当前位置：文档库 › Impact of biochar amendments on the quality of a typical Midwestern agricultural soil

Impact of biochar amendments on the quality of a typical Midwestern agricultural soil

David https://www.wendangku.net/doc/094841593.html,ird a ,?,Pierce Fleming a ,Dedrick D.Davis b ,Robert Horton b ,Baiqun Wang c ,Douglas L.Karlen a

USDA,ARS,National Laboratory for Agriculture and the Environment,2110University Blvd.,Ames IA 50011,United States b

Department of Agronomy,Iowa State University,Ames IA 50011,United States c

State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest A&F University,Chinese Academy of Sciences and Ministry of Water Resources,Yangling 712100,Shaanxi,China

a b s t r a c t

a r t i c l e i n f o Article history:

Received 19November 2009

Received in revised form 13May 2010Accepted 24May 2010

Available online 26June 2010Keywords:Biochar Charcoal Black carbon Soil quality Manure

Biochar,a co-product of thermochemical conversion of lignocellulosic materials into advanced biofuels,may be used as a soil amendment to enhance the sustainability of biomass harvesting.We investigated the impact of biochar amendments (0,5,10,and 20g-biochar kg ?1soil)on the quality of a Clarion soil (Mesic Typic Hapludolls),collected (0–15cm)in Boone County,Iowa.Repacked soil columns were incubated for 500days at 25°C and 80%relative humidity.On week 12,5g of dried and ground swine manure was incorporated into the upper 3cm of soil for half of the columns.Once each week,all columns were leached with 200mL of 0.001M CaCl 2.Soil bulk density increased with time for all columns and was signi ?cantly lower for biochar amended soils relative to the un-amended soils.The biochar amended soils retained more water at gravity drained equilibrium (up to 15%),had greater water retention at ?1and ?5bars soil water matric potential,(13and 10%greater,respectively),larger speci ?c surface areas (up to 18%),higher cation exchange capacities (up to 20%),and pH values (up to 1pH unit)relative to the un-amended controls.No effect of biochar on saturated hydraulic conductivity was detected.The biochar amendments signi ?cantly increased total N (up to 7%),organic C (up to 69%),and Mehlich III extractable P,K,Mg and Ca but had no effect on Mehlich III extractable S,Cu,and Zn.The results indicate that biochar amendments have the potential to substantially improve the quality and fertility status of Midwestern agricultural soils.

Published by Elsevier B.V.

1.Introduction

The emerging cellulosic bioenergy industry has been promoted as a means of simultaneously improving energy security,improving weak rural economies,and helping to mitigate the threat of global climate change.Concerns,however,have been raised that the harvesting of crop residues for the production of bioenergy could have adverse impacts on soil and environmental quality (Lal,2004;Wilhelm et al.,2004;Lal and Pimentel,2007).The harvesting of crop residue removes substantial amounts of plant nutrients from soil agro-ecosystems.Unless these nutrients are replaced by the addition of synthetic fertilizers,manure,or other soil amendments the productivity of the soil will decline.Even if synthetic fertilizers are added to replace the removed nutrients,the sustained removal of crop residues without compensating organic amendments will cause a decline in levels of soil organic matter,which will lead to degradation of soil structure,a decline in cation exchange capacity,a decline in the

capacity of soils to hold nutrients and water,and ultimately a decline in soil productivity (Wilhelm et al.,1986).

The loss of soil organic matter also indicates the loss of soil organic C to the atmosphere as CO 2,and hence the necessity of discounting any C offset credits accrued from biofuels displacing fossil fuels.Furthermore,the removal of above ground residue leaves the soil surface vulnerable to raindrop impact,which increases surface crusting,restricts in ?ltra-tion of water,and increases surface runoff and erosion (Blanco-Canqui and Lal,2009).Runoff,erosion and the leaching of nutrients not only degrade soil quality but also adversely impact the quality of water in streams and reservoirs.Thus the emerging cellulosic bioenergy industry will not be sustainable unless new agronomic systems are also deployed that enhance the amount of C that is retained by the soils from which biomass feedstock is harvested.

Application of biochar,a co-product of the pyrolysis platform for transforming lignocelluloses biomass into liquid energy products,to the soils from which biomass was harvested has been proposed as a key component of a potentially sustainable integrated agronomic-biomass –bioenergy production system (Fowles 2007;Lehmann 2007;Laird 2008).During pyrolysis most of the Ca,Mg,K,P,and plant micronutrients,and about half of the N and S in the biomass feedstock are partitioned into the biochar fraction.Thus using the biochar as a soil

Geoderma 158(2010)443–449

?Corresponding author.Tel.:+15152941581.

E-mail address:https://www.wendangku.net/doc/094841593.html,ird@https://www.wendangku.net/doc/094841593.html, (D.A.

Laird).0016-7061/$–see front matter.Published by Elsevier B.V.doi:

10.1016/j.geoderma.2010.05.013

Contents lists available at ScienceDirect

Geoderma

j ou r n a l h o m e p a ge :ww w.e l s ev i e r.c o m/l o c a te /g e o d e rm a

amendment returns most of those nutrients to the soils from which they came.Biochar also increases the capacity of soils to adsorb plant nutrients(Liang et al.,2006;Cheng et al.,2008)thereby reducing leaching losses of nutrients.Biochar has been shown to decrease soil bulk density,and increase cation exchange capacity,nutrient cycling, and the ability of soils to retain plant available water.Thus the use of biochar as a soil amendment is anticipated to increase both nutrient and water use ef?ciency and thereby crop productivity(Glaser et al.,2001; Liang et al.,2006).Indeed several reports indicate that soil biochar applications increase crop yields(Iswaran et al.,1980;Kishimoto and Sugiura,1985;Marjenah,1994;Yamato et al.,2006).

The C content of biochar varies from b1to N80%,depending on the nature of the feedstock and the thermal–chemical process employed (Antal and Grnli,2003;Spokas and Reicosky,2009).In general,the C in biochar is very stable in soil environments(Schmidt et al.,1999;Glaser et al.,2002;Kuzyakov et al.,2009;and Lehmann et al.,2009).Radio C dates of naturally occurring wild?re chars in soils are often measured in1000s y.b.p.(Skjemstad et al.,1998;Pessenda et al.,2001;Swift, 2001;Preston and Schmidt,2006).By contrast,the half-life of C in plant and animal residues if returned directly to the soil is measured in weeks or months.Thus the transformation of biomass C into stable forms of biochar coupled with soil application of the biochar is a system that effectively removes CO2from the atmosphere through photosynthesis and sequesters the C in soils for millennia.Further-more,there are several reports indicating that soil biochar applications reduce emissions of N2O and CH4from soils either by preventing the formation of these potent greenhouse gasses or by enhancing their oxidation after the gasses have formed(Yanai et al.,2007;Spokas and Reicosky,2009).

A key advantage of soil biochar applications is that C offset credits can be easily and accurately quanti?ed based on the amount of biochar C applied to the soil and the stability of the biochar C.Soil biochar applications may also qualify for less easily quanti?ed C offset credits based on reductions in N2O and CH4emissions,increase crop productivity and/or reductions in agricultural inputs due to increased fertilizer and water use ef?ciency(Laird et al.,2009).Because of C offset credits accrued through soil biochar applications,bioenergy produced through an integrated biomass–bioenergy–biochar platform,may be viewed as C-negative energy and there is a potential for such a system to result in agrading soil quality rather than degrading soil quality.

