Effect-of-dissolved-organic-matter-from-Guangzhou-landfill-leachate-on-sorption-of-phenanthrene-by-M

土壤有机碳激发效应英文回答：Soil organic carbon (SOC) plays a crucial role in maintaining the productivity and health of terrestrial ecosystems. Enhancing SOC content has emerged as a promising strategy to improve soil quality and mitigate the effects of climate change. This phenomenon, known as the "priming effect," involves the acceleration of decomposition of native soil organic matter (SOM) upon the addition of fresh organic matter inputs.The priming effect is driven by the microbial response to the increased availability of labile carbon from the fresh organic matter. Microbes utilize this labile carbon as an energy source, releasing enzymes that degrade both the fresh organic matter and native SOM. The extent of the priming effect varies depending on the quality of the added organic matter, the soil microbial community composition, and environmental conditions.Several mechanisms have been proposed to explain the priming effect. One theory suggests that the addition of fresh organic matter stimulates the growth of microbial populations, leading to increased enzyme production and decomposition of both the fresh and native SOM. Another mechanism involves the selective utilization of labile carbon by microbes, leaving behind more recalcitrant compounds that are more resistant to decomposition. This process can result in the accumulation of recalcitrant organic matter, which can have long-term effects on soil carbon dynamics.The priming effect can have both positive and negative implications for soil health and ecosystem functioning. On the one hand, it can accelerate the release of nutrients from SOM, making them available for plant uptake. This increased nutrient availability can boost plant growth and productivity. On the other hand, the priming effect can also lead to the loss of stable SOC, which is an important component of soil carbon storage and a major contributor to the global carbon cycle.Managing the priming effect is crucial for sustainable soil management practices. One approach involves the use of organic matter amendments that are high in labile carbonand low in recalcitrant compounds. This can help tominimize the loss of stable SOC while still stimulating microbial activity and nutrient release. Additionally, maintaining a diverse soil microbial community can promote the balanced decomposition of organic matter and reduce the risk of excessive priming.中文回答：土壤有机碳（SOC）在维持陆地生态系统的生产力和健康方面发挥着至关重要的作用。

江福林，卢云浩，何强. 茶多酚对植物乳杆菌、金黄色葡萄球菌和大肠杆菌生长的双向调节作用[J]. 食品工业科技，2023，44（22）：152−159. doi: 10.13386/j.issn1002-0306.2023040081JIANG Fulin, LU Yunhao, HE Qiang. Dual-directional Regulation of Tea Polyphenols on the Growth of Lactobacillus plantarum ,Staphylococcus aureus , and Escherichia coli [J]. Science and Technology of Food Industry, 2023, 44(22): 152−159. (in Chinese with English abstract). doi: 10.13386/j.issn1002-0306.2023040081· 生物工程 ·茶多酚对植物乳杆菌、金黄色葡萄球菌和大肠杆菌生长的双向调节作用江福林1，卢云浩2，何　强1,*（1.四川大学轻工科学与工程学院，四川成都 610065；2.成都大学食品与生物工程学院，四川成都 610106）摘　要：增强益生菌产品中益生菌的活力，同时抑制食源性致病菌及腐败菌的生长能够提升产品品质稳定性。

在单培养及共培养条件下，采用传统计数法和高通量测序比较研究了不同浓度的茶多酚对益生菌植物乳杆菌、致病菌金黄色葡萄球菌和大肠杆菌生长的影响。

单培养结果显示，随着茶多酚浓度增加，植物乳杆菌活菌数先增加后降低，在浓度为2.0 mg/mL 时活菌数最多，而两株致病菌的存活率不断降低，其中金黄色葡萄球菌更为明显。

在共培养体系中（金黄色葡萄球菌/大肠杆菌-植物乳杆菌），随着培养时间延长，植物乳杆菌的生物量不断增加，而致病菌数量和培养基pH 不断降低。

remove organic matter 英文缩写Organic matter, often abbreviated as OM, is a vital component of soil that plays a crucial role in maintaining soil health and fertility. It encompasses all living and once-living materials derived from plants, animals, and microorganisms, including decaying leaves, roots, manure, and other decomposing organic substances. Removing organic matter from soil can have significant implications for soil quality, plant growth, and the overall ecosystem. In this essay, we will explore the importance of organic matter and the potential consequences of its removal.Organic matter serves as a reservoir of essential nutrients for plant growth, including nitrogen, phosphorus, and sulfur. As organic matter decomposes, these nutrients are gradually released into the soil, making them available for uptake by plant roots. Without organic matter, soils would rapidly become depleted of these crucial elements, leading to reduced plant productivity and the need for increased fertilizer applications. Moreover, organic matter improves soil structure by binding soil particles together, creating a crumbly texture that allows for better water infiltration, aeration, and root growth. This improved soil structure also enhances water-holding capacity, reducing the risk of erosion and nutrient leaching.The removal of organic matter can disrupt the delicate balance of soil ecosystems. Soil microorganisms, such as bacteria, fungi, and protozoa, rely on organic matter as a source of energy and nutrients. These microorganisms play vital roles in decomposing organic matter, cycling nutrients, and maintaining soil fertility. Removing organic matter can lead to a decline in microbial populations, potentially impacting nutrient cycling and plant growth. Additionally, organic matter serves as a habitat and food source for soil fauna, including earthworms and arthropods, which contribute to soil aeration, nutrient cycling, and the breakdown of organic matter.Furthermore, organic matter acts as a natural buffer against soil pH fluctuations, helping to maintain a stable soil pH range that is conducive to plant growth and nutrient availability. Its removal can lead to increased soil acidity or alkalinity, potentially limiting plant growth and nutrient uptake. Organic matter also plays a role in carbon sequestration, helping to mitigate the effects of climate change by storing carbon in the soil for extended periods.While certain agricultural practices, such as intensive tillage and monoculture cropping systems, can lead to the depletion of organic matter, there are several strategies that can be implemented to maintain or increase its levels in soil. These include the incorporation of cover crops, crop rotation, and the application of organicamendments like compost or manure. Conservation tillage practices, which minimize soil disturbance, can also help to preserve organic matter by reducing its oxidation and breakdown.In conclusion, organic matter is a vital component of soil that plays numerous roles in supporting plant growth, soil fertility, and ecosystem health. Its removal can have far-reaching consequences, including nutrient depletion, reduced soil structure, decreased microbial activity, and disruptions to nutrient cycling. To maintain healthy and productive soils, it is essential to implement sustainable agricultural practices that prioritize the preservation and replenishment of organic matter. By doing so, we can ensure the long-term viability of our agricultural systems and promote the overall health of our soil ecosystems.。

