Subtropical recent alluvial soils are low in organic carbon(C).Thus,increasing organic C is a major challenge to sustain soil fertility.Biochar amendment could be an option as biochar is a C-rich pyrolyzed material,wh...Subtropical recent alluvial soils are low in organic carbon(C).Thus,increasing organic C is a major challenge to sustain soil fertility.Biochar amendment could be an option as biochar is a C-rich pyrolyzed material,which is slowly decomposed in soil.We investigated C mineralization(CO_(2)-C evolution)in two types of soils(recent and old alluvial soils)amended with two feedstocks(sugarcane bagasse and rice husk)(1%,weight/weight),as well as their biochars and aged biochars under a controlled environment(25±2℃)over 85 d.For the recent alluvial soil(charland soil),the highest absolute cumulative CO_(2)-C evolution was observed in the sugarcane bagasse treatment(1140 mg CO_(2)-C kg^(-1)soil)followed by the rice husk treatment(1090 mg CO_(2)-C kg^(-1)soil);the lowest amount(150 mg CO_(2)-C kg^(-1)soil)was observed in the aged rice husk biochar treatment.Similarly,for the old alluvial soil(farmland soil),the highest absolute cumulative CO_(2)-C evolution(1290 mg CO_(2)-C kg^(-1)soil)was observed in the sugarcane bagasse treatment and then in the rice husk treatment(1270 mg CO_(2)-C kg^(-1)soil);the lowest amount(200 mg CO_(2)-C kg^(-1)soil)was in the aged rice husk biochar treatment.Aged sugarcane bagasse and rice husk biochar treatments reduced absolute cumulative CO_(2)-C evolution by 10%and 36%,respectively,compared with unamended recent alluvial soil,and by 10%and 18%,respectively,compared with unamended old alluvial soil.Both absolute and normalized C mineralization were similar between the sugarcane bagasse and rice husk treatments,between the biochar treatments,and between the aged biochar treatments.In both soils,the feedstock treatments resulted in the highest cumulative CO_(2)-C evolution,followed by the biochar treatments and then the aged biochar treatments.The absolute and normalized CO_(2)-C evolution and the mineralization rate constant of the stable C pool(K_(s))were lower in the recent alluvial soil compared with those in the old alluvial soil.The biochars and aged biochars had a negative priming effect in both soils,but the effect was more prominent in the recent alluvial soil.These results would have good implications for improving organic matter content in organic C-poor alluvial soils.展开更多
The individual and combined effects of biochar(B)and inorganic fertiliser(F)have all been widely proofed to improve soil fertility and enhance crop growth and yield under irrigation(I)and rain fed conditions.However,t...The individual and combined effects of biochar(B)and inorganic fertiliser(F)have all been widely proofed to improve soil fertility and enhance crop growth and yield under irrigation(I)and rain fed conditions.However,the strength of their individual and combined effects on crop productivity has been scarcely reported.In addition,few studies have assessed their individual and co-application effects on economic returns.Therefore,a 2-year field experiment which consisted of factorial combination of irrigation(I)[100%full irrigation(FI),80%FI and 60%FI],biochar(0 and 20 t/ha)and fertiliser(0 and 300 kg/ha)was conducted.According to the results,irrigation was the dominant factor that influences maize grain yield,followed by inorganic fertiliser and biochar,and they were all significant in their main effects.The strength of interaction effects among,I,F and B on maize grain yield follow the sequence F×I>B×F>B×I.The economic analysis showed that the ternary combination of B,F and I was more economical than the binary combination of B plus I,and F plus I(in that order),when compared with the standalone application of I at maximum production in the field experiment.In addition,combined applications of biochar and fertiliser improved soil nutrients,nutrient uptake in all irrigation treatments,compared to the standalone applications of biochar or fertiliser.Further research is,therefore,recommended for long-term evaluation of the economic viability of integrating biochar with fertiliser under irrigation.展开更多
Biochar and dung amendments have been extensively employed in soil remediation and fertilization of grasslands,which are the largest terrestrial sinks for methane.However,how these exogenous amendments regulate methan...Biochar and dung amendments have been extensively employed in soil remediation and fertilization of grasslands,which are the largest terrestrial sinks for methane.However,how these exogenous amendments regulate methane metabolisms at the molecular and community levels remains elusive.In this study,we investigated the functional genes and community assemblies of methanogens and methanotrophs using Geochip 5.0 and high-throughput sequencing to reveal the impacts of biochar and dung on soil methanogenesis and methane oxidation.The interac-tions between methane metabolic genes and other biogeochemical genes were also examined.According to Geo-chip microarrays,methanogenic gene mcrA decreased and increased with dung or biochar amendment,respectively;The methanotrophic gene pmoA showed a reverse but not