Airborne bacteria are important biological components of bioaerosol and play an important role in ecosystem. Bacteria at a high concentration in the atmosphere can result in biological air pollution and all kinds of diseases. In this study, a systematical survey on the culturable airborne bacteria was carried out for 1 year at three sites in Beijing urban area. Results showed that concentrations of culturable bacteria ranged from 71 colony forming units (CFU)/m(3) to 22,100 CFU/m(3), and the mean was 2,217 CFU/m(3). Bacterial concentrations at the human activity-enriched site (RCEES) and the highly trafficked site (XZM) were virtually the same point. They were significantly higher than those at the greener site (BBG). Significant variation in bacterial concentrations in different seasons was observed at RCEES and XZM with higher concentrations in summer and autumn. In a single day, significantly lower concentrations were detected at 13:00 hours through all sampling sites. In this study, 165 species in 47 genera of culturable bacteria were identified. Micrococcus was one of the most dominant bacterial groups and contributed to approximately 20 approximately 30% of the total bacterial concentration, followed by Staphylococcus, Bacillus, Corynebacterium, and Pseudomonas. The bacterial species with a high concentration percentage included Micrococcus luteus and Micrococcus roseus.

Airborne fungi are being proposed as a cause of adverse health effects. They may adversely affect human health through allergy, infection, and toxicity. Moreover, they have a great influence on urban air quality in Beijing. In this study, a systematical survey on the culturable airborne fungi was carried out for 1 year in Beijing urban area. Fungal samples were collected for 3 min, three times each day, and continued for three consecutive days of each month with FA-1 sampler from three sampling sites. Results showed that the culturable fungal concentrations ranged from 24 CFU (Colony forming units) /m 3 to 13960 CFU/m 3 , and the mean and median was 1165 CFU/m 3 and 710 CFU/m 3 , respectively. Fungal concentrations in the greener area around the Research Center for Eco-Environmental Sciences (RCEES) and Beijing Botanical Garden (BBG) were significantly higher than in the densely urban and highly trafficked area of Xizhimen (XZM) (***Pb0.001), but no significant difference was found between RCEES and BBG ( PN0.05). The variation of fungal concentrations in different seasons was significant in RCEES and BBG, where the concentrations were higher in Summer and Autumn, and lower in Spring and Winter. However, there were no significant differences in fungal concentrations between the Spring and the Winter for three sampling sites ( PN0.05). Fourteen genera, including 40 species of culturable fungi, were identified in this study. Penicillium, with the most abundant species, which comprised more than 50% of the total isolated fungal species. Cladosporium were the most dominant fungal group, and contributed to more than one third of the total fungal concentration, followed by non-sporing isolates, Alternaria, Pencillium and Asperigillus. The concentration percentage of Cladosporium was significantly higher in RCEES than in XZM (*Pb0.05), and the concentration percentages of Penicillium (**Pb0.01) and Aspergillus (*Pb0.05) were higher in XZM than in RCEES and in BBG. For other groups' concentration percentages, no significant differences were observed among the sampling sites. The distribution pattern of airborne fungi presented log-normal distribution. The highest proportion of culturable fungi was detected in stage 4 (2.0-3.5 Am), and the lowest was in stage 6 (b1.0 Am). D

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To compare the human health risk of heavy metals and As in sewage sludge between adults and children, samples were collected from five wastewater treatment plants (WWTPs) located in the urban district of Taiyuan, the capital of Shanxi. Heavy metals and As in sewage sludge can be ranked according to the mean concentration in the following order: Cu > Cr > Zn > Pb > As > Hg > Cd. Compared with the concentration limit set by different countries, the heavy metals contents in sewage sludge were all within the standard limits, except for the content of As, which was higher than the threshold limit established by Canada. A health risk assessment recommended by the United States Environmental Protection Agency (USEPA) was used to compare the non-cancer risk and cancer risk between adults and children. Based on the mean and 95% upper confidence limit (UCL) of the average daily dose (ADD), heavy metals and As can be ranked in the order of Cu > Cr > Zn > Pb > As > Hg > Cd for adults, and Cu > Cr > Zn > Pb > Hg > As > Cd for children. Moreover, results of ADDingest and ADDinhale indicated that ingestion was the main pathway for heavy metals and As exposure for both adults and children, and the sum of ADD implied that the exposure to all heavy metals and As for children was 8.65 and 9.93 times higher, respectively, than that for adults according to the mean and 95% UCL. For the non-carcinogenic risk, according to the hazard quotient (HQ), the risk of Cu, Hg and Cr was higher than the risk of Zn and Pb. The hazard index (HI) for adults was 0.144 and 0.208 for the mean and 95% UCL, which was less than the limit value of 1; for children, the HI was 1.26 and 2.25, which is higher than the limit value of 1. This result indicated that children had non-carcinogenic risk, but adults did not. Furthermore, ingestion was the main pathway for non-carcinogenic risk exposure by the HQingest and HQinhale. For the carcinogenic risk, Cd and As were classified as carcinogenic pollutants. The values of RISK for the mean and 95% UCL for adults and children all exceeded the limit value of 1 × 10−5, which implied that adults and children had a carcinogenic risk, and this risk was higher for children than for adults. The results of RISK for As and Cd implied that As was the main pollutant for carcinogenic risk. Moreover, the results of RISKingest and RISKinhale indicated that ingestion was the main pathway. Uncertainty analysis was performed, and the risk ranges of it were greater than certainty analysis, which implied that uncertainty analysis was more conservative than certainty analysis. A comparison of the non-carcinogenic risk and carcinogenic risk for adults and children indicated that children were more sensitive and vulnerable than adults when exposed to the same pollutant in the environment.

This paper provides an overview of the trend of generation, composition, and management of municipal solid waste, and estimates the carbon emissions arising from municipal solid waste management in Beijing. The correlation analysis conducted shows that the generation of municipal solid waste in Beijing has been growing steadily, showing high correlations (r > 0.9) to the total GDP, per capita income, and the population. Food waste showed an increasing trend since 1990. Compared with the results of an investigation in 1990, ash and woodchips content in 2003 declined from 56% to 17%, while the percentage of paper and plastic increased from 10% to 29% over the same period. The calorific value of the municipal waste also increased, from 2,686 kJ/kg in 1990 to 4,667 kJ/kg in 2003, indicating that the waste is suitable for incineration. Currently, the source separation ratio of municipal waste is approximately 15%. About 94% of all the collected solid waste goes to the landfill while 4% is composted and 2% is incinerated. A moderate garbage collection fee is applied to both permanent and temporary residents in Beijing, but the willingness to pay for solid waste collection and treatment is still low. Under current treatment mode, the total amounts of carbon emission from waste disposal sites and incineration increased with the increase of municipal solid waste, from 29.8 Gg in 1990 to 84.5 Gg in 2003, including 83.3 Gg of CH 4 and 22.0 Gg of CO 2 . The data availability and methodological challenges in monitoring the quantity and characteristics of municipal solid waste are discussed.

During the investigation of endophytic fungi diversity in aquatic plants and the fungal diversity in soil in southwest China, we obtained 208 isolates belonging to Trichoderma, including 28 isolates as endophytes from aquatic plants and 180 isolates as saprobes from soil, respectively. Finally, 23 new species of Trichoderma are recognized by further studies. Their phylogenetic positions are determined by sequence analyses of the combined partial sequences of translation elongation factor 1