第19卷　第1期2007年3月 塔　里　木　大　学　学　报Journal of Tari m UniversityVol.19No.1Mar.2007① 文章编号:1009-0568(2007)01-0001-03甘草多糖清除自由基活性的研究杨玲1　汪河滨2　罗锋2(1　塔里木大学文理学院,新疆阿拉尔　843300)(2　新疆生产建设兵团塔里木盆地生物资源保护与利用重点实验室,新疆阿拉尔　843300)摘要　本文利用超声-微波协同萃取法提取甘草多糖,并用分光光度法检测甘草多糖对DPPH自由基、羟自由基(・OH)和超氧阴离子自由基(O2-・)的清除能力。

结果表明,甘草多糖溶液对DPPH自由基、・OH和O2-・均具有较好的清除作用。

关键词　甘草多糖;DPPH自由基,羟自由基(・OH);超氧阴离子自由基(O2-・)中图分类号:R285.5 文献标识码:AStudy on Scaveng i n g Free Rad i ca l Acti v ity w ithPolys acchar i des i n Glycyrrh i za Ura lcn sis F ischYang L ing1　W ang Hebin2　Luo Feng2(1College of A rts and Science,Tari m University,A lar,Xinjiang843300) (2Key Laborat ory of Pr otecti on&U tilizati on of B i ol ogical Res ource in Tari m Basin of Xinjiang Pr oducti on and Constructi on Gr oup s,Tari m University,A lar,Xinjiang843300)Abstract　The study uses ultras onic-m icr owave synergistic extracti on technique t o extract polysaccharides of Glycyrrhiza uralcnsis Fisch and tests the scavenging quality of polysaccharides on DPPH free radical,hydr oxyl free radical(・OH)and super oxide free radi2 cal(O2-・)by s pectr ophot ometry.The result shows that polysaccharides has good scavenging effect on DPPH・,・OH and O2-・. Key words　polysaccharides in Glycyrrhiza uralcnsis Fisch;DPPH free radical;hydr oxyl free radical;super oxide free radical 甘草(Glycyrrhiza u ralcnsis F isch.)系豆科(Legu2 m inosae)甘草属多年生草本植物,是最常用而很有用的中药材[1]。

