or inorganic substance in water at high pressure and temperature within a holding time. HT converts high moisture content biomass into dried, uniform, pulverized, and higher energy density solid fuels. HT can effectively transport nutrient components in biomass into a liquid product known as fertilizer. This paper deals with an evaluation of hydrothermal treatment of rice straw for solid fuel and liquid fertilizer. An investigation of rice straw characteristics were completed for Bandung rice straw with various condition of temperature, biomass-water ratio, and holding time in the purpose to find the changes of calorific value for solid product and (N, P, K, and pH) for liquid product. The results showed that solid product at 225 °C and 90 min consists in a heating value 13.8 MJ/kg equal to lignite B. Liquid product at 225 °C and 90 min had the NPK content similar to that of micronutrients compound liquid fertilizer. The dried solid product should be useful for Coal Fire Power Plant, and the liquid product is suitable for plants. This research proves that hydrothermal process can be applied to rice straw to produce solid fuel and liquid fertilizer with adequate quality.

Gasification of rice straw in a fluidized-bed gasifier for syngas application in close-coupled boiler-gasifier systems.

Science.gov (United States)

Calvo, L F; Gil, M V; Otero, M; Morán, A; García, A I

2012-04-01

The feasibility and operation performance of the gasification of rice straw in an atmospheric fluidized-bed gasifier was studied. The gasification was carried out between 700 and 850 °C. The stoichiometric air-fuel ratio (A/F) for rice straw was 4.28 and air supplied was 7-25% of that necessary for stoichiometric combustion. Mass and power balances, tar concentration, produced gas composition, gas phase ammonia, chloride and potassium concentrations, agglomeration tendencies and gas efficiencies were assessed. Agglomeration was avoided by replacing the normal alumina-silicate bed by a mixture of alumina-silicate sand and MgO. It was shown that it is possible to produce high quality syngas from the gasification of rice straw. Under the experimental conditions used, the higher heating value (HHV) of the produced gas reached 5.1 MJ Nm(-3), the hot gas efficiency 61% and the cold gas efficiency 52%. The obtained results prove that rice straw may be used as fuel for close-coupled boiler-gasifier systems. Copyright © 2012 Elsevier Ltd. All rights reserved.

Rice lands of South and South East Asia, some soil physical aspects

International Nuclear Information System (INIS)

Bhagat, R.M.

2004-01-01

in a lowland-upland (e.g. rice-wheat) situation because of soil shrinkage. Change in the orientation of soil particles in puddled layer brings about changes in soil porosity. The parallel oriented structure produced following puddling from an initially open gel structure, total porosity will decrease. Total pore volume may, however, temporarily increase upon puddling. But an ultimate decline in total porosity is noticed upon puddling in many studies. Depending upon the soil texture and the initial aggregation status at low soil water potential (more negative), water retention in puddled soils is always higher then the non puddle soil. In a long term study on rice straw management in lowland rice - upland wheat system, it was observed that water retention was always higher in plots which were puddle in a previous rice compared to the non puddle plots, even if these were supplied with straw mulch or farm yard manure in the following upland wheat crop. Thermal regimes of air, flood water and soil monitored for diurnal variations in temperature, indicate that for flood water as well as soil, the puddled plots always maintained a higher temperature compared to non puddle plots. Increase in temperature following puddling is attributed to a decrease in percolation rates. In puddled plots water continue to pond on the surface for longer periods compared to non puddled plots resulting in an increase in temperature

Ammonia volatilization and atmospheric N deposition following straw and urea application from a rice-wheat rotation in southeastern China

Science.gov (United States)

Sun, Liying; Wu, Zhen; Ma, Yuchun; Liu, Yinglie; Xiong, Zhengqin

2018-05-01

Ammonia is a vital component of the nitrogen (N) cycle of terrestrial ecosystems in terms of volatilization and deposition. Here, a field experiment was undertaken to simultaneously investigate the effects of rice straw and urea incorporation on ammonia volatilization, atmospheric N deposition, yields and agronomic nitrogen use efficiency (NUE) under a rice-wheat system in China. The experiment involved four treatments: control (0 N, 0 straw), NS0 (250 kg N ha-1 season-1, 0 straw), NS1 (250 kg N ha-1 season-1, 3 t ha-1 yr-1 straw), and NS2 (250 kg N ha-1 season-1, 6 t ha-1 yr-1 straw) in the rice-wheat annual rotation system. The results indicated that the NS0, NS1 and NS2 treatments emitted cumulative ammonia of 14.0%, 16.4%, and 19.2%, respectively in the rice season and 7.6%, 11.1%, and 12.3%, respectively in the wheat season among the total urea-N application. Compared to the NS0 treatment, the NS1 and NS2 treatments significantly increased the cumulative ammonia emissions by 15.5% (p NH4+-N deposition accounted for 56.1% of the total inorganic N deposition during the whole rice-wheat system. The bulk NH4+-N deposition during the period of fertilization contributed 73.9% and 5.7% to the total NH4+-N deposition in the rice and wheat season, respectively. Overall, straw incorporation increased ammonia volatilization, not affecting the crop grain yield or NUE. The seasonal variation in NH4+-N bulk deposition was closely related to N fertilizer application.

Prokaryote community dynamics in anaerobic co-digestion of swine manure, rice straw and industrial clay residuals.

Science.gov (United States)

Jiménez, Janet; Theuerl, Susanne; Bergmann, Ingo; Klocke, Michael; Guerra, Gilda; Romero-Romero, Osvaldo

The aim of this study was to analyze the effect of the addition of rice straw and clay residuals on the prokaryote methane-producing community structure in a semi-continuously stirred tank reactor fed with swine manure. Molecular techniques, including terminal restriction fragment length polymorphism and a comparative nucleotide sequence analyses of the prokaryotic 16S rRNA genes, were performed. The results showed a positive effect of clay addition on methane yield during the co-digestion of swine manure and rice straw. At the digestion of swine manure, the bacterial phylum Firmicutes and the archaeal family Methanosarcinaceae, particularly Methanosarcina species, were predominant. During the co-digestion of swine manure and rice straw the microbial community changed, and with the addition of clay residual, the phylum Bacteroidetes predominated. The new nutritional conditions resulted in a shift in the archaeal family Methanosarcinaceae community as acetoclastic Methanosaeta species became dominant.

Rice straw as a renewable energy source in India, Thailand, and the Philippines: Overall potential and limitations for energy contribution and greenhouse gas mitigation

International Nuclear Information System (INIS)

Gadde, Butchaiah; Menke, Christoph; Wassmann, Reiner

2009-01-01

abstract: Rice is a widely grown crop in the South and South-East Asia that leaves substantial quantity of straw in the field. The aim of this paper is to assess the quantity of rice straw produced, estimate Greenhouse Gas (GHG) emissions based on its current uses, and assess its possible energy potential and related GHG emissions mitigation potential. Updated statistics on rough rice production are used in this study in combination with the literature values on Straw-to-Grain Ratio (SGR) to quantify the amount of rice straw produced in the three countries of focus. It is estimated that 97.19, 21.86, and 10.68 Mt of rice straw residue are produced in India, Thailand, and the Philippines, respectively. In India, 23% of rice straw residue produced is surplus and is either left in the field as uncollected or to a large extent open-field burnt. About 48% of this residue produced is subjected to open-field burning in Thailand, and in the Philippines it is 95%. The GHG emissions contribution through open-field burning of rice straw in India, Thailand, and the Philippines are 0.05%, 0.18%, and 0.56%, and the mitigated GHG emissions when generated electricity is used would be 0.75%, 1.81%, and 4.31%, respectively, when compared to the total country GHG emissions.

Involvement of Fenton chemistry in rice straw degradation by the lignocellulolytic bacterium Pantoea ananatis Sd-1.

Science.gov (United States)

Ma, Jiangshan; Zhang, Keke; Huang, Mei; Hector, Stanton B; Liu, Bin; Tong, Chunyi; Liu, Qian; Zeng, Jiarui; Gao, Yan; Xu, Ting; Liu, Ying; Liu, Xuanming; Zhu, Yonghua

2016-01-01

Lignocellulolytic bacteria have revealed to be a promising source for biofuel production, yet the underlying mechanisms are still worth exploring. Our previous study inferred that the highly efficient lignocellulose degradation by bacterium Pantoea ananatis Sd-1 might involve Fenton chemistry (Fe 2+  + H 2 O 2  + H +  → Fe 3+  + OH· + H 2 O), similar to that of white-rot and brown-rot fungi. The aim of this work is to investigate the existence of this Fenton-based oxidation mechanism in the rice straw degradation process of P. ananatis Sd-1. After 3 days incubation of unpretreated rice straw with P. ananatis Sd-1, the percentage in weight reduction of rice straw as well as its cellulose, hemicellulose, and lignin components reached 46.7, 43.1, 42.9, and 37.9 %, respectively. The addition of different hydroxyl radical scavengers resulted in a significant decline ( P  Fenton reagent treatment. In addition to the increased total iron ion concentration throughout the rice straw decomposition process, the Fe 3+ -reducing capacity of P. ananatis Sd-1 was induced by rice straw and predominantly contributed by aromatic compounds metabolites. The transcript levels of the glucose-methanol-choline oxidoreductase gene related to hydrogen peroxide production were significantly up-regulated (at least P  Fenton-like reactions. Our results confirmed the Fenton chemistry-assisted degradation model in P. ananatis Sd-1. We are among the first to show that a Fenton-based oxidation mechanism exists in a bacteria degradation system, which provides a new perspective for how natural plant biomass is decomposed by bacteria. This degradative system may offer an alternative approach to the fungi system for lignocellulosic biofuels production.

Effects of straw mulching on soil evaporation during the soil thawing ...

Indian Academy of Sciences (India)

26

Keywords: straw mulching, soil water evaporation, soil thawing period, freezing depth, soil liquid water .... moisture and the soil water evaporation process. The Songnen Plain ...... soils on soil infiltration and evaporation: Water Sci. Technol.

Degradation of lignocelluloses in rice straw by BMC-9, a composite microbial system.

Science.gov (United States)

Zhao, Hongyan; Yu, Hairu; Yuan, Xufeng; Piao, Renzhe; Li, Hulin; Wang, Xiaofen; Cui, Zongjun

2014-05-01

To evaluate the potential utility of pretreatment of raw biomass with a complex microbial system, we investigated the degradation of rice straw by BMC-9, a lignocellulose decomposition strain obtained from a biogas slurry compost environment. The degradation characteristics and corresponding changes in the bacterial community were assessed. The results showed that rapid degradation occurred from day 0 to day 9, with a peak total biomass bacterium concentration of 3.3 × 10(8) copies/ml on day 1. The pH of the fermentation broth declined initially and then increased, and the mass of rice straw decreased steadily. The highest concentrations of volatile fatty acid contents (0.291 mg/l lactic acid, 0.31 mg/l formic acid, 1.93 mg/l acetic acid, and 0.73 mg/l propionic acid) as well as the highest xylanse activity (1.79 U/ml) and carboxymethyl cellulase activity (0.37 U/ml) occurred on day 9. The greatest diversity among the microbial community also occurred on day 9, with the presence of bacteria belonging to Clostridium sp., Bacillus sp., and Geobacillus sp. Together, our results indicate that BMC-9 has a strong ability to rapidly degrade the lignocelluloses of rice straw under relatively inexpensive conditions, and the optimum fermentation time is 9 days.

Properties and Possible Applications for Lignin Streams Obtained from Rice Straw Processing

DEFF Research Database (Denmark)

Mussatto, Solange I.

This study aimed to evaluate the chemical and physical properties of lignin streams recovered from rice straw processing and to study the extraction of antioxidant phenolic compounds from these materials. The evaluated samples included two different cellulignin fermentation residues (FR’s) and an......This study aimed to evaluate the chemical and physical properties of lignin streams recovered from rice straw processing and to study the extraction of antioxidant phenolic compounds from these materials. The evaluated samples included two different cellulignin fermentation residues (FR......’s) and an acid-precipitated lignin from alkaline-deacetylated black liquor (DBLL). For comparison, a standard lignin sample (Kraft lignin, from Sigma-Aldrich) was also assayed. Besides providing a better understanding about such materials, the obtained results made also possible to propose some potential...

Exergetic analysis of a steam power plant using coal and rice straw in a co-firing process

Energy Technology Data Exchange (ETDEWEB)

Restrepo, Alvaro; Miyake, Raphael Guardini; Bazzo, Edson [Federal University of Santa Catarina (UFSC), Dept. of Mechanical Engineering, Florianopolis, SC (Brazil)], e-mails: arestrep@labcet.ufsc.br, miyake@labcet.ufsc.br, ebazzo@emc.ufsc.br; Bzuneck, Marcelo [Tractebel Energia S.A., Capivari de Baixo, SC (Brazil). U.O. Usina Termeletrica Jorge Lacerda C.], e-mail: marcelob@tractebelenergia.com.br

2010-07-01

This paper presents an exergetic analysis concerning an existing 50 M We steam power plant, which operates with pulverized coal from Santa Catarina- Brazil. In this power plant, a co-firing rice straw is proposed, replacing up to 10% of the pulverized coal in energy basis required for the boiler. Rice straw has been widely regarded as an important source for bio-ethanol, animal feedstock and organic chemicals. The use of rice straw as energy source for electricity generation in a co-firing process with low rank coal represents a new application as well as a new challenge to overcome. Considering both scenarios, the change in the second law efficiency, exergy destruction, influence of the auxiliary equipment and the greenhouse gases emissions such as CO{sub 2} and SO{sub 2} were considered for analysis. (author)

Nitrogen Fertilizer and Straw Applications Affect Uptake of 13C,15N-Glycine by Soil Microorganisms in Wheat Growth Stages.

Directory of Open Access Journals (Sweden)

Lijie Yang

Full Text Available This study investigated the influence of nitrogen (N fertilizer and straw on intact amino acid N uptake by soil microorganisms and the relationship between amino acid turnover and soil properties during the wheat growing season. A wheat pot experiment was carried out with three treatments: control (CK, N fertilizer (NF and N fertilizer plus rice straw (NS. We used stable isotope compound-specific analysis to determine the uptake of 13C,15N-glycine by soil microorganisms. In the NF treatment, microbial 13C,15N-glycine uptake was lower compared with CK, suggesting that inorganic N was the preferred N source for soil microorganisms. However, The application of straw with N fertilizer (in NS treatment increased microbial 13C,15N-glycine uptake even with the same amount of N fertilizer application. In this treatment, enzyme activities, soil microbial biomass C and microbial biomass N increased simultaneously because more C was available. Soil mineral N and plant N contents all decreased substantially. The increased uptake of intact 13C,15N-glycine in the NS treatment can be attributed to direct assimilation by soil microorganisms to satisfy the demand for N when inorganic N was consumed.

Effects of sodium carbonate pretreatment on the chemical compositions and enzymatic saccharification of rice straw.

Science.gov (United States)

Yang, Linfeng; Cao, Jie; Jin, Yongcan; Chang, Hou-min; Jameel, Hasan; Phillips, Richard; Li, Zhongzheng

2012-11-01

The effects of sodium carbonate (Na(2)CO(3)) pretreatment on the chemical compositions and enzymatic saccharification of rice straw were investigated. The enzymatic digestibility of rice straw is enhanced after pretreatment since pretreated solids show significant delignification with high sugar availability. During pretreatment, an increasing temperature and Na(2)CO(3) charge leads to enhanced delignification, whereas an increased degradation of polysaccharides as well, of which xylan acts more susceptible than glucan. The sugar recovery of enzymatic hydrolysis goes up rapidly with the total titratable alkali (TTA) increasing from 0% to 8%, and then it reaches a plateau. The highest sugar recovery of rice straw after pretreatment, 71.7%, 73.2%, and 76.1% for total sugar, glucan, and xylan, respectively, is obtained at 140°C, TTA 8% and cellulase loading of 20 FPU/g-cellulose. In this condition, the corresponding delignification ratio of pretreated solid is 41.8%, while 95% of glucan and 76% of xylan are conserved. Copyright © 2012 Elsevier Ltd. All rights reserved.

Improvement of Rice Straw for Ruminant Feed Through Unconventional Alkali Treatment and Supplementation of Various Protein Sources

Directory of Open Access Journals (Sweden)

SNO Suwandyastuti

2010-05-01

Full Text Available Various chemical treatments were conducted to increase the utilization of rice straw as feed for ruminant animals. Various sources of protein, minerals and energy should be added to improve the nutritive value of feeds. Two experiments were conducted in this study. The objective of the first experiments was to study the effect of chemical treatment on the ruminal fermentation products in cattle. Unconventional alkali treatment made from filtrate of a 10% rice hulls ash solution enriched with urea and minerals (treatment 1 increased volatile fatty acid (VFA production, ammonia nitrogen (NH3-N and rumen microbial protein synthesis (MPS. The maximum values of NH3-N production and rumen microbial protein synthesis were reached at 4 hours after incubation, while VFA was reached at 6 hours. The second experiment was conducted to study the increase of nutritive value of rice straw previously treated in experiment 1 through supplementation with various protein sources. Protein sources from the residues of vegetative oil production such as coconut, peanut and soybean showed higher responses compared to soy-sauce making residue and tofu making residue. The protein effluent production was highest (2.19 g/d at a VFA/NH3-N ration of 37.74 (r = 0.912. It can be recommended that protein sources from agro-industrial wastes can be used to increase the nutritive value and utilization of rice straw as ruminant feed. (Animal Production 12(2: 82-85 (2010Key Words: rice straw, rumen, fermentation

The balance of distribution and conversion of pentachlorophenal 14C in rice plants and soil

International Nuclear Information System (INIS)

Weiss, U.; Scheunert, I.; Korte, F.

1981-01-01

Rice plants were cultivated in a climatic chamber in vessels with 7-8 kg soil which was contaminated with 14 C pentachlorophenol. The soil was flooded with water during the growth period. The test was carried out until the rice plants were ripe. All parts of the system (atmosphere, straw and ears, roots and stubble, infiltration water, soil and washing water from the roots) were then investigated for their 14 C content. It could be seen that pentachlorophenol does not belong to the so-called 'persistant' environmental chemicals. After a period of vegetation, only about 1% of the initial substance is found in the plant/soil system. Besides the volatility of the initial substance and/or decomposition products into the atmosphere, a stepwise reductive dechlorination takes place in the soil and plants and finally the residues are bonded in a specific form to soil and plants. Residues can occur in the rice grains after soil treatment of rice cultures which also are largely bonded and cannot be chemically characterized. Its toxicological significance has not been thoroughly investigated. The question of the long-term consequences of the bonded residues still needs extensive research despite the favourable conclusion that can be drawn from this study on environmental behaviour of pentachlorophenol. (orig.) [de

Effect of chemically processed bonemeal alone and in combination with organic materials on plant growth. [Part] I : Rice-wheat rotation in an alluvial soil

International Nuclear Information System (INIS)

Ramasami, S.; Vimal, O.P.

1975-01-01

The effect of chemically processed bonemeal added 60 kg P 2 O /ha alone and in combination with various organic materials viz., wheat straw and rice straw 3 tons/hs, starch 500 kg/ha and EDTA 250 kg/ha was studied on rice in an alluvial soil. The residual effect was studied on wheat using 32 P as a tracer. The results showed that in the first crop(rice) bonemeal organic matter combination had a significant effect both on dry matter yield and nutrient uptake. In the second crop (wheat) except chemically processed honemeal in combination with EDTA, all other combinations showed a marked positive effect on yield, total P-uptake and 'A' values. Comparison of P-uptake from soil and fertilizer indicated that there was a marked residual effect on the subsequent wheat crop. (author)

Isotope technology as applied to studies of soil fertility, nutrient availability and fertilizer use on flooded rice soils

International Nuclear Information System (INIS)

Patnaik, S.; Mohanty, S.K.; Dash, R.N.

1979-01-01

Research is reviewed on soil fertility and nutrient availability in relation to fertilizer efficiency, especially o stimulated the mineralization of soil N. Losses of added N from oxidation, leaching, denitrification and volatilization could be minimized through placement of N fertilizer in the reduced zone or by the addition of rice straw for rapid immobilization of added N. Fe-P and, to some extent, Al-P provided P to the rice plants, particularly in P-deficient soils. Added phosphates were converted to these forms which, under waterlogged soil conditions, released more P into the soil solution through reductive solubilization of Fe-P and hydrolytic dissolution of Al-P. The rice plants generally absorbed fertilizer N during the vegetative growth period and N mineralized from soil organic matter during the reproductive growth period. 15 N studies indicated higher grain yield and utilization of applied N through fractional application of 70-80% during the vegetative growth period, and the remaining 20-30% top-dressed at the panicle initiation stage. Ammonia-containing and -forming (urea) fertilizers were superior to the nitrate form of N. In field tests, however, the crop recovery of applied N was relatively low. Phosphatic fertilizers were best applied at puddling. In general, water-soluble phosphates were superior to citrate-soluble or insoluble phosphates. The latter could be made as efficient as the water-soluble phosphate, at comparable low rates, by applying to the moist aerobic acid soil 2-3 weeks before flooding and transplanting rice. Tracer studies have been used to evaluate the nutrient-supplying capacity of the soil from the 'A' value concept. 'A' values varied with varying conditions of soil, rate, time and form of fertilizer application. Zn nutrition of the rice plant and fertilizer use with 65 Zn have been studied relatively little. Some lines of future work are suggested

The use of in vitro gas production technique to evaluate molasses supplementation to mulberry (morus alba and rice straw mixed diets

Directory of Open Access Journals (Sweden)

Dwi Yulistiani

2007-12-01

Full Text Available Mulberry foliages have high nutritive value (protein content, digestibility and degradability, therefore it is potential to be used as a supplement to poor quality roughages. The objective of this experiment was to evaluate the effect of addition of fermentable energy in the mixed of mulberry and rice straw basal diet. A control diet consisted of either rice straw (RS or urea treated rice straw mixed with mulberry foliage (URS with ratio of 60 : 40%. Treatment was formulated by supplementation of control diet with molasses (as sources of fermentable energy at 3 levels (5, 10 and 15%. The study was conducted in a 2 x 4 factorial experiment, consisted of 2 levels rice straw (untreated and urea treated and 4 levels molasses supplementation (control and 3 levels for molasses. Diets were evaluated using in vitro gas production. The fermentation kinetics was determined from the incubation of 200 mg sample during 96 hours. The calculation of the kinetics based on exponential equation P = A+ B (1-e-ct. A shorter gas production test was carried out to determine truly degradable fermented substrates (in vitro true organic matter degradability/IVTOMD by incubating 500 mg of samples 24 hours. The result showed that there was no significant interaction between rice straw treatment and molasses supplementation on fermentation characteristics, in vitro true dry matter digestibility, fermented substrate and total volatile fatty acid (VFA production. However there was a significant interaction between rice straw treatment on partitioning factor (PF, gas produced, propionic acid production and ratio between acetic acid and propionic acid. Molasses supplementation significantly (P<0.05 decreased gas production and ratio of acetic to propionic acid, and increase PF, propionic acid production in untreated rice straw mulberry (RSM basal diet. It is concluded that molasses supplementation to RSM diet decreased gas production and ratio of C2/C3, and increased PF and

Chemical characterization and oxidative potential of particles emitted from open burning of cereal straws and rice husk under flaming and smoldering conditions

Science.gov (United States)

Fushimi, Akihiro; Saitoh, Katsumi; Hayashi, Kentaro; Ono, Keisuke; Fujitani, Yuji; Villalobos, Ana M.; Shelton, Brandon R.; Takami, Akinori; Tanabe, Kiyoshi; Schauer, James J.

