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Deng W.,Hainan University | van Zwieten L.,Australian Department of Primary Industries and Fisheries | Lin Z.,Chinese Academy of Sciences | Liu X.,Guangdong Dazhong Agriculture Science Co. | And 4 more authors.
Journal of Soils and Sediments | Year: 2016

Purpose: A paucity in knowledge remains on the influence of biochar production temperature and the rate of application on greenhouse gas emissions from soil. The objective of this column experiment was to evaluate a biochar thermosequence by doses on CO2, N2O, and CH4 emissions from a latosol following nitrogen fertilizer application following a pre-incubation period. Materials and methods: Biochar was produced from sugarcane bagasse pyrolyzed at 300, 500, and 700 °C (BC 300, BC 500, and BC 700, respectively). Biochars were added to air-dried latosol columns at rates of 0, 0.5, 1, 2, 5, 10, and 15 % (w/w), and the water content was brought to 95 % of water-filled pore space (WFPS). The emissions from columns were tested on days 1, 3, 7, 15, and 30 following a 30-day pre-incubation. Results and discussion: All treatments showed a decrease in respiration across the study period. The higher doses of biochar of BC 300 and BC 700 resulted in significantly higher respiration than controls on days 15 and 30. Neither biochar dose nor temperature had a significant effect on CH4 emissions during the study period. Application of all biochars suppressed the emissions of N2O at all doses on days 1 and 3, compared to the control. N2O emissions from higher temperature biochar-amended soil at 2, 5, 10, and 15 % were greater than that from corresponding treatments of lower-temperature biochar-amended soil on days 15 and 30. Conclusions: Soil respiration and overall greenhouse gas emission from latosol increased with biochar dose and pyrolysis temperature in the 30-day study period due to increasing water retention facilitated by biochar. Careful consideration is needed when applying bagasse biochar as it changes N cycling and soil physical properties. © 2016 Springer-Verlag Berlin Heidelberg


PubMed | University of Bremen, The New Zealand Institute for Plant and Food Research Ltd, CAS Institute of High Energy Physics, Hainan University and 3 more.
Type: | Journal: The Science of the total environment | Year: 2016

In this study, we examined the efficacy of nine different types of coconut-fiber derived biochars (CFBs), prepared at different temperatures and chemically modified with ammonia, hydrogen peroxide and nitric acid, to remove lead (Pb


Yang X.,Zhejiang University | Liu J.,Zhejiang University | McGrouther K.,Scion Research | Huang H.,Bijie Yancao Company of Guizhou Province | And 8 more authors.
Environmental Science and Pollution Research | Year: 2016

Biochar is a carbon-rich solid material derived from the pyrolysis of agricultural and forest residual biomass. Previous studies have shown that biochar is suitable as an adsorbent for soil contaminants such as heavy metals and consequently reduces their bioavailability. However, the long-term effect of different biochars on metal extractability or soil health has not been assessed. Therefore, a 1-year incubation experiment was carried out to investigate the effect of biochar produced from bamboo and rice straw (at temperatures ≥500 °C) on the heavy metal (cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn)) extractability and enzyme activity (urease, catalase, and acid phosphatase) in a contaminated sandy loam paddy soil. Three rates (0, 1, and 5 %) and two mesh sizes (<0.25 and <1 mm) of biochar applications were investigated. After incubation, the physicochemical properties, extractable heavy metals, available phosphorus, and enzyme activity of soil samples were analyzed. The results demonstrated that rice straw biochar significantly (P < 0.05) increased the pH, electrical conductivity, and cation exchange capacity of the soil, especially at the 5 % application rate. Both bamboo and rice straw biochar significantly (P < 0.05) decreased the concentration of CaCl2-extractable heavy metals as biochar application rate increased. The heavy metal extractability was significantly (P < 0.01) correlated with pH, water-soluble organic carbon, and available phosphorus in soil. The 5 % application rate of fine rice straw biochar resulted in the greatest reductions of extractable Cu and Zn, 97.3 and 62.2 %, respectively. Both bamboo and rice straw biochar were more effective at decreasing extractable Cu and Pb than removing extractable Cd and Zn from the soil. Urease activity increased by 143 and 107 % after the addition of 5 % coarse and fine rice straw biochars, respectively. Both bamboo and rice straw biochars significantly (P < 0.05) increased catalase activity but had no significant impact on acid phosphatase activity. In conclusion, the rice straw biochar had greater potential as an amendment for reducing the bioavailability of heavy metals in soil than that of the bamboo biochar. The impact of biochar treatment on heavy metal extractability and enzyme activity varied with the biochar type, application rate, and particle size. © 2015, Springer-Verlag Berlin Heidelberg.


