Asian dust has been identified in subtropical soils of China.Neodymium(Nd)and lead(Pb)elemental and isotopic geochemistry of soils in Southeast China were used to assess the significance of local versus extraneous sou...Asian dust has been identified in subtropical soils of China.Neodymium(Nd)and lead(Pb)elemental and isotopic geochemistry of soils in Southeast China were used to assess the significance of local versus extraneous sources.The εNd(0)values were close to the parent rocks(+2.9)in the young soils(NSJ);while their values were always negative(〜—3.7)in the old soils(OMJ),implying dust deposition.The young soils contained less Asian dust contribution(<8%)while the old soils contained more than 50%Asian dust contribution.This implied that dust contributions were gradually increasing with the soil development stage and Asian dust input had become the principal Nd source for the old soils in this area.On the other hand,Pb excesses and low 207Pb/206Pb values(〜0.8503)in near-surface soils indicated a significant anthropogenic Pb addition onto surface soils.The close relationship between the Pb content and isotopic ratios in the soil profile indicated that the excessive lead in the surface soil was exogenous.These results suggested that Asian dust made up a significant fraction in the old soils,but that local sources(i.e.,basalt and anthropogenic)were not trivial in Southeast China.展开更多
Utilization of biochar at high application rates can increase soil C and crop yields, decrease greenhouse gas emissions and reduce nutrient run-off from soils. However, the high application rate of 10 t ha-1 may not r...Utilization of biochar at high application rates can increase soil C and crop yields, decrease greenhouse gas emissions and reduce nutrient run-off from soils. However, the high application rate of 10 t ha-1 may not return a profit to the farmer due to the high cost of biochar. In this study biochar was modified through pre-treating the biomass and post-treating with phosphoric acid, minerals and different chemical fertilisers to study the effects of two new enhanced biochar fertilisers on the yield and quality of green pepper in a field experiment with 5 fertilisation treatments and 3 replications. The two new biochar fertilisers significantly （P 〈 0.05） increased the yield of green pepper （11.33-11.47 t ha-l）, compared with the conventional chemical fertiliser （9.72 t ha-l）. The biochar fertiliser treatments improved the vitamin C content of green pepper from 236.99 to 278.28 mg kg-1, and also significantly （P 〈 0.05） reduced the nitrate content from 132.32 to 101.92 mg kg-1, compared with chemical fertiliser. This study indicated that, compared to the use of conventional chemical fertiliser, all of the biochar fertiliser treatments could significantly improve the yield and quality of green pepper.展开更多
Globally,nitrogen(N)fertilizer demand is expected to reach 112 million tonnes to support food production for about 8 billion people.However,more than half of the N fertilizer is lost to the environment with impacts on...Globally,nitrogen(N)fertilizer demand is expected to reach 112 million tonnes to support food production for about 8 billion people.However,more than half of the N fertilizer is lost to the environment with impacts on air,water and soil quality,and biodiversity.Importantly,N loss to the environment contributes to greenhouse gas emissions and climate change.Nevertheless,where N fertilizer application is limited,severe depletion of soil fertility has become a major constraint to sustainable agriculture.To address the issues of low fertilizer N use efficiency(NUE),biochar-based N fertilizers(BBNFs)have been developed to reduce off-site loss and maximize crop N uptake.These products are generally made through physical mixing of biochar and N fertilizer or via coating chemical N fertilizers such as prilled urea with biochar.This review aims to describe the manufacturing processes of BBNFs,and to critically assess the effects of the products on soil properties,crop yield and N loss pathways.展开更多
Addition of biochar produced through thermal decomposition of biomass has been seen as a strategy to improve soils and to sequester carbon （C）, but wide scale implementation of the technology requires to devise inno...Addition of biochar produced through thermal decomposition of biomass has been seen as a strategy to improve soils and to sequester carbon （C）, but wide scale implementation of the technology requires to devise innovative profitable solutions. To develop biochar utilisation with an integrated system approach, an innovative program was implemented in 2012 on a 53-ha farm in Western Australia to determine the costs and benefits of integrating biochar with animal husbandry and improvement of pastures. Biochar was mixed with molasses and fed directly to cows. The dung-biochar mixture was incorporated into the soft profile by dung beetles. We studied the changes in soil properties over 3 years. Biochar extracted from fresh dung and from the soil to a depth of 40 cm was characterised. A preliminary financial analysis of the costs and benefits of this integrated approach was also undertaken. The preliminary investigation results suggested that this strategy was effective in improving soil properties and increasing returns to the farmer. It was also concluded that the biochar adsorbed nutrients from the cow＇s gut and from the dung. Dung beetles could transport this nutrient-rich biochar into the soil profile. There was little evidence that the recalcitrant component of the biochar was reduced through reactions inside the gut or on/in the soil. Further research is required to quantify the long-term impact of integrating biochar and dung beetles into the rearing of cows.展开更多
