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Table of Content

Volume 28 Issue 5
25 September 2012
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Spatial-Temporal Evolution of Land Use/Cover Change in Middle Section of Heihe Basin Since 1975
JIANG Peng-Hui, ZHAO Rui-Feng, ZHAO Hai-Li, FAN Jie-Ping, WANG Jian-Zhen, LIU Chao
2012, 28(5):  473-479. 
Abstract ( 807 )   PDF (1148KB) ( 2111 )  
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The Heihe River is one of the most important inland rivers in the northwest arid region of China.With its economy and population growing rapidly,the Heihe basin is faced with deteriorating ecological environment in recent years.Therefore,it is very important and urgent to analyze changes in land use/cover in the area,and their driving forces,and eco-environment problems.The middle section of Heihe basin was chosen as a research area,of which the remote-sensing images of 1975,1987,1992,2001 and 2010 were picked as basic data for comprehensive analysis using corrlation analysis method and principal component analysis method in combination with transfer matrix.Variation amplitude,dynamic degree and intensity of land use were set as indices.Results show that within 35 years after 1975,the proportions of cultivated land and land for urban and rural housing and public facilities and for industrial and mining expanded steadily by 5.60 and 0.46 percentage points,respectively,and the area of grassland and water surface decreased by 3.87×104 and 0.41×104hm2,respectively.Among the various types of land use in the study,cultivated land was the highest in variation amplitude,reaching 0.1604% and was followed by grassland.The conversions of grassland into farmland and wasteland,and the coversion of wasteland into farmland and grassland and the coversion of forestland into grassland and vice versa were the main trends of the landuse variation.The major force driving the variation of the land use is development of the social economy.
Residuals of Organochlorine Pesticides DDT and HCH in Surface Sediments of the Pearl River Estuary
Mu-San-Niu, LAI Zi-Ni, WANG Chao, LI Xiu-Li, LI Yue-Fei, ZHAO Li-Na, GAO Yuan
2012, 28(5):  480-485. 
Abstract ( 805 )   PDF (1246KB) ( 1735 )  
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Dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane(HCH), arewere common organochlorine pesticides extensively used for agriculture and vector control purposes due to their low cost and high effectiveness. As they are quite persistent, they become ubiquitous. And as they are potentially toxic and bioaccumulative in nature, they accumulate in organisms which once get exposed to them, and eventually cause adverse effects on both human and wildlife, such as cancer, damage to the nervous system, reproductive disorders, and disruption of the immune system. However, little has been done on this issue of the Pearl River estuary. So, during the period from August, 2010 to May, 2011, samples of surface sediments were collected four times at the 8 outlets of the Pearl River esturay for analysis of residues of DDTs(p,p’-DDE, p,p’-DDD, o,p’-DDT, p,p’-DDT)and HCHs(a-HCH, β-HCH, γ-HCH, δ-HCH)using the gas chromatograph-electron capture (GC-ECD) method. Results show that total DDTs contents in the surface sediments from  the Pearl River ranged from 1.02 to 3.08 μg?kg-1 (dry weight) and averaged 1.91 μg?kg-1, and total HCHs contents ranged from 0.21 to 0.41 μg?kg-1 and averaged 0.31 μg?kg-1. DDTs were much higher than HCHs in average content, and p,p’-DDT contributed the most, ranging from ND to 7.66 μg?kg-1, with a mean of 2.12 μg?kg-1. In most of the samples, wα-HCH)/wγ-HCH)ratios were lower than 3, implying that a-HCH has mostly been degraded or that lindane is gradually taking the place of industrial HCHs as the major source of the pollutant HCHs in the water environment and w(DDT)/w(DDD+DDE) ratios higher than 2, indicating that besides residuals of the pesticides used in the past, new input of DDTs type pesticides is found.
Species Diversity and Structural Characters of Desert Plant Communities in Lower Reaches of Tarim River
BAI Yuan, XU Hai-Liang, ZHANG Peng, ZHAO Xin-Feng, FU Jin-Yi
2012, 28(5):  486-492. 