2017-08-01

Open burning of crop residue is a major source of atmospheric fine particle emissions. We burned crop residues (rice straws, barley straws, wheat straws, and rice husks produced in Japan) in an outdoor chamber and measured particle mass, composition (elemental carbon: EC, organic carbon: OC, ions, elements, and organic species), and oxidative potential in the exhausts. The fine particulate emission factors from the literature were within the range of our values for rice straws but were 1.4-1.9 and 0.34-0.44 times higher than our measured values for barley straw and wheat straw, respectively. For rice husks and wheat straws, which typically lead to combustion conditions that are relatively mild, the EC content of the particles was less than 5%. Levoglucosan seems more suitable as a biomass burning marker than K+, since levoglucosan/OC ratios were more stable than K+/particulate mass ratios among crop species. Stigmasterol and β-sitosterol could also be used as markers of biomass burning with levoglucosan or instead of levoglucosan. Correlation analysis between chemical composition and combustion condition suggests that hot or flaming combustions enhance EC, K+, Cl- and polycyclic aromatic hydrocarbons emissions, while low-temperature or smoldering combustions enhance levoglucosan and water-soluble organic carbon emissions. Oxidative potential, measured with macrophage-based reactive oxygen species (ROS) assay and dithiothreitol (DTT) assay, of open burning fine particles per particulate mass as well as fine particulate emission factors were the highest for wheat straws and second highest for rice husks and rice straws. Oxidative potential per particulate mass was in the lower range of vehicle exhaust and atmosphere. These results suggest that the contribution of open burning is relatively small to the oxidative potential of atmospheric particles. In addition, oxidative potential (both ROS and DTT activities) correlated well with water-insoluble organic species

Microbial Protein Production and Nitrogen Balance of Local Steer Fed Ammoniated Rice Straws Added

Directory of Open Access Journals (Sweden)

H Hindratiningrum

2009-05-01

Full Text Available The objective of the experiment was to investigate the kind of energy source feedstuffs on nutrient balance and microbial protein synthesis in local male beef cattle fed with ammoniated rice straws Twenty steers Peranakan Ongole (PO with average age 1-2 years old were used. They were divided 5 groups based on initial body weight as block. Therefore, Completely Randomised Block Design (CBRD was used for this experiment. Data were analysed by analysis variance and continued honestly significant different (HSD to test the differences between means. The result showed that the range MCP and eficiency MCP were 154,61 g/d until 226,54 g/d and 54,08 gMCP/kg DOMR until 62,64 gMCP/kg DOMR. The range of nitrogen balance were 72,28 gram until 111,67 gram. MCP and efficiency MCP were not affected (P>0,05 by the treatments but balance of nitrogen was affected (P<0,05. Diet containing fresh cassava waste as energy source (R2 was lower (P<0,05 than R1 and R4 while between R1,R3 and R4 was similar. This results indicate that feed source of energy (rice brand, wet cassava waste, dry cassava waste and corn can be used in steers with rice straw ensilage as forage. (Animal Production 11(2: 116-121 (2009 Key Words : Microbial protein production, nitrogen balance, rice straw, ensilage

Different organic loading rates on the biogas production during the anaerobic digestion of rice straw: A pilot study.

Science.gov (United States)

Zhou, Jun; Yang, Jun; Yu, Qing; Yong, Xiaoyu; Xie, Xinxin; Zhang, Lijuan; Wei, Ping; Jia, Honghua

2017-11-01

The aim of this work was to investigate the mesophilic methane fermentation of rice straw at different organic loading rates (OLRs) in a 300m 3 bioreactor. It was found that biogas production increased when the OLR was below 2.00kg VS substrate /(m 3 ·d). The average volumetric biogas production reached 0.86m 3 /(m 3 ·d) at an OLR of 2.00kg VS substrate /(m 3 ·d). Biogas production rate was 323m 3 /t dry rice straw over the whole process. The pH, chemical oxygen demand, volatile fatty acid, and NH 4 + -N concentrations were all in optimal range at different OLRs. High-throughput sequencing analysis indicated that Firmicutes, Fibrobacteres, and Spirochaetes predominated in straw samples. Chloroflexi, Proteobacteria, and Planctomycetes were more abundant in the slurry. The hydrogenotrophic pathway was the main biochemical pathway of methanogenesis in the reactor. This study provides new information regarding the OLR and the differences in the spatial distribution of specific microbiota in a rice straw biogas plant. Copyright © 2017 Elsevier Ltd. All rights reserved.

Degradation of Tetracyclines in Pig Manure by Composting with Rice Straw

Science.gov (United States)

Chai, Rushan; Huang, Lidong; Li, Lingling; Gielen, Gerty; Wang, Hailong; Zhang, Yongsong

2016-01-01

A holistic approach was followed for utilizing tetracyclines (TCs)-contaminated pig manure, by composting this with rice straw in a greenhouse for CO2 fertilization and composted residue application. After composting, the composted residues can be applied to cropland as a supplemental source of synthetic fertilizers. The objective of this study was to determine the effect of pig manure-rice straw composting on the degradation of TCs in pig manure. The results showed that greenhouse composting significantly accelerated the degradation of TCs. Contents (150 mg·kg−1) of oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC) in the composting feedstock could be completely removed within 42 days for OTC and TC, and 14 days for CTC. However, in the control samples incubated at 25 °C in the dark, concentrations of OTC, TC and CTC only decreased 64.7%, 66.7% and 73.3%, respectively, after 49 days. The degradation rates of TCs in the composting feedstock were in the order of CTC > TC > OTC. During the composting process, CTC dissipated rapidly with the time required for 50% degradation (DT50) and 90% degradation (DT90) of 2.4 and 7.9 days, but OTC was more persistent with DT50 and DT90 values of 5.5 and 18.4 days. On the basis of the results obtained in this study, it could be concluded that pig manure-rice straw composting in a greenhouse can help to accelerate the degradation of TCs in pig manure and make composted residues safer for field application. This technology could be an acceptable practice for greenhouse farmers to utilize TCs-contaminated pig manure. PMID:26927136

Impact of industrial effluent on growth and yield of rice (Oryza sativa L.) in silty clay loam soil.

Science.gov (United States)

Anwar Hossain, Mohammad; Rahman, Golum Kibria Muhammad Mustafizur; Rahman, Mohammad Mizanur; Molla, Abul Hossain; Mostafizur Rahman, Mohammad; Khabir Uddin, Mohammad

2015-04-01

Degradation of soil and water from discharge of untreated industrial effluent is alarming in Bangladesh. Therefore, buildup of heavy metals in soil from contaminated effluent, their entry into the food chain and effects on rice yield were quantified in a pot experiment. The treatments were comprised of 0, 25%, 50%, 75% and 100% industrial effluents applied as irrigation water. Effluents, initial soil, different parts of rice plants and post-harvest pot soil were analyzed for various elements, including heavy metals. Application of elevated levels of effluent contributed to increased heavy metals in pot soils and rice roots due to translocation effects, which were transferred to rice straw and grain. The results indicated that heavy metal toxicity may develop in soil because of contaminated effluent application. Heavy metals are not biodegradable, rather they accumulate in soils, and transfer of these metals from effluent to soil and plant cells was found to reduce the growth and development of rice plants and thereby contributed to lower yield. Moreover, a higher concentration of effluent caused heavy metal toxicity as well as reduction of growth and yield of rice, and in the long run a more aggravated situation may threaten human lives, which emphasizes the obligatory adoption of effluent treatment before its release to the environment, and regular monitoring by government agencies needs to be ensured. Copyright © 2015. Published by Elsevier B.V.

Comparison between solid-state and powder-state alkali pretreatment on saccharification and fermentation for bioethanol production from rice straw.

Science.gov (United States)

Yeasmin, Shabina; Kim, Chul-Hwan; Islam, Shah Md Asraful; Lee, Ji-Young

2016-01-01

The efficacy of different concentrations of NaOH (0.25%, 0.50%, 0.75%, and 1.00%) for the pretreatment of rice straw in solid and powder state in enzymatic saccharification and fermentation for the production of bioethanol was evaluated. A greater amount of biomass was recovered through solid-state pretreatment (3.74 g) from 5 g of rice straw. The highest increase in the volume of rice straw powder as a result of swelling was observed with 1.00% NaOH pretreatment (48.07%), which was statistically identical to 0.75% NaOH pretreatment (32.31%). The surface of rice straw was disrupted by the 0.75% NaOH and 1.00% NaOH pretreated samples as observed using field-emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM). In Fourier-transform infrared (FT-IR) spectra, absorbance of hydroxyl groups at 1,050 cm(-1) due to the OH group of lignin was gradually decreased with the increase of NaOH concentration. The greatest amounts of glucose and ethanol were obtained in 1.00% NaOH solid-state pretreated and powder-state hydrolyzed samples (0.804 g g(-1) and 0.379 g g(-1), respectively), which was statistically similar to the use of 0.75% NaOH (0.763 g g(-1) and 0.358 g g(-1), respectively). Thus, solid-state pretreatment with 0.75% NaOH and powder-state hydrolysis appear to be suitable for fermentation and bioethanol production from rice straw.

Trichoderma Reesei single cell protein production from rice straw pulp in solid state fermentation

Science.gov (United States)

Zaki, M.; Said, S. D.

2018-04-01

The dependency on fish meal as a major protein source for animal feed can lead toit priceinstability in line with the increasing in meat production and consumption in Indonesia. In order todeal with this problem, an effort to produce an alternative protein sources production is needed. This scenario is possible due to the abundantavailability of agricultural residues such as rice straw whichcould be utilized as substrate for production of single cell proteins as an alternative proteinsource. This work investigated the potential utilization of rice straw pulp and urea mixture as substrate for the production of local Trichoderma reesei single cell protein in solid state fermentation system. Some parameters have been analyzed to evaluate the effect of ratio of rice straw pulp to urea on mixed single cell protein biomass (mixed SCP biomass) composition, such as total crude protein (analyzed by kjedhal method) and lignin content (TAPPI method).The results showed that crude protein content in mixed SCP biomassincreases with the increasing in fermentation time, otherwise it decreases with the increasing insubstrate carbon to nitrogen (C/N) ratio. Residual lignin content in mixed SCP biomass decreases from 7% to 0.63% during fermentationproceeded of 21 days. The highest crude protein content in mixed SCP biomasswas obtained at substrate C/N ratio 20:1 of 25%.

In Situ Biodiesel Production from Fast-Growing and High Oil Content Chlorella pyrenoidosa in Rice Straw Hydrolysate

Science.gov (United States)

Li, Penglin; Miao, Xiaoling; Li, Rongxiu; Zhong, Jianjiang

2011-01-01

Rice straw hydrolysate was used as lignocellulose-based carbon source for Chlorella pyrenoidosa cultivation and the feasibility of in situ biodiesel production was investigated. 13.7 g/L sugar was obtained by enzymatic hydrolyzation of rice straw. Chlorella pyrenoidosa showed a rapid growth in the rice straw hydrolysate medium, the maximum biomass concentration of 2.83 g/L was obtained in only 48 hours. The lipid content of the cells reached as high as 56.3%. In situ transesterification was performed for biodiesel production. The optimized condition was 1 g algal powder, 6 mL n-hexane, and 4 mL methanol with 0.5 M sulfuric acid at the temperature of 90°C in 2-hour reaction time, under which over 99% methyl ester content and about 95% biodiesel yield were obtained. The results suggested that the method has great potential in the production of biofuels with lignocellulose as an alternative carbon source for microalgae cultivation. PMID:21318171

Efficient dark fermentative hydrogen production from enzyme hydrolyzed rice straw by Clostridium pasteurianum (MTCC116).

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Srivastava, Neha; Srivastava, Manish; Kushwaha, Deepika; Gupta, Vijai Kumar; Manikanta, Ambepu; Ramteke, P W; Mishra, P K

2017-08-01

In the present work, production of hydrogen via dark fermentation has been carried out using the hydrolyzed rice straw and Clostridium pasteurianum (MTCC116). The hydrolysis reaction of 1.0% alkali pretreated rice straw was performed at 70°C and 10% substrate loading via Fe 3 O 4 /Alginate nanocomposite (Fe 3 O 4 /Alginate NCs) treated thermostable crude cellulase enzyme following the previously established method. It is noticed that under the optimized conditions, at 70°C the Fe 3 O 4 /Alginate NCs treated cellulase has produced around 54.18g/L sugars as the rice straw hydrolyzate. Moreover, the efficiency of the process illustrates that using this hydrolyzate, Clostridium pasteurianum (MTCC116) could produce cumulative hydrogen of 2580ml/L in 144h with the maximum production rate of 23.96ml/L/h in 96h. In addition, maximum dry bacterial biomass of 1.02g/L and 1.51g/L was recorded after 96h and 144h, respectively with corresponding initial pH of 6.6 and 3.8, suggesting higher hydrogen production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of straw mulching on soil evaporation during the soil thawing period in a cold region in northeastern China

Science.gov (United States)

Fu, Qiang; Yan, Peiru; Li, Tianxiao; Cui, Song; Peng, Li

2018-04-01

To study the effect of straw mulching on soil water evaporation, it is necessary to measure soil water evaporation under different conditions of straw mulching during the soil thawing period. A field experiment was conducted in winter, and soil evaporation was measured using a microlysimeter on bare land (LD) and 4500 (GF4500), 9000 (GF9000) and 13500 kg/hm2 (GF13500) straw mulch. The influence of different quantities of straw mulch on soil water evaporation during the thawing period was analyzed using the Mallat algorithm, statistical analysis and information cost function. The results showed that straw mulching could delay the thawing of the surface soil by 3-6 d, decrease the speed at which the surface soil thaws by 0.40-0.80 cm/d, delay the peak soil liquid water content, increase the soil liquid water content, reduce the cumulative evaporation by 2.70-7.40 mm in the thawing period, increase the range of soil evaporation by 0.04-0.10 mm in the early stage of the thawing period, and reduce the range of soil evaporation by 0.25-0.90 mm in the late stage of the thawing period. Straw mulching could reduce the range of and variation in soil evaporation and can reduce the effect of random factors on soil evaporation. When the amount of straw mulch exceeded 9000 kg/hm2, the effect of increasing the amount of straw mulch on daily soil water evaporation was small.

Effect of inorganic amendments for in situ stabilization of cadmium in contaminated soils and its phyto-availability to wheat and rice under rotation.

Science.gov (United States)

Rehman, Muhammad Zia-ur; Rizwan, Muhammad; Ghafoor, Abdul; Naeem, Asif; Ali, Shafaqat; Sabir, Muhammad; Qayyum, Muhammad Farooq

2015-11-01

Cadmium (Cd) toxicity is a widespread problem in crops grown on contaminated soils, and little information is available on the role of inorganic amendments in Cd immobilization, uptake, and tolerance in crops especially under filed conditions. The effect of three amendments, monoammonium phosphate (MAP), gypsum, and elemental sulfur (S), on Cd immobilization in soil and uptake in wheat and rice plants, under rotation, were investigated under field conditions receiving raw city effluent since >20 years and contaminated with Cd. Three levels of each treatment, 0.2, 0.4, and 0.8% by weight, were applied at the start of the experiment, and wheat was sown in the field. After wheat harvesting, rice was sown in the same field without application of amendments. Both crops were harvested at physiological maturity, and data regarding grain yield, straw biomass, Cd concentrations, and uptake in grain and straw, and bioavailable Cd in soil and soil pH were recorded. Both MAP and gypsum application increased grain yield and biomass of wheat and rice, while S application did not increase the yield of both crops. MAP and gypsum amendments decreased gain and straw Cd concentrations and uptake in both crops, while S application increased Cd concentrations in these parts which were correlated with soil bioavailable Cd. We conclude that MAP and gypsum amendments could be used to decrease Cd uptake by plants receiving raw city effluents, and gypsum might be a better amendment for in situ immobilization of Cd due to its low cost and frequent availability.

Effect of rice straw silage treated with rumen microbes of buffalo on digestibility and ecosystem of cattle rumen

Directory of Open Access Journals (Sweden)

Thalib A

2000-03-01

Full Text Available Treatment of rice straw silage with addition of buffalo rumen microbes was conducted to improve the ruminal digestion of rice straw in ongole cattle. Three fistulated cattles were each introduced to dietary treatment: I. Untreated rice straw (JPTP, II. Rice straw ensilaged with buffalo rumen microbes (SJPMR-Kr, and ID. Elephant grass (RG. All diets were formulated isonitrogeneous (14% crude protein and fed to animals over a period of 4 weeks. After 4 weeks of feeding trial, rwnen fluid of the animals were evaluated to digest its own basal diet (as substrate. The results show that cumulative gas production resulting from the substrate fermented (96 hours by rumen fluid from cattle fed diet II is 205% of the diet I and 151 % of the diet ID. Measurements of DMD of the substrates after the gas production procedure show the similar trend (ie. DM digestibilities for JPTP= 33%; SJPMR-Kr= 54% dan RG= 45%. Means of in sacco DMD (72 hours incubation confirm the results of gas production (ie. in sacco DM Digestibilities for JPTP= 35%; SJPMR-Kr= 44% and RG= 39%. All results described between treatments are highly significant different (P0.05, except for total VFA (ie. JPTP= 0.52 mg Inri; SJPMR-Kr= 3,37 mg Inri and RG= 3.15 mg Inri.

Bed agglomeration in fluidized combustor fueled by wood and rice straw blends

DEFF Research Database (Denmark)

Thy, Peter; Jenkins, Brian; Williams, R.B.

2010-01-01

Abstract Petrographic techniques have been used to examine bed materials from fluidized bed combustion experiments that utilized wood and rice straw fuel blends. The experiments were conducted using a laboratory-scale combustor with mullite sand beds, firing temperatures of 840 to 1030 °C, and ru...

Bed agglomeration in fluidized combustor fueled by wood and rice straw blends

NARCIS (Netherlands)

Thy, P.; Jenkins, B.M.; Williams, R.B.; Lesher, C.E.; Bakker, R.R.

2010-01-01

Petrographic techniques have been used to examine bed materials from fluidized bed combustion experiments that utilized wood and rice straw fuel blends. The experiments were conducted using a laboratory-scale combustor with mullite sand beds, firing temperatures of 840 to 1030 °C, and run durations

Utilization of agriculture wastes. part I. production of fungal protein from rice and wheat straws

International Nuclear Information System (INIS)

Murtaza, N.; Hussain, S.A.

2000-01-01

Agricultural Agricultural waste of rice and wheat straws were studied for the production of protein and biomass. As these wastes have low protein contents as attempt is made to increase the protein and biomass content of these wastes so as to produce a better product for consumption as food. The studies were conducted using various media and various incubation periods. Some inorganic salts and molasses were added to improve the cultivation of fungi. Aspergillus oryzae produced the results due to its rapid growth which minimized the chance of contamination. Seven days incubation gave the most favourable results in both the agricultural wastes. The maximum production of biomass (33.33%) with a protein value of 20% was obtained with 450 g of rice straw in media no. 2 whereas 400 g of wheat straw on 6 litres of medium produced the best results with 20% biomass and a protein value of 20%. (author)

Growth and Cd uptake by rice (Oryza sativa) in acidic and Cd-contaminated paddy soils amended with steel slag.

Science.gov (United States)

He, Huaidong; Tam, Nora F Y; Yao, Aijun; Qiu, Rongliang; Li, Wai Chin; Ye, Zhihong

2017-12-01

Contamination of rice (Oryza sativa) by Cd is of great concern. Steel slag could be used to amend Cd-contaminated soils and make them safe for cereal production. This work was conducted to study the effects of steel slag on Cd uptake and growth of rice plants in acidic and Cd-contaminated paddy soils and to determine the possible mechanisms behind these effects. Pot (rhizobag) experiments were conducted using rice plants grown on two acidic and Cd-contaminated paddy soils with or without steel slag amendment. Steel slag amendment significantly increased grain yield by 36-45% and root catalase activity, and decreased Cd concentrations in brown rice by 66-77% compared with the control, in both soils. Steel slag amendment also markedly decreased extractable soil Cd, Cd concentrations in pore-water and Cd translocation from roots to above-ground parts. It also significantly increased soil pH, extractable Si and Ca in soils and Ca concentrations in roots. Significant positive correlations were found between extractable soil Cd and Cd concentrations in rice tissues, but it was negatively correlated with soil pH and extractable Si. Calcium in root tissues significantly and negatively correlated with Cd translocation factors from roots to straw. Overall, steel slag amendment not only significantly promoted rice growth but decreased Cd accumulation in brown rice. These benefits appear to be related to improvements in soil conditions (e.g. increasing pH, extractable Si and Ca), a reduction in extractable soil Cd, and suppression of Cd translocation from roots to above-ground parts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Newly isolated Penicillium oxalicum A592-4B secretes enzymes that degrade milled rice straw with high efficiency.