Much of the previous work on the impact of biochar on soil quality has been conducted in the tropics.The highly weathered Oxisols and Ultisols of the tropics intrinsically have low nutrient retention capacity due to a dominance of Fe-and Al-oxides and1:1phyllosilicates in the clay fraction.By contrast,Midwestern Mollisols are typically domi-nated by2:1phyllosilicates clays,have higher levels of soil organic matter,and higher nutrient and water holding capacities.Here we test the hypothesis that soil biochar amendments will enhance the quality of a typical Midwestern Mollisol by quantifying the impact of biochar and manure amendments on various soil quality indicators using a soil column leaching/incubation study.A companion paper(Laird et al., 2010)reports the leaching of nutrients from the same soil columns.

2.Materials and methods

2.1.Soil and charcoal

Surface(0to15cm)soil(Clarion,?ne-loamy,mixed,superactive, Mesic Typic Hapludolls)was collected from a fallow strip between ?eld plots on the Iowa State University Agronomy and Agricultural Engineering Research Farm in Boone County Iowa.The soil was stored at?eld moisture content in plastic buckets with tight closing lids until it could be used within one month of collection.

Lump charcoal N1cm was obtained from a commercial producer who uses mixed hardwood[primarily oak(Quercus spp.)and hickory (Carya spp.)]and slow pyrolysis(traditional kilns)to produce high C charcoal that is used primarily in the steel industry.The lump charcoal was ground in a hammer-mill and the b0.5mm fraction(here after referred to as biochar)was separated by dry sieving.Basic properties of the biochar(moisture,volatiles,?xed carbon and ash content)were determined by proximate analysis(ASTM standard1762-84(2007)). Total C and N in the biochar and freeze-dried swine manure were determined by dry combustion using a Carlo Erba NA1500NSC elemental analyzer(Haake Buchler Instruments,Paterson,NJ).Elemen-tal composition of biochar and manure was determined by ashing the samples at700°C,digesting the ash in aqua regia,and analyzing the elemental composition of the digest by inductively coupled plasma-atomic emission spectroscopy.Calcium carbonate equivalent was determined by gradually titrating a biochar suspension to neutrality with0.5M HCl over a period of39days.The long period was required because the slurry pH would drop immediately when an aliquot of acid was added but then slowly increase over the next24h.

2.2.Preparation of soil columns

Batches(15kg)of?eld moist soil were tumbled in a rotary cement mixer for20min.During the tumbling treatment a predetermined amount of the biochar was slowly added to the soil to bring the?nal biochar content to0,5,10,or20g kg?1of oven dry soil.The tumbling treatments produced roughly spherical soil aggregates～1cm diameter.

Soil columns(7.7cm id by25cm length=1164cm3volume)were constructed of PVC tubing and?tted with PVC end caps on the bottoms.A hole was drilled through the end caps and drain tubes (3mm i.d.)were attached to the bottom of each column.A small amount of?berglass was inserted into the drain opening at the base of the columns and then100g of coarse sand(2–5mm)was placed in the bottom of each column.The sand?lled the concave portion of the end cap which protruded below the base of the PVC column.The soil columns were packed with1kg(oven dry weight equivalent)of moist soil by tamping the columns as the soil was added.All columns were packed to an initial bulk density of1.1g cm?3.

2.3.Soil column incubation and leaching

The columns were incubated in a constant temperature room (25°C and80%relative humidity)for the duration of the study.On week12of the incubation5g of dried and ground swine manure was added to half of the columns.The manure was incorporated into the top3cm of the soil in the columns using a laboratory spatula.Control columns not receiving manure were also tilled in a similar manner. Once each week during the incubations,all columns were leached with200mL of0.001M CaCl2.The leachate was introduced on the top of each column using a slow(～1h)dripping technique with the aid of a syringe barrel and?ow restricting needle mounted above the middle of each column.A25mm?berglass?lter paper was placed in the middle of each column to help disperse water drops as they impacted on the upper surface of the soil in the columns.

2.4.Analysis of soil column properties

Soil bulk density was determined periodically during the incubation by measuring the distance from the soil surface to the top of the column. From this measurement we determined the volume of headspace above the soil in the column and by difference the soil volume.Soil bulk density was then determined by dividing the known mass of soil added to the columns by the soil volume.This method of determining bulk density yields an average bulk density for the entire column and assumes no change in soil mass through the incubation.

Gravity drained equilibrium water content and saturated hydraulic conductivity were determined at the end of the leaching-incubation experiment.Drain tubes on the bottom of each column were connected to a common water(0.001M CaCl2)source,and the water content of the

444 https://www.wendangku.net/doc/094841593.html,ird et al./Geoderma158(2010)443–449

columns was slowly increased to saturation by raising the water source until the head height was slightly above the upper surface of the soil in the columns.Saturated hydraulic conductivity was then measured by the constant head method(Klute,1965).Water retention at gravity drained equilibrium was determined by allowing the saturated columns to freely drain for48h and then measuring the gross weight of each column.The mass of water retained by the soil was determined by subtracting the PVC column,sand,and oven dry soil weights from the gross column weights.

2.5.Analysis of soil properties

After the saturated hydraulic conductivity and gravity drained equilibrium water content determinations were completed,the intact soil cores were removed from the columns with the aid of high pressure Ar gas line attached to the drain holes in the bottom of the columns.The soil cores where then sectioned to separate soil samples for the0–3cm,3–6cm,and6cm–bottom depth increments.Soil samples were dried on the laboratory bench for two weeks and then stored in sealed plastic bags until analyzed.

For each soil sample,total C and N were determined by high temperature combustion using a Carlo Erba NA1500NSC elemental analyzer(Haake Buchler Instruments,Paterson,NJ).Effective cation exchange capacity was determined using the method of Sumner and Miller(1996).Plant available nutrients were extracted using the Mehlich3method and analyzed by inductively coupled plasma-atomic emission spectroscopy(Mehlich,1984).Soil pH was determined using the method described by Thomas(1996).Speci?c surface area was determined using the EGME method(Carter et al.,1986),and water retention was measured at?33,?100,?500,and?1500kPa soil water matric potential using a pressure plate apparatus(Dane and Hopmans,2002).Water retention measurements were determined on soil samples collected from the6cm-bottom depth increment for the no-manure control columns only.

2.6.Statistical analysis

The overall experimental design included4biochar rates,2 manure treatments,and6replications(48columns)and soil samples collected from three depth increments for each column.The treatments were randomly assigned to columns arranged on two tables each holding24columns within the same constant tempera-ture room.Blocking by table was not signi?cant and thus a completely randomized design was used for all statistical analyses.A three-way analysis of variance was used to determine signi?cance of the overall model,biochar,manure,depth and interaction terms for total C,N, ECEC,pH,and Mehlich3extractable nutrients.A two-way analysis of variance was used for gravity drained equilibrium water content and bulk density,which were measured on whole columns and therefore did not include a depth variable.A one-way analysis of variance was used to evaluate biochar treatment effects for moisture retention and speci?c surface as these were measured only for the0–6cm depth increment of the control(no-manure)columns.Tukey's Studentized Range test(alpha0.05)was used to distinguish differences among treatment means.All statistical analyses were conducted using SAS 9.1for Windows.

3.Results and discussion

The biochar used in this study contained71.5%total C and0.72% total N by mass,and63.8%?xed C,19.7%volatiles,13.9%ash and2.6% moisture by proximate analysis.The pH of the biochar was7.6when ?rst placed in deionized water but increased to8.2after7days.The swine manure was41.3%C and3.51%N on a dry weight basis. Amounts of N,P,Ca,K,Mg,Si,Na,Cu,Mn,and Zn added to the columns by the various biochar and manure treatments are given in Table1of the companion manuscript(Laird et al.,2010).

