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Statistical characteristic analysis of pollutants in contaminated sites can help identify the origin, generation, and spatial variation of different pollutants, and can reduce the uncertainty of site survey data. Taking a large and abandoned contaminated coking site of China as the object, 114 surface (0-50 cm) soil samples were collected, with the statistical and spatial characteristics of 16 priority PAHs (sigmaPAHs) analyzed. The descriptive statistical analysis indicated that the sigmaPAH levels varied significantly, and the data were severely skewed. The correlation matrix (CM) and principal component analysis (PCA) showed that the extracted first two principal components (PCs) could effectively represent the whole site pollution data. Four pollutants, i. e., Baa, Bbf&Bkf, Bap, and Inp, were selected for trend analysis and spatial local variance analysis. In the east-west and north-south directions of the site, the pollution showed a low-high-low trend. The variation coefficient of pollution for the site was higher in the central, northwest, and southwest regions, while lower in the other regions.

Since the 1990s, most developed countries have issued the risk-based environmental standards or criteria for soil, as well as corresponding technical background documents, this provides methodological references for developing soil environmental standards and criteria in developing countries. However, because of the variability in legislation frameworks, derivation procedures of criteria, environmental conditions and climates, soil types, and habits and customs among countries, there are great differences in the names, roles and values of soil standards and criteria. This paper presents the scientific basis and fundamental features of soil environmental criteria. The definitions, functions and values of the soil environmental criteria in different countries were compared and analyzed. Key technologies for the development of soil environmental criteria and critical influence factors were summarized and analyzed, with special respect to the classification of land use types, setting of exposure scenarios and pathways, selection of acceptable risk levels for carcinogens, and the determination of exposure parameters. Strategies and countermeasures for the development of local or regional soil environmental criteria in China were proposed by referring to international experiences, and the current difficulties and challenges faced by China in the development of soil environmental criteria were discussed and addressed.

Abstract: 1,2-dichloroethane and tetrachlorethylene were studied in four different unsaturated porous media to determine the impact of the properties of media and fluids on the infiltration aided by digital image analysis technique. The results indicated that the whole process of NAPLs migration can be recorded dynamically using the digital image analysis technique. The unstable flow "fingering" occurred in the process of infiltration. Fingering mechanisms such as splitting, coalescing, and shielding were observed in the process of fingering. Front morphology of the infiltration was influenced by the properties of porous media and fluids. The vertical migration rates and the growth rates of area development were positively correlated to the size of medium particle and the density of the NAPLs (except for toluene) in the process of infiltrating. The number of fingers and the wavelength of fingering were also closely correlated with the properties of media and fluid. DNAPLs infiltrated faster compared with LNAPLs, which resulted in larger pollution area within the same infiltration time. It can be concluded that the environmental risk of DNAPLs is significantly greater than the LNAPLs.

A large coking contaminated site was selected to study the PAHs' spatial distribution probability in surface-soil (0-50 cm) through the indicator kriging of the non-parametric geostatistics, and the map of probability distribution with a contaminant target was plotted over the entire site. Results indicated that the indicator semivariograms were stable after the conversion of sample data, but the poor correlation of spatial samples was observed due to the spatial variability. In this site, the distribution of the contamination probability of four PAHs' showed a similar characteristic, and the areas with a probability of more than 45% were mainly distributed in production process workshops for coking, gas purification, tar products etc, of the central, northwest and southeast site with serious contamination, while the areas with a probability of less than 45% were mainly distributed in coal preparation, gas purification workshops of the southwest and northeast site. Based on the above analysis results, we can draw a conclusion that the forecast probability results are consistent with the occurrence and distribution of pollution sources, which is important for defining the remediation boundary and calculating the contaminated soil volume.

Frequently accidental spill of hazard materials into soil environment posed significant threats to human health and natural environment in China. In this paper, simulated nonaqueous phase liquid (NAPLs) toluene sudden spill in fluvo-aquic soil was performed in a two-dimensional tank to investigate the migration and distribution characteristics of toluene as well as its simulation through STOMP model. Visual observation showed that the horizontal expansion of toluene with concentration > 1 g x kg(-1) and > 20 g x kg(-1) were approximate 2.3 and 3 times the length of the corresponding vertical transportation, respectively. The result revealed that toluene exerted a preferential tendency to lateral spread compared to the vertical migration trends, which may contribute to the impeding effect as a result of the low permeable capacity of soil (permeability coefficient was 0.12 cm x h(-1)). The behavior and fate of toluene in heterogeneous soil layers (combined fluvo-aquic-sand and sand-fluvo-aquic soil layers, respectively) after spill were simulated using STOMP model and the results indicated that the significant difference in relative permeability of interface layer, due to the much higher value of permeability coefficient of sand (29.70 cm x h(-1)) than that of fluvo-aquic soil, played an important role on the redistribution of toluene after its spill into the heterogeneous soil layers. For practical purposes, the results of this study may be beneficial to identify the distribution property of NAPLs in time after its release into the soil environment.