Abstract ( 800 )   PDF (1441KB) ( 1874 )  
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Based on the data of plant communities collected from 29 sampling sites,species diversities and structures of the natural plant communities in the lower reaches of the Tarim River were analyzed from the angle of different environmental gradients,using species diversity,richness and eveness indices.Results show that (1) the study area had a total of 14 genera of plants,belonging to 10 families,with Tamarix ramosissima,Lycium ruthenicum and Populus euphratica being the first three in frequency of occurrence and P.euphratica being the highest(0.384),T.ramosissima the next highest (0.230) and Halogeton arachnoideus the lowest(0.002) in the importance value,and P.euphratica being dominant species was mainly distributed in areas less than 500 m from the river.(2) Groundwater tables along the river lowered from the upper reaches to the lower reaches,expcept for the Yiganbujima Section,and so did the specties diversity on the whole and arbor-shrub-herb-dominated communities were gradually changed into arbor-shrub-dominated one;while getting farther away from the river,the communities first increased and then decreased in density and coverage,and the plant community structures gradually shifted from arbor-shrub and arbor-shrub-herb to shrub-herb or shrub.
Dynamics of Pteroceltis tatarinowii Population in Langya Mountain of Anhui Province
ZHANG Xing-Wang, ZHANG Xiao-Ping, GUO Chuan-You, DING Jian-Hua
2012, 28(5):  493-499. 
Abstract ( 783 )   PDF (1029KB) ( 1684 )  
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Based on the theories of population life table and survival analysis, a static life table and curves of the survival rate, mortality rate and vanishing rate as well as survival function curve, of Pteroceltis tatarinowii population in the Langya Mountain of Anhui Province were worked out for analysis of quantitative characteristics of the population using the diameter at breast height(DBH) classification method and the section smoothing technique.Further on for analysis of dynamics of the population quantity using the method of quantification of population dynamics and the time series prediction model were used. Results show that 1) the population of Pteroceltis tatarinowii in the Langya Mountain is of the type of steady growth. The structure of DBH class of the population appeared roughly in the shape of an invert “J”; trees middle and young in age were relatively high in number, but those old in age relatively low. Although the population may be subject to certain fluctuation during its development process, the two dynamic indexes of Vp,i and Vp,i' (taking into account the external interference) of the population quantity were both higher than zero. 2) The curves of the mortality rate and the vanishing rate of the population varied in a similar trend, each with two peaks popping up at the 2nd age class and the other at the 11th or 12th. Statistic test shows that the survival rate curve tends to be of the type of Deevey-Ⅱ. 3) The survival rate of the population decreased monotonically, while the cumulative mortality rate increased in the same manner. The falling trend of the survival rate was more apparent in the early stage than in the late stage, whereas that of the cumulative mortality rate was just the reverse. The survival functional curve shows that the Pteroceltis tatarinowii population is characterized by weakness in the early age period, stableness in the middle age period, but decline in the old age period. 4) The time sequence model predicts that young individuals would be relatively abundant, and the population will show a trend of steady growth in the next 2, 4, 6, 8 and 10 years.
Strategies for Conservation of Genetic Diversity and Resources of Wild Silvetia siliquosa Population in Rongcheng City
LIU Wei, CUI Jing-Jing, WANG Xiang-Yu, LI Mei-Zhen
2012, 28(5):  500-504. 
Abstract ( 989 )   PDF (900KB) ( 1351 )  
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A total of 30 individuals were collected from the local wild Silvetia siliquosa population were analyzed( for genetic diversity and genetic structure using the RAPD method (random amplified polymorphism DNA). Results show that a total of 112 polymorphic loci were detected with the aid of 21 polymorphic 10-based random primers, reaching 93.75 in percentage, and its Nei’s gene diversity was 0.351 5±0.135 2 and Shannon diversity index 0.504 6±0.112 6. Of the three subgroups sorted into the same order based on UPMGA analysis, genetic differentiation ranged from 0.134 9 to 0.218 9 and gene flow was 1.779 3. The result indicatesd that the wild S. siliquosa population in Rongcheng was quite high in genetic diversity and displayed obvious genetic differentiation, and the genetic resources of the population was not affected by genetic drift. In light of the status quo of the genetic resources of the local S. siliquosa population, it is essential to intensify in situ conservation of the existing population and restore size of the population, and avoid degradation of the resources through inbreeding when samples are collected for preservation through breeding.
Impacts of Invasion of Ipomoea cairica on Plant Community and Soil Fertility
ZHU Hui, WU Shuang-Tao
2012, 28(5):  505-510. 
