“不着一字,尽得风流”——论约翰·高尔斯华绥《黑花》之“空白”美

意境"空白"是艺术中"美"的本质的一种体现,它有着丰厚的理论渊源。所谓"空白",就是言外之意、象外之象、韵外之致,给读者再创造和想象的审美空间。高尔斯华绥《黑花》中内容描写和新颖的写作方式均与"空白"意境相切合。

Infection of the Anther-smut Microbotryum violaceum in Populations of Silene dioica: Variation in Floral Morphology, Patterns of Spore Deposition and Pathogen-Pollinator Mediated Selection

The anther-smut Microbotryum violaceum ( Brandenburger and Schvinn) G. Deml. and Oberw.) causes a systematic infection of its host Silene dioica ( L.) Clairv., resulting in sterility and production of teliospores (dispersal propagules) in flowers. These spores are transmitted to healthy plants mainly by flower visitors. The behavioral responses of flower visitors to a variation in floral characters are not only likely to affect rates of pollen export/import, but also the rate of spore deposition and probability of disease. In a transplantation experiment, using plants from four different populations, we tested for correlation between variation in female floral morphology and patterns of spore and pollen deposition, and a resulting risk of disease. The source populations in this experiment were located on four islands in Skeppsvik archipelago in northern Sweden, and represented a gradient of disease incidence from completely healthy ( Island 1), low incidence ( Island 2) to high incidences ( Islands 3 and 4) of disease. Fifty plants from each population were transplanted to the center, of the population on Island 4. There were significant differences among the transplants in floral characters, i.e. corolla size, style length and ovule number. Plants from the non-diseased population had larger flowers and longer styles than plants from the highly diseased populations. Numbers of pollen grains and spores deposited on flowers were strongly and positively correlated. We found that plants originating from the non-diseased population captured approximately 4 times more pollen and 9 times more spores, per flower than die individuals from the resident population (Island 4, population 4). The incidences of disease among plants, from the four populations differed significantly, and was 37%, 20%, 18% and 0 for populations 1, 2, 3 and 4 respectively. In a survey of ten populations we found a significant negative correlation between the mean style length ( positively correlated with corolla size and ovule number) among healthy plants and incidence of disease in these populations. The potentiality for pathogen-pollinator mediated selection oil floral characters; and consequences for gone flow between populations of Silene dioica are discussed.

Comparison of Morphological Microstructure of Vitrified and Normal Shoots of Aronia melanocarpa Elloit

The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-tearing method. The results showed the palisade tissue of Aronia melanocarpa El oit consists of 2-3 lay-ers of cells. The stomas on lower epidermis cave in, and are smal and dense. There are abundant vessels and sieve tubes in stems. ln contrast, the main veins of vitrified shoots are unobvious, messy and irregular. The boundary between pal-isade tissue and spongy tissue is not obvious. The stomas open circularly and bigly. The stems are swel ing and thick, but the pith parenchyma cells are broken.

Effect of Cowshed Design and Cooling Strategy on Welfare and Productivity of Dairy Cows

Nine cowsheds were used, the differences between each cowshed are orientation （east-west or north-south）, cooling （with or without）, and height （3 m, 5 m or 8 m height）. Dry-bulb temperature, relative humidity, dew point, shaded area, air velocity, and maximum temperature were measured beneath each shed. The temperature-humidity index （THI） and the shading efficiency were calculated for each cowshed. The trials were conducted using 180 lactating Holstein Friesian cows; twenty cows housed beneath each shade structure. Measurements performed on cows were respiration rate, skin temperature, and rectal temperature; moreover, the milk produced by each cow was recorded, and the feed intake. High air velocities were recorded under high shade structures which enhance the aeration; consequently, maximum temperatures, and THI recorded beneath high sheds were less than those recorded beneath low sheds; also, skin temperatures, and respiration rates for cows housed under high sheds were less than those measured for animals housed under low sheds（differences were found to be significant）. Thereby, increasing shed height enhances dairy cows＇ microclimate under Egyptian conditions （hot climate）; consequently, the milk production increases. The best orientation is the east-west orientation, which is preferable for hot climates. The exploitation of cooling has significant effect on microclimate, cooling enhances the ambient environment and provides comfortable zone for dairy cows within which cows reach high production levels.