Plant and Soil241:155–176,2002.©2002Kluwer Academic Publishers.Printed in the Netherlands.155 ReviewStabilization mechanisms of soil organic matter:Implications forC-saturation of soilsJ.Six1,R.T.Conant,E.A.Paul&K.PaustianNatural Resource Ecology Laboratory,Colorado State University,Fort Collins,CO80523,U.S.A.1Corresponding author∗Received3January2001.Accepted in revised form13February2002AbstractThe relationship between soil structure and the ability of soil to stabilize soil organic matter(SOM)is a key element in soil C dynamics that has either been overlooked or treated in a cursory fashion when developing SOM models. The purpose of this paper is to review current knowledge of SOM dynamics within the framework of a newly proposed soil C saturation concept.Initially,we distinguish SOM that is protected against decomposition by various mechanisms from that which is not protected from decomposition.Methods of quantification and characteristics of three SOM pools defined as protected are discussed.Soil organic matter can be:(1)physically stabilized,or protected from decomposition,through microaggregation,or(2)intimate association with silt and clay particles, and(3)can be biochemically stabilized through the formation of recalcitrant SOM compounds.In addition to behavior of each SOM pool,we discuss implications of changes in land management on processes by which SOM compounds undergo protection and release.The characteristics and responses to changes in land use or land management are described for the light fraction(LF)and particulate organic matter(POM).We defined the LF and POM not occluded within microaggregates(53–250µm sized aggregates as unprotected.Our conclusions are illustrated in a new conceptual SOM model that differs from most SOM models in that the model state variables are measurable SOM pools.We suggest that physicochemical characteristics inherent to soils define the maximum protective capacity of these pools,which limits increases in SOM(i.e.C sequestration)with increased organic residue inputs.IntroductionMost current models of SOM dynamics assumefirst-order kinetics for the decomposition of various con-ceptual pools of organic matter(McGill,1996;Paus-tian,1994),which means that equilibrium C stocks are linearly proportional to C inputs(Paustian et al., 1997).These models predict that soil C stocks can, in theory,be increased without limit,provided that C inputs increase without limit,i.e.there are no as-sumptions of soil C saturation.While these models have been largely successful in representing SOM dynamics under current conditions and management practices(e.g.Parton et al.,1987,1994;Paustian et ∗FAX No:+1-970-491-1965.E-mail:johan@ al.,1992;Powlson et al.,1996),usually for soils with low to moderate C levels(e.g.<5%),there is some question of their validity for projecting longer term SOM dynamics under scenarios of ever increasing C inputs(e.g.Donigian et al.,1997).Such scenarios are particularly relevant with the development of new technology designed to promote soil C sequestration through increasing plant C inputs.Native soil C levels reflect the balance of C inputs and C losses under native conditions(i.e.productivity, moisture and temperature regimes),but do not neces-sarily represent an upper limit in soil C stocks.Empir-ical evidence demonstrates that C levels in intensively managed agricultural and pastoral ecosystems can ex-ceed those under native conditions.Phosphorous fer-tilization of Australian pasture soils can increase soil C by150%or more relative to the native condition156(Barrow,1969;Ridley et al.,1990;Russell1960). Soil C levels under long-term grassland(‘near native’) vegetation have also been exceeded in high productiv-ity mid-western no-tillage(NT)systems(Ismail et al., 1994)as well as in sod plots with altered vegetation (Follett et al.,1997).Hence,native soil C levels may not be an appropriate measure of the ultimate C sink capacity of soils.There are several lines of evidence that suggest the existence of a C saturation level based on physiochem-ical processes that stabilize or protect organic com-pounds in soils.While many long-termfield experi-ments exhibit a proportional relationship between C inputs and soil C content across treatments(Larson et al.,1972;Paustian et al.,1997),some experiments in high C soils show little or no increase in soil C content with two to three fold increases in C inputs (Campbell et al.,1991;Paustian et al.,1997;Solberg et al.,1997).Various physical properties(e.g.silt plus clay content and microaggregation)of soil are thought to be involved in the protection of organic materials from decomposer organism.However,these proper-ties and their exerted protection seem to be limited by their characteristics(e.g.surface area),which is con-sistent with a saturation phenomenon(Hassink,1997; Kemper and Koch,1966).A number of soil organic matter models have been developed in the last30years.Most of these mod-els represent the heterogeneity of SOM by defining several pools,typically three tofive,which vary in their intrinsic decay rates and in the factors which control decomposition rates(see reviews by McGill, 1996;Parton,et al.,1994;Paustian,1994).Alternat-ive formulations,whereby specific decomposition rate varies as a function of a continuous SOM quality spec-trum(i.e.instead of discrete pools),have also been developed(e.g.Bosatta and Agren,1996).However, in either case,the representation of the model pools (or quality spectrum)is primarily conceptual in nature. While such models can be successfully validated us-ing measurements of total organic carbon and isotopic ratios of total C(e.g.Jenkinson and Rayner,1977), the individual pools are generally only loosely associ-ated with measurable quantities obtained with existing analytical methods.Consequently,it is not straight-forward to falsify or test the internal dynamics of C transfers between pools and changes in pool sizes of the current SOM models with conceptual pool defin-itions because a direct comparison to measured pool changes is not possible.A closer linkage between theoretical and measur-able pools of SOM can be made by explicitly defining model pools to coincide with measurable quantities or by devising more functional laboratory fractiona-tion procedures or both.The phrases‘modeling the measurable’and‘measuring the modelable’have been coined as representing the two approaches towards a closer reconciliation between theoretical and experi-mental work on SOM(Christensen,1996;Elliott et al.,1996).Various attempts have been made to correlate ana-lytical laboratory fractions with conceptual model pools,with limited success.Motavalli et al.(1994) compared laboratory measurements of C mineraliza-tion with simulations by the Century model(Parton et al.,1994)for several tropical soils.When the active and slow pools in the model were initialized using laboratory determinations of microbial+soluble C for the active pool and light fraction for the slow pool,C mineralization was consistently underestim-ated,although all fractions were highly significantly correlated to C mineralization in a regression ana-lysis.Magid et al.(1996)unsuccessfully attempted to trace14C labeled plant materials using three size-density fractionation methods to define an‘active’pool.Metherell(1992)found that the slow pool in Century was much larger than the particulate organic matter(POM)fraction isolated from a Haplustoll by Cambardella and Elliott(1992).However,Balesdent (1996)found that POM isolated after mild disrup-tion corresponds to the plant structural compartment (RPM)of the Rothamsted carbon model(Jenkinson and Rayner,1997).Acid hydrolysis has been used to estimate Century’s passive C pool(Paul et al.,1997a; Trumbore,1993),but it seems to slightly overestimate the size(Paul et al.,1997a;Trumbore,1993),though not the C turnover rate,of the passive pool(Trumbore, 1993).Nevertheless,Paul et al.