Heavy metal availability and impact on activity of soil microorganisms along a Cu/Zn contamination gradient

All the regulations that define a maximum concentration of metals in the receiving soil are based on total soil metal concentration. However, the potential toxicity of a heavy metal in the soil depends on its speciation and availability. We studied the effects of heavy metal speciation and availability on soil microorganism activities along a Cu/Zn contamination gradient. Microbial biomass and enzyme activity of soil contaminated with both Cu and Zn were investigated. The results showed that microbial biomass was negatively affected by the elevated metal levels. The microbial biomass-C （Cmic）/organic C （Corg） ratio was closely correlated to heavy metal stress. There were negative correlations between soil microbial biomass, phosphatase activity and NH4NO3 extractable heavy metals. The soil microorganism activity could be predicted using empirical models with the availability of Cu and Zn. We observed that 72% of the variation in phosphatase activity could be explained by the NH4NO3-extractable and total heavy metal concentration. By considering different monitoring approaches and different viewpoints, this set of methods applied in this study seemed sensitive to site differences and contributed to a better understanding of the effects of heavy metals on the size and activity of microorganisms in soils. The data presented demonstrate the relationship between heavy metals availability and heavy metal toxicity to soil microorganism along a contamination gradient.     

土壤-青菜系统中铅污染对土壤微生物活性及多样性的影响

采用盆栽方法研究了青菜种植条件下2种不同类型的人为铅污染土(黄松田土和黄红壤)中不同处理对土壤微生物生物量、生理生态参数以及群落结构的影响.结果表明,2种土壤在外源铅含量为100和300 mg·kg-1时,土壤微生物生物量有微小增加,而高浓度铅污染使土壤微生物生物量显著降低.在高浓度铅污染土壤中,微生物生理生态参数发生明显变化,微生物生物量碳/土壤有机质碳(Cmic/Corg)逐渐下降,代谢熵(qco2)明显上升,表明土壤微生物群落处于胁迫状态.结果还显示,铅污染对土壤微生物的影响与不同的管理方式(青菜种植情况)以及土壤中有机质、粘粒含量等有关,在种植青菜、有机质和粘粒含量高的土壤中,土壤微生物各项参数变化要小.对21种磷脂脂肪酸(PLFA)的图谱进行分析,结果表明,受铅污染土壤的微生物群落结构组成伴随着功能参数的变化而发生了改变;随着铅污染程度的增强,指示真菌和放线菌类的脂肪酸增加,而革兰氏阳性菌与革兰氏阴性菌脂肪酸比值下降.     

重金属铜、锌、镉、铅复合污染对土壤环境微生物群落的影响

以铜锌冶炼厂附近的水稻土为例 ,研究了重金属复合污染对土壤微生物群落的影响 .结果表明 ,有效铜、锌、镉、铅与微生物生物量碳、微生物生物量氮、微生物商、微生物生物量氮 全氮均呈显著负相关 .重金属污染均能降低细菌、真菌和放线菌的数量 .用BIOLOG生态盘研究了重金属污染对微生物群落结构的影响 ,发现重金属污染明显影响了微生物群落结构 ,反映在典型变量 1(CV1)与重金属元素含量呈极显著正相关 ,因此认为典型变量 1是反映重金属污染程度的有效指标 .经逐步回归分析发现 ,有效铜是影响典型变量 1最主要的因素 .     

铅锌尾矿砂污染下的岩溶土壤微生物群落碳源代谢特征

以广西阳朔思的村铅锌矿尾砂污染的水稻田、玉米地、柑橘园以及对照(旱地)土壤为研究对象,采用碳素利用法和18S rRNA变性梯度凝胶电泳技术探究岩溶区重金属污染下土壤微生物群落碳源代谢特征以及土壤真菌与土壤有机碳的交互关系.结果表明,广西阳朔思的村铅锌矿尾砂污染区土壤重金属总体含量(Pb、Zn、Cu、Cd)依次为:水稻田玉米地柑橘园对照;同时地累积综合指数显示该区重金属污染以Pb、Cd为主,其中Cd带来的环境风险最高.受Pb、Zn、Cu、Cd等重金属复合污染物影响,土壤微生物生物量碳、微生物熵和碳源代谢速率表现出随总体重金属质量分数增加而降低的变化规律,但土壤总有机碳质量分数却表现为:水稻田对照柑橘园或玉米地.DGGE结果进一步显示对照组土壤存在担子菌门多孔菌目Pycnoporus sp.ZW02.30,柑橘园和玉米地土壤存在镰刀菌属Fusarium solani和Fusarium oxysporum以及柑橘园土壤存在青霉属Penicillium decumbens.然而,上述参与淀粉、纤维素、半纤维素、木质素等糖类降解过程的真菌没有在水稻田土壤检出.加之,水稻田土壤微生物功能多样性指数和微生物熵最低而土壤有机碳质量分数最高,说明铅锌尾矿砂通过影响不同样地土壤微生物糖类代谢过程,进而调节土壤碳在微生物特别是真菌作用下的矿化速率.     

