Exploring the suitability of biochar for improving soil quality under different water and salt conditions is important for maintaining soil health and productivity in the arid regions of northwestern China.We compared...Exploring the suitability of biochar for improving soil quality under different water and salt conditions is important for maintaining soil health and productivity in the arid regions of northwestern China.We compared the effects of biochar application practices on soil physical,chemical and biological properties under different irrigation and water salinity levels in a two-year field experiment in a mulched and drip-irrigated maize field in Gansu Province,China.Eight treatments in total included the combination of two biochar addition rates of 0 t ha–1(B0)and 60 t ha–1(B1),two irrigation levels of full(W1)and deficit irrigation(W2;W2=1/2 W1)and two water salinity levels of fresh water(S0,0.71 g L–1)and brackish water(S1,4.00 g L–1).The minimum dataset method was used to calculate the soil quality index(SQI)under different treatments.Deficit and brackish water irrigation significantly reduced SQI by 3.80–9.80%through reducing some soil physical,chemical and biological properties.Biochar application significantly increased the SQI by 6.13 and 10.40%under full irrigation with fresh and brackish water,respectively.Biochar addition enhanced the relative abundance of beneficial bacteria(e.g.,Proteobacteria,Patescibacteria)in the soil in all water–salt treatments.The partial least squares path model showed that biochar application significantly enhanced the SQI mainly by improving soil aggregation and pore structure under particular water–salt conditions.This research provides an important basis for utilizing biochar to improve soil quality in arid regions of Northwest China under various water–salt conditions.展开更多
Boreal forests commonly suff er from nitrogen defi ciency due to low rate of nitrogen mineralization.Biochar may promote soil organic matter decomposition and accelerate nitrogen mineralization.In this study,Illumina ...Boreal forests commonly suff er from nitrogen defi ciency due to low rate of nitrogen mineralization.Biochar may promote soil organic matter decomposition and accelerate nitrogen mineralization.In this study,Illumina NovaSeq sequencing combined with functional annotation of prokaryotic taxa(FAPROTAX)analysis was used to investigate the eff ect of biochar pyrolysis temperatures,the amount of applied biochar,and the period since the biochar application(2-and 3-year)on soil bacterial communities.The results show that biochar pyrolysis temperatures(500℃ and 650℃)and the amount of applied biochar(0.5 kg m^(−2)and 1.0 kg m^(−2))did not change soil properties.Nevertheless,the interaction of biochar pyrolysis temperature and the amount had signifi cant eff ects on bacterial species richness and evenness(P<0.05).The application of biochar produced at 500℃ had a lower abundance of Actinobacteria and Verrucomicrobia,while that produced at 650℃ had a higher abundance of Conexibacter and Phenylobacterium.When biochar produced at 650℃ was applied,applying 0.5 kg m^(−2)had a higher abundance of Cyanobacteria,Conexibacter,and Phenylobacterium than that of 1.0 kg m^(−2)(P<0.05).Functionally,the abundance of the aromatic compound degradation group increased with the extension of application time and increase of pyrolysis temperature.The time since application played an important role in the formation of soil bacterial communities and their functional structure.Long-term studies are necessary to understand the consequence of biochar on bacterial communities in boreal forests.展开更多