Histological Investigation of Pelvic Symphysis in Holstein-Friesian Cattle

Knowledge of the changes in cattle pelvic symphysis during gestation and obstetrics gives valuable information about the age of optimal primary calving of cows. The aim of the study was to investigate the histological changes of pelvic symphysis in Estonian Holstein-Frisian＇s （EHF） of different ages. Eight EHF cows up to five years of their age were divided into three age groups： calved, in-calved and after calved bovines. Material for histological and histochemical investigation was taken from four places： （1） cranial part ofpubic bone; （2） pubo-ischiadic junction; （3） symphyseal eminence; （4） body of the interischiadic bone. In all study-groups, the cranial part of pubic bone consisted of cartilage. In pubo-ischiadic junction of calves connective tissue proper, fibrous and hyaline cartilage were noted. In in-calved cattle with gestation of 4-5 months and in after calved cattle group hyaline cartilage and bone tissue were noted, however in in-calved cattle with gestation of 7.5 months fibrous cartilage and connective tissue proper prevalated. In sympyseal eminence of calves connective cartilage osseous tissue was present. The region of interischiadic tissue proper and cartilage were noted; in other groups besides bone of calves consisted of connective tissue proper and fibrous cartilage, meanwhile in in-calved and after calved EHF＇s in the region hyaline cartilage and osseous tissue prevalated. These preliminary results demonstrate that the main changes in the pelvic symphysis histology, retardation of ossification, of EHF kines occur during the second-half of gestation in the pubo-ischiadic junction.

Dynamics of settling participate matter during typhoon Muifa in Heini Bay,China

Settling particulate matter(SPM) is widely used to describe the sedimentary environment.We have investigated here the SPM collected with a time-series sediment trap in the Heini Bay,Weihai,Shandong Peninsula,China,during the super typhoon Muifa(August 2011,maximum wind speed 55 m/s).Meteorological and hydrological parameters were measured for 18 days.By analyzing the particle flux,grain size,and loss-on-ignition(organic matter content) of SPM we found dramatic changes in these parameters,induced by typhoon Muifa for about 6 days.With the arrival of typhoon,the daily SPM fluxes increased sharply to the maximum at 76.4 g/(m^2·d) on the first day and this increase is about 9 times of the normal value,and after 6 days the SPM decreased to the normal value gradually.Other parameters,such as grain size of SPM and organic matter also experienced similar changes.Using these SPM parameters,we divided the settling progress by cluster analysis into three phases:strong(for 3 days),weak(for 3 days),and zero typhoon impact.

The Effect of Farm Location on Physiological Conditions and Productivity of Friesian-Holstein Crossbreed Cows

Farm location is an important factor in dairy farms, as it is closely associated with temperature and humidity that are crucial factors of influencing the physiological conditions and productivity of cows especially during the lactation period. The purpose of this study was to determine the effect of farm location on the physiological conditions and productivity of cows. The study was involved in 18 lactating Friesian-Holstein crossbreed cows in three farmer groups, i.e., Nangkasawit, Plalangan and Sumurejo. Temperature and humidity of the environment, rainfall and physiological conditions of cows （respiration rate, pulse, rectal temperature, total erythrocytes, hemoglobin and hematocrit） were observed. No influence （P 〉 0.05） of farm location on the parameters was observed, except for milk production （P 〈 0.05）. In conclusion, farm location had no impact on the physiological conditions of Friesian-Holstein crossbreed cows in the district Gunungpati Semarang, Central Java, Indonesia.

Comparison of Two Different Protocols for Induction of Parturition in Heifers with or without Estradiol Benzoate

Objectives of this study were to investigate the efficacy of dexamethasone in combination with estradiol benzoate in controlled induction of parturition in heifers, especially in the subjects of retained fetal membranes and dystocia caused by fetal oversize. A total number of 100 Holstein-Friesian heifers aged 24-25 months, mean weight 450 kg and body condition score of 3-4 from a dairy herd located in the suburb of Tabriz with similar nutrition and management systems were allocated at random into two groups. Group A （Control, n = 50） heifers, after passing the minimum 270 d of pregnancy were injected with 30 mg dexamethasone IM. Group B （Treatment, n = 50） heifers with the same period of pregnancy received 30 mg dexamethasone plus 20 mg estradiol benzoate IM on the same days of pregnancy. The overall durations of initial treatments to induction of parturition were （41.50 ~ 2.65） h in group A and （37.50 ：i： 1.27） h in group B. In group A, more dystocia cases were observed than in group B. After parturition, group A showed a higher percentage of retention of fetal membranes as well as the calf mortality and dystocia compared to group B. The differences between two groups were statistically significant （P 〈 0.05）. In conclusion, our results indicate that induction of parturition by estradiol benzoate and dexamethasone together will be more effective than dexamethasone alone because of the less retention of fetal membranes, easy calving and shorter time from induction to parturition.

