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Table of Content

Volume 27 Issue 5
25 September 2011
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Effects of Non-Tillage on N2O and CO2 Emissions From Sandy Loam Soil in the North China Plian
CAI Yan-Jiang, DING Wei-Xin, ZHU An-Ning, ZHANG Jia-Bao
2011, 27(5):  1-6. 
Abstract ( 1277 )   PDF (920KB) ( 1879 )  
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To investigate effects of non-tillage on N2O and CO2 emmissions in the North China Plain,a field experiment was conducted to measure N2O and CO2 emiisions from soil under conventional tillage and soil that had just assumed non-till-age practice,using close chamber technique and gas chromatography during the maize growing season.Cumulative N2O emission from the non-tillage soil was 0.31 kg·hm-2,just slightly higher than from the tilled soil,being 0.27kg·hm-2.In contrast,non-tillage significantly increased soil CO2 emission by 41.6% compared to tillage(1333kg·hm-2).N2O emission peaks appeared after irrigation,heavy rainfall or consecutive cloudy days.N2O emission peaks in the non-tillage treatment ranged from 28.1 to 38.4 μg·m-2·h-1,which were greater than those in the tillage treament (18.6-25.7 μg·m-2·h-1).N2O and CO2 fluxes in the two tillage systems displayed a significant exponential relationship with soil temperature,and the seasonal variation of N2O and CO2 fluxes could be better explained by soil temperature in tilled soil than in non-tilled soil.
Chemical Speciation and Availabilith of Mn and Zn to Tea in Soils of the Fenghuangshan Tea Belt,East Guangdong
LI Zhang-Wei, ZHANG Min, XU Gui-Song
2011, 27(5):  7-12. 
Abstract ( 910 )   PDF (645KB) ( 1625 )  
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Soil samples were collected from 12 tea gardens in the Fenghuangshan Tea Belt,East Guangdong for analysis of forms of Mn and Zn existing in the soil and their availability to tea,using a sequential chemical extraction procedure.It was found that in the soil,the mean Mn content was 337 mg·kg-1 and the mean Zn content 166.0 mg·kg-1.Both of then could be sorted into five fractions,which followed the order of residue>Fe/Mn-oxide-bound>organic-matter-bound>exchangeable>carbonate-bouned.The contents of Fe/Mn-oxide-bound and carbonate-bound Mn and nitrate-bound,organ-ic-matter-bound and Fe/Mn-oxide-bound Zn in the soil were all positively related to soil pH,while that of exchangeable Mn was negatively related;the content of organic-matter-bound Mn and Zn and Fe/Mn-oxide-bound Zn were all positively related to that of soil organic matter,while that of Fe/Mn-oxide-bound Mn was negatively related.The Mn content in tea leaves was in the range between 911.7-1219.4 mg·kg-1,and 1046.3 mg·kg-1 on average and also positively related to that of exchangeable,carbonate-bound and organic-matter-bound Mn,separately,but negatively related to soil pH.The Zn content in tea leaves was in the range between 34.3-59.5  mg·kg-1,and 42.0 mg·kg-1 on average and also positively related to that of exchangeable,organic-matter-bound and carbonate-bound Zn and soil organic matter content,separately.In conclusion,soil pH and organic matter content are the two important factors affecting on chemical speciations of Mn and Zn in the soil of the tea belt and their accumulation in tea leaves.
Iron Content in Lake Baiyangdian and Its Realations With Other Water Quality Factors
LIANG Shu-Xuan, WANG Yun-Xiao, Lü Jia-Pei
2011, 27(5):  13-17. 