Total soil organic C is one of several key indicators of soil quality (Andrews et al.,2004).Here the addition of biochar to the soil without manure signi?cantly increased the total C content measured after the 500-day incubation by17.6,37.6and68.8%,respectively,for the5,10, and20g kg?1biochar treatments relative to the0g kg?1biochar controls(Tables1and2).Based on the known C content of the biochar and mass balance analysis,there was no detectable loss of the biochar C during the500-day incubation.By contrast,the manure treatments did not have a signi?cant effect on the total C content of the whole column soils.The manure treatments,however,were only incorpo-rated to a depth of3cm,and analysis of the C content for the0–3cm depth increment revealed a small increase(average6.4%)in C content for the manure treated columns relative to the no-manure controls. Based on mass balance analysis of C for the0–3cm depth increment only,less than20%of the manure C was recovered at the end of the 500-day incubation.The results demonstrate a critical difference in the relative stability of C in biochar,which is highly stable in soil environments,and the C in manure or other biological sources,which is subject to relatively rapid mineralization in soil environments.

Total N content of the soil in the no-manure control columns signi?cantly increased by0.6,4.7and6.9%respectively for the5,10,and 20g kg?1biochar treatments(Tables1and2).Total N in the soil of the manure treated columns averaged only2%higher than the total N in the soil of the no-manure control columns,and this difference was not statistically signi?cant.More N was added to the columns with the manure(195mg N per column)than with the biochar(144mg N for the20g kg?1biochar treatment).Thus the results suggest that N in the biochar is present in a more stable form than the N in the manure. During pyrolysis a signi?cant fraction of the N in proteins and peptides is transformed into N heteroaromatic compounds(Knicker et al.,2008), which may be resistant to microbial degradation.

The relatively large standard deviations associated with C and N determinations of soils by thermal combustion obscure any biochar by manure interactions that may in?uence the recovery of manure C or N. However,because C and N were determined simultaneously for the same sample,the C:N ratios have much greater precision than either C or N alone.This is so because errors associated with measuring the sample weights,moisture content,and certain instrument errors cancel out when C:N ratios are calculated.Our analysis of C:N ratios for the whole column soils still failed to detect a manure by biochar interaction (Table1),however our analysis of C:N ratios for the0–3cm depth increment revealed a signi?cant manure by biochar interaction (P N F=0.0037).Furthermore,our analysis showed that the amount of leachate N attributed to the manure from these columns during the?rst 45weeks of the incubation decreased signi?cantly from60to40%with increasing biochar additions(Laird et al.,2010).Combined,these results suggest that biochar helped stabilize some of the N that was added with the manure.

The capacity of soils to retain plant available water is another key indicator of soil quality(Andrews et al.,2004).Here we measured

Table1

Analysis of variance showing signi?cance(P N F)for the effect of biochar,manure and depth on soil quality indicators measured after the500-day incubation of soil columns with weekly leaching.Mean values for these soil quality indicators are given in Table2.

Source DF C N C:N ECEC pH

Model23b0.0001b0.0001b0.0001b0.0001b0.0001 Biochar3b0.0001b0.0001b0.0001b0.0001b0.0001 Depth2b0.0001b0.00010.0012b0.0001b0.0001 Manure10.0026b0.0001b0.00010.12b0.0001 Biochar?depth60.250.820.750.0630.33 Biochar?manure30.820.990.540.00020.069 Depth?manure20.0003b0.0001b0.00010.200.0001 Biochar?depth?manure60.160.330.120.490.53

445

https://www.wendangku.net/doc/094841593.html,ird et al./Geoderma158(2010)443–449

moisture retention in two ways.First,the amount of water retained by soil in the columns at gravity drained equilibrium was respectively10, 12,and15%greater for the5,10,and20g kg?1biochar treatments than the water retained by the0g kg?1biochar control columns(Fig.1).By contrast,the manure treatments did not have a signi?cant effect on water retention at gravity drained equilibrium.Second,soil samples excavated from the6cm-bottom depth increment of columns not receiving manure retained13%and10%more water at?1and?5bars of soil water matric potential for the20g kg?1biochar treatments relative to the0g kg?1biochar treatments(Fig.2).No effect of biochar on moisture retention at?0.33and?15bar soil water matric potential was detected.No signi?cant effects of biochar or manure were detected on saturated hydraulic conductivity;hence the data are not reported here.The ability of biochar to increase the moisture retention capacity of soils has the potential to increase crop yields for crops exposed to water stress during critical periods of the growing season.

Farmers periodically invest in agricultural lime applications to counter the acidifying effects of ammoniacal fertilizers.Pyrolysis partitions acids into the bio-oil fraction and bases into the biochar,as such some forms of biochar are liming agents.The biochar used in this study had a pH of8.2in deionized water.After the500-day incubation, the soil pH signi?cantly increased by almost1pH unit for the20g kg?1 biochar treatments(Tables1and2).The calcium carbonate equivalent (CCE)value for the biochar,determine by acid titration was8.8, indicating that the hardwood biochar used in this study was a relatively weak liming agent.Biochars produced from pyrolysis of maize and wheat stover will likely have higher CCE values due to higher ash content.

Bulk density is an important indicator of the physical condition of the soil.The soils in the columns were initially packed to a bulk density of 1.1g cm?3.During the500-day incubation/leaching experiment the soil consolidated due to the effects of gravity and leaching water application impacts.For all6dates during the incubations on which bulk

Table2

Mean values(n=6)for soil quality indicators measured after the500-day incubation of soil columns with weekly leaching.Biochar treatments,C0,C5,C10,and C20include amendment of0,5,10,and20g-biochar kg?1,respectively.The“M”in the treatment name indicates incorporation of5g of dried swine manure into the top3cm of soil on week12 of the incubation.Minimum signi?cant(alpha0.05)differences between any two means are based on the Tukey Studentized Range test.Analysis of variance for these data is presented in Table1.

Soil property and depth Biochar treatments without manure Biochar treatments with manure Tukey minimum

signi?cant difference C0C5C10C20C0M C5M C10M C20M

C(%)

0–3cm 1.99 2.38 2.73 3.51 2.15 2.52 2.92 3.630.224 3–6cm 2.00 2.32 2.67 3.44 2.01 2.38 2.78 3.35

6cm–bottom 2.00 2.35 2.79 3.31 1.95 2.34 2.71 3.39

N(%)

0–3cm0.1680.1700.1780.1800.1930.1930.2000.2080.017 3–6cm0.1670.1680.1700.1800.1770.1750.1820.180

6cm–bottom0.1680.1700.1780.1780.1630.1700.1720.178

C:N

0–3cm11.914.015.319.511.113.114.617.4 1.30 3–6cm12.013.815.719.111.413.615.318.6

6cm–bottom11.913.815.718.612.013.815.819.0

ECEC(cmol/kg)

0–3cm17.119.820.720.817.517.819.221.6 2.44 3–6cm16.319.019.819.616.317.418.820.2

6cm–bottom17.618.018.319.417.117.518.321.0

0–3cm 6.40 6.42 6.907.13 5.95 6.07 6.45 6.750.476 3–6cm 6.33 6.55 6.887.23 6.03 6.42 6.827.08

6cm–bottom 6.60 6.577.037.25 6.32 6.857.05

7.17

Fig. 1.Water content at gravity drained equilibrium in the soil columns(water remaining after48hr of free drainage).Error bars show standard deviations and treatment means with different letters are signi?cantly different(alpha0.05)by the Tukey Studentized Range

test.Fig.2.Water retention for soil excavated from the6cm-bottom depth increment of the control(no manure)columns.Error bars show standard deviations and treatment means with different letters are signi?cantly different(alpha0.05)by the Tukey Studentized Range test.

446 https://www.wendangku.net/doc/094841593.html,ird et al./Geoderma158(2010)443–449

density was measured,the biochar treated columns had signi?cantly lower bulk densities than the no-biochar controls(Fig.3).The manure additions did not have a signi?cant effect on bulk density.The magnitude of the biochar effect on bulk density was larger than can be explained by simple dilution of the soil with the low bulk density biochar,furthermore the effect of5g kg?1biochar treatments was nearly as large as the effect of the20g kg?1biochar treatments.The results con?rm that biochar is an effective soil conditioner(Kishimoto and Sugiura,1985).

