Partitioning of Zn,Cd, Pb,and Cu in organic-rich soil profiles in the vicinity of a zinc smelter

Abstract

A five-step sequential extraction procedure was applied to organic-rich soil samples from five soil profiles situated 1–8 km from a zinc smelter. The partitioning of Zn, Cd, Pb, and Cu into five operationally defined fractions (exchangeable, “carbonate’’-bound, reducible, oxidizable, and residual) was studied at different soil depths down to 35cm. In the surface soil (0–1 cm) a major part of Pb and Cu was extracted in the oxidizable fraction, whereas for Zn and Cd slightly more was extracted in the ‘‘carbonate”-fraction than in the other four fractions. Extracted metal proportions in the oxidizable fraction were respectively of the order of 30%, 20%, 50%, and 80% for Zn, Cd, Pb, and Cu in the surface soil for all sites, but these proportions decreased with soil depth. In the surface soil less than 20% of all the elements were extracted in the residual fraction, but the proportions associated with this fraction generally increased with soil depth. In the C-horizon, differences in extracted proportions of Pb and Cu in the residual fraction were probably due to geochemical factors, whereas for Zn the low extracted proportion at a highly contaminated site (20%) may be due to Zn migration to the C-horizon at this site. For Cd the extracted proportions in the C-horizon were lower than for the other elements, generally below 20%, presumably because Cd is weaker in terms of its adsorption to the soil than the other elements studied. Total concentrations of the metals decreased strongly with increasing distance from the smelter, but less systematic differences were observed for their distributions among fractions. Potentially bioavailable metal proportions (exchangeable + “carbonate”-bound fraction) in the surface soil were about 50%, 60%, 20%, and 10% for Zn, Cd, Pb, and Cu, respectively. In C-horizon soil the mobility sequence Cd>Zn>Pb = Cu was generally observed. The present results indicate that the concentrations and chemical fractionation of Zn, Pb, and Cd in these soils represent a considerable risk to natural terrestrial food chains.     

Detection of Arcobacter spp. in piggery effluent and effluent-irrigated soils in southeast Queensland

AIMS: To investigate the occurrence and levels of Arcobacter spp. in pig effluent ponds and effluent-treated soil. METHODS AND RESULTS: A Most Probable Number (MPN) method was developed to assess the levels of Arcobacter spp. in seven pig effluent ponds and six effluent-treated soils, immediately after effluent irrigation. Arcobacter spp. levels in the effluent ponds varied from 6.5 x 10(5) to 1.1 x 10(8) MPN 100 ml(-1) and in freshly irrigated soils from 9.5 x 10(2) to 2.8 x 10(4) MPN g(-1) in all piggery environments tested. Eighty-three Arcobacter isolates were subjected to an abbreviated phenotypic test scheme and examined using a multiplex polymerase chain reaction (PCR). The PCR identified 35% of these isolates as Arcobacter butzleri, 49% as Arcobacter cryaerophilus while 16% gave no band. All 13 nonreactive isolates were subjected to partial 16S rDNA sequencing and showed a high similarity (>99%) to Arcobacter cibarius. CONCLUSIONS: A. butzleri, A. cryaerophilus and A. cibarius were isolated from both piggery effluent and effluent-irrigated soil, at levels suggestive of good survival in the effluent pond. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to provide quantitative information on Arcobacter spp. levels in piggery effluent and to associate A. cibarius with pigs and piggery effluent environments.     

Phytoremediation of Cd,Ni, Pb and Zn by Salvinia minima

Most metals disperse easily in environments and can be bioconcentrated in tissues of many organisms causing risks to the health and stability of aquatic ecosystems even at low concentrations. The use of plants to phytoremediation has been evaluated to mitigate the environmental contamination by metals since they have large capacity to adsorb or accumulate these elements. In this study we evaluate Salvinia minima growth and its ability to accumulate metals. The plants were cultivated for about 60 days in different concentrations of Cd, Ni, Pb and Zn (tested alone) in controlled environmental conditions and availability of nutrients. The results indicated that S. minima was able to grow in low concentrations of selected metals (0.03 mg L^?1 Cd, 0.40 mg L^?1 Ni, 1.00 mg L^?1 Pb and 1.00 mg L^?1 Zn) and still able to adsorb or accumulate metals in their tissues when cultivated in higher concentrations of selected metals without necessarily grow. The maximum values of removal metal rates (mg m² day^?1) for each metal (Cd = 0.0045, Ni = 0.0595, Pb = 0.1423 e Zn = 0.4046) are listed. We concluded that S. minima may be used as an additional tool for metals removal from effluent.     