Abstract ( 908 )   PDF (913KB) ( 1352 )  
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Water quality of Lake Baiyangdian was monitored from May 2009 to March 2010 to explore content and forms of iron in the waterbody,and their relations with other water quality factors.Results show that total Fe in the water ranged between 0.03 and 2.90 mg·L-1,and on average 61.11% of the samples from various monitoring sites exceeded the standard limit.Temporally iron cnontent in the water varied in the order of summer>autumn>spring>winter,and spatially,in the order of CK
Fertilizer Application and Nutrient Balance Under Different Cropping Systems in Taihu Lade Region,Jiangsu Province
XIA Xiao-Jiang, FU Wei, ZHU Li-Qun, CHEN Chang-Qing, BIAN Xin-Min
2011, 27(5):  18-23. 
Abstract ( 1005 )   PDF (627KB) ( 1372 )  
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To investigate contribution of agricultural non-point source pollution to eutrophication of the waterbody of Taihe Lake,Yixing,Liyang and Wuzhong of Suzhou,typical areas of the Taihu Lake region,were chosen as subjects for study on fertilizer application and nutrient balance under two different cropping systems,i.e.rice-wheat and rice-rapeseed.It was found that under the two cropping systems,an annual total of 556.2 and 488.0 kg·hm-2 of N fertilizers was applied,respectively,bringing N surplus rate up to 100.2% and 62.5%,separately.For the rice seasons, an average of 298.0 kg·hm-2 of N fertilizer was applied and significantly higher than the average of the wheat seasons (299.1 kg·hm-2) and of the rapeseed seasons (218.9 kg·hm-2).The annual P fertilizer application rate was 117.6 kg·hm-2 in the rice-wheat system and 116.7 kg·hm-2 in the rice-rapeseed system,and the the P surplus rates of the two systems weere quite low,being 9.0% in the former,and -7.4% in the latter.The annual K fertilizer application rate was the least among the three macro-nutrients,being 107.3 and 105.3 kg·hm-2 for the two systems,separately.As a result,both systems sufered K deficit,being over 50%.Obviously,in the two cropping systems,the application rate of nitrogen is much higher than that of phosphate and potassium,resulting in great N surplus;P application is quite reasonable and almost adequate to maintain soil P balance; and K application is the least in rate,leading to serious K deficit.
Quantity Dynamics and Spatial Distribution Pattern of Reaumuria soongorica Population in Suburbs of Lanzhou
ZHOU Zi-Xing, LI Yi, JIAO Jian
2011, 27(5):  24-31. 
Abstract ( 1313 )   PDF (1127KB) ( 1870 )  
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Quantity dynamics and spatial distribution patterns of the Reaumuria soongorica populations naturally distributed on the hills in the south and north of Lanzhou were studied.Age structures of the  Reaumuria soongorica populations were worked out by regression of ground diameter and their static life tables were plotted.Through survival analysis and spectral analysis,age structure dynamic indexes of the populations were calculated,thus revealing characteristics of their quantity dynmics.Based on the eight distribution indexes,types of the distribution patterns of the Reaumuria soongorica populations on time and space scales were determined.Results show that the Reaumuria soongorica populations on the two hills were appropriate in population density and crown density with their dynamic indexes being>0 and showing a rising trend.They both demonstrated an obvious periodicity.The populations were dominated with young and middle-aged plants.Mortality in each age class was basically stable,but peaked when the plants were in the transition period from Age Class Ⅱ to Ⅲ.The populations were close to Deevey's Type to to Ⅲ in suvival curve and quite obvious in spatio-temporal heterogeneity.The populations on the sunny slope were distributed in concentration,while on the shady slope they spread evenly.The population distribution patterns of the plants of different development stages varied regularly.Young individuals often gres together in patches,and when they grew older, their aggregation weakened sharply.
Eco-Securith Assessment of Xianlin New Urban District of Nanjing,China,Using GIS Technology and Fuzzy Matter Element Analysis
HAO Jing-Feng, LIU Hong-Yu, HU He-Bing, AN Jing
2011, 27(5):  32-36. 
