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Through selective enriched culture, a phenanthrene-degrading bacterial strain was isolated from the oil-contaminated soil in Shenfu irrigation area of Shenyang, Northeast China. The morphological and physiological-biochemical identification, 16S rDNA sequence analysis, and phylogenetic study showed that this strain was belonged to genus Acinetobacter and named as Acinetobacter sp. L2, and closest to Acinetobacter sp. DG880 [AY258108]. It could use phenanthrene as the sole carbon source. After 7 days culture, the degradation rate of phenanthrene was 96.3%. According to the activity of catechol 2,3-dioxygenase, the strain probably had phenanthrene-degrading genes.

By using microcosm culture method, this paper studied the dynamic changes of acetochlor degradation by earthworm in phaeozem with methamidophos or copper addition, aimed to approach the feasibility of using earthworm to intensify the detoxification of acetochlor. The results showed that the dynamics of acetochlor degradation accorded with the first-order reaction kinetics, whether earthworm existed or not. The activities of earthworm accelerated the detoxification of acetochlor, and the coexistence of methamidophos or copper with acetochlor evidently inhibited the degradation of acetochlor. The coexistence of methamidophos and acetochlor or of copper and higher concentration acetochlor altered the dynamics of acetochlor degradation, while the coexistence of copper and lower concentration acetochlor didn't have any obvious effect on the detoxification of acetochlor.

To make a comprehensive assessment on monosodium glutamate wastewater pollution, a pollution exposure experiment was carried out on the seed germination and root elongation of wheat, Chinese cabbage and tomato by using the wastewater discharged from different processing phases of monosodium glutamate production. The results showed that there were significantly positive linear relationships between the inhibition rates of wheat seed germination and root elongation and the COD(Cr) of mother liquor scraps. The toxicity of monosodium glutamate wastewater to the test crops was in the order of tomatoChinese cabbagewheat, indicating that tomato was most sensitive to the wastewater, and could be considered as an ideal toxic bioindicator. The half-effect concentration (IC50) based on the seed germination and root elongation of test crops exposed to the wastewater discharged from various processing phases of monosodium glutamate production was 22.0 to approximately 32432 mg x L(-1) and 17.3 to approximately 3320 mg x L(-1), respectively.

Chemicals in the environment often exist as mixtures and at low doses, whose ecotoxicological diagnosis and risk assessment are hard to be done with the help of the research results on the ecotoxicity of high-level exposure of single chemicals. This paper reviewed the research advances in ecotoxicology and risk assessment of low-dose chemical mixture contamination, with the focus on the molecular toxicological methods and the risk assessment approaches and schemes of simple and complex mixtures. Comments were given on the development directions of low-dose chemical mixture research, including the necessity of searching for sensitive endpoints, involving the approaches of other disciplines, increasing data accumulation, and setting up a comprehensive and identical risk assessment system.

The study on the absorption and accumulation of heavy metals lead, zinc, copper and cadmium by 8 plant species around a smelter showed that the metals accumulation by plants differed with plant species, their parts, and kinds of metals. Abutilon theophrasti had a higher capability of absorbing and accumulating Pb, Conyza canadensis, Ambrosia trifida, Polygonumn lapathifolium, A. theophrasti, Solanum nigrum, Chenopodium acuminatum and Helianthus tuberosus had a higher capability of absorbing and accumulating Zn, C. acuminatunz and A. theophrasti had a higher capability of absorbing and accumulating Cu, and S. nigrum, C. acuminatum, A. theophrasti, P. lapathifolium and C. canadensis had a higher capability of absorbing and accumulating Cd. These plants had TF values higher than 1, and were suitable for phytoextraction to remedy polluted soil. As for the plants with TF values lower than 1, they were suitable as the phytostabilizers of heavy metals-contaminated lands.

Nereis diversicolor is an ecologically keystone species of invertebrate that lives in the mud of marine-terrestrial interlaced zone. This species can accumulate a large number of toxic heavy metals such as copper, cadmium and zinc in its body, and thus, shows a high endurance against toxic heavy metals. This paper summarized the latest research advance at home and abroad in the characteristics and mechanisms of N. diversicolor endurance against heavy metals and organic contaminants. N. diversicolor could achieve its heavy metals- endurance through several eco-chemical processes, e.g., mucus secretion and contaminants excretion. The former could form a protective layer or integrate with dissolved ions of pollutants, and thus, decrease the bioavailability of pollutants, while the latter could lessen the pollutants' bio-toxicity. More researches believe that the toxic heavy metals in N. diverdicolor body are stored in non-toxic physicochemical forms, i. e., bound to metal-binding protein, such as metallothionein (MTs), metallothionein-like proteins (MTLP) and cytosolic heat-stable thiolic compounds (CHSTC), or incorporated into insoluble deposits or granules. The pivots of future researches on the ecotoxicology of N. diversicolor and its endurance mechanisms against pollutants were proposed.

With the rapid development of remediation technology for contaminated soils in China, remediation standard has become a bottleneck in judging the effects of this technology. In this paper, some suggestions on the establishment of remediation standards for contaminated soils, e.g., choice of contaminants, methods of detection, classification of contaminated soils, protection of groundwater, and assessment of toxicological risks were put forward, based on the analysis of the disadvantages of Soil Environmental Quality Standard.

