Journal of Environmental Sciences - Volume 13, issue 2

Authors: Chen, Bao-liang | Zhu, Li-zhong

Article Type: Research Article

Abstract: A series of organobentonites synthesized by exchanging organic cation such as dodecyltri-methylammonium (DTMA),benzyldimethyltetradecylammonium (BDTDA), cetyltrimethyl-ammonium (CTMA), octodeyltrimethylammonium (OTMA) on bentonite. The optimal condition, properties and mechanisms for the organobentonites to sorb phenanthrene, anthracene, naphthalene, acenaphthene in water were investigated in detail. The partition behavior was determined for four polycyclic aromatic hydrocarbons (PAHs), such as naphthalene, phenanthrene, anthracene and acenaphthene, from water to a series of organobentonites. The interlayer …spacings and organic carbon contents of organobentonites, removal rate and sorption capacities for organobentonites to treat phenanthrene,anthracene, naphthalene, acenaphthene were correlated to the length of alkyl chains and the amounts of cation surfactant exchanged on Foundation item: the bentonite. Phenanthrene, anthracene, naphthalene, and acenaphthene sorption to organobentonites were characterized by linear isotherms, indicating solute partition between water and the organic phase composed of the large alkyl functional groups of quaternary ammonium cations. PAHs distribution coefficients (K_d)between organobentonites and water were proportional to the organic carbon contents of organobentonites. However, the partition coefficients (K_oc) were nearly constants for PAHs in the system of organobentonite-water. The K_oc of phenanthrene, anthracene,naphthalene, acenaphthene were 2.621x10^5, 2.106x10^5, 2.247x10^4,5.085x10^4, respectively. The means K_oc values on the organobentonites are about ten to twenty times larger than the values on the soils/sediments, what is significant prerequisite for organobentonite to apply to remediation of pollution soil and groundwater. The sorption mechanism was also evaluated from octanol-water partition coefficients and aqueous solubility of PAHs. The correlations between lgK_oc and 1gk_ow, 1gK_oc and 1gS for PAHs in the system of water/organobenotonites are also discussed. Show more

Keywords: organobentonites, polycyclic aromatic hydrycarbons, partition

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 129-136, 2001

Authors: Liu, Wei-ping | Fang, Zhuo | Liu, Hui-jun | Yang, Wei-chun

Article Type: Research Article

Abstract: Adsorption and catalytic hydrolysis of the herbicide diethatyl-ethyl [N-chloroacetyl-N-(2,6-diethylphenyl)glycine ethyl ester] on homoionic Na^+-, K^+-, Ca²^+-, and Mg²^+-montmorillonite clays were investigated in water solution. The Freundlich adsorption coefficient, K_f, got from isotherms on clay followed the order of Na^+ ≈K^+ > Mg²^+ ≈Ca²^+. Analysis of FT-IR spectra of diethatyl-ethyl adsorbed on clay suggests probable bonding at the carboxyl and amide carbonyl groups of the herbicide. The rate of herbicide hydrolysis in homoionic …clay suspensions followed the same order as that for adsorption, indicating that adsorption may have preceded and thus caused hydrolysis. Preliminary product identification showed that hydrolysis occurred via nucleophilic substitution at the carboxyl carbon, causing the cleavage of the ester bond and formation of diethatyl and its dechlorinated derivative, and at the amide carbon, yielding an ethyl ester derivative and its acid.These pathways also suggest that hydrolysis of diethatyl-ethyl was catalyzed by adsorption on the clay surface. Show more

Keywords: adsorption, montmorillonite, diethatyl-ethyl, diethatyl, catalytic hydrolysis

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 137-142, 2001

Authors: Bharati, V. R. | Khan, R. N. | Kalavati, C. | Raman, A. V.