Effect of heavy metals on soil microbial activity and diversity in a reclaimed mining wasteland of red soil area

The microbial biomass, basal respiration and substrate utilization pattern in copper mining wasteland of red soil area, southern China, were investigated. The results indicated that soil microflora were obviously different compared with that of the non-mine soil. Microbial biomass and basal respiration were negatively affected by the elevated heavy metal levels. Two important microbial ecophysiological parameters, namely, the ratio of microbial biomass C（ Cmic ）/organic C（ Corg ） and metabolic quotient（qCO2 ） were closely correlated to heavy metal stress. There was a significant decrease in the Cmic/Corg ratio and an increase in the metabolic quotient with increasing metal concentration. Multivariate analysis of Biolog data for sole carbon source utilization pattern demonstrated that heavy metal pollution had a significant impact on microbial community structure and functional diversity. All the results showed that soil microbiological parameters had great potential to become the early sensitive, effective and liable indicators of the stresses or perturbations in soils of mining ecosystems.     

Organic carbon accumulation capability of two typical tidal wetland soils in Chongming Dongtan, China

We measured organic carbon input and content of soil in two wetland areas of Chongming Dongtan (Yangtze River Estuary) to evaluate variability in organic carbon accumulation capability in di erent wetland soils. Observed di erences were investigated based on the microbial activity and environmental factors of the soil at the two sites. Results showed that the organic carbon content of wetland soil vegetated with Phragmites australis (site A) was markedly lower than that with P. australis and Spartina alterniflora (site B). Sites di erences were due to higher microbial activity at site A, which led to higher soil respiration intensity and greater carbon outputs. This indicated that the capability of organic carbon accumulation of the site B soils was greater than at site A. In addition, petroleum pollution and soil salinity were di erent in the two wetland soils. After bio-remediation, the soil petroleum pollution at site B was reduced to a similar level of site A. However, the culturable microbial biomass and enzyme activity in the remediated soils were also lower than at site A. These results indicated that greater petroleum pollution at site B did not markedly inhibit soil microbial activity. Therefore, di erences in vegetation type and soil salinity were the primary factors responsible for the variation in microbial activity, organic carbon output and organic carbon accumulation capability between site A and site B.     

影响土壤重金属生物毒性的若干因子

本文应用发光细菌法探讨了土壤类型、粘土矿物、无定形金属氧化物、吸附剂对重金属纯溶液以及重金属污染土壤的降毒效应.红壤、砖红壤对Cu、Cd、Pb呈现负的降毒效应,而对As具有明显的降毒作用.黑土、黄棕壤对供试阳离子金属具有明显的降毒效应,对As降毒却不明显.试验证明粘土矿物及其组成是影响土壤重金属毒性的最基本因素.无定形氧化锰对供试阳离子金属的降毒能力大于无定形氧化铁,对As的效应二者则相反.不同吸附剂对Cu、Cd、Pb呈现基本相同的降毒顺序,即炉烟灰>活性炭>泥炭>干活性污泥,不同配比吸附剂对红壤添加性阳离子和东乡铜矿污染土壤均具有明显的降毒作用.添加吸附剂的东乡铜矿污染土壤随着土壤溶液毒性的消除,随之也消除或减轻了其对水稻种芽的急性毒害.     