The study on the thermodynamics and kinetics of Cd2+ adsorption in phaeozem and burozem showed that within the test range, Cd2+ adsorption was increased with its increasing initial concentration, and phaeozem had a much higher Cd2+ adsorption capacity than burozem. When the Cd2+ concentration in adsorption equilibrium was 20 mg x kg(-1), the amount of adsorbed Cd2+ was 1 485.2 mg x kg(-1) in phaeozem, but 700.6 mg x kg(-1) in burozem. The adsorption isotherm of Cd2+ in the two soils could significantly conform to Langmuir, Freundlich and Henry equations, while Temkin equation was not applicable to describe the isothermal adsorption process of Cd2+ in phaeozem and burozem. The maximum adsorption of Cd2+ in phaeozem and burozem was 5939.3 and 2 790 mg x kg(-1), respectively, according to Langmuir formulation. The Cd2+ adsorption in test soils was a rapid reaction, with 90% of Cd2+ adsorption in the first 2 min and reached equilibrium in 15-30 min. First-order dynamic equation was the optimal model to describe the kinetics of Cd2+ adsorption, while the other models in point were Elovich and Two-constant equations. The adsorption rate of Cd2+ in test soils was increased with its increasing initial concentration, but decreased with its increasing adsorbed amount. Under low concentrations of Cd2+, the decrease of its adsorption rate with time was more quickly in phaeozem than in burozem.

By the terrestrial ecotoxicological methods of seed germination and root elongation, and with aluminum-based coagulant AlCl3 which was widely used in wastewater- and water treatment as an example, this work studied the toxicological effects of aluminum-based coagulants on representative crops, including radish Raphanus sativus, cabbage Brassica chinensis and wheat Triticum aestivum, over a range of exposure concentrations under the neutral condition (pH= 7.0), with contrast to an acid condition (pH= 4.00). The results indicated that there was a significantly positive correlation between the concentration of AlCl3 and the inhibitory rate of root elongation and seed germination either under pH 7.0 or 4.0 (P0.01). Cabbage and wheat was more susceptive to AlCl3 toxicity under acid than under neutral condition, while radish was in adverse. The minimum inhibitory concentration of AlCl3 (2.0 mg x L(-1)) was lower under neutral than under acid condition.

With plastic rhizobox system, this paper studied the degradation behavior of methamidophos in the rhizosphere and non-rhizosphere of phaiozem and burozem planted with soybean. The results suggested that methamidophos could be rapidly decomposed in soil environment despite its higher acute toxicity, and its residual amount in phaiozem was generally below the level in burozem under same condition. In the absence of soybean (control), the residual amount of methamidophos at the 2nd day of incubation was about 33% in burozem, whereas only about 26% in phaiozem. An accelerated degradation of methamidophos in soybean rhizospheric soil was observed, especially in phaiozem. At the 9th day of incubation, the insecticide residue in the middle rhizobox phaiozem and burozem with soybean was decreased by 87.5% and 76.0%, respectively, compared with that of the control. The degradation process of methamidophos in soil environment followed the first-order equation, and its half-life was about 2 days.

Many active substances such as organic acids and enzymes excreted by living plant roots could induce a great difference of Eh and pH values between root-soil interface and non-rhizosphere soil, forming a special root-soil interface miniature environment. As a mini-type ecological area with most frequent exchanges of substances, root-soil interface plays a crucial role in their absorption, transformation, migration and eco-toxicological effects. In this paper, the eco-chemical behaviors of Cd in root-soil interface affected by the change of pH, Eh and root secretion, and its eco-toxicological effects on microorganisms and enzymes in root-soil interface were reviewed, based on the related research advances in recent decade. The shortages in relevant fields were pointed out, and the scientific problems to be researched in the future were suggested.

Water-treatment flocculants are being developed from traditional to inorganic, from inorganic to organic, from natural organic to synthetic organic, from synthetic organic to modified natural organic, from inorganic or organic to inorganic-organic, and from chemical to biological with ecological safety. In order to promote the rapid development and practical application of water-treatment flocculants, the research progress and application situation of flocculants for water treatment at home and abroad were reviewed. In particular, the characteristics of two important flocculant types, chemical and microbiological flocculants, as well as their application processes in water treatment were summarized, their development orientations were analyzed and evaluated, and the future research directions aimed to overcome the current shortages in developing and applying flocculants in China were put forward.

Environmental pollution and its solicitation in ecological problems of old industrial and mining areas have become a worldwide technological puzzle restricting sustainable economic and social development. But, the definition and category of old industrial and mining areas is still disputed as an important concept. In this paper, the concept of old industrial and mining area was discussed in theory, and, proceeded with analyzing the complexity of current situation and environmental pollution problems of old industrial and mining areas in China, more keystone attention was paid to the secondary pollution problems from old industrial and mining areas as an important frontier of science. On the basis of expounding the complexity and characters of environmental pollution in old industrial and mining areas, it was suggested that as two key scientific problems in environmental sciences and ecology, the formation mechanisms and control technology of secondary pollution in old industrial and mining areas and the responses of new-type diseases to environmental pollution based on molecular ecotoxicology should be systematically studied on the national scale, and be an important component of environmental protection strategy in China in the future.