significant tendency.Undominated processes contributed 65.51%to replace homogeneous selections as primary driving forces of methanogen assembly after dung amend-ment;the contribution of dispersal limitation increased to 46.13%in methanotroph assembly after biochar amend-ment.The diversity and association of co-occurrence networks for carbon-nitrogen cycling genes decreased after exogenous amendments.These results indicated that biochar and dung amendments prominently regulated the functional genes and community assembly involved in methane metabolisms.The co-existence patterns of methane metabolic genes and other related geochemical genes were also shaped by these amendments.This study provides the scientific reference for the development of grassland management in the context of global warming.展开更多
The residue of atrazine in field soils poses a major threat to crop growth in the rotation system,raising concerns about grain security and food safety.Current agricultural production requires more efficient and cost-...The residue of atrazine in field soils poses a major threat to crop growth in the rotation system,raising concerns about grain security and food safety.Current agricultural production requires more efficient and cost-effective mitigation measures in response to the emerging threat.This study reported the critical concentration(0.1 mg L^(−1))of atrazine injury to soybean seedlings in soil pore water and how biochar amendment could influence the distribution of atrazine in different soil environments.The results showed that biochar significantly reduced the concentration of atrazine in soil pore water,for example,0.5%biochar in red(cinnamon,fluvo-aquic,paddy,black)soil reduced atrazine concentration from 0.31(0.20,0.18,0.12,0.03)mg L^(−1)to 0.004(0.002,0.005,0.013,0.011)mg L^(−1)in pore water(P<0.01).On the basis of these,a reliable mathematical model was developed to predict the atrazine concentration in soil pore water under(or without)biochar amendment conditions.The verification results showed that the mean absolute percentage error of the model was 14.1%,indicating that the prediction error was within a reasonable range.Our work provides a precise solution to crop injury caused by soil residual herbicides with the aid of biochar,which reduces the bioavailability of atrazine in soybean seedlings.This method not only maximizes the use of biochar but also provides effective crop protection and environmental benefits.展开更多
Biochar as an organic amendment improves soil attributes,with a potentially significant effect on soil chemical fertility and quality.The main objective of this study was to quantify the effect of biochar addition on ...Biochar as an organic amendment improves soil attributes,with a potentially significant effect on soil chemical fertility and quality.The main objective of this study was to quantify the effect of biochar addition on nutrients,carbon sequestra-tion and microbial activity and understand the mechanisms of controlling biochar effects in calcareous soils.Maize residue biochars produced at 200,400 and 600℃ were added at 5 and 10 g kg^(−1)rates to sandy loam and clayey texture calcareous soils.The soil properties measured were pH and electrical conductivity(EC),plant-available potassium(K)and available phosphorus(P),total nitrogen(TN),C sequestration;and the fluorescein diacetate(FDA)hydrolysis activity.Addition of raw material and biochars increased pH(0.15-0.46 units),EC(0.14-0.38 dS m^(−1)),TN(63-120%),K(12-41%)and FDA activity(27-280%),but tended to decrease plant-available P(23-86%).Increasing pyrolysis temperature increased soil C pool index(CPI),but decreased the FDA and the changes depended largely upon the application rate and soil texture.The positive effects of biochar addition and its pyrolysis temperature on soil C sequestration potential were more pronounced at high than low application rate and in sandy loam than clayey soils.Nevertheless,the effect of biochar addition and pyrolysis temperature on the FDA activity was higher at high than low application rates,but lower in sandy loam than clayey soils.Although biochar application may successfully improve soil processes and attributes and have a high potential for C seques-tration,its effects are controlled by soil texture,pyrolysis temperature and application rate.展开更多
Biochar applications have an enormous impact on the soil microbial community and functionality.However,the majority of the knowledge on biochar-microbe interaction derives almost exclusively from bacterial and fungal ...Biochar applications have an enormous impact on the soil microbial community and functionality.However,the majority of the knowledge on biochar-microbe interaction derives almost exclusively from bacterial and fungal studies,while the vast majority of eukaryotic diversity,protists,are mostly neglected.Protists play important roles in the soil ecosystem as microbial predators,decomposers,photoautotrophs,pathogens,and parasites and they are essential for a healthy soil ecosystem.Toward a comprehensive understanding of the effects of biochar application,we need more studies on protists across the full breadth of eukaryotic diversity.The aim of this article is to highlight the research needs and discuss potential research ideas on biochar-protist interaction,which would advance our knowledge of biochar-microbe interaction.展开更多