生长在铅锌矿废水污灌区的长豇豆组织中Pb、Zn、Cd含量的品种间差异

在经铅锌矿废水灌溉约50年的农田中种植24个长豇豆品种,测定植物体内的Pb、Zn、Cd在根、茎、叶及果实中的含量。结果表明,Cd在长豇豆根、茎、叶及果实的平均含量分别为1．212、0．425、1．051mg·kg^-1和0．011mg·kg^-1;Pb则分别是92．53、9．79、33．08mg·kg^-1和0．120mg·kg^-1;Zn分别是130．14、59．40、99．94mg·kg^-1和6．320mg·kg^-1。果实中的Cd、Pb和Zn最大品种间差异分别达4．4倍、4．2倍和1．6倍;各品种3种重金属含量ANOVA分析结果显示了品种间差异具有极显著意义。不同仁色（花仁、红仁及黑仁）长豇豆品种间的3种重金属含量在根部均有显著差异,而Zn及Cd含量在茎组织中也有显著差异;但各组在叶及果实中没有显著差异。尽管污灌区土壤Cd、Pb和Zn浓度均超出了国家土壤环境质量标准二级土壤的最高限值,但绝大多数品种的果实中所含重金属均符合国家食品卫生标准。Pb较易在果实中积累,有一个品种果实Pb浓度超过国家标准。根和茎中的3种重金属含量相互间均具有高度相关性,且果实中的Cd和Pb含量间也有显著相关,表明长豇豆对Cd、Pb和Zn的吸收和积累有协同性,这一特性使得同时低量积累重金属的长豇豆品种的筛选更为容易,特别是在可食部分同时低量积累Cd和Pb的品种。污灌区具有比对照区更高的产量,说明长豇豆能耐受农田中Cd、Pb和Zn的复合污染,因而生产者比较难以从长豇豆的中毒症状发现重金属的污染,导致在污染土壤中生产长豇豆容易受重金属污染。可见,筛选和培育低量积累重金属的长豇豆品种有利于降低人类通过食物链暴露于重金属的水平。     

Accumulation of copper and zinc from liquid manure in agricultural soils and crop plants

In Northern Italy it is a common practice to utilise slurries and other manure from intensive animal farming to fertilise agricultural soils. Due to the relatively high copper and zinc contents of these materials, this practice could lead to contamination of soils and the crops grown on them. In this study we have evaluated the extent of copper and zinc contamination of soils subjected to different levels of fertilisation with liquid manure and the copper and zinc concentrations in the edible tissues of three crops (maize, sugar beet and lucerne) grown on the same soils. There was a direct correlation between soil copper and zinc contents and the levels of application of animal wastes and copper concentrations were high enough to represent a risk, according to current European legislation. The metal contents in the edible tissues of the three crops were relatively low and variable, but showed no clear correlations with the intensity of liquid manure applications. Overall, there was no risk of contamination of the food chain, as all concentrations were well below levels considered to be toxic to animals.     

典型矿冶区周边土壤微生物功能特征及影响因素

土壤微生物对重金属污染胁迫敏感,但在实际野外环境中,土壤微生物群落生态效应通常是污染胁迫和环境因素综合作用的结果。为探究重金属污染土壤中微生物群落生态效应发生变化的主控因素,本研究以湖南省某典型矿冶区周边不同土地利用类型土壤为研究对象,以土壤碳氮循环过程主要的微生物功能指标土壤微生物生物量碳(MBC)、基础呼吸(BR)、诱导呼吸(SIR)和硝化潜势(PNR)为生态效应终点,进行采样调查分析。结果表明: 土地利用类型对MBC、BR和SIR影响均不显著;研究区土壤微生物功能的主要影响因子包括CaCl₂提取态Pb(CaCl₂-Pb)含量与土壤有机质(SOM)含量。多元回归分析结果表明,在CaCl₂-Pb含量为0.004～13.14 mg·kg^-1及SOM含量为0.24%～4.34%的条件下,土壤CaCl₂-Pb和SOM含量可以共同解释土壤中BR、SIR和PNR总变异的39.8%～58.3%;中等含量下(SOM在1.70%～2.36%,CaCl₂-Pb在0.004～12.98 mg·kg^-1),土壤CaCl₂-Pb和SOM含量与BR、SIR和PNR的变化能够建立显著的暴露-效应关系,可以作为测定终点定量评价重金属污染对微生物群落功能的生态效应。     