Cation exchange capacity and speci?c surface area are indirect measures of the capacity of soils to retain water,nutrients,and various contaminants.Here speci?c surface area was measured by the EGME adsorption method for the6cm–bottom depth increment of the no-manure control columns only.The speci?c surface area increased from 130to153m2g?1as the biochar concentration increased from0to 20g kg?1(Fig.4).This difference indicates that the effective surface area of the biochar after the500-day incubation in the soil was 1150m2g?1.The biochar treatments signi?cantly increased ECEC by 4to30%relative to the controls(Tables1and2).Based on these results we estimate that the effective ECEC of the biochar used in this study was187cmol kg?1.Here“effective surface area”and“effective

ECEC”are de?ned as the surface area or ECEC of biochar treated soil minus the surface area or ECEC of the control soil divided by the relative mass of biochar added to the soil.As noted by Cheng et al. (2008)fresh biochar may have relatively low CEC values but the CEC increases on incubation in soil environments due to oxidation of the biochar surfaces and/or adsorption of organic acids by the biochar. Clearly,the500-day incubations were suf?cient for signi?cant CEC to develop on the biochar.We observed a small but signi?cant decrease in ECEC with soil depth for most treatments.The cause of this decrease in ECEC with depth cannot be determined from the available data; however we speculate that the effect is related to differences in the extent of surface oxidation.Although the columns were freely drained (at all times except during measurement of saturated hydraulic conductivity),differences in gravimetric potential with depth and the matrix potential difference between the soil and the coarse sand in the bottom of the columns probably cause relatively higher water contents and lower pO2values in the lower half of the columns.These differences could affect both the rate and the extent of surface oxidation on biochar particles.The manure additions did not have a signi?cant effect on ECEC,however there was a signi?cant biochar by manure interaction(Table1)for which we have no explanation.

Plant nutrients were present in the soil,added with the biochar and added with the manure.Leaching losses of plant nutrients from these columns were discussed by Laird et al.(2010).Here,we use the Mehlich3extraction to assess the levels of bioavailable nutrients that remained in the soils at the end of the500-day leaching/incubation experiment.We observed signi?cant increases in Mehlich3extractable P,K,Ca,and Mn with the amount of biochar added(Tables3and4).The biochar treatments had no signi?cant effect on Mehlich3extractable Mg,Cu,and Zn.The increases in Mehlich3extractable K,Ca,and Mn with increasing levels of biochar are most likely due to the presence of these nutrients in the biochar itself.Phosphorous on the other hand was present in relatively low concentrations in the biochar and relatively high concentrations in the manure,and the increase in Mehlich3extractable P with increasing biochar additions was primarily associated with the0–3cm

depth

Fig.3.Average bulk density for soil in the columns determined periodically during the incubation.Biochar treatments,C0,C5,C10,and C20include amendment of0,5,10, and20g-biochar kg?1,respectively.The"M"in the treatment name indicates incorporation of5g of dried swine manure into the top3cm of soil on week12of the incubation. Error bars show standard deviations and treatment means with different letters are signi?cantly different(alpha0.05)by the Tukey Studentized Range

test.

Fig.4.Speci?c surface area determine by the EGME method for soil samples excavated

from the6cm-bottom depth increment of the no-manure control columns.Biochar

treatments,C0,C5,C10,and C20include amendment of0,5,10,and20g-biochar kg?1,

respectively.Error bars show standard deviations and treatment means with different

letters are signi?cantly different(alpha0.05)by the Tukey Studentized Range test.

447

https://www.wendangku.net/doc/094841593.html,ird et al./Geoderma158(2010)443–449

increment of the manure amended soils(Table4).For Mehlich3 extractable P,the biochar by manure interaction was not statistically signi?cant(P N F0.28),however the biochar by manure by depth interaction was highly signi?cant(P N F b0.0001).Furthermore,the total amount of P leached from the manure amended columns during weeks0–45decreased with increasing levels of biochar(33.6,19.8, 15.2,and10.1mg-P per column for the C0M,C5M,C10M,and C20M treatments respectively;Laird et al.,2010).These results indicate that

Table3

Analysis of variance showing signi?cance(P N F)of biochar,manure,and depth on Mehlich3extractable nutrients(mg kg?1)measured after the500-day incubation of soil columns with weekly leachings.Mean values for these analyses are given in Table4.

Source DF B Ca Cu Fe K Mg Mn P S Zn

Model230.037b0.0001b0.00010.0023b0.0001b0.00010.038b0.0001b0.0001b0.0001 Biochar30.026b0.00010.460.020b0.00010.14b0.0001b0.00010.120.50 Manure10.740.49b0.00010.67b0.0001b0.00010.038b0.0001b0.0001b0.0001 Depth20.11b0.0001b0.00010.0067b0.0001b0.00010.22b0.0001b0.0001b0.0001 Biochar?manure30.00080.320.300.400.110.0550.610.280.550.63 Manure?depth20.960.19b0.00010.00020.590.150.91b0.0001b0.0001b0.0001 Biochar?depth60.840.370.980.570.780.190.950.00240.800.94 Biochar?manure?depth60.670.140.990.560.380.190.68b0.00010.570.93

Table4

Mean values(n=6)for Mehlich3extractable nutrients measured after the500-day incubation of soil columns with weekly leaching.Biochar treatments,C0,C5,C10,and C20 include amendment of0,5,10,and20g-biochar kg?1,respectively.The“M”in the treatment name indicates incorporation of5g of dried swine manure into the top3cm of soil on week12of the incubation.Minimum signi?cant(alpha0.05)differences between any two means are based on the Tukey Studentized Range test.Analysis of variance for these data is given in Table3.

Element and depth Biochar treatments without manure Biochar treatments with manure Tukey minimum

signi?cant difference C0C5C10C20C0M C5M C10M C20M

0–3cm201422172414142013 3–6cm1613191518141415

6cm–bottom1913221417181219

0–3cm35133796379141203373362540114393522 3–6cm33223610377042613216355038114105

6cm–bottom32953146347839673287347436073954

0–3cm 2.8 2.7 2.9313.712.312.612.6 2.9 3–6cm 2.6 2.6 2.8 3.1 6.6 5.1 5.7 5.5

6cm–bottom 2.7 2.83 2.83 2.8 2.8 2.8

0–3cm226195227187266241249226120 3–6cm224185202200238224230229

6cm–bottom313300303198236225223221

0–3cm13714014115215415416817831 3–6cm155149168182175190196204

6cm–bottom180170192209193209223222

0–3cm13112912313316414316919553 3–6cm219195218211225242254259

6cm–bottom304274283280301313307298

0–3cm14615315416114715416616730 3–6cm149146160166151158161165

6cm–bottom153150159168160167163167

0–3cm88949510425426529934944 3–6cm10099111120187199215212

6cm–bottom10694111127149147141139

0–3cm14101110171517166 3–6cm101111913101111

6cm–bottom1212121111111111

0–3cm 3.1 3.2 3.4 3.434.933.435.536.67.6 3–6cm 2.9 2.8 3.2 3.214.610.312.811.8

6cm–bottom 2.8 2.6 2.8 3.2 4.2 3.23 3.4

448 https://www.wendangku.net/doc/094841593.html,ird et al./Geoderma158(2010)443–449

the biochar increased retention of the manure P,primarily in the0–3cm depth increment.By contrast,Mehlich3extractable B decreased with increasing levels of biochar(P N F0.026).Extractable S also decreased with increasing levels of biochar,however the effect was not signi?cant(P N F0.11).Both B and S are present as oxyanions in soil environments,and it is plausible that these oxyanions are being tightly bound by the biochar such that they are less extractable by Mehlich3.In soils P is present in both organic and oxyanion forms. Here we observe a small increase in total Mehlich3extractable P with increasing levels of biochar but the increase was less than differences in leaching losses for the manure treated columns.Thus our data suggest that some of the added P may also have been tightly bound by the biochar.