Abstract ( 825 )   PDF (841KB) ( 1918 )  
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Ipomoea cairica (Convolvulaceae), a perennial herbaceous liana, has become a major invasive weed with strong invasiveness in the east part of Guangdong Province, China. In a field investigation, five patches of land that had been heavily invaded by I. cairica were chosen as sample plots, and five adjacent patches of land free of I. cairica or other invasive plants were set as control group. Coenological survey of the plants in all the 10 plots was performed using the quadrat method for calculation of species diversity index, and soil samples were collected from the sample plots for analysis of soil enzyme activity and physico-chemical indices, so as to explore interactions between I. cairica and eco-factors of the invaded area and evaluate impacts of the invasion on ecosystem. Results show that the invasion decreased plant richness and diversity to a significant (P<0.05)or an extremely significant extent(P<0.01), and its effect of crowding out native species was especially obvious. In all the sample plots, except for the forest park plot, the invasion increased the activities of invertase, urase, phosphatase and nitrate reductase (NR), which are closely related with soil fertility, notably by 26.91% -55.52%. Besides, it increased the contents of TN, AN, TK and AK, but reduced the contents of TP, AP and OM in the soil, all to a significant (P<0.05) or an extremely significant extent (P<0.01). The findings suggest that invasive weed I. cairica can alter the structure and composition of the community and improve soil enzyme activities and soil nutrient levels, thus forming a micro-ecoenvironment that is beneficial to development and growth of the plant per se and expansion of its population.
Characteristics of Soil Nutrient Loss with Interflow fFrom Uplands as Affected by Land Uses in Low Hill Region of Chaohu Basin
CHANG Long-Fei, WANG Xiao-Long, LI Heng-Peng, HU Feng
2012, 28(5):  511-517. 
Abstract ( 806 )   PDF (1177KB) ( 1660 )  
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Six major types of land use (deserted farmland, bare land, shrub land, grassland, Pinus massoniana forest, and artificially restored forest) in the low hill region of Caohu Basin were chosen as subjects in a study to explore for characteristics of soil nutrient loss with soil interflow as affected by the land use in the region. Stationary observation and sampling of soil interflows for analysis were conducted. Results show that among the six types of land use, shrub land and grassland were the highest in probability of interflow occurrence, while bare tailing land was the lowest and had interflows only in the top 20 cm soil layer. For the nitrogen concentration in soil interflow, it was found the highest in bare tailing land and the lowest in artificially restored forest. However, phosphorus content in interflow was the highest in deserted farmland and the lowest in bare tailing land; Specifically, the nitrogen in soil interflow was found mainly in the form of dissolved NO3--N, of which the concentration displayed a decreasing trend with the arrival of the rainy season, but a falling and then rising trend with soil depth. The phosphorus lost with soil interflow was mainly in the form of dissolved organic phosphorus, of which the concentration displayed a decreasing trend with soil depth. Correlation analysis showed the that both nitrogen and phosphorus concentrations in soil interflow were significantly related with total land coverage, vegetation evenness and soil nutrient level, but insignificantly with amount and intensity of rainfall. Owing to the flourishing mining industry in the region, it is important to take into account the effect of dry and wet depositions when analysis is done of N content in soil interflow in the region.
Effects of Livestock Manure on Distribution of Heavy Metals and Antibiotics in Soil Profiles of Typical Vegetable Fields and Orchards
PAN Xia, CHEN Li-Ke, BU Yuan-Qing, ZHANG Hai-Bo, WU Long-Hua, TENG Ying, LUO Yong-Ming
2012, 28(5):  518-525. 
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Samples of different kinds of animal and poultry manures and of soils from typical vegetable fields and orchards of Hangzhou area that had been applied with these manures, were collected separately for analysis of concentrations of heavy metals and pollution of 14 selected antibiotics to study the effects of long-term application of the manures on distribution of heavy metals and antibiotics in soil profiles of these fields.Results show that of the three kinds of livestock and poultry manures, pig manure was the most liable to soil pollution, for it contained 197.0 mg•kg-1 of Cu, 947.0 mg•kg-1 of Zn and 1.35 mg•kg-1 of Cd. Among the lands under different patterns of land use, greenhouse vegetable lands were the most prominent in having heavy metals accumulated in the surface soil, especially Zn and Cd, being 203 and 0.48 mg•kg-1, respectively, in the 0-20cm soil layer. The 14 selected antibiotics, including tetracycline (TC), oxytetracycline (OTC), chlortetracycline (CTC), doxycycline (DXC), sulfadiazine (SD), sulfamethoxazole (SMZ), sulfamethazine (SMX), norfloxacin (NFC), ofloxacin (OFC), enythromycin-H2O (ETM-H2O), roxithromycin (RTM), chloramphenicol (CPC), thiamphenical (TPC) and florfenicol (FFC), varied significantly in concentration and distribution in soil profiles with land use pattern. They decreased rapidly in concentration with soil depth, but some of them were still detectable in the 80 -100 cm soil layer. Compared to orchards, the vegetable lands had more antibiotics accumulated in the surface soil layer as residue, which was 39.5 μg•kg-1 in concentration and composed mainly of TCs and fluoroquinolones antibiotics, reaching 34.3 and 4.75μg•kg-1, respectively. Obviously, long-term application of livestock manure in farmland might result in the combined pollution of heavy metals and antibiotics, and is apparently a potential ecological risk.