Abstract ( 945 )   PDF (2213KB) ( 1202 )  
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An eco-security assessment index system was established,using a pressure-state-response(P-S-R)model and the analytic hierarchy process,while eco-security levels of Xianlin District before (2003) and after (2007) its construction were assessed using the GIS technology and the fuzzy matter element analysis method in a comprehensive way.The ecological security in the Xianlin New Urban District in Nanjing was evaluated.It was found that the ecological security level of Xianlin developed in two directions.The areas of both the eco-safe zone and the eco-unsafe zone increased with their proportion did from 9.6% to 22.3%,and from 12.9% to 15.0%,respectively,in the period of 2003-2007.The Qilin Subdistrict was almost at the threshold of eco-security and some others were developing from the threshold status to relatively safe one.The Qinglong Subdistrict remained almost unchanged.
Effect of Biochars Derived From Crop Straws on Cu(II) Adsorption by Red Soils
TONG Xue-Jiao, LI Jiu-Yu, JIANG Jun, XU Ren-Kou
2011, 27(5):  37-41. 
Abstract ( 1037 )   PDF (734KB) ( 1530 )  
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Effects of 4 kinds of biochars derived from straws of peanut, soybean, canola and rice,separately, on Cu(II) adsorption by the red soil samples from Jiangxi and Guangxi were investigated with batch method,to explore roles of the biochars in remedying heavy metal polluted red soils.Results indicate that incorporation of the biochars in creased Cu(II) adsorption by the soils.The effect was enhanced with decreasing pH of the system and with increasing application rate of biochars as well.With pH at 4.0 and  biochar added at 2%, Cu(II) adsorption increased by 97%, 79%, 51% and 54%,respectively,by application of biochar of canola,peanut,soybean and rice straws in the red soil from Jiangxi,and by 61% and 44%,respectively,by application of biochar of peanut straw and soybean straw in the red soil from Guangxi.The increment reached to 97% and 165%, respectively, when the addition of the biochars of the biochars was increased to 4%. Biochars normally carry negative charges and have ample amount of oxygen-containing functional groups on their surfaces, which greatly  increase electrostatic and specific adsorptions of Cu(II) in the red soils simultaneously,but it is more significant with the latter than with the former.Therefore,incorporation of biochars can effectively reduce mobility and bioavailability of Cu(II) in acid red soils.
Analysis on Polycyclic Aromatic Hydrocarbons in Petroleum Contaminated Soils and Its Ecological Risk Assessment
PAN Feng, GENG Qiu-Juan, CHU Hong-Jie, WANG Li-Li
2011, 27(5):  42-47. 
Abstract ( 851 )   PDF (856KB) ( 1594 )  
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Polycyclic aromatic hydrocarbons (PAHs) residue in petroleum contaminated soils around Zhongyuan Oilfield was investigated. Results showed that residue of PAHs in the soils ranged from 70.8 to 5013.2 μg·kg-1 and was mainly composed of multi-ring(over 3 rings) PAHs,of which high concentration of benzo(a)pyrene (BaP) was detected in all the soil samples with the highest being 996.9 μg·kg-1,in the surface soils in front of the christmas trees.By referring to the standard Canada uses in controlling PAHs contamination in the soils of its agricultural zones,Nemerow composite index method was appiled to the assessment of ecological risk of the contamination.Results show that the ecological risk of the soils around the wells,either in operation or recently closed,was quite high,and closely related to the working state and downtime of the wells and the distance from the christmas trees.The longer the downtime of a well, the lower the ecological risk of the soil around it,and the further to the well,the lower the risk.
Optimization of Conditions for Growth and Petroleum Degradation of Two Strains of Petroleum-Degrading Bacteria
YAO Yao, ZHENG Qing-Song, LIU Zhao-Pu, LONG Xiao-Hua, WANG Bo, LIU Guo-Hong, JIANG He-Ping
2011, 27(5):  48-53. 