For the Clarion loam,our results demonstrate that biochar additions signi?cantly reduced bulk density increases due to soil compaction,and increased water holding capacity,cation exchange capacity,speci?c surface area,pH,and the retention of P and several other plant nutrients. All of the observed changes in soil quality indicators were positive with the exception of a slight decrease in Mehlich3extractable B.Manure amendments by contrast had no effect on water retention at gravity drained equilibrium or ECEC,and had relatively small effects on total C, N and C:N ratios.The impact of the manure treatments on Mehlich3 extractable nutrients was generally signi?cant as relatively large amounts of nutrients were added with the manure.In general,the impact of the biochar amendments on soil quality was much more evident after500days than the impact of the manure amendments. Most previous work on the impact of biochar on soil quality has been conducted using tropical and/or degraded soils.By contrast,the Clarion loam is a highly productive temperate region agricultural soil that contains2.0%organic C and is dominated by2:1phyllosilicate clay minerals.Much future research,however,is needed to determine whether crop yields respond to the observed improvement in soil quality indicators for the Clarion loam and to determine the impacts of different types of biochar and soil by biochar interactions for temperate region soils.

References

Andrews,S.S.,Karlen,D.L.,Cambardella,C.A.,2004.The soil management assessment framework:a quantitative soil quality evaluation method.Soil Science Society of America Journal68,1945–1962.

Antal,J.M.,Grnli,M.,2003.The art,science,and technology of charcoal production.

Industrial and Engineering Chemistry Research42,1619–1640.

Blanco-Canqui,H.,Lal,R.,2009.Crop residue removal impacts on soil productivity and environmental quality.Critical Reviews in Plant Sciences28,139–163.

Carter,D.L.,Mortland,M.M.,Kemper,W.D.,1986.Speci?c surface,In:Klute,A.,et al.

(Ed.),Methods of Soil Analysis Part1,Second Edition.:Physical and Mineralogical Methods,9.Soil Science Society of America,Madison,WI,pp.413–423.

Cheng,C.H.,Lehmann,J.,Engelhard,M.H.,2008.Natural oxidation of black carbon in soils:changes in molecular form and surface charge along a climosequence.

Geochimica et Cosmochimica Acta72,1598–1610.

Dane,J.H.,Hopmans,J.W.,2002.Water retention and storage.In:Dane,J.H.,Topp,G.C.

(Eds.),Methods of Soil Analysis.Part.4.SSSA Book Ser.5.Soil Science Society of America,Madison,WI,pp.671–796.

Fowles,M.,2007.Black carbon sequestration as an alternative to bioenergy.Biomass& Bioenergy31,426–432.

Glaser, B.,Haumaier,L.,Guggenberger,G.,Zech,W.,2001.The‘Terra Preta’phenomenon:a model for sustainable agriculture in the humid tropics.Die Naturwissenschaften88,37–41.Glaser,B.,Lehmann,J.,Zech,W.,2002.Ameliorating physical and chemical properties of highly weathered soils in the tropics with charcoal—a review.Biology and Fertility of Soils35,219–230.

Iswaran,V.,Jauhri,K.S.,Sen,A.,1980.Effect of charcoal,coal and peat on the yield of moong,soybean and pea.Soil Biology&Biochemistry12,191–192.

Kishimoto,S.,Sugiura,G.,1985.Charcoal as a soil conditioner.International Achieve Future5,12–23.

Klute,A.,https://www.wendangku.net/doc/094841593.html,boratory measurement of hydraulic conductivity of saturated soil.In: Black,C.A.,et al.(Ed.),Methods of Soil Analysis.Part I.Soil Science Society of America,Madison,WI,pp.210–221.

Knicker,H.,Hilscher,A.,González-Vila,F.J.,Almendros,G.,2008.A new conceptual model for the structural properties of char produced during vegetation?res.

Organic Geochemistry39,935–939.

Kuzyakov,Y.,Subbotina,I.,Chen,H.Q.,Bogomolova,I.,Xu,X.L.,2009.Black carbon decomposition and incorporation into soil microbial biomass estimated by14C labeling.Soil Biology&Biochemistry41,210–219.

Laird,D.A.,2008.The Charcoal Vision:a win–win–win scenario for simultaneously producing bioenergy,permanently sequestering carbon,while improving soil and water quality.Agronomy Journal100,178–181.

Laird,D.A.,Brown,R.C.,Amonette,J.E.,Lehmann,J.,2009.Review of the pyrolysis platform for co-producing bio-oil and biochar.Biofuels Bioproducts and Biore?ning3,547–562. Laird,D.A.,Fleming,P.D.,Wang,B.,Horton,R.,Karlen,D.L.,2010.Biochar impact on nutrient leaching from a midwestern agricultural soil.Geoderma.doi:10.1016/j.

geoderma.2010.05.012.

Lal,R.,2004.Is crop residue a waste?Journal of Soil Water Conservation59,136–139. Lal,R.,Pimentel,D.,2007.Biofuels from crop residues.Soil Tillage Research93,237–238. Lehmann,J.,2007.Bio-energy in the black.Frontiers in Ecology and the Environment5, 381–387.

Lehmann,J.,Czimczik, C.,Laird,D.,Sohi,S.,2009.Stability of biochar in soil.In: Lehmann,J.,Stephen,J.(Eds.),Biochar for Environmental Management.Earthscan, London,pp.193–206.

Liang,B.,Lehmann,J.,Solomon,D.,Kinyangi,J.,Grossman,J.,O'Neill,B.,Skjemstad,J.O., Thies,J.,Luiza,F.J.,Petersen,J.,Neves,E.G.,2006.Black carbon increases cation exchange capacity in soils.Soil Science Society of America Journal70,1719–1730. Marjenah,M.S.,1994.Effect of charcoaled rice husks on the growth of Dipterocarpaceae seedlings in East Kalimantan with special reference to ectomycorrhiza formation.

Journal of Japanese Forestry Society76,462–464.

Mehlich,A.,1984.Mehlich No.3soil test extractant:a modi?cation of Mehlich No.2 https://www.wendangku.net/doc/094841593.html,munications in Soil Science and Plant Analysis15,1409–1416. Pessenda,L.C.R.,Gouveia,S.E.M.,Aravena,R.,2001.Radiocarbon dating of total soil organic matter and humin fraction and its comparison with14C ages of fossil charcoal.Radiocarbon43,595–601.

Preston,C.M.,Schmidt,M.W.I.,2006.Black(pyrogenic)carbon:a synthesis of current knowledge and uncertainties with special consideration of boreal regions.

Biogeosciences3,397–420.

Schmidt,M.W.I.,Skjemstad,J.O.,Gehrt,E.,K?gel-Knabner,I.,1999.Charred organic carbon in German chernozemic soils.European Journal of Soil Science50,351–365. Skjemstad,J.O.,Janik,L.J.,Taylor,J.A.,1998.Non-living soil organic matter:what do we know about it?Australian Journal of Experimental Agriculture38,667–680. Spokas,K.A.,Reicosky, D.C.,2009.Impacts of sixteen different biochars on soil greenhouse gas production.Annals of Environmental Science3,179–193. Sumner,M.E.,Miller,W.P.,1996.Cation exchange capacity and exchange coef?cients.