Dairy pastures can be a major source of soil nitrous oxide(N_(2)O)emissions due to the combination of intensive nitrogen(N)fertiliser use and high soil water content,from either rainfall and/or irrigation.Biochar appl...Dairy pastures can be a major source of soil nitrous oxide(N_(2)O)emissions due to the combination of intensive nitrogen(N)fertiliser use and high soil water content,from either rainfall and/or irrigation.Biochar application is a promising approach to lower soil greenhouse gas emissions,particularly under high soil moisture conditions where denitrification is the primary N-transformation pathway.In a replicated field trial,we evaluated the effects of two contrasting biochars derived from poul-try litter and from hardwood on soil N_(2)O emissions,soil ammonium(NH4^(+))and nitrate(NO3^(−))status,pasture productivity and herbage nutrient content.A liming treatment to mimic the liming equivalence of the poultry litter biochar was used to separate any effects observed from changes in soil pH.To further separate the effects of biochars on soil N status,N_(2)O emissions and pasture N uptake,high and low N fertiliser doses(annual application of 672 kg N ha^(−1),336 kg N ha^(−1))were superimposed across all of the treatments.The N fertiliser dose had no significant impact on pasture yield.Application of poultry litter biochar resulted in significant increases in pasture productivity under both high and low N inputs.This was achieved by alleviating soil P,and possibly K nutritional constraints that are typical in Australian Ferralsols.Under the high N fertiliser dose,emissions of N_(2)O from the treatments and control were not significantly different(p>0.05)and ranged between 1.14 and 1.78 kg N_(2)O-N ha^(−1)across the 11-month study.The low N dose resulted in significantly lower emissions of N_(2)O of between 0.80 and 0.84 kg N_(2)O-N ha^(−1),but biochar had no significant effect on net emissions across the season.The lack of impact of biochar on N_(2)O emissions was attributed to the relatively dry conditions over the trial period resulting in nitrification being the most likely N-transformation pathway.During brief episodes of high soil moisture,peak emissions from the biochar plots were lower than from the control or lime treatment,but these differences did not impact on the emis-sion budget over the 11-month sampling campaign.展开更多
The current study investigated the effect of biochars derived from cinnamomum woodchip,garden waste and mulberry woodchip on soil phytoavailable lead(Pb),cadmium(Cd)pools,and their uptake by Chinese cabbage(Brassica c...The current study investigated the effect of biochars derived from cinnamomum woodchip,garden waste and mulberry woodchip on soil phytoavailable lead(Pb),cadmium(Cd)pools,and their uptake by Chinese cabbage(Brassica chinensis L.).The biochars were produced at 450℃of pyrolysis temperature.The contaminated soils were collected from Yunfu(clas-sified as Udept),Jiyuan(Ustalf)and Shaoguan(Udult)cities in China at the depth of 0-20 cm and amended with biochars at the rate of 3%w/w.After mixing the soil with biochar for 14 days,the Chinese cabbage was planted in the amended soils.Then,it was harvested on the 48th day after sowing period.In Udult soil,Chinese cabbage died 18 days after sowing period in control and soils amended with cinnamomum and mulberry biochars.Although only plants grown with the garden waste biochar treatment survived in Udult soil,amendment of garden waste or mulberry biochars at 3%w/w(450℃)to Udult soil significantly increased(4.95-6.25)soil pH compared to other biochar treatments.In Udept and Ustalf soils,the application of garden waste and mulberry biochars significantly improved plant biomass compared to control,albeit it was dependent on both biochar and soil properties.Garden waste biochar significantly decreased soil Cd phytoavailable concentration by 26%in the Udult soil,while a decrease of soil Cd phytoavailable concentration by 16%and 9%was observed in Ustalf and Udept soils,respectively.The available phosphorus in biochar and soil pH were important factors controlling toxic metal phytouptake by the plant.Thus,the amendment of soil with biochar at 3%can effectively reduce the mobility of Cd and Pb in soil and plant uptake.However,biochar and soil properties should be well-known before being used for soil toxic metal immobilization.展开更多
基金the China Natural Science Foundation(Nos.41877006 and 41930862)we also express great thanks to Hailong Wang for his assistance in language polishing.