Effects of River Sediment Application on Functional Diversity of Soil Microbial Community and Growth of Winter Wheat
HUA Jian-Feng, YANG Yi-Ru, XU Jian-Hua, WANG Xing-Xiang, YIN Yun-Long
2012, 28(5):  526-531. 
Abstract ( 755 )   PDF (937KB) ( 1573 )  
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Soil microbial organisms are an important components of farmland ecosystems, and soil microbial community structure and activity reflects quality of the soil to some extent. A pot experiment was conducted to investigate effects of application of river sediment on population and functional diversity of soil microbe and Cd content of winter wheat grain under four different sediment application levels, 0 (control), 20, 60 and 100 g•kg-1. Results show that spike quality and 1 000-grain weight of wheat were much higher (P < 0.05) in Treatments 60 and 100 g•kg-1 than in control and no significant difference was found in grain Cd content between the four river sediment application rates. Compared with control, application of river sediment had no significant influence on populations of bacteria, fungi and actinomyce, and no significant influence on average well color development (IAWCD), Shannon index (H'), Simpson index (D) and McIntosh index (U) of microbe at 96 h, either. Principal component analysis (PCA) demonstrated that only by PC3 which explains 14.22% of the total variable variance, can the differences between control and the treatments be distinquished in carbon utilization of soil microbial community, while PC1, PC2 and PC4 which explains 21.76%, 16.32% and 11.62%, respectively, of the total variable variance are useless in this aspect. All of the above imply that in this study river sediment application rate has no significant effects on Cd content of winter wheat grain, functional diversity of soil microbe and soil quality.
Impacts of 2,4’-DDT on Growth, Reproduction and Vitellogenin(Vtg) of Zebrafish
DING Ke, HAN Zhi-Hua, WU Di, SHAN Zheng-Jun
2012, 28(5):  532-538. 
Abstract ( 769 )   PDF (3177KB) ( 1798 )  
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Using zebrafish’s vitellogenin as a biomarker of estrogenic pollutants, a comparative study was carried out to determine impacts of 2,4 '-DDT, varying in concentration, on growth, development, reproduction and vitellogenin in vivo. Results show that in water containing 2 and 10 μg•L-1 of 2,4 '-DDT, the egg yield and egg fertilization rate of fish decreased significantly, as compared with the blank group (P<0.05). In water containing 0.2, 2, 10 μg•L-1 of 2,4 '-DDT, the fish increased significantly in its hepaticosomatic index (P<0.05); A significant increase was observed in vitellogenin level of male fish treated with 10 μg•L-1 2,4 '-DDT (P<0.05), and of female fish treated with 0.2, 2, and 10 μg•L-1 2,4 '-DDT (P<0.05). And the increase got more significant with the exposure increasing in concentration . SDS-PAGE and Western blotting analysis revealed that a Vtg fragment appeared in the blood of male fish, which indicates that the 2,4 '-DDT has estrogenic effects on zebrafish.
Degradation of Flufiprole in the Environment
HE Jian, KONG De-Yang, WU Wen-Zhu, SONG Ning-Hui, SHAN Zheng-Jun
2012, 28(5):  539-543. 
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Degradation of flufiprole in water via various mechanisms,hydrolysis and photolysis,and in 3 different types of soil was investigated under laboratory conditions.Results show that flufiprole is rather stable and not easy to break down in acid and neutral solutions,but easily gets hydrolyzed in alkaline solution with half-life being 26.7 d in solution 9.0 in pH and 50 ℃ in temperature.Through identification of its hydrolytic products,it could be inferred that the hydrolysis of flufiprole in water is alkali-catalyzed one.Under the artificial light of a Xe lamp,2500 lx in light intensity and 25 μW·cm-2,flufiprole has a half-life of 1.5 hour,and its photolytic produce was mainly fipronil.But in the paddy soil of Taihu,red soil of Jiangxi and fluo-aquic soil of Shaanxi,flufiprole was found almost unchanged after 180 days of incubation,suggesting that flufiprole is hard to break down in soil.