科尔沁沙地和浑善达克沙地流动沙丘中土壤微生物学特征比较

通过对科尔沁沙地和浑善达克沙地流动沙丘中0～10 cm和>10～20 cm层土壤中微生物数量和生物量碳的比较表明:土壤微生物三大类群(细菌、放线菌和真菌)数量和微生物生物量碳均表现为浑善达克沙地 > 科尔沁沙地,其中两大沙地真菌数量差异显著,细菌和放线菌数量差异不显著,微生物生物量碳差异显著;两大沙地土壤微生物数量和生物量碳在不同土壤层次均表现为>10～20 cm 层高于 0～10 cm层,其中微生物三大类群数量差异均不显著,微生物生物量碳差异显著. 土壤性质的差异导致两大沙地流动沙丘中微生物数量和生物量碳略有不同. 细菌和真菌数量与土壤有机碳和土壤全氮呈显著正相关,与土壤水分含量和pH呈显著负相关,微生物生物量碳与土壤有机碳和土壤全氮呈显著正相关. 两大沙地土壤微生物与土壤养分的层化比率均小于1,科尔沁沙地中微生物数量、生物量碳和土壤养分的层化比率均大于浑善达克沙地,可以推断两大沙地的流动沙丘处于退化状态,而且浑善达克沙地退化速度更快.      

Restoring the plant productivity of heavy metal-contaminated soil using phosphate sludge, marble waste, and beneficial microorganisms

Assisted natural remediation (ANR) has been highlighted as a promising, less expensive, and environmentally friendly solution to remediate soil contaminated with heavy metals. We tested the effects of three amendments (10% compost, C; 5 or 15% phosphate sludge, PS5 and PS15; and 5 or 15% marble waste, MW5 and MW15) in combination with microorganism inoculation (rhizobacteria consortium alone, mycorrhizae alone, and the two in-combination) on alfalfa in contaminated soil. Plant concentrations of Zn, Cu, and Pb were measured, along with proline and malondialdehyde production. The microbiological and physicochemical properties of the mining soil were evaluated. Application of the amendments allowed germination and promoted growth. Inoculation with the rhizobacteria consortium and/or mycorrhizae stimulated plant growth. PS and MW stimulated the production of proline. Inoculation of alfalfa with the rhizobacteria-mycorrhizae mixture and the application of MW allowed the safe cultivation of the legume, as shown by the low concentrations of metals in plant shoots. Zn and Pb concentrations were below the limits recommended for animal grazing and accumulated essentially in roots. Soil analyses showed the positive effect of the amendments on the soil physicochemical properties. All treatments increased soil pH (around 7), total organic carbon, and assimilable phosphorus content. Notably, an important decrease in soluble heavy metals concentrations was observed. Overall, our findings revealed that the applied treatments reduced the risk of metal-polluted soils limiting plant growth. The ANR has great potential for success in the restoration of polymetallic and acidic mining soils using the interaction between alfalfa, microorganisms, and organo-mineral amendments.     

太湖地区3种水稻土不同温度培养中有机碳库变化及其对升温的响应

全球变暖下土壤有机碳储存的变化是土壤与全球变化研究的热点问题.本研究选择了3种太湖地区代表性水稻土的表层土壤,分别进行20℃和25℃的室内恒温培养,监测培养过程中总有机碳、溶解性有机碳和微生物量碳的变化动态,试图了解这些土壤的有机碳分解过程对全球变暖的响应特点.结果表明,这些土壤培养中总有机碳变化可以用一级衰变动力学方程或对数衰减方程描述,但动力学特征依培养温度的不同而异.升温大大促进了铁渗水耕人为土和潜育水耕人为土中有机碳的分解与呼吸损失,而铁聚水耕人为土没有显著变化.供试土壤总有机碳损失的Q₁₀系数分别为:潜育水耕人为土(11.1～14.1)＞铁渗水耕人为土(4.4～6.4)＞铁聚水耕人为土(0.63～0.73).这一方面说明温度敏感性在同一地带的不同土壤间的差异超过文献上报道的不同气候带的差异,但另一方面揭示了水稻土可能是一类对全球升温敏感响应的人为土.溶解性有机碳和微生物量的碳的变化还提示不同温度培养下水稻土微生物群落结构可能改变,因而影响到土壤有机碳库的生物有效性在温度条件下的变化.可以认为,土壤升温下有机碳的变化不但与土壤有机碳的性质有关,而且与土壤性质控制下的生物条件的改变有关.故土壤升温下有机碳的损失不仅仅是温度对分解过程的反应速度的影响.当然,对于不同土壤间的这种差异还需从有机碳-土壤环境-土壤生物的相互关系上做进一步的工作.     