Effect of Organic vs. Inorganic Selenium Supplementation on Expression of Selected Defensin Genes in Somatic Milk Cells of Dairy Cows

The aim of the study was to evaluate the impact of organic selenium supplementation （selenium yeast） vs. inorganic selenium （selenium selenite） on the expression of selected defensin genes in milk somatic cells （MSC） of dairy cows. Sixteen Polish Holstein-Friesian cows in second parity, with similar milk yield and milk composition were randomly divided into two equal groups. At the beginning of experiment, the animals were in the middle of their lactation curve （150, standard deviation （SD） = 26 d） and this experiment lasted 90 d. The basic diet, for both groups, consisted of corn silage, wilted grass silage and concentrates. The diet of control group was supplemented with commercial mineral and vitamin mixture with inorganic selenium and the for the experimental group daily selenium need was covered by the addition of Se-yeast （6 mg Se/cow/d）. Milk samples were collected three times during experiment （before experiment; on day 55; after the end the experiment）. Total RNA was isolated from milk somatic cells and the levels of transcripts of bovine β1-defensin （DEFB1）, β4-defensin （BNBD4）, β5-defensin （BNBDS）, β10-defensin （BNBD10） and lingual antimicrobial peptide （LAP） were measured with real time PCR, using glyceraldehyde 3-phosphate dehydrogenase （GAPDH） as a reference gene. The expressions of almost all studied genes were influenced by environmental conditions （very low and negative temperature）. However, BNBD4 （P 〈 0.05） and LAP （P ≤ 0.001 ） genes were influenced by selenium supplementation but in opposite ways, depending on the form of Se. These findings support that selenium is an important factor affecting the mRNA level in MSC, but the effect of the form of selenium might depend on genes.

Geology and fluid inclusion characteristics of Qilishan gold deposit in Zhaoyuan of Shandong,China

The Qilishan gold deposit is located in the southern Zhaolai gold ore belt in the northwestern Jiaodong region.A total of seven gold ore bodies have been found in the mining area.Linglong gneissic biotite granite and the NE trending Lingbei fracture control the output and distribution of the gold deposit.The ore bodies with veined or irregular shape occur in the structural alteration zone.The ore bodies of different sizes are NE trending and SE dipping.The constituent minerals of the ores mainly include pyrite,chalcopyrite,native gold,electrum,argentite,matildite,hematite,quartz and calcite.The ores are characterized by metasomatic dissolution structure,as well as veined and brecciated structures.The ore-forming process is divided into four stages,namely quartz-,pyrite-,polymetallic-and carbonate stages.Study on fluid inclusion shows that the deposit is composed of gas-liquid two-phase inclusions （Ⅰ） and three-phase inclusions containing CO2 （Ⅱ）,and that the former dominates.The homogenization temperature is 259.6℃-373.7℃ ; the salinity of three-phase inclusions containing CO2is 5.77%-9.84% （NaCl） ; the salinity of gas-liquid two-phase inclusions is 6.58%-8.54% （NaCl） ; and the estimated ore-forming pressure is 55.2-82.2 MPa.According to the nonlinear relationship between the depth and pressure of the fluid in the fracture zone,the ore-forming depth of the Qilishan gold deposit is calculated as 5.95-7.14 km.It is preliminarily determined that the deposit is a mesophilic and hypothermal gold deposit.

The Applicability of Soil＇s Fertilizers in Increasing of Production Effects in Lolium Perenne and Lolium Multiflorum Cultivation

The aim of the study was to determine the effect of soil fertilizers, used on the background of NPK fertilization on the productivity of Lolium perenne and Lolium multiflorum in different time of harvest. In 2012-2013 the following species and varieties of forage grasses： Lolium perenne and Lolium multiflorum were cultivated. It was the fallowing experimental subjects： K-control （without fertilization and fertilizer）, NPK （N-150 kg hal as a 34% ammonium nitrate, P-80 kg P2O5 ha-1, K-120 kg K20 ha-1）, UG-UGmax bio-preparation, EU-Eco bio-preparation （fertilizer）, HA-Humus Active as bio-preparation.