污染条件下VAM玉米元素积累和分布与根际重金属形态变化的关系

为了了解重金属Cu、Zn、Pb、Cd在土壤－根际－植物系统中的行为,揭示VAM植物减弱土壤中过量重金属对植物生理毒的抗性机理,采用原子吸收光谱测定Cu、Zn、Pb、Cd在污灌土壤中生长的VA菌根玉米和无菌根玉米中的积累和分布,并用连接形态分析技术分析了菌根际中Cu、Zn、Pb、Cd的形态分布和变化趋势,结果表明,Cu、Zn、Pb、Cd在菌根玉米中的积累量比非攻根中积累量分别减少10％、18％和29％,Cd积累量没有改变,生长7周后,菌根玉米是非菌根玉米生物量的1．5倍,与对照土壤相比,根际中除Cu交换态显著增加外,Zn、Pb、Cd各形态相对改变量显著大于非菌根,且菌根根际上中Cu、Zn、Pb有机结合态增加量显著大于非根际土,说明菌根际金属向稳定状态转移的程度显著大于非菌根际,同时,讨论了根际金属形态对金属有效性的影响,及其与菌根植物金属抗性机理的关系。     

模拟酸雨对污染土壤中Cd、Cu和Zn释放及其形态转化的影响

研究了模拟酸雨连续浸泡下污染红壤和黄红壤中重金属释放及形态转化．结果表明。随着模拟酸雨pH值下降,污染土壤中重金属释放强度明显增大;Cd、Zn释放量与酸雨pH值呈线性极显著负相关．Cu与酸雨pH值呈线性显著负相关．模拟酸雨作用下,污染红壤和黄红壤中Cd均以交换态为主;Cu则以有机结合态和氧化锰结合态为主;Zn在污染红壤中以残留态和交换态为主．在污染黄红壤中以残留态和有机结合态为主．土壤有机质含量和阳离子交换量对Cd、Cu、Zn的释放产生一定的影响并影响Cd、Zn的形态转化,但对Cu形态转化影响不明显,随着模拟酸雨酸度增大,污染红壤和黄红壤中重金属Cd、Cu的生物可利用态明显增多,但难解吸态Zn向生物有效态转化效应不明显．     

Determination of Cd, Cu, Pb and Zn in neoplastic kidneys and in renal tissue of fetuses, newborns and corpses

The incidence of kidney tumors in USA and Europe (in particular, Central Europe and Italy) has been dramatically increasing since the 1970s, possibly as a consequence of ongoing environmental pollution. Environmental factors have been considered responsible for at least 80% of the incidence of neoplastic diseases. To shed some light on this issue, the amounts of Cd and Pb were measured in neoplastic tissue and adjacent normal part of kidney excised for carcinoma and compared with those in renal tissues of fetuses, newborns and subjects that died of non-neoplastic diseases. Cd and Pb were determined by Inductively Coupled Plasma Atomic Emission Spectrometry and Atomic Absorption Spectrometry with Electrothermal Atomization. Metallothionein immunoperoxidase staining technique was used to localize the accumulation of Cd and Zn in the nephrons. Content of Cd and Pb in kidneys of fetuses and newborns was extremely low. However, it was significantly increased in adjacent-normal tissues of kidneys with carcinomas, and significantly higher compared to kidneys of individuals that died of non-neoplastic diseases. In tumoral tissues of the excised kidneys, Cd content was very low, while that of Pb significantly elevated. High amounts of Cd and Pb in the adjacent-normal parts of kidneys with carcinomas are suggestive of possible, individual or synergistic, effects of these pollutants on enzymatic systems, priming an oncogenic pathway. Detection of metallothioneins, primary ligands of Cd, exclusively in the cells of proximal tubuli, i.e. wherein renal carcinoma develops in over 80% of cases, strongly supports the assumption that Cd exerts a carcinogenic effect.     