铸造废砂的环境毒性研究

采用毒性特性浸出程序、顶空气相色谱技术检测了5种铸造废砂中的重金属与有机污染物,采用发光细菌毒性检测技术和土壤酶活性实验研究了废砂的生物效应.结果表明,由于浇注金属与造型材料的不同,5种铸造废砂中的金属与有机污染物成分和浓度均有较大差异.其中,铸铁与铸钢废砂浸出液中的铁离子,铸铝废砂中的As离子超出了《地表水环境标准》规定的最大允许检出浓度.5种废砂中的有机污染物种类十分复杂,对发光细菌表现出不同程度的抑菌活性,发光强度的抑制率在30%～95%之间.此外,土壤酶活性实验结果表明,废砂中的金属污染物可能会抑制土壤中微生物的活性,而有机物则对土壤微生物的活性有一定的促进作用.因此,铸造废砂的随意排放将会对环境造成较严重的威胁.     

Effect of copper on phospholipid fatty acid composition of microbial communities in two red soils

The phospholipid fatty acid （PLFA） composition was analyzed in two red soils experimentally contaminated with copper at different concentrations. The total amounts ofphospholipid fatty acids （PLFAs） in both red soils were significantly correlated with soil microbial biomass C and N, which decreased consistently with increasing levels of copper. The relative quantities of the PLFAs 17：0 （10 Me）, i16：0, il 5：0 and 16：1w5c, decreased with increasing heavy metal concentration, while those of cyl7：0, which is an indicator of gram-negative bacteria, increased. The Shannon index calculated from the PLFA data indicated that Cu addition in the red soils decreased the population diversity of soil microbial communities. Multivariate analysis of PLFA data demonstrated that high levels of Cu application had a significant impact on microbial community structure and there is a threshold metal concentration for PLFA composition. Comparatively higher toxic effect on microbial biomass and community structure were found in the red sandy soil than those in the red clayey soil. The differential effect of Cu addition on microbial communities in the two soils may be due to differences in soil texture and cation exchange capacity.     

宁南山区林地土壤原位矿化过程中碳氮转化耦合特征

为了解宁南山区典型植被恢复模式之一——人工林地土壤碳氮转化的特征以及二者的关系,运用PVC顶盖埋管法进行1 a的原位矿化培养实验,每隔2个月采样,研究柠条、山桃、山杏林地中土壤有机碳、可溶性有机碳和微生物量碳与土壤有机氮、无机氮以及净氨化速率、净硝化速率、净矿化速率和微生物固定速率在一年中的变化特征以及碳氮耦合关系.结果表明在原位培养过程中,61~120 d碳氮的变化最明显,主要受到土壤水分的影响;土壤有机碳和全氮极显著正相关,土壤微生物量碳氮、可溶性有机碳氮显著正相关;土壤有机碳转化速率显著影响净氨化速率、净硝化速率和MBN转化速率,且符合一元线性回归方程;柠条地培养一年后土壤微生物商(MBC/SOC)、MBN/SON显著升高,而且净硝化速率、净矿化速率显著大于山桃和山杏.     

不同施肥措施对土壤活性有机碳的影响

采用田间试验,研究了不同施肥措施下,华北冬小麦-夏玉米轮作体系中潮土土壤活性有机碳含量及组分的变化特征.结果表明,施肥显著增加土壤水溶性有机碳和易氧化有机碳含量,与不施肥相比,增加幅度分别为24.92～38.63 mg·kg-1和0.94～0.58 g·kg-1,其中单施有机肥对土壤水溶性有机碳含量增加作用大于配施化肥和化肥单施,单施有机肥或与化肥配施对土壤易氧化有机碳的提升效果优于单施化肥.有机肥或化肥单施对土壤微生物量碳没有显著促进作用,而有机肥与化肥配施土壤微生物量碳含量分别增加36.06%和20.69%;土壤易氧化有机碳、水溶性有机碳和微生物量碳占总有机碳的比例变化范围分别为8.41%～14.83%、0.47%～0.70%和0.89%～1.20%,施肥显著提高了土壤水溶性有机碳和易氧化有机碳比例,不同施肥措施对水溶性有机碳的提升效应没有显著差异.有机肥与化肥配施对易氧化有机碳的比例提升作用大于有机肥或化肥单施,同时显著增加土壤微生物量碳比例,但有机肥或化肥单施对土壤微生物量碳比例没有显著作用.可见,在试验地条件下,有机肥与化肥的适当配施对于增加土壤活性有机碳含量和有效调控其关键组分具有重要作用.     