In:Sparks,D.L.,et al.(Ed.),Methods of Soil Analysis.Part3.Chemical Methods.SSSA Book Ser.5.Soil Science Society of America,Madison,WI,pp.1201–1229. Swift,R.S.,2001.Sequestration of carbon by soil.Soil Science166,858–871. Thomas,G.W.,1996.Soil pH and soil acidity.In:Sparks,D.L.,et al.(Ed.),Methods of Soil Analysis.Part3.Chemical Methods.SSSA Book Ser.5.Soil Science Society of America,Madison,WI,pp.475–490.Madison.WI.

Wilhelm,W.W.,Doran,J.W.,Power,J.F.,1986.Corn and soybean yield response to crop residue management under no-tillage production systems.Agronomy Journal78, 184–189.

Wilhelm,W.W.,Johnson,J.M.-F.,Hat?eld,J.L.,Voorhees,W.B.,Linden,D.R.,2004.Crop and soil productivity response to corn residue removal:a literature review.

Agronomy Journal96,1–17.

Yamato,M.,Okimori,Y.,Wibowo,I.F.,Anshiori,S.,Ogawa,M.,2006.Effects of the application of charred bark of Acacia mangium on the yield of maize,cowpea and peanut,and soil chemical properties in South Sumatra,Indonesia.Soil Science& Plant Nutrition52,489–495.

Yanai,Y.,Toyota,K.,Okazaki,M.,2007.Effects of charcoal addition on N2O emissions from soil resulting from rewetting air-dried soil in short-term laboratory experiments.Soil Science&Plant Nutrition53,181–188.

449

https://www.wendangku.net/doc/094841593.html,ird et al./Geoderma158(2010)443–449

on the contrary的解析

On the contrary Onthecontrary, I have not yet begun. 正好相反，我还没有开始。 https://www.wendangku.net/doc/094841593.html, Onthecontrary, the instructions have been damaged. 反之，则说明已经损坏。 https://www.wendangku.net/doc/094841593.html, Onthecontrary, I understand all too well. 恰恰相反，我很清楚 https://www.wendangku.net/doc/094841593.html, Onthecontrary, I think this is good. ⑴我反而觉得这是好事。 https://www.wendangku.net/doc/094841593.html, Onthecontrary, I have tons of things to do 正相反，我有一大堆事要做 Provided by jukuu Is likely onthecontrary I in works for you 反倒像是我在为你们工作 https://www.wendangku.net/doc/094841593.html, Onthecontrary, or to buy the first good. 反之还是先买的好。 https://www.wendangku.net/doc/094841593.html, Onthecontrary, it is typically american. 相反，这正是典型的美国风格。 222.35.143.196 Onthecontrary, very exciting.

恰恰相反，非常刺激。 https://www.wendangku.net/doc/094841593.html, But onthecontrary, lazy. 却恰恰相反，懒洋洋的。 https://www.wendangku.net/doc/094841593.html, Onthecontrary, I hate it! 恰恰相反，我不喜欢！ https://www.wendangku.net/doc/094841593.html, Onthecontrary, the club gathers every month. 相反，俱乐部每个月都聚会。 https://www.wendangku.net/doc/094841593.html, Onthecontrary, I'm going to work harder. 我反而将更努力工作。 https://www.wendangku.net/doc/094841593.html, Onthecontrary, his demeanor is easy and nonchalant. 相反，他的举止轻松而无动于衷。 https://www.wendangku.net/doc/094841593.html, Too much nutrition onthecontrary can not be absorbed through skin. 太过营养了反而皮肤吸收不了. https://www.wendangku.net/doc/094841593.html, Onthecontrary, I would wish for it no other way. 正相反，我正希望这样 Provided by jukuu Onthecontrary most likely pathological. 反之很有可能是病理性的。 https://www.wendangku.net/doc/094841593.html, Onthecontrary, it will appear clumsy. 反之，就会显得粗笨。 https://www.wendangku.net/doc/094841593.html,

英语造句

一般过去式时间状语：yesterday just now (刚刚) the day before three days ag0 a week ago in 1880 last month last year 1. I was in the classroom yesterday. I was not in the classroom yesterday. Were you in the classroom yesterday. 2. They went to see the film the day before. Did they go to see the film the day before. They did go to see the film the day before. 3. The man beat his wife yesterday. The man didn’t beat his wife yesterday. 4. I was a high student three years ago. 5. She became a teacher in 2009. 6. They began to study english a week ago 7. My mother brought a book from Canada last year. 8.My parents build a house to me four years ago . 9.He was husband ago. She was a cooker last mouth. My father was in the Xinjiang half a year ago. 10.My grandfather was a famer six years ago. 11.He burned in 1991

学生造句--Unit 1

●I wonder if it’s because I have been at school for so long that I’ve grown so crazy about going home. ●It is because she wasn’t well that she fell far behind her classmates this semester. ●I can well remember that there was a time when I took it for granted that friends should do everything for me. ●In order to make a difference to society, they spent almost all of their spare time in raising money for the charity. ●It’s no pleasure eating at school any longer because the food is not so tasty as that at home. ●He happened to be hit by a new idea when he was walking along the riverbank. ●I wonder if I can cope with stressful situations in life independently. ●It is because I take things for granted that I make so many mistakes. ●The treasure is so rare that a growing number of people are looking for it. ●He picks on the weak mn in order that we may pay attention to him. ●It’s no pleasure being disturbed whena I settle down to my work. ●I can well remember that when I was a child, I always made mistakes on purpose for fun. ●It’s no pleasure accompany her hanging out on the street on such a rainy day. ●I can well remember that there was a time when I threw my whole self into study in order to live up to my parents’ expectation and enter my dream university. ●I can well remember that she stuck with me all the time and helped me regain my confidence during my tough time five years ago. ●It is because he makes it a priority to study that he always gets good grades. ●I wonder if we should abandon this idea because there is no point in doing so. ●I wonder if it was because I ate ice-cream that I had an upset student this morning. ●It is because she refused to die that she became incredibly successful. ●She is so considerate that many of us turn to her for comfort. ●I can well remember that once I underestimated the power of words and hurt my friend. ●He works extremely hard in order to live up to his expectations. ●I happened to see a butterfly settle on the beautiful flower. ●It’s no pleasure making fun of others. ●It was the first time in the new semester that I had burned the midnight oil to study. ●It’s no pleasure taking everything into account when you long to have the relaxing life. ●I wonder if it was because he abandoned himself to despair that he was killed in a car accident when he was driving. ●Jack is always picking on younger children in order to show off his power. ●It is because he always burns the midnight oil that he oversleeps sometimes. ●I happened to find some pictures to do with my grandfather when I was going through the drawer. ●It was because I didn’t dare look at the failure face to face that I failed again. ●I tell my friend that failure is not scary in order that she can rebound from failure. ●I throw my whole self to study in order to pass the final exam. ●It was the first time that I had made a speech in public and enjoyed the thunder of applause. ●Alice happened to be on the street when a UFO landed right in front of her. ●It was the first time that I had kept myself open and talked sincerely with my parents. ●It was a beautiful sunny day. The weather was so comfortable that I settled myself into the

英语句子结构和造句

高中英语~词性~句子成分~语法构成第一章节：英语句子中的词性 1.名词：n. 名词是指事物的名称，在句子中主要作主语.宾语.表语.同位语。 2.形容词;adj. 形容词是指对名词进行修饰~限定~描述~的成份，主要作定语.表语.。形容词在汉语中是（的）.其标志是: ous. Al .ful .ive。. 3.动词：vt. 动词是指主语发出的一个动作，一般用来作谓语。 4.副词：adv. 副词是指表示动作发生的地点. 时间. 条件. 方式. 原因. 目的. 结果.伴随让步. 一般用来修饰动词. 形容词。副词在汉语中是（地）.其标志是：ly。 5.代词：pron. 代词是指用来代替名词的词，名词所能担任的作用，代词也同样.代词主要用来作主语. 宾语. 表语. 同位语。 6.介词：prep.介词是指表示动词和名次关系的词，例如：in on at of about with for to。其特征：