Article Type: Research Article

Abstract: A field study was conducted to evaluate the protozoan colonization patterns on artificial substrates in relation to organic pollution within a tropical harbour. The composition of protozoans and their succession rates on artificial substrates(polyurethane foam units) were compared between two field stations(A and B), and their presence were considered with regards to the prevailing water quality conditions at the study sites. Altogether 44 genera of flagellates and ciliates were documented. The common genera of flagellates and …ciliates were documented. The common genera of flagellates encountered included Monas, Polytoma,and Chromalina. Among the ciliates, the predominant genera were Tetrahymena, Vorticella, Lagynophyra, and Heloiphyra. These groups exhibited characteristic successional patterns in relation to ambient water quality. At Station A, located close to the sewage outfall, the water quality parameters included poor Secchi-disc transparency(0.48m), dissolved oxygen of 1.93 mg/ml, salinity of 18 psu, and temperature 31.3 ºC. Here, thenanoflagellates(spumella)colonized first, followed by microcilliate(Tetrahymena) and sessile form(Vorticella). Station B, located on the seaward side, was characterized by relatively less-stressed environmental conditions with transparency 1.85m and dissolved oxygen value of 6.04 mg/ml. Salinity of 27.27 psu, and mean temperature of 30 ºC were recorded at "B". At this station, the nanoflagellate Polytoma was first documented to colonize on the substrate, followed by microcilliate(Lagynophra) and suctorid(Heliophyra). These findings support the use of protozoans as indicator species for evaluating the hazards posed by organic pollution to natural estuarine communities. Show more

Keywords: adsorption, montmorillonite, diethatyl-ethyl, diethatyl, hydrolysis, catalytic

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 143-147, 2001

Authors: Ye, Chang-ming | Gong, Ai-jun | Wang, Xing-jun | Zheng, He-hui | Lei, Zhi-fang

Article Type: Research Article

Abstract: In this paper, the concentration distribution and environmental fate of atrazine in a crop-soil-groundwater system at Baiyangdian Lake area of North China were studied. The concentration of the herbicide in spatial and vertical soils, and in roots, stem, leaf, corncob and kernel of corn, and in groundwater were measured by HPLC. The results showed that the variation of spatial concentration of atrazine in soil can be described by first-order kinetics equation which has a half-life of …360 days and a rate constant of 0.0019d^-¹. The vertical variation of atrazine concentration with soil depth follows the exponential decay law. After 120 days following atrazine application, the mass distributions of this herbicide in crop-soil-groundwater system are 71% in soil, 20% in groundwater and 1% in crop respectively, and 8% due to loss by degradation or often removal processes. The order of atrazine concentration in every part of corn crop is in roots>in corncob>in kernel of corn>in leaf. Show more

Keywords: atrazine, soil, corn crop, groundwater, fate, China

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 148-152, 2001

Authors: Zhou, Dong-mei | Wang, Shen-qiang | Chen, Huai-man

Article Type: Research Article

Abstract: Adsorption and desorption process of cadmium in red soil(Ferrisols) as well as the influence by media's pH were investigated in detail with and without citric acid and EDTA. Experimental results clearly showed that Cd adsorption in red soil was affected significantly by the coexisted organic chemicals. In the presence of citric acid and EDTA, Cd adsorption in red soil increased with pH in acid media but decreased in high pH one. Further studies placed stress on …the adsorbed Cd in red soil which was found to be existed mainly as exchangeable one at pH<5.5, and desorption rate by 0.10 mol/L NaNO_3 gave a peak-shaped curve due to the difference of specifically and nonspecifically adsorbed Cd with pH's change. Show more

Keywords: cadmium, interaction, organic acid, red soil

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 153-156, 2001

Authors: Wu, Zhi-chao | Zeng, Ping | Wang, Shi-feng | Gao, Ting-yao

Article Type: Research Article

Abstract: The wastewater treatment from brassylic acid manufacturing plant using membrane bioreactor (MBR) was studied. The membrane bioreactor consisted of batch-operation biological aeration tank and ultrafiltration evaluation tank. The content of test included the affection of variation operation conditions on ultrafiltration separation, the general characteristics of MBR process, and the difference comparing with the conventional biological treatment. The results are as follows: (1) among the test membrane material, polyether sulphone (PES) membrane is …more suitable for the wastewater treatment; (2) when the cutoff molecular weight is among 10000-50000, the higher the cutoff molecular weight, the bigger the water flux is in the test; (3) under the operation pressure, water flux increases accompanying with the increasing of operation pressure; (4) the paper filtered COD concentration has more affection on the water flux than the suspended solid concentration; (5) as the volume loading of MBR increases, the accumulation of high molecule organic substance and colloid increases, the membrane permeate COD concentration and paper filtered COD concentration increase too, meanwhile the water flux reduces; (6) when the sludge retention time of activated sludge of MBR increases, the accumulation of high molecule organic substance and colloid reduces, the membrane permeate COD concentration and paper filtered COD concentration reduce too, and the water flux increases; (7) comparing with the conventional biological process, the microbial activity is higher, but the microbial species is less. Show more