By the methods of systematic ecology, and that of Simpson's biodiversity indices in particular, this paper quantitatively analyzed the ecological effects of ten years land use changes in a small town with rapid rural urbanization of Shaoxing County, Zhejiang Province, aimed to provide a scientific basis for healthy development of towns and small cities in China. The results showed that owing to the changes of land use functions, the biodiversity of green plants and soil microorganisms was obviously decreased, and the local climate conditions deteriorated, which was represented by the increase of annual mean air temperature and the decrease of annual mean relative humidity in this town. It was suggested that the long-term ecological changes in biodiversity should be considered in land use with rural urbanization.

Polybrominated diphenyl ethers (PBDEs) are a group of new type organic pollutants with significant ecological risk. As flame retardants, they have been increasingly added to industrial products, and thus, resulted in more and more extensive pollution of air, water, sediment and soil as well as their relevant ecosystems. In view of the new environmental problem and based on limited available data, this paper approached the anthropogenic sources of PBDEs and their pathways of environmental exposure, and gave the possible occurrence and concentration of PBDEs in several living organisms and different human tissues. The toxic effects and ecological influences of PBDEs acting on animals and human beings, and their potential biological accumulation and magnification in ecosystems were analyzed in the aspects of hypothyroid, neurotoxicity, and reproductive and developmental toxicity, and the pivots of further researches on environmental exposure, ecological effects and human health influences of PBDEs were thus suggested.

Sediment samples were collected from several sites in the upper, mid and lower reaches of the petroleum wastewater irrigation channel in eastern Shenyang of China, and the concentrations of their Cu, Zn, Pb, Cd and mineral oil were analyzed. The results showed that the pollutants were accumulated in all of sediment samples, with 408-118,300 mg x kg(-1) mineral oil, 17.83-78.53 mg x kg(-1) Cu, 35.76-155.16 mg x kg(-1) Zn, 8.50-31.03 mg x kg(-1) Pb and 0.1-1.0 mg x kg(-1) Cd. The sediments showed an inhibition or stimulation effect on plant root elongation and a lethal and sub-lethal effect on earthworm. The inhibition rate of root elongation based on germination test was -29.81 to 93.8%. During 14 d exposure, the maximum mortality rate of earworm was 100%, and during 14d and 28d exposure, the inhibition rate of its body weight growth was -36.6%-(-)6.08% and -40.4%-6.1%, respectively. The study indicated that a long-term irrigation with petroleum wastewater resulted in the accumulation of pollutants in channel sediments and enhanced eco-toxicity.

By using outdoor pot-culture method combined with biological magnetic effect analysis, this paper studied the effect of soil magnetization on soil-wheat ecosystem health. It was showed that there was an improvement in soil-wheat ecosystem health after soil magnetization, e.g., the germination of wheat seeds promoted, and the seedling height, individuals of leaves and roots, overall and active absorption area of roots and their absorption rates, and biological yield of mature wheat were increased. The ecological indicators of magnetic health effect were also discussed. 200 mT was the best parameter of magnetic treatment for wheat growth.

Sediment samples were collected from several sites in the upper, mid and lower reaches of the petroleum wastewater irrigation channel in western Shenyang of China, and the concentrations of their heavy metal Cd and mineral oil were determined. The results showed that pollutants were accumulated in all test sediments, with 400-12,500 mg x kg(-1) mineral oil and 1.6-27.2 mg x kg(-1) Cd. The sediments had significant inhibition effects on plant and earthworm. The inhibition rate of root elongation based on germination test was 10%-60%. During 14 d and 28 d exposure, the mortality rate of earthworm was 0%-70% and 0%-85%, and the inhibition rate of its body weight growth was -21.9%-17.7% and -18.6%-37.0%, respectively. It indicated that a long-term irrigation with wastewater resulted in the accumulation of pollutants in channel sediments and enhanced eco-toxicity. As an important source of pollution, the migration and release of pollutants in sediments possessed potential risks to underground water and soil.

To clarify the relationships between soil microorganisms and soil fertility under the condition of long-term fertilization, a 12-year fertilization experiment was installed on a fluvo-aquic soil, and the amount of soil microorganisms and the content of soil nutrients were determined and analyzed. The results showed that chemical fertilizers combined with organic manure could significantly improve soil fertility and increase the amount of soil microorganisms. Organic manure was obviously superior to corn straw in improving soil fertility. The correlation between soil microorganisms and soil fertility was significant. A positive correlation was found between the amount of bacteria and azotobacteria and the contents of organic matter, total N, alkalified N, total P and available P. The relationship between the amount of fungi and actinomycetes and the content of soil nutrients was not obvious.

In order to promote the further healthy development and disciplinary construction of the rising discipline pollution ecology of soil-plant systems and give full play to its more and more important role in solving environmental pollution and food-chain safety at the national level, this paper reviewed the inceptive work and early researches in this scientific area, traced the development of disciplinary definition and connotation, and basic principles and methods, and expounded and prospected the scientific mission, principal research contents and future development of this subject.