(1999)used extended laboratory incubations in combination with acid hy-drolysis to define an active,slow and passive pool of C and were successful in modeling the evolution of CO2in thefield based on these pools.These studies suggest that attempting to measure the modelable has had minimal success to date.There have been a few recent attempts to more closely integrate models and measurements of physi-cochemically defined pools by‘modeling the measur-able’,although Elliott et al.(1996)and Christensen (1996)have presented conceptual models for this ap-proach.Arah(2000)proposed an approach based on analytically defined pools and measurements of13C157Figure1.The protective capacity of soil(which governs the silt-and clay protected C and microaggregate protected C pools),the biochemically stabilized C pool and the unprotected C pool define a maximum C content for soils.The pool size of each fraction is determined by their unique stabilizing mechanisms.and15N stable isotope tracers to derive parameters for a model with measurable pools.The approach con-siders all possible transformations between measured C and N pools and devises a system of equations using observed changes in total C and N and13C and15N for each fraction to solve all model unknowns.Necessary requirements of such an approach are that the analyt-ical fractions are distinct and together account for the total carbon inventory.The objective of this review paper is to summar-ize current knowledge on SOM dynamics and sta-bilization and to synthesize this information into a conceptual SOM model based on physicochemically defined SOM pools.This new model defines a soil C-saturation capacity,or a maximum soil C storage potential,determined by the physicochemical proper-ties of the soil.We propose that the conceptual model developed from this knowledge may form the basis for a simulation model with physicochemically measur-able SOM pools as state variables rather than with the biologically defined pools by Paul et al.(1999).Protected SOM:Stabilization mechanisms, characteristics,and dynamicsThree main mechanisms of SOM stabilization have been proposed:(1)chemical stabilization,(2)phys-ical protection and(3)biochemical stabilization (Christensen,1996;Stevenson,1994).Chemical sta-bilization of SOM is understood to be the result of the chemical or physicochemical binding between SOM and soil minerals(i.e.clay and silt particles).Indeed, many studies have reported a relationship between stabilization of organic C and N in soils and clay or silt plus clay content(Feller and Beare,1997; Hassink,1997;Ladd et al.,1985;Merckx et al., 1985;Sorensen,1972).In addition to the clay con-tent,clay type(i.e.2:1versus1:1versus allophanic clay minerals)influences the stabilization of organic C and N(Feller and Beare,1997;Ladd et al.1992; Sorensen,1972;Torn et al.,1997).Physical protection by aggregates is indicated by the positive influence of aggregation on the accumulation of SOM(e.g.Ed-wards and Bremner,1967;Elliott,1986;Jastrow, 1996;Tisdall and Oades,1982;Six et al.,2000a). Aggregates physically protect SOM by forming phys-ical barriers between microbes and enzymes and their substrates and controlling food web interactions and consequently microbial turnover(Elliott and Coleman, 1988).Biochemical stabilization is understood as the stabilization of SOM due to its own chemical com-position(e.g.recalcitrant compounds such as lignin and polyphenols)and through chemical complexing processes(e.g.condensation reactions)in soil.For our analyses,we divide the protected SOM pool into three pools according to the three stabilization mechanisms described(Figure1).The three SOM pools are the silt-and clay-protected SOM(silt and clay defined as <53µm organomineral complexes),microaggregate-protected SOM(microaggregates defined as53–250µm aggregates),and biochemically protected SOM. Chemical stabilization:Silt-and clay-protected SOM The protection of SOM by silt and clay particles is well established(Feller and Beare,1997;Hassink, 1997;Ladd et al.,1985;Sorensen,1972).Hassink (1997)examined the relationship between SOM frac-tions and soil texture and found a relationship between the silt-and clay-associated C and soil texture,though he did notfind any correlation between texture and amount of C in the sand-sized fraction(i.e.POM C).Based on thesefindings,he defined the capacity158Table1.Regression equations relating silt plus clay proportion to silt and clay associated CSize class a Ecosystem Intercept Slope r20–20µm Cultivated 4.38±0.68b0.26±0.010.41Grassland 2.21±1.940.42±0.080.44Forest−2.51±0.550.63±0.010.550–50µm Cultivated7.18±3.040.2±0.040.54Grassland16.33±4.690.32±0.070.35Forest16.24±6.010.24±0.080.35Size class Clay type Intercept Slope r20–20µm1:1 1.22±0.370.30±0.010.742:1 3.86±0.490.41±0.010.390–50µm1:1 5.5±5.930.26±0.130.382:114.76±2.370.21±0.030.07a Two size classes for silt and clay were reported in the literature.b Value±95%confidence interval.of soil to preserve C by its association with silt and clay particles.Studies investigating the retention of specific microbial products(i.e.amino sugars)cor-roborate the proposition of Hassink(1997)that C associated with primary organomineral complexes arechemically protected and the amount of protection in-creased with an increased silt plus clay proportion of the soil(Chantigny et al.,1997;Guggenberger et al., 1999;Puget et al.,1999;Sorensen,1972).Puget et al.(1999)reported an enrichment of microbial derived carbohydrates in the silt plus clay fraction compared to the sand fraction of no-tilled and conventional tilled soils.However,the amount stabilized by silt and clay differs among microbial products.For example,Gug-genberger et al.(1999)reported a higher increase of glucosamine than muramic acid under no-tillage at sites with a high silt plus clay content.A reexamin-ation of the data presented by Chantigny et al.(1997) leads to the observation that the glucosamine/muramic acid ratio was only higher in perennial systems com-pared to annual systems in a silty clay loam soil and not in a clay loam soil.The silty clay loam soil had a higher silt plus clay content.We expanded the analysis of Hassink(1997)of the physical protection capacity for C associated with primary organomineral complexes(Figure2)across ecosystems(i.e.forest,grassland,and cultivated sys-tems),clay types(i.e.1:1versus2:1),and size ranges for clay and silt(0–20µm and0–50µm;see Ap-Figure 2.The relationship between silt+clay content(%)and silt+clay associated C(g silt+clay C kg−1soil)for grassland,forest and cultivated ecosystems.A differentiation between1:1clay and 2:1clay dominated soils is also made.The relationships indicate a maximum of C associated with silt and clay(i.e.C saturation level for the clay and silt particles),which differs between forest and grassland ecosystems and between clay types.Two size boundaries for silt+clay were used(A)0–20µm and(B)0–50µm. pendices for details).Following the methodology of Hassink(1997)we performed regressions(Figure2 and Table1)between the C content associated with silt and clay particles(g C associated with silt and clay particles kg−1soil;Y axis)and the proportion of silt and clay particles(g silt plus clay g−1soil;X axis).All regressions were significant(P<0.05)and comparison of regression lines revealed that the influ-ence of soil texture on mineral-associated C content differed depending on the size range used for clay and silt particles.Consequently,we did regressions for two different size classes