Keywords: membranae bioreactor, biological treatment, brassylic acid wastewater

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 157-163, 2001

Authors: Mungai, D. N. | Coulson, C. L. | Stigter, C. J. | Ng'ang'a, J. K. | Mugendi, D. N.

Article Type: Research Article

Abstract: Alley cropping of Cassia siamea and maize was studied in semi-arid Kenya for soil fertility improvement. Katumani composite maize was planted except in the short rains of 1988 (SR88) when a hybrid variety was sown. Therefore the grain yield per row increased differently in the alley cropped maize (CM). Sole maize (SM) and CM yields were higher in SR88 than in the long rains of 1988 (LR88) by 62% and 38%, while yields from the same treatments in …LR89 were only 21% and 45% of those in SR88. These differences in relative maize yields are attributed to differences between the two maize varieties in competition under nutrient stress conditions. Show more

Keywords: alley cropping, Cassia siamea, maize nutrients, semi-arid condition, soil moisture, Kenya, maize yield

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 164-169, 2001

Authors: Liu, Jian-guo | Nie, Yong-feng

Article Type: Research Article

Abstract: Fractal approach is used to derive a power law relation between effective diffusion coefficient of solute in porous media and the geometry parameter characterizing the media. The results are consistent with the empirical equations analogous to Archie'slaw and are expected to be applied to prediction of effective diffusion coefficient.

Keywords: diffusion, porous media, fractal, effective diffusion coefficient

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 170-172, 2001

Authors: Wu, Gang | Li, Jing | Kong, Hong-mei | Zhao, Jing-zhu | Gao, Lin

Article Type: Research Article

Abstract: This paper studied the distribution and utilization status, reasonable exploitation patterns and potential productivity, and sustainable development of marginal lands in the Three Gorge Reservoir Areas. It has been pointed that problems of the soil fertility degradation, poor productivity in crop lands, natural disasters and environmental deterioration existed in all the exploited marginal lands. In order to maintain the sustainability of the marginal lands, following measure have been proposed: prohibiting cultivation in …the crop lands with a slope more than 25º, restoring vegetation in the slope more than 25º, strengthening the basic agricultural construction, establishing the production base of woody feeds and oils, establishing a multi-dimensional management model with reasonable structure and optimumfunction for forestry, agriculture and fishing. Show more

Keywords: marginal lands, Three Gorge Reservoir Area, sustainable development, utilization pattern

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 173-179, 2001

Authors: Wang, Jin-sheng | Yang, Zhi-feng | Li, Shu-shen | Wang, Zhi-ming

Article Type: Research Article

Abstract: The radionuclide migration from a certain Chinese repository with low-intermediate level radioactive solid waste is studied. The migration in groundwater is analyzed and computed in detail. Under presumption of normal releasing, or the bottom of the repository has been marinated for one month with precipitation reaching 600 mm once and a 6m aerated zone exists, a prediction for 7 radionuclides is conducted. It shows that the aerated zone is the primary barrier for migration. The migration …for radionuclides ^60Co, ^137Cs, ^90Sr, ^63Ni, etc. will be retarded in it within 500 years. The concentration of ^239Pu will be decreased by amount of 6 order. Only ³H and ^14C can migrate through the aerated zone. The radionuclides that go through the aerated zone and enter the aquifer will exist in spring, stream and sea. Based on this, the intake dose by residents in different age group resulting from drinking contaminated spring water, eating seafood is calculated. The results showed that the impact of the repository to the key resident group is lower than the limit in national repository regulation standard. This complies with the repository management target. Show more