With the cognitive penetration of ecotoxicological effects into a molecular level, more attention has been paid to the research on DNA adducts. This paper analyzed toxic mechanisms and formative processes of DNA adducts, and introduced in brief their diagnostic methods, including chromatogram-mass spectrum method, 32P post-labeling method, immunology method and fluorescence method. The pollution-exposure indication of DNA adducts was expounded as an effective molecular biomarker, and thus, DNA adducts could be used by ecotoxicologists as a good caution signal in forecasting hazardous effects of pollutants.

Due to the abundant species and huge biomass, soil protozoa play an important role in soil ecosystem. As a bio-indicator, soil protozoa have many advantages over other soil animals. Studies on the community structures, quantities, and dynamic variations of biodiversity of soil protozoa could provide powerful means to evaluate natural environmental changes and to monitor the environmental pollution brought by anthropic activities. Based on the current study at home and abroad, this paper gave a review on the function of soil protozoa in ecosystems, their advantages as bio-indicator, and their responses to environmental factors, soil contaminants and the change of atmospheric CO2. The application prospect of soil protozoa in eco-toxicity diagnosis was also discussed.

As a part of mesofauna in soil ecosystem, nematode plays an important role in essential soil processes. Because of its unique attributes, nematode was widely used in the study of soil health indication. Based on the current studies at home and abroad, this paper discussed the function and application of nematode in indicating and diagnosing soil pollution, and the indices (maturity index, diversity index, similarity index, key species, N/C ratio, and physiological index) and their characteristics of nematode communities used as indicators. As a useful index of bioindicators in ecotoxicological diagnosis, the prospect of soil nematode application was of potential.

This paper examined the efficiency of a combined flocculants synthesized by aluminum and starch (noted as CAS) in treating kaolin suspension, domestic wastewater, municipal effluent and pulp-making wastewater. Jar test results showed that the flocculent performance of CAS was prior to polyaluminum-chloride (PAC) in treating different concentration kaolin suspension samples (100, 400 and 2000 mg x L(-1)). The optimal dose of CAS to each sample was 3.0, 2.0 and 2.0 mg x L(-1), being 60%, 50% and 50% of PAC, respectively. CAS also showed a priority to PAC in removing the COD and turbidity of domestic and municipal effluents. When treating pulp-making wastewater, the optimal dose of CAS was 70% of PAC. The removal rate of COD was enhanced 10%, the sludge was reduced 40%, and the sediment time was greatly shortened. It was also identified that the optimal concentration required to affect flocculation depended on the concentration and the character of the wastewater within the range examined. CAS was more effective in treating high turbidity wastewater.

Constructed wetland system for wastewater treatment is an important technological mode of economical and high-effective ecological treatment of wastewater, but it is still necessary to develop and perfect in its performance, and in particular, to make a continuous improvement and systematic optimization in its technical parameters. In this paper, the designing cruxes of constructed wetland systems for wastewater treatment at home and abroad were summarily discussed, and the optimal models and most adaptable values for constructed wetland systems were given on the basis of technological parameters such as hydraulic residence time, hydraulic conduction factors, surface loading rate, and engineering-construct design. In the meantime, some ecological methods were recommended to solve the management of wild animals and mosquito problems resulted from the operation of constructed wetland systems for wastewater treatment.

Three strains of Bacillus sp. BAll, BA19 and BA27, which can grow when phenanthrene is taken as the sole source of carbon and energy, were isolated from an oil-contaminated soil. Their crude extract was used to test the activities of polyphenol oxidase and catalase. The results demonstrated that all the three strains did not show a significant change in the activity of both enzymes when phenanthrene was lower than 200 mg x L(-1). Under different phenanthrene concentration, the enzyme activities of strains BA19, BA27 showed a higher stabilization than BA11. Using the SDS-PAGE contrasted the difference of proteins between the strains in normal medium and the strains growing on phenanthrene, the results showed that BA27 growing on phenanthrene synthesized a new protein with 27000 dal of molecular weight. At the same time, the synthesis of some proteins was cancelled. We conjecture that the new protein induced by phenanthrene may be related to the ability of phenanthrene degradation and the stabilization of enzyme activity by the strain.

Remediation technology for contaminated soils is being developed rapidly in recent years. However, there is a hysteresis in enacting remediation standards for contaminated soils. In particular, no corresponding research has been done in China. Methodology of enacting standards for the remediation of contaminated soils is discussed in order to promote the work in this field. It is emphasized that technological cleanup levels including limits of detection, environmental background levels and regulatory cleanup levels should be fully considered in the enactment of remediation standards.

Root-soil interface is the main entrance of pollutants intruding into plant tissues and the special micro-ecosphere that can result in a series of ecological safety problems. In this review, the concept of root-soil interface is presented and it is suggested that root-soil interface behavior and effects of chemical pollutants should be grouped into two aspects as rhizosphere chemical behavior and ecological effects and root chemical behavior and ecological effects. These two aspects are theoretically discussed according to the latest research advances. Rhizosphere chemical behavior and ecological effects included rhizosphere pH environment and adsorptive behavior, rhizosphere oxidation-reduction behavior, rhizosphere chemical toxicology effects, rhizosphere microbiological effects, and rhizosphere bioenzymatic reaction etc., and root chemical behavior and ecological effects included root exudation, influence of enzymatic systems in roots, disturbance of normal physiological processes, change of cellular structure and function, and interference of structure and function of biological macromolecules. Particular attention should be paid to the significance as well as some problems of research on chemical behavior and ecological effects of pollutants acting root-soil interface in pollution ecology.