Biochar amendment and substituting chemical fertilizers with organic manure(organic substitution)have been widely reported to increase crop production and decrease reactive nitrogen(Nr)loss including nitrous oxide(N_(...Biochar amendment and substituting chemical fertilizers with organic manure(organic substitution)have been widely reported to increase crop production and decrease reactive nitrogen(Nr)loss including nitrous oxide(N_(2)O),nitric oxide(NO),and ammonia(NH3)emissions,and N runoff and leaching.However,few comprehensive evalua-tions have been performed on the environmental and economic aspects of biochar amendment or organic sub-stitution.Here,we studied the comprehensive effects of biochar amendment,organic substitution,and biochar amendment combined with organic substitution on crop production,Nr loss,and net ecosystem economic benefit(NEEB)in intensive vegetable production by integrating life-cycle assessment for Nr footprints,empirical models for NH3 volatilization and N runoff and leaching derived from peer-reviewed publications and validated by the current measurements and direct field measurement for N_(2)O and NO emissions during 5 consecutive years of vegetable crop rotations.Five fertilization treatments were applied(SN:synthetic fertilizer application;SNB:SN plus 20 t ha^(−1)biochar amendment;SNM:substituting 50%of chemical N fertilizer with organic manure;SNMB:SNM plus 20 t ha^(−1)biochar amendment;and CK:no fertilizer or biochar addition).Compared with the SN,the SNB increased vegetable yield(28.4%,p<0.05;interannually varying from−10 to 74.9%)and nitrogen use efficiency(29.2%,interannually varying from−39.7 to 150.4%),and decreased field Nr loss(45.4%,p<0.01;interannually varying from−40.3 to 78.4%),and thus improved NEEB by 7.1%;meanwhile,the SNM increased vegetable yield(11.6%,interannually varying from−5.4 to 27.1%)and nitrogen use efficiency(45.7%,p<0.05;interannually varying from 2.3 to 154%),reduced field Nr loss(34.9%,p<0.01;interannually varying from 8.4-39.0%),and thus improved NEEB by 17.8%(p<0.05)compared to the SN,being 56.0×10^(3)Chinese Yuan(CNY)ha^(−1)crop^(−1).Due to the high foreground Nr loss during organic manure production and high input costs of biochar production,the SNMB decreased the NEEB by 8.0%as compared to the SN.Moreover,the SNB and SNM improved vegetable qualities by increasing protein,soluble sugar,and vitamin C contents while decreasing nitrate content(p<0.05).Therefore,single application of biochar amendment or organic substitution would achieve better NEEB and product quality in vegetable production.展开更多
基金the BARC(Bangladesh Agricultural Research Council)for awarding a postgraduate scholarship with research support to the first author through the NATP(National Agricultural Technology Program)Phase-ⅡProject。
文摘Subtropical recent alluvial soils are low in organic carbon(C).Thus,increasing organic C is a major challenge to sustain soil fertility.Biochar amendment could be an option as biochar is a C-rich pyrolyzed material,which is slowly decomposed in soil.We investigated C mineralization(CO_(2)-C evolution)in two types of soils(recent and old alluvial soils)amended with two feedstocks(sugarcane bagasse and rice husk)(1%,weight/weight),as well as their biochars and aged biochars under a controlled environment(25±2℃)over 85 d.For the recent alluvial soil(charland soil),the highest absolute cumulative CO_(2)-C evolution was observed in the sugarcane bagasse treatment(1140 mg CO_(2)-C kg^(-1)soil)followed by the rice husk treatment(1090 mg CO_(2)-C kg^(-1)soil);the lowest amount(150 mg CO_(2)-C kg^(-1)soil)was observed in the aged rice husk biochar treatment.Similarly,for the old alluvial soil(farmland soil),the highest absolute cumulative CO_(2)-C evolution(1290 mg CO_(2)-C kg^(-1)soil)was observed in the sugarcane bagasse treatment and then in the rice husk treatment(1270 mg CO_(2)-C kg^(-1)soil);the lowest amount(200 mg CO_(2)-C kg^(-1)soil)was in the aged rice husk biochar treatment.Aged sugarcane bagasse and rice husk biochar treatments reduced absolute cumulative CO_(2)-C evolution by 10%and 36%,respectively,compared with unamended recent alluvial soil,and by 10%and 18%,respectively,compared with unamended old alluvial soil.Both absolute and normalized C mineralization were similar between the sugarcane bagasse and rice husk treatments,between the biochar treatments,and between the aged biochar treatments.In both soils,the feedstock treatments resulted in the highest cumulative CO_(2)-C evolution,followed by the biochar treatments and then the aged biochar treatments.The absolute and normalized CO_(2)-C evolution and the mineralization rate constant of the stable C pool(K_(s))were lower in the recent alluvial soil compared with those in the old alluvial soil.The biochars and aged biochars had a negative priming effect in both soils,but the effect was more prominent in the recent alluvial soil.These results would have good implications for improving organic matter content in organic C-poor alluvial soils.