Keywords: prediction of environmental impact, numerical calculation, nuclide, low-intermediate level radioactive waste disposal

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 180-184, 2001

Authors: Tian, Wen-dong | Wei, Xiao-lin | Li, Jun | Sheng, Hong-zhi

Article Type: Research Article

Abstract: The internal circulating fluidized bed (ICFB) system is characterized with fast combustion, low emission, uniformity of bed temperature and controllability of combustion process. It is a kind of novel clean combustion system, especially for the low-grade fuels, such as municipal solid waste(MSW). The experimental systems of ICFB with and without combustion were designed and set up in this paper. A series of experiments were carried out for further understanding combustion process and characteristics of several design …parameters for MSW. Based on the results, a design routine for the ICFB system was suggested for the calculation of energy balance, airflow rate, heat transfer rate, and geometry arrangement. A test system with ICFB combustor has been set up and the test results show that the design of the ICFB system is successful. Show more

Keywords: fluidized bed, ICFB, combustion, MSW

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 185-188, 2001

Authors: Deng, Yi-xiang | Chen, Ji-ning | Hu, Xue-tao

Article Type: Research Article

Abstract: MAGIC is one of the most widely used models for forecasting long-term acidification. The model's code, however, has been experiencing numerical instability, though this might not be widely known to the public users. The major instability comes from the analytical solution to two cubic equations for calculating SO_4²^-concentration and the exchangeable fraction of Al on the soils. The mathematical algorithm for calculating the concentration of SO_4²^- from a quadratic equation is also found instable. …This paper is aimed at improving the instability above through proved numericalalgorithms. Show more

Keywords: numerical instability, MAGIC model

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 189-191, 2001

Authors: You, Song-cai

Article Type: Research Article

Abstract: This paper presents the study on agriculture adaptation to climate change by adopting the assumed land use change strategy to resist the water shortage and to build the capacity to adapt the expected climate change in the northern China. The cost-benefit analysis result shows that assumed land use change from high water consuming rice cultivation to other crops is very effective. Over 7 billions m³ of water can be saved. Potential conflicts between different social interest …groups, different regions, demand and supply, and present and future interests have been analyzed for to form a policy to implement the adaptation strategy. Trade, usually taken as one of adaptation strategies, was suggested as a policy option for to support land use change, which not only meets the consumption demand, but also, in terms of resources, imports waterresources. Show more

Keywords: agriculture, adaptation, climate change, land use change

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 192-197, 2001

Authors: PU, Jiang-ping | PU, Pei-min | HU, Chun-hua | QIANG, Jun-ling | PU, Jue-xing | HUA, Ji-kang

Article Type: Research Article

Abstract: A new technology for harnessing the dye polluted water and dye collection was developed. It is based on the enhanced evaporation by using solar, wind, and air temperature energy and additional heat-electric energy. It consists of four parts: (1) evaporation carrier system (evaporation carrier and frame for evaporation carrier) for polluted water; (2) polluted water circulating system (pumping-spraying-collecting); (3) heating system; (4) workshop with polluted water reservoir-tanks and rainfall prevention roof. The …polluted water was (heated in case necessary) sprayed to the evaporation carrier system and the water was evaporated when it moved in the space and downward along the carrier mainly by using natural (solar, wind, and air temperature energy). In case, when there is no roof for the carrier system, thepolluted water can be stored in the reservoirs (storage volume for about 20 days). The first 10-25 mm rainfall also need to be stored in the reservoirs to meet the state standard for discharging wastewater. The dye may be collected at the surface in the reservoir-tanks and the crystallized salt may be collected at the bottom plate. The black-color wastewater released by the factory is no more discharged to the surface water system of Taihu Lake Basin. About 2 kg dye and 200 kg industrial salt may be collected from each tone of the polluted water. The non-pollution production of dye may be realized by using this technology with environmental, economical and social benefits. Show more

Keywords: dye polluted water harnessing, dye collection technology

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 198-200, 2001

Authors: Gu, Guo-bang | Huang, Guo-feng | Li, Xin-jun | Wan, Hong-fu | Li, Fang-bai