Abstract ( 830 )   PDF (1276KB) ( 1335 )  
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In order to increase the oil degradation rate of the two strains of petroleum degrading bacteria,DH-5 and DH-9 isolated from the soil of the Shengli Oilfield,tests were done to screen out optimal composition of the medium for theri growth and environmental conditions for petroleum degradation.It was found that Strain DH-5 gres the bese when the medium was composed of 1 g·L-1 crude oil,400 mg·L-1 N sources,200 mg·L-1 P sources,20 mg·L-1 yeast  extract,and 10 mg·L-1 arginine(Arg),which was the most effective among acid,and it performed the best when it was in an environment being 7.0 in pH,20 in salinity and 15-30℃ in temperature.And under such conditions,oil degradation rate of DH-5 in creased 11.57 percent point.For best growth,DH-9 should be cultured in the medium composed of 1 g·L-1 crude oil,400 mg·L-1 N sources,100 mg·L-1 P sources,20 mg·L-1 yeast extract,and 10 mg·L-1 aspartic acid (Asp) which was the most effective among amino acid,and it did the best in an environment being 7.5 in pH,20 in salinity and 30℃ in temperature.Under such conditions,Strain DH-9 could degrade 64.10% of crude oil,oil degradation rate increasing 20.88 percent point.When the oil concentration reached 20 g·L-1 ,DH-9 was 158% and 129% higher than DH-5 inbiomass and oil degradation rate,respectively.The findings indicate that Strain DH-9 is significantly more tolerant to high concentrations of credu oil than Strain DH-5,but Strain DH-5 is more adaptable to low temperature than Stratin DH-9.Besides,both of the two strains show strong adaptability to higy salinity,which characterizes the local environment.
Effect of Moisture Content of Substance on Fermentation and Heat Production of Cattle Manure in Aerobic Composting
LEI Da-Peng, HUANG Wei-Yi, WANG Xiao-Hua
2011, 27(5):  54-57. 
Abstract ( 1161 )   PDF (531KB) ( 1498 )  
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Effects of initial moisture content on energy release from fermentation of the mixture of cattle dung and corn stalks as medium in an aerobic composting experiment were investigated.Relationship between loss of organic matter and heat production in the process was strdied.The experiment was desigened to have 5 levels of treatments of initial water content,i.e.(1)41%,(2)50%,(3)55%,(4)65%,and (5)75%,and heat was measured with oxygen bomb calorimetry.Results show that the temperature in the media rose and reached above 55℃ on D3 in all the treatments except Treatment 5.During the first three days,organic matter degraded the most rapidly and heat lost the most.In all the treatments except Treatment 5,heat production was positively related to initial moisture content.Treatment 4 was the most effective to activate aerobic composting,the highest in loss of organic matter,and the most variable in total heat.Its loss of organic matter reached up to 29.18% and total heat production 2236 kJ·kg-1.If the heat generated was all used to remove the moisture of the substance,the medium could be completely dried up.
Impact of Loading and Draining Conditions of On-site Subsurface Infiltration Systems With High Hydraulic Loading Rate on Purification of Domestic Wastewater
WEI Yu-Zhong, ZHAO Ti-Gang, HAN Wan-Ming, LI Kun, WU Fang, WANG Sheng
2011, 27(5):  58-62. 
Abstract ( 896 )   PDF (660KB) ( 1353 )  
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In order to investigate purification efficiency of the high-loading shallow underground infiltration system under the conditions of uneven influx of domestic sewage from widely scattered farm households and intermittent operation of the drainage pumps,4350 mm-tall infiltration columns were built up for an experiment to compare different loading and draining modes in effect of purifying domestic sewage with a daily hydraulic load of 12.5 12.5  cm·d-1.The experiment was designed to have four different loading and draining modes,that is,continuous loading,intermittent loading,free draining and intermittent draining.Results show that the average NH4+-N removal rates of all the columns were over 96%,and the average COD removal rates of the columns were in the range of 41.2%-67.7%.Of the four,intermittent loading and intermittent draining was the lowest in removal rate,but their drainages still met Grade Ⅱ criteria of the National Standard GB8978-1996"Integrated Standard for Drainage of Wastewater".The average TN removal rates of the columns were 17.5%-37.2%.The modes of intermittent loading and intermittent draining were the highest in TN removal rate,suggesting that to enhance nitrification/denitrification is the main way to increase N removal rate.The average TP removal rates of the four columns were in the range of 51.0%-78.0%.The columns of continuous loading and intermittent draining were the highest in TP removal rate,suggesting that to prolong stay of the wastewater in the column and to expand area of the contact surface between the wastewater and the filler are effective to increase P removal rate.the modes of intermittent loading and intermittent draining decreased COD removal rate,but were the most effective in removing N and P nutrients from wastewater.