PubMed | University of South Australia, Zhejiang Agriculture And forestry University, La Trobe University, Zhejiang University and 2 more.
Type: | Journal: Chemosphere | Year: 2015

Biochar is a carbonaceous sorbent and can be used as a potential material to reduce the bioavailability of organic pollutants in contaminated soils. In the present study, the adsorption and desorption of diethyl phthalate (DEP) onto soils amended with bamboo biochar was investigated with a special focus on the effect of biochar application rates and aging conditions on the adsorption capacity of the soils. Biochar amendment significantly enhanced the soil adsorption of DEP that increased with increasing application rates of biochar. However, the adsorption capacity decreased by two aging processes (alternating wet and dry, and constantly moist). In the soil with low organic carbon (OC) content, the addition of 0.5% biochar (without aging) increased the adsorption by nearly 98 times compared to the control, and exhibited the highest adsorption capacity among all the treatments. In the soil with high OC content, the adsorption capacity in the treatment of 0.5% biochar without aging was 3.5 and 3 times greater than those of the treatments of biochar aged by alternating wet and dry, and constantly moist, respectively. Moreover, constantly moist resulted in a greater adsorption capacity than alternating wet and dry treatments regardless of biochar addition. This study revealed that biochar application enhanced soil sorption of DEP, however, the enhancement of the adsorption capacity was dependent on the soil organic carbon levels, and aging processes of biochar.


PubMed | Scion Research, Bijie Yancao Company of Guizhou Province, Guangdong Dazhong Agriculture Science Co. and Zhejiang University
Type: Journal Article | Journal: Environmental science and pollution research international | Year: 2016

Biochar is a carbon-rich solid material derived from the pyrolysis of agricultural and forest residual biomass. Previous studies have shown that biochar is suitable as an adsorbent for soil contaminants such as heavy metals and consequently reduces their bioavailability. However, the long-term effect of different biochars on metal extractability or soil health has not been assessed. Therefore, a 1-year incubation experiment was carried out to investigate the effect of biochar produced from bamboo and rice straw (at temperatures 500 C) on the heavy metal (cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn)) extractability and enzyme activity (urease, catalase, and acid phosphatase) in a contaminated sandy loam paddy soil. Three rates (0, 1, and 5%) and two mesh sizes (<0.25 and <1 mm) of biochar applications were investigated. After incubation, the physicochemical properties, extractable heavy metals, available phosphorus, and enzyme activity of soil samples were analyzed. The results demonstrated that rice straw biochar significantly (P<0.05) increased the pH, electrical conductivity, and cation exchange capacity of the soil, especially at the 5% application rate. Both bamboo and rice straw biochar significantly (P<0.05) decreased the concentration of CaCl2-extractable heavy metals as biochar application rate increased. The heavy metal extractability was significantly (P<0.01) correlated with pH, water-soluble organic carbon, and available phosphorus in soil. The 5% application rate of fine rice straw biochar resulted in the greatest reductions of extractable Cu and Zn, 97.3 and 62.2%, respectively. Both bamboo and rice straw biochar were more effective at decreasing extractable Cu and Pb than removing extractable Cd and Zn from the soil. Urease activity increased by 143 and 107% after the addition of 5% coarse and fine rice straw biochars, respectively. Both bamboo and rice straw biochars significantly (P<0.05) increased catalase activity but had no significant impact on acid phosphatase activity. In conclusion, the rice straw biochar had greater potential as an amendment for reducing the bioavailability of heavy metals in soil than that of the bamboo biochar. The impact of biochar treatment on heavy metal extractability and enzyme activity varied with the biochar type, application rate, and particle size.