of silt and clay particles(i.e.0–20µm and0–50µm;Figure2and Table1).The intercept for the0–50µm silt and clay particles was significantly higher than for the0–20µm silt and clay particles(Table1).This difference in intercept was159probably a result of the presence of larger sized(20–50µm)silt-sized aggregates in the0–50µm than in the 0–20µm silt and clay particles.These larger silt-sized aggregates have more C per unit material because ad-ditional C binds the primary organomineral complexes into silt-sized aggregates(Tisdall and Oades,1982). However the difference in intercept might also be the result of POM particles of the size20–50µm as-sociated with the0–50µm fraction(Turchenek and Oades,1979).Intercepts for cultivated and forest eco-systems were significantly different for the0–50µm particles,but were only marginally significantly dif-ferent(P<0.06)for the0–20µm particles.Slopes for grassland soils(0–20µm particles)were signi-ficantly different than those for forest and cultivated soils.The differences between grasslands and cultiv-ated lands are likely due to differences in input and disturbance,which causes a release of SOM and con-sequently increased C availability for decomposition. An explanation for the significantly different slopes for grassland and forest soils(Table1)is not imme-diately apparent.Especially that the slope is higher for forest than grassland slopes.This is in contrast to the suggestion that grassland-derived soils have a higher potential of C stabilization than forest-derived because of their higher base saturation(Collins et al.,2000; Kononova,1966).Consequently,this difference in C stabilization by silt and clay particles between forest and grassland systems should be investigated further.In contrast to Hassink(1997),we found signific-antly different relationships for1:1clays versus2:1 clays regressions and for the cultivated versus grass-land regressions(Figure2and Table1)for the0–20µm particles.The effect of clay type was also signific-ant for the0–50µm particles.This lower stabilization of C in1:1clay dominated soils is probably mostly re-lated to the differences between the clay types(see be-low).However,the effect of climate can not be ignored in this comparison because most1:1clay dominated soils were located in(sub)tropical regions.The higher temperature and moisture regimes in(sub)tropical re-gions probably also induce a faster decomposition rate and therefore contributes to the lower stabilization of C by the1:1clays.Nevertheless we believe that the type of clay plays an important role because different types of clay(i.e.1:1and2:1clays)have substantial differences in CEC and specific surface(Greenland, 1965)and should,consequently,have different ca-pacities to adsorb organic materials.In addition,Fe-and Al-oxides are most often found in soils domin-ated by1:1minerals and are strongflocculants.By being strongflocculants,Fe-and Al-oxides can re-duce even further the available surface for adsorption of SOM.We are not certain why soils examined by Hassink(1997)did not follow this reduced capacity to adsorb organic materials;few soils dominated by 1:1clays,however,were included in the data set used by Hassink(1997)and most of them had a low car-bon content.Nevertheless,the difference between the two studies might also be a result of the contrast-ing effect the associated Fe-and Al-oxides can have. The strongflocculating oxides can reduce available surface(see above)but they might also co-flocculate SOM and consequently stabilize it.Therefore,it ap-pears that mechanisms with contrasting effects on SOM stabilization exist and the net effect still needs to be investigated.The different regression lines for grassland and cultivated systems are in accordance with Feller et al.(1997).They also found a signific-ant lower slope for the regression line between the amount of0–2µm particles and the C contained in the0–2µm fraction of cultivated soils compared to non-cultivated soils.The lack of influence of cultiv-ation on the silt and clay associated C observed by Hassink(1997)was probably a result of the low pro-portion of silt and clay and high SOM contents of the soils used.The silt-and clay-associated C formed a small fraction of the total C in his soils.Consequently, sand-associated C accounted for the majority of total soil C.Given this dominance of sand-associated C and its greater sensitivity to cultivation than silt-and clay-associated C(Cambardella and Elliott,1992),in which C is transferred from the sand associated fraction to the silt-and clay-associated fractions during decom-position(Guggenberger et al.,1994),a loss of silt-and clay-associated C upon cultivation is likely to be minimal.In summary,we found,as Hassink(1997)did,a direct relationship between silt plus clay content of soil and the amount of silt-and clay-protected soil C, indicating a saturation level for silt and clay associated C.This relationship was different between different types of land use,different clay types,and for differ-ent determinations of silt plus clay size class.Also, the silt-and clay-associated soil organic matter was reduced by cultivation.Physical protection:Microaggregate-protected SOM The physical protection exerted by macro-and/or mi-croaggregates on POM C is attributed to:(1)the compartmentalization of substrate and microbial bio-160mass(Killham et al.,1993;van Veen and Kuikman, 1990),(2)the reduced diffusion of oxygen into macro-and especially microaggregates(Sexstone et al.,1985) which leads to a reduced activity within the aggregates (Sollins et al.,1996),and(3)the compartmentalization of microbial biomass and microbial grazers(Elliott et al.,1980).The compartmentalization between sub-strate and microbes by macro-and microaggregates is indicated by the highest abundance of microbes on the outer part of the aggregates(Hattori,1988)and a substantial part of SOM being at the center of the aggregates(Elliott and Coleman,1988;Golchin et al., 1994).In addition,Bartlett and Doner(1988)repor-ted a higher loss of amino acids by respiration from the aggregate surfaces than from within aggregates. Priesack and Kisser-Priesack(1993)showed that the rate of glucose utilization decreased with distance into the aggregate.The inaccessibility of substrate for mi-crobes within aggregates is due to pore size exclusion and related to the water-filled porosity(Killham et al., 1993).Many studies have documented a positive influ-ence of aggregation on the accumulation of SOM(An-gers et al.,1997;Besnard et al.,1996;Cambardella and Elliott,1993;Franzluebbers and Arshad,1997; Gale et al.,2000;Golchin et al.,1994,1995;Jastrow, 1996;Monreal and Kodama,1997;Paustian et al., 2000;Puget et al.,1995,1996;Six et al.,1998,1999, 2000a).Cultivation causes a release of C by break-ing up the aggregate structures,thereby increasing availability of C.More specifically,cultivation leads to a loss of C-rich macroaggregates and an increase of C-depleted microaggregates(Elliott,1986;Six et al.,2000a).The inclusion of SOM in aggregates also leads to a qualitative change of SOM.For example, Golchin et al.(1994)reported significant differences in chemical structure between the free and occluded (i.e.within aggregates)light fraction.The occluded light fraction had higher C and N concentrations than the free light fraction and contained more alkyl C(i.e. long chains of C compounds such as fatty acids,lipids, cutin acids,proteins and peptides)and less O-alkyl C(e.g.carbohydrates and polysaccharides).These data suggest that during the transformation of free into intraaggregate light fraction there is a selective decomposition of easily decomposable carbohydrates (i.e.O-alkyl C)and preservation of recalcitrant long-chained C(i.e.alkyl C)(Golchin et al.,1994).Golchin et al.