Effects of Fractions of Natural Organic Matter in Sediment on Sorption Characteristic of Ammonium Nitrogen
WANG Er-Li, WANG Si-Qi, XUE Yang
2012, 28(5):  544-549. 
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In order to estimate amounts of the ammonium nitrogen adsorbed by different fractions of natural organic matter in sediment, effects of fractions of natural organic matter in sediment on sorption of ammonium nitrogen were investigated by batch experiments of equilibrium adsorption. Results show that sorption capacity of the sediment reduced dramatically after its organic matter was removed, with normalized sorption capacity and partition coefficient equaling only to 55.30% and 69.49%, respectively, that of the heavy fraction of organic matter, indicating that organic matter is a main factor affecting sorption of ammonium nitrogen on sediment. However, sorption of ammonium nitrogen in the light fraction of organic matter was dominated by distribution (Koc=85.57). Stably combined humus and tightly combined humus were important adhesive substances in the formation of loose and porous aggregate structure of the sediment. In the heavy fraction of organic matter, besides the mechanism of distribution, sorption of ammonium nitrogen was controlled by the mechanism of pore-filling, (Гmoc=3 477.81 mg·kg-1).Furthermore, tightly combined humus (humin) played a leading role in sorption of ammonium nitrogen, (Гmoc=5 857.78 mg·kg-1). Consequently, in estimating amount of the ammonium nitrogen adsorbed by the light fraction of organic matter, stably combined humus and tightly combined humus, it is advisable to count it as 0.32, 1.21 and 1.68 times, respectively, of that by the heavy fraction of organic matter.
Characteristics of Polybrominate Biphenyls Pollution of a Typical E-Waste Disposal Site and Soils in Its Surroundings
MOU Yi-Jun, ZHOU Chun, CHEN Tao, YU Bin-Bin, YIN Xiao-Hui
2012, 28(5):  550-553. 
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Concentrations and distribution of 10 PBBs (polybrominate biphenyls, i.e. PBB-3, PBB-15, PBB-18, PBB-52, PBB-101, PBB-153, PBB-180, PBB-194, PBB-206 and PBB-209) in the soils at a typical e-waste disposal site and its surroundings were analyzed sequentially using the method of accelerated solvent extraction (ASE), gel permeation chromatography (GPC) and gas chromatography-mass spectrography (GC-MS).Results show that e-wastes caused PBB pollution, similar in extent, to the site and the surrounding area, with total PBB content in the soil averaging 2.81×10-3 and 2.50×10-3  mg•kg-1, respectively, reflecting a lower pollution level   Of the ten PBBs, PBB-153, PBB-194, PBB-206 and  PBB-209 were the main pollutants because they arehave been commonly used. The distribution of total PBBs along the soil profile showed a decreasing order of 40-60, > 0-20 ,> 20-40 > 60-80 cm. PBB-209 was the major one, being the highest in proportion. So that, in monitoring PBBs pollution in similar regions, it is advisable to determine the content of PBB-209 alone and then multiply the result by empirical coefficient 1.78. Such method is adequate for reflecting the PBBs pollution of the regions.
Species of Duckweeds in Summer in Jiangsu Province and Water Environments They Grow in
WU Xue-Fei, LIU Lu-Jia, MA Han, LIU Yang, ZHOU Ming-Yao, QIAN Xiao-Qing
2012, 28(5):  554-558. 