Effects on Water Quality and Fishes of Copper Sulfate Complex Applied as Algaecide for Emergency Control of Algae Bloom
MIAO Liu, HONG Jun-Ming, LIN Bing
2011, 27(5):  63-66. 
Abstract ( 1178 )   PDF (680KB) ( 1601 )  
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Copper sulfate complex was appiled as algaecide for emergency control of algae bloom in eutrophicated ponds.Effects of the application on water quality and Cu enrichment in Tilapia sp. were studied.Results show that algae bloom was effectively put under control after the application,with chlorophyll a concentration falling from 298.98 to 40.71 μg·L-1 and turbidity from 14.45 to 5.70 NTU simultaneously.During the period of the treatment,the concentration of copper ions in water was lower than 0.3 mg·L-1 ;Ten days after the treatment,the algae began to in crease in biomass,bringing up chlorophyll a concentration from 40.71 to 125.29  μg·L-1 and turbidity from 5.70 to 12.15 NTU,and 22 days after the treatment,Cu2+ concentration in the water fell below the detetable limit.Various organs of Tilapia sp. followed the order:liver(512.50 mg·L-1 )>gill(17.00 mg·L-1 )>muscle in Cu enrichment ability.No obvious Cu accumulation was found in fish meat.In addition after the treatment,Cu accumulation in gills of the fish declined significantly.
Effect of Copper Stress on Lethal Rate,Cu Enrichment,CAT and SOD Activities of Bellamya aeruginosa
NAN Xu-Yang , DAI Ling-Peng
2011, 27(5):  67-71. 
Abstract ( 915 )   PDF (796KB) ( 1492 )  
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Effects of copper on lethal rate and Cu enrichment of Bellamya aeruginosa and CAT and SOD activities in the hepatopancreas of Bellamya aeruginosa under Cu stress were studied. Bellamya aeruginosa was collected from a river in Chashan of Ouhai,Wenzhou City,Zhejiang Province.Results show that Bellamya aeruginosa was quite capable of tolerating low concentrations of Cu2+(1.0 and 2.0 mg·L-1),but showed a relatively high hethal rate when ρ(Cu2+)was in the range from 4.0 to 8.0 mg·L-1.When  ρ(Cu2+)was 0.2-0.8 mg·L-1,Bellamya aeruginosa enhanced its Cu enrichment with its exposure to the toxicant getting longer and the toxicant higher in dosage.However,when ρ(Cu2+)reached 1.6 mg·L-1,its Cu enrichment declined with the duration of its exposure.Cu stress significantly affected CAT and SOD activities in the hepatopancreas of Bellamya aeruginosa .
Effects of Cuprous (Cu2O) and Cupic Hydroxide [Cu(OH)2] on Activity of Antionxidase and Content of Chlorophyll in Vallisneria natans
HU Fang, PU Hai-Qing, CHEN Liang-Yan, CHENG Shu-Pei
2011, 27(5):  72-78. 
