Cow Manure Biochar Research Articles

Influence of pyrolysis temperature on chemical speciation, leaching ability, and environmental risk of heavy metals in biochar derived from cow manure

This study analyzed the chemical speciation, leaching ability, and environmental risk of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) in cow manure biochar (CMBC) pyrolyzed at various temperatures. The total content, chemical speciation, and leaching ability of the heavy metals were determined through microwave digestion, modified BCR three-step sequential extraction procedure, and leaching solution systems (TCLP, distilled water, and SPLP). The risk assessment code, Muller geo-accumulation index, potential ecological risk index, and germination index were used to evaluate the environmental safety and ecotoxicity of heavy metals. Significant differences were observed in the physicochemical properties of CMBCs. The heavy metal contents in CMBCs were higher than those in CM. The bioavailable fraction of heavy metals was transformed into a relatively stable fraction with increasing pyrolysis temperature. Furthermore, the potential risks and ecotoxicity of biochar were reduced, thus improving environmental safety. The study results provide important data for biochar applications.

Combining the phosphate solubilizing microorganisms with biochar types in order to improve safflower yield and soil enzyme activity

ABSTRACT Soil amendment with biochar could increase soil microbial activity and biomass. This study contributes to an understanding of the synergistic effects of biochar and phosphate solubilizing microorganisms on safflower yield and soil microbial activity enhancement. In the split plot experiments that repeated in two years, the main factor was biochar types included cow manure, wheat straw, wood biochar and control. The sub factors were phosphate solubilizing microorganisms included the mycorrhizal fungi (Glomus etunicatum and G. mosseae), Bacillus lentus, Pseudomonas fluorescence and control. The highest levels of dehydrogenase, urease activity and microbial biomass carbon were obtained from the cow manure biochar. The maximum activity of acid phosphatase was in the plots inoculated by P. fluorescence in all treatments, whether using or not using biochar. The grain yield of plants inoculated with B. lentus and P. fluorescence was in the same statistical group. The highest grain yield equal to 1527 kg/ha was obtained when using cow manure biochar. According to the results, the application of cow manure biochar and phosphate solubilizing microorganisms, especially mycorrhiza species, can be recommended for improving soil biological traits and safflower yield traits.

Application of biochars and solid fraction of digestate to decrease soil solution Cd, Pb and Zn concentrations in contaminated sandy soils.

Biochar prepared from waste biomass was evaluated as a soil amendment to immobilize metals in two contaminated soils. A 60-day incubation experiment was set up on a French technosol which was heavily contaminated with Pb due to former mining activities. Grass biochar, cow manure biochar (CMB) and two lightwood biochars differing in particle size distribution (LWB1 and LWB2) were amended to the soil at a rate of 2% (by mass). Rhizon soil moisture samplers were employed to assess the Pb concentrations in the soil solution at regular times. After 30days of incubation, soil solution concentrations in the CMB-amended soil decreased by more than 99% compared to the control. CMB was also applied to a moderately contaminated Flemish soil and resulted in lowered soil solution Cd and Zn concentrations. While the application of 4% CMB resulted in 90% and 80% reductions in soil solution concentrations of Cd and Zn, respectively, the solid fraction of digestate (as a reference) reduced the soil pore water concentrations by only 63% for Cd and 73% for Zn, compared to the concentrations in the control. These results emphasize the potential of biochar to immobilize metals in soil and water systems, thus reducing their phytotoxicity.

Effects of humic acid and cow manure biochar (CMB) in culture medium on growth and mineral concentrations of basil plant.

In sustainable agriculture, protection of the ecosystem and reduce chemical fertilizers are the main goals. Nowadays, sweet basil, one of the best general fragrant foliage, is considered as an industrial plant. In present study to compare different levels of cow manure biochar (CMB) and humic acid (HA) on vegetative traits and mineral absorption rate of green basil plants, an experiment was conducted based on a completely randomized block design with four replications in 2015. The treatments included different levels of CMB (0, 1%, 2%, and 3%) and HA (2.5, 5 and 7.5 g/L) in the culture medium. The traits that were analyzed were included: plant height, leaf number, leaf area, stem diameter, leaf chlorophyll concentration (LCC), fresh and dry weights of aerial part and root, concentration of potassium, nitrogen, calcium and phosphorus. Results showed that fresh and dry weights of shoot and root were increased by application of 3% CMB and 7.5 g/L HA in the culture medium. Theuse of CMB and HA significantly affected most of the studied traits except LCC, stem diameter, and leaf area. Concentration of N, P, K and Ca was considerably increased by application of 3% CMB and 7.5 g/L HA in the culture medium. The highest concentration of nutrients was detected in the plants treated with 3% CMB. In conclusion, the use of 3% CMB and HA at 7.5 g/L in the culture medium can be recommended to improve the qualitative and quantitative traits of basil plants.

Characteristics of tetracycline adsorption by cow manure biochar prepared at different pyrolysis temperatures

This study aimed to explore the feasibility of using cow manure biochar (CMBC) for adsorption of tetracycline for realizing farm waste treatment and recycling. Three kinds of pyrolysis-temperature CMBCs were prepared and characterized. There were significant differences in the specific surface area, pores structure, surface charge, and oxygen-containing functional groups. The effect of adsorption was not only related to the physicochemical properties of CMBC but also the dosage, solution pH, and ambient temperature. CMBC showed surface heterogeneity, and the adsorption of tetracycline was mainly chemical. Controlling the rate of adsorption was achieved by combining internal particle diffusion and liquid film diffusion. Furthermore, the adsorption was a spontaneous and endothermic process. The use of CMBC as an adsorbent for tetracycline represents a new method for treating and recycling waste in farms. These results could aid in further studies on the adsorption mechanism and optimizing the adsorption process.

