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1.
    
Global interest in studying biochar stems from its ability to sequester carbon in soil and render nutrients and moisture more readily available to root systems. Therefore, a bibliometric analysis was conducted to investigate global scientific publications related to biochar research, providing insight into the number of articles published, journal platforms, subjects, citations, and overall trends. The primary databases employed were the Web of Science and Science Citation Index. A total of 1,697 articles published between 2000 and 2015 were evaluated. This systematic bibliometric analysis will assist research groups and individuals to understand global biochar research trends and focus future research. The influence of biochar on soil, plants, and the environment continues to require greater attention.  相似文献   
2.
    
Suitable predictors of degradability are sought to support the identification of biochars with large potential to increase C sequestration in soils. We determined the biodegradation of 9 chars from hydrothermal carbonization and pyrolysis in two agricultural soils. The 200‐ and 115‐day degradation correlated strongly with the O:C‐ and slightly with the H:C‐atomic ratio of 9 and 14 biochars, respectively. Highest temperature treatment and ash content did not show similar correlations.  相似文献   
3.
ABSTRACT

The formation of phosphorus (P) compounds including iron-P, aluminum-P and calcium-P in highly weathered tropical soils can be altered upon biochar addition. We investigated the effect of corn cob biochar (CC) and rice husk biochar (RH) pyrolyzed at three temperatures (300°C, 450°C and 650°C) on phosphorus (P) fractions of three contrasting soils. A 90d incubation study was conducted by mixing biochar with soil at a rate of 1% w/w and at 70% field capacity. Sequential P fraction was performed on biochar, soil and soil-biochar mixtures. Increase in most labile P (resin-Pi, NaHCO3-Pi) and organic P fraction (NaHCO3-Po + NaOH-Po) in CC and RH biochars were inversely related to increasing temperature. HCl-Pi and residual P increased with increasing temperature. Interaction of CC and RH with soils resulted in an increase in most labile P as well as moderately labile P (NaOH-Pi) fractions in the soils. CC increased most labile P in the soils more than RH. The increase in most labile P fraction in soils was more significant at relatively lower temperatures (300°C and 450°C) than 650°C. However, the increase in HCl-Pi and residual P of the soils was more predominant at high temperature (650°C). The study suggested that biochar pyrolyzed at 300–450°C could be used to increase P bioavailability in tropical soils.  相似文献   
4.
With the depletion of global phosphorous (P) reserves, finding alternatives to P fertilizers has been gaining more and more attention. This study was conducted to identify whether biochar application could improve P availability in a P-deficient alkaline alluvial soil. Unground biochar contained a high level of 692 mg kg?1 extractable P, over 100 times more than that in the soil. Extractable P content increased significantly with the decrease of biochar particle size. There was a significant positive correlation between soil available P content and biochar application rates. The pot experiment showed that biochar application significantly increased the soil available P content before sowing, and significantly improved the aboveground biomass of soybean and promoted P uptake at harvest. Biochar, as containing abundant extractable P, could go partly on substituting mineral P fertilizers as well as promote plant growth and reduce P fertilizer application in agriculture.  相似文献   
5.
The conversion of vegetative biomass waste to biochar (biologically derived charcoal) is a source of carbon (C) that can be used to increase the level of soil organic C (SOC) in agricultural soils. This review collates available research into the effects of biologically derived C species with respect to the direct and indirect effects on agricultural productivity and their potential for use in Western Australian agricultural systems. There is a growing requirement to quantify the effect of specific biochar applications for agroecological purposes and to verify biosequestered C for climate-change-mitigation activities. This work provides a review and assessment of safe biochar application rates and examines the present levels of scientific uncertainty surrounding the efficacy and reliability of applying biochar to soils in relation to crop productivity.  相似文献   
6.
    