The SARS virus origin which obviously differs from the theory of out-space origin and the theory of wildlife origin was theoretically discussed based on principles of pollution-evolution ecology, pathogenesis and infectant characteristics of SARS, and some relevant experimental evidence. It emphasizes on the fact that increasingly combined pollution in China provides a substantial basis for virus evolution. Gene recombination and fusion of more than one virus in ecosystems should take charge with the origin of a SARS virus. In particular, a common cold or influenza virus can acceleratedly changed into a superpower common cold or influenza virus through genetic mutation and gene recombination by increasingly combined pollution. This work can be useful for human beings to overcome SARS in theory.

The research on combined pollution in soil-plant systems is a scientific frontier of pollution ecology, and has an important significance in ecological safety of agricultural environment. The origin of combined pollution as a conception and its connotation development were reviewed. Types of combined pollution occurred in soil-plant systems and relevant progresses in this area were summarized. Ecological effects resulted from combined pollution of soil-plant systems and their quantificational tokens were expounded. The interactions of heavy metal-organic pollutant and organic pollutant-pathogenic microorganisms were pointed out to be important combined pollution in soil-plant systems, and the studies on the interactions, sub-products and their aged process, and moletoxicology mechanism of multi-pollutants were suggested to be the future keystone contents in this area. Meanwhile, the prospective studies on the methods and application of the results of combined pollution were put forward to provide a support for the warning and remediation of soil pollution.

Combined flocculants with higher environmental safety and lower ecological risk are urgently required in the process of water and wastewater treatment. HECES, a kind of flocculants with high effect and high ecological safety was synthesized by natural and biodegradable polysaccharide starch of corn and inorganic aluminium salt. Flocculent performance includes sediment character and turbidity removal rate. The jar test results showed that the flocculent performance of HECES with the dose of 3.0 mg.L-1 was prior to the combined adding 4.5 mg.L-1 PAC and 1.0 mg.L-1 PAM in treating kaolin suspensions. The optimal concentration of HECES was 8.0 mg.L-1 and 4.0 mg.L-1 in treating domestic wastewater and municipal effluent respectively, with the comparison to 50% an 40% of PAC, the removal rate of turbidity reached 95% and 99%, respectively. It was also identified that the optimal concentration required to effect flocculation depended on kaolin concentration, and on the character of the wastewater within the range examined. It could be more effective to treat wastewater with higher concentration of HECES. The flocculating performance would be better at pH 4.0-9.5. The superior ecological safety of HECES was due to its lower dosage and its lower concentration of residual activated aluminium.

Nitrate reductase, peroxidase, water-soluble sugars, root vitality and total biomass of Brassica napus seedlings were investigated with soil after magnetization treatment. The results showed that nitrate reductase activity was increased by 10.76% after 200 mT treatment. The contents of water-soluble sugars were increased by 11.05% and root vitality by 26.40% for 300 and 100 mT treatments, respectively. Total biomass also showed a trend of increase as the magnetization increased. The highest biomass of the above-ground parts was achieved at 300 mT, which was 13.28% higher than that of control. In addition, total biomass of below-ground parts was the highest at 200 mT, which was 13.17% higher than that of control, and the ratio of below-ground to above-ground parts decreased by 10.00%, suggesting that the overall environmental quality of the soil was improved significantly.

Studies on the thermodynamics and kinetics of copper (Cu2+) adsorption by phaeozem and burozem showed that that the adsorption of Cu2+ by these two soils was increased with the increasing concentration of Cu2+ within the range of Cu2+ concentrations used in the experiment, but the amount of Cu2+ adsorbed and fixed on phaeozem was much higher than that on burozem. When the test Cu2+ concentration in adsorption equilibrium was 95 mg.kg-1, its adsorption by burozem was nearly 3720 mg.kg-1, whereas by phaeozem was as high as 6076 mg.kg-1. Under the highest CuCl2 treatment of 400 mg.kg-1, Cu2+ adsorbed by phaeozem and burozem was 6159.0 mg.kg-1 and 4736.6 mg.kg-1, respectively. The adsorption of Cu2+ by the test soils could significantly conform to the Freundlich and Temkin equation, while Langmuir equation was not applicable to describe the isothermal adsorption processes of Cu2+ by the two soils. The adsorption of Cu2+ by the test soils was very rapid, which could reach its balance after 15-20 min. The adsorption within the first 2 min at its beginning stage accounted for 90% of the Cu equilibrium adsorption. The adsorptive rate of Cu2+ by phaeozem was decreased more quickly than that by burozem with the time. The two-constant equation was the optimal model to describe the adsorption of Cu2+. The other models in point were first-order dynamic equations and Elovich equations, whereas parabolic diffusion equations were not suitable ones.