The impact of biochar application on plant performance under drought stress necessitates a comprehensive understanding of biochar-soil interaction,root growth,and plant physiological processes.Therefore,pot experiment...The impact of biochar application on plant performance under drought stress necessitates a comprehensive understanding of biochar-soil interaction,root growth,and plant physiological processes.Therefore,pot experiments were conducted to assess the effects of biochar on plant responses to drought stress at the seedling stage.Two contrasting maize genotypes(drought-sensitive KN5585 vs.-tolerant Mo17)were subjected to biochar application under drought stress conditions.The results indicated that biochar application decreased soil exchangeable Na+and Ca^(2+)contents while increased soil exchangeable K^(+)content(2.7-fold)and electrical conductivity(4.0-fold),resulting in an elevated leaf sap K^(+)concentration in both maize genotypes.The elevated K^(+)concentration with biochar application increased root apoplastic pH in the drought-sensitive KN5585,but not in the drought-tolerant Mo17,which stimulated the activation of H^(+)-ATPase and H^(+)efflux in KN5585 roots.Apoplast alkalinization of the drought-sensitive KN5585 resulting from biochar application further inhibited root growth by 30.7%,contributing to an improvement in water potential,a reduction in levels of O_(2)^(-),H_(2)O_(2),T-AOC,SOD,and POD,as well as the down-regulation of genes associated with drought resistance in KN5585 roots.In contrast,biochar application increased leaf sap osmolality and provided osmotic protection for the drought-tolerant Mo17,which was associated with trehalose accumulation in Mo17 roots.Biochar application improved sucrose utilization and circadian rhythm of Mo17 roots,and increased fresh weight under drought stress.This study suggests that biochar application has the potential to enhance plant drought tolerance,which is achieved through the inhibition of root growth in sensitive plants and the enhancement of osmotic protection in tolerant plants,respectively.展开更多
Biochar has been extensively utilized to amend soil and mitigate greenhouse gas(GHG)emissions from croplands.However,the effectiveness of biochar application in reducing cropland GHG emissions remains uncertain due to...Biochar has been extensively utilized to amend soil and mitigate greenhouse gas(GHG)emissions from croplands.However,the effectiveness of biochar application in reducing cropland GHG emissions remains uncertain due to variations in soil properties and environmental conditions across regions.In this study,the impact of biochar surface functional groups on soil GHG emissions was investigated using molecular model calculation.Machine learning(ML)technology was applied to predict the responses of soil GHG emissions and crop yields under different biochar feedstocks and application rates,aiming to determine the optimum biochar application strategies based on specific soil properties and environmental conditions on a global scale.The findings suggest that the functional groups play an essential role in determining biochar surface activity and the soil’s capacity for adsorbing GHGs.ML was an effective method in predicting the changes in soil GHG emissions and crop yield following biochar application.Moreover,poor-fertility soils exhibited greater changes in GHG emissions compared to fertile soil.Implementing an optimized global strategy for biochar application may result in a substantial reduction of 684.25 Tg year^(−1)CO_(2)equivalent(equivalent to 7.87%of global cropland GHG emissions)while simultaneously improving crop yields.This study improves our understanding of the interaction between biochar surface properties and soil GHG,confirming the potential of global biochar application strategies in mitigating cropland GHG emissions and addressing global climate degradation.Further research efforts are required to optimize such strategies.展开更多
Tomato(Solanum lycopersicum L.)production was threatened by the inefficiency of fertilizers,contributing to the deterioration of the soil environment under greenhouse conditions in southern China.Biochar application c...Tomato(Solanum lycopersicum L.)production was threatened by the inefficiency of fertilizers,contributing to the deterioration of the soil environment under greenhouse conditions in southern China.Biochar application could ameliorate the physical properties of soil and enhance the growth and productivity of tomatoes.In this study,a pot experiment was conducted with four biochar addition rates of 0%(BA0),1%(BA1),3%(BA3),and 5%(BA5).Results showed that the soil physical properties,morph-physiological