Total nitrogen and pH-controlled chemical speciation,bioavailability and ecological risk from Cd,Cr, Cu,Pb and Zn in the water level-fluctuating zone sediments of the Three Gorges Reservoir

We investigated the distribution and chemical speciation of Cd, Cr, Cu, Pb and Zn in the water level-fluctuating (WLF) zone of the main stream (MS) and tributaries (ZX and MX) of the Three Gorges Reservoir. We evaluated the ecological risk and pollution level from heavy metals based on the Potential Ecological Risk Index (RI), Risk Assessment Code (RAC), and Ratio of Secondary Phase and Primary Phase (RSP). Our results indicated that the total and bio-available heavy metal contents were higher in the tributaries than in the MS. Moderate pollution from Cd and light pollution from Pb were observed both at the MS and ZX sites, whereas the MX site exhibited a pattern of heavy Cd pollution and light Cr and Pb pollution. In our study area, the results indicated that Cd exhibited a higher ecological risk than did the other heavy metals. Finally, the pH and nitrogen content of sediments may play a key role in controlling the amount of heavy metal bioavailability, further inducing a higher potential ecological risk.     

Chemical speciation of Zn in acidic soils: suitable soil extractant for assessing Zn availability to maize (Zea mays L.)

Abstract

Chemical fractions of soil Zn namely: water soluble (WS), exchangeable (EX), Pb displaceable (Pb-disp.), acid soluble (AS), Mn oxide occluded (MnOX), organically bound (OB), amorphous Fe oxide occluded (AFeOX), crystalline Fe oxide occluded (CFeOX), residual (RES) were determined in 20 surface (0–15 cm) samples of acidic soils from the provinces of Uttarakhand and Uttar Pradesh, India. The chemical fractions of soil Zn in acidic soils were found to be in the following descending order of Zn concentration: RES > CFeOX > Pb-Disp. > AFeOX > MnOX > AS > OB > EX > WS. These soil samples were also extracted by: DTPA (pH 7.3), DTPA (pH 5.3), AB-DTPA (pH 7.6), Mehlich 3 (pH 2.0), Modified Olsen, 0.01 N CaCl₂, 1 M MgCl ₂ and ion exchange resins. Chemical fractions and the soil extractable content of Zn estimated by different soil extractants were significantly correlated with some general soil properties. Maize (cv. Pragati) plants were grown in these soils for 35 days after emergence and Zn uptake by plants was compared with the amount of Zn extracted by different soil extractants and chemical fractions of Zn. Among chemical fractions of soil Zn, Pb-displaceable and acid soluble chemical fractions of soil Zn showed a significant and positive correlation with Zn uptake by maize. Path coefficient analysis also revealed that the acid soluble Zn fraction showed the highest positive and direct effect on Zn uptake (P=0.960). Among different multinutrient soil extractants evaluated for their suitability to assess Zn availability in acidic soils, DTPA (pH=5.3) was most suitable soil extractant, as the quantity of soil Zn extracted by this extractant showed a significant and positive correlation with the dry matter yield, Zn concentration and uptake by maize plants.     

Vertical and Horizontal Distributions of Zn,Cd, Pb,Cu, and Hg in Uncultivated Soil in the Vicinity of a Zinc Smelter at Odda,Norway

In the present work the extent and variation of Zn, Cd, Pb, Cu, and Hg loading in undisturbed surface soil (0–5 cm) and the vertical transport of the metals in soil profiles are studied in the vicinity of a zinc smelter in Norway. Three major controlling factors on the metal concentrations in soil have been assessed: 1) distance from the anthropogenic point source; 2) organic matter content (O.M.); and 3) the prevailing wind directions. Moreover metal distributions in proximal soil profiles in 1972 and 2003 are compared. Current concentrations of Zn, Cd, Pb, Cu, and Hg in surface soil reach 14000, 60, 980, 430, and 7.0 mg·kg ^{? 1} , respectively, near the smelter and decrease regularly with distance in the northerly direction according to the regression model (y = ax^{? b} ). The Zn concentrations are significantly different from the background range up to 30 km from the smelter, whereas the other metals approach background at only 10 km distance. Subsurface concentration peaks of Pb, Cu, and Hg are found at greater depth in soil profiles than peaks of Zn and Cd. Levels of Zn, Cd, and Pb in surface soil seem to have decreased from 1972 to 2003, whereas for Cu the levels appear not to be significantly different.     