Article Type: Research Article

Abstract: The gold ion modified TiO_2 was prepared by means of sol-gel whereas gold deposited TiO_2 was prepared by means of photo- reduction. The physical properties were influenced significantly by the presence of gold ion or gold. The enhanced photo-activity of gold modified TiO_2 was quantified in terms of methylene blue degradation. The presence of gold ion in TiO_2 lattices or gold on TiO_2 surface enhanced their photo-activity. The optimum molar content of gold ion doping and …gold deposition all was 0.5%. The first-order rates constants of gold modified TiO_2 was more than that of pure TiO_2, and decreased by increasing the content of gold ion and gold when their contents were more than 0.5%. Gold iondoped in TiO_2 lattices was more effective to enhance the photo-activity than gold on TiO_2 surface. Moreover, the relationship between physical properties, chemical properties and photo-activity has been discussed. Show more

Keywords: gold modification, titanium dioxide, photo-catalysis, methylene

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 201-204, 2001

Authors: Yang, Jian-xin | Nielsen, Per H.

Article Type: Research Article

Abstract: The methodological basis and procedures for determination of Chinese normalization references and weighting factors according to the EDIP-method is described. According to Chinese industrial development intensity and population density, China was divided into three regions and the normalization references for each region were calculated on the basis of an inventory of all of the region's environmental emissions in 1990. The normalization reference was determined as the total environmental impact potential for the area in question …in 1990(EP(j)_90) divided by the population. The weighting factor was determined as the normalization reference (ER(j)_90) divided by society's target contribution in the year 2000 based on Chinese political reduction plans, ER(j)_T2000.). This paper pressents and discuss results obtained for eight different environmental impact categories relevant for China:global warming,hazardous waste and slag and ashes. Show more

Keywords: life cycle, impact assessment factors, China

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 205-209, 2001

Authors: Fang, Zhan-qiang | Cheung, R. Y. H. | Wong, M. H.

Article Type: Research Article

Abstract: Molluscs are able to accumulate heavy metals and impose health hazard to consumers. The main objective of the present study is to investigate the heavy metal concentrations in edible bivalves and gastropods available in major markets of the Pearl River Delta. Fourteen species of edible molluscs were purchased from six markets in Hong Kong and Guangdong Province. The fresh of these biota were tested for their cadmium (Cd), copper (Cu), zinc (Zn), lead (Pb), nickel (Ni), …chromium (Cr), antimony (Sb) and tin (Sn)concentrations (based on wet weight). The results indicated that amongst the 14 edible molluscs, only Cd, Pb, Ni, Cr, Sb and Sn concentrations in three species(Ruditapes philippinarum, Perna viridis and Hemifusus tuba) were within the local regulatory limits. Over 60% of bivalve species exceeded maximum permitted levels of Cd (2 µg/g) and Cr (1 µg/g), while over 40% of gastropod species exceeded the maximum levels of Sb (1 µg/g) and Cr(1 µg/g). Most of the samples collected from Hong Kong had significantly higher contents of Pb and Sb, but similar levels of Cd, Cu and Zn when compared with samples collected across the border (p<0.5; p<0.01; p<0.001 respectively). In general, the molluscs purchased in Guangdong markets had higher metal contents than those purchased from the Hong Kong markets. When compared with the Provisional Tolerable Weekly Intake or Maximum Acceptable Daily Load recommended by FAO/WHO Expert Committee on Food Additives, Cd levels of five species (Anadara ferruginea, Pinna pectinata, Chlamys nobilis, Babylonia lutosa and Hemifusus terntanus) and Cr levels of seven species (Anadara ferruginea, Paphia undulata, Pinna pectinata, Babylonia lutosa, Hemifusus terntanus, Cymbium melo and Cipangopaludina chinensis) were higher than both the human daily acceptable limits (for Cd and Cr respectively) and the local regulatory levels (for Cd and Cr respectively). Show more

Keywords: Heavy metals, edible molluscs, human health, Pearl River Delta

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 210-217, 2001

Authors: Khan, M. A.