indicators,yield,and water use efficiency(WUE)of tomatoes with biochar addition were significantly higher than those of tomatoes without biochar addition.Among the different treatments,BA5 provided the highest total porosity(53.09%),field capacity(40.73%),plant height(72.5 cm),net photosynthetic rate(16.04 mmol/m^(2)·s),total dry matter(184.65 g/plant),yield(54.9 t/hm^(2)),and WUE(38.5 kg/m^(3)).The yield and WUE increased from 44.5 t/hm^(2) and 31.2 kg/m^(3) under BA0,respectively,to 54.9 t/hm^(2) and 38.5 kg/m^(3) under BA5,respectively.The results suggest that BA5 can maximize improvements in soil physical properties to augment plant growth,thereby increasing the yield and WUE of tomatoes.However,the effects of BA3 and BA5 on WUE were not significantly different.Thus,from the perspective of economic investment,BA3 is recommended.展开更多
Background: Nitrogen(N) deposition affects soil greenhouse gas(GHG) emissions, while biochar application reduces GHG emissions in agricultural soils. However, it remains unclear whether biochar amendment can alleviate...Background: Nitrogen(N) deposition affects soil greenhouse gas(GHG) emissions, while biochar application reduces GHG emissions in agricultural soils. However, it remains unclear whether biochar amendment can alleviate the promoting effects of N input on GHG emissions in forest soils. Here, we quantify the separate and combined effects of biochar amendment(0, 20, and 40 t·ha) and N addition(0, 30, 60, and 90 kg N·ha·yr) on soil GHG fluxes in a long-term field experiment at a Moso bamboo(Phyllostachys edulis) plantation.Results: Low and moderate N inputs(≤60 kg N·ha·yr) significantly increase mean annual soil carbon dioxide(CO) and nitrous oxide(NO) emissions by 17.0%–25.4% and 29.8%–31.2%, respectively, while decreasing methane(CH) uptake by 12.4%–15.9%, leading to increases in the global warming potential(GWP) of soil CHand NO fluxes by 32.4%–44.0%. Moreover, N addition reduces soil organic carbon(C;SOC) storage by 0.2%–6.5%. Compared to the control treatment, biochar amendment increases mean annual soil CO2emissions, CHuptake, and SOC storage by 18.4%–25.4%, 7.6%–15.8%, and 7.1%–13.4%, respectively, while decreasing NO emissions by 17.6%–19.2%, leading to a GWP decrease of 18.4%–21.4%. Biochar amendments significantly enhance the promoting effects of N addition on soil COemissions, while substantially offsetting the promotion of N2O emissions, inhibition of CHuptake, and decreased SOC storage, resulting in a GWP decrease of 9.1%–30.3%.Additionally, soil COand CHfluxes are significantly and positively correlated with soil microbial biomass C(MBC) and pH. Meanwhile, NO emissions have a significant and positive correlation with soil MBC and a negative correlation with pH.Conclusions: Biochar amendment can increase SOC storage and offset the enhanced GWP mediated by elevated N deposition and is, thus, a potential strategy for increasing soil C sinks and decreasing GWPs of soil CHand NO under increasing atmospheric N deposition in Moso bamboo plantations.展开更多
Biochar application is claimed to improve nutrient availability in many problem soils;however, pristine biochars are often reported to produce inconsistent results. Therefore, appropriate biochar modification techniqu...Biochar application is claimed to improve nutrient availability in many problem soils;however, pristine biochars are often reported to produce inconsistent results. Therefore, appropriate biochar modification techniques are required to retain soil nutrients at an optimum level. To increase Nitrogen (N) and Phosphorus (P) availability in coastal saline soil, two slow pyrolyzed biochars viz domestic organic waste (DWB) and farmyard manure (FMB) were modified with MgCl<sub>2</sub>. Ten different treatments comprising the biochars (pristine and modified) with and without the recommended fertilizer were applied (2% w/w) to the soil and incubated for ninety days. The soils were analyzed for pH, EC, available <img src="Edit_0d6ce0cb-4936-4874-a480-35d5b2f585ff.png" alt="" />, <img src="Edit_64cd5bd3-ddeb-4e08-ad2e-48f0710feace.png" alt="" /> and different phosphorus fractions sequentially extracted by