Science.gov (United States)

Aoyama, Akihisa; Kurane, Ryuichiro; Matsuura, Akira; Nagai, Kazuo

2015-01-01

An enzyme producing micro-organism, which can directly saccharify rice straw that has only been crushed without undergoing the current acid or alkaline pretreatment, was found. From the homology with the ITS, 28S rDNA sequence, the strain named A592-4B was identified as Penicillium oxalicum. Activities of the A592-4B enzymes and commercial enzyme preparations were compared by Novozymes Cellic CTec2 and Genencore GC220. In the present experimental condition, activity of A592-4B enzymes was 2.6 times higher than that of CTec2 for degrading milled rice straw. Furthermore, even when a quarter amount of A592-4B enzyme was applied to the rice straw, the conversion rate was still higher than that by CTec2. By utilizing A592-4B enzymes, improved lignocellulose degradation yields can be achieved without pre-treatment of the substrates; thus, contributing to cost reduction as well as reducing environmental burden.

Utilization of rice straw and different treatments to improve its feed value for ruminants: A review

NARCIS (Netherlands)

Sarnklong, C.; Cone, J.W.; Pellikaan, W.F.; Hendriks, W.H.

2010-01-01

This paper gives an overview of the availability, nutritive quality, and possible strategies to improve the utilization of rice straw as a feed ingredient for ruminants. Approximately 80% of the rice in the world is grown by small-scale farmers in developing countries, including South East Asia. The

Saccharification of rice straw by cellulase from a local Trichoderma harzianum SNRS3 for biobutanol production.

Science.gov (United States)

Rahnama, Nooshin; Foo, Hooi Ling; Abdul Rahman, Nor Aini; Ariff, Arbakariya; Md Shah, Umi Kalsom

2014-12-12

Rice straw has shown to be a promising agricultural by-product in the bioconversion of biomass to value-added products. Hydrolysis of cellulose, a main constituent of lignocellulosic biomass, is a requirement for fermentable sugar production and its subsequent bioconversion to biofuels such as biobutanol. The high cost of commercial enzymes is a major impediment to the industrial application of cellulases. Therefore, the use of local microbial enzymes has been suggested. Trichoderma harzianum strains are potential CMCase and β-glucosidase producers. However, few researches have been reported on cellulase production by T. harzianum and the subsequent use of the crude cellulase for cellulose enzymatic hydrolysis. For cellulose hydrolysis to be efficiently performed, the presence of the whole set of cellulase components including exoglucanase, endoglucanase, and β-glucosidase at a considerable concentration is required. Biomass recalcitrance is also a bottleneck in the bioconversion of agricultural residues to value-added products. An effective pretreatment could be of central significance in the bioconversion of biomass to biofuels. Rice straw pretreated using various concentrations of NaOH was subjected to enzymatic hydrolysis. The saccharification of rice straw pretreated with 2% (w/v) NaOH using crude cellulase from local T. harzianum SNRS3 resulted in the production of 29.87 g/L reducing sugar and a yield of 0.6 g/g substrate. The use of rice straw hydrolysate as carbon source for biobutanol fermentation by Clostridium acetobutylicum ATCC 824 resulted in an ABE yield, ABE productivity, and biobutanol yield of 0.27 g/g glucose, 0.04 g/L/h and 0.16 g/g glucose, respectively. As a potential β-glucosidase producer, T. harzianum SNRS3 used in this study was able to produce β-glucosidase at the activity of 173.71 U/g substrate. However, for cellulose hydrolysis to be efficient, Filter Paper Activity at a considerable concentration is also required to initiate the

Discovery of Microorganisms and Enzymes Involved in High-Solids Decomposition of Rice Straw Using Metagenomic Analyses

Science.gov (United States)

D’haeseleer, Patrik; Khudyakov, Jane; Burd, Helcio; Hadi, Masood; Simmons, Blake A.; Singer, Steven W.; Thelen, Michael P.; VanderGheynst, Jean S.

2013-01-01

High-solids incubations were performed to enrich for microbial communities and enzymes that decompose rice straw under mesophilic (35°C) and thermophilic (55°C) conditions. Thermophilic enrichments yielded a community that was 7.5 times more metabolically active on rice straw than mesophilic enrichments. Extracted xylanase and endoglucanse activities were also 2.6 and 13.4 times greater, respectively, for thermophilic enrichments. Metagenome sequencing was performed on enriched communities to determine community composition and mine for genes encoding lignocellulolytic enzymes. Proteobacteria were found to dominate the mesophilic community while Actinobacteria were most abundant in the thermophilic community. Analysis of protein family representation in each metagenome indicated that cellobiohydrolases containing carbohydrate binding module 2 (CBM2) were significantly overrepresented in the thermophilic community. Micromonospora, a member of Actinobacteria, primarily housed these genes in the thermophilic community. In light of these findings, Micromonospora and other closely related Actinobacteria genera appear to be promising sources of thermophilic lignocellulolytic enzymes for rice straw deconstruction under high-solids conditions. Furthermore, these discoveries warrant future research to determine if exoglucanases with CBM2 represent thermostable enzymes tolerant to the process conditions expected to be encountered during industrial biofuel production. PMID:24205054

Discovery of microorganisms and enzymes involved in high-solids decomposition of rice straw using metagenomic analyses.

Directory of Open Access Journals (Sweden)

Amitha P Reddy

Full Text Available High-solids incubations were performed to enrich for microbial communities and enzymes that decompose rice straw under mesophilic (35°C and thermophilic (55°C conditions. Thermophilic enrichments yielded a community that was 7.5 times more metabolically active on rice straw than mesophilic enrichments. Extracted xylanase and endoglucanse activities were also 2.6 and 13.4 times greater, respectively, for thermophilic enrichments. Metagenome sequencing was performed on enriched communities to determine community composition and mine for genes encoding lignocellulolytic enzymes. Proteobacteria were found to dominate the mesophilic community while Actinobacteria were most abundant in the thermophilic community. Analysis of protein family representation in each metagenome indicated that cellobiohydrolases containing carbohydrate binding module 2 (CBM2 were significantly overrepresented in the thermophilic community. Micromonospora, a member of Actinobacteria, primarily housed these genes in the thermophilic community. In light of these findings, Micromonospora and other closely related Actinobacteria genera appear to be promising sources of thermophilic lignocellulolytic enzymes for rice straw deconstruction under high-solids conditions. Furthermore, these discoveries warrant future research to determine if exoglucanases with CBM2 represent thermostable enzymes tolerant to the process conditions expected to be encountered during industrial biofuel production.

Structural elucidation and antioxidant activity of lignin isolated from rice straw and alkali‑oxygen black liquor.

Science.gov (United States)

Jiang, Bo; Zhang, Yu; Gu, Lihui; Wu, Wenjuan; Zhao, Huifang; Jin, Yongcan

2018-05-17

Alkali‑oxygen cooking of lignocellulose offers lignin many structural properties and bioactivities for biorefinery. In this work, milled wood lignin (MWL) and alkali‑oxygen lignin (AOL) were isolated from rice straw and alkali‑oxygen black liquor, respectively. The lignin structure was characterized by spectroscopy and wet chemistry. Antioxidant activity of lignins was assessed by DPPH·and ABTS scavenging ability assay. Results showed the oxidization and condensation of lignin occurred during alkali‑oxygen cooking. The p-hydroxyphenyl was more easily removed from rice straw than guaiacyl and syringyl units. The ester or ether linkages derived from hydroxycynnamic acids, and the main interunit linkages, i.e. β-O-4' bonds, were mostly cleaved. Lignin-xylan complex had high reactivity under alkali‑oxygen condition. Tricin, incorporated into lignin, was detected in MWL but was absent in AOL. Nitrobenzene oxidation showed MWL can well represent the protolignin of rice straw, and the products yield decreased dramatically after alkali‑oxygen cooking. AOL had higher radical scavenging ability than MWL indicating alkali‑oxygen cooking was an effective pathway for the enhancement of antioxidant activity of lignin. Copyright © 2018 Elsevier B.V. All rights reserved.

Rice production in relation to soil quality under different rice-based cropping systems

Science.gov (United States)

Tran Ba, Linh; Sleutel, Steven; Nguyen Van, Qui; Thi, Guong Vo; Le Van, Khoa; Cornelis, Wim

2016-04-01

Soil quality of shallow paddy soils may be improved by introducing upland crops and thus a more diverse crop cultivation pattern. Yet, the causal relationship between crop performance and enhanced soil traits in rice-upland crop rotations remains elusive. The objectives of this study were to (i) find correlations among soil properties under different rice-upland crop systems and link selected soil properties to rice growth and yield, (ii) present appropriate values of soil parameters for sustainable rice productivity in heavy clay soil, (iii) evaluate the effect of rotating rice with upland crops on rice yield and economic benefit in a long-term experiment. A rice-upland crop rotational field experiment in the Vietnamese Mekong delta was conducted for 10 years using a randomized complete block design with four treatments and four replications. Treatments were: (i) rice-rice-rice (control - conventional system as farmers' practice), (ii) rice-maize-rice, (iii) rice-mung bean-rice, and (iv) rice-mung bean-maize. Soil and plant sampling were performed after harvest of the rice crop at the end of the final winter-spring cropping season (i.e. year 10). Results show differences in rice growth and yield, and economic benefit as an effect of the crop rotation system. These differences were linked with changes in bulk density, soil porosity, soil aggregate stability index, soil penetration resistance, soil macro-porosity, soil organic carbon, acid hydrolysable soil C and soil nutrient elements, especially at soil depth of 20-30 cm. This is evidenced by the strong correlation (P < 0.01) between rice plant parameters, rice yield and soil properties such as bulk density, porosity, penetration resistance, soil organic carbon and Chydrolysable. It turned out that good rice root growth and rice yield corresponded to bulk density values lower than 1.3 Mg m-3, soil porosity higher than 50%, penetration resistance below 1.0 MPa, and soil organic carbon above 25 g kg-1. The optimal

Amount, availability, and potential use of rice straw (agricultural residue) biomass as an energy resource in Japan

International Nuclear Information System (INIS)

Matsumura, Yukihiko; Minowa, Tomoaki; Yamamoto, Hiromi

2005-01-01

This paper discusses the use of agricultural residue in Japan as an energy resource, based on the amounts produced and availability. The main agricultural residues in Japan are rice straw and rice husk. Based on a scenario wherein these residues are collected as is the rice product, we evaluate the size, cost, and CO 2 emission for power generation. Rice residue has a production potential of 12 Mt-dry year -1 , and 1.7 kt of rice straw is collected for each storage location. As this is too small an amount even for the smallest scale of power plant available, 2-month operation per year is assumed. Assuming a steam boiler and turbine with an efficiency of 7%, power generation from rice straw biomass can supply 3.8 billion(kW)h of electricity per year, or 0.47% of the total electricity demand in Japan. The electricity generated from this source costs as much as 25 JPY (kW h) -1 (0.21 US$ (kW h) -1 , 1 US$=120 JPY), more than double the current price of electricity. With heat recovery at 80% efficiency, the simultaneous heat supplied via cogeneration reaches 10% of that supplied by heavy oil in Japan. Further cost incentives will be required if the rice residue utilization is to be introduced. It will also be important to develop effective technologies to achieve high efficiency even in small-scale processes. If Japanese technologies enable the effective use of agricultural residue abroad as a result of Japanese effort from the years after 2010, the resulting reduction of greenhouse gas emission can be counted under the framework of the Kyoto Protocol

[Effects of long-term fertilization on soil organic carbon pool and carbon sequestration under double rice cropping].

Science.gov (United States)

Sun, Yu-Tao; Liao, Yu-Lin; Zheng, Sheng-Xian; Nie, Jun; Lu, Yan-Hong; Xie, Jian

2013-03-01

This paper studied the effects of 30 years (1981-2010) fertilization with chemical N, P, and K, pig manure (PM), and rice straw (RS) on the soil organic carbon (SOC) and its components contents under intensive double rice cropping. The experiment was established on a typic Hapli-Stagnic Anthrosols in Hunan in 1981, and the soil samples were collected in November 2010. In treatment NPK, the contents of SOC, particulate organic C (POC), and KMnO4-oxidizable C (KMnO4-C) were higher than those in treatments NP and NK. The combined application of chemical and organic fertilizers (treatments NK+PM, NP+RS, and NPK+RS) made the contents of SOC, POC, and KMnO4-C have a significant increase, as compared with chemical fertilizations. Treatment NK+PM had the highest contents of SOC (84.71 t C.hm-2), POC (8.94 t C.hm-2), and KMnO4-C (21.09 t C.hm-2) in top soil (0-45 cm), followed by treatment NPK+RS. Treatment NK+PM had the highest C sequestration (485 kg C.hm-2.a-1) , followed by treatment NPK+RS (375 kg C.hm-2.a-1). The C sequestration efficiency (CSE) of SOC in the treatments of chemical fertilizers plus pig manure or rice straw was obviously higher than that in the treatments of chemical fertilizations, and the CSE of the POC in fertilization treatments (ranging from 0.4% and 1.2%) was lower than that of the KMnO4-C (ranging from 3.0% to 8.3%). By using the values of humification constant (h) and the decay constant (k) in Jenkinson' s equation, it was possible to predict the SOC storages in different treatments in the year 2010; and by using Jenkinson' s equation, it was possible to calculate the C input required to maintain the SOC storages in the year 1981 (AE). The increase of the SOC in treatments NK+PM, NP+RS, and NPK+RS was due to the annual C input being higher than the AE. It was considered that in the double rice cropping areas in subtropical region of China, long-term application of chemical fertilizers combined with pig manure or rice straw could promote the

Characterization of 140 Japanese and world rice collections cultivated in Nihonmatsu-city in Fukushima in terms of radiocesium activity concentrations in seed grains and straws to explore rice cultivars with low radiocesium accumulation

International Nuclear Information System (INIS)

Katsuhiro Kojima; Djedidi Salem

2017-01-01

We studied varietal difference in radiocesium accumulation by using Japanese and World rice collection for future development of low accumulation varieties. As a result, the radiocesium activity concentration varied by 12- and 22-fold in seed grains and straws, respectively. When we examined the seed grain to straw ratio of radiocesium activity concentration, paddy rice cultivars of Japonica sub-species showed a lower result than Indica and Javanica paddy rice cultivars. These observations suggest that the Japonica paddy rice cultivars may have the property of repressing radioactive cesium translocation to edible parts. (author)

A techno-economic and environmental evaluation of the life cycle of bioethanol produced from rice straw by RT-CaCCO process

International Nuclear Information System (INIS)

Roy, Poritosh; Tokuyasu, Ken; Orikasa, Takahiro; Nakamura, Nobutaka; Shiina, Takeo

2012-01-01

Japan has set an ambitious goal to produce bioethanol from abundant biomass in views to offset some of her greenhouse gas (GHG) emissions. This study attempts to evaluate the life cycle of bioethanol produced from the most common variety of rice straw in Japan (cv. Koshihikari) by enzymatic hydrolysis. Three scenarios are established in the evaluation process. The net energy consumption, CO 2 emission and production costs are estimated to determine if environmentally friendly and economically viable bioethanol can be produced from rice straw in Japan. The net energy consumption, CO 2 emission and production costs are estimated to be 10.43–11.56 GJ/m 3 , 1106.34–1144.94 kg/L and 88.54–137.55 k¥/m 3 (1 US$≈100¥), respectively depending on the scenarios of this study. This study reveals that despite a bit of environmental benefits, the economic viability is doubtful unless innovative technologies along with the renewable energy policy and stakeholders participation are considered. A shift in scenarios not only reduces the production cost, but may also minimize the risk of soil degradation and productivity loss and encourage more stakeholder participation and investment in the bioethanol industry in Japan. -- Highlights: ► Three scenarios are considered to evaluate the life cycle of bioethanol produced from rice straw. ► The net energy consumption, CO 2 emission and production cost are estimated. ► The net energy consumption, CO 2 emission and production cost are dependent on the scenarios. ► A shift in scenarios reduces the emission and production cost of bioethanol.

[Effect of straw-returning on the storage and distribution of different active fractions of soil organic carbon].

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Wang, Hul; Wang, Xu-dong; Tian, Xiao-hong

2014-12-01

The impacts of straw mulching and returning on the storage of soil dissolved organic carbon (DOC), particulate organic carbon (POC) and mineral associated organic carbon (MOC), and their proportions to the total organic carbon (TOC) were studied based on a field experiment. The results showed that compared to the treatment of wheat straw soil-returning (WR), the storage of TOC and MOC decreased by 4.1% and 9.7% respectively in 0-20 cm soil in the treatment with wheat straw mulching (WM), but the storage of DOC and POC increased by 207.7% and 11.9%, and TOC and POC increased significantly in 20-40 cm soil. Compared to the treatment with maize straw soil-returning (MR), the storage of TOC and MOC in the plough pan soil of the treatment with maize straw mulching (MM) increased by 13.6% and 14.6% , respectively. Compared to the WR-MR treatment, the storage of TOC and MOC in top soil (0-20 icm) significantly decreased by 8.5% and 10.3% respectively in WM-MM treatment. The storage of TOC, and POC in top soil was significantly higher in the treatments with maize straw soil-returning or mulching than that with wheat straw. Compared to the treatment without straw (CK), the storage of TOC in top soil increased by 5.2% to 18.0% in the treatments with straw returning or mulching in the six modes (WM, WR, MM, MR, WM-MM,WR-MR) (Porganic carbon fraction in soil, straw soil-returning had the potential to accumulate stable organic carbon fraction. Considering organic carbon sequestration in cropland in the region of Guanzhong plain, maize straw mulching or soil-returning was better than wheat straw, and wheat straw and maize straw soil-returning (WR-MR) were better than wheat and maize straw mulching (WM-MM).

Influence of sulfur on the accumulation of mercury in rice plant (Oryza sativa L.) growing in mercury contaminated soils.

Science.gov (United States)

Li, Yunyun; Zhao, Jiating; Guo, Jingxia; Liu, Mengjiao; Xu, Qinlei; Li, Hong; Li, Yu-Feng; Zheng, Lei; Zhang, Zhiyong; Gao, Yuxi

2017-09-01

Sulfur (S) is an essential element for plant growth and its biogeochemical cycling is strongly linked to the species of heavy metals in soil. In this work, the effects of S (sulfate and elemental sulfur) treatment on the accumulation, distribution and chemical forms of Hg in rice growing in Hg contaminated soil were investigated. It was found that S could promote the formation of iron plaque on the root surface and decrease total mercury (T-Hg) and methylmercury (MeHg) accumulation in rice grains, straw, and roots. Hg in the root was dominated in the form of RS-Hg-SR. Sulfate treatment increased the percentage of RS-Hg-SR to T-Hg in the rice root and changed the Hg species in soil. The dominant Hg species (70%) in soil was organic substance bound fractions. Sulfur treatment decreased Hg motility in the rhizosphere soils by promoting the conversion of RS-Hg-SR to HgS. This study is significant since it suggests that low dose sulfur treatment in Hg-containing water irrigated soil can decrease both T-Hg and MeHg accumulation in rice via inactivating Hg in the soil and promoting the formation of iron plaque in rice root, which may reduce health risk for people consuming those crops. Copyright © 2017. Published by Elsevier Ltd.

Effects of Straw Return in Deep Soils with Urea Addition on the Soil Organic Carbon Fractions in a Semi-Arid Temperate Cornfield.

Science.gov (United States)

Zou, Hongtao; Ye, Xuhong; Li, Jiaqi; Lu, Jia; Fan, Qingfeng; Yu, Na; Zhang, Yuling; Dang, Xiuli; Zhang, Yulong

2016-01-01

Returning straw to deep soil layers by using a deep-ditching-ridge-ploughing method is an innovative management practice that improves soil quality by increasing the soil organic carbon (SOC) content. However, the optimum quantity of straw return has not been determined. To solve this practical production problem, the following treatments with different amounts of corn straw were investigated: no straw return, CK; 400 kg ha-1 straw, S400; 800 kg ha-1 straw, S800; 1200 kg ha-1 straw, S1200; and 1600 kg ha-1 straw, S1600. After straw was returned to the soil for two years, the microbial biomass C (MBC), easily oxidized organic C (EOC), dissolved organic C (DOC) and light fraction organic C (LFOC) content were measured at three soil depths (0-10, 10-20, and 20-40 cm). The results showed that the combined application of 800 kg ha-1 straw significantly increased the EOC, MBC, and LFOC contents and was a suitable agricultural practice for this region. Moreover, our results demonstrated that returning straw to deep soil layers was effective for increasing the SOC content.

Effects of Straw Incorporation on Soil Nutrients, Enzymes, and Aggregate Stability in Tobacco Fields of China

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Jiguang Zhang

2016-07-01

Full Text Available To determine the effects of straw incorporation on soil nutrients, enzyme activity, and aggregates in tobacco fields, we conducted experiments with different amounts of wheat and maize straw in Zhucheng area of southeast Shandong province for three years (2010–2012. In the final year of experiment (2012, straw incorporation increased soil organic carbon (SOC and related parameters, and improved soil enzyme activity proportionally with the amount of straw added, except for catalase when maize straw was used. And maize straw incorporation was more effective than wheat straw in the tobacco field. The percentage of aggregates >2 mm increased with straw incorporation when measured by either dry or wet sieving. The mean weight diameter (MWD and geometric mean diameter (GMD in straw incorporation treatments were higher than those in the no-straw control (CK. Maize straw increased soil aggregate stability more than wheat straw with the same incorporation amount. Alkaline phosphatase was significantly and negatively correlated with soil pH. Sucrase and urease were both significantly and positively correlated with soil alkali-hydrolysable N. Catalase was significantly but negatively correlated with soil extractable K (EK. The MWD and GMD by dry sieving had significantly positive correlations with SOC, total N, total K, and EK, but only significantly correlated with EK by wet sieving. Therefore, soil nutrients, metabolic enzyme activity, and aggregate stability might be increased by increasing the SOC content through the maize or wheat straw incorporation. Moreover, incorporation of maize straw at 7500 kg·hm−2 was the best choice to enhance soil fertility in the tobacco area of Eastern China.