Effects of planting patterns on heavy metals (Cd,As) in soils following mangrove wetlands restoration

Abstract

To understand how planting patterns influence As and Cd in soils, the pollution grade release risk and fractions of As and Cd in soils from Jinjiang Estuary wetland were investigated. The geoaccumulation index (I_geo) and risk assessment code (RAC) were used to identify pollution grades and reveal the potential ecological risk of trace metals, respectively. The results showed that the ratios of the acid soluble fraction of Cd in the mangrove area (～65%) were larger than that of the control group (～31%). The residual fraction of As in the mangrove area (～74%) was also larger than that of the control group (～66%). Therefore, the planting of vegetation increased the mobility of Cd and decreased the mobility of As. Variance analysis showed that the total concentrations and fraction of As and Cd significantly differed among various vegetation types and planting densities. Thus, planting patterns might influence the transformation of trace metal fractions in soil, influencing the total concentrations of As and Cd. Furthermore, mangrove reforestation improved the pollution levels of As and Cd and increased the potential release risk of Cd. The study advances current knowledge on the importance of restoring wetland vegetation, providing suggestions on feasible planting patterns.     

Zn buffering capacity and Zn accumulation in Swiss chard for some sludge-amended soils

Zinc sorption by soils can greatly affect its availability to plants. This study was conducted to determine the relationship between the Zn sorption capacity and plant Zn accumulation in five sludge-amended soils using Swiss chard (Beta vulgaris L.) as an indicator plant. Zinc sorption as a function of Zn concentration and pH was determined for the soils which received no sludge amendment; also DTPA (diethylenetriaminepentaacetic acid) extractable Zn was determined in all soils. Whereas the responses of DTPA-Zn and plant Zn to pH and the quantities of Zn sorbed were similar, the logarithm of DTPA-Zn accounted for only 82% of the variability in the logarithm of Zn accumulation by the plants. The variability was better explained when pH was included with DTPA-Zn in stepwise multiple regressions. The Zn buffering capacity, defined as the ratio of the change in quantity of Zn sorbed ( Zn_s) to the change in Zn solution concentration (Zn₁) (or Zn_s/Zn₁), and the estimated quantity of Zn sorbed were used as a basis to measure Zn intensity. Zinc intensity, which reflects Zn solution concentration, was the predominant factor controlling Zn accumulation by Swiss chard, judging from the good fit of the values of both parameters to the Michaelis-Menten equation. The maximum Zn accumulation was approximately 9 mmol kg^–1.Scientific paper no. 8901-29, Department of Agronomy and Soils, College of Agriculture and Home Economics Research Center. Washington State University, Pullman, WA 99164, USA.Scientific paper no. 8901-29, Department of Agronomy and Soils, College of Agriculture and Home Economics Research Center. Washington State University, Pullman, WA 99164, USA.     

Effects of mine effluent on uptake of Co,Ni, Cu,As, Zn,Cd, Cr and Pb by aquatic macrophytes

Concentrations of Ni, Co, Cu, Pb, Zn, Cd, Cr and As were determined in aquatic sediments, water and macrophytes collected from a fluvial system, contaminated by mine effluents. Myriophyllum verticillatum collected in May below the trace element point source accumulated 169 µg/g of Ni, 860 µg/g of Co, 37 µg/g of Cu, 31 µg/g of Pb, 92 µg/g of Zn, 6.9 µg/g of Cr and 1,200 µg/g of As (concentrations in dry weight). The aquatic macrophytes Nymphaea odoratae and Pontederia cordata accumulated the investigated trace elements to a much lesser extent. The concentrations of trace elements in Myriophyllum verticillatum decreased from May to August. Correlations were found between the concentrations of total Ni, Co and Cu in the bottom sediment and in the submerged macrophytes. However, there was no correlation between the amounts of these trace elements extractable by 0.5 N HCl from the sediments and the concentrations in the macrophytes.     

Competitive adsorption of Pb, Cd and Zn ions onto Eichhornia crassipes in binary and ternary systems

A batch sorption technique was used to study the biosorption of Pb²⁺, Cd²⁺ and Zn²⁺ ions onto the vastly abundant water hyacinth weed, Eichhornia crassipes biomass in binary and ternary systems at a temperature of 30 °C and pH 4.84. Mutual interference effects were probed using equilibrium adsorption capacity ratios, , where the prime indicates the presence of one or two other metal ions. The combined action of the metals was found to be antagonistic, and the metal sorption followed the order Pb²⁺  Cd²⁺  Zn²⁺. The behaviour of competitive biosorption for Pb–Cd and Pb–Zn combinations were successfully described by the Langmuir Competitive Model (CLM), whilst the model showed poor fitting to the Cd–Zn data. In conclusion, Pb²⁺ ions could still be effectively removed from aqueous solution in the presence of both Cd²⁺ and Zn²⁺ ions, but removal of the Cd²⁺ and Zn²⁺ ions would be suppressed in the presence of Pb²⁺.     