NH<sub>4</sub>Cl, NaHCO<sub>3</sub>, NaOH, and HCl. During the incubation period, biochar treatments increased all phosphorus and nitrogen fractions than the control and recommended fertilizer treatment. The application of FMB significantly (<em>p</em> < 0.05) increased NH<sub>4</sub>Cl, NaHCO<sub>3</sub>, and NaOH extractable P fractions from DWB, while HCl soluble fraction was enhanced (<em>p</em> > 0.05) by DWB. The increased Al and/or Fe bound phosphate after 60 days of incubation had significant correlations to decreasing soil pH and NaHCO<sub>3</sub>-P, indicating reduced availability with time. Further Mg modification slightly increased P availability only after 60 days of incubation. The modification also improved both nitrogen fractions but significantly (<em>p</em> < 0.05) increased the NO<sub>3</sub>-N content which could be the result of electrostatic attraction between Mg<sup>2</sup>+ and <img src="Edit_c55861ac-dd25-4c26-9ecc-2e134a948b8e.png" alt="" /> ions. Overall, Mg-modified biochar may retain both phosphates and nitrates in soil. However, the magnitude of retention will vary depending on biochar type, nutrient species, and aging in soil.展开更多
In a beamhouse,liming plays a key role in the removal of hair/wool and epidermis,but problems are created when waste liming sludge is discharged to the environment.The treatment of tannery wastewater is another major ...In a beamhouse,liming plays a key role in the removal of hair/wool and epidermis,but problems are created when waste liming sludge is discharged to the environment.The treatment of tannery wastewater is another major challenge to the industry.In this study,thermally-activated biochars derived from liming sludge were studied for their effective adsorption of chromium(Cr)from the tannery wastewater.The thermally activated biochars(B500,B550,B600,and B650)were prepared at different temperatures from the liming sludge.Their characteristics before and after the treatment were investigated using Fourier transform infrared spectroscopy,energy dispersive X-ray spectroscopy,Bru-nauer-Emmett-Teller,and scanning electron microscopy analyses.The related functional groups(C-H,O-H,C-N,and=C-O)and chromium adsorption capacity were determined according to the surface morphology,element contents(C,O,Ca,Na,Al,Mg,and Si),surface area(5.8-9.2 m^(2)/g),pore size(5.22-5.53 nm),and particle size(652-1034 nm)of the experimental biochars.The biochar originated at 600°C from the tannery liming sludge(B600)had a greater surface area with a chromium adsorption capacity of 99.8%in comparison to B500,B550,and B650 biochars.This study developed an innovative way of utilizing liming sludge waste to minimize the pollution load and wastewater treatment cost in the tannery industry.展开更多
Combined straw and straw-derived biochar input is commonly applied by farmland management in low-fertility soils.Although straw return increases soil organic matter(SOM)contents,it also primes SOM mineralization.The m...Combined straw and straw-derived biochar input is commonly applied by farmland management in low-fertility soils.Although straw return increases soil organic matter(SOM)contents,it also primes SOM mineralization.The mechanisms by which active microorganisms mineralize SOM and the underlying factors remain unclear for such soils.To address these issues,paddy soil was amended with^(13)C-labeled straw,with and without biochar(BC)or ferrihydrite(Fh),and incubated for 70 days under flooded conditions.Compound-specific^(13)C analysis of phospholipid fatty acids(^(13)C-PLFAs)allowed us to identify active microbial communities utilizing the^(13)C-labeled straw and specific groups involved in SOM mineralization.Cumulative SOM mineralization increased by 61%and 27%in soils amended with Straw+BC and Straw+Fh+BC,respectively,compared to that with straw only.The total PLFA content was independent of the straw and biochar input.However,^(13)C-PLFAs contents increased by 35-82%after biochar addition,reflecting accelerated microbial turnover.Compared to that in soils without biochar addition,those with biochar had an altered microbial community composition-increased amounts of^(13)C-labeled gram-positive bacteria(^(13)C-Gram+)and fungi,which were the main active microorganisms mineralizing SOM.Microbial reproduction and growth were susceptible to nutrient availability.^(13)C-Gram+and^(13)C-fungi increased with Olsen P but decreased with dissolved organic carbon and NO−3 contents.In conclusion,biochar acts as an electron shuttle,stimulates iron reduction,and releases organic carbon from soil minerals,which in turn increases SOM mineralization.Gram+and fungi were involved in straw decomposition in response to biochar application and responsible for SOM mineralization.展开更多