Abstract ( 1049 )   PDF (829KB) ( 2247 )  
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Surveys were conducted of duckweeds-grown water bodies scattered in industrial, residential, and farming areas in a number of cities or counties to investigate species of the duckweeds and water samples collected for analysis of extent of eutrophication of the water bodies, and further clarify relationships of the distribution of duckweeds with pH and contents of ammonium, nitrate, total nitrogen and total phosphorus in the water. Results show that duckweeds tend to flourish in calm water rather than flowing water, and in water bodies in the farming and residential areas rather than in industrial areas. In summers of Jiangsu Spirodela polyrrhiza, Lemma minor, Wolffia arrhiza and Spirodela oligorrhiza are the most common duckweeds found in water bodies, and no trace of Lemma perpusilla and Lemma trisulca was found during the survey. Spirodela polyrrhiza and Lemma minor were found in all the water bodies surveyed, with water pH varying in the range of 4.5-7.5. The results also show that duckweeds grow well in water bodies, high or low in N and P concentrations, ranging from 0 to 42,0.2 to 2.0, 0.2 to 45 and 0.02 to 13 mg·L-1 for ammonium, nitrate, total nitrogen and total phosphorus, respectively. No evidence was found showing that any close relationship existed between duckweeds distribution and concentrations of nitrogen and phosphorus in the water. In industrial areas, there are a variety of factories, including chemical plants, clothing factories, pharmaceutical plants, mechinary accessories factories, etc., discharging a high volume of waste containing heavy metals and organic matters. In water bodies in or near the industrial areas, symbiosis of Spirodela polyrrhiza and Lemma minor and occasionally Wolffia arrhiza, too, is commonly observed. Therefore, in exploiting the effect of duckweeds removing nutrient substances, like N and P from water, priority should be given to native species of duckweeds dominant in the season and the complex symbiotic system of different species of duckweeds so as to maximize the production of duckweeds and their N and P removing rate.
Reduction of Hexavalent Chromium by Nanoscale Fe0 and Its Influencing Factors
LIU Wen-Wen, ZOU Ying, SI You-Bin
2012, 28(5):  559-562. 
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An experiment was carried out on nanoscale zero-valent iron (NZVI) reducing Cr(Ⅵ) in water to explore effects of NZVI application rate, initial concentrations of Cr(Ⅵ), initial pHs, and organic acids on the reduction. It was found that NZVI efficiently reduced Cr(Ⅵ) in water at a rate 7 and 13 times higher than that of iron powder and filings, respectively. Under the condition of the initial concentration of Cr(Ⅵ) being 20 mg•L-1 and the NZVI application rate being 5g•L-1, the reduction rate reached 82% after 24 h of incubation. Low pH solution pH promoted corrosion of NZVI, which raised Cr(Ⅵ) reduction rate.The highest reduction rate occured in solution being 3.0 in pH. Among organic acids, oxalic acid, malonic acid and succinic acid all significantly improved the effect of NZVI reducing Cr(Ⅵ), and followed the order of oxalic acid > malonic acid > succinic acid.
Remediation of Contaminated Paddy Soil by Immobilization of Pollutants in the Diaojiang Catchment,Guangxi Province
WANG Lin, XU Ying-Ming, LIANG Xue-Feng, SUN Guo-Hong, SUN Yue-Bing, LIN Da-Song
2012, 28(5):  563-568. 
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Effects of sepiolite,lime and phosphate immoblizing cadmium and lead in contaminated paddy soil in the Diaojiang catchment,Guangxi were investigated through a field experiment,and mechanisms of the effects were analyzed through fractionation of the polluatants in the soil.Results show that the use of these amendments markedly increased yield of the crop,both grain and straw,to the greatest extent,by 25.4% and 28.3%,respectively.The effect of combined application of sepiolite and phosphate was the most significant.The application of these immobilizers significantly decreased Cd and Pb concentrations in all the parts of the plant.Especially in brown rice,the drop reached 65.12% and 61.86%,respectively.The effect of combined application of the immobilzers was more significant than that of the application of only one kind of immobilizer in the above-ground part of the plant.The brown rice produced in the treament of combined application of sepiolite and phosphate or lime met Maximum Levels of Contaminants in Foods(GB 2762-2005) in Cd concentration.The application of immobilizers,combined or single,significantly reduced the concentrations of TCLP-extractable Cd and Pb(TCLP,i.e. toxicity characteristic leaching procedure),with the maximal possible reduction reaching 28.86% and 45.60%,respectively.Combined application was obviously more effective than the application of only one.To sum up,combined application of sepiolite and phosphate is the most effective recommendation for remediation of Cd and Pb contaminated paddy soil by immobilizing the pollutants in Diaojiang catchment,Guangxi.
Use of a Modified Multi-Soil-Layering System to Remove Nitrogen From Polluted River Water
LI Sen, YE Hai, CHEN Xin, XUE Feng, WANG Tong-Cheng
2012, 28(5):  569-573. 