文摘Asian dust has been identified in subtropical soils of China.Neodymium(Nd)and lead(Pb)elemental and isotopic geochemistry of soils in Southeast China were used to assess the significance of local versus extraneous sources.The εNd(0)values were close to the parent rocks(+2.9)in the young soils(NSJ);while their values were always negative(〜—3.7)in the old soils(OMJ),implying dust deposition.The young soils contained less Asian dust contribution(<8%)while the old soils contained more than 50%Asian dust contribution.This implied that dust contributions were gradually increasing with the soil development stage and Asian dust input had become the principal Nd source for the old soils in this area.On the other hand,Pb excesses and low 207Pb/206Pb values(〜0.8503)in near-surface soils indicated a significant anthropogenic Pb addition onto surface soils.The close relationship between the Pb content and isotopic ratios in the soil profile indicated that the excessive lead in the surface soil was exogenous.These results suggested that Asian dust made up a significant fraction in the old soils,but that local sources(i.e.,basalt and anthropogenic)were not trivial in Southeast China.
基金financially supported by the Ministry of Science and Technology of China (Nos.2013GB23600666 and 2013BAD11B00)funded by the Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization,China+1 种基金supported by the grant of the Australian Research Council (No.LP120200418)Renewed Carbon Pty Ltd.,Australia and the project of DAFF Carbon Farming Futures-Filling the Research Gap,Australia (No.RG134978)
文摘Utilization of biochar at high application rates can increase soil C and crop yields, decrease greenhouse gas emissions and reduce nutrient run-off from soils. However, the high application rate of 10 t ha-1 may not return a profit to the farmer due to the high cost of biochar. In this study biochar was modified through pre-treating the biomass and post-treating with phosphoric acid, minerals and different chemical fertilisers to study the effects of two new enhanced biochar fertilisers on the yield and quality of green pepper in a field experiment with 5 fertilisation treatments and 3 replications. The two new biochar fertilisers significantly （P 〈 0.05） increased the yield of green pepper （11.33-11.47 t ha-l）, compared with the conventional chemical fertiliser （9.72 t ha-l）. The biochar fertiliser treatments improved the vitamin C content of green pepper from 236.99 to 278.28 mg kg-1, and also significantly （P 〈 0.05） reduced the nitrate content from 132.32 to 101.92 mg kg-1, compared with chemical fertiliser. This study indicated that, compared to the use of conventional chemical fertiliser, all of the biochar fertiliser treatments could significantly improve the yield and quality of green pepper.
基金the National Natural Science Foundation of China(21876027)Science and Technology Innovation Project Guangdong Province(2019KQNCX169)+1 种基金the Key Scientific and Technological Project of Foshan City,China(2120001008392)the Science and Technology Innovation Project of Foshan,China(1920001000083).
文摘Globally,nitrogen(N)fertilizer demand is expected to reach 112 million tonnes to support food production for about 8 billion people.However,more than half of the N fertilizer is lost to the environment with impacts on air,water and soil quality,and biodiversity.Importantly,N loss to the environment contributes to greenhouse gas emissions and climate change.Nevertheless,where N fertilizer application is limited,severe depletion of soil fertility has become a major constraint to sustainable agriculture.To address the issues of low fertilizer N use efficiency(NUE),biochar-based N fertilizers(BBNFs)have been developed to reduce off-site loss and maximize crop N uptake.These products are generally made through physical mixing of biochar and N fertilizer or via coating chemical N fertilizers such as prilled urea with biochar.This review aims to describe the manufacturing processes of BBNFs,and to critically assess the effects of the products on soil properties,crop yield and N loss pathways.
基金funded by the Linkage,Infrastructure,Equipment and Facilities (LIEF) grant from the Australian Research Council (ARC) (No.LE120100104)supported by the ARC (No.LP120200418),Renewed Carbon Pty Ltd.of Australiathe Department of Agriculture,Australian Government’s Carbon Farming Futures Filling the Research Gap (No.RG134978)
文摘Addition of biochar produced through thermal decomposition of biomass has been seen as a strategy to improve soils and to sequester carbon （C）, but wide scale implementation of the technology requires to devise innovative profitable solutions. To develop biochar utilisation with an integrated system approach, an innovative program was implemented in 2012 on a 53-ha farm in Western Australia to determine the costs and benefits of integrating biochar with animal husbandry and improvement of pastures. Biochar was mixed with molasses and fed directly to cows. The dung-biochar mixture was incorporated into the soft profile by dung beetles. We studied the changes in soil properties over 3 years. Biochar extracted from fresh dung and from the soil to a depth of 40 cm was characterised. A preliminary financial analysis of the costs and benefits of this integrated approach was also undertaken. The preliminary investigation results suggested that this strategy was effective in improving soil properties and increasing returns to the farmer. It was also concluded that the biochar adsorbed nutrients from the cow＇s gut and from the dung. Dung beetles could transport this nutrient-rich biochar into the soil profile. There was little evidence that the recalcitrant component of the biochar was reduced through reactions inside the gut or on/in the soil. Further research is required to quantify the long-term impact of integrating biochar and dung beetles into the rearing of cows.