Biochar has recently received increased attention because it improves poor soil fertility. However, its potentiality to enhance soil physical properties under water stress conditions not yet deeply investigated. Hence, extensive field investigations were carried out to study the effects of biochar addition (BA) with deficit irrigation (DI) on soil bulk density (BD), porosity percentage (P%), soil moisture content (SMC%), soil hydraulic conductivity (K), cucumber yield and water use efficiency (WUE) during two consecutive seasons (2016 and 2017). The biochar treatments were B0 (0 ton ha?1), B1 (10 ton ha?1and B2 (20 ton ha?1), while the DI treatments were 1.0 (W1), 0.60 (W2) and 0.40 (W3) of the reference evapotranspiration (ET0). The parameters were measured at soil depths of 0–10 (d1), 10–20 (d2) and 20–30 cm (d3) for measurement periods of before sowing (P1), mid-season (P2) and after harvest (P3). The results showed that the B2W1 combination gave the highest yield (57 and 45.2 t ha?1), WUE (10.94 and 11.27 kg m?3), SMC (39.2 and 40.1%) in both seasons, respectively. The B2W3 had the highest porosity (47.5 and 46.1%) values at the d1. Meanwhile, the lowest soil BD values of 1.1 and 1.05 g cm?3 were obtained by the B2W1 at d1 for 2.16 and 2017, respectively. Statistically, most of the parameters studied under B2W2 and B0W1 had non-significant differences between them. Hence, the addition of biochar with DI could be an integrated approach to address the drought stress, while enhancing soil and plant properties.  相似文献   
7.
Salinity is a major abiotic stress that affects crop production throughout the world. Biochar is an activated carbon soil conditioner that can alleviate the negative impacts of salinity. The research was conducted to evaluate the ameliorative effect of 1% and 2% of biochar application on wheat seed germination and growth attributes under salinity. Both levels of biochar improved the germination and growth conditions under salinity; however, 2% biochar level was more effective compared to 1% level. Root and shoot length increased up to 23% and11% with 2% biochar, respectively. The maximum increase of 16% and 10% in leaf water potential and osmotic potential was noted with 2% biochar at 150 mM salt. The decrease in proline content and soluble sugar at 2% biochar was 51% and 27%, respectively. Decrease in superoxide dismutase activity was 15.3% at 2% level of biochar under stress biochar mitigates the negative effects of salinity and improved wheat productivity.  相似文献   
8.
This work studies the adsorption and degradation of 2,4-dichlorophenoxyacetic (2,4-D) in spiked soil with nanoscale Fe0 particles (nFe0) and biochar derived from maize straw. When biochar concentration was high, the adsorption capacity of soil was enhanced. Furthermore, 2,4-D degraded completely at loading rates of 0.33 and 0.17 g/L nFe0 plus biochar (initial 2,4-D concentration of 10 mg/g) within 40 h, according to equilibrium data. Additionally, the theoretical concentration of chloridion was approximately 84%. Further analysis indicated that the effect of nFe0 on 2,4-D degradation was weaker in soil columns than that in soil slurry. By contrast, 2,4-D degradation is positively influenced by biochar application, which prevented the aggregation and corrosion of Fe nanoparticles. Although the enhanced capacity for 2,4-D adsorption on the soil decelerated dechlorination rate, long-term nFe0 activity was generated. After 72 h, the efficiency of 2,4-D degradation was approximately 53.2% in the soil columns with biochar support.  相似文献   
9.
    
A pot experiment was conducted in a climate‐controlled greenhouse to investigate the growth, physiology and yield of potato in response to salinity stress under biochar amendment. It was hypothesized that addition of biochar may improve plant growth and yield by mitigating the negative effect of salinity through its high sorption ability. From tuber bulking to harvesting, the plants were exposed to three saline irrigations, that is 0, 25 and 50 mm NaCl solutions, respectively, and two levels of biochar (0 % and 5 % W/W) treatments. An adsorption study was also conducted to study the Na+ adsorption capability of biochar. Results indicated that biochar was capable to ameliorate salinity stress by adsorbing Na+. Increasing salinity level resulted in significant reductions of shoot biomass, root length and volume, tuber yield, photosynthetic rate (An), stomatal conductance (gs), midday leaf water potential, but increased abscisic acid (ABA) concentration in both leaf and xylem sap. At each salinity level, incorporation of biochar increased shoot biomass, root length and volume, tuber yield, An, gs, midday leaf water potential, and decreased ABA concentration in the leaf and xylem sap as compared with the respective non‐biochar control. Decreased Na+, Na+/K+ ratio and increased K+ content in xylem with biochar amendment also indicated its ameliorative effects on potato plants in response to salinity stress. The results suggested that incorporation of biochar might be a promising approach for enhancing crop productivity in salt‐affected soils.  相似文献   
10.
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