基金We appreciate the research grant from the Tertiary Education Trust Fund(TETFUND)Nigeria,which was used to fund part of this research.
文摘The individual and combined effects of biochar(B)and inorganic fertiliser(F)have all been widely proofed to improve soil fertility and enhance crop growth and yield under irrigation(I)and rain fed conditions.However,the strength of their individual and combined effects on crop productivity has been scarcely reported.In addition,few studies have assessed their individual and co-application effects on economic returns.Therefore,a 2-year field experiment which consisted of factorial combination of irrigation(I)[100%full irrigation(FI),80%FI and 60%FI],biochar(0 and 20 t/ha)and fertiliser(0 and 300 kg/ha)was conducted.According to the results,irrigation was the dominant factor that influences maize grain yield,followed by inorganic fertiliser and biochar,and they were all significant in their main effects.The strength of interaction effects among,I,F and B on maize grain yield follow the sequence F×I>B×F>B×I.The economic analysis showed that the ternary combination of B,F and I was more economical than the binary combination of B plus I,and F plus I(in that order),when compared with the standalone application of I at maximum production in the field experiment.In addition,combined applications of biochar and fertiliser improved soil nutrients,nutrient uptake in all irrigation treatments,compared to the standalone applications of biochar or fertiliser.Further research is,therefore,recommended for long-term evaluation of the economic viability of integrating biochar with fertiliser under irrigation.
基金the National Key Research and Development Program of China(No.2018YFD0800403).
文摘Biochar and dung amendments have been extensively employed in soil remediation and fertilization of grasslands,which are the largest terrestrial sinks for methane.However,how these exogenous amendments regulate methane metabolisms at the molecular and community levels remains elusive.In this study,we investigated the functional genes and community assemblies of methanogens and methanotrophs using Geochip 5.0 and high-throughput sequencing to reveal the impacts of biochar and dung on soil methanogenesis and methane oxidation.The interac-tions between methane metabolic genes and other biogeochemical genes were also examined.According to Geo-chip microarrays,methanogenic gene mcrA decreased and increased with dung or biochar amendment,respectively;The methanotrophic gene pmoA showed a reverse but not significant tendency.Undominated processes contributed 65.51%to replace homogeneous selections as primary driving forces of methanogen assembly after dung amend-ment;the contribution of dispersal limitation increased to 46.13%in methanotroph assembly after biochar amend-ment.The diversity and association of co-occurrence networks for carbon-nitrogen cycling genes decreased after exogenous amendments.These results indicated that biochar and dung amendments prominently regulated the functional genes and community assembly involved in methane metabolisms.The co-existence patterns of methane metabolic genes and other related geochemical genes were also shaped by these amendments.This study provides the scientific reference for the development of grassland management in the context of global warming.
基金supported by the National Key Research and Development Program of China(No.2023YFD1701305)the National Natural Science Foundation of China(NSFC 32261133527).
文摘The residue of atrazine in field soils poses a major threat to crop growth in the rotation system,raising concerns about grain security and food safety.Current agricultural production requires more efficient and cost-effective mitigation measures in response to the emerging threat.This study reported the critical concentration(0.1 mg L^(−1))of atrazine injury to soybean seedlings in soil pore water and how biochar amendment could influence the distribution of atrazine in different soil environments.The results showed that biochar significantly reduced the concentration of atrazine in soil pore water,for example,0.5%biochar in red(cinnamon,fluvo-aquic,paddy,black)soil reduced atrazine concentration from 0.31(0.20,0.18,0.12,0.03)mg L^(−1)to 0.004(0.002,0.005,0.013,0.011)mg L^(−1)in pore water(P<0.01).On the basis of these,a reliable mathematical model was developed to predict the atrazine concentration in soil pore water under(or without)biochar amendment conditions.The verification results showed that the mean absolute percentage error of the model was 14.1%,indicating that the prediction error was within a reasonable range.Our work provides a precise solution to crop injury caused by soil residual herbicides with the aid of biochar,which reduces the bioavailability of atrazine in soybean seedlings.This method not only maximizes the use of biochar but also provides effective crop protection and environmental benefits.