文摘Dairy pastures can be a major source of soil nitrous oxide(N_(2)O)emissions due to the combination of intensive nitrogen(N)fertiliser use and high soil water content,from either rainfall and/or irrigation.Biochar application is a promising approach to lower soil greenhouse gas emissions,particularly under high soil moisture conditions where denitrification is the primary N-transformation pathway.In a replicated field trial,we evaluated the effects of two contrasting biochars derived from poul-try litter and from hardwood on soil N_(2)O emissions,soil ammonium(NH4^(+))and nitrate(NO3^(−))status,pasture productivity and herbage nutrient content.A liming treatment to mimic the liming equivalence of the poultry litter biochar was used to separate any effects observed from changes in soil pH.To further separate the effects of biochars on soil N status,N_(2)O emissions and pasture N uptake,high and low N fertiliser doses(annual application of 672 kg N ha^(−1),336 kg N ha^(−1))were superimposed across all of the treatments.The N fertiliser dose had no significant impact on pasture yield.Application of poultry litter biochar resulted in significant increases in pasture productivity under both high and low N inputs.This was achieved by alleviating soil P,and possibly K nutritional constraints that are typical in Australian Ferralsols.Under the high N fertiliser dose,emissions of N_(2)O from the treatments and control were not significantly different(p>0.05)and ranged between 1.14 and 1.78 kg N_(2)O-N ha^(−1)across the 11-month study.The low N dose resulted in significantly lower emissions of N_(2)O of between 0.80 and 0.84 kg N_(2)O-N ha^(−1),but biochar had no significant effect on net emissions across the season.The lack of impact of biochar on N_(2)O emissions was attributed to the relatively dry conditions over the trial period resulting in nitrification being the most likely N-transformation pathway.During brief episodes of high soil moisture,peak emissions from the biochar plots were lower than from the control or lime treatment,but these differences did not impact on the emis-sion budget over the 11-month sampling campaign.
基金The financial supports from Special fund for Agricultural competitive industry discipline team building project of Guangdong Academy of Agricultural Sciences(202120TD)Guangdong Academy of Agricultural Sciences Dean Fund,China(BZ201903,BZ202001)+3 种基金Natural Science Foundation of China(41571313,21876027)Department of Science and Technology of Guangdong Province,China(2019B121201003)The National Project for Agricultural Technology System(CARS-18)Guangdong Provincial Special Fund For Modern Agriculture Industry Technology Innovation Teams(2019KJ109,2019KJ148)are gratefully acknowledged.
文摘The current study investigated the effect of biochars derived from cinnamomum woodchip,garden waste and mulberry woodchip on soil phytoavailable lead(Pb),cadmium(Cd)pools,and their uptake by Chinese cabbage(Brassica chinensis L.).The biochars were produced at 450℃of pyrolysis temperature.The contaminated soils were collected from Yunfu(clas-sified as Udept),Jiyuan(Ustalf)and Shaoguan(Udult)cities in China at the depth of 0-20 cm and amended with biochars at the rate of 3%w/w.After mixing the soil with biochar for 14 days,the Chinese cabbage was planted in the amended soils.Then,it was harvested on the 48th day after sowing period.In Udult soil,Chinese cabbage died 18 days after sowing period in control and soils amended with cinnamomum and mulberry biochars.Although only plants grown with the garden waste biochar treatment survived in Udult soil,amendment of garden waste or mulberry biochars at 3%w/w(450℃)to Udult soil significantly increased(4.95-6.25)soil pH compared to other biochar treatments.In Udept and Ustalf soils,the application of garden waste and mulberry biochars significantly improved plant biomass compared to control,albeit it was dependent on both biochar and soil properties.Garden waste biochar significantly decreased soil Cd phytoavailable concentration by 26%in the Udult soil,while a decrease of soil Cd phytoavailable concentration by 16%and 9%was observed in Ustalf and Udept soils,respectively.The available phosphorus in biochar and soil pH were important factors controlling toxic metal phytouptake by the plant.Thus,the amendment of soil with biochar at 3%can effectively reduce the mobility of Cd and Pb in soil and plant uptake.However,biochar and soil properties should be well-known before being used for soil toxic metal immobilization.