Article Type: Research Article

Abstract: In arid zone of Rajasthan, India, nearly 21900 hm² area along Bandi River has been affected by industrial effluent discharge into the river bed. Analysis of groundwater samples collected from these sites revealed that area at the vicinity of the river is most affected. The effluent water in the river is the main source of contamination of ground water. Concentration of sodium and chloride has been higher with proportional increase in TDS and EC value in …the area within zone A (river water), zone B(0-100m), zone C (101-250m), zone D (251-500m) and zone E (501-1000m). There is decreasing trend in ion concentration from zone A to zone E and F, reflecting reduced effect of effluents. The pollution of water resources has resulted in the degradation of other natural resources such as land, soil and vegetation. Nearly 4463 hm² (20.38%) area has been very severely affected. EC value at places exceeds 20 dS/m. Soil and land have become hard, compact and saline. Cropping intensity has declined. In the area (3633 hm²)affected severely, the EC value of water varies from 10-20 dS/m.Irrigation with such water has created problem of salinity, sodicity in soils. Herbal biomass declined considerably. Double cropping has almost stopped. Almost 8494 hm² area is affected moderately. EC of ground water varies form 5 to 10 dS/m. Fragile surface crust, declining trend of phosphorous and potassium in the soil, poor density of natural vegetation are significant manifestations. Apart from this, 5305 hm² area is slightly affected. Show more

Keywords: pollution, water resources, industrialization, arid zone, India

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 218-223, 2001

Authors: Sheng, Xue-bin | Sun, Jian-zhong | Liu, Yun-xia | Feng, Jiang-bin

Article Type: Research Article

Abstract: The Bashang region is a typical vulnerable eco-environmental zone. Our analysis of paleodunes, paleosol profiles, and lake changes taking place during last ten thousands years indicated that:(1) 10-6.9 ka B.P. was a post-glacial temperature-increasing stage, in which lakes had their high water level; (2) 6.9-3.0 ka B. P. was a large warm stage, during which four paleosol layers were developed and climate fluctuation has assumed 4-5 small cold-humid and cold-dry alternations. Since 5.4 ka B.P, the …lakes tended to gradually shrink; and by 2.1 ka B.P., water level has fallen by 2.7 m; (3) since 3.0 ka B. P. a general trend of the region was to change into a dry, warm-dry and cold-dry environment. Show more

Keywords: Bashang region, environmental change

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 224-227, 2001

Authors: Liu, Dong-hua | Jang, Wu-sheng | Hou, Wen-qiang

Article Type: Research Article

Abstract: The effects of different concentrations of copper sulfate on root and shoot growth of maize(Zea mays L.) and the uptake and accumulation of Cu²^+ by its roots and shoots were investigated in the present study. The concentrations of opper sulfate (CuSO_4·5H_2O) used were in the range of 10^-^5-10^-³mol/L. Root growth decreased progressively with increasing concentration of Cu²^+ in solution. The seedlings exposed to 10^-³ mol/L Cu²^+ exhibited substantial growth reduction, yielding only 68% of …the root length of the control. The shoot growth of the seedlings grown at 10^-^5-10^-^4 mol/L Cu²^+ were more or less than the same as the control seedlings. The leaves treated with 10^-³ mol/L Cu²^+ were obviously inhibited in shoot growth. The fresh and dry weights both in roots and shots decreased progressively with increasing Cu²^+ concentration.This fits well with the above mentioned effects of copper sulfate on root growth. Zea mays has considerable ability to remove Cu from solutions and accumulate it. The Cu content in roots of Z. Mays increased with increasing solution concentration of Cu²^+. The amount of Cu in roots of plants treated with 10^-³, 10^-^4 and 10^-^5 mol/L Cu²^+ were 10, 8 and 1.5 fold, respectively, greater than that of roots of control plant. However, the plants transported and concentrated only a small amount of Cu in their shoots. Show more