基金We express our thanks to Shahrekord University for providing the financial support under the grant of 93GCU2M1932。
文摘Biochar as an organic amendment improves soil attributes,with a potentially significant effect on soil chemical fertility and quality.The main objective of this study was to quantify the effect of biochar addition on nutrients,carbon sequestra-tion and microbial activity and understand the mechanisms of controlling biochar effects in calcareous soils.Maize residue biochars produced at 200,400 and 600℃ were added at 5 and 10 g kg^(−1)rates to sandy loam and clayey texture calcareous soils.The soil properties measured were pH and electrical conductivity(EC),plant-available potassium(K)and available phosphorus(P),total nitrogen(TN),C sequestration;and the fluorescein diacetate(FDA)hydrolysis activity.Addition of raw material and biochars increased pH(0.15-0.46 units),EC(0.14-0.38 dS m^(−1)),TN(63-120%),K(12-41%)and FDA activity(27-280%),but tended to decrease plant-available P(23-86%).Increasing pyrolysis temperature increased soil C pool index(CPI),but decreased the FDA and the changes depended largely upon the application rate and soil texture.The positive effects of biochar addition and its pyrolysis temperature on soil C sequestration potential were more pronounced at high than low application rate and in sandy loam than clayey soils.Nevertheless,the effect of biochar addition and pyrolysis temperature on the FDA activity was higher at high than low application rates,but lower in sandy loam than clayey soils.Although biochar application may successfully improve soil processes and attributes and have a high potential for C seques-tration,its effects are controlled by soil texture,pyrolysis temperature and application rate.
基金the Japan Society for the Promotion of Science(JSPS)to Asiloglu R(Grant No.JP22K14804).
文摘Biochar applications have an enormous impact on the soil microbial community and functionality.However,the majority of the knowledge on biochar-microbe interaction derives almost exclusively from bacterial and fungal studies,while the vast majority of eukaryotic diversity,protists,are mostly neglected.Protists play important roles in the soil ecosystem as microbial predators,decomposers,photoautotrophs,pathogens,and parasites and they are essential for a healthy soil ecosystem.Toward a comprehensive understanding of the effects of biochar application,we need more studies on protists across the full breadth of eukaryotic diversity.The aim of this article is to highlight the research needs and discuss potential research ideas on biochar-protist interaction,which would advance our knowledge of biochar-microbe interaction.
基金the National Natural Science Foundation of China(41977078,32001213)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(KYCX21_0618,KYCX20_0591).
文摘Biochar amendment and substituting chemical fertilizers with organic manure(organic substitution)have been widely reported to increase crop production and decrease reactive nitrogen(Nr)loss including nitrous oxide(N_(2)O),nitric oxide(NO),and ammonia(NH3)emissions,and N runoff and leaching.However,few comprehensive evalua-tions have been performed on the environmental and economic aspects of biochar amendment or organic sub-stitution.Here,we studied the comprehensive effects of biochar amendment,organic substitution,and biochar amendment combined with organic substitution on crop production,Nr loss,and net ecosystem economic benefit(NEEB)in intensive vegetable production by integrating life-cycle assessment for Nr footprints,empirical models for NH3 volatilization and N runoff and leaching derived from peer-reviewed publications and validated by the current measurements and direct field measurement for N_(2)O and NO emissions during 5 consecutive years of vegetable crop rotations.Five fertilization treatments were applied(SN:synthetic fertilizer application;SNB:SN plus 20 t ha^(−1)biochar amendment;SNM:substituting 50%of chemical N fertilizer with organic manure;SNMB:SNM plus 20 t ha^(−1)biochar amendment;and CK:no fertilizer or biochar addition).Compared with the SN,the SNB increased vegetable yield(28.4%,p<0.05;interannually varying from−10 to 74.9%)and nitrogen use efficiency(29.2%,interannually varying from−39.7 to 150.4%),and decreased field Nr loss(45.4%,p<0.01;interannually varying from−40.3 to 78.4%),and thus improved NEEB by 7.1%;meanwhile,the SNM increased vegetable yield(11.6%,interannually varying from−5.4 to 27.1%)and nitrogen use efficiency(45.7%,p<0.05;interannually varying from 2.3 to 154%),reduced field Nr loss(34.9%,p<0.01;interannually varying from 8.4-39.0%),and thus improved NEEB by 17.8%(p<0.05)compared to the SN,being 56.0×10^(3)Chinese Yuan(CNY)ha^(−1)crop^(−1).Due to the high foreground Nr loss during organic manure production and high input costs of biochar production,the SNMB decreased the NEEB by 8.0%as compared to the SN.Moreover,the SNB and SNM improved vegetable qualities by increasing protein,soluble sugar,and vitamin C contents while decreasing nitrate content(p<0.05).Therefore,single application of biochar amendment or organic substitution would achieve better NEEB and product quality in vegetable production.