Adaptability of Alfalfa and Ryegrass to New Reclamation Materials

This paper discussed the adaptability of the alfalfa and ryegrass to the new artificial soil that was composed of fly ash and furfural residue. The potted experiments were taken to compare the growth conditions, yields, and qualities of both grasses. Some pots were covered with wheat stalks and others without. The medium Fluvo-aquic soil was taken as control. The results indicated that the growth of two grasses in the mixture were inferior to their growth in the control in initial period. With the leaching of rain and irrigation, the two grasses improved gradually. The alfalfa and ryegrass both could grow in the new mixture, and the ryegrass would be better to plant in no covered material and the alfalfa in covered. This will be a new way to reclaim subsided land and to imorove the environment in mining area.

Firework Induced Large Increase in Trace Gases and Black Carbon at Dibrugarh, India

Religious, occasional and annual fire work festivals worldwide are found to introduce high concentrations of pollutant gases and particulate matter into the atmosphere. These in turn alters the air quality of a region in the short and long time scales and affect human health adversely. The effect of fireworks on short-term variation in air quality of an urban location Dibrugarh, set amidst the rural environment of north-east India, was assessed from the ambient concentrations of 03, SO2, NOx, CO and BC （black carbon） during the Diwali festival during Nov. 13-14, 2012. The firework activity in general peaks during evening to midnight hours. Substantial increase in concentrations of O3, SO2, NOx, CO and BC was observed during the peak hours of firework activity （16：00 h to 22：00 h） in the Day 1 and Day 2 of the Diwali festival. However, the increase in concentrations from the background level was found to be highest on the post-Diwali day due to their accumulation in the atmosphere. The firework activity has not affected the regular diurnal pattern of the measured species during this episode.

Songjianghe biotite monzonitic granite zircon U-Pb geochronology and geochemical significance

The authors studied geochronology and geochemical data of the Songjianghe biotite monzogranite in the southern Zhangguangcai Range in order to determine its formation age,magma source,and tectonic environment. The results indicate that the Songjianghe biotite monzogranite was formed in the Middle Jurassic with an age of 168. 2 ± 2. 0 Ma( MSWD = 0. 93). The monzogranite was characterized by high alkali and low Ca O and Mg O,belonging to high-potassium calc-alkaline,metaluminous I-type granite. The rock is enriched in large ion lithophile elements such as Rb,Ba,and K and strongly depleted high field strength elements such as P,Ti,Nb,and Ta. It is concluded that the Songjianghe biotite monzogranite was derived from partial melting of amphibolite facies metamorphism mafic lower-crust and its formation was controlled by the Pacific Plate subduction.

Characterization of proanthocyanin-related leucoanthocyanidin reductase and anthocyanidin reductase genes in Lycium ruthenicum Murr.

Proanthocyanidins （PAs） are a set of important phytochemical compounds in Lycium ruthenicum Murr. However, PAbiosynthesis in L. ruthenicum remains unclear. In this study, leucoanthocyanidin reductase （LAR） and anthocyanidin reductases（ANR） involved in PA biosynthesis were retrieved from L. ruthenicum EST database. Polymerase chain reaction （PCR） resultsconfirmed that LrLAR and LrANR encoded a protein composed of 333 and 338 amino acids, respectively. Phylogenetic analysisshowed that LrLAR and LrANR were clustered with known LAR and ANR proteins of other plants, respectively. Quantitativereverse-transcription PCR （qRT-PCR） results indicated that both genes expressed in a sharp increase manner from unripe stage tocolor break stage and were down-regulated increasingly hereafter, and that both expression levels are extremely low in youngleaves, mature leaves, stems, and roots compared with fruits. Phytochemical assay revealed that the content of total PA in fruitwas higher than that in young leaves, mature leaves, stems, and roots, and that the total PA level was increased sharply andthen relatively stable hereafter during fruit ripening. Our results lay a foundation for uncovering the PA biosynthesis and furtherengineering manipulation in L. ruthenicum.

Diversity of Mesozoic tin-bearing granites in the Nanling and adjacent regions,South China:Distinctive mineralogical patterns