Effects of Copper,Nickel, and Sulfate from the Smelters at Sudbury,Ontario (Canada) on Microbial Communities in Lakes

Analysis of water and sediments from deep and shallow environments in lakes located 6–154 km east or southeast of the smelters at Sudbury, Ontario (Canada) revealed variable, interactive effects of copper, nickel, and sulfate from smelter fallout on lacustrine microfloras. Metal species in sediments were differentiated by sequential extractions, and the nature, abundances, and activities of microbial populations were represented by chlorophyll-a in water and by CO₂ production, fatty acids, phospholipids, dehydrogenase, alkaline phosphatase, and spectral properties of humic matter in sediments. Smelter fallout declined logarithmically with distance from the smelters, and its effects on microfloras depended on the type of microorganism or microbial process and on environmental factors and the abundances of metal species and detoxifying agents. Extractable copper and nickel had toxic effects, which were not attributable solely to the exchangeable fractions, but in certain cases nickel counteracted copper toxicity. Sedimentary sulfide as a whole or sulfide produced by bacterial sulfate reduction, or low oxidation–reduction potential regardless of sulfide concentration, ameliorated metal toxicity by making the metals less bioavailable; and toxicity showed a “quantum jump” when detoxifying agents fell below certain critical concentrations, implying the existence of threshold levels of bioavailable metals above which toxicity increased abruptly. In some cases metal toxicity was lowest in the lakes closest to the smelters (because sulfate concentrations were highest) as well as in the lakes furthest away, and was highest at intermediate distances. The results also suggest that nickel pollution led to ecological succession whereby nickel-tolerant microbial populations replaced nickel-sensitive ones.     

The distribution of cadmium,copper, lead,zinc and calcium in the tissues of the earthworm Lumbricus rubellus sampled from one uncontaminated and four polluted soils

Summary The tissue distribution of Cu, Cd, Pb, Zn, and Ca in the earthworm Lumbricus rubellus living in non-polluted and heavy-metal polluted soils was investigated. Cd, Pb and Zn were primarily accumulated within the posterior alimentary canal. As the whole-worm Pb burden increased, the proportion of the metal accumulated within this tissue fraction increased. A similar pattern was found for Zn. By contrast, 70%–76% of the Cd burden was found in the posterior alimentary canal, irrespective of the whole-worm Cd content. The accumulation of Cd, Pb and Zn primarily in the posterior alimentary canal prevents dissemination of large concentrations of these metals into other earthworm tissues, and may thus represent a dextoxification strategy based on accumulative immobilisation. Cu was distributed fairly evenly in the tissue fractions investigated. There was no evidence of sequestration of this metal. The apparent lack of a detoxification strategy may contribute to the well-known susceptibility of earthworms to low environmental Cu concentrations. Indeed, earthworms from the site of highest soil Cu (Ecton) were markedly smaller than those from the other sites sampled. The highest Ca concentrations were found in the anterior alimentary canal, and were related to calciferous gland activity. A large proportion of Ca was also stored as a physiologically available pool in the posterior alimentary canal. Despite huge variations in soil Ca concentrations, the body wall Ca levels were fairly similar in L. rubellus from all the study sites. Thus, L. rubellus may become physiologically adapted to soils of exceptionally low Ca concentration. The observations are discussed in the context of the merits of analysing specific tissues, rather than whole organisms, for the purpose of monitoring metal bioaccumulation.     

一株能分解纤维素放线茵的固态发酵研究

对一株从食草动物的粪便中分离出来的放线菌菌株（XW5）,以秸杆粉和麸皮为底物,进行固态发酵,并提取纤丝至望粗酶。采用DNS法,进行酶活测定,研究发现该菌株的固态发酵酶活为4—7u／mg。并对酶活的影响因子、pU、温度以及金属离子等的影响进行了探讨,同时发现该酶为碱性纤维素酶。