基金supported by the National Key R&D Program of China(2022YFD1900401)。
文摘Exploring the suitability of biochar for improving soil quality under different water and salt conditions is important for maintaining soil health and productivity in the arid regions of northwestern China.We compared the effects of biochar application practices on soil physical,chemical and biological properties under different irrigation and water salinity levels in a two-year field experiment in a mulched and drip-irrigated maize field in Gansu Province,China.Eight treatments in total included the combination of two biochar addition rates of 0 t ha–1(B0)and 60 t ha–1(B1),two irrigation levels of full(W1)and deficit irrigation(W2;W2=1/2 W1)and two water salinity levels of fresh water(S0,0.71 g L–1)and brackish water(S1,4.00 g L–1).The minimum dataset method was used to calculate the soil quality index(SQI)under different treatments.Deficit and brackish water irrigation significantly reduced SQI by 3.80–9.80%through reducing some soil physical,chemical and biological properties.Biochar application significantly increased the SQI by 6.13 and 10.40%under full irrigation with fresh and brackish water,respectively.Biochar addition enhanced the relative abundance of beneficial bacteria(e.g.,Proteobacteria,Patescibacteria)in the soil in all water–salt treatments.The partial least squares path model showed that biochar application significantly enhanced the SQI mainly by improving soil aggregation and pore structure under particular water–salt conditions.This research provides an important basis for utilizing biochar to improve soil quality in arid regions of Northwest China under various water–salt conditions.
基金funded by The Foundation for Research of Natural Resources in Finland(2016085)supported by the Academy of Finland(286685,294600,307222,277623)the FCoE of atmospheric sciences(Center of Excellence(1118615)).
文摘Boreal forests commonly suff er from nitrogen defi ciency due to low rate of nitrogen mineralization.Biochar may promote soil organic matter decomposition and accelerate nitrogen mineralization.In this study,Illumina NovaSeq sequencing combined with functional annotation of prokaryotic taxa(FAPROTAX)analysis was used to investigate the eff ect of biochar pyrolysis temperatures,the amount of applied biochar,and the period since the biochar application(2-and 3-year)on soil bacterial communities.The results show that biochar pyrolysis temperatures(500℃ and 650℃)and the amount of applied biochar(0.5 kg m^(−2)and 1.0 kg m^(−2))did not change soil properties.Nevertheless,the interaction of biochar pyrolysis temperature and the amount had signifi cant eff ects on bacterial species richness and evenness(P<0.05).The application of biochar produced at 500℃ had a lower abundance of Actinobacteria and Verrucomicrobia,while that produced at 650℃ had a higher abundance of Conexibacter and Phenylobacterium.When biochar produced at 650℃ was applied,applying 0.5 kg m^(−2)had a higher abundance of Cyanobacteria,Conexibacter,and Phenylobacterium than that of 1.0 kg m^(−2)(P<0.05).Functionally,the abundance of the aromatic compound degradation group increased with the extension of application time and increase of pyrolysis temperature.The time since application played an important role in the formation of soil bacterial communities and their functional structure.Long-term studies are necessary to understand the consequence of biochar on bacterial communities in boreal forests.
基金funded by the National Key Research and Development Program of China(Grant no.2023YFD1500900).