介词后的动词要用—ing形式。介词加代词时，代词要用宾格。例如：give up her（him）这种形式是正确的，而give up she（he）这种形式是错误的。 7.冠词：冠词是指修饰名词，表名词泛指或特指。冠词有a an the 。 8.叹词：叹词表示一种语气。例如：OH. Ya 等 9.连词：连词是指连接两个并列的成分，这两个并列的成分可以是两个词也可以是两个句子。例如：and but or so 。 10.数词：数词是指表示数量关系词，一般分为基数词和序数词第二章节：英语句子成分主语：动作的发出者，一般放在动词前或句首。由名词. 代词. 数词. 不定时. 动名词. 或从句充当。谓语：指主语发出来的动作，只能由动词充当，一般紧跟在主语后面。宾语：指动作的承受着，一般由代词. 名词. 数词. 不定时. 动名词. 或从句充当. 介词后面的成分也叫介词宾语。定语：只对名词起限定修饰的成分，一般由形容

六级单词解析造句记忆MNO

M A: Has the case been closed yet? B: No, the magistrate still needs to decide the outcome. magistrate n.地方行政官，地方法官，治安官 A: I am unable to read the small print in the book. B: It seems you need to magnify it. magnify vt.１．放大，扩大；２．夸大，夸张 A: That was a terrible storm. B: Indeed, but it is too early to determine the magnitude of the damage. magnitude n.１．重要性，重大；２．巨大，广大 A: A young fair maiden like you shouldn’t be single. B: That is because I am a young fair independent maiden. maiden n.少女，年轻姑娘，未婚女子 a.首次的，初次的 A: You look majestic sitting on that high chair. B: Yes, I am pretending to be the king! majestic a.雄伟的，壮丽的，庄严的，高贵的 A: Please cook me dinner now. B: Yes, your majesty, I’m at your service. majesty n.１．［Ｍ－］陛下（对帝王，王后的尊称）；２．雄伟，壮丽，庄严 A: Doctor, I traveled to Africa and I think I caught malaria. B: Did you take any medicine as a precaution? malaria n.疟疾 A: I hate you! B: Why are you so full of malice? malice n.恶意，怨恨 A: I’m afraid that the test results have come back and your lump is malignant. B: That means it’s serious, doesn’t it, doctor? malignant a.１．恶性的，致命的；２．恶意的，恶毒的 A: I’m going shopping in the mall this afternoon, want to join me? B: No, thanks, I have plans already. mall n.（由许多商店组成的）购物中心 A: That child looks very unhealthy. B: Yes, he does not have enough to eat. He is suffering from malnutrition.

base on的例句

意见应以事实为根据. 3 来自辞典例句 192. The bombers swooped ( down ) onthe air base. 轰炸机突袭空军基地. 来自辞典例句 193. He mounted their engines on a rubber base. 他把他们的发动机装在一个橡胶垫座上. 14 来自辞典例句 194. The column stands on a narrow base. 柱子竖立在狭窄的地基上. 14 来自辞典例句 195. When one stretched it, it looked like grey flakes on the carvas base. 你要是把它摊直, 看上去就象好一些灰色的粉片落在帆布底子上. 18 来自辞典例句 196. Economic growth and human well - being depend on the natural resource base that supports all living systems. 经济增长和人类的福利依赖于支持所有生命系统的自然资源. 12 1 来自辞典例句 197. The base was just a smudge onthe untouched hundred - mile coast of Manila Bay. 那基地只是马尼拉湾一百英里长安然无恙的海岸线上一个硝烟滚滚的污点. 6 来自辞典例句 198. You can't base an operation on the presumption that miracles are going to happen. 你不能把行动计划建筑在可能出现奇迹的假想基础上.

英语造句大全

英语造句大全English sentence 在句子中，更好的记忆单词！ 1、(1)、able adj. 能句子：We are able to live under the sea in the future. (2)、ability n. 能力句子：Most school care for children of different abilities. (3)、enable v. 使。。。能句子：This pass enables me to travel half-price on trains. 2、(1)、accurate adj. 精确的句子：We must have the accurate calculation. (2)、accurately adv. 精确地句子：His calculation is accurately. 3、(1)、act v. 扮演句子：He act the interesting character. （2）、actor n. 演员句子：He was a famous actor. (3)、actress n. 女演员句子：She was a famous actress. (4)、active adj. 积极的句子：He is an active boy. 4、add v. 加句子：He adds a little sugar in the milk. 5、advantage n. 优势句子：His advantage is fight. 6、age 年龄n. 句子：His age is 15. 7、amusing 娱人的adj. 句子：This story is amusing. 8、angry 生气的adj. 句子：He is angry. 9、America 美国n.

(完整版)主谓造句

主语+谓语 1. 理解主谓结构 1) The students arrived. The students arrived at the park. 2) They are listening. They are listening to the music. 3) The disaster happened. 2．体会状语的位置 1) Tom always works hard. 2) Sometimes I go to the park at weekends.. 3) The girl cries very often. 4) We seldom come here. The disaster happened to the poor family. 3. 多个状语的排列次序 1) He works. 2) He works hard. 3) He always works hard. 4) He always works hard in the company. 5) He always works hard in the company recently. 6) He always works hard in the company recently because he wants to get promoted. 4. 写作常用不及物动词 1. ache My head aches. I’m aching all over. 2. agree agree with sb. about sth. agree to do sth. 3. apologize to sb. for sth. 4. appear (at the meeting, on the screen) 5. arrive at / in 6. belong to 7. chat with sb. about sth. 8. come (to …) 9. cry 10. dance 11. depend on /upon 12. die 13. fall 14. go to … 15. graduate from 16. … happen 17. laugh 18. listen to... 19. live 20. rise 21. sit 22. smile 23. swim 24. stay (at home / in a hotel) 25. work 26. wait for 汉译英： 1.昨天我去了电影院。 2.我能用英语跟外国人自由交谈。 3.晚上7点我们到达了机场。 4.暑假就要到了。 5.现在很多老人独自居住。 6.老师同意了。 7.刚才发生了一场车祸。 8.课上我们应该认真听讲。9. 我们的态度很重要。 10. 能否成功取决于你的态度。 11. 能取得多大进步取决于你付出多少努力。 12. 这个木桶能盛多少水取决于最短的一块板子的长度。

初中英语造句

【it's time to和it's time for】 ——————这其实是一个句型,只不过后面要跟不同的东西. ——————It's time to跟的是不定式（to do）.也就是说,要跟一个动词,意思是“到做某事的时候了”.如： It's time to go home. It's time to tell him the truth. ——————It's time for 跟的是名词.也就是说,不能跟动词.如： It's time for lunch.(没必要说It's time to have lunch) It's time for class.(没必要说It's time to begin the class.) They can't wait to see you Please ask liming to study tonight. Please ask liming not to play computer games tonight. Don’t make/let me to smoke I can hear/see you dance at the stage You had better go to bed early. You had better not watch tv It’s better to go to bed early It’s best to run in the morning I am enjoy running with music. With 表伴随听音乐 I already finish studying You should keep working. You should keep on studying English Keep calm and carry on 保持冷静继续前行二战开始前英国皇家政府制造的海报名字 I have to go on studying I feel like I am flying I have to stop playing computer games and stop to go home now I forget/remember to finish my homework. I forget/remember cleaning the classroom We keep/percent/stop him from eating more chips I prefer orange to apple I prefer to walk rather than run I used to sing when I was young What’s wrong with you There have nothing to do with you I am so busy studying You are too young to na?ve I am so tired that I have to go to bed early