Growth of soybean (Glycine max) seedlings, changes of superoxide dismutase (SOD) activities, and malonyldialdehyde (MDA) contents were researched during different concentration phenanthrene stress and following recovery from stress. The results showed that seedling growth was interrupted after 5 d in 200 micrograms.g-1 phenanthrene treatment. However, during the period of recovery, growth was restored, although there was a delay in returning to control levels. The dose-related response of SOD activities were observed in manner of linear for 2 d and of parabola for 5 d and 8 d at 50-200 micrograms.g-1 phenanthrene. SOD activities of seedling were significantly induced by 100 and 200 micrograms.g-1 phenanthrene for 2 d (P0.05 and P0.01), while declined significantly under phenanthrene stress for 8 d, and was 88% of control at 200 micrograms.g-1 phenanthrene (P0.05). When releasing soybean seedlings from phenanthrene stress for 5 d to clear tap water for 2 d or 4 d, their SOD activities at 50 and 100 micrograms.g-1 phenanthrene recovered towards control level, while a significant increase in SOD activities was observed at 200 micrograms.g-1 phenanthrene (P0.05). The experiments also revealed that a significant increase of MDA contents in seedlings occurred after 5 d and 8 d in 100 and 200 micrograms.g-1 phenanthrene treatment (P0.05 and P0.01), which suggested that the membrane systems were damaged by phenanthrene stress. All of the above results showed that SOD activities of soybean seedling might be suitable to be the biomarkers of phenanthrene stress.

Effects of 1, 2, 4-trichlorobenzene (TCB) stress on seedling growth, cell division and chromosomal aberration frequency of root-tip cells of Vicia faba were studied. The results indicated that the growth of the root length and mitotic index of root tip cells were successively decreased and even stopped with the increase of TCB concentrations and treatment duration. Numerical and structural chromosomal aberrations at metaphase and anaphase of root-tip cells in Vicia faba seedlings were produced by 50-300 micrograms.g-1 TCB treatment for 12-96 h. The percentage of c-mitosis, chromosomal bridge and chromosomal asymmetry array in root tip cells exposed to 50-100 micrograms.g-1 TCB for 12-24 h was up to 1.0-10.3%. The percentage of chromosomal stickness (S), chromosomal stickiness + chromosomal breakage (S + B), chromosomal stickness + chromosomal ring (S + R), chromosomal stickiness + chromosomal asymmetry array (S + A) and chromosomal stickness + chromosomal bridge (S + Be) in root tip cells reached 47.9-88.9%, and 18.1-29.6% for different kinds of chromosomal breakage at 300 micrograms.g-1 TCB for 12-96 h. Thus, the chromosomal aberration of root tip cells in Vicia faba seedlings could be used as a sensitive biomarker of monitoring soil contaminated with TCB.

Investigations on the effects of different application dosage of Machete and Londax mixture to control weeds in paddy fields showed that applied common and double dosage could effectively control weeds, and the controlling effects exceeded 80% and 90%, respectively, while there were some inhibiting effects to height and branch number of rice, and some resistance of weed had appeared. Weed contest might make rice get some compensation in height and branch under the condition that no herbicide and half dosage were applied, but the rice yield was decreased 36.01% and 54.80%, respectively, mainly because of the decrease of the number of effective panicles and grain number per panicle. The narrow economic benefit of the herbicides should be high.

A population of earthworm Eisenia foetida was exposed to single and binary-combined contamination of phaeozem by methamidophos, acetochlor and Cu. The result showed that one of three test chemicals had its toxicity on the earthworm population, and the single toxic sequence of the chemicals was acetochlormethamidophosCu. The values of their LD50 were 0.307, 0.708 and 118.70 mg.kg-1, respectively. The difference was depended on the biological mechanisms of the earthworm population. Acetochlor and Cu in soil could be absorbed by the earthworm population through penetrating through the skin of an earthworm. The result also showed that Cu could swell the toxicity of methamidophos, whether it was in low or high concentration by the binary-combined toxic effect test. Cu in low concentration could decrease the toxicity of acetochlor, but in high concentration, Cu could increase the acetochlor toxicity in soil. Therefore, these three pollutants were dangerous to the ecological security of soil ecosystem and soil-health quality. Furthermore, when the chemicals in same soil environment act one another, they could boost up the potential danger of soil ecosystem contaminated by the three pollutants. The joint toxic effects of various chemicals were in relation to their different concentration combinations in soil.

The combined effects of Cu, Cd, Pb and Zn on the growth and activity of the seminal roots of wheat (Triticum aestivum) were studied by the method of quadratic regression revolution design. The mathematical models describing the above relations were established. As for the toxicity to the root vitality, their single effects, marginal utility and combined effects between two heavy metals were analyzed. The results showed that Pb had the most important effect on the activity of root, and then, Cu, Cd and Zn in sequence. The interaction between Cu and Cd, Cu and Zn, Zn and Cd, Cd and Pb had great effects on the activity of seminal roots. Furthermore, among the concentration range of 0 to 20 mg.L-1, as for Cu and Zn, the lowest density had the biggest marginal utility, while Cd and Pb had the biggest ones at the highest density.