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To solve the problem that the MSL system can not efficiently remove TN from polluted river water because of inadequate denitrification therein, the system was modified by using solid carbon from non-water-soluble, biodegradable PBS and optimizing its spatial structure. To determine nitrogen-removal effect of the modified MSL system, an experiment was carried out to compare the modified one with an old one using sawdust carbon, showing that granular PBS carbon is much better in denitrification effect, thus raising the TN removal rate up to 64.3%, 20.6% peretage point higher than the one using sawdust carbon, and the optimization of the spatial structure of the system uplifted TN removel efficiency from 43.7% to 71.7%, Moreover, the system worked more smoothly and free of clogging. However, the modification did not have any obvious effect on removal of organic matter|, phosphorous and ammonia nitrogen.
Econiche of the Settlements in Mountains of the Upper Reaches of Min River and Its Mathematical Model
MA Xu, WANG Qing, DING Ming-Tao, LIU Yan-Guo
2012, 28(5):  574-578. 
Abstract ( 871 )   PDF (1684KB) ( 1948 )  
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Based on the basic theory of econiche, a concept of econiche of mountain settlement was proposed.The econiche of a mountain settlement may reflect spatial position of the settlement vertically along the mountain and resources space available to the settlement for sustenance, and meanwhile a mathematical model was established for calculating widths of the econiches of the 12 settlements in Shangxiameng Valley of the Zagunao Section of the Min River . Results show that in calculating widths of settlement niches, natural factors arewere the major ones to take into account, which arewere followed by economic and then social factors. Settlements with an elevation of 1900-2600m were 0.03 - 0,11 in econiche width and those with an elevation of >2600-3100m were 0.12-0.13, demonstrating that econiche width increasesd with elevation. The findings of the study may provide a new method for evaluating the relationship between people and land in mountainous regions and space planning of settlements.
Aquatic Ecor-Risk and Health Risk Assessment of Application of Pesticide in Rice Paddy in Dongtiaoxi Watershed Based on Modified RICEWQ-EXAMS Model
CHENG Yan, ZHOU Jun-Ying, SHAN Zheng-Jun
2012, 28(5):  579-586. 
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The scenario of exposure of paddy fields and surface water in Dongtiaoxi watershed was reconstructed for test of a modified RICEWQ-EXAMS model in aquatic eco-risk assessment and healthy risk assessment of the application of pesticides in rice paddy fields in Dongtiaoxi Watershed. RICEWQ-EXAMS model has been extensively adopted in assessment of exposure of paddy field-surface water in countries the world over. Now it is independently modified by the research group and tested in this project. Results show that among all the ten kinds of pesticides commonly used in paddy fields of this region, herbicide trifluralin showed a high risk of acute toxicity to green algae, insecticide endosulfan, both a high risk of acute toxicity and a risk of chronic toxicity to fish, avermectins a high risk of acute toxicity to daphnia, and hexaflumuron both a high risk of acute toxicity and a risk of chronic toxicity to daphnia, the other pesticides are quite low in risk of either acute or chronic toxicity to fish, daphnia and algiae. As to the healthy risk assessment of the 10 pesticides, identical conclusions are reached whether using the traditional method or the risk assessment model that the 10 pesticides do not pose risk to human health when used properly in paddy fields. The results of the assessment tally quite well with the actual situation. Therefore, it could be concluded that the develoed scenario and the modified model can quite effectively be used in risk assessment of the application of pesticides in paddy fields in Dongtiaoxi watershed.
Simultaneous Determination of Residues of Four Typical Categories of Veterinary Antibiotics in Organic Fertilizers
GE Feng, GUO Kun, TAN Li-Chao, DAI Yi-Jun
2012, 28(5):  587-594. 
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A new method using SPE-UPLC-MS/MS was developed to determine residues of four typical categories of veterinary antibiotics in organic manure. The method uses the solution composed of acetonitrile and phosphate buffer (pH=3) for extraction of organic manure samples, and the series of SAX and HLB to purify and enrich the extract. Methanol-φ=0.1% formic acid was chosen as carrier for liquid chromatographic analysis.  When the concentrations of the 18 antibiotics were in the range of 5-500µg•kg-1, they showed good linear relationships, with determination coefficients (r2) ≥ 0.99. When the mass concentration of the antibiotics was raised to the range of 50-500µg•kg-1, the recovery rates of sulfonamides, fluoroquinolones, tetracyclines and macrolides varied in the range from 71.6% to 94.3%, from 72.3% to 86.7%, from 71.0% to 102.2% and from 70.7% to 93.3%, respectively, with relative standard deviation varying in the range of from 2.1% to 11.4%. This method was applied to determine residues of veterinary antibiotics in organic fertilizers on sale in Nanjing. In addition to sulfonamides, others were also detected to a varying extent.