A review of species of the genus Neopsocopsis Badonnel, 1936 is presented. Four species are redescribed, viz. Neopsocopsis hirticornis (Reuter, 1893), Neopsocopsis quinquedentata (Li & Yang, 1988), Neopsocopsis profunda (Li, 1995), and Neopsocopsis flavida (Li, 1989), as well as the description of one new species, Neopsocopsis convexasp. n. Seven new synonymies are proposed as follows: Pentablaste obconica Li syn. n. and Pentablaste clavata Li syn. n. of Neopsocopsis hirticornis, Pentablaste tetraedrica Li syn. n. of Neopsocopsis longiptera, Neoblaste schizopetala Li syn. n. and Neoblaste flavae Li syn. n. of Neopsocopsis profunda, Blastopsocidus pini Li syn. n. and Pentablaste lanceolata Li syn. n. of Neopsocopsis flavida. Neopsocopsis hirticornis (Reuter, 1893) is recorded from Japan and China for the first time, and Neopsocopsis longiptera Vishnyakova, 1986 is newly recorded from China. Illustrated keys to adult males and females are presented.

Soil profile samples of isohumosol, primosol, and ferrosol were obtained in relatively clean areas of China. Concentrations and chemical speciation of rare metals [e.g., Ag (Silver), Bi (Bismuth), In (Indium) and Sn (Tin)] were determined, in which sequential extraction was used to fraction metals. Vertical distributions of elemental enrichment ratios (ERs) were used to study the anthropogenic influence. The mobility of metals was characterized by the sum of exchangeable form and carbonate-bound form. Average concentrations of Ag, Bi, In and Sn in the A horizon were (0.14 +/- 0.01), (0.49 +/- 0.09), (0.050 +/- 0.01), and (2.8 +/- 0.9) mg x kg(-1), respectively. The ERs were close to 1. Average distributions of metal speciation were: Ag, residual (65.8%) > H202-extractable organically bound (H2O2-Org) (25.9%) > Amorphous metal oxide-bound (am-MeOx) (4.2%) > Metal-organic complex-bound (Me-Org) approximately Crystalline Fe oxide-bound (cr-FeOx) (2.0%); Bi, residual (29.2%) > H2O2-Org (27.1%) > cr-FeOx (22.7%) > am-MeOx (18.8%) > Me-Org (1.0%) > carbonate-bound (0.9%) > easily reducible metal oxide-bound (re-MeOx) (0.3%); In, residual (67.8%) > cr-FeOx (17.0%) > am-MeOx (6.8%) > H2O2-Org (6.0%) > carbonate-bound (1.4%) > Me-Org (1.0%); Sn, residual (58.1%) > am-MeOx (23.0%) > cr-FeOx (15.6%) > H2O2-Org (1.8%) > Me-Org (1.1%) > exchangeable approximately carbonate-bound (0.2%). the results indicated that the exogenous elements enrichment was deficiency to minimal, and the concentrations of the rare metals were close to background values of soil in studied areas. Rare metals were stable in soils. The mobility of metals was in the order In > Bi > Sn > Ag.

Cold-adapted microorganisms such as psychrotrophs and psychrophiles widely exist in the soils of sub-Arctic, Arctic, Antarctic, alpine, and high mountains, being the important microbial resources for the biodegradation of petroleum hydrocarbons at low temperature. Using the unique advantage of cold-adapted microorganisms to the bioremediation of petroleum hydrocarbon-contaminated soils in low temperature region has become a research hotspot. This paper summarized the category and cold-adaptation mechanisms of the microorganisms able to degrade petroleum hydrocarbon at low temperature, biodegradation characteristics and mechanisms of different petroleum fractions under the action of cold-adapted microorganisms, bio-stimulation techniques for improving biodegradation efficiency, e. g., inoculating petroleum-degrading microorganisms and adding nutrients or bio-surfactants, and the present status of applying molecular biotechnology in this research field, aimed to provide references to the development of bioremediation techniques for petroleum hydrocarbon-contaminated soils.