Molecular microbial ecology is an interdisciplinary field of molecular biological techniques and microbial ecology, which deals with microbial population, diversity, function, and relationships between microorganisms and biotic and abotic environments in microbial ecosystem. All the progress in molecular microbial ecology, especially in microbial diversity, phylogeny and communities of some microoganisms, indicate the renovation in traditional microbial ecology by the introduction of molecular techniques and strategies. This article reviewed the ideation, development, key domains, main methods and the future hot fields in molecular microbial ecology.

Rhizosphere is a special 'ecological remediation unit' to treat contaminated soils, which contains a great quantity of microorganisms such as fungi and rhizobacteria living with plant roots. Thus, physiological and ecological roles of plant roots to remedy contaminated soils, to accumulate and to solidify heavy metals, to absorb and degrade organic pollutants in rhizosphere were illustrated, and the function of mycorrhizospheric fungi to absorb, barrier and chelate heavy metals, to degrade organic pollutants through their metabolism activities, the action of rhizobacteria to absorb and solidify heavy metals, to degrade organic pollutants in rhizosphere through their active living activities, and the combined remediation of fungi and bacteria to pollutants in rhizosphere and their relevant mechanisms were explained. It was suggested that the remediation role of rhizosphere was the main part of phytoremediation, and one of the main basic theories to remedy contaminated soils by the activity of green plants and other organisms. The use of hyperaccumulative plants in remedying soils contaminated by some heavy metals would be prospective. It would be one of the important approach to contaminated soils remediation by organic pollutants through the mechanism of screening some special plants whose roots had strong secreting ability to absorb and accumulate dissolvent organic pollutants on the basis of inoculating specific or non-specific fungi and bacteria from the rhizosphere. This will be a developing trend of research on the remediation of contaminated soils by organic pollutants.

Pot culture experiment on the effects of 1,2,4-trichlorobenzene (TCB) stress on active oxygen metabolism of germinated soybean seeds indicated that during the beginning (1st-3rd day) of 100-300 micrograms.g-1 TCB treatment, the respiratory peak appeared earlier, and the respiratory rate, the accumulation of superoxide radical (O2-.) and H2O2, as well as the malondialdehyde (MDA) content were all enhanced. During 1-6 days of TCB stress, peroxidase (POD) activity gradually increased, and superoxide dismutase (SOD) activity increased firstly, and decreased afterward. These results suggested that the injury effects of TCB stress on germinated soybean seeds were achieved by excessive accumulation of active oxygen resulted from the degradation of active oxygen scavenging enzyme system.

Internationally applied ecology was born around 25-40 years ago in order to adapt and serve the needs of mitigating increasingly environmental pollution and ecological destroy in developed western countries at that time. All the times applied ecological principles thus underpin most efforts at solving increasingly deterioration of natural resources and serious eco-environmental problems as its keystone and researching kernel with the development of the subject. At the advent of the 21st century, human beings enter into the age of applied ecology. There are five international features of applied ecology, including more attention to many-sided applications, special emphasis on the intersection with engineering, strongly keeping on mutual links with basic ecology, omnidirectional adoption of new methods and new technology, and side-by-side trends of microcosmic mechanisms and macroscopical regulation. Although we must connect with international applied ecology and absorb distillates from the subject in developed western countries, development of applied ecology in China in the future, in particular, at the beginnings of the 21st century should not deviate from aiming at the solution of increasingly environmental pollution and ecological destroy that is one of the most important basic situations of the country.

The eco-toxicity of Cu, Zn, Pb, and Cd in the single form was tested with four types of soils(red loam soils, meadow brown soils, chestnut soils, and dark brown soils) and their combined effect was determined with meadow brown soils. The results showed that with the same content of heavy metals, the root elongation was strongly inhabited than the seed germination, and it indicated that root was more sensitive to heavy metals pollution. The inhibition rate of heavy metals pollution on the root elongation (IRHMRE) of wheat was significantly related with the contents of organic matter (OR) and Kjedahl-nitrogen (K-N) in soils (R2OR = 0.91, R2K-N = 0.92). However, IRHMRE was not significantly related with soil pH as did with OR and K-N, so does the content of CEC (R2pH = 0.62, R2CEC = 0.60). Whether under the low concentration of Cu, Zn, Pb, and Cd resulted in an irritated effect in root elongation, or under high concentration resulted in an inhibition effect in the single form, an synergistic effect occurred in the combined form.

Effects of various doses of 1,2,4-trichlorobenze on seed germination and seedling growth of soybean were studied. The results indicated that 50-200 micrograms.g-1 of 1,2,4-trichlorobenze had no effect on the percentage of seed germination, but delayed the rate of seedling growth. The seed germination was stopped by 300 micrograms.g-1 of 1,2,4-trichlorobenze. The most activity of SOD took place on the 4th day after sowing of soybean seed in the normal condition, then tended to be in a certain level with a little alteration. Under the various dose stress of 1,2,4-trichlorobenze, the activity of SOD in soybean hypocotyl was decreased, while MDA and protein contents as well as diameter of hypocotyls increased. Seedlings growth, fresh weight(FW), dry weight(DW) were inhibited, while the ratio of FW/DW didn't change. Damage-level of wheat seedlings was increased with increasing 1,2,4-trichlorobenze concentrations. Roots were more sensitive to 1,2,4-trichlorobenze-stress than hypocotyls.