Effect of cow manure biochar on heavy metals uptake and translocation by zucchini (Cucurbita pepo L)

Little is known about the efficiency of biochar in the safety of food production in arid and semiarid contaminated soils. A field experiment in the semiarid region of Upper Egypt was conducted to explore heavy metals uptake by zucchini (Cucurbita pepo L) plants as affected by the application of cow manure biochar (CMB). Three rates of CMB were added, i. e., 0, 4, and 8 tonnes ha−1. The roots and shoots of zucchini plants stored 75 and 78% of Zn and Cu, respectively, while 25 and 22% were transported to the edible portions. On the other hand, the roots and shoots of zucchini plants stored more than 99% of Pb and Cd, while less than 1% was transported to the edible portions. Cow manure biochar (CMB) minimized the values of bioaccumulation factor (BAC) for Zn, Cd, and Ni by 5.6, 21.9, and 27.9%, respectively, while these reductions in the case of translocation factor (TF) were 4.9, 7.5, 23, and 5.9%. Cow manure biochar at a rate of 4 tonnes ha−1 reduced the availability of Zn, Cu, Pb, Cd, and Ni by 13.3, 8.3, 13.8, 9.1, and 3.6%, respectively, compared to the control treatment. Cow manure biochar at a rate of 8 tonnes minimized Zn, Cu, Pb, Cd, and Ni concentrations in the edible parts of zucchini plants by 10, 17, 66, 20, and 26%, respectively, in comparison with the untreated soil. Biochar reduced the heavy metals bioavailability, moreover; biochar minimized the soil-root transfer and the root-shoot of toxic metals. It is recommended to add cow manure biochar to zucchini plants to reduce the accumulating of hazard metals in the edible tissues.

Impact of mineral components in cow manure biochars on the adsorption and competitive adsorption of oxytetracycline and carbaryl

Knowledge about the impact of mineral component in biochar on the sorption of OTC and CBL is limited and need be systematically studied. The mineral component of cow manure biochar showed different effects on the sorption of OTC and CBL.

Effects of biochar and alkaline amendments on cadmium immobilization, selected nutrient and cadmium concentrations of lettuce (Lactuca sativa) in two contrasting soils.

To assess the efficiency of seven treatments including biochars produced from dried faecal matter and manures as stabilizing agents of cadmium (Cd)-spiked soils, lettuce was grown in glasshouse on two contrasting soils. The soils used were moderately fertile silty loam and less fertile sandy loam and the applied treatments were 7 % w/w. The reduction of bioavailable Cd (ammonium nitrate extractable) and its phytoavailability for lettuce were used as assessment criteria in the evaluation of stabilization performance of each treatment. Moreover, the agronomic values of the treatments were also investigated. Ammonium nitrate extraction results indicated that faecal matter biochar, cow manure biochar and lime significantly reduced bioavailable Cd by 84–87, 65–68 and 82–91 %, respectively, as compared to the spiked controls. Unpredictably, coffee husk biochar induced significant increment of Cd in NH4NO3 extracts. The immobilization potential of faecal matter biochar and lime were superior than the other treatments. However, lime and egg shell promoted statistically lower yield and P, K and Zn concentrations response of lettuce plants compared to the biochar treatments. The lowest Cd and highest P tissue concentrations of lettuce plants were induced by faecal matter and cow manure biochar treatments in both soils. Additionally, the greatest Cd phytoavailability reduction for lettuce was induced by poultry litter and cow manure biochars in the silty loam soil. Our results indicate that faecal matter and animal manure biochars have shown great potential to promote Cd immobilization and lettuce growth response in heavily contaminated agricultural fields.Electronic supplementary materialThe online version of this article (doi:10.1186/s40064-016-2019-6) contains supplementary material, which is available to authorized users.

Effect of cow manure biochar on maize productivity under sandy soil condition

AbstractIn this study, we performed a greenhouse experiment to investigate the effect of cow manure biochar on maize yield, nutrient uptake and physico‐chemical properties of a dryland sandy soil. Biochar was derived from dry cow manure pyrolysed at 500 °C. Cow manure biochar was mixed with a sandy soil at the rate equivalent to 0, 10, 15 and 20 t biochar per hectare. Maize was used as a test crop. Results of the study indicated that cow manure biochar contains some important plant nutrients which significantly affected the maize crop growth. Maize yield and nutrient uptake were significantly improved with increasing the biochar mixing rate. Application of biochar at 15 and 20 t/ha mixing rates significantly increased maize grain yield by 150 and 98% as compared with the control, respectively. Maize net water use efficiency (WUE) increased by 6, 139 and 91% as compared with the control, with the 10, 15 and 20 t/ha mixing rate, respectively. Nutrient uptake by maize grain was significantly increased with higher biochar applications. Application of cow manure biochar improved the field‐saturated hydraulic conductivity of the sandy soil, as a result net WUE also increased. Results of the soil analysis after the harvesting indicated significant increase in the pH, total C, total N, Oslen‐P, exchangeable cations and cation exchange capacity. The results of this study indicated that application of cow manure biochar to sandy soil is not only beneficial for crop growth but it also significantly improved the physico‐chemical properties of the coarse soil.