文摘The impact of biochar application on plant performance under drought stress necessitates a comprehensive understanding of biochar-soil interaction,root growth,and plant physiological processes.Therefore,pot experiments were conducted to assess the effects of biochar on plant responses to drought stress at the seedling stage.Two contrasting maize genotypes(drought-sensitive KN5585 vs.-tolerant Mo17)were subjected to biochar application under drought stress conditions.The results indicated that biochar application decreased soil exchangeable Na+and Ca^(2+)contents while increased soil exchangeable K^(+)content(2.7-fold)and electrical conductivity(4.0-fold),resulting in an elevated leaf sap K^(+)concentration in both maize genotypes.The elevated K^(+)concentration with biochar application increased root apoplastic pH in the drought-sensitive KN5585,but not in the drought-tolerant Mo17,which stimulated the activation of H^(+)-ATPase and H^(+)efflux in KN5585 roots.Apoplast alkalinization of the drought-sensitive KN5585 resulting from biochar application further inhibited root growth by 30.7%,contributing to an improvement in water potential,a reduction in levels of O_(2)^(-),H_(2)O_(2),T-AOC,SOD,and POD,as well as the down-regulation of genes associated with drought resistance in KN5585 roots.In contrast,biochar application increased leaf sap osmolality and provided osmotic protection for the drought-tolerant Mo17,which was associated with trehalose accumulation in Mo17 roots.Biochar application improved sucrose utilization and circadian rhythm of Mo17 roots,and increased fresh weight under drought stress.This study suggests that biochar application has the potential to enhance plant drought tolerance,which is achieved through the inhibition of root growth in sensitive plants and the enhancement of osmotic protection in tolerant plants,respectively.
基金the National Natural Science Foundation of China(Grant Number:U20A20107)the Western Light Young Scholars Project,Chinese Academy of Sciences(2022).
文摘Biochar has been extensively utilized to amend soil and mitigate greenhouse gas(GHG)emissions from croplands.However,the effectiveness of biochar application in reducing cropland GHG emissions remains uncertain due to variations in soil properties and environmental conditions across regions.In this study,the impact of biochar surface functional groups on soil GHG emissions was investigated using molecular model calculation.Machine learning(ML)technology was applied to predict the responses of soil GHG emissions and crop yields under different biochar feedstocks and application rates,aiming to determine the optimum biochar application strategies based on specific soil properties and environmental conditions on a global scale.The findings suggest that the functional groups play an essential role in determining biochar surface activity and the soil’s capacity for adsorbing GHGs.ML was an effective method in predicting the changes in soil GHG emissions and crop yield following biochar application.Moreover,poor-fertility soils exhibited greater changes in GHG emissions compared to fertile soil.Implementing an optimized global strategy for biochar application may result in a substantial reduction of 684.25 Tg year^(−1)CO_(2)equivalent(equivalent to 7.87%of global cropland GHG emissions)while simultaneously improving crop yields.This study improves our understanding of the interaction between biochar surface properties and soil GHG,confirming the potential of global biochar application strategies in mitigating cropland GHG emissions and addressing global climate degradation.Further research efforts are required to optimize such strategies.
基金The authors acknowledge that this work was financially supported by the National Key Research and Development Program of China(Grant No.2019YFD1001900).
文摘Tomato(Solanum lycopersicum L.)production was threatened by the inefficiency of fertilizers,contributing to the deterioration of the soil environment under greenhouse conditions in southern China.Biochar application could ameliorate the physical properties of soil and enhance the growth and productivity of tomatoes.In this study,a pot experiment was conducted with four biochar addition rates of 0%(BA0),1%(BA1),3%(BA3),and 5%(BA5).Results showed that the soil physical properties,morph-physiological indicators,yield,and water use efficiency(WUE)of tomatoes with biochar addition were significantly higher than those of tomatoes without biochar addition.Among the different treatments,BA5 provided the highest total porosity(53.09%),field capacity(40.73%),plant height(72.5 cm),net photosynthetic rate(16.04 mmol/m^(2)·s),total dry matter(184.65 g/plant),yield(54.9 t/hm^(2)),and WUE(38.5 kg/m^(3)).The yield and WUE increased from 44.5 t/hm^(2) and 31.2 kg/m^(3) under BA0,respectively,to 54.9 t/hm^(2) and 38.5 kg/m^(3) under BA5,respectively.The results suggest that BA5 can maximize improvements in soil physical properties to augment plant growth,thereby increasing the yield and WUE of tomatoes.However,the effects of BA3 and BA5 on WUE were not significantly different.Thus,from the perspective of economic investment,BA3 is recommended.