2种组配改良剂对稻田土壤重金属有效性的效果

为研究2种组配改良剂LS(碳酸钙+海泡石)和HZ(羟基磷灰石+沸石)对土壤重金属的生物有效性以及水稻吸收累积重金属的影响,在湘南某矿区附近污染稻田中施用了不同添加量(0,2,4,8g/kg)的两种组配改良剂,并进行了水稻种植的田间试验.结果表明,施用2~8g/kg组配改良剂LS和HZ均能使土壤pH值和CEC含量显著增加,有机质含量变化不明显,LS比HZ更能提高土壤pH值和CEC含量.施用2~8g/kg组配改良剂LS能使土壤中Pb、Cd、Cu和Zn的TCLP提取态含量分别降低25.7%~52.2%、12.7%~25.7%、6.4%~17.2%和8.6%~23.4%,施用2~8g/kg HZ使土壤中Pb、Cd、Cu和Zn的TCLP提取态含量分别降低57.6%~80.1%、7.0%~40.9%、2.3%~22.7%和4.5%~33.2%.两种组配改良剂能显著降低土壤中Pb、Cd、Cu和Zn的生物有效性,抑制水稻植株对Pb和Cd的吸收,土壤Pb、Cd和Cu的TCLP提取态含量与水稻根系和糙米中Pb、Cd和Cu的含量之间存在显著或极显著的正相关关系,TCLP提取态含量能较好的表示重金属在土壤中的生物有效性.     

生物质炭对双季稻水稻土微生物生物量碳、氮及可溶性有机碳氮的影响

生物质炭可影响土壤微生物量,但生物质炭对双季稻田土壤微生物生物量碳、氮(MBC、MBN)及可溶性有机碳、氮(DOC、DON)的影响还不清楚.基于此,本研究选取亚热带2种典型双季稻田土壤(花岗岩母质发育的水稻土S1和第四纪红壤发育的水稻土S2)作为研究对象,开展室内培养试验来研究不施氮肥条件下生物质炭添加对土壤微生物生物量碳、氮及可溶性有机碳、氮的影响.每种土壤设置3个小麦秸秆生物质炭添加量,即土重的0%、1%和2%,分别用CK、LB和HB表示.培养70 d后,2种水稻土的MBC均值:S1为877. 03、832. 11和849. 30 mg·kg~(-1),S2为902. 94、874. 19和883. 22mg·kg~(-1). S1+LB、S1+HB和S2+LB均显著降低了土壤MBC均值(P 0. 05),这可能是由生物质炭吸附土壤有机碳及其他有机物,阻碍了微生物的生长而造成的. S1土壤中低生物质炭添加量较对照显著降低了土壤MBN均值(P 0. 05),降幅达9. 45%.生物质炭对S1土壤MBC/MBN均值影响不明显,但LB降低了S2土壤MBC/MBN均值(P 0. 05).由于生物质炭本身含有部分可溶性有机碳及其高p H值,添加到2种水稻土中均增加了土壤DOC均值,增幅分别达4. 42%～22. 20%和10. 57%～35. 47%.但生物质炭(除S2+HB处理)显著降低了土壤DON均值,这可能归因于生物质炭对土壤有机氮的吸附作用及生物质炭本身有机碳分解过程中对N的消耗作用.生物质炭显著增加了2种水稻土的DOC/DON均值,且随着生物质炭添加量的增加而增加.综上所述,在双季稻田土壤中单施生物质炭虽然可增加土壤可溶性有机碳,但对土壤微生物量有一定的降低作用,且会加重土壤氮亏缺状况.因此,在亚热带双季稻田中生物质炭应与化肥等配合施用.     

土壤自养微生物同化碳向土壤有机碳库输入的定量研究：14C连续标记法

自养微生物在土壤中广泛存在,但其CO2同化能力及其向土壤碳库的输入机制尚不明确.应用14C连续标记示踪技术,选取亚热带区4种典型稻田土壤在密闭系统模拟培养,探讨了土壤自养微生物同化碳向土壤碳库的输入过程和机制及其对土壤碳库活性组分的影响.结果表明,土壤微生物具有客观的CO2同化能力.标记培养110 d后,供试土壤的14C-SOC含量范围为69.06～133.81 mg.kg-1,而14C-DOC、14C-MBC含量范围为2.54～8.10 mg.kg-1、19.50～49.16 mg.kg-1.土壤自养微生物同化碳(14C-SOC)与其微生物截留碳(14C-MBC)呈极显著的正相关关系.土壤可溶解性有机碳(DOC)、微生物量碳(MBC)和SOC的更新率分别为5.65%～24.91%、4.23%～20.02%和0.58%～0.92%.而且,土壤自养微生物同化碳的输入对土壤活性碳组分的DOC、MBC含量变化影响较大,而对SOC影响较小.对微生物在土壤碳循环过程的基本功能的认识在本研究中得以丰富和加深.     