Keywords: Zea mays L., uptake, accumulation, Cu²^+

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 228-232, 2001

Authors: Jin, Ming-hong | Feng, Zong-wei | Zhang, Fu-zhu

Article Type: Research Article

Abstract: The impacts of different O_3 concentration on the biomass and yield of rice were studied by using OTC-1 open-top chambers. Experimental treatments included the activated charcoal-filtered air (CFA), 50nl/L (CF50), 100nl/L (CF100) and 200nl/L (CF200) concentrations of O_3. The O_3 treatments significantly decreased the total biomass per plant. The elevated O_3 exposure resulted in a more decrease in the root growth than in the shoot growth. Assessments of yield characteristics at the final harvest revealed an …O_3 - induced decrease in the number of grains per plant, resulting from fewer ears per plant, fewer grains per ear and more unfilled grains per ear. The 1000 grain dry weight and the harvest index (HI) were not changed significantly under 50nL/L or 100nL/L O_3 exposure, but reduced by 17.0% and 4.8% by 200nL/L O_3 treatment, respectively. Compared to the CFA treatment, CF50, CF100 and CF200 treatments caused a 8.2%, 26.1%, 49.1% decrease of the grain yield per plant, and a 14.2%, 31.7%, 51.7% decrease of the total biomass per plant, respectively. Linear regression showed that the 7h-daily mean O_3 concentration exposure for 3 months (July-September) and AOT40 (cumulative exposure accumulation over threshold 40 nL/L) were well correlated with the relative grain yield. A yield loss of 10% was estimated to be at 46.9nl/L O_3 for 7h-daily mean O3 concentration exposure or at 12930 nl/(L·h )O3 for AOT40. Show more

Keywords: open-top chambers, ozone, rice, growth, yield, biomass

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 232-236, 2001

Authors: CHENG, Zhi-jiu | YIN, Guang-jin | YANG, Li-qin | WANG, Wei | CHENG, Dan-dan

Article Type: Research Article

Abstract: The treatment of coking residual ammonia water has been a big difficult problem at home and abroad, and there is no breakthrough research achievement in the past. The invention patent "The method of treating all coking wastewater or treating coking residual ammonia water by flue gas" has been successfully used in Huaian Steel Works for high concentration and organic industry wastewater treatment. Not only can it realize the wastewater zero discharge, but also the wastewater treatment …has an effect of de-sulfur and de-nitrogen for flue gas. So that the flue gas exhaustcan meet the requirement of emission standard. The mass transfer and heat transfer, fly ash absorption and coagulation, acid and alkali neutralization reaction, catalysis oxidation and reduction reaction in flue gas would be the major factors. Show more

Keywords: flue gas, de-nitrogen, de-sulfur, zero discharge, coking residual ammonia water

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 237-246, 2001

Authors: Shang, Zong-Bo | Gao, Qiong | Yang, Dian-An | Yang, Zheng-Yu

Article Type: Research Article

Abstract: Information ecology is a new research area of modern ecology. Here describes spatial distribution analysis methods of four sorts of climatic variables, i.e. temperature, precipitation, relative humidity and sunshine fraction on Northeast China. First,Digital terrain models was built with large-scale maps and vector data. Then trend surface analysis and interpolation method were used to analyze the spatial distribution of these four kinds of climatic variables at three temporal scale: (1) monthly data; (2)mean monthly …data of thirty years, and (3) mean annual data of thirty years. Ecological information system were used for graphics analysis on the spatial distribution of these climate variables. Show more

Keywords: spatial distribution analysis, information ecology, trend surface analysis, climate variables

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 247-251, 2001

Authors: Qiao, Bing

Article Type: Research Article

Abstract: The paper introduces systematically the developing principle of CWCM 1.0 oil spill model based on Lagrange system and oil spill fate processes in environment, reviews two oil spill incidents of "East Ambassador" in Jiaozhou Bay and "Min Fuel 2" in the mouth of Pearl River, and designs the predict system simulating oil spill applied in contingency plans. It is indicated that CWCM 1.0 has met preliminarily the demands for functions of precision simulating and oil spill …predicting, and can plan an important role to support oil spill response. Show more

Keywords: oil spill model, emergy response, simulating and predicting system, Jiaozhou Bay, mouth of Pearl River

Citation: Journal of Environmental Sciences, vol. 13, no. 2, pp. 252-256, 2001