The batch equilibration experiments were carried out to study the adsorption characteristics of Ag+ and the effect of pH on the adsorption process in two typical Chinese soils, which the phaeozem from Northeast China and the red soil from Hunan province. The species transformation of Ag+ was investigated in the experiments using the sequential extraction method. The results showed that an adsorption quantity of Ag+ for both soils increased with increasing solutions initial pH. Adsorption quantity of Ag+ in the two soils also increased with increasing of initial Ag+ concentration in the range from 0 to 100 mg x L(-1), specifically, going up quickly in the concentration range of 0-20 mg x L(-1), but increased gently when Ag+ concentration exceeded 20 mg x L(-1). The Ag+ adsorption data of both soils were adequately described by Langmuir isotherm occurred in Ag+ sorption processes, their maximum adsorption quantities were 250 mg x kg(-1) the phaeozem soil and 88.5 mg x kg(-1) in the red soil, indicating a much higher adsorption capacity in northeast phaeozem soil than that of Hunan red soil. The two soils had similar adsorption kinetic characteristics, with respect to quickly reaching equilibrium within 30 minutes, but the adsorption rate of phaeozem soil was significantly greater than that of the red soil. The species analysis of Ag showed that exchangeable Ag and residual Ag increased in red soil, and metal-organic complex-bound Ag, exchangeable Ag, carbonate-bound Ag and residual Ag increased in phaeozem, respectively.

Environmental health risk of contaminated soil in a typical abandoned industry was analyzed based on the full field investigation according to the site assessment procedure of American Society for Testing and Material (ASTM). Parameters were modified with the combination of Chinese crowd character and site specifics. Results indicated that the site was mainly contaminated with volatile and semi-volatile organic compounds in soil profiles. And the contents of carbon tetrachloride, tetrachloroethylene, pentachloroethane, hexachlorobutadiene, hexachloroethane and hexachlorobenzene in soil samples were exceeded the national environmental standard. These contaminants ranked the carcinogenic risks and hazard quotients more than 10(-2) and 1 in some locations with the exposure by oral ingestion, dermal contact and inhalation. Contaminants in this site had resulted in the high health risks to the residents and surrounding communities. The risk should be reduced to the health acceptable level by the treatment and remediation before further development for residential and commercial utilization.

A new phenolic glycoside and three known compounds were isolated from the seeds of Cucurbita moschata. The structures of the new compound was elucidated as phenylcarbinyl 5-O-(4-hydroxy)benzoyl-beta-D-apiofuranosyl (1-->2)-beta-D-glucopyranoside on the basis of spectroscopic analysis and chemical evidence. Three known compounds were identified as 1-O-benzyl[5-O-benzoyl-beta-D-apiofuranosyl(1-->2)]-beta-D-glucopyranoside 2, cucurbitosides C 3 and A 4, by comparison of the spectral data with reported data. Compound 2 was isolated from this plant for the first time.

Levels and distribution of organochlorine pesticides (OCPs) were investigated in soils along Haihe River and in Haihe Estuary area. 31 surface soil samples were collected on August 2007, and they were extracted using accelerated solvent extraction. The HCHs and DDTs contents in soils were determined by gas chromatography with an electron capture detector (GC-ECD). The results show that the concentrations in soils range from n.d. to 1,728 microg x kg(-1) with a mean value of 93.9 microg x kg(-1) for HCH congeners, and from n.d. to 288 microg x kg(-1) with a mean value of 34.4 microg x kg(-1) for the sum of p,p'-DDT, o,p'-DDT, DDE, and DDD, respectively. The HCHs is dominant, accounting for 72 percent of total OCPs content. The working hypothesis is that OCPs levels and distribution in the area are dependent on the degree of anthropogenic intervention. Higher concentrations of total OCPs are found in the chemical industrial region, and ones from Haihe River area are higher than Haihe Estuary area, due to impact from chemical industrial emissions. According to the isomers of HCHs and metabolites of DDTs, HCHs and DDTs in soils in this area may be derived from the use of pesticide in agricultural and industrial emissions in history, though having recent inputs of OCPs at a few sites. Compared with those in other national or international regions, the concentrations of HCHs and DDTs in soils from Haihe River area are higher. It can be concluded that soil OCPs levels are relatively high in this area.

Four different soil particle-size fractions that is clay, silt, fine sand and coarse sand ( <2 microm, 2-20 microm, 20-200 microm, > 200 microm) from the topsoils in an organochlorine pesticide (OCP) field were separated by physical method to characterize the OCPs distribution in soils and to study the effect of organic matter and mineral composition in different separates on pollutants distribution. The results show that the concentrations of HCHs and DDTs in silt with 463.1 mg x kg(-1) and 1225.6 mg x kg(-1) are higher than those in coarse sand, 157.8 mg x kg(-1) and 384.5 mg x kg(-1), respectively. There is a significant correlationship between IgKoc. and the contents of HCHs and DDTs in clay. The analysis on X-ray diffraction of organo-mineral aggregates demonstrates that clay and silt have a much higher content of the clay minerals than those in coarse sand within the contaminated soils. There are some differences with different particle-size fractions in the content and composition of the clay minerals in organo-mineral aggregates, which affect the OCP distribution in soils to some extents. The results also suggest that the distribution of HCHs and DDTs in the particle with more pollutants in the site is similar to that in airborne particles. So the environmental behavior of OCPs in topsoils from the contaminated site should be paid more attention especially in ambient air-soil interaction.