(1995)also found that cultivation decreased the O-alkyl content of the occluded SOM.They sugges-ted that this difference is a result of the continuous disruption of aggregates,which leads to a faster min-eralization of SOM and a preferential loss of readily available O-alkyl C.Hence,the enhanced protection of SOM by aggregates in less disturbed soil results in an accumulation of more labile C than would be maintained in a disturbed soil.Recent studies indicate that the macroaggreg-ate(>250µm)structure exerts a minimal amount of physical protection(Beare et al.,1994;Elliott, 1986;Pulleman and Marinissen,2001),whereas SOM is protected from decomposition in free(i.e.not within macroaggregates)microaggregates(<250µm) (Balesdent et al.,2000;Besnard et al.,1996;Skjem-stad et al.,1996)and in microaggregates within mac-roaggregates(Denef et al.,2001;Six et al.,2000b). Beare et al.(1994)and Elliott(1986)found an increase in C mineralization when they crushed macroaggreg-ates,but the increase in mineralization only accounted for1–2%of the C content of the macroaggregates.In addition,no difference in C mineralization between crushed and uncrushed macroaggregates has been ob-served(Pulleman and Marinissen,2001).In contrast, C mineralization of crushed free microaggregates was three to four times higher than crushed macroaggreg-ates(Bossuyt et al.,2002).Gregorich et al.(1989) observed a substantial higher C mineralization when microaggregates within the soil were disrupted than when lower disruptive energies were used that did not break up microaggregates.Jastrow et al.(1996),us-ing13C natural abundance technique,calculated that the average turnover time of C in free microaggreg-ates was412yr,whereas the average turnover time for macroaggregate associated C was only140yr in the surface10cm.These studies clearly indicate that C stabilization is greater within free microaggregates than within macroaggregates.Further corroborating evidence for the crucial role microaggregates play in C sequestration were reported by Angers et al.(1997), Besnard et al.(1996),Gale et al.(2000)and Six et al.(2000b).Angers et al.(1997)found in afield in-cubation experiment with13C and15N labeled wheat straw that wheat-derived C was predominantly stored and stabilized in free microaggregates.Gale et al. (2000)reported similar C stabilization within free mi-croaggregates in an incubation study with14C-labeled root material.Upon conversion of forest to maize cul-tivation,Besnard et al.(1996)found a preferential accumulation of maize-and forest-derived POM-C in microaggregates compared to other soil fractions. Six et al.(1999)observed a decrease infine intra-macroaggregate-POM(i.e.53–250µm sized POM161(fine iPOM)predominantly stabilized in microaggreg-ates within macroaggregates(Six et al.,2000b))under plough tillage compared to no-till.However,there was no difference in coarse intra-macroaggregate POM (i.e.250–2000µm POM not stabilized by the micro-aggregates within macroaggregates)between tillage systems at three of the four sites studied.They con-cluded that the incorporation and stabilization offine POM-C into microaggregates within macroaggregates and free microaggregates under no-tillage is a dom-inant factor for protection of thefine-sized fraction of POM.Nevertheless,the dynamics of macroaggreg-ates are crucial for the sequestration of C because it influences the formation of microaggregates and the sequestration of C within these microaggregates(Six et al.,2000b).That is,rapid turnover of macroaggreg-ates reduces the formation of microaggregates within macroaggregates and the resulting stabilization of C within these microaggregates(Six et al.,1998,1999, 2000b).Though the incorporation of POM into microag-gregates(versus bonding to clay surfaces;i.e.chem-ical mechanism)seems to be the main process for protection of POM,the clay content and type of soil exert an indirect influence on the protection of POM-C by affecting aggregate dynamics.Franzluebbers and Arshad(1997)suggested that physical protec-tion of POM within aggregates increases with clay content since mineralization of POM-C relative to whole-SOM-C after dispersion and aggregation both increased with increasing clay content(Franzluebbers and Arshad,1996).Different clay types lead to differ-ent mechanisms involved in aggregation(Oades and Waters,1991)and will therefore influence differently the protection of POM through microaggregation. Within the2:1clay minerals,clay minerals with a high CEC and larger specific surface,such as montmoril-lonite and vermiculite,have a higher binding potential than clay minerals with a lower CEC and smaller spe-cific surface,such as illite(Greenland,1965).In con-trast to the2:1minerals,kaolinite and especially Fe-and Al-oxides have a highflocculation capacity due to electrostatic interactions through their positive charges (Dixon,1989;Schofield and Samson,1954).Even though,different mechanisms prevail in soils with dif-ferent clay types,soils seem to have a maximum level of aggregate stability.Kemper and Koch(1966)ob-served that aggregate stability increased to a maximum level with clay content and free Fe-oxides content. Since the physical protection of POM seems to be mostly determined by microaggregation,we hypothes-ize that the maximum physical protection capacity for SOM is determined by the maximum microaggrega-tion,which is in turn determined by clay content,clay type.Biochemical stabilization:Biochemically-protected SOMIn this review,a detailed description of the influ-ence of biochemical stabilization on SOM dynamics will not be given,we refer to an excellent review on this subject by Cadisch and Giller(1997).Nev-ertheless,biochemical stabilization of SOM needs to be considered to define the soil C-saturation level within a certain ecosystem(Figure1).Biochemical stabilization or protection of SOM occurs due to the complex chemical composition of the organic mater-ials.This complex chemical composition can be an inherent property of the plant material(referred to as residue quality)or be attained during decomposition through the condensation and complexation of decom-position residues,rendering them more resistant to subsequent decomposition.Therefore the third pool in our model(Figure1)is a SOM pool that is stabilized by its inherent or acquired biochemical resistance to decomposition.This pool is akin to that referred to as the‘passive’SOM pool(Parton et al.,1987)and its size has been equated to the non-hydrolyzable frac-tion(Leavitt et al.,1996;Paul et al.,1995;Trumbore 1993).Using14C dating,it has been found that,in the surface soil layer,the non-hydrolyzable C is ap-proximately1300years older than total soil C(Paul et al.,1997a,2001).Several studies have found that the non-hydrolyzable fraction in temperate soils includes very old C(Anderson and Paul,1984;Paul et al., 1999;Trumbore,1993;Trumbore et al.,1996)and acid hydrolysis removes proteins,nucleic acids,and polysaccharides(Schnitzer and Khan,1972)which are believed to be more chemically labile than other C compounds,such as aromatic humified compon-ents and wax-derived long chain aliphatics(Paul et al.,1997a).The stabilization of this pool and con-sequent old age is probably predominantly the result of its biochemical composition.However,Balesdent (1996)did notfind any great differences in dynam-ics between the non-hydrolyzable and hydrolyzable C fraction and therefore questioned the relationship between biodegradability and hydrolyzability.Never-theless,we chose the hydrolysis technique to differen-tiate an older and passive C pool,because we think it is the simplest and best available technique to define。