Abstract ( 1007 )   PDF (1181KB) ( 1394 )  
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Effects of two wettable copper powders,cuprous oxide(Cu2O)and cupic hydroxide[Cu(OH)2)],varying in concentration on activity of antioxidases [superoxide dismutase(SOD),ascorbate (APX),and peroxidase (POD)],content of malondialdehyde(MDA) and content of chlorophyll in leaes of Vallisneria natans were studied.Results show that exposure to Cu2O W.P.(0.15-1.5 mg·L-1)for 7 days significantly increased specific activities of superoxide dismutase(SOD),ascorbate peroxidase (APX) and peroxidase (POD) in the leaves of the plant.In the treatment,highest in concentration of the pollutant (1.5 mg·L-1),sapecific activities of the three anti-oxidative enzymes increased by 49.0%,77.0% and 39.0%,respectively,and content of MDA dramatically increased by 46.9%,but content of total chlorophyll decreased by 42.6%.After the plant was exposed to the toxicant for 14 days,the specific activities of the three anti-oxidative enzymes in the plant receded to a varying extent,the content of MDA returned to its normal level,and the content of chlorophyll somewhat recovered.When exposed to Cu(OH)2 W.P.(01.-1.0 mg·L-1 )for 7 days,the plant in the treatment highest in concentration (1.0  mg·L-1)of the toxicant showed a similar trend in specific activities of anti-oxidative enzymes,MDA level and chlorophyll content.And when the exposure lasted for 14 days,the activities of anti-oxidative enzymes and the MDA level fell back to their normal ranges,and the content of total chlorphyll also went up.The above-listed findings indicate that at the early stage of the cupper stress caused by cuprous oxide and cupic hydroxide,activities of the anti-oxidative enzymes in Vallisneria natans ascend in respingse to oxidative stress,causing certain oxidative damage to membrane lipid and decline of chlorophyll content.But with duration of the exposure extending,the plant gradually gets adapted to the stress,with oxidative damage mitigated and chlorophyll content recovered.
Universal Index Formulae for Eco-Environment Quality Assessment Based on Normalized Index Transformation
ZHANG Zheng-Jian, LI Zuo-Yong, YU Chun-Xue
2011, 27(5):  79-85. 
Abstract ( 1005 )   PDF (788KB) ( 1345 )  
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In order to establish the universal index formulae, which should be scientific,reasonable,simple and practical in application to eco-environment quality assessment,based on determination of the eco-environment assessment index systems and grading standards for typical regions,proper reference values and transformation formulae were set for each eco-environment index,separately,so as to minimize defferences of the transformation values,especially logarithmic values of  the transformation values from the standard values of different indexes of the same grade.Thus,the various indexes expressed by transformation values can be held to be equivalent to a certain index.Therefore,various types of eco-environment quality assessment index formulae with transformantion values expressing various indices can all be replaced by eco-environment quality assessment index formulae of corresponding "equivalent"indices.Meanwhile universal parameters in each formula were optimized repeatedly with the immune evolutionary-particle swarm optimization-shuffled frog leaping algorithm under the condition that certain optimization objective criteria were satisfied.As a resuly,5 forms of eco-environment quality assessment universal index formulae were gained,i.e.logarithmic power function,Weber-Fechner law,Γ distribution function,pollution harm S-type function and weighted additive power function,which are applicable to 23 items of eco-environment indices after optimization.Furthermore,reliabilities of 5 formulae were analyzed theoretically and tested by practice.
Determination of Estrogens in Water Samples From Wastewater Treatment Plant Using Ultra-Performance Liquid Chromatography-Electrospray Tandem Mass Spectrometry Method
Tan-Li-Chao, GE Feng, SHAN Zheng-Jun, WANG Yi
2011, 27(5):  86-92. 