The Nanling and adjacent regions of South China host a series of tin deposits related to Mesozoic granites with diverse petrological characteristics. The rocks are amphibole-bearing biotite granites, or （topaz-） albite-lepidolite （zinnwaldite） granites, and geochemically correspond to mealuminous and peraluminous types, respectively. Mineralogical studies demonstrate highly distinctive and critical patterns for each type of granites. In mealuminous tin granites amphibole, biotite and perthite are the typical rock-forming mineral association; titanite and magnetite are typical accessory minerals, indicating highjO2 magmatic conditions; cassiterite, biotite and titanite are the principal Sn-bearing minerals; and pure cassiterite has low trace-element contents. However, in peraluminous tin granites zirmwaldite-lepidolite, K-feldspar and albite are typical rock-forming minerals; topaz is a common accessory phase, indicative of high peraluminity of this type of granites; cassiterite is present as a uniquely important tin mineral, typically rich in Nb and Ta. Mineralogical distinction between the two types of tin granites is largely controlled by redox state, volatile content and differentiation of magmatic melts. In oxidized metaluminous granitic melts, Sn4＋ is readily concentrated in Ti-bearing rock-forming and accessory minerals. Such Sn-bearing minerals are typical of oxidized tin granites, and are enriched in granites at the late fractionation stage. In relatively reduced peraluminous granitic melts, Sn2＋ is not readily incorporated into rock-forming and accessory minerals, except for cassiterite at fractionation stage of granite magma, which serves as an indicator of tin mineralization associated with this type of granites. The nature of magma and the geochemical behavior of tin in the two types of granites thus result in the formation of different types of tin deposits. Metaluminous granites host disseminated tin mineralization, and are locally related to deposits of the chlorite quartz-vein, greisen, and skarn types. Greisen, skarn, and quartz-vein tin deposits can occur related to peraluminous granites, but disseminated mineralization of cassiterite is more typical.

Petrogenesis of early Yanshanian highly evolved granites in the Longyuanba area,southern Jiangxi Province:Evidence from zircon U-Pb dating,Hf-O isotope and whole-rock geochemistry

Early Yanshanian(Jurassic) granitoids are widespread in the Nanling Range,South China.Whereas large granitic batholiths commonly crop out in the center of the Nanling Range(corresponding geographically to the central and northern parts of Guangdong Province),many small stocks occur in the southern part of Jiangxi Province.Most of the small stocks are associated closely with economically significant rare-metal deposits(W,Sn,Nb,Ta).Here we report the results for biotite granites and two-mica granites from three Yanshanian stocks of the Longyuanba complex.LA-ICPMS U-Pb dating of zircon yields an age of 156.1±2.1 Ma for Xiaomubei biotite granite,and U-Pb zircon dating using SIMS yields an age of 156.7±1.2 Ma for Longyuanba-Chengjiang biotite granite and 156.4±1.3 Ma for Jiangtoudong two-mica granite.Biotite granites are silica-rich(SiO 2 =70%-79%),potassic(K 2 O/Na 2 O>1.9),and peraluminous(ASI=1.05-1.33).Associated samples are invariably enriched in Rb,Th,Pb and LREE,yet depleted in Ba,Nb,Sr,P and Ti,and their REE pattern shows a large fractionation between LREE and HREE((La/Yb) N =10.7-13.5) and a pronounced Eu negative anomaly(δEu=0.28-0.41).Two-mica granite samples are also silica-rich(SiO 2 =75%-79%),potassic(K 2 O/Na 2 O>1.2),and peraluminous(ASI=1.09-1.17).However,in contrast to the biotite granites,they are more enriched in Rb,Th,Pb and extremely depleted in Ba,Nb,Sr,P and Ti,and exhibit nearly flat((La/Yb) N =0.75-1.08) chondrite-normalized REE patterns characterized by strong Eu depletion(δEu=0.02-0.04) and clear tetrad effect(TE 1.3 =1.10-1.14).Biotite granites and two-mica granties have comparable Nd isotopic signatures,and their εNd(t) are concentrated in the 13.0 to 9.6 and 11.5 to 7.7 respectively.Their zircon Hf-O isotopes of both also show similarity(biotite granites:εHf(t)= 10.8-7.9,δ 18 O=7.98‰-8.89‰ and εHf(t)= 13.8 to 9.1,δ 18 O=8.31‰-10.08‰;two-mica granites:εHf(t)= 11.3 to 8.0,δ 18 O=7.91‰-9.77‰).The results show that both biotite and two-mica granites were derived mainly from sedimentary source rocks with a minor contribution from mantle-derived materials.In spite of some S-type characteristics,the biotite granites were formed by fractional crystallization of I-type magma and assimilation of peraluminous sedimentary rocks during their ascent to the surface.Therefore,they belong to highly fractionated I-type granites.Two-mica granites exhibit a tetrad effect in their REE patterns,but share the same isotopic features with the biotite granites,suggesting that they are highly fractionated I-type granites as well.Their Lanthanide tetrad effects may be attributed to the hydrothermal alteration by magmatic fluids that have suffered degassing at late stages.Granitic magmas undergoing fractional crystallization and wall-rock assilimation can generate highly evolved granites with no REE tetrad effect in the uni-phase system.However,in the late-stage of magmatic evolution in the multi-phase system(i.e.,magmatic-hydrothermal system),these magmas also can lead to the highly evolved granites exhibiting mew-shaped REE pattern characterized by tetrad effect as the consequence of melt-fluid and fluid-vapor fractionation,and the resultant autometasomatism.We thus suggest that the REE pattern exhibiting tetrad effect feature is an important indicator of rare metal mineralization in the early Yanshanian time in southern China,implying the metamorphism of the ore fluid.