通过做转变层和RAFT技术聚合来制备独立的分子印迹膜并在高效液相色谱中使用摘要独立的分子印迹膜（SS-MIFS）已经通过转变层结构由可逆加成-断裂链转移自由基（RAFT）聚合法来准备。

这个结构，组成和分子印迹的选择性以及质量传递的机理通过电子显微镜，X光照射，傅里叶变换红外光谱仪，比表面积区域分析，热重分析和高效液相色谱进行表征。

分析表明样品具有比表面积高80.5 m2.g−1。

是原始多孔阳极氧化铝基板的几乎9倍以上。

热重分析还表明，样品的热稳定温度高达350 °C。

用高效液相色谱法研究分离能力，揭示了目标分子对可可碱选择性分离的能力。

分离系数为5.37。

关键词：分子印迹膜层状双氢氧化物RAFT聚合化学分离介绍分子印迹膜具有分子印迹和膜技术的特点，现在已成为一种广泛应用于各个领域的技术，如分离，化学传感器，生物受体模型等。

在早期的研究中，分子印迹膜的制备是热或紫外线引发自由基聚合。

这些过程具有简单和容易控制的反应条件，但结果大多有大的颗粒尺寸，不规则形状，从而降低分子印迹效率。

近年来，可控自由基聚合合成超精细、超薄、纳米结构的分子印迹薄膜已成为分子印迹领域的一个重要发展方向。

通过制备方法控制自由基聚合，在分子印迹薄膜样品的活性成分-分子印迹层可以得到稳定性的改善，更均匀和稳定的识别位点，以及较高的分子识别效率。

然而，分子印迹膜的制造方法要么以薄层相邻支撑表面和/或接枝- 从载体材料的反应的选择性启动。

分子印迹层之间的结合的相互作用是弱的范德华力或通过复杂的化学氧化还原或辐射接枝获得的共价键。

此外，这些分子印迹膜的支撑膜是灵活的有机薄膜并不能独立的发挥作用。

因此，无机独立分子印迹膜（SSMIFs）是近年来发展起来的。

例如，杨的团队报道了分子印迹的多孔阳极氧化铝膜的自立建设（PAAO）的内部孔壁直接通过一个浅显的溶胶凝胶过程形成–的印迹层膜。

对多孔薄膜利用刚性基板产生的分子印迹膜具有良好的自支撑结构。

BIOCHAR VOLATILE MATTER CONTENT EFFECTS ON PLANT GROWTH AND NITROGEN TRANSFORMATIONS IN A TROPICALSOILJonathan L. Deenik, A.T. McClellan and G. UeharaDepartment of Tropical Plant and Soil Sciences, University of Hawaii, Honolulu, HI ABSTRACTBiochars made from modern pyrolysis methods have attracted widespread attention as potential soil amendments with agronomic value. A series of greenhouse experiments and laboratory incubations were conducted to assess the effects of biochar volatile matter (VM) content on plant growth, nitrogen (N) transformations, and microbial activities in an acid tropical soil. High VM biochar inhibited plant growth and reduced N uptake with and without the addition of fertilizers. Low VM charcoal supplemented with fertilizers improved plant growth compared with the fertilizer alone. The laboratory experiments showed that high VM biochar increased soil respiration and immobilized considerable quantities of inorganic N. This research shows that biochar with high VM content may not be a suitable soil amendment in the short-term. INTRODUCTIONThe use of biochar as a soil amendment is modeled on the C-rich anthropogenic soils known as “Terra Preta do Indio” (Indian black earth) found in Amazonia and associated with habitation sites of pre-contact Amerindian populations dating as far back as 7,000 cal yr BP (Glaser, 2007). The defining characteristic of Terra Preta soils is the presence of large quantities of charcoal in the soil organic matter to depths of 1 m or greater (Glaser et al., 2000; Sombroek et al., 1993). These soils are remarkable because they have remained fertile and enriched in soil C compared with adjacent forest soils despite centuries of cultivation.Recent efforts to replicate the “Terra Preta” phenomenon using biochars created from modern pyrolysis techniques show that charcoal additions can have an ameliorating effect on highly weathered, infertile tropical soils by increasing CEC and plant nutrient supply, reducing soil acidity and aluminum toxicity, and improving fertilizer efficiency due to reduced nutrient leaching (Glaser at al., 2002; Lehmann et al., 2003). Plant growth response to charcoal amended soils has been variable with both negative and positive results reported in the scientific literature (Glaser at al., 2002). Several studies have reported that plant growth responses are largest when charcoal and fertilizers are combined suggesting a synergistic relationship (Chan et al., 2007; Lehmann et al., 2003; Steiner et al., 2007). Gundale and Deluca (2007) observed that laboratory produced charcoal from ponderosa pine and Douglas-fir had a negative effect on plant growth whereas the same charcoal created from wildfires showed a positive effect on plant growth. The authors speculated that the low temperature charring method used to create the charcoal in the laboratory either created toxic compounds that inhibited plant growth or acted as a source of labile carbon (C) stimulating microbial growth and N immobilization. The objectives of the present research were to determine the effects of charcoal volatile matter content on plant growth and N transformations in a tropical acid soil. We hypothesized that biochar created at low temperatures with high VM would increase microbial activity resulting in a decrease in plant available N due to immobilization.MATERIALS AND METHODSTwo greenhouse bioassays and two laboratory incubations were conducted to test the effects of biochar VM content on plant growth and N transformations. The soil was an infertile, acid Leilehua series (very-fine, ferruginous, isothermic, ustic kanhaplohumults) collected from the 30-80 cm depth at the Waiawa Correctional Facility, Mililani, Oahu Island (N21°26’53”, W157° 57’ 52”). The charcoal feedstock used in our experiments was macadamia nut shells. The charcoal was made using a flash carbonization process developed at the Natural Energy Institute at the University of Hawaii (Antal et al., 2003). Selected chemical properties of the soil and biochars used in the different experiments are presented in Table 1. Total C and N content of the biochars were determined by dry combustion on a LECO CN-2000. Biochar pH was measure in 1:1 slurry of charcoal to deionized water. Base cations were extracted with 1M ammonium acetate at pH 7 and Al+++ was extracted with 1M KCl and measured in solution by inductive coupled plasma spectrophotometer. The effective cation exchange capacity (ECEC) of the biochars and soil was determined by summing the exchangeable cations.Table 1. Selected chemical properties of the Leilehua soil, and the biochars used in the greenhouse and laboratory experiments (LVM = low VM content and HVM = high VM content).VM Ash OC TN pH P K Ca Mg Na Al ECEC%kg-1 cmol c kg-1mgSoilLeilehua 4.28 0.12 4.70 2.22 0.09 0.720.520.29 1.61 3.22 CharcoalLVM6.30 4.18 88.7 0.45 8.1617.2 1.25 3.7 0.31 0.011 22.5MacNutHVM22.5 3.33 85.2 0.45 5.7218.5 0.740.7 0.15 0.032 20.2MacNutIn the first greenhouse bioassay we imposed five treatments consisting of a control (unamended soil), soil+lime, soil+biochar, soil+lime+NPK and soil+biochar+lime+NPK arranged in randomized block design with four replications. The biochar contained 22.5 % VM and was considered a high VM biochar. Biochar was applied to achieve 10% (w/w), lime to achieve 2 T ha-1, N as NH4NO3 at a rate of 200 mg N kg-1, P as Ca(H2PO4)2 to achieve a rate of 750 mg P kg-1, K and Mg were added in solution at a rate equivalent to 200 and 100 kg ha-1 respectively, and the micronutrients Cu, Mn, and Zn were added in solution at a rate of 10 kg ha-1. We used corn (Zea mays, var super sweet #9) as the test crop. Eight corn seeds were planted into each pot and thinned to four plants after emergence. The second greenhouse bioassay consisted of five treatments (unamended soil, soil+lime+NPK, soil + high VM biochar, soil + low VM biochar, soil + low VM biochar + NPK) installed in a complete randomized block design with four replicates. Lime and fertilizers were applied at the same rates as in the first experiment and corn was the test crop. At harvest time, above-ground biomass was cut at the soil surface dried at 70°C for 72 hours, weighed and tissue analyzed for nutrient content according to standard procedures (Hue et al., 2000).We conducted two laboratory studies to evaluate the effect of biochar VM content on net N mineralization rates and on CO2 respiration. Both experiments consisted of three treatments, a control (untreated Leilehua soil) and the Leilehua soil amended with high and low VM macadamia nut biochar applied at the same rate as in the greenhouse experiment. For the Nstudy, the biochar was mixed thoroughly with 50 g (oven dry equivalent) of soil followed by the addition of the appropriate