Abstract ( 1469 )   PDF (1062KB) ( 1642 )  
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An instant estrogen screening and determination method,using the HLB solid-phase  extraction and ultra-per-formance liqulid chromatography-electrospray tandem mass spectrometry (UPLC-MS/MS)in a multiple reaction monitoring (MRM)mode,was established for determination of seven estrogens(estradiol valerate,ethynylestradiol,estriol,estradiol,hexestrol,estrone and diethylstilbestrol) in the influent and final effluent of a wastewater treatment plant.Conditions for performances of soild-phase extraction(selection of extraction cartridge,eluate and its volume used for elution,pH adjustment of the water sample,and rinsing solution)and for UPLC-MS/MS analysis (mobile phase and gradient,capillary voltage,cone voltage,RF lens voltage,collision energy,ion source temperature,desolvation gas flow and cone gas flow)were optimized.In the case that all the seven estrogens were in the linear range of 1-100 μg·L-1,in mass concentration,all the determination coefficients(r2)of the regression equation were over 0.9972,and the detection limit of the method ranged from 4.40 to 10.27 ng·L-1 for estrogens.When the mass concentration of estrogens was raised to the range of 20-100ng·L-1,the recovery rates of the target substances in the influent and effluent water samples were in the range from 70.3% to 95.1% and from 72.6% to 96.7%,separately,with relative standard deviation(RSD) below 10.4% and 9.5%,separately.This method was applied to determine estrogens in influents and effluents of four major integrated wastewater treatment plants in Nanjing.It was found that concentrations of estradiol valerate,estriol and estrone reached as high as dozens and even hundred of ng·L-1 in the influenets and several or dozens in the final effluents.
Determination of Factors Affecting Glomalin-Related Soil Protein With Bradford Method
Lü Hua-Jun , LIU De-Hui, DONG Yuan-Hua, LI Jian-Gang
2011, 27(5):  93-97. 
Abstract ( 1065 )   PDF (735KB) ( 1435 )  
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Glomain-related soil protein (GRSP) is an important indicator in assessing soil health. On the basis of the researches done by predecessors,further investigations were conducted of effects of soil particle size,soil sample storage conditions and delay of centrifugation of the extract after high-temperature extraction on quantification of GRSP with the Bradford method.Results show that soil particle size significantly affected extraction and determination of easily extracted GRSP(EEG).The content of EEG extracted from samples that passed a 0.074 mm sieve was significantly higher than that from samples that passed 0.149,0.25,and 1 mm sieves,separately.However,the content of total GRSP(TG)did not vary with soil particle size,which indicate that for determination of TG,it is advisable to use soil samples that pass 1 mm sieves.Storage conditions also affected determination of EEG and TG.The content of EEG determined of the soil samples of low organic matter content at -20℃ for 18 months was obviously more than that stored at room temperature for the same length of time,while the content of EEG determined of soil samples of high organic matter content stored at room temperature showed a reverse trend.And TG determined of soils of three organic matter content levels stored at room temperature was obviously higher than that stored at -20℃.So to minimize the effect of organic matter degradation,soil samples should be stored at low temperature.Delay of centrifugation of extracts may lead to decrease in the value of EEG determination.It is advisable to have the extract centrifugated within 1h.However,there is no significant difference betwwen delays of centrifugation within 2 h for TG determination.
Environmental Scanning Electron Microscope(ESEM) Observation of Microbial Colonization Process in Straw Composting
PIAO Zhe, LI Yu-Min, MA Shuai, CHEN De-Ying, MEI Li-Juan, YIN Shi-Xue
2011, 27(5):  98-100. 
Abstract ( 868 )   PDF (882KB) ( 1512 )  
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To understand the biodegradation processes of rice straw in compostiong,samples of the straw were taken at different composing stages for observation on the environmental scanning electron microscope(ESEM) to explore distribution of microorganisms in the straw and their effects in decomposing the straw from the angle of mechanical action.Results show that no microorganisms were found on the surface of raw straw,and they began to appear on the surface of straw at the initial stage of composting.With the composting proceeding,the microorganisms grew dense on the surface and were also found in cracks formed on the straw in decomposing.Microorganisms participating in decomposing of straw were distributed in colonies,and dominated with cocci and hyphomycete,which varied sharply in individual size.The observation reveals that large-sized hyphomycetes intrude into cracks formed in the straw being composted creating mechanical action that helps break down the straw.