Acute and sub-acute lethal effects of single and combined Cu, Zn, Pb and Cd on earthworm was determined using meadow brown soil. Results indicated that the mortality of earthworm was significantly related with the concentrations of Cu and Zn in the soil (alpha = 0.05, RCu = 0.86, RPb = 0.87), and the inhibition rate of earthworm growth was significantly related with the concentration of Cu in the soil (alpha = 0.05, RCu = 0.84). There was no significant relation between the concentrations of other heavy metals tested and the death rate and the growth-inhibition rate. The degree of individual earthworm enduring the toxicity of heavy metals varied greatly. The threshold concentration of toxicity defined by statistical method, the level to conduce the death of individual earthworm was 300 mg.kg-1 for Cu, 1300 mg.kg-1 for Zn, 1700 mg.kg-1 for Pb, 300 mg.kg-1 for Cd. LC50 was 400-450 mg.kg-1 for Cu, 1500-1900 mg.kg-1 for Zn, 2350-2400 mg.kg-1 for Pb and 900 mg.kg-1 for Cd. Combined effects of single Cu, Zn, Pb and Cd to conduce more than 10% of the death rate of earthworm could result in 100% of the death rate of earthworm, thus showing the strong synergistic joint effect of the heavy metals.

Ecotoxicological indexes of wheat, Chinese cabbage and rice exposed to reactive X-3B red dye were studied using the experimental method of crop seed exposure. The results showed that reactions of the three crops to reactive X-3B red dye were different from each other. Based on the inhibition of seed gemination, the half effect concentration(IC50) of wheat, Chinese cabbage and rice was 8965, 7010 and 7514 mg.L-1. Based on the inhibition of root elongation, the IC50 of wheat, Chinese cabbage and rice was 6534, 5882 and 4570 mg.L-1. When seedlings were cultured for seven days after the gemination of seeds and the remaining seeds or husks were discarded, fresh and dry growing biomass of the three crops exposed to the dye was both decreased with the increasing the concentration of reactive X-3B red dye. However, the decrease rate of fresh biomass was higher than that of dry biomass. Biomass index of wheat was most sensitive to reactive X-3B red dye, followed by rice, and Chinese cabbage was most inertia when the crops were exposed to reactive X-3B red dye with the high concentration of 4500 and 5000 mg.L-1. As far as the tolerance of wheat, Chinese cabbage and rice to reactive X-3B red dye was concerned, wheat had the strongest tolerance, on the contrary rice had the wakestone.

Nucleicacid probe detection, PCR technique using primer, DNA sequential analysis, and electrophoresis separation and display were summarized and the application of these techniques to research on environmental pollution and future developing directions were discussed. It was pointed out that molecular-ecological technology of microorganisms are playing an important role in studying on relationships between microorganisms and contaminated environment. There are some important advances such as genetic adaptation and evolutionary mechanisms of microorganisms in contaminated environment, the positioning of pollutant-degrading genes of microorganisms and the construction of microbiological engineering bacteria, thus promoting the development of molecular ecology for bioremediation of contaminated environment.

Reactive X-3B red dye entering into environment is a typical persistent organic pollutant(POPs). Transport of the dye from water to soil and from soil to crop compartment is a continuous ecological process. According to the cognitionm, the quantitative depiction of the process using mathematical models was theoretically discussed. Some of the mathematical models were also verified using burozem-soybean, cinnamon soil-wheat, krasnozem-radish, aquorizem-rice systems. In particular, transference of the dye from water compartment to soil compartment by way of adsorbent mechanisms was accorded with the Langmuir model, and movement of the dye from soil compartment to crop compartment on the basis of root-absorbing mechanisms could be expressed using logarithmic crop-soil accumulation factor(CSAF) models.

Since 1970s, pollution ecology has gone through several historical stages including the natal, growing and developing and expanding stage with the rise in environmental sciences and the development of applied ecology. The theoretical system and researching methods with special characteristic of the subject has taken shape. So far pollution ecology has become an independent discipline to probe into interactions between biological systems and polluted environment and to control and remedy polluted environment using ecological principles, is an important component part of applied ecology and derives from amalgamation and intersection between ecology is faced with challenges and opportunities. A breakthrough and good progresses will be made in its branches and frontal fields such as ecology of combined pollution, contaminant ecotoxicology, ecological processes of pollutants and ecological remediation of contaminated environment.

Effects of land utilization of sewage sludge on crops and soil environment were studied using sewage sludge from the Northern Shenyang Plant of Wastewater Treatment. The results showed that contents of nitrogen, phosphorus and organic matter in the soil were increased after the utilization of sewage sludge, thus being advantageous to growth and development of crops. The biomass of rice after having applied 22.5 and 45 t.hm-2 of sewage sludge was increased by 11.48%-11.83% compared with the control. There was no evident harmful effect of heavy methals from sewage sludge on quality of soil environment, agricultural products and underground water when the application of sewage sludge was controlled within the range of 45 t.hm-2.