基金sponsored by the National Natural Science Foundation of China,China(Grant Nos.31470529,32125027)Zhejiang A&F University Research and Development Fund,China(Nos.2022LFR006,2021LFR060).
文摘Background: Nitrogen(N) deposition affects soil greenhouse gas(GHG) emissions, while biochar application reduces GHG emissions in agricultural soils. However, it remains unclear whether biochar amendment can alleviate the promoting effects of N input on GHG emissions in forest soils. Here, we quantify the separate and combined effects of biochar amendment(0, 20, and 40 t·ha) and N addition(0, 30, 60, and 90 kg N·ha·yr) on soil GHG fluxes in a long-term field experiment at a Moso bamboo(Phyllostachys edulis) plantation.Results: Low and moderate N inputs(≤60 kg N·ha·yr) significantly increase mean annual soil carbon dioxide(CO) and nitrous oxide(NO) emissions by 17.0%–25.4% and 29.8%–31.2%, respectively, while decreasing methane(CH) uptake by 12.4%–15.9%, leading to increases in the global warming potential(GWP) of soil CHand NO fluxes by 32.4%–44.0%. Moreover, N addition reduces soil organic carbon(C;SOC) storage by 0.2%–6.5%. Compared to the control treatment, biochar amendment increases mean annual soil CO2emissions, CHuptake, and SOC storage by 18.4%–25.4%, 7.6%–15.8%, and 7.1%–13.4%, respectively, while decreasing NO emissions by 17.6%–19.2%, leading to a GWP decrease of 18.4%–21.4%. Biochar amendments significantly enhance the promoting effects of N addition on soil COemissions, while substantially offsetting the promotion of N2O emissions, inhibition of CHuptake, and decreased SOC storage, resulting in a GWP decrease of 9.1%–30.3%.Additionally, soil COand CHfluxes are significantly and positively correlated with soil microbial biomass C(MBC) and pH. Meanwhile, NO emissions have a significant and positive correlation with soil MBC and a negative correlation with pH.Conclusions: Biochar amendment can increase SOC storage and offset the enhanced GWP mediated by elevated N deposition and is, thus, a potential strategy for increasing soil C sinks and decreasing GWPs of soil CHand NO under increasing atmospheric N deposition in Moso bamboo plantations.
文摘Biochar application is claimed to improve nutrient availability in many problem soils;however, pristine biochars are often reported to produce inconsistent results. Therefore, appropriate biochar modification techniques are required to retain soil nutrients at an optimum level. To increase Nitrogen (N) and Phosphorus (P) availability in coastal saline soil, two slow pyrolyzed biochars viz domestic organic waste (DWB) and farmyard manure (FMB) were modified with MgCl<sub>2</sub>. Ten different treatments comprising the biochars (pristine and modified) with and without the recommended fertilizer were applied (2% w/w) to the soil and incubated for ninety days. The soils were analyzed for pH, EC, available <img src="Edit_0d6ce0cb-4936-4874-a480-35d5b2f585ff.png" alt="" />, <img src="Edit_64cd5bd3-ddeb-4e08-ad2e-48f0710feace.png" alt="" /> and different phosphorus fractions sequentially extracted by NH<sub>4</sub>Cl, NaHCO<sub>3</sub>, NaOH, and HCl. During the incubation period, biochar treatments increased all phosphorus and nitrogen fractions than the control and recommended fertilizer treatment. The application of FMB significantly (<em>p</em> < 0.05) increased NH<sub>4</sub>Cl, NaHCO<sub>3</sub>, and NaOH extractable P fractions from DWB, while HCl soluble fraction was enhanced (<em>p</em> > 0.05) by DWB. The increased Al and/or Fe bound phosphate after 60 days of incubation had significant correlations to decreasing soil pH and NaHCO<sub>3</sub>-P, indicating reduced availability with time. Further Mg modification slightly increased P availability only after 60 days of incubation. The modification also improved both nitrogen fractions but significantly (<em>p</em> < 0.05) increased the NO<sub>3</sub>-N content which could be the result of electrostatic attraction between Mg<sup>2</sup>+ and <img src="Edit_c55861ac-dd25-4c26-9ecc-2e134a948b8e.png" alt="" /> ions. Overall, Mg-modified biochar may retain both phosphates and nitrates in soil. However, the magnitude of retention will vary depending on biochar type, nutrient species, and aging in soil.