Study on allelopathic effects of Rice and Wheat Soil-Like Substrate on several plants

Science.gov (United States)

Li, Leyuan; Fu, Wenting; He, Wenting; Liu, Hong

Rice and wheat are the traditional food of Chinese people, and therefore the main crop candidates for bio-regenerative life-support systems. Recycling rice and wheat straw is an important issue concerning the system. In order to decide if the mixed-substrate made of rice and wheat straw is suitable of plant cultivation, Rice and Wheat Soil-Like Substrate was tested in an aqueous extract germination experiment. The effects of different concentrations of aqueous extract on seed vigor, seedling growth and development situations and the physiological and biochemical characteristics of wheat, lettuce and pumpkin were studied, and the presence and degrees of allelopathic effects were analyzed. The test results showed that this type of SLS exerted different degrees of allelopathic effect on wheat and lettuce; this allelopathic effect was related to the concentration of SLS aqueous extract. The most significant phenomenon is that with the increase of aqueous extract concentration, the seed germination, root length and shoot fresh weight of wheat decreased; and every concentration of aqueous extract showed significant inhibition on the root length and root fresh weight of lettuce. However, this type of SLS showed little effect on the growth of pumpkin seedlings. Contents changes of chlorophyll and endogenous hormones in wheat and lettuce seedlings, and the chemical compositions of SLS were measured, and the mechanism of allelopathic effect was preliminarily analyzed.

Relative availability of crop residue-N in rice cultivation

International Nuclear Information System (INIS)

Sirwando, H; Abdullah, N.

1988-01-01

The use of plant residues for soil amendment will reduce the use of chemical fertilizers. The experiment to study the uptake of N from various plant residues by rice crop. Three kinds of plant residue of soybean labelled with 15-N. Four levels of urea (0, 15, 30, 40 kg N/ha) were applied to aluvial soil from Pusakanegara. The factorial experiment was conducted in fully randomize design, with plant residues as the main treatment, and rate of urea as substreatment. The results obtained from this experiment showed that plant dry weight, N content of grain, straw, and the whole plant of Atomita I rice treated with soybean strow seens to be higher than those treated with the straw of rice or corn. (author). 6 refs.; 7 tabs

32P tracer studies on the efficiency of ammonium nitrate phosphates and polyphosphates for growing rice on different soil types

International Nuclear Information System (INIS)

Sadanandan, A.K.; Mohanty, S.K.; Patnaik, S.; Mistry, K.B.

1980-01-01

A pot experiment was conducted with 32 P tagged phosphates to evaluate the efficiency of ammonium nitrate phosphate containing 30, 50 and 70 percent of P in the water soluble form, tri- and tetra-ammonium pyrophosphate, as compared with mono-ammonium ortho-phosphate (MAP) for growing rice on red, laterite and black soils, with regard to recovery of applied P in soil, dry matter production and utilization of applied P by crop at flowering and grain and straw yield at harvest. Ammonium nitrate phosphates containing 50 percent or more of P in the water soluble form could be used for growing rice on all soil types. The pyrophosphates were as efficient as MAP on soils having pH 6.2 and above but less efficient in soils of lower pH. (author)

Toward the complete utilization of rice straw: Methane fermentation and lignin recovery by a combinational process involving mechanical milling, supporting material and nanofiltration.

Science.gov (United States)

Sasaki, Kengo; Okamoto, Mami; Shirai, Tomokazu; Tsuge, Yota; Fujino, Ayami; Sasaki, Daisuke; Morita, Masahiko; Matsuda, Fumio; Kikuchi, Jun; Kondo, Akihiko

2016-09-01

Rice straw was mechanically milled using a process consuming 1.9MJ/kg-biomass, and 10g/L of unmilled or milled rice straw was used as the carbon source for methane fermentation in a digester containing carbon fiber textile as the supporting material. Milling increased methane production from 226 to 419mL/L/day at an organic loading rate of 2180mg-dichromate chemical oxygen demand/L/day, corresponding to 260mLCH4/gVS. Storage of the fermentation effluent at room temperature decreased the weight of the milled rice straw residue from 3.81 to 1.00g/L. The supernatant of the effluent was subjected to nanofiltration. The black concentrates deposited on the nanofiltration membranes contained 53.0-57.9% lignin. Solution nuclear magnetic resonance showed that lignin aromatic components such as p-hydroxyphenyl (H), guaiacyl (G), and syringyl (S) were retained primarily, and major lignin interunit structures such as the β-O-4-H/G unit were absent. This combinational process will aid the complete utilization of rice straw. Copyright © 2016. Published by Elsevier Ltd.

THIOGLYCOLIC ACID ESTERIFIED IN TO RICE STRAW FOR REMOVING LEAD FROM AQUEOUS SOLUTION

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R. Gong

2011-09-01

Full Text Available Thiol rice straw (TRS was prepared by esterifying thioglycolic acid onto rice straw in the medium of acetic anhydride and acetic acid with sulfuric acid as catalyst. The sorption of lead (Pb on TRS from aqueous solution was subsequently investigated. The batch experiments showed that Pb removal was dependent on initial pH, sorbent dose, Pb concentration, contact time, and temperature. The maximum value of Pb removal appeared at pH 5. For 100 mg/L of Pb solution, a removal ratio of greater than 98% could be achieved with 2.0 g/L or more of TRS. The isothermal data of Pb sorption conformed well to the Langmuir model, and the maximum sorption capacity (Qm of TRS for Pb was 104.17 mg/g. The equilibrium of Pb removal was reached within 120 min. The Pb removal process could be described by the pseudo-first-order kinetic model. The thermodynamic study indicated that the Pb removal process was spontaneous and endothermic.

Use of rice straw ash as substitute of feldspar in triaxial porcelain

International Nuclear Information System (INIS)

Alvaro Guzman, A.; Silverio Delvasto, A.; Enrique Sanchez, V.; Vicente Amigo, B.

2013-01-01

The substitution of raw materials for processing high energy consumption materials by agricultural and agro-industrial wastes causes a positive impacts on the environment preservation. One of these residues is rice straw, which according to FAO estimation, its annual production is about 600 million tons. In this research was studied the use of rice straw ash as substitute of the use of feldspar in the white ware production. Clay-feldspar-quartz porcelains are referred to as triaxial white ware. Specimens of semidry triaxial mixtures, where feldspar was substituted for different percentages of CTA, were prepared by uniaxial pressing, followed by drying and sintering. Physical and mechanical properties of sintered bodies were evaluated. The porosity and the compressive strength of the fired pieces do increase with additions of up to 75% of CTA in substitution of feldspar. Their mineralogical phases were determined by DRX and SEM; grains of quartz, and needles of primary and secondary mullite were identified in a vitreous phase. It was concluded that feldspar can be substituted positively by CTA in white ware pastes. (Author) 22 refs.

Effects of screenhouse cultivation and organic materials incorporation on global warming potential in rice fields.

Science.gov (United States)

Xu, Guochun; Liu, Xin; Wang, Qiangsheng; Xiong, Ruiheng; Hang, Yuhao

2017-03-01

Global rice production will be increasingly challenged by providing healthy food for a growing population at minimal environmental cost. In this study, a 2-year field experiment was conducted to investigate the effects of a novel rice cultivation mode (screenhouse cultivation, SHC) and organic material (OM) incorporation (wheat straw and wheat straw-based biogas residue) on methane (CH 4 ) and nitrous oxide (N 2 O) emissions and rice yields. In addition, the environmental factors and soil properties were also determined. Relative to the traditional open-field cultivation (OFC), SHC decreased the CH 4 and N 2 O emissions by 6.58-18.73 and 2.51-21.35%, respectively, and the global warming potential (GWP) was reduced by 6.49-18.65%. This trend was mainly because of lower soil temperature and higher soil redox potential in SHC. Although the rice grain yield for SHC were reduced by 2.51-4.98% compared to the OFC, the CH 4 emissions and GWP per unit of grain yield (yield-scaled CH 4 emissions and GWP) under SHC were declined. Compared to use of inorganic fertilizer only (IN), combining inorganic fertilizer with wheat straw (WS) or wheat straw-based biogas residue (BR) improved rice grain yield by 2.12-4.10 and 4.68-5.89%, respectively. However, OM incorporation enhanced CH 4 emissions and GWP, leading to higher yield-scaled CH 4 emissions and GWP in WS treatment. Due to rice yield that is relatively high, there was no obvious effect of BR treatment on them. These findings suggest that apparent environmental benefit can be realized by applying SHC and fermenting straw aerobically before its incorporation.

Increased microbial functional diversity under long-term organic and integrated fertilization in a paddy soil.

Science.gov (United States)

Ding, Long-Jun; Su, Jian-Qiang; Sun, Guo-Xin; Wu, Jin-Shui; Wei, Wen-Xue

2018-02-01

Microbes play key roles in diverse biogeochemical processes including nutrient cycling. However, responses of soil microbial community and functional genes to long-term integrated fertilization (chemical combined with organic fertilization) remain unclear. Here, we used pyrosequencing and a microarray-based GeoChip to explore the shifts of microbial community and functional genes in a paddy soil which received over 21-year fertilization with various regimes, including control (no fertilizer), rice straw (R), rice straw plus chemical fertilizer nitrogen (NR), N and phosphorus (NPR), NP and potassium (NPKR), and reduced rice straw plus reduced NPK (L-NPKR). Significant shifts of the overall soil bacterial composition only occurred in the NPKR and L-NPKR treatments, with enrichment of certain groups including Bradyrhizobiaceae and Rhodospirillaceae families that benefit higher productivity. All fertilization treatments significantly altered the soil microbial functional structure with increased diversity and abundances of genes for carbon and nitrogen cycling, in which NPKR and L-NPKR exhibited the strongest effect, while R exhibited the least. Functional gene structure and abundance were significantly correlated with corresponding soil enzymatic activities and rice yield, respectively, suggesting that the structural shift of the microbial functional community under fertilization might promote soil nutrient turnover and thereby affect yield. Overall, this study indicates that the combined application of rice straw and balanced chemical fertilizers was more pronounced in shifting the bacterial composition and improving the functional diversity toward higher productivity, providing a microbial point of view on applying a cost-effective integrated fertilization regime with rice straw plus reduced chemical fertilizers for sustainable nutrient management.

Effects of Combination of Rice Straw with Alfalfa Pellet on Milk Productivity and Chewing Activity in Lactating Dairy Cows

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Y. J. Na

2014-07-01

Full Text Available An experiment was conducted to determine the effects of diets containing coarse-texture rice straw and small particle size alfalfa pellets as a part of total mixed ration (TMR on milk productivity and chewing activity in lactating dairy cows. Sixteen multiparous Holstein dairy cows (670±21 kg body weight in mid-lactation (194.1±13.6 days in milk were randomly assigned to TMR containing 50% of timothy hay (TH or TMR containing 20% of rice straw and 30% of alfalfa pellet mixture (RSAP. Geometric mean lengths of TH and RSAP were found to be 5.8 and 3.6, respectively. Dry matter intake, milk yield and milk composition were measured. Moreover, eating and ruminating times were recorded continuously using infrared digital camcorders. Milk yield and milk composition were not detected to have significant differences between TH and RSAP. Dry matter intake (DMI did not significantly differ for cows fed with TH or RSAP. Although particle size of TH was larger than RSAP, eating, ruminating and total chewing time (min/d or min/kg of DMI on TH and RSAP were similar. Taken together, our results suggest that using a proper amount of coarse-texture rice straw with high value nutritive alfalfa pellets may stimulate chewing activity in dairy cows without decreasing milk yield and composition even though the quantity of rice straw was 40% of TH.

The use of straw mulch as a strategy to prevent extreme soil erosion rates in citrus orchard. A Rainfall simulation approach

Science.gov (United States)

Cerdà, Artemi; Giménez-Morera, Antonio; Jordán, Antonio; Pereira, Paulo; Novara, Agata; García-Orenes, Fuensanta

2014-05-01

Not only the Sahel (Haregeweyn et al., 2013), the deforested land (Borelli et al., 2013) the chinese Plateau are affected by intense soil erosion rates (Zhao et al., 2013). Soil erosion affect agriculture land (Cerdà et al., 2009), and citrus orchards are being seeing as one of the crops with the highest erosion rates due to the managements that avoid the catch crops, weeds or litter. Example of the research carried out on citrus orchards is found in the Mediterranean (Cerdà and Jurgensen, 2008; 2009; Cerdà et al., 2009a; 2009b; Cerdà et al., 2011; 2012) and in China (Wu et al., 1997; Xu et al., 2010; Wang et al., 2011; Wu et al., 2011; Liu et al., 2011; Lü et al., 2011; Xu et al., 2012), and they confirm the non sustainable soil losses measured. The land management in citrus plantations results in soil degradation too (Lu et al., 1997; Lü et al., 2012; Xu et al., 2012). The use of cover crops to reduce the soil losses (Lavigne et al., 2012; Le Bellec et al., 2012) and the use of residues such as dried citrus peel has been found successful. There is a need to find new plants or residues to protect the soils on citrus orchards. Agriculture produces a high amount of residues. The pruning can contribute with a valuable source of nutrients and a good soil protection. The leaves of the trees, and some parts of the plants, once harvest can contribute to reduce the soil losses. Due to the mechanization of the agriculture, and the reduction of the draft animals (mainly horses, mules, donkeys and oxen) the straw is being a residue instead of a resource. The Valencia region is the largest producer of citrus in Europe, and the largest exporter in the world. This citrus production region is located in the eastern cost of Spain where we can find the rice production area of the l'Albufera Lagoon paddy fields, the third largest production region in Spain. This means, a rice production region surrounded by the huge citrus production region. There, the rice straw is not used

Adding distiller's grains and molasses on fermentation quality of rice straw silages

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XianJun Yuan

Full Text Available ABSTRACT: Ensilage is a simple and low-cost strategy to enable long term preservation and environmentally friendly utilization of agricultural by-products, such as straws and distiller's grains (DG for ruminants. Effect of mixing different proportions of DG and rice straw (i.e. 0, 10, 20 or 30% of DG with or without 5% molasses addition on fermentation and chemical variables of silages was evaluated. The study was conducted as a randomized blocks design in a 4 × 2 factorial arrangement, with three replications, using laboratory silos of 1L capacity (n=24. Despite a significant interaction (P<0.01 between DG and molasses addition was observed for most variables, in general the increased addition of DG linearly decreased the pH value, acetic acid (AA, butyric acid (BA and ammonia N concentration (P<0.01, and increased the lactic acid (LA concentration (P<0.01. Exception was the propionic acid concentration which linearly decreased without molasses addition and linearly increased with molasses addition at increased proportion of DG (P<0.01. In both silages with or without molasses the addition of DG increased the dry matter, water soluble carbohydrates and crude protein (P<0.01, and decreased the NDF content (P<0.01. Based on the perspective of maximum utilization of rice straw, the mixture of 10% of DG associated to 5% molasses at ensilage process is recommended.

Effects on soil quality of biochar and straw amendment in conjunction with chemical fertilizers

Institute of Scientific and Technical Information of China (English)

HE Li-li; ZHONG Zhe-ke; YANG Hui-min

2017-01-01

The objective of this study was to evaluate the effects on chemical and microbiological properties of paddy soil of short-term biochar,straw,and chemical fertilizers compared with chemical fertilization alone.Five soil fertilization treatments were evaluated:regular chemical fertilizers (RF),straw+regular chemical fertilizers (SRF),straw biochar+regular chemical fertilizers (SCRF),bamboo biochar (BC)+regular chemical fertilizers (BCRF),and straw biochar+70％ regular chemical fertilizers (SC+70％RF).Their effects were investigated after approximately 1.5 years.The soil pH and cation exchange capacity (CEC) were significantly higher in biochar-treated soils.The soil phosphorous (P) and potassium (K) contents increased with biochar application.The soil Colwell P content was significantly increased with the addition of straw biochar in the treatments of SCRF and SC+70％RF.The oxygen (O):carbon (C) ratio doubled in BC picked from the soil.This indicated that BC underwent a significant oxidation process in the soil.The denaturing gradient gel electrophoresis (DGGE) fingerprints of microbial communities differed among the treatments.Soils with added biochar had higher Shannon diversity and species richness indices than soils without biochars.The results suggest that biochar can improve soil fertility.

/sup 32/P tracer studies on the efficiency of ammonium nitrate phosphates and polyphosphates for growing rice on different soil types

Energy Technology Data Exchange (ETDEWEB)

Sadanandan, A K; Mohanty, S K; Patnaik, S [Central Rice Research Inst., Cuttack (India); Mistry, K B [Bhabha Atomic Research Centre, Bombay (India). Biology and Agriculture Div.

1980-12-01

A pot experiment was conducted with /sup 32/P tagged phosphates to evaluate the efficiency of ammonium nitrate phosphate containing 30, 50 and 70 percent of P in the water soluble form, tri- and tetra-ammonium pyrophosphate, as compared with mono-ammonium ortho-phosphate (MAP) for growing rice on red, laterite and black soils, with regard to recovery of applied P in soil, dry matter production and utilization of applied P by crop at flowering and grain and straw yield at harvest. Ammonium nitrate phosphates containing 50 percent or more of P in the water soluble form could be used for growing rice on all soil types. The pyrophosphates were as efficient as MAP on soils having pH 6.2 and above but less efficient in soils of lower pH.

Thermogravimetric analysis of rice and wheat straw catalytic combustion in air- and oxygen-enriched atmospheres

International Nuclear Information System (INIS)

Yu Zhaosheng; Ma Xiaoqian; Liu Ao

2009-01-01

By thermogravimetric analysis (TGA) study, the influences of different catalysts on the ignition and combustion of rice and wheat straw in air- and oxygen-enriched atmospheres have been investigated in this paper. Straw combustion is divided into two stages. One is the emission and combustion of volatiles and the second is the combustion of fixed carbon. The existence of catalysts in the first step enhances the emission of volatiles from the straw. The action of catalysts in the second step of straw combustion may be as a carrier of oxygen to the fixed carbon. Two parameters have been used to compare the characteristics of ignition and combustion of straw under different catalysts and in various oxygen concentrations. One is the temperature when the conversion degree combustible (CDC) of straw is 5%, the other is the CDC when the temperature is 900 deg. C. By comparing the different values of the two parameters, the different influences of the catalysts and oxygen concentration on the ignition and combustion of straw have been studied, the action of these catalysts for straw ignition and combustion in air and oxygen-enriched atmosphere is effective except the oxygen-enriched catalytic combustion of wheat straw fixed carbon

Effects of straw mulching on soil evaporation during the soil thawing ...

Indian Academy of Sciences (India)

26

Keywords: straw mulching, soil water evaporation, soil thawing period, freezing depth, soil liquid water content. 1. Introduction. The Songnen Plain, located in northeastern China, has 594×104 ha of cultivated land area and a grain yield of 395×108 kg. It is one of the most important food production bases in China (Yan et al.

The effect of wheat straw quality on the rate of its mineralisation in soil

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Tatuśko Natalia

2017-06-01

Full Text Available The aim of this study was to assess the effect of straw of two spring wheat cultivars, Tybalt – with the culm filled with pith, and Ostka Smolicka – with the hollow culm, added to light textured soil, on the mineralisation rate of organic matter. The incubation experiment was established under laboratory conditions and comprised three experimental combinations: K1 was soil with an addition of pith-filled culms, K2 – soil with an addition of straw with hollow culms, and K0 – the control with no straw added. In all the combinations, mineral fertilisation was applied in the form of urea. Incubation lasted for 14 months. At specific dates the amounts of CO2 released within 24 h and pH values were recorded. The rate of organic matter mineralisation was expressed in mg CO2·d−1. Analyses showed that the addition of straw, both with pith-filled and hollow culms, significantly influenced the mineralisation of organic matter in the first months of incubation. Mineralisation was most intensive in the soil incubated with straw with hollow culms. The large amount of released carbon dioxide in the first days of incubation caused a decrease in pH both in the control soil and in soils with the addition of straw. The change in the soil reaction to its initial value was recorded at day 222 for the soil combination K0 and at day 250 of incubation in soils fertilised with straw.

[Effects of adding straw carbon source to root knot nematode diseased soil on soil microbial biomass and protozoa abundance].

Science.gov (United States)

Zhang, Si-Hui; Lian, Jian-Hong; Cao, Zhi-Ping; Zhao, Li

2013-06-01

A field experiment with successive planting of tomato was conducted to study the effects of adding different amounts of winter wheat straw (2.08 g x kg(-1), 1N; 4.16 g x kg(-1), 2N; and 8.32 g x kg(-1), 4N) to the soil seriously suffered from root knot nematode disease on the soil microbial biomass and protozoa abundance. Adding straw carbon source had significant effects on the contents of soil microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) and the abundance of soil protozoa, which all decreased in the order of 4N > 2N > 1N > CK. The community structure of soil protozoa also changed significantly under straw addition. In the treatments with straw addition, the average proportion of fagellate, amoeba, and ciliates accounted for 36.0%, 59.5%, and 4.5% of the total protozoa, respectively. Under the same adding amounts of wheat straw, there was an increase in the soil MBC and MBN contents, MBC/MBN ratio, and protozoa abundance with increasing cultivation period.

[Effects of Warming and Straw Application on Soil Respiration and Enzyme Activity in a Winter Wheat Cropland].