三峡库区典型消落带土壤微生物生物量碳、氮的变化特征及其影响因素探讨

本文以三峡库区王家沟一典型消落带为研究对象,选择180、175、165和155 m这4个高程以探讨水位变化对土壤微生物生物量碳(SMBC)和微生物生物量氮(SMBN)的影响.其中,175、165和155m高程坐落在消落带内,分别表现为短、中和长期淹水,180 m高程作为对照,为永不淹水的陆地.土壤样品的采集深度为0~20 cm,每周采集一次.结果表明,180 m高程处土壤有机碳(SOC)和全氮(TN)均无明显的季节变化,而175 m高程处SOC和TN季节变化明显,表现为春夏季高于秋冬季;各高程上的SMBC和SMBN及其分配比例呈现出秋高夏低的季节变化形态,表明消落带夏季高温低湿的土壤环境限制了微生物活性及土壤有机碳氮的周转速率.数据分析表明,与180 m高程相比,消落带上的175 m和165 m高程SOC、TN、SMBC及微生物商、SMBN及其分配比例均得到不同程度的升高,而155 m高程除了SMBN及其分配比例与对照无显著差异外,其他指标均显著低于对照,表明与未淹水对照点相比较,中短期淹水有利于提高消落带土壤碳氮含量及周转速率和微生物生物量,而长期受到江水淹没胁迫的土壤则会抑制土壤碳氮以及SMBC含量,并降低SOC的周转速率.相关分析表明,SMBC和SMBN均与地下5 cm处温度和p H呈极显著负相关,说明地下5cm处的温度以及p H对土壤微生物生物量有强烈的影响.     

Soil resource availability impacts microbial response to organic carbon and inorganic nitrogen inputs

Impacts of newly added organic carbon （C） and inorganic nitrogen （N） on the microbial utilization of soil organic matter are important in determining the future C balance of terrestrial ecosystems. We examined microbial responses to cellulose and ammonium nitrate additions in three soils with very different C and N availability. These soils included an organic soil（ 14.2% total organic C, with extremely high extractable N and low labile C）, a forest soi1（4.7% total organic C, with high labile C and extremely low extractable N）, and a grassland soil（1.6% total organic C, with low extractable N and labile C）. While cellulose addition alone significantly enhanced microbial respiration and biomass C and N in the organic and grassland soils, it accelerated only the microbial respiration in the highly-N limited forest soil. These results indicated that when N was not limited, C addition enhanced soil respiration by stimulating both microbial growth and their metabolic activity, New C inputs lead to elevated C release in all three soils, and the magnitude of the enhancement was higher in the organic and grassland soils than the forest soil. The addition of cellulose plus N to the forest and grassland soils initially increased the microbial biomass and respiration rates, but decreased the rates as time progressed. Compared to cellulose addition alone, cellulose plus N additions increased the total C-released in the grassland soil, but not in the forest soil. The enhancement of total C- released induced by C and N addition was less than 50% of the added-C in the forest soil after 96 d of incubation, in contrast to 87.5% and 89.0% in the organic and grassland soils. These results indicate that indigenous soil C and N availability substantially impacts the allocation of organic C for microbial biomass growth and/or respiration, potentially regulating the turnover rates of the new organic C inputs.     

生物质炭和秸秆配合施用对土壤有机碳转化的影响

为探讨生物质炭和秸秆碳输入对土壤碳构成和转化的影响,通过室内培养试验,研究了单施生物质炭、秸秆及两者配合施入下土壤二氧化碳的释放特征以及土壤微生物碳和有机碳的变化.结果表明,秸秆有机碳在土壤中的矿化率为21.50%(2%添加水平),远大于等量生物质炭的矿化率(8.09%);施用等量(占4%土重)生物质炭和秸秆,培养200 d后土壤有机碳含量分别为24.40 g·kg~(-1)、17.40 g·kg~(-1),表明生物质炭对有机碳的提升作用大于秸秆的.施用生物质炭对土壤固有有机碳有一定的保护作用,生物质炭与秸秆配合施用促进了秸秆的矿化,对有机碳矿化影响的交互效应为正值.施用秸秆能大幅度增加土壤微生物碳,而生物质炭对土壤微生物碳影响小;秸秆和生物质炭配合也增加了土壤微生物碳,但其交互效应与培养时间、施用量等有关,可正可负.