文摘In a beamhouse,liming plays a key role in the removal of hair/wool and epidermis,but problems are created when waste liming sludge is discharged to the environment.The treatment of tannery wastewater is another major challenge to the industry.In this study,thermally-activated biochars derived from liming sludge were studied for their effective adsorption of chromium(Cr)from the tannery wastewater.The thermally activated biochars(B500,B550,B600,and B650)were prepared at different temperatures from the liming sludge.Their characteristics before and after the treatment were investigated using Fourier transform infrared spectroscopy,energy dispersive X-ray spectroscopy,Bru-nauer-Emmett-Teller,and scanning electron microscopy analyses.The related functional groups(C-H,O-H,C-N,and=C-O)and chromium adsorption capacity were determined according to the surface morphology,element contents(C,O,Ca,Na,Al,Mg,and Si),surface area(5.8-9.2 m^(2)/g),pore size(5.22-5.53 nm),and particle size(652-1034 nm)of the experimental biochars.The biochar originated at 600°C from the tannery liming sludge(B600)had a greater surface area with a chromium adsorption capacity of 99.8%in comparison to B500,B550,and B650 biochars.This study developed an innovative way of utilizing liming sludge waste to minimize the pollution load and wastewater treatment cost in the tannery industry.
基金supported by the National Science Foundation of China(42177334,42207343,42267050)the Ningbo Science and Technology Bureau(2022Z168)+1 种基金the“Pioneer”and“Leading Goose”R&D Program of Zhejiang(2023C02016,2022C02008)the Seagull Talent of Yongjiang Talent for Yakov Kuzyakov and the K.C.Wong Magna Fund at Ningbo University,Strategic Academic Leadership Program"Priority 2030"of the Kazan Federal University,and the RUDN University Strategic Academic Leadership Program.
文摘Combined straw and straw-derived biochar input is commonly applied by farmland management in low-fertility soils.Although straw return increases soil organic matter(SOM)contents,it also primes SOM mineralization.The mechanisms by which active microorganisms mineralize SOM and the underlying factors remain unclear for such soils.To address these issues,paddy soil was amended with^(13)C-labeled straw,with and without biochar(BC)or ferrihydrite(Fh),and incubated for 70 days under flooded conditions.Compound-specific^(13)C analysis of phospholipid fatty acids(^(13)C-PLFAs)allowed us to identify active microbial communities utilizing the^(13)C-labeled straw and specific groups involved in SOM mineralization.Cumulative SOM mineralization increased by 61%and 27%in soils amended with Straw+BC and Straw+Fh+BC,respectively,compared to that with straw only.The total PLFA content was independent of the straw and biochar input.However,^(13)C-PLFAs contents increased by 35-82%after biochar addition,reflecting accelerated microbial turnover.Compared to that in soils without biochar addition,those with biochar had an altered microbial community composition-increased amounts of^(13)C-labeled gram-positive bacteria(^(13)C-Gram+)and fungi,which were the main active microorganisms mineralizing SOM.Microbial reproduction and growth were susceptible to nutrient availability.^(13)C-Gram+and^(13)C-fungi increased with Olsen P but decreased with dissolved organic carbon and NO−3 contents.In conclusion,biochar acts as an electron shuttle,stimulates iron reduction,and releases organic carbon from soil minerals,which in turn increases SOM mineralization.Gram+and fungi were involved in straw decomposition in response to biochar application and responsible for SOM mineralization.