Science.gov (United States)

Chen, Shu-tao; Sang, Lin; Zhang, Xu; Hu, Zheng-hua

2016-02-15

In order to investigate the effects of warming and straw application on soil respiration and enzyme activity, a field experiment was performed from November 2014 to May 2015. Four treatments, which were control (CK), warming, straw application, and warming and straw application, were arranged in field. Seasonal variability in soil respiration, soil temperature and soil moisture for different treatments were measured. Urease, invertase, and catalase activities for different treatments were measured at the elongation, booting, and anthesis stages. The results showed that soil respiration in different treatments had similar seasonal variation patterns. Seasonal mean soil respiration rates for the CK, warming, straw application, and warming and straw application treatments were 1.46, 1.96, 1.92, and 2.45 micromol x (m2 x s)(-1), respectively. ANOVA indicated that both warming and straw applications significantly (P soil respiration compared to the control treatment. The relationship between soil respiration and soil temperature in different treatments fitted with the exponential regression function. The exponential regression functions explained 34.3%, 28.1%, 24.6%, and 32.0% variations of soil respiration for CK, warming, straw application, and warming and straw application treatments, respectively. Warming and straw applications significantly (P soil respiration and urease activity fitted with a linear regression function, with the P value of 0.061. The relationship between soil respiration and invertase (P = 0.013), and between soil respiration and catalase activity (P = 0.002) fitted well with linear regression functions.

Cadmium accumulation in and tolerance of rice (Oryza sativa L.) varieties with different rates of radial oxygen loss

International Nuclear Information System (INIS)

Wang, M.Y.; Chen, A.K.; Wong, M.H.; Qiu, R.L.; Cheng, H.; Ye, Z.H.

2011-01-01

Cadmium (Cd) uptake and tolerance were investigated among 20 rice cultivars based on a field experiment (1.2 mg Cd kg -1 in soil) and a soil pot trial (control, 100 mg Cd kg -1 ), and rates of radial oxygen loss (ROL) were measured under a deoxygenated solution. Significant differences were found among the cultivars in: (1) brown rice Cd concentrations (0.11-0.29 mg kg -1 ) in a field soil, (2) grain Cd tolerance (34-113%) and concentrations (2.1-6.5 mg kg -1 ) in a pot trial, and (3) rates of ROL (15-31 mmol O 2 kg -1 root d.w. h -1 ). Target hazard quotients were calculated for the field experiment to assess potential Cd risk. Significant negative relationships were found between rates of ROL and concentrations of Cd in brown rice or straw under field and greenhouse conditions, indicating that rice cultivars with higher rates of ROL had higher capacities for limiting the transfer of Cd to rice and straw. - Highlights: → There are significant differences in brown rice Cd concentrations and rates of ROL among the rice cultivars. → The rates of ROL are significantly correlated with concentrations of Cd in brown rice. → Rice cultivars with higher rates of ROL have higher capacities for limiting the transfer of Cd to rice and straw. - Rice cultivars with high rates of ROL tended to accumulate low Cd in grains.

Effect of Se-enriched Organic Fertilizers on Selenium Accumulation in Corn and Soil

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LI Sheng-nan

2015-12-01

Full Text Available The effect of two Se-enriched organic fertilizers (cow dung and rice straw biochar on selenium accumulation of corn growing in selenium deficient soil was studied with pot experiment. The results showed that corn accumulated more selenium and the selenium was much easier to convert from root to shoot in the corn plant with the application of Se-enriched cow dung than Se-enriched rice straw biochar. With the application of more organic fertilizer such as 25 t·hm-2 Se-enriched cow dung or 40 t·hm-2 Se-enriched rice straw biochar, the accumulation of selenium and growth status of corn were getting better than the other treatments. At the same time, as the application amount of Se-enriched organic fertilizers (cow dung and rice straw biochar increased, the total selenium content in the soil also increased, which positively correlated with each other.

Effect of wheat and Miscanthus straw biochars on soil enzymatic activity, ecotoxicity, and plant yield

Science.gov (United States)

Mierzwa-Hersztek, Monika; Gondek, Krzysztof; Klimkowicz-Pawlas, Agnieszka; Baran, Agnieszka

2017-07-01

The variety of technological conditions and raw materials from which biochar is produced is the reason why its soil application may have different effects on soil properties and plant growth. The aim of this study was to evaluate the effect of the addition of wheat straw and Miscanthus giganteus straw (5 t DM ha-1) and biochar obtained from this materials in doses of 2.25 and 5 t DM ha-1 on soil enzymatic activity, soil ecotoxicity, and plant yield (perennial grass mixture with red clover). The research was carried out under field conditions on soil with the granulometric composition of loamy sand. No significant effect of biochar amendment on soil enzymatic activity was observed. The biochar-amended soil was toxic to Vibrio fischeri and exhibited low toxicity to Heterocypris incongruens. Application of wheat straw biochar and M. giganteus straw biochar in a dose of 5 t DM ha-1 contributed to an increase in plant biomass production by 2 and 14%, respectively, compared to the soil with mineral fertilisation. Biochars had a more adverse effect on soil enzymatic activity and soil ecotoxicity to H. incongruens and V. fischeri than non-converted wheat straw and M. giganteus straw, but significantly increased the grass crop yield.

Optimization of twin gear-based pretreatment of rice straw for bioethanol production

International Nuclear Information System (INIS)

Ahmed, Muhammad Ajaz; Rehman, Muhammd Saif Ur; Terán-Hilares, Ruly; Khalid, Saira; Han, Jong-In

2017-01-01

Highlights: • Twin gear reactor is a continuous high solids pretreatment reactor. • RSM was applied to optimize twin gear pretreatment for enzymatic digestibility. • 89% enzymatic digestibility was achieved under optimum conditions. • Thermomechanical pretreatment altered the structural features of rice straw. - Abstract: A laboratory twin-gear reactor (TGR) was investigated as a new means for the pretreatment of high solid lignocelluloses. Response surface methodology based on Box Behnken Design was used to optimize the enzymatic digestibility with respect to the pretreatment process variables: temperature of 50–90 °C, NaOH concentration of 2–6% and no. of cycles of 30–60. The results revealed that the TGR-based pretreatment led to the significant structural alterations through increases in pore size, pore volume, cellulose crystallinity and surface area. SEM images also confirmed the surface modifications in the pretreated rice straw. A response surface quadratic model predicted 90% of the enzymatic digestibility, and it was confirmed experimentally and through the analysis of variance (ANOVA) as well. The TGR extrusion proved to be an effective means for exceedingly high solids lignocellulose.

Trace the exploitation of Egyptian rice straw through spectral and thermal measurements

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Raafat M. Issa

2016-09-01

Full Text Available Cellulose from rice straw obtained at low sodium hydroxide solution concentration with high quality was used to obtain different cellulose derivatives through xanthation. Cellulose was then treated with carbon disulfide in the presence of sodium hydroxide. The viscose obtained was characterized with both chemical and instrumental analyses, namely, IR spectra, TGA and DTA analysis as well as SEM (scanning electron microscopy.

Dissipation and Residue Level of Thifluzamide in Rice Field Ecosystem

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Weitao Chen

2015-01-01

Full Text Available An efficient modified QuEChERS method combined with high performance liquid chromatography-tandem mass spectrometry detection (HPLC-MS/MS was established and evaluated for the residue analysis of thifluzamide in rice grain, husk, straw, seedling, paddy water, and soil. Thifluzamide residues were extracted with acetonitrile, cleaned up with primary secondary amine (PSA, and then determined by HPLC-MS/MS. The fortified recoveries were 76%–106% with RSDs of 3%–13%. The results of the supervised field trials at two experiment sites showed that thifluzamide dissipated rapidly in paddy fields, and the half-lives in paddy water, soil, and rice seedling were 0.3–0.6 d, 1.8–3.6 d, and 4.3–13.9 d, respectively. At harvest time, when the preharvest interval (PHI was set as 21 d, the final residues of thifluzamide in rice grains were below the maximum residue limit (MRL of 0.5 mg/kg set by Japan, whereas the final residues in rice husk and straw were still high (the highest value reached 1.36 mg/kg in rice husk and 0.83 mg/kg in rice straw. The results indicated that the highest residue in rice grain was 0.23 mg/kg when PHI was 21 d, and only 6.9–11.0% of acute risk quotient of thifluzamide was occupied by the dietary daily intake in Chinese population consuming rice.

Characterization of Polypropylene Green Composites Reinforced by Cellulose Fibers Extracted from Rice Straw

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Ngo Dinh Vu

2018-01-01

Full Text Available Polypropylene (PP based green composites containing 10, 20, 30, 40 and 50 wt% of cellulose fibers (CFs which were extracted from rice straw were successfully prepared by melt blend method. The CFs washed with H2O2 after alkaline extraction showed lower water absorption than that not washed with H2O2. The thermal, mechanical, and biodegradation properties of composites were also investigated. The 10% weight loss temperature of the composites was decreased with the increasing CFs content, but all the composites showed over 300°C. Young’s modulus and flexural properties of PP were improved by blending PP with CFs. The pure PP showed no degradability, but the PP/CFs composites degraded from about 3 to 23 wt%, depending on CFs content after being buried in soil for 50 days. These PP/CFs composites with high thermal, mechanical properties and biodegradability may be useful as green composite materials for various environmental fields.

The utilization of alkali-treated rice straw supplemented with cheap non-protein nitrogen in buffalo production in Sri Lanka

International Nuclear Information System (INIS)

Jayasuriya, M.C.N.; Karunaratne, M.

1984-01-01

Two experiments were undertaken to evaluate the feeding value of rice straw, with special emphasis on rumen function, on swamp buffalo in Sri Lanka. In Experiment 1 three rumen-fistulated buffaloes of average live weight 240 kg were used to compare three rations containing straw supplemented with 4% urea, straw 'ensiled' for 21 days with a solution of 4% urea (urea/ammonia treatment) and straw treated with a 4% solution of sodium hydroxide. The urea-ammonia and sodium hydroxide treatments were superior to urea supplementation in increasing apparent digestibility of the diet, total volatile fatty acid concentrations and acetate production rate in the rumen. In Experiment 2 three treatments were compared using the same three fistulated buffaloes. Treatments 1 and 2 were as in Experiment 1, but for treatment 3, to 4% urea ensiled straw as in Experiment 1 was added 5 wt% finely chopped, fresh glyricidia leaves prior to ensiling to supply urease, enhancing ammonia production from urea. The digestibility of the glyricidia-containing ration was similar to that of the ration with straw treated for 21 days. Acetate production and total volatile fatty acid concentration were also similar for the two treatments. The increased digestibility of the diet and the apparent increased volatile fatty acid production in the rumen explain the increases in live weight gain and milk production in cattle and buffalo fed urea-ammonia treated rice straw. Adding glyricidia at the commencement of ensiling can be recommended to reduce the ensiling time of treated straw. (author)

Buried straw layer and plastic mulching increase microlfora diversity in salinized soil

Institute of Scientific and Technical Information of China (English)

LI Yu-yi; PANG Huan-cheng; HAN Xiu-fang; YAN Shou-wei; ZHAO Yong-gan; WANG Jing; ZHAI Zhen; ZHANG Jian-li

2016-01-01

Salt stress has been increasingly constraining crop productivity in arid lands of the world. In our recent study, salt stress was aleviated and crop productivity was improved remarkably by straw layer burial plus plastic iflm mulching in a saline soil. However, its impact on the microlfora diversity is not wel documented. Field micro-plot experiments were conducted from 2010 to 2011 using four tilage methods: (i) deep tilage with plastic iflm mulching (CK), (i) straw layer burial at 40 cm (S), (ii) straw layer burial plus surface soil mulching with straw material (S+S), and (iv) plastic iflm mulching plus buried straw layer (P+S). Culturable microbes and predominant bacterial communities were studied; based on 16S rDNA, bacterial com-munity structure and abundance were characterized using denaturing gradient gel electrophoresis (DGGE) and polymerase chain reaction (PCR). Results showed that P+S was the most favorable for culturable bacteria, actinomyces and fungi and induced the most diverse genera of bacteria compared to other tilage methods. Soil temperature had signiifcant positive correlations with the number of bacteria, actinomyces and fungi (P<0.01). However, soil water was poorly correlated with any of the microbes. Salt content had a signiifcant negative correlation with the number of microbers, especialy for bacteria and fungi (P<0.01). DGGE analysis showed that the P+S exhibited the highest diversity of bacteria with 20 visible bands folowed by S+S, S and CK. Moreover, P+S had the highest similarity (68%) of bacterial communities with CK. The major bacterial genera in al soil samples wereFirmicutes,Proteobacteria andActinobacteria. Given the considerable increase in microbial growth, the combined use of straw layer burial and plastic iflm mulching could be a practical option for aleviating salt stress effects on soil microbial community and thereby improving crop production in arid saline soils.

Improve the Recovery of Fermentable Sugar from Rice Straw by Sonication and Its Mathematical Modeling

Science.gov (United States)

Bhattacharyya, Saurav; Dutta, Somenath; Datta, Sidhartha; Bhattacharjee, Chiranjib

2012-08-01

Rice straw is waste renewable agricultural biomass, which contains sufficient amount of fermentable sugars like glucose, galactose fructose, xylose etc. These sugars can be treated with fermentation pathway to produce ethanol. Hydrolysis of pretreated rice straw in dilute sulfuric acid was investigated at different acid concentrations (0.25-0.75 % w/v), and sonication was carried out to improve the extent of sugar extraction. The current work examines the effect of sonication on extraction of total reducing sugar (TRS) and an empirical mathematical model has been established to predict it. Effects of various operating variables of sonication, including amplitude (60-100 %), cycle (0.6-1.0), treatment time (0-15 min) have been analyzed for each acid concentration. Observation shows that on optimization of the sonication conditions (100 % amplitude, 0.8 cycle and 10 min) around 90 % improvement of TRS extraction occurs at 0.5 % (w/v) acid concentration.

Enhanced yields and soil quality in a wheat-maize rotation using buried straw mulch.

Science.gov (United States)

Guo, Zhibin; Liu, Hui; Wan, Shuixia; Hua, Keke; Jiang, Chaoqiang; Wang, Daozhong; He, Chuanlong; Guo, Xisheng

2017-08-01

Straw return may improve soil quality and crop yields. In a 2-year field study, a straw return method (ditch-buried straw return, DB-SR) was used to investigate the soil quality and crop productivity effects on a wheat-corn rotation system. This study consisted of three treatments, each with three replicates: (1) mineral fertilisation alone (CK0); (2) mineral fertilisation + 7500 kg ha -1 wheat straw incorporated at depth of 0-15 cm (NPKWS); and (3) mineral fertilisation + 7500 kg ha -1 wheat straw ditch buried at 15-30 cm (NPKDW). NPKWS and NPKDW enhanced crop yield and improved soil biotical properties compared to mineral fertilisation alone. NPKDW contributed to greater crop yields and soil nutrient availability at 15-30 cm depths, compared to NPKWS treatment. NPKDW enhanced soil microbial activity and bacteria species richness and diversity in the 0-15 cm layer. NPKWS increased soil microbial biomass, bacteria species richness and diversity at 15-30 cm. The comparison of the CK0 and NPKWS treatments indicates that a straw ditch buried by digging to the depth of 15-30 cm can improve crop yields and soil quality in a wheat-maize rotation system. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Eating behavior of Ongole crossbred and Limousin crossbred steers fed fermented rice straw and concentrate

Directory of Open Access Journals (Sweden)

Agung Purnomoadi

2003-12-01

Full Text Available A study on eating behavior of Ongole Crossbred (OC and Limousin Crossbred (LC steers (aged 9 months fed fermented rice straw and concentrate has been carried out. Rice straw and concentrate were given in 60:40 ratio. Rice straw was fermented by commercial starter (BioP 2000 Z, while concentrate was composed of commercial concentrate and soybean pulp (by-product of soy-sauce industry. The diet was set to meet the dry matter (DM requirement at 3.0% of liveweight. Eating behaviour was measured from 3 days continuously observation. Chewing number was accounted by halter equipped with tape-switch in jaw side and was recorded every 1/10 second in connected PC. The results showed that DMI of both OC (3.21 kg and LC (4.18 kg was similar, being 2.8% LW. However, chewing number of OC (133808 chews/d was higher than that of LC (106353 chews/d. Chewing for eating and for rumination in OC (86995 and 46813 chews was higher than of LC (67628 and 38725 chews. Chewing efficiency for eating in OC (0.041 g DMI/chew was lower than that of LC (0.066 g DMI/chew. Similar tendency was observed in chewing efficiency for rumination that OC (0.080 g DMI/chew was lower than that of LC (0.109 g DMI/chew. The conclusion is LC has a better chewing efficiency than of OC and it was pointed to different jaw size between OC and LC.

Straw-to-soil or straw-to-energy? An optimal trade off in a long term sustainability perspective

International Nuclear Information System (INIS)

Monteleone, Massimo; Cammerino, Anna Rita Bernadette; Garofalo, Pasquale; Delivand, Mitra Kami

2015-01-01

Highlights: • Energy balance and GHG savings of a straw-to-electricity value chain were determined. • An “expanded” LCA was performed, from farm field to electricity delivery. • Both direct and indirect factors of land use change have been considered in the analysis. • No-tillage and crop rotation significantly improved the system performance. • A win–win, sustainable solution for the energy use of straw has been identified. - Abstract: This study examined some management strategies of wheat cultivation system and its sustainability in using straw as an energy feedstock. According to the EU regulatory framework on biofuels, no GHG emissions should be assigned to straws when they are used for energy. Given this relevance in the current energy policy, it is advisable to include all possible marginal effects related to land use, resource utilization and management changes in the comparison of different biomass options. Coherently, an expanded life cycle assessment (LCA) was applied to include the upstream cultivation phase and to make a comparison between “straw to soil” and “straw to energy”. Different crop management conditions in Southern Italy were simulated, by using the CropSyst model, to estimate the long-term soil organic carbon and annual N 2 O soil emissions. Three wheat cropping systems were considered: the conventional single wheat system without straw removal (W0) and with partial straw removal (W1), together with a no-tillage “wheat-wheat-herbage” rotation system with partial straw removal (W2). The results of the simulations were integrated in the LCA to compare fossil energy consumption and greenhouse gas (GHG) emissions of straw-to-electricity with respect to the fossil-based electricity system. The “improved” rotational wheat cropping system (W2) gave the best performance in terms both of GHG savings and fossil displacement, thus stressing that straw use for energy generation in parallel with the optimization of the

Lignocellulosic residues for production of electricity, biogas or second generation biofuel: A case study of technical and sustainable potential of rice straw in Mali

DEFF Research Database (Denmark)

Nygaard, Ivan; Dembelé, Filifing; Daou, Ibrahima

2016-01-01

Biomass from agricultural residues, especially lignocellulosic biomass, is not only seen as a sustainable biomass source for the production of electricity, but increasingly as a resource for the production of biogas and second generation biofuel in developing countries. Based on empirical research...... in an irrigated rice-growing area, Office du Niger, in Mali, this article builds scenarios for the sustainable potential of rice straw. The paper concludes that there is great uncertainty regarding the size of the sustainable resources of rice straw available for energy, but that the most likely scenario...

Effects of application of corn straw on soil microbial community structure during the maize growing season.

Science.gov (United States)

Lu, Ping; Lin, Yin-Hua; Yang, Zhong-Qi; Xu, Yan-Peng; Tan, Fei; Jia, Xu-Dong; Wang, Miao; Xu, De-Rong; Wang, Xi-Zhuo

2015-01-01

This study investigated the influence of corn straw application on soil microbial communities and the relationship between such communities and soil properties in black soil. The crop used in this study was maize (Zea mays L.). The five treatments consisted of applying a gradient (50, 100, 150, and 200%) of shattered corn straw residue to the soil. Soil samples were taken from May through September during the 2012 maize growing season. The microbial community structure was determined using phospholipid fatty acid (PLFA) analysis. Our results revealed that the application of corn straw influenced the soil properties and increased the soil organic carbon and total nitrogen. Applying corn straw to fields also influenced the variation in soil microbial biomass and community composition, which is consistent with the variations found in soil total nitrogen (TN) and soil respiration (SR). However, the soil carbon-to-nitrogen ratio had no effect on soil microbial communities. The abundance of PLFAs, TN, and SR was higher in C1.5 than those in other treatments, suggesting that the soil properties and soil microbial community composition were affected positively by the application of corn straw to black soil. A Principal Component Analysis indicated that soil microbial communities were different in the straw decomposition processes. Moreover, the soil microbial communities from C1.5 were significantly different from those of CK (p soil and significant variations in the ratio of monounsaturated-to-branched fatty acids with different straw treatments that correlated with SR (p soil properties and soil microbial communities and that these properties affect these communities. The individual PLFA signatures were sensitive indicators that reflected the changes in the soil environment condition. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Transformations of sup(15)N labelled urea applied to a soil with maize strain incorporation under continuous flood

International Nuclear Information System (INIS)

Colaco, W.

1991-01-01

A greenhouse experiment with deep placed sup(15)N-labelled urea was conducted in an Aluvial soil in which maize straw was incorporated. The transformations of total-N, NH sub(4) sup(+) -N, and NO sub(3) sup(-) -N, - were investigated under continuous flooded conditions in soil planted or not to rice. Total -N and inorganic-N levels decreased in both conditions. The rapid inorganic decrease in planted soil would be mainly due to assimilation by the rice plants. However losses occurred in all cases. Such losses increased in the absence of rice plants and seemed to be mainly to nitrification - denitrification mechanisms although NH sub(3) volatilization could also be involved. Dry matter yield and N-uptake by rice increased with increasing rate of N-application. Maize straw was an important source of N for rice. N losses are modified by the incorporation of maize straw. (author)

Effect of water management, tillage options and phosphorus status on arsenic uptake in rice.