Effect of Soil Amendments on Gronwth of Soybean in Coal Gangue Contaminated Soil
MA Shou-Chen, Lü Peng , LI Chun-Xi, GUO Zeng-Chang, NIE Xiao-Jun
2011, 27(5):  101-103. 
Abstract ( 975 )   PDF (439KB) ( 1378 )  
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In a pot experiment using coal gangue contaminated soil with fly ash and dairy manure dung,separately or in combination,as soil amendment,soybean was planted to study effects of the amendments on the growth,photosynthesis and yield of th plant.Four treatments were designed:CK(control),Treatment T1(fly ash),Treatment T2(dairy manure),T3(fly ash and dairy manure in combination).Results show that all 3 treatments improved soybean in plant height,leaf area and number of root nodules,but followed the order of T3>T2>T1 in effect at all the growth stages,and increased chlorophyll content and photosynthesis rate of the soybean at the flowering and seed-filling stages,more significantly in Treatment T3 than in Treatment T2 and Treatment T1.Besides they also significantly raised pod number perplant,100-grain weight,seed weight per plant and yield.The yield of the plant was in creased by 68.47% in Treatment T3,by 40.99% in Treatment T2 and by 30.63% in Treatment T1 over that in control.
Residue and Degradation of Metamifop in Paddy Field
KONG De-Yang, SHI Li-Li, SHAN Zheng-Jun, WU Wen-Zhu
2011, 27(5):  104-107. 
Abstract ( 1422 )   PDF (529KB) ( 1598 )  
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Field experiments were conducted in Jiangxi and Jiangsu Provinces,separately,of spraying metamifop(10% emulsifiable solution)in paddy fields to explore dynamics of metamifop residus in the paddy fields with the accelerated solvent extraction(ASE),gel permeation chromatography(GPC) and high performance liquid chromatography(HPLC)methods.Results show that metamifop degraded quickly in the plant and water,but not so in the soil.The half-life of metamifop in plant,water and soil was approximately 3.5 and 2.2 days,1.3 and 2.3 days,11.7 and 20.2 days at Nanjing and Nanchang,respectively.When a paddy field was sprayed once with 10% metamifop emulsifiable solution at the highest recommended dose and even 2 times of that value,no residue of the substance was detected in rice straw,rice hull,brown rice and paddy soil at the harvest,which suggests that metamifop is a kind of pesticide low in residue and easy to degrade.
Effect of Fortified Aquatic Plants-Microorganisms System on Purifying Macrobrachium nipponense Culturing Water
WU Wei, QU Jian-Hong, WANG Xiao-Juan, XU Jiao-Yang, QIAN Zhi-Lin
2011, 27(5):  108-112. 
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A fortified aquatic plants-microorganisms system in a Macrobrachium nipponense rearing pond was established by planting Hydrilla verticillata based aquatic plants and then adding a kind of compound microbial preparation,containing at least 108 g-1 viable bacteria,to study effect of the system on purifying the waterbody.Results show that after 40 days,by making full use of the enormous surface area of the auatic plants,the viable microbes grew and formed a fixed biofilm,thus increasing the number of bacteria and fungi in the plant area and its neighboring waters by 25%-69%,and intensifying the self-purifying effect of the waterbody.Through synergic actions,the fortified aquatic plants-microorganisms system could not noly improve utilization of nitrogen,phosphate and organic substances,thus promoting growth of the biological system per se,but also decrease NH4+-N、NO2--N、NO3--N、TP and PO43--P contents in the water,suppress rapid increase in TN and COD,increase dissolved oxygen(DO) and compete with alga for resources for growth,thus lowering abundance of alga in and stabilizing pH of the waterbody.The findings indicate that the fortified aquatic plants-microorganisms system is an effective in-situ biological purification system for Macrobrachium nipponense rearing water.The optimum aquatic plant coverage of the water surface is 40%,when the added compound microbial preparation is 1.0mg•L-1 in biomass concentration.