The Kite Runner-美句摘抄及造句

《The Kite Runner》追风筝的人--------------------------------美句摘抄 1.I can still see Hassan up on that tree, sunlight flickering through the leaves on his almost perfectly round face, a face like a Chinese doll chiseled from hardwood: his flat, broad nose and slanting, narrow eyes like bamboo leaves, eyes that looked, depending on the light, gold, green even sapphire 翻译：我依然能记得哈桑坐在树上的样子，阳光穿过叶子，照着他那浑圆的脸庞。他的脸很像木头刻成的中国娃娃，鼻子大而扁平，双眼眯斜如同竹叶，在不同光线下会显现出金色、绿色，甚至是宝石蓝。 E.g.: A shadow of disquiet flickering over his face. 2.Never told that the mirror, like shooting walnuts at the neighbor's dog, was always my idea. 翻译：从来不提镜子、用胡桃射狗其实都是我的鬼主意。E.g.:His secret died with him, for he never told anyone. 3.We would sit across from each other on a pair of high

翻译加造句

一、翻译 1. The idea of consciously seeking out a special title was new to me., but not without appeal. 让我自己挑选自己最喜欢的书籍这个有意思的想法真的对我具有吸引力。 2.I was plunged into the aching tragedy of the Holocaust, the extraordinary clash of good, represented by the one decent man, and evil. 我陷入到大屠杀悲剧的痛苦之中，一个体面的人所代表的善与恶的猛烈冲击之中。 3.I was astonished by the the great power a novel could contain. I lacked the vocabulary to translate my feelings into words. 我被这部小说所包含的巨大能量感到震惊。我无法用语言来表达我的感情（心情）。 4，make sth. long to short长话短说 5.I learned that summer that reading was not the innocent(简单的) pastime(消遣) I have assumed it to be., not a breezy, instantly forgettable escape in the hammock(吊床)，( though I’ ve enjoyed many of those too ). I discovered that a book, if it arrives at the right moment, in the proper season, will change the course of all that follows. 那年夏天，我懂得了读书不是我认为的简单的娱乐消遣，也不只是躺在吊床上，一阵风吹过就忘记的消遣。我发现如果在适宜的时间、合适的季节读一本书的话，他将能改变一个人以后的人生道路。二、词组造句 1. on purpose 特意，故意 This is especially true here, and it was ~. (这一点在这里尤其准确，并且他是故意的) 2.think up 虚构，编造，想出 She has thought up a good idea. 她想出了一个好的主意。 His story was thought up. 他的故事是编出来的。 3. in the meantime 与此同时助记：in advance 事前in the meantime 与此同时in place 适当地... In the meantime, what can you do? 在这期间您能做什么呢？ In the meantime, we may not know how it works, but we know that it works. 在此期间，我们不知道它是如何工作的，但我们知道，它的确在发挥作用。 4.as though 好像，仿佛 It sounds as though you enjoyed Great wall. 这听起来好像你喜欢长城。 5. plunge into 使陷入 He plunged the room into darkness by switching off the light. 他把灯一关，房

改写句子练习2标准答案

The effective sentences:(improve the sentences!) 1.She hopes to spend this holiday either in Shanghai or in Suzhou. 2.Showing/to show sincerity and to keep/keeping promises are the basic requirements of a real friend. 3.I want to know the space of this house and when it was built. I want to know how big this house is and when it was built. I want to know the space of this house and the building time of the house. 4.In the past ten years,Mr.Smith has been a waiter,a tour guide,and taught English. In the past ten years,Mr.Smith has been a waiter,a tour guide,and an English teacher. 5.They are sweeping the floor wearing masks. They are sweeping the floor by wearing masks. wearing masks,They are sweeping the floor. 6.the drivers are told to drive carefully on the radio. the drivers are told on the radio to drive carefully 7.I almost spent two hours on this exercises. I spent almost two hours on this exercises. 8.Checking carefully,a serious mistake was found in the design. Checking carefully,I found a serious mistake in the design.

用以下短语造句

M1 U1 一. 把下列短语填入每个句子的空白处（注意所填短语的形式变化）： add up (to) be concerned about go through set down a series of on purpose in order to according to get along with fall in love (with) join in have got to hide away face to face 1 We’ve chatted online for some time but we have never met ___________. 2 It is nearly 11 o’clock yet he is not back. His mother ____________ him. 3 The Lius ___________ hard times before liberation. 4 ____________ get a good mark I worked very hard before the exam. 5 I think the window was broken ___________ by someone. 6 You should ___________ the language points on the blackboard. They are useful. 7 They met at Tom’s party and later on ____________ with each other. 8 You can find ____________ English reading materials in the school library. 9 I am easy to be with and _____________my classmates pretty well. 10 They __________ in a small village so that they might not be found. 11 Which of the following statements is not right ____________ the above passage? 12 It’s getting dark. I ___________ be off now. 13 More than 1,000 workers ___________ the general strike last week. 14 All her earnings _____________ about 3,000 yuan per month. 二.用以下短语造句： 1.go through 2. no longer/ not… any longer 3. on purpose 4. calm… down 5. happen to 6. set down 7. wonder if 三. 翻译： 1.曾经有段时间，我对学习丧失了兴趣。（there was a time when…） 2. 这是我第一次和她交流。（It is/was the first time that …注意时态） 3.他昨天公园里遇到的是他的一个老朋友。（强调句） 4. 他是在知道真相之后才意识到错怪女儿了。（强调句） M 1 U 2 一. 把下列短语填入每个句子的空白处（注意所填短语的形式变化）： play a …role (in) because of come up such as even if play a …part (in) 1 Dujiangyan(都江堰) is still ___________in irrigation(灌溉) today. 2 That question ___________ at yesterday’s meeting. 3 Karl Marx could speak a few foreign languages, _________Russian and English. 4 You must ask for leave first __________ you have something very important. 5 The media _________ major ________ in influencing people’s opinion s. 6 _________ years of hard work she looked like a woman in her fifties. 二.用以下短语造句： 1.make (good/full) use of 2. play a(n) important role in 3. even if 4. believe it or not 5. such as 6. because of

英语造句

English sentence 1、(1)、able adj. 能句子：We are able to live under the sea in the future. (2)、ability n. 能力句子：Most school care for children of different abilities. (3)、enable v. 使。。。能句子：This pass enables me to travel half-price on trains. 2、(1)、accurate adj. 精确的句子：We must have the accurate calculation. (2)、accurately adv. 精确地句子：His calculation is accurately. 3、(1)、act v. 扮演句子：He act the interesting character.（2）、actor n. 演员句子：He was a famous actor. (3)、actress n. 女演员句子：She was a famous actress. (4)、active adj. 积极的句子：He is an active boy. 4、add v. 加句子：He adds a little sugar in the milk. 5、advantage n. 优势句子：His advantage is fight. 6、age 年龄n. 句子：His age is 15. 7、amusing 娱人的adj. 句子：This story is amusing. 8、angry 生气的adj. 句子：He is angry. 9、America 美国n. 句子：He is in America. 10、appear 出现v. He appears in this place. 11. artist 艺术家n. He is an artist. 12. attract 吸引 He attracts the dog. 13. Australia 澳大利亚 He is in Australia. 14.base 基地 She is in the base now. 15.basket 篮子 His basket is nice. 16.beautiful 美丽的 She is very beautiful. 17.begin 开始 He begins writing. 18.black 黑色的 He is black. 19.bright 明亮的 His eyes are bright. 20.good 好的 He is good at basketball. 21.British 英国人 He is British. 22.building 建造物 The building is highest in this city 23.busy 忙的 He is busy now. 24.calculate 计算 He calculates this test well. 25.Canada 加拿大 He borns in Canada. 26.care 照顾 He cared she yesterday. 27.certain 无疑的 They are certain to succeed. 28.change 改变 He changes the system. 29.chemical 化学药品