volume of deionized water required to bring the soil to 75% of water holding capacity. The soils were placed in 100 mL beakers, weighed at the outset of the incubation, covered with perforated parafilm, and incubated at constant temperature (28°C) and moisture. Soils were sampled and analyzed for inorganic N, protease activity, and K 2SO 4 extractable organic C and TN after 2, 7, and 14 days. The soluble C fraction of the biochar was determined by shaking 3 g of biochar in 30 mL deionized water for 1 hour and filtering through a 45 μm nylon membrane. For the CO 2 respiration study, we used the alkali adsorption method where 50 g of treated and untreated soils and 50 ml of 0.05 M NaOH were sealed in airtight 1 L mason jars and incubated at 28°C for 14 days (Alef, 1995). The beaker containing the NaOH solution was removed from the mason jar at 48 hour intervals and titrated with 0.05 M HCl following the addition of 0.5 M BaCl 2. Four mason jars with the 0.05 M NaOH solution, but without soil were used as controls.RESULTS AND DISCUSSIONThe high VM biochar used in the first greenhouse bioassay had a significant negative effect on corn growth compared to the control (Fig. 1). Amending the soil with conventional inorganic fertilizers (lime+NPK) produced significant increases in corn growth, but the beneficialcombining charcoal with the fertilizer therewas an approximately 50% decline in corn showed very low N, P and K concentrations in the tissue (data not shown). Tissue N and fertilizers significantly increased tissue N, P, and K concentrations and the accompanying significant rise in dry matter production indicated that the Leilehua soil was severely deficient in N, P, and K. The biochar in combination with fertilizers, however,significantly decreased tissue N, P, and K concentrations compared to the fertilizer control treatment. Our observations were in disagreement with a recent greenhouse experiment reporting that biochar significantly improved N fertilizer use efficiency by radish plants (Chan et al., 2007). We speculated that the relatively high VM content of the biochar used in this experiment may have played a role in inhibiting corn growth. Figure 1. Treatment effects on above ground corn dry matter production in an infertile Leilehua soil amended with high VM biochar and fertilizer (S = soil, S+C = soil + biochar, S+L = soil + lime, S+F+L = soil + NPK + lime, S+C+F = soil + biochar + NPK).The results of the second greenhouse experiment showed that biochar VM content had significant effects on plant growth. High VM biochar significantly reduced shoot dry matter compared with the control whereas low VM biochar had no significant effect on dry mattercharcoal treatment than in the high VMcharcoal treatment. The low VM biocharproduction compared with the fertilizeralone treatment. The high VM biochar reduced N uptake by 50% compared withthe control. On the other hand, the low VM biochar did not reduce N uptake intreatment. Although the low VM biochar with fertilizer treatment did not show ashigh an increase in plant growth nor a significant increase in N uptake compared with the fertilizer treatment as in the results reported by Chan and his group(2007), our results provide evidence that the VM content of the biochar is an important factor affecting its agronomic value as a soil amendment. We suspected that high VM charcoal is a source of labile C for soil microorganisms, and the high C:N ratio of the C source stimulated immobilization of the plant available Nin the soil causing N deficiency in the growing plants. A recent experimentreported similar results showing thatcharcoal produced at low temperature(350°C) had a negative effect on plantgrowth (Gundale and DeLuca, 2007), and the researchers speculated that thedecline in plant growth was caused byphenols in the charcoal, which servedas a high C:N carbon source for soilmicroorganisms.Results from the two incubation VM exerts a strong influence on N mineralization and microbial respiration. The untreated soil showedan initial drop in soil NH 4+-N after twodays from 39.4 to 31.7 mg kg -1 followed by a slow increase to 45.3 and 43.4 mg kg -1 after seven Figure 2. Treatment effects on above ground corn dry matter production in an infertile Leilehua soil amended withhigh and low VM biochar and fertilizer (S = soil, HVM = high VM biochar, LVM = low VM biochar). Figure 3. Biochar effects on soil NH 4+-N in a 14 - day incubation.and fourteen days respectively (Fig. 3). The soil amended with high VM biochar, however, showed a dramatic decline in soil NH 4+-N that persisted throughout the fourteen day incubation. The low VM biochar had a much smaller effect on soil NH 4+-N decreasing it to around 30 mg kg -1. In the CO 2 respiration study, the high VM biochar amendment caused a steep increase in respiration reaching a peak at four days followed by a gradual decline through the 12th day (Fig.4). At day 2 and day 6 the high VMbiochar treatment showed a respiration rate threefold higher than the control, which remained at least twice as high as the control throughout the remainder ofrespiration at day 2 followed by a rapiddecline matching the control values bythe eighth day. The relatively high CO 2 dramatic decline in soil NH 4+-Nconcentration observed in the high VM biochar treatment is strong evidence that biomass was an important factor explaining the observed decline in plant growth and N uptake in the high VMbiochar treatments. The high water extractable C content of the high VM biochar (265 mg C kg -1) compared with the low VM biochar (53 mg kg -1) provided a labile source of C fueling the observed stimulation of microbial activity in the high VM treatment. With the high C:N ratio of the biochar, the microbial biomass was forced to scavenge soil N inducing N deficiency in the growing plants.Figure 4. Biochar effects on CO2 respiration in a 12-day incubation.SUMMARYThis research shows that biochar VM content, or the degree of carbonization, can play a critical role in determining its agronomic value as a soil amendment. Our results provide clear evidence that biochars that are high in VM content (i.e., a typical barbecue charcoal) would not be good soil amendments because they can stimulate microbial activity and immobilize plant available N in the short-term. On the other hand, more fully carbonized biochars with lower VM content containing a smaller labile C component have a smaller effect on soil microbial activity and N immobilization. While our research provides one explanation for why some biochars have a negative effect on plant growth, it still remains unclear why low VM biochars in combination with fertilizer appear to have a beneficial effect on plant growth. Despite our findings elucidating the role of VM content in inhibiting N mineralization, research at the field scale is required to truly assess the agronomic value of biochars as soil amendments.REFERENCESAlef, K. 1995. Soil Respiration, p. 214-216, In K. Alef and P. Nannipieri, eds. Methods inapplied soil microbiology and biochemistry. Academic Press, London.Antal, M.J., K. Mochidzuki, and L.S. Paredes. 2003. Flash carbonization of biomass. Industrial & Engineering Chemistry Research 42:3690-3699.Chan, K.Y., L. Van Zwieten, I. Meszaros, A. Downie, and S. Joseph. 2007. 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ACKNOWLEDGEMENTSWe thank Dr. Michael Antal for providing biochar samples along with proximate analysis data and Yudai Tsumiyoshi and Jocelyn Liu for assistance with laboratory analysis. Funding for this research came in part from USDA HATCH project 863H.。