Science.gov (United States)

Talukder, A S M H M; Meisner, C A; Sarkar, M A R; Islam, M S

2011-05-01

High arsenic (As) concentrations in soil may lead to elevated concentrations of arsenic in agricultural products. Field experiments were conducted to examine the effects of water management (WM) and Phosphorus (P) rates on As uptake, rice growth, yield and yield attributes of winter (boro) and monsoon (aman) rice in an As contaminated soil-water at Gobindagonj, Gaibandha, Bangladesh in 2004 and 2005. Significantly, the highest average grain yields (6.88±0.07 t ha(-1) in boro 6.38±0.06 t ha(-1) in aman) were recorded in permanent raised bed (PRB; aerobic WM: Eh=+360 mV) plus 100% P amendment. There was a 12% yield increase over conventional till on flat (CTF; anaerobic WM: Eh=-56 mV) at the same P level. In boro, the As content in grain and As content in straw were about 3 and 6 times higher in CTF compared to PRB, respectively. The highest total As content (0.646±0.01 ppm in grain and 10.93±0.19 ppm in straw) was recorded under CTF, and the lowest total As content (0.247±0.01 and 1.554±0.09 ppm in grain and straw, respectively) was recorded under PRB (aerobic WM). The results suggest that grain and straw As are closely associated in boro rice. The furrow irrigation approach of the PRB treatments consistently reduced irrigation input by 29-31% for boro and 27-30% for aman rice relative to CTF treatments in 2004 and 2005, respectively, thus reducing the amount of As added to the soil from the As-contaminated irrigation water. Yearly, 30% less As was deposited to the soil compared to CTF system through irrigation water during boro season. High As concentrations in grain and straw in rice grown using CTF in the farmers' field, and the fact that using PRB reduced grain As concentrations to value less than half of the proposed food hygiene standard. Copyright © 2010 Elsevier Inc. All rights reserved.

Response Of Lowland Rice To Soil Compaction

International Nuclear Information System (INIS)

Idawati; Haryanto

2000-01-01

Soil compaction, as a new tillage practice for paddy soil, is to substitute pudding in order to reduce land preparation cost. To study response of lowland rice to soil compaction, a pot experiment has been conducted which took place in the greenhouse of P3TIR-BATAN. Soil for experiment was taken from pusakanegara. Two factors (degree of soil compaction and rice variety) were combined. Degree of compaction was split into 3 levels (DI = normal; D215% more compact than normal; 30 % more compact than normal), and rice variety into 2 levels (IR64 and Atomita IV). KH 2 32 PO 4 solution was injected into the soil surrounding rice clump to test the root activity at blooming stage of rice plant. Data resulted from this experiment is presented together with additional data from some other experiments of fertilization in the research s erie to study soil compaction. Some information's from experiment results are as following. Both rice varieties tested gave the same response to soil compaction. Root activity, according to data of 32 P absorbed by plant, was not harmed by soil compaction at the degree tested in the experiment. This prediction is supported by the growth by rice observed at generative growth stage, in pot experiment as well as in field experiment, which showed that soil compaction tested did not decrease rice yield but in opposite in tended to increase the yield. In practising soil compaction in land preparation, fertilizers should be applied by deep placement to have higher increasing is rice yield

Effects of earthworm (Eisenia fetida) and wheat (Triticum aestivum) straw additions on selected properties of petroleum-contaminated soils.

Science.gov (United States)

Callaham, Mac A; Stewart, Arthur J; Alarcón, Clara; McMillen, Sara J

2002-08-01

Current bioremediation techniques for petroleum-contaminated soils are designed to remove contaminants as quickly and efficiently as possible, but not necessarily with postremediation soil biological quality as a primary objective. To test a simple postbioremediation technique, we added earthworms (Eisenia fetida) or wheat (Triticum aestivum) straw to petroleum land-farm soil and measured biological quality of the soil as responses in plant growth, soil respiration, and oil and grease (O&G) and total petroleum hydrocarbon (TPH) concentrations. Results indicated that plant growth was greater in earthworm-treated land-farm soil. Furthermore, addition of wheat straw resulted in greater total respiration in all soils tested (land-farm soil, noncontaminated reference soil, and a 1:1 mixture of land-farm and reference soils). We observed a 30% increase in soil respiration in straw-amended oily soil, whereas respiration increased by 246% in straw-amended reference soil. Much of the difference between oily and reference soils was attributable to higher basal respiration rates of nonamended oily soil compared to nonamended reference soil. Addition of earthworms resulted in greater total respiration of all soil and straw treatments except two (the land-farm and the 1:1 mixture soil treatments without straw). Straw and earthworm treatments did not affect O&G or TPH concentrations. Nevertheless, our findings that earthworm additions improved plant growth and that straw additions enhanced microbial activity in land-farm soil suggest that these treatments may be compatible with plant-based remediation techniques currently under evaluation in field trials, and could reduce the time required to restore soil ecosystem function.

Design considerations for a farm-scale biogas plant based on pilot-scale anaerobic digesters loaded with rice straw and piggery wastewater

International Nuclear Information System (INIS)

Mussoline, Wendy; Esposito, Giovanni; Lens, Piet; Garuti, Gilberto; Giordano, Andrea

2012-01-01

Two pilot-scale (1 m 3 ) digesters filled with untreated rice straw and co-digested with raw pig wastewater were operated to obtain design parameters for a farm-scale biogas plant. Both digesters contained 50 kg of dry straw mixed with diluted pig wastewater to create dry digestion conditions (20% TS) and operated for 189 days with leachate recirculation. Digester A was designed for optimum performance (150 L of pig wastewater and mesophilic temperatures) while Digester B was designed to establish minimum inputs (60 L of pig wastewater at ambient temperatures). The pig wastewater provided sufficient buffering capacity to maintain appropriate pH values (between 7.0 and 8.1) and nutrient balances (TOC to TKN ratios of 20 in Digester A and 32 in Digester B). Total biogas production was 22,859 L in Digester A and 1420 L from Digester B, resulting in specific methane yields of 231 and 12 L CH 4 /kgVS added, respectively. Gas production in Digester A was directly correlated with temperature, but the overall lack of methanogenic activity was caused primarily by the reduced wastewater volume. Two theoretical farm-scale scenarios (considering both untreated and pretreated rice straw) were developed for a 100-ha rice farm. Either scenario can produce 100,000 m 3 CH 4 per year, yielding 328 MWh. Major differences including heat input, space requirements, loading frequency, digester volume, engine size, wastewater quantities, and additives are quantitatively defined. The appropriate choice for a farm-scale operation is the simplest model using untreated rice straw without additives, although six times more heat and twice as much reactor volume is required. -- Highlights: ► The co-digestion of untreated rice straw and piggery wastewater is investigated. ► Gas production increases with the volume of pig wastewater added and temperature. ► Pig wastewater alone can provide appropriate buffering capacity and nutrient balance. ► Pilot-scale results are used to establish

Tillage practices and straw-returning methods affect topsoil bacterial community and organic C under a rice-wheat cropping system in central China

Science.gov (United States)

Guo, Lijin; Zheng, Shixue; Cao, Cougui; Li, Chengfang

2016-09-01

The objective of this study was to investigate how the relationships between bacterial communities and organic C (SOC) in topsoil (0-5 cm) are affected by tillage practices [conventional intensive tillage (CT) or no-tillage (NT)] and straw-returning methods [crop straw returning (S) or removal (NS)] under a rice-wheat rotation in central China. Soil bacterial communities were determined by high-throughput sequencing technology. After two cycles of annual rice-wheat rotation, compared with CT treatments, NT treatments generally had significantly more bacterial genera and monounsaturated fatty acids/saturated fatty acids (MUFA/STFA), but a decreased gram-positive bacteria/gram-negative bacteria ratio (G+/G-). S treatments had significantly more bacterial genera and MUFA/STFA, but had decreased G+/G- compared with NS treatments. Multivariate analysis revealed that Gemmatimonas, Rudaea, Spingomonas, Pseudomonas, Dyella, Burkholderia, Clostridium, Pseudolabrys, Arcicella and Bacillus were correlated with SOC, and cellulolytic bacteria (Burkholderia, Pseudomonas, Clostridium, Rudaea and Bacillus) and Gemmationas explained 55.3% and 12.4% of the variance in SOC, respectively. Structural equation modeling further indicated that tillage and residue managements affected SOC directly and indirectly through these cellulolytic bacteria and Gemmationas. Our results suggest that Burkholderia, Pseudomonas, Clostridium, Rudaea, Bacillus and Gemmationas help to regulate SOC sequestration in topsoil under tillage and residue systems.

Carbon dioxide emission from maize straw incubated with soil under various moisture and nitrogen levels

International Nuclear Information System (INIS)

Abro, S.A.; Tian, X.; Hussain, Q.; Talpur, M.; Singh, U.

2012-01-01

A laboratory incubation experiment was conducted to investigate the decomposition of maize straw incorporated into soil amended with nitrogen (N) and moisture (M) levels. Clay loam topsoil amended with maize straw was adjusted to four initial nitrogen treatments (C/N ratios of 72, 36, 18, and 9) and four moisture levels (60%, 70%, 80% and 90 % of field capacity) for the total of 16 treatments and incubated at 20 deg. C for 51 days. CO/sub 2/-C evolved was regularly recorded for all treatments during entire incubation period. Results showed that the mixing of straw with soil accelerated decomposition rates and enhanced cumulative CO/sub 2/-C production. The incorporation of straw brought about 50% increase in the cumulative CO/sub 2/-C production as compared with controls. About 45% of added maize straw C was mineralized to CO/sub 2/-C in 51 days. We conclude that incorporation of straw into soil along with the addition of N and moisture levels significantly affected CO/sub 2/-C evolution, cumulative CO/sub 2-C/, C mineralization and soil organic carbon deposition. The CO/sub 2/ emission was in positive correlation with (R2=0.99) N, moisture and incubation time (days). The straw returning into soil may enhance carbon pools and, thus will improve soil and environmental quality. (author)

Fractionation of hemicelluloses and lignin from rice straw by combining autohydrolysis and optimised mild organosolv delignification

NARCIS (Netherlands)

Moniz, Patrícia; Lino, João; Duarte, Luís C.; Roseiro, Luísa B.; Boeriu, Carmen G.; Pereira, Helena; Carvalheiro, Florbela

2015-01-01

An integrated strategy was followed to valorise rice straw, one of the most relevant biomass feedstocks available worldwide, to selectively recover solubilised hemicelluloses and lignin. The pathway encompassed the use of autohydrolysis to hydrolyse the hemicelluloses and an ethanol-based

Three-dimensional interconnected porous graphitic carbon derived from rice straw for high performance supercapacitors

Science.gov (United States)

Jin, Hong; Hu, Jingpeng; Wu, Shichao; Wang, Xiaolan; Zhang, Hui; Xu, Hui; Lian, Kun

2018-04-01

Three-dimensional interconnected porous graphitic carbon materials are synthesized via a combination of graphitization and activation process with rice straw as the carbon source. The physicochemical properties of the three-dimensional interconnected porous graphitic carbon materials are characterized by Nitrogen adsorption/desorption, Fourier-transform infrared spectroscopy, X-ray diffraction, Raman spectroscopy, Scanning electron microscopy and Transmission electron microscopy. The results demonstrate that the as-prepared carbon is a high surface area carbon material (a specific surface area of 3333 m2 g-1 with abundant mesoporous and microporous structures). And it exhibits superb performance in symmetric double layer capacitors with a high specific capacitance of 400 F g-1 at a current density of 0.1 A g-1, good rate performance with 312 F g-1 under a current density of 5 A g-1 and favorable cycle stability with 6.4% loss after 10000 cycles at a current density of 5 A g-1 in the aqueous electrolyte of 6M KOH. Thus, rice straw is a promising carbon source for fabricating inexpensive, sustainable and high performance supercapacitors' electrode materials.

High level expression of Acidothermus cellulolyticus β-1, 4-endoglucanase in transgenic rice enhances the hydrolysis of its straw by cultured cow gastric fluid

Energy Technology Data Exchange (ETDEWEB)

Chou, Hong L.; Dai, Ziyu; Hsieh, Chia W.; Ku, Maurice S.

2011-12-10

Large-scale production of effective cellulose hydrolytic enzymes is the key to the bioconversion of agricultural residues to ethanol. The goal of this study was to develop a rice plant as a bioreactor for the large-scale production of cellulose hydrolytic enzymes via genetic transformation, and to simultaneously improve rice straw as an efficient biomass feedstock for conversion of cellulose to glucose. In this study, the cellulose hydrolytic enzyme {beta}-1, 4-endoglucanase (E1) from the thermophilic bacterium Acidothermus cellulolyticus was overexpressed in rice through Agrobacterium-mediated transformation. The expression of the bacterial gene in rice was driven by the constitutive Mac promoter, a hybrid promoter of Ti plasmid mannopine synthetase promoter and cauliflower mosaic virus 35S promoter enhancer with the signal peptide of tobacco pathogenesis-related protein for targeting the protein to the apoplastic compartment for storage. A total of 52 transgenic rice plants from six independent lines expressing the bacterial enzyme were obtained, which expressed the gene at high levels with a normal phenotype. The specific activities of E1 in the leaves of the highest expressing transgenic rice lines were about 20 fold higher than those of various transgenic plants obtained in previous studies and the protein amounts accounted for up to 6.1% of the total leaf soluble protein. Zymogram and temperature-dependent activity analyses demonstrated the thermostability of the enzyme and its substrate specificity against cellulose, and a simple heat treatment can be used to purify the protein. In addition, hydrolysis of transgenic rice straw with cultured cow gastric fluid yielded almost twice more reducing sugars than wild type straw. Taken together, these data suggest that transgenic rice can effectively serve as a bioreactor for large-scale production of active, thermostable cellulose hydrolytic enzymes. As a feedstock, direct expression of large amount of cellulases in

Techno-economic analysis of bioethanol production from rice straw by liquid-state fermentation

Science.gov (United States)

Hidayata, M. H. M.; Salleh, S. F.; Riayatsyahb, T. M. I.; Aditiyac, H. B.; Mahliaa, T. M. I.; Shamsuddina, A. H.

2016-03-01

Renewable energy is the latest approach of the Malaysian government in an effort to find sustainable alternative energy sources and to fulfill the ever increasing energy demand. Being a country that thrives in the service and agricultural sector, bioethanol production from lignocellulosic biomass presents itself as a promising option. However, the lack of technical practicality and complexity in the operation system hinder it from being economically viable. Hence, this research acquired multiple case studies in order to provide an insight on the process involved and its implication on production as well as to obtain a cost analysis of bioethanol production. The energy input and cost of three main components of the bioethanol production which are the collection, logistics, and pretreatment of rice straw were evaluated extensively. The theoretical bioethanol yield and conversion efficiency obtained were 250 L/t and 60% respectively. The findings concluded that bioethanol production from rice straw is currently not economically feasible in Malaysia’s market due to lack of efficiency in the pretreatment phase and overbearing logistics and pretreatment costs. This work could serve as a reference to future studies of biofuel commercialization in Malaysia.

Semi-solid microbial fermentation of rice and wheat straw for protein enrichment and increased digestibility

Energy Technology Data Exchange (ETDEWEB)

Balasubramanya, R.H.; Bhatawdekar, S.P.

1980-12-01

Rice and wheat straws were hydrolyzed in various concentrations of sulfuric acid at different temperatures and different water: substrate ratios. The maximum amount of sugars of about 30-34% was released when heated at 121 degrees C with 0.5 N H2SO4 at a water: substrate ratio of 3:1. The pH of the hydrolyzed straws was raised to 5.0-5.5 with 5 N NH4OH. Such ammoniated straws were inoculated with the cultures of Penicillium funiculosum Thom. and Candida utilis (Henneb.) Lodder and Kreger-van Rij, and fermentation was carried out on semi-solid substrate for 5-7 days at room temperature. The fermentation resulted in 37-180% increase in crude protein, 23-100% increase in crude fat and 20-30% increase in the digestibility. (Refs. 29).

Comparative Study on Characteristics and Potential of Rice Straws and Dry Leaves as a Binder in Refuse Derived Fuel (RDF)

International Nuclear Information System (INIS)

Zulhafizal Othman; Lias, K.; Hashim, N.H.; Clement, F.N.

2013-01-01

Integrated waste management systems are one of the greatest challenges in order to develop the green environment. In this research, two types of binder were chosen in producing of Refuse Derived Fuel (RDF) which is rice straws and dry leaves. The objective of the research is to identify which types of binder that can give the optimum performance. This two binder was mixed with paper and plastic waste with controlled mixing ratio which is 3:1 (ratio 1), 3:1.5(ratio 2) and 3:2 (ratio 3). In order to identify the optimum ratio of RDF, 45 number of samples was prepared and their properties such as moisture content, carbon content, sulfur content, chlorine content and calorific value were evaluated. Result indicated that samples with rice straw as a binder give the optimum result with the ratio of 3:1. The optimum values of the carbon content is 50.9 %, moisture content is 5.5 %, chlorine content is 0.0 %, sulfur content is 2.1 % and calorific value is 29.0 MJ/ kg. Hence, rice straws shows a great potential to be used as binder in production of RDF. (author)

Adsorption, immobilization and activity of cellulase in soil: the impacts of maize straw and its humification

Directory of Open Access Journals (Sweden)

Ali Akbar Safari Sinegani

2013-12-01

Full Text Available The present work aimed to study some aspects of sorption and immobilization of cellulase molecules on soil components by the analysis of the reactions of cellulase in a soil treated with different levels of maize residue and incubated for 90 days. The analysis of variance showed that the effects of the treatments of maize straw, incubation time and their interaction on cellulase adsorption, desorption and immobilization were statistically significant. The adsorption and immobilization capacities of soil by application of maize straw increased significantly. However they decreased with decreasing the soil organic matter (SOM after 45 days of incubation. The desorption of adsorbed cellulase molecules from the soil by washing with distilled water depended on the SOM contents and its humification. The binding strength of cellulase molecule with fresh miaze straw was significantly stronger than that with humified maize straw. The immobilized cellulase activity, particularly its specific activity increased significantly by increasing the OC contents in the soil treated with maize straw.

Effects of Two Soil Amendments from Steel Slag on Rice Growth and Nitrogen, Phosphorus and Potassium Uptake

Directory of Open Access Journals (Sweden)

ZHANG Lu

2017-08-01

Full Text Available A pot experiment was conducted to investigate the effects of two soil amendments(W and Y derived from steel slag and their application rates(0.74, 1.47, 2.94, 5.88 g·kg-1 and 11.76 g·kg-1 for W; 1.47, 2.94, 5.88, 11.76 g·kg-1 and 23.52 g·kg-1 for Y on rice growth. The results showed that no significant change in rice yield was found following W amendments; conversely, a 20% increase in rice yield was observed following Y amendments at rates of 11.76 g·kg-1 and 23.52 g·kg-1 as compared with NPK treatments. Y amendment at rates of 5.88~23.52 g·kg-1 increased straw mass by 24.02%~35.23% when compared with NPK treatments. Combined application of Y amendments and NPK fertilizers increased subsequent N, P and K uptake by rice by 12.61%~21.55%, 7.63%~38.31% and 11.89%~54.13%, respectively. The results indicated Y amendments could effectively accelerate subsequent rice growth at high application rates by increasing nutrient uptake in the soil studied(pH 6.51; Conversely, we observed no significant effects with W amendments.

Improving the mixing performances of rice straw anaerobic digestion for higher biogas production by computational fluid dynamics (CFD) simulation.

Science.gov (United States)

Shen, Fei; Tian, Libin; Yuan, Hairong; Pang, Yunzhi; Chen, Shulin; Zou, Dexun; Zhu, Baoning; Liu, Yanping; Li, Xiujin

2013-10-01

As a lignocellulose-based substrate for anaerobic digestion, rice straw is characterized by low density, high water absorbability, and poor fluidity. Its mixing performances in digestion are completely different from traditional substrates such as animal manures. Computational fluid dynamics (CFD) simulation was employed to investigate mixing performances and determine suitable stirring parameters for efficient biogas production from rice straw. The results from CFD simulation were applied in the anaerobic digestion tests to further investigate their reliability. The results indicated that the mixing performances could be improved by triple impellers with pitched blade, and complete mixing was easily achieved at the stirring rate of 80 rpm, as compared to 20-60 rpm. However, mixing could not be significantly improved when the stirring rate was further increased from 80 to 160 rpm. The simulation results agreed well with the experimental results. The determined mixing parameters could achieve the highest biogas yield of 370 mL (g TS)(-1) (729 mL (g TS(digested))(-1)) and 431 mL (g TS)(-1) (632 mL (g TS(digested))(-1)) with the shortest technical digestion time (T 80) of 46 days. The results obtained in this work could provide useful guides for the design and operation of biogas plants using rice straw as substrates.

The effect of straw and wood gasification biochar on carbon sequestration, selected soil fertility indicators and functional groups in soil: an incubation study

DEFF Research Database (Denmark)

Hansen, Veronika; Müller-Stöver, Dorette; Munkholm, Lars Juhl

2016-01-01

Annual removal of crop residues may lead to depletion of soil organic carbon and soil degradation. Gasification biochar (GB), the carbon-rich byproduct of gasification of biomass such as straw and wood chips, may be used for maintaining the soil organic carbon content and counteract soil degradat......Annual removal of crop residues may lead to depletion of soil organic carbon and soil degradation. Gasification biochar (GB), the carbon-rich byproduct of gasification of biomass such as straw and wood chips, may be used for maintaining the soil organic carbon content and counteract soil......, the addition of straw resulted in a high soil respiration rate, and about 80% of the added carbonwas respired at the end of the incubation. However, the addition of straw increased aggregate stability and decreased clay dispersibility. Results from Fourier transformed infrared photoacoustic spectroscopy...

Influence of Height Waterlogging on Soil Physical Properties of Potential and Actual Acid Sulphate Soils

Directory of Open Access Journals (Sweden)

Arifin Fahmi

2014-06-01

Full Text Available Water management is main factor that determines the successful of rice cultivation in acid sulphate soil. Soil waterlogging determines the direction and rate of chemical, geochemical and biological reaction in the soil, indirectly these reactions may influence to the changes of soil psycal properties during soil waterlogging process. The experiment was aimed to study the changes of two type of acid sulphate soils physical properties during rice straw decomposition processes. The research was conducted in the greenhouse consisting of the three treatment factors using the completely randomized design with three replications. The first factor was soil type: potential acid sulphate soil (PASS and actual acid sulphate soil (AASS. The second factor was height of water waterlogging: 0.5-1.0 cm (muddy water–level condition and 4.0 cm from above the soil surface (waterlogged. The third factor was organic matter type: rice straw (RS, purun tikus (Eleocharis dulcis (PT and mixed of RS and PT (MX. Soil physical properties such as aggregate stability, total soil porosity, soil permeability, soil particle density and bulk density were observed at the end of experiment (vegetative maximum stage. The results showed that acid sulphate soil type had large effect on soil physicl properties, soil waterlogging decreased aggregate stability, soil particle density and bulk density both of soil type.