PubMed | University of Newcastle, Scion Research, Zhejiang University, Kangwon National University and 3 more.
Type: Journal Article | Journal: Journal of environmental management | Year: 2016

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 (<0.25mm and <1mm), were applied at three rates (0, 1, and 5% w/w). Heavy metal concentrations in pore water were determined after extraction with 0.01M CaCl


Lu T.,Hangzhou Dianzi University | Liu X.,Guangdong Dazhong Agriculture Science Co. | Qi D.,Zhejiang Sci-Tech University | Zhao H.,Hangzhou Dianzi University
Iranian Polymer Journal (English Edition) | Year: 2015

Aqueous dispersion polymerization has been considered as a promising green technology for preparing water-soluble polymers such as cationic polyacrylamide (CPAM). Dispersion copolymerization of acrylamide and 2-methylacryloylxyethyl trimethyl ammonium chloride was generally carried out in aqueous ammonium sulfate solution with poly(2-methylacryloylxyethyl trimethyl ammonium chloride) as the stabilizer. In this study, we reported the potential influence of a small amount of hydrophobic monomer, methyl methacrylate (MMA), on the above-mentioned aqueous dispersion polymerization system. It was found that MMA could play an important role in the polymerization process by significantly affecting the particle formation and stabilization, as well as the viscosity evolution of the reaction mixture during polymerization. With the addition of a small amount of MMA, the particle formation was accelerated and the viscosity of the polymerization system decreased significantly. With the increase in MMA addition, the final copolymer particle size was reduced and its size distribution became narrower; meanwhile, the particle morphology tended to be spherical. Moreover, it was found that the addition of MMA could favor the production of CPAM with high charge density. The flocculation performance of the resulting CPAM dispersion was also examined in detail and it was found that the introduction of MMA unit into CPAM molecular chain could improve its flocculation efficiency. © 2015, Iran Polymer and Petrochemical Institute.


Patent
Guangdong Dazhong Agriculture Science Co. | Date: 2013-12-10

A toothpaste type fertilizer, which includes a toothpaste casing and paste fertilizer contained in the toothpaste casing. The toothpaste type fertilizer breaks a traditional fertilizer split charging mode, and the fertilizer is contained in the toothpaste casing to enable a package of the fertilizer to tend to miniaturization and facilitation, which avoids troublesome caused by buying large-package fertilizer and brings conveniences for to a plant culturist in an urban family; when in use, squeezing out the fertilizer in a needed amount like squeezing toothpaste is only required; after completion of use, the fertilizer is easy to save and store, and no taste of the fertilizer is spilled out. The toothpaste type fertilizer can serve as a fast-moving consumer goods appeared in various shopping malls and supermarkets, and can further serve as a gift for presenting relatives and friends.


PubMed | Zhejiang Agriculture And forestry University, Guangdong Dazhong Agriculture Science Co., The New Zealand Institute for Plant and Food Research Ltd and Zhejiang University
Type: | Journal: Chemosphere | Year: 2015

A pot experiment was conducted to evaluate the effect of biochars on the bioavailability of di-(2-ethylhexyl) phthalate (DEHP) in two soils using Brassica chinensis L. as an indicator plant. The residual concentrations of DEHP tended to be higher in the biochar-amended soils than in the control soils. They were lower (p<0.05) in the high organic carbon content soil (HOC; 2.2%C) than in the low organic carbon content soil (LOC; 0.35%C). The DEHP concentrations in plant shoots grown in the HOC soils were lower than those in the LOC soils (p<0.05). Compared to the control, the biochar addition decreased the DEHP concentrations in shoots grown in the LOC soils; whereas there was no significant difference in the HOC soils. Our results showed that soil OC content as well as biochar properties are the key factors influencing the bioavailability of DEHP in soils.


Patent
Guangdong Dazhong Agriculture Science Co. | Date: 2014-07-02

A toothpaste type fertilizer, which includes a toothpaste casing (1) and paste fertilizer (2) contained in the toothpaste casing (1). The toothpaste type fertilizer breaks a traditional fertilizer split charging mode, and the fertilizer is contained in the toothpaste casing (1) to enable a package of the fertilizer to tend to miniaturization and facilitation, which avoids troublesome caused by buying large-package fertilizer and brings conveniences for to a plant culturist in an urban family; when in use, squeezing out the fertilizer in a needed amount like squeezing toothpaste is only required; after completion of use, the fertilizer is easy to save and store, and no taste of the fertilizer is spilled out. The toothpaste type fertilizer can serve as a fast-moving consumer goods appeared in various shopping malls and supermarkets, and can further serve as a gift for presenting relatives and friends.

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