Objective: To analyze the monosaccharide composition in the polysaccharides from Rhaponticum uniforum, determine the content of monosaccharide, and provide some references for further research., Method: The monosaccharide composition was determined by high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). Phenol-sulfuric acid method was used for the determination of the content of polysaccharide., Result: The monosaccharides composition in polysaccharides from R. uniforum are glucose, arabonose and fructose. Their molar ratios are 1 : 1.61 : 2.21. The content of polysaccharide is 95.78%, taking the mixture of monosaccharide compositions as reference substances., Conclusion: HPAEC-PAD can be used to analyze the monosaccharide composition in the polysaccharide with high precision, and the method of phenol-sulfuric acid is simple, convenient and reliable.

bstract:A laboratory leaching experiment on simulated acid rain was carried out using soil columns. The release of Si, Al and Fe from soils and pH values of eluates were investigated. The results showed that under the given leaching volume, the release amounts of cations were influenced by the pH value of simulated acid rain, while their response to acid rain was different. Acid rain led to Si release, nearly none of Fe. Within the range from pH 3.0 to 5.6, a little Al release but mass Al only release at the pH below 3.0, both Si and Al had a declining release ability with the undergoing eluviation. At pH 2.5, the release amounts of Si and Al, especially Al, increased significantly with the strengthened weathering process of soil mineral. With an increase of the leaching amount of acid rain, the release of Si and Al increased, but acceleration of Si was slower than Al which was slower and slower. When the soil pH falling down to a certain grade, there are negative correlation between pH and both Al and DOC concentration of eluate. released, but most of Al derived from the aluminosilicates dissolved. Acid deposition can result in solid-phase alumino-organics broken and Al released, but most of Al derived from the aluminosilicates dissolved.

Polychlorinated biphenyls (PCBs), hexachlorocyclohexanes (HCHs) and dichlorodiphenyl-trichloroethanes (DDTs) were analyzed in the surface water of Haihe River and Bohai Bay, in north of China. Concentrations of PCBs, HCHs and DDTs were 0.31 - 3.11 microg/L, 0.30 -1.07 microg/L and 0.02 - 0.15 microg/L in river, and in sea were 0.06 - 0.70 microg/L, 0.05 - 0.75 microg/L and 0.01 - 0.11 microg/L respectively. Mostly, the PCBs, HCHs and DDTs in the Bohai Bay are from terrestrial input by Haihe River. PCBs and organic chlorinated pesticides (OCPs) are positively correlated with DOC (dissolved organic carbon). The levels of PCBs and OCPs in Haihe River in this study are quite higher than the similar surface waters in China, while the levels in Bohai Bay are quite consistent with similar waters abroad.

Objective: To study the effects of Rhaponticum uniforum polysaccharide on immune function in normal mice and the underlying mechanism., Method: SRBC and ovalbumin were employed as antigens to be injected to mice, respectively. Three doses of R. uniforum polysaccharide (50, 100, 200 mg x kg(-1) x d(-1)) were given orally for seven days. After the secondary immunization, the level of corresponding antibody and the concentration of serum IL-2, IFN-gamma were determined., Result: The levels of antibodies (anti-SRBC and anti-ovalbumin) and cytokines (IL-2 and IFN-gamma) in median dose group of R. uniforum polysaccharide were all significantly higher than those in control groups (P <0.05)., Conclusion: R. uniforum polysaccharide could enhance the immune function in normal mice.

The synergetic effect of dissolved oxygen (DO) in the photodegradation of propisochlor aqueous solution was investigated in the presence of UV. With the increase of dissolved oxygen concentration, from 0 to 7.5 mg/L, photodegradation of propisochlor was accelerated. After the concentration of 7.5 mg/L, the rate and efficiency of photodegradation stopped increasing and began to decrease when the concentration became higher. During the photolysis process, dissolved oxygen was consumed. It suggested that the oxygen took an active part in the photolysis. It was found by analysis that the pohtolysis products under different dissolved oxygen concentrations were almost the same, but the production of several products was different. Singlet oxygen (1O2) as the resonance intermediate in the photolysis systems was confirmed by electron spin resonance spin trapping experiments.