IRON DYNAMICS AND ITS RELATION TO SOIL REDOX POTENTIAL AND PLANT GROWTH IN ACID SULPHATE SOIL OF SOUTH KALIMANTAN, INDONESIA

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Wahida Annisa

2017-01-01

Full Text Available Organic matter has a function to maintain reductive conditions and to chelate toxic elements in acid sulphate soils. The study aimed to assess the dynamics of ferrous iron (Fe2+ in acid sulphate soil and its correlation with soil redox potential (Eh and plant growth. The experiment was arranged in two factorial randomized block design with three replications. The first factor was two types of organic matter: (1 control (without organic matter, (2 rice straw and (3 rush weed (Eleocharis dulcis. The second factor was time of decomposition of organic matter: I1 = 2 weeks, I2 = 4 weeks, I3 = 8 weeks, and I4 = 12 weeks (farmer practice. The results showed that concentration of ferrous iron in the soil ranged from 782 to 1308 mg kg-1 during the rice growing season. The highest constant rate of iron reduction (k F2+ was observed on application of rice straw and rush weed with decomposition time of 8 weeks with the k Fe2+ value of 0.016 and 0.011 per day, respectively, while the ferrous iron formation without organic matter had the k Fe2+ value of 0.077 per day. The ferric iron (Fe3+ reduction served as a function of soil Eh as indicated by the negative correlation of ferrous iron and Eh (r = -0.856*. Organic matter decreased exchangeable iron due to chelating reaction. Iron concentration in roots was negatively correlated with soil soluble iron (r = -0.62*. Application of rice straw decomposed for 8 weeks increased the height of rice plant up to 105.67 cm. The score of Fe2+ toxicity at 8 weeks after planting ranged from 2 to 3, so rice crop did not show iron toxicity symptoms. 

Production of single-cell protein from enzymatic hydrolyzate of rice straw

Energy Technology Data Exchange (ETDEWEB)

Taniguchi, M.; Kometani, Y.; Tanaka, M.; Matsuno, R.; Kamikubo, T.

1982-01-01

The components of rice straw, pretreated with sodium chlorite, cellulose and hemicellulose were solubilized with culture filtrate of Pellicularia filamentosa or Trichoderma reesei. The ratio of glucose to total sugar in the solution obtained from the cellulose component with the culture filtrate of Pellicularia filamentosa was approximately twice that of Trichoderma reesei. Ten yeast strains (Candida utilis, C. tropicalis, C. guilliermondii, C. parapsilosis, Torulopsis xylinus, Trichosporon cutaneum, Debaryomyces hansenii, Rhodotorula glutinis, Saccharomyces fragilis and Saccharomyces cerevisiae) were cultivated as test organisms for single-cell protein (SCP) production on sugar solutions obtained from the straw, cellulose and hemicellulose components, pretreated with the culture filtrate of Pellicularia filamentosa. Sugar consumption, in terms of total sugar and cell yield, of the culture with the sugar solution obtained from pretreated straw were; 70% and 6.8 g/l for Candida tropicalis, 56% and 6.4 g/l for Torulopsis xylinus, 76% and 10.1 g/l for Trichosporon cutaneum, and 74% and 7.6 g/l for Candida guilliermondii. In addition, the highest consumption with respect to total sugar (87%) and the best dry cell yield (15.6 g/l) were observed with the culture of Trichosporon cutaneum using the sugar solution obtained from the hemicellulose component. (Refs. 17).

High level expression of Acidothermus cellulolyticus β-1, 4-endoglucanase in transgenic rice enhances the hydrolysis of its straw by cultured cow gastric fluid

Directory of Open Access Journals (Sweden)

Chou Hong

2011-12-01

Full Text Available Abstract Background Large-scale production of effective cellulose hydrolytic enzymes is the key to the bioconversion of agricultural residues to ethanol. The goal of this study was to develop a rice plant as a bioreactor for the large-scale production of cellulose hydrolytic enzymes via genetic transformation, and to simultaneously improve rice straw as an efficient biomass feedstock for conversion of cellulose to glucose. Results In this study, the cellulose hydrolytic enzyme β-1, 4-endoglucanase (E1 gene, from the thermophilic bacterium Acidothermus cellulolyticus, was overexpressed in rice through Agrobacterium-mediated transformation. The expression of the bacterial E1 gene in rice was driven by the constitutive Mac promoter, a hybrid promoter of Ti plasmid mannopine synthetase promoter and cauliflower mosaic virus 35S promoter enhancer, with the signal peptide of tobacco pathogenesis-related protein for targeting the E1 protein to the apoplastic compartment for storage. A total of 52 transgenic rice plants from six independent lines expressing the bacterial E1 enzyme were obtained that expressed the gene at high levels without severely impairing plant growth and development. However, some transgenic plants exhibited a shorter stature and flowered earlier than the wild type plants. The E1 specific activities in the leaves of the highest expressing transgenic rice lines were about 20-fold higher than those of various transgenic plants obtained in previous studies and the protein amounts accounted for up to 6.1% of the total leaf soluble protein. A zymogram and temperature-dependent activity analyses demonstrated the thermostability of the E1 enzyme and its substrate specificity against cellulose, and a simple heat treatment can be used to purify the protein. In addition, hydrolysis of transgenic rice straw with cultured cow gastric fluid for one hour at 39°C and another hour at 81°C yielded 43% more reducing sugars than wild type rice

Rapid molecular screening of black carbon (biochar) thermosequences obtained from chestnut wood and rice straw: A pyrolysis-GC/MS study

International Nuclear Information System (INIS)

Kaal, Joeri; Schneider, Maximilian P.W.; Schmidt, Michael W.I.

2012-01-01

Rice straw and chestnut wood were heated between 200 and 1000 °C (T CHAR ) to produce Black C ‘thermosequences’. The molecular properties of the charred residues were assessed by pyrolysis-GC/MS to investigate the relation between charring intensity and pyrolysis fingerprint. Samples obtained at T CHAR > 500 °C (wood) or >700 °C (straw) gave low quality pyrograms and poor reproducibility because of high thermal stability, but pyrolysis-GC/MS allowed to track the thermal degradation of the main biocomponents (polysaccharides, lignin, methylene chain-based aliphatics, triterpenoids, chlorophyll and proteins) in the lower temperature range, mostly occurring between T CHAR 250 and 500 °C. With increasing T CHAR , the charred residues of these biocomponents lose characteristic functional groups, aromatise and finally condense into non-pyrolysable biomass. The proportions of the pyrolysis products of unspecific origin (benzene, toluene, PAHs, etc.), increase with charring intensity, while the ratios that reflect the abundance of alkyl cross-linkages between aromatic moieties (e.g. benzene/toluene, naphthalene/alkylnaphthalene) decrease. These results provide the guidelines to using pyrolysis-GC/MS for the molecular characterisation of different components in Black C and biochar, which is an important parameter for predicting Black C/biochar behaviour in soil. Results are consistent with earlier studies of these samples using the BPCA (benzenepolycarboxylic acid) method and the ring current-induced 13 C benzene chemical shift NMR (Nuclear Magnetic Resonance) approach. Pyrolysis-GC/MS provides more information on molecular structures in the low temperature range (T CHAR ≤ 500 °C) while the BPCA and NMR ring current methods provide more reliable estimations of charring intensity, especially at higher temperatures (T CHAR ≥ 500 °C). -- Highlights: ► Charred rice straw and chestnut wood (200–1000 °C) analysed by pyrolysis-GC/MS. ► Pyrolysis-GC/MS allows

Impacts of Steel-Slag-Based Silicate Fertilizer on Soil Acidity and Silicon Availability and Metals-Immobilization in a Paddy Soil.

Directory of Open Access Journals (Sweden)

Dongfeng Ning

Full Text Available Slag-based silicate fertilizer has been widely used to improve soil silicon- availability and crop productivity. A consecutive early rice-late rice rotation experiment was conducted to test the impacts of steel slag on soil pH, silicon availability, rice growth and metals-immobilization in paddy soil. Our results show that application of slag at a rate above higher or equal to 1 600 mg plant-available SiO2 per kg soil increased soil pH, dry weight of rice straw and grain, plant-available Si concentration and Si concentration in rice shoots compared with the control treatment. No significant accumulation of total cadmium (Cd and lead (Pb was noted in soil; rather, the exchangeable fraction of Cd significantly decreased. The cadmium concentrations in rice grains decreased significantly compared with the control treatment. In conclusion, application of steel slag reduced soil acidity, increased plant-availability of silicon, promoted rice growth and inhibited Cd transport to rice grain in the soil-plant system.

Influence of Tillage and Mulch on Soil Physical Properties and ...

African Journals Online (AJOL)

... (M0); rice straw, (MRice); wheat straw, (MWheat); plastic sheet, (MPlastic) at 4 t ... Happy seeder and deep tillage along with plastic mulch have positive impact ... use efficiency and yield parameters by creating a favorable soil environment.

Soil contaminated phyto remediation of Pb and cd metal by using rice straw fermented by trichoderma viride that given exposure 250 gray doses of gamma radiation

International Nuclear Information System (INIS)

Yullita SL Andini; Hendrawati; Tri Retno Diah Larasati; Nana Mulyana

2015-01-01

Soil contamination by lead (Pb) and cadmium (Cd) is one form of environmental pollution that is harmful to living organisms. One way to resolve this problem by using phyto remediation with rice straw fermented by Trichoderma viride that given exposure 250 gray doses of gamma radiation. The purpose of this study was to look at the effect of Trichoderma viride fermented hay to improve the ability of Pb and Cd accumulation in the root zone of plants sweet corn (Zea Mays). There are three stages in the research process, namely the stages of SSF (Solid State Fermentation), incorporation, and Land farming. The fermentation process is done during the 16-day trial. Furthermore, the results of the SSF (Solid State Fermentation) mixed in soil that has been contaminated with heavy metals showed that administration of straw result SSF real impact on the value of pH, water content of the four treated samples. Results incorporation process and then applied with a crop of sweet corn (Zea Mays). Accumulation of heavy metals in sweet corn plant, analyzed by AAS analysis instrumentation. The measurement results show that the accumulation of Pb in the roots of plants in the sample K amounted to 33.66 mg/Kg, A sample of 26.80 mg/Kg, the sample B of 51.47 mg/kg, and sample C of 55.70 mg/Kg. While the metals Cd uptake in the roots of corn plants in the sample K showed Cd uptake of 269.65 mg/Kg, the sample A of 445.70 mg/Kg, the sample B of 337.17 mg/Kg and sample C of 336.72 mg/Kg. The phyto remediation process takes place based on the fito-stabilization principle. (author)

Mass and Energy Balances of Dry Thermophilic Anaerobic Digestion Treating Swine Manure Mixed with Rice Straw

OpenAIRE

Zhou, Sheng; Zhang, Jining; Zou, Guoyan; Riya, Shohei; Hosomi, Masaaki

2015-01-01

To evaluate the feasibility of swine manure treatment by a proposed Dry Thermophilic Anaerobic Digestion (DT-AD) system, we evaluated the methane yield of swine manure treated using a DT-AD method with rice straw under different C/N ratios and solid retention time (SRT) and calculated the mass and energy balances when the DT-AD system is used for swine manure treatment from a model farm with 1000 pigs and the digested residue is used for forage rice production. A traditional swine manure trea...

Photosynthates as dominant source of CH4 and CO2 in soil water and CH4 emitted to the atmosphere from paddy fields

Science.gov (United States)

Minoda, Tomomi; Kimura, Mamoto; Wada, Eitaro

1996-09-01

Emission rates of CH4 from paddy soil with and without rice straw applications were measured with pot experiments to estimate the contribution of rice straw to the total CH4 emission during the growth period of rice plants. The CH4 derived from rice straw was calculated to be 44% of the total emission. 13CO2 uptake experiments were also carried out four times from June 30 to September 13, 1994, to estimate the contribution of photosynthesized carbon to CH4 emission. The contribution percentages of photosynthesized carbon to the total CH4 emitted to the atmosphere were 3.8% around June 30, 31% around July 25, 30% around August 19, and 14% around September 13 in the treatment with rice straw applications, and 52% around July 25, 28% around August 19, and 15% around September 13 in the treatment without rice straw applications. They were calculated to be 22% and 29% for the entire growth period in the treatments with and without rice straw applications, respectively. The contribution percentages of photosynthesized carbon to the total CH4 and inorganic carbon (Σ CO2) dissolved in soil water were 1.3%, 30%, 29%, and 34% for dissolved CH4 and 3.0%, 36%, 30% and 28% for dissolved inorganic carbon around June 30, July 25, August l9, and September 13, respectively, in the treatment with rice straw applications. They were 70%, 23%, and 32% for dissolved CH4 and 31%, 16%, and 19% for dissolved inorganic carbon around July 25, August 19, and September 13, respectively, in the treatment without rice straw applications.

Cadmium accumulation in and tolerance of rice (Oryza sativa L.) varieties with different rates of radial oxygen loss.

Science.gov (United States)

Wang, M Y; Chen, A K; Wong, M H; Qiu, R L; Cheng, H; Ye, Z H

2011-06-01

Cadmium (Cd) uptake and tolerance were investigated among 20 rice cultivars based on a field experiment (1.2 mg Cd kg⁻¹ in soil) and a soil pot trial (control, 100 mg Cd kg⁻¹), and rates of radial oxygen loss (ROL) were measured under a deoxygenated solution. Significant differences were found among the cultivars in: (1) brown rice Cd concentrations (0.11-0.29 mg kg⁻¹) in a field soil, (2) grain Cd tolerance (34-113%) and concentrations (2.1-6.5 mg kg⁻¹) in a pot trial, and (3) rates of ROL (15-31 mmol O₂ kg⁻¹ root d.w. h⁻¹). Target hazard quotients were calculated for the field experiment to assess potential Cd risk. Significant negative relationships were found between rates of ROL and concentrations of Cd in brown rice or straw under field and greenhouse conditions, indicating that rice cultivars with higher rates of ROL had higher capacities for limiting the transfer of Cd to rice and straw. Copyright © 2011 Elsevier Ltd. All rights reserved.

Influence of silicon treatment on antimony uptake and translocation in rice genotypes with different radial oxygen loss.

Science.gov (United States)

Zhang, Liping; Yang, Qianqian; Wang, Shiliang; Li, Wanting; Jiang, Shaoqing; Liu, Yan

2017-10-01

Antimony (Sb) pollution in soil may have a negative impact on the health of people consuming rice. This study investigated the effect of silicon (Si) application on rice biomass, iron plaque formation, and Sb uptake and speciation in rice plants with different radial oxygen loss (ROL) using pot experiments. The results demonstrated that Si addition increased the biomass of straw and grain, but had no obvious impact on the root biomass. Indica genotypes with higher ROL underwent greater iron plaque formation and exhibited more Sb sequestration in iron plaque. Silicon treatments increased iron levels in iron plaque from the different genotypes but decreased the total Sb concentration in root, straw, husk, and grain. In addition, Si treatment reduced the inorganic Sb concentrations but slightly increased the trimethylantimony (TMSb) concentrations in rice straw. Moreover, rice straw from hybrid genotypes accumulated higher concentrations of TMSb and inorganic Sb than that from indica genotypes. The conclusions from this study indicate that Sb contamination in rice can be efficiently reduced by applying Si treatment and selecting genotypes with high ROL. Copyright © 2017 Elsevier Inc. All rights reserved.

Anaerobic Co-digestion of Cow Dung and Rice Straw to Produce Biogas using Semi-Continuous Flow Digester: Effect of Urea Addition

Science.gov (United States)

Haryanto, A.; Sugara, B. P.; Telaumbanua, M.; Rosadi, R. A. B.

2018-05-01

The objective this research was to investigate the effect of urea addition on the biogas yield from co-digestion of rice straw and cow dung using semi-continuous anaerobic digester. The experiment was conducted by using self-made semi-continuous anaerobic digester having a working volume of 30 L. Cow dung was provided from Department of Animal Husbandry, University of Lampung; while rice straw was collected from farmer at Way Galih, Tanjung Bintang, South Lampung. Rice straw was sun-dried to about 12% of moisture content and then ground into fine particles. Cow dung and ground straw were mixed at a dung-to-straw ratio of 3:1 based on total solid (TS) and four different urea additions (0, 0.25, 0.65, and 1.30 g/L) were applied to have a C/N ratio between 20 and 30. The mixture was diluted with water to create TS content of 10%. As much as 30 L of the substrate mixture was introduced into the digester as a starting load. The same substrate was added daily at a loading rate of 0.5 L/d. The experiment was made in triplicate and observation was performed for two months. Total and volatile solids of influent and effluent and daily biogas production were observed. The biogas quality was measured by its methane content using gas chromatography. Results showed that urea addition influenced the biogas yield and its quality. Substrate mixture with urea addition of 0.25 g/L (C/N ratio of 27.3) was the best in terms of biogas yield (434.2 L/kgVSr), methane content (50.12%), and methane yield (217.6 L/kgVSr).

The immediate effectiveness of barley straw mulch in reducing soil erodibility and surface runoff generation in Mediterranean vineyards.

Science.gov (United States)

Prosdocimi, Massimo; Jordán, Antonio; Tarolli, Paolo; Keesstra, Saskia; Novara, Agata; Cerdà, Artemi

2016-03-15

Soil and water loss in agriculture is a major problem throughout the world, and especially in Mediterranean areas. Non-conservation agricultural practices have further aggravated the situation, especially in vineyards, which are affected by one of the highest rates of soil loss among cultivated lands. Therefore, it is necessary to find the right soil practices for more sustainable viticulture. In this regard, straw mulching has proven to be effective in other crop and fire affected soils, but, nonetheless, little research has been carried out in vineyards. This research tests the effect of barley straw mulching on soil erosion and surface runoff on vineyards in Eastern Spain where the soil and water losses are non-sustainable. An experiment was setup using rainfall simulation tests at 55 mm h(-1) over 1h on forty paired plots of 0.24 m(2): twenty bare and twenty straw covered. Straw cover varied from 48 to 90% with a median value of 59% as a result of the application of 75 g of straw per m(2). The use of straw mulch resulted in delayed ponding and runoff generation and, as a consequence, the median water loss decreased from 52.59 to 39.27% of the total rainfall. The straw cover reduced the median sediment concentration in runoff from 9.8 to 3.0 g L(-1) and the median total sediment detached from 70.34 to 15.62 g per experiment. The median soil erosion rate decreased from 2.81 to 0.63 Mg ha(-1)h(-1) due to the straw mulch protection. Straw mulch is very effective in reducing soil erodibility and surface runoff, and this benefit was achieved immediately after the application of the straw. Copyright © 2015 Elsevier B.V. All rights reserved.

Optimization of sodium hydroxide pretreatment and enzyme loading for efficient hydrolysis of rice straw to improve succinate production by metabolically engineered Escherichia coli KJ122 under simultaneous saccharification and fermentation.

Science.gov (United States)

Sawisit, Apichai; Jampatesh, Surawee; Jantama, Sirima Suvarnakuta; Jantama, Kaemwich

2018-07-01

Rice straw was pretreated with sodium hydroxide (NaOH) before subsequent use for succinate production by Escherichia coli KJ122 under simultaneous saccharification and fermentation (SSF). The NaOH pretreated rice straw was significantly enhanced lignin removal up to 95%. With the optimized enzyme loading of 4% cellulase complex + 0.5% xylanase (endo-glucanase 67 CMC-U/g, β-glucosidase 26 pNG-U/g and xylanase 18 CMC-U/g dry biomass), total sugar conversion reached 91.7 ± 0.8% (w/w). The physicochemical analysis of NaOH pretreated rice straw indicated dramatical changes in its structure, thereby favoring enzymatic saccharification. In batch SSF, succinate production of 69.8 ± 0.3 g/L with yield and productivity of 0.84 g/g pretreated rice straw and 0.76 ± 0.02 g/L/h, respectively, was obtained. Fed-batch SSF significantly improved succinate concentration and productivity to 103.1 ± 0.4 g/L and 1.37 ± 0.07 g/L/h with a comparable yield. The results demonstrated a feasibility of sequential saccharification and fermentation of rice straw as a promising process for succinate production in industrial scale. Copyright © 2018 Elsevier Ltd. All rights reserved.

Valorization of rice straw waste: production of porcelain tiles

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Álvaro Guzmán A

2015-12-01

Full Text Available Abstract The rice industry generates huge amounts of rice straw ashes (RSA. This paper presents the results of an experimental research work about the incorporation of RSA waste as a new alternative raw material for production of porcelain tiles. The RSA replaces, partially or completely, the non-plastic raw materials (quartz (feldspathic sand in this research and feldspar, that together with the clays, constitute the major constituents of formulations of porcelain tiles. A standard industrial composition (0% RSA and two more compositions in which feldspar and feldspathic sand were replaced with two percentages of RSA (12.5% RSA and 60% RSA were formulated, keeping the clay content constant. The mixtures were processed, reproducing industrial porcelain tile manufacturing conditions by the dry route and fired at peak temperatures varying from 1140-1260 ºC. The results showed that additions of 12.5% RSA in replacement of feldspar and feldspathic sand allowed producing porcelain tiles that did not display marked changes in processing behaviour, in addition to obtain a microstructure and the typical mineralogical phases of porcelain tile. Thus, an alternative use of an agricultural waste material is proposed, which can be translated into economic and environmental benefits.

Effects of wheat straw incorporation on the availability of soil nutrients and enzyme activities in semiarid areas.