Simultaneous Determination of Cyromazine and Melamine in Green Vegetables With HPLC
LIU De-Jin, GE Feng, WU Ruo-Han, GAO Shi-Xiang
2012, 28(5):  595-598. 
Abstract ( 819 )   PDF (858KB) ( 1702 )  
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An analytical method has been developed for simultaneous determination of cyromazine and metabolite melamine in green vegetables using a high performance liquid chromatograph (HPLC) coupled with an ultraviolet detector. Fresh green vegetable samples were freeze-dried, homogenized and subjected to extraction in solution containing 95% methanol and 5% aqueous ammonia assisted with ultrasonics. The extracts were concentrated and purified through centrifugalization, rotary evaporation and solid phase extraction, and quantified using a high performance liquid chromatography-ultraviolet detector. It used an Agilent NH2 column as chromatographic column for separation, solution consisting of 90% acetonitrile and 10% water as carrier with a flow rate of 1 mL•min-1 and worked with a wavelength of 214 nm. It was found that the standard curves of cyromazine and melamine in the range of 0.05-10 mg•L-1 showed a good linear relationship with their peak areas with correlation coefficients not less than 0.9995,and the recovery rate of cyromazine and melamine at fortified levels of 0.2-4.0 mg•kg-1 varied in the range of 81.26%-87.69% and 78.24%-82.33% with relative standard deviation being 2.75%-6.18% and 3.99%-6.67%, respectively. The limit of quantification (LOQs) was 11.30 μg•kg-1 for cyromazine and 20.38 μg•kg-1 for melamine. This method is saimple, sensitive and suitable for determination of cyromazine and melamine in green vegetables.
Optimization of Policy and Management Service System on Control of Rural Non-Point Source Pollution—A Case Study of the Rural Area of Shanghai
HUANG Wen-Fang, SHEN Zhe
2012, 28(5):  599-604. 
Abstract ( 719 )   PDF (881KB) ( 2161 )  
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It is a common view that control of rural non-point source pollution is not only a technology problemissue, but also a management system issue. So hard currently it has become a hot spot and a hard nut as well to probe and consummate the policy, management and service system for control of rural non-point source pollution. Selecting the rural suburbs of Shanghai for case study, the status quo of the rural non-point source pollution and its management have been analyzed and summarized. While affirming the effect of the current work on pollution management, the authors try to discern limitations of the work are discerned and it was also pointed out that inharmony between the agriculture development policy and the environmental protection policy and the lag of the management mechanism and service system behind the change in the rural development model are the basic causes. To counter the major contributors of the rural non-point source pollution, i.e. chemical fertilizers, pesticides, livestock excretes and rural domestic sewage, countermeasures and suggestions are presented for management of the pollution from the aspects of modification of the agricultural subsidization system, reconfiguration and implementation of the rural multi-value system and consummation of agricultural production service system.
Experimental Study on Used Ceramsite From Wastewater Treatment as Culture Substrate
GUI He-Rong, PENG Wei-Hua, HE Wen-Li
2012, 28(5):  605-608. 
Abstract ( 678 )   PDF (923KB) ( 1665 )  
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Ceramsite(SSA=7.925 m2·g-1)made from fly ash and wheat straw is often used as filling in biological aerated filter(BAF)for treating municipal sewage and restaurant wastewater,enabling BAF to remove 90.33%,77.44%,82.41% and 86.50%,68.98%,80.30% of COD,NH3-N,and TP from two kinds of wastewater,respectively.How the used ceramsite from the system could be recycled as resource for agricultural use was once under feasibility study,which was aimed at exploring effects of its use on seed germination,growth,drought-resistance and yield of Brassica chinesis.Results show that the substance meets the standard for use of urban wastes in agriculture(GB8172-87).The treatment of 20% ceramsite in the culture substrate was the highest,reaching 100% within five days,in seed germination rate.The plant grew better with increasing content of ceramsite in the substrate,and its yield showed a rising trend,too.It increased by as high as 352.51%,when ceramsite reached 80% in the culture substrate.However,drought resistance of the substrate was negatively correlated withe the content of ceramsite,and the substrates with 20% and 40% of ceramsite were more capable of preserving soil moisture.