VdPKS1 is required for melanin formation and virulence in a cotton wilt pathogen Verticillium dahliae

Verticillium dahliae is a soil-borne phytopathogenic fungus that causes vascular wilt disease in a broad range of hosts. This pathogen survives for many years in soil in the form ofmelanized microsclerotia. To investigate the melanin synthesis in V.. dahliae, we identified a polyketide synthase gene in V. dahliae, namely VdPKS1. PKS1 is known to involve in the dihydroxynaphthalene melanin synthesis pathway in many fungi. We found that VdPKS1 was required for melanin formation but not for microsclerotial production in E dahliae. The VdPKS1 gene-disruption mutant （vdpksl） formed melanin-deficient albino microsclerotia, which did not affect the fungal colonization in host tissues but significantly reduced the disease severity. Gene transcription analysis in the wild-type and the vdpks1 strains suggested that VdPKS1 gene-disruption influenced the expression of a series of genes involved in ethylene biosynthesis, microsclerotial formation and pathogenesis. Our results suggest that the VdPKS1-mediated melanin synthesis is important for virulence and developmental traits of E dahliae.

A preliminary study of rare-metal mineralization in the Himalayan leucogranite belts, South Tibet

The Himalayan leucogranite occurs as two extensive(>1000 km) E-W trending belts on the Tibetan Plateau with the unique features. The leucogranite comprised biotite granite, two-mica/muscovite granite, tourmaline granite and garnet granite, which have been identified in previous studies, as well as albite granite and granitic pegmatite that were identified in this investigation. Fifteen leucogranite plutons were studied and 12 were found to contain rare-metal bearing minerals such as beryl(the representative of Be mineralization), columbite-group minerals, tapiolite, pyrochlore-microlite, fergusonite, Nb-Ta rutile(the representative of Nb-Ta mineralization), and cassiterite(the representative of Sn mineralization) mainly based on the field trip,microscope observation and microprobe analysis. The preliminary result shows that the Himalayan leucogranite is commonly related to the rare-metal mineralization and warrants future investigation. Further exploration and intensive research work is important in determining the rare-metal resource potential of this area.

Effects of Earthworms and Ryegrass on the Removal of Fluoranthene from Soil

Earthworms can promote the bioremediation of contaminated soils through enhancing plant growth and microorganism development. The individual and combined effects of earthworms and ryegrass （Lolium multifloram Lain.） on the removM of fiuoranthene from a sandy-loam alluvial soil were investigated in a 70-d microcosm experiment. The experiment was set up in a complete factorial design with treatments in four replicates： without earthworms or ryegrass （control, CK）, with earthworms only （E）, with ryegrass only （P）, and with both earthworms and ryegrass （EP）. The residual fluoranthene, microbial biomass C, and polyphenol oxidase activity in the soil changed significantly （P 〈 0.01） with time. In general, the residual concentration of fluoranthene in the soil decreased sharply from 71.8-88.7 to 31.7-37.4 mg kg-1 in 14 d, and then decreased gradually to 19.7-30.5 mg kg-1 on the 70th d. The flu- oranthene concentration left in the soil was the least with both earthworms and ryegrass, compared to the other treatments at the end of the experiment. Half-life times of fluoranthene in the E, P, and EP treatments were 17.8%-36.3% smaller than that of CK. More fluoranthene was absorbed by earthworms than ryegrass. However, the total amounts of fluoranthene accumulated in both the ryegrass and earthworms were small, only accounting for 0.01%-1.20% of the lost fluoranthene. Therefore, we assumed that microbial degradation would play a dominant functional role in fluoranthene removal from soil. We found that earthworms significantly increased microbial biomass C and polyphenol oxidase activity （P 〈 0.01） in the presence of ryegrass at the end of the experiment. Furthermore, microbial biomass C and polyphenol oxidase activity were significantly （P 〈 0.05） and negatively related to the residual fluoranthene concentration. This implied that earthworms might promote the removal of fluoranthene from soil via stimulating microbial biomass C and polyphenol oxidase activity.