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Ting Wei

Full Text Available Soil infertility is the main barrier to dryland agricultural production in China. To provide a basis for the establishment of a soil amelioration technical system for rainfed fields in the semiarid area of northwest China, we conducted a four-year (2007-2011 field experiment to determine the effects of wheat straw incorporation on the arid soil nutrient levels of cropland cultivated with winter wheat after different straw incorporation levels. Three wheat straw incorporation levels were tested (H: 9000 kg hm(-2, M: 6000 kg hm(-2, and L: 3000 kg hm(-2 and no straw incorporation was used as the control (CK. The levels of soil nutrients, soil organic carbon (SOC, soil labile organic carbon (LOC, and enzyme activities were analyzed each year after the wheat harvest. After straw incorporation for four years, the results showed that variable straw amounts had different effects on the soil fertility indices, where treatment H had the greatest effect. Compared with CK, the average soil available N, available P, available K, SOC, and LOC levels were higher in the 0-40 cm soil layers after straw incorporation treatments, i.e., 9.1-30.5%, 9.8-69.5%, 10.3-27.3%, 0.7-23.4%, and 44.4-49.4% higher, respectively. On average, the urease, phosphatase, and invertase levels in the 0-40 cm soil layers were 24.4-31.3%, 9.9-36.4%, and 42.9-65.3% higher, respectively. Higher yields coupled with higher nutrient contents were achieved with H, M and L compared with CK, where these treatments increased the crop yields by 26.75%, 21.51%, and 7.15%, respectively.

Heavy Metal Concentration and Risk Assessment of Soil and Rice in and around an Open Dumpsite in Thailand

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Tanjira Klinsawathom

2017-07-01

Full Text Available This study aimed to determine the heavy metal concentration in the soil and rice in and around Nakhonluang district open dumpsite in Phra Nakhon Si Ayutthaya province of Thailand and to assess the human health risk of these metals. The soil samples demonstrated heavy metal concentrations in the following order: Fe > Mn >Zn > Cu > Cr > Ni > Pb (Cd was not detected, and the average concentrations of each metal in soil from the dumpsite area were higher than those in the surrounding area. The average concentrations of Mn in the soils exceeded the screening level for higher plant protection of the USEPA’s Eco-SSL while the average Zn and Cu concentrations in the soil samples from the dumpsite exceeded the level for good soil and safety to life recommended by LDD. The rice exhibited metal concentrations in the following order: root > straw > grain. A carcinogenic human health risk assessment (RTotal indicated that the values from the soil samples and the rice were at safe levels. The sum of noncarcinogenic hazard values (Cr, Cu, Mn, Ni, Pb, and Zn indicated that exposure to the soils around the dumpsite area may pose adverse health effects (HI < 1 while exposure to the soils in the dumpsite area carries a high risk of causing adverse health effects both in children (HI = 10.5 and adults (HI = 2.18. It is suggested that suitable management measures should be applied to prevent or reduce heavy metal contamination in and around the dumpsite area.

Cultivation of different strains of king oyster mushroom (Pleurotus eryngii) on saw dust and rice straw in Bangladesh.

Science.gov (United States)

Moonmoon, Mahbuba; Uddin, Md Nazim; Ahmed, Saleh; Shelly, Nasrat Jahan; Khan, Md Asaduzzaman

2010-10-01

Pleurotus eryngii is a popular mushroom due to its excellent consistency of cap and stem, culinary qualities and longer shelf life. In Bangladesh, where Pleurotus mushrooms are very popular, P. eryngii may take position among the consumers, but currently this mushroom is not cultivated in large scale there. In this study, 3 strains of P. eryngii such as Pe-1 (native to Bangladesh), Pe-2 (germplasm collected from China) and Pe-3 (germplasm collected from Japan) were cultivated on saw dust and rice straw and their growth and yield parameters were investigated. Pe-1 on saw dust showed the highest biological yield and efficiency (73.5%) than other strains. Also, the mycelium run rate and number of fruiting bodies were higher in Pe-1 than other two strains. The quality of mushroom strains was near about similar. On saw dust, the yield and efficiency were better than those cultivated on rice straw, however, on straw; the mushroom fruiting bodies were larger in size. This study shows the prospects of P. eryngii cultivation in Bangladesh and suggests further study in controlled environment for higher yield and production.

Radiation pre-treating straw hydrolyzed by cellulase resulted from immobilized Trichoderma reesei growing cells

International Nuclear Information System (INIS)

Lu Zhaoxin; Minoru Kumakura

1992-01-01

Wheat and rice straw was irradiated by electron beam with different dose at the presence of 4% NaOH or without 4% NaOH. The powder fraction above 200 meshes in pretreated rice straw increased with increasing doses and it was more at presence of 4% NaOH than that without 4% NaOH. The pretreated straw was hydrolyzed with 1% cellulase at 40 degree C for 48 h. The glucose yield (%) was given a rise with the increase of irradiation dose and it was 70% and 80% over that of un-pretreated rice and wheat straw, respectively. At the presence of 4% NaOH, the glucose yield increased as the irradiation dose increased from 0 to 5 x 10 5 Gy, reaching a maximum, 35% for wheat straw and 36.6% for rice straw, which increased by about 2.5 times in comparison with un-pretreated straw, then decrease with increasing the irradiation dose to 10 x 10 5 Gy. The glucose yield reached 19% and 22% for rice and wheat straw in 6 days of hydrolysis, respectively

Comparing the Bio-Hydrogen Production Potential of Pretreated Rice Straw Co-Digested with Seeded Sludge Using an Anaerobic Bioreactor under Mesophilic Thermophilic Conditions

Directory of Open Access Journals (Sweden)

Asma Sattar

2016-03-01

Full Text Available Three common pretreatments (mechanical, steam explosion and chemical used to enhance the biodegradability of rice straw were compared on the basis of bio-hydrogen production potential while co-digesting rice straw with sludge under mesophilic (37 °C and thermophilic (55 °C temperatures. The results showed that the solid state NaOH pretreatment returned the highest experimental reduction of LCH (lignin, cellulose and hemi-cellulose content and bio-hydrogen production from rice straw. The increase in incubation temperature from 37 °C to 55 °C increased the bio-hydrogen yield, and the highest experimental yield of 60.6 mL/g VSremoved was obtained under chemical pretreatment at 55 °C. The time required for maximum bio-hydrogen production was found on the basis of kinetic parameters as 36 h–47 h of incubation, which can be used as a hydraulic retention time for continuous bio-hydrogen production from rice straw. The optimum pH range of bio-hydrogen production was observed to be 6.7 ± 0.1–5.8 ± 0.1 and 7.1 ± 0.1–5.8 ± 0.1 under mesophilic and thermophilic conditions, respectively. The increase in temperature was found useful for controlling the volatile fatty acids (VFA under mechanical and steam explosion pretreatments. The comparison of pretreatment methods under the same set of experimental conditions in the present study provided a baseline for future research in order to select an appropriate pretreatment method.

Soil to rice transfer factors for 226Ra, 228Ra, 210Pb, 40K and 137Cs: a study on rice grown in India

International Nuclear Information System (INIS)

Karunakara, N.; Rao, Chetan; Ujwal, P.; Yashodhara, I.; Kumara, Sudeep; Ravi, P.M.

2013-01-01

were determined under natural field conditions of West Coast of India. ► The mean values of soil to white rice transfer factors were 1.8 × 10 −1 , 4.2 × 10 −3 , 3.0 × 10 −2 for 40 K, 210 Pb, and 137 Cs, respectively. ► 40 K transfer factor for straw was significantly higher than those of grain and root. ► 210 Pb and 137 Cs was retained in the roots of rice plants and its transfer to above the ground organs is lower. ► The radionuclide concentrations in plant were not linearly related to soil concentration

Inhibitory effects of phenolic compounds of rice straw formed by saccharification during ethanol fermentation by Pichia stipitis.

Science.gov (United States)

Wang, Xiahui; Tsang, Yiu Fai; Li, Yuhao; Ma, Xiubing; Cui, Shouqing; Zhang, Tian-Ao; Hu, Jiajun; Gao, Min-Tian

2017-11-01

In this study, it was found that the type of phenolic acids derived from rice straw was the major factor affecting ethanol fermentation by Pichia stipitis. The aim of this study was to investigate the inhibitory effect of phenolic acids on ethanol fermentation with rice straw. Different cellulases produced different ratios of free phenolic acids to soluble conjugated phenolic acids, resulting in different fermentation efficiencies. Free phenolic acids exhibited much higher inhibitory effect than conjugated phenolic acids. The flow cytometry results indicated that the damage to cell membranes was the primary mechanism of inhibition of ethanol fermentation by phenolic acids. The removal of free phenolic acids from the hydrolysates increased ethanol productivity by 2.0-fold, indicating that the free phenolic acids would be the major inhibitors formed during saccharification. The integrated process for ethanol and phenolic acids may constitute a new strategy for the production of low-cost ethanol. Copyright © 2017 Elsevier Ltd. All rights reserved.

Study on the Potential of Rice Straws as a Supplementary Fuel in Very Small Power Plants in Thailand

OpenAIRE

Penwadee Cheewaphongphan; Agapol Junpen; Orachorn Kamnoet; Savitri Garivait

2018-01-01

Agricultural residue is a major raw material for renewable energy production, particularly heat production, in Thailand. Meanwhile, the process-based residue, such as bagasse, rice husk, wood residue, palm fiber, palm shell, and saw dust, is used as a fuel for energy production in the agro-industry. Hence, this study is intended to assess the net potential and capacity of alternative agricultural residues, specifically rice straws, to serve as the supplementary fuel for very small power plant...

Differences in net global warming potential and greenhouse gas intensity between major rice-based cropping systems in China

Science.gov (United States)

Xiong, Zhengqin; Liu, Yinglie; Wu, Zhen; Zhang, Xiaolin; Liu, Pingli; Huang, Taiqing

2015-01-01

Double rice (DR) and upland crop-single rice (UR) systems are the major rice-based cropping systems in China, yet differences in net global warming potential (NGWP) and greenhouse gas intensity (GHGI) between the two systems are poorly documented. Accordingly, a 3-year field experiment was conducted to simultaneously measure methane (CH4) and nitrous oxide (N2O) emissions and changes in soil organic carbon (SOC) in oil rape-rice-rice and wheat-rice (representing DR and UR, respectively) systems with straw incorporation (0, 3 and 6 t/ha) during the rice-growing seasons. Compared with the UR system, the annual CH4, N2O, grain yield and NGWP were significantly increased in the DR system, though little effect on SOC sequestration or GHGI was observed without straw incorporation. Straw incorporation increased CH4 emission and SOC sequestration but had no significant effect on N2O emission in both systems. Averaged over the three study years, straw incorporation had no significant effect on NGWP and GHGI in the UR system, whereas these parameters were greatly increased in the DR system, i.e., by 108% (3 t/ha) and 180% (6 t/ha) for NGWP and 103% (3 t/ha) and 168% (6 t/ha) for GHGI. PMID:26626733

Differences in net global warming potential and greenhouse gas intensity between major rice-based cropping systems in China.

Science.gov (United States)

Xiong, Zhengqin; Liu, Yinglie; Wu, Zhen; Zhang, Xiaolin; Liu, Pingli; Huang, Taiqing

2015-12-02

Double rice (DR) and upland crop-single rice (UR) systems are the major rice-based cropping systems in China, yet differences in net global warming potential (NGWP) and greenhouse gas intensity (GHGI) between the two systems are poorly documented. Accordingly, a 3-year field experiment was conducted to simultaneously measure methane (CH4) and nitrous oxide (N2O) emissions and changes in soil organic carbon (SOC) in oil rape-rice-rice and wheat-rice (representing DR and UR, respectively) systems with straw incorporation (0, 3 and 6 t/ha) during the rice-growing seasons. Compared with the UR system, the annual CH4, N2O, grain yield and NGWP were significantly increased in the DR system, though little effect on SOC sequestration or GHGI was observed without straw incorporation. Straw incorporation increased CH4 emission and SOC sequestration but had no significant effect on N2O emission in both systems. Averaged over the three study years, straw incorporation had no significant effect on NGWP and GHGI in the UR system, whereas these parameters were greatly increased in the DR system, i.e., by 108% (3 t/ha) and 180% (6 t/ha) for NGWP and 103% (3 t/ha) and 168% (6 t/ha) for GHGI.

Mass loss and chemical structures of wheat and maize straws in response to ultraviolet-B radiation and soil contact

Science.gov (United States)

Zhou, Guixiang; Zhang, Jiabao; Mao, Jingdong; Zhang, Congzhi; Chen, Lin; Xin, Xiuli; Zhao, Bingzi

2015-01-01

The role of photodegradation, an abiotic process, has been largely overlooked during straw decomposition in mesic ecosystems. We investigated the mass loss and chemical structures of straw decomposition in response to elevated UV-B radiation with or without soil contact over a 12-month litterbag experiment. Wheat and maize straw samples with and without soil contact were exposed to three radiation levels: a no-sunlight control, ambient solar UV-B, and artificially elevated UV-B radiation. A block control with soil contact was not included. Compared with the no-sunlight control, UV-B radiation increased the mass loss by 14–19% and the ambient radiation by 9–16% for wheat and maize straws without soil contact after 12 months. Elevated UV-B exposure decreased the decomposition rates of both wheat and maize straws when in contact with soil. Light exposure resulted in decreased O-alkyl carbons and increased alkyl carbons for both the wheat and maize straws compared with no-sunlight control. The difference in soil contact may influence the contribution of photodegradation to the overall straw decomposition process. These results indicate that we must take into account the effects of photodegradation when explaining the mechanisms of straw decomposition in mesic ecosystems. PMID:26423726

Mass loss and chemical structures of wheat and maize straws in response to ultraviolet-B radiation and soil contact.

Science.gov (United States)

Zhou, Guixiang; Zhang, Jiabao; Mao, Jingdong; Zhang, Congzhi; Chen, Lin; Xin, Xiuli; Zhao, Bingzi

2015-10-01

The role of photodegradation, an abiotic process, has been largely overlooked during straw decomposition in mesic ecosystems. We investigated the mass loss and chemical structures of straw decomposition in response to elevated UV-B radiation with or without soil contact over a 12-month litterbag experiment. Wheat and maize straw samples with and without soil contact were exposed to three radiation levels: a no-sunlight control, ambient solar UV-B, and artificially elevated UV-B radiation. A block control with soil contact was not included. Compared with the no-sunlight control, UV-B radiation increased the mass loss by 14-19% and the ambient radiation by 9-16% for wheat and maize straws without soil contact after 12 months. Elevated UV-B exposure decreased the decomposition rates of both wheat and maize straws when in contact with soil. Light exposure resulted in decreased O-alkyl carbons and increased alkyl carbons for both the wheat and maize straws compared with no-sunlight control. The difference in soil contact may influence the contribution of photodegradation to the overall straw decomposition process. These results indicate that we must take into account the effects of photodegradation when explaining the mechanisms of straw decomposition in mesic ecosystems.

Stabilization of organic matter in the raised-bed soils of tidal swamplands is influenced by the types and the amounts of organic matter application

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A R Saidy

2015-05-01

Full Text Available Farmers in tidal swamplands annually added organic matter (OM onto the raised beds to maintain organic matter contents and thereby maintain soil productivity of the raised beds. This experiment aimed to study the influence of the types and the amounts of OM on the stabilization of organic matter in the raised-bed soils. Four types of OM: rice straw, eceng gondok (Eichornia crassipes, purun tikus  (Eleocharis dulcis and mixed  rice straw-eceng gondok were added to a 27-year raised bed soil with 4 different rates: 0, 0.5, 1.0 and 2.0  of maximum sorption capacity (Qmax, and the OM stabilization was quantified after 10 weeks of OM addition.  Results of this study showed with the exception of rice straw, OM addition to soil resulted in increases in the mineralization of soil OM thereby inducing priming effect. Addition of rice straw at rate of 0.5 of Qmax resulted in stabilization of 46% added OM, while only 30% and 37% of added OM was stabilized when OM was added to soils at rates of 1.0 and 2.0 Qmax, respectively.  This study showed that the stabilization of OM in raised bed soils were influenced by the chemical composition of OM and the amount of added OM.

Stabilization of organic matter in the raised-bed soils of tidal swamplands is influenced by the types and the amounts of organic matter application

Directory of Open Access Journals (Sweden)

A R Saidy

2015-03-01

Full Text Available Farmers in tidal swamplands annually added organic matter (OM onto the raised beds to maintain organic matter contents and thereby maintain soil productivity of the raised beds. This experiment aimed to study the influence of the types and the amounts of OM on the stabilization of organic matter in the raised-bed soils. Four types of OM: rice straw, eceng gondok (Eichornia crassipes, purun tikus  (Eleocharis dulcis and mixed  rice straw-eceng gondok were added to a 27-year raised bed soil with 4 different rates: 0, 0.5, 1.0 and 2.0  of maximum sorption capacity (Qmax, and the OM stabilization was quantified after 10 weeks of OM addition.  Results of this study showed with the exception of rice straw, OM addition to soil resulted in increases in the mineralization of soil OM thereby inducing priming effect. Addition of rice straw at rate of 0.5 of Qmax resulted in stabilization of 46% added OM, while only 30% and 37% of added OM was stabilized when OM was added to soils at rates of 1.0 and 2.0 Qmax, respectively.  This study showed that the stabilization of OM in raised bed soils were influenced by the chemical composition of OM and the amount of added OM.

Co-pyrolysis of rice straw and Polyethylene Terephthalate (PET) using a fixed bed drop type pyrolyzer

Science.gov (United States)

Izzatie, N. I.; Basha, M. H.; Uemura, Y.; Hashim, M. S. M.; Amin, N. A. M.; Hamid, M. F.

2017-10-01

In this work, co-pyrolysis of rice straw and polyethylene terephthalate (PET) was carried out at different temperatures (450,500,550, and 600°C) at ratio 1:1 by using fixed bed drop-type pyrolyzer. The purpose of this work is to determine the effect of pyrolysis temperature on the product yield. As the temperature increased, the pyrolysis oil increased until it reaches certain high temperature (600°C), the pyrolysis oil decreased as of more NCG were produced. The temperature 550°C is considered as the optimum pyrolysis temperature since it produced the highest amount of pyrolysis oil with 36 wt.%. In pyrolysis oil, the calorific value (13.98kJ/g) was low because of the presence of high water content (52.46 wt.%). Main chemicals group from pyrolysis oil were an aldehyde, ketones, acids, aromatics, and phenol and all compound have abundant of hydrogen and carbon were identified. Co-pyrolysis of rice straw and PET produced a higher amount of carbon oxides and recycling back the NCG could increase liquid and char yields.

Bed agglomeration in fluidized combustor fueled by wood and rice straw blends

DEFF Research Database (Denmark)

Thy, Peter; Jenkins, Brian; Williams, R.B.

2010-01-01

Abstract Petrographic techniques have been used to examine bed materials from fluidized bed combustion experiments that utilized wood and rice straw fuel blends. The experiments were conducted using a laboratory-scale combustor with mullite sand beds, firing temperatures of 840 to 1030 °C, and run...... areas between bed particles, ultimately led to bed agglomeration. The interfaces and the presence of gas bubbles in the cement suggest a bonding material with a high surface tension and a liquid state. The cement films originate by filling of irregularities on individual and partially agglomerated bed...

Metabolism of 14C-lindane in flooded alluvial soil

International Nuclear Information System (INIS)

Siddaramappa, R.; Sethunathan, N.

1975-01-01

The effect of rice straw on the persistence of uniformly ring labelled 14 C-lindane in an alluvial soil was investigated under flooded conditions. The residues in the soil were extracted with chloroform-diethyl ether and the radioactivity was measured by liquid scintillation. The radioactivity in the solvent phase decreased more rapidly in amended soil than in unamended soil. Radioautograph of thin layer chromatograms of solvent phase indicated that lindane was readily converted to a breakdown product in both amended and unamended soils. This breakdown product was also formed in both autoclaved and nonautoclaved soils. Rice straw amendment enhanced further decomposition of lindane and its breakdown product. Heat treatment retarded further decomposition of lindane and its breakdown product whereas they were rapidly decomposed in nonautoclaved soil. These studies indicated that in flooded alluvial soil tested, lindane was initially decomposed by a chemical reaction and soil microorganisms appeared to attack the products of the chemical reaction. (author)

Effects of Soil Veterinary Antibiotics Pollution on Rice Growth

Directory of Open Access Journals (Sweden)

XU Qiu-tong

2016-01-01

Full Text Available To understand the potential effect of soil veterinary antibiotics pollution on the growth of rice, a main food crop in China, oxytetracycline which was used widely in livestock and poultry breeding was selected to test the effects of different levels of soil antibiotics pollution on growth and yield of rice plant at both seedling and growth periods. Relationship between oxytetracycline accumulated in different organs of rice plant and oxytetracycline pollution levels in the soil was characterized. The results showed that the effects of soil oxytetracycline pollution on rice growth mainly occurred at the seedling stage, and the effect on the underground part was obviously greater than the above-ground part of rice. Significant negative effects on biomass of the underground part of rice, root activity, and chlorophyll content and oxidase activity of the leave at the seedling stage were found when soil oxytetracycline pollution concentrations was over 30 mg·kg-1. The consequence from the impact of soil oxytetracycline pollution on rice seedling could be extended to the whole growth period of the plant, which could reduce the number of tiller and rice yield. Oxytetracycline accumulated in various organs of rice plant was in the sequence of root> leaf> stem> grain. Rice roots had low capacity to uptake oxytetracycline from the soil, the transfer capacity of oxytetracycline from the roots to leaf, stem, and grain was also weak. Considering the low oxytetracycline pollution levels in most of current actual farmland soils (less than 10 mg·kg-1 and lower accumulation character of oxytetracycline in the grain, it is thought that the direct damage of soil oxytetracycline pollution on rice production is small.

Anaerobic detoxification fermentation by Rhodospirillum rubrum for rice straw as feed with moderate pretreatment.