Lacustrine shale oil and gas are important fields for unconventional exploration and development in China,and organic-rich shale deposition lays down the critical foundation for hydrocarbon generation.There are two se...Lacustrine shale oil and gas are important fields for unconventional exploration and development in China,and organic-rich shale deposition lays down the critical foundation for hydrocarbon generation.There are two sets of shale,the Dongyuemiao and Da’anzhai Members,in the Ziliujing Formation in the Sichuan Basin.To identify the differential enrichment characteristics of organic matter and clarify its controlling factors,geochemical analyses of organic and inorganic geochemical analyses were performed.The results showed that the total organic carbon content of the Dongyuemiao shale(1.36%)is slightly higher than that of the Da’anzhai shale(0.95%).The enrichment of organic matter in the two shales resulted from the comprehensive controls of paleoproductivity,paleoenvironment,and terrigenous input,but different factors have different effects.In addition,driven by climate,the change in the sulfate concentration in the bottom water further led to the different intensities of bacterial sulfate reduction in early diagenesis.This made a great difference regarding organic matter accumulation in the two members.In general,climate may have played a dominant role in organic matter enrichment in the two sets of shale.展开更多
Soil organic matter(SOM)is the predominant component for sorption of hydrophobic organic compouds in soil and sorption by SOM ultimately affects chemical fate and availability in soil,and the degree of remedia- tion s...Soil organic matter(SOM)is the predominant component for sorption of hydrophobic organic compouds in soil and sorption by SOM ultimately affects chemical fate and availability in soil,and the degree of remedia- tion success of contaminated soils. This paper summarizes the latest development on sorption of organic com- pounds in soil (natural) organic matter,addresses four sorption mechanisms: surface adsorption,solid - phase Partitioning,dual-mode sorption,and fixed-pore sorption model,and presents future research directions as well.展开更多
Using multidiscipline methodologies, the differences in preservation and enrichment mechanisms of organic matter (OM) in muddy sediment and mudstone are investigated. In clay fractions, concentra- tions of TOC and chl...Using multidiscipline methodologies, the differences in preservation and enrichment mechanisms of organic matter (OM) in muddy sediment and mudstone are investigated. In clay fractions, concentra- tions of TOC and chloroform bitumen “A” are significantly higher than those in coarser fractions. This indicates that clay minerals (CM) play an important role in enriching OM. The content of chloroform bitumen “A” increases obviously in the clay fraction, which reveals that dissolvable OM is the main composition of coalesce with clay minerals. Furthermore, TG and DTA data show that OM enrichment mechanisms and preservation forms have multiplicity. Several exothermic peaks in the DTA curves demonstrate that muddy sediment and mudstone contain a number of bioclasts and amorphous OM besides dissolvable OM. Through analyzing with XRD and DTA after mudstone samples were pretreated, the conclusions can be arrived at. Firstly, CM interlayer space of XRD curves and exothermic peaks of DTA curves both change as temperature increases. Secondly, the changes of CM interlayer space and exothermic peaks are concordant and stable around 350℃. All these are the features that OM enters CM interlayers to form stable organo-clay complexes. Therefore, the combination format of OM with CM is not only surface adsorption, partial OM enters CM interlayers to form stable organo-clay complexes. Finally, through the research on OM preservation forms and enrichment mechanisms in muddy sedi- ment and mudstone, the hydrocarbon-generation processes and the global carbon cycle and budget can be explained.展开更多
Dissolved organic matter（DOM） is ubiquitous in the environment and has high reactivity.Once engineered nanoparticles（ENPs） are released into natural systems, interactions of DOM with ENPs may significantly affect ...Dissolved organic matter（DOM） is ubiquitous in the environment and has high reactivity.Once engineered nanoparticles（ENPs） are released into natural systems, interactions of DOM with ENPs may significantly affect the fate and transport of ENPs, as well as the bioavailability and toxicity of ENPs to organisms. However, because of the complexity of DOM and the shortage of useful characterization methods, large knowledge gaps exist in our understanding of the interactions between DOM and ENPs. In this article, we systematically reviewed the interactions between DOM and ENPs, discussed the effects of DOM on the environmental behavior of ENPs, and described the changes in bioavailability and toxicity of ENPs caused by DOM. Critical evaluations of published references suggest further need for assessing and predicting the influences of DOM on the transport,transformation, bioavailability, and toxicity of ENPs in the environment.展开更多
Sulfamethoxazole(SMX)is commonly detected in wastewater and cannot be completely decomposed during conventional treatment processes.Ozone(O_(3))is often used in water treatment.This study explored the influence of nat...Sulfamethoxazole(SMX)is commonly detected in wastewater and cannot be completely decomposed during conventional treatment processes.Ozone(O_(3))is often used in water treatment.This study explored the influence of natural organic matters(NOM)in secondary effluent of a sewage treatment plant on the ozonation pathways of SMX.The changes in NOM components during ozonation were also analyzed.SMX was primarily degraded by hydrolysis,isoxazole-ring opening,and double-bond addition,whereas hydroxylation was not the principal route given the low maximum abundances of the hydroxylated products,with m/z of 269 and 287.The hydroxylation process occurred mainly through indirect oxidation because the maximum abundances of the products reduced by about 70%after the radical quencher was added,whereas isoxazole-ring opening and double-bond addition processes mainly depended on direct oxidation,which was unaffected by the quencher.NOM mainly affected the degradation of micropollutants by consuming•OH rather than O_(3)molecules,resulting in the 63%–85%decrease in indirect oxidation products.The NOM in the effluent were also degraded simultaneously during ozonation,and the components with larger aromaticity were more likely degraded through direct oxidation.The dependences of the three main components of NOM in the effluent on indirect oxidation followed the sequence:humic-like substances>fluvic-like substance-s>protein-like substances.This study reveals the ozonation mechanism of SMX in secondary effluent and provides a theoretical basis for the control of SMX and its degradation products in actual water treatment.展开更多
Soil organic carbon(SOC)and nitrogen(N)mineralization are important biogeochemical processes associated with soil fertility.These processes are influenced by physically,chemically,and biologically stabilized SOC fract...Soil organic carbon(SOC)and nitrogen(N)mineralization are important biogeochemical processes associated with soil fertility.These processes are influenced by physically,chemically,and biologically stabilized SOC fractions,the mechanisms of which are not well known.The present study was conducted to evaluate the combined effect of manure and mineral fertilizers on the contents of SOC fractions to promote the mineralization of SOC and N.Treatments included:i)no fertilizer control(CK);ii)a combination of mineral N,phosphorus,and potassium fertilizers(NPK);iii)manure alone(M);iv)manure combined with NPK(MNPK);and v)a high dose of manure combined with NPK(hMNPK).The combined uses of manure and mineral fertilizers(MNPK and hMNPK)enhanced the accumulation of the unprotected coarse particulate organic carbon(C)fraction(cPOC)by 44%-72%compared to CK.Manure applications(M,MNPK and hMNPK)enhanced physically microaggregate-protected organic C(μagg),physicochemically protected organic C within the microaggregate-derived silt(μsilt)fraction(H-μsilt),and physicobiochemically protected organic C within theμsilt fraction(NH-μsilt)by 30%-56%,62%-150%,and 27%-51%,respectively.In contrast,all chemically and biochemically protected SOC fractions showed a minor response to manure application.Accumulation of cPOC,μagg,H-μsilt,and physicochemically protected organic C within the microaggregate-derived clay fraction(H-μclay)significantly contributed to the mineralization of SOC and N,resulting in a significant increase in rice grain yield with long-term manure application.In summary,long-term combined use of manure and mineral fertilizers improved SOC accumulation in unprotected and physically protected fractions,which enhanced SOC and N mineralization and benefited soil productivity in a rice-wheat cropping system.展开更多
基金This work was funded by the National Natural Science Foundation of China(Grant No.42002139 and U20B6001)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA14010404).
文摘Lacustrine shale oil and gas are important fields for unconventional exploration and development in China,and organic-rich shale deposition lays down the critical foundation for hydrocarbon generation.There are two sets of shale,the Dongyuemiao and Da’anzhai Members,in the Ziliujing Formation in the Sichuan Basin.To identify the differential enrichment characteristics of organic matter and clarify its controlling factors,geochemical analyses of organic and inorganic geochemical analyses were performed.The results showed that the total organic carbon content of the Dongyuemiao shale(1.36%)is slightly higher than that of the Da’anzhai shale(0.95%).The enrichment of organic matter in the two shales resulted from the comprehensive controls of paleoproductivity,paleoenvironment,and terrigenous input,but different factors have different effects.In addition,driven by climate,the change in the sulfate concentration in the bottom water further led to the different intensities of bacterial sulfate reduction in early diagenesis.This made a great difference regarding organic matter accumulation in the two members.In general,climate may have played a dominant role in organic matter enrichment in the two sets of shale.
文摘Soil organic matter(SOM)is the predominant component for sorption of hydrophobic organic compouds in soil and sorption by SOM ultimately affects chemical fate and availability in soil,and the degree of remedia- tion success of contaminated soils. This paper summarizes the latest development on sorption of organic com- pounds in soil (natural) organic matter,addresses four sorption mechanisms: surface adsorption,solid - phase Partitioning,dual-mode sorption,and fixed-pore sorption model,and presents future research directions as well.
基金Supported by the National Natural Science Foundation of China (Grant No. 40672085)China Petroleum and Chemical Corporation Project
文摘Using multidiscipline methodologies, the differences in preservation and enrichment mechanisms of organic matter (OM) in muddy sediment and mudstone are investigated. In clay fractions, concentra- tions of TOC and chloroform bitumen “A” are significantly higher than those in coarser fractions. This indicates that clay minerals (CM) play an important role in enriching OM. The content of chloroform bitumen “A” increases obviously in the clay fraction, which reveals that dissolvable OM is the main composition of coalesce with clay minerals. Furthermore, TG and DTA data show that OM enrichment mechanisms and preservation forms have multiplicity. Several exothermic peaks in the DTA curves demonstrate that muddy sediment and mudstone contain a number of bioclasts and amorphous OM besides dissolvable OM. Through analyzing with XRD and DTA after mudstone samples were pretreated, the conclusions can be arrived at. Firstly, CM interlayer space of XRD curves and exothermic peaks of DTA curves both change as temperature increases. Secondly, the changes of CM interlayer space and exothermic peaks are concordant and stable around 350℃. All these are the features that OM enters CM interlayers to form stable organo-clay complexes. Therefore, the combination format of OM with CM is not only surface adsorption, partial OM enters CM interlayers to form stable organo-clay complexes. Finally, through the research on OM preservation forms and enrichment mechanisms in muddy sedi- ment and mudstone, the hydrocarbon-generation processes and the global carbon cycle and budget can be explained.
基金supported by the National Key Research and Development Program of China (2016YFA0203102)the National Natural Science Foundation of China (Nos. 21227012, 21337004, 21507147)
文摘Dissolved organic matter（DOM） is ubiquitous in the environment and has high reactivity.Once engineered nanoparticles（ENPs） are released into natural systems, interactions of DOM with ENPs may significantly affect the fate and transport of ENPs, as well as the bioavailability and toxicity of ENPs to organisms. However, because of the complexity of DOM and the shortage of useful characterization methods, large knowledge gaps exist in our understanding of the interactions between DOM and ENPs. In this article, we systematically reviewed the interactions between DOM and ENPs, discussed the effects of DOM on the environmental behavior of ENPs, and described the changes in bioavailability and toxicity of ENPs caused by DOM. Critical evaluations of published references suggest further need for assessing and predicting the influences of DOM on the transport,transformation, bioavailability, and toxicity of ENPs in the environment.
基金This work was supported by the National Key Research and Development Project(No.2019YFD1100204).The experimental supporting by National Environmental and Energy Base for International Science&Technology Cooperation was greatly appreciated.
文摘Sulfamethoxazole(SMX)is commonly detected in wastewater and cannot be completely decomposed during conventional treatment processes.Ozone(O_(3))is often used in water treatment.This study explored the influence of natural organic matters(NOM)in secondary effluent of a sewage treatment plant on the ozonation pathways of SMX.The changes in NOM components during ozonation were also analyzed.SMX was primarily degraded by hydrolysis,isoxazole-ring opening,and double-bond addition,whereas hydroxylation was not the principal route given the low maximum abundances of the hydroxylated products,with m/z of 269 and 287.The hydroxylation process occurred mainly through indirect oxidation because the maximum abundances of the products reduced by about 70%after the radical quencher was added,whereas isoxazole-ring opening and double-bond addition processes mainly depended on direct oxidation,which was unaffected by the quencher.NOM mainly affected the degradation of micropollutants by consuming•OH rather than O_(3)molecules,resulting in the 63%–85%decrease in indirect oxidation products.The NOM in the effluent were also degraded simultaneously during ozonation,and the components with larger aromaticity were more likely degraded through direct oxidation.The dependences of the three main components of NOM in the effluent on indirect oxidation followed the sequence:humic-like substances>fluvic-like substance-s>protein-like substances.This study reveals the ozonation mechanism of SMX in secondary effluent and provides a theoretical basis for the control of SMX and its degradation products in actual water treatment.
基金supported by the National Natural Science Foundation of China(Nos.41877105,4190709398,and 41620104006)。
文摘Soil organic carbon(SOC)and nitrogen(N)mineralization are important biogeochemical processes associated with soil fertility.These processes are influenced by physically,chemically,and biologically stabilized SOC fractions,the mechanisms of which are not well known.The present study was conducted to evaluate the combined effect of manure and mineral fertilizers on the contents of SOC fractions to promote the mineralization of SOC and N.Treatments included:i)no fertilizer control(CK);ii)a combination of mineral N,phosphorus,and potassium fertilizers(NPK);iii)manure alone(M);iv)manure combined with NPK(MNPK);and v)a high dose of manure combined with NPK(hMNPK).The combined uses of manure and mineral fertilizers(MNPK and hMNPK)enhanced the accumulation of the unprotected coarse particulate organic carbon(C)fraction(cPOC)by 44%-72%compared to CK.Manure applications(M,MNPK and hMNPK)enhanced physically microaggregate-protected organic C(μagg),physicochemically protected organic C within the microaggregate-derived silt(μsilt)fraction(H-μsilt),and physicobiochemically protected organic C within theμsilt fraction(NH-μsilt)by 30%-56%,62%-150%,and 27%-51%,respectively.In contrast,all chemically and biochemically protected SOC fractions showed a minor response to manure application.Accumulation of cPOC,μagg,H-μsilt,and physicochemically protected organic C within the microaggregate-derived clay fraction(H-μclay)significantly contributed to the mineralization of SOC and N,resulting in a significant increase in rice grain yield with long-term manure application.In summary,long-term combined use of manure and mineral fertilizers improved SOC accumulation in unprotected and physically protected fractions,which enhanced SOC and N mineralization and benefited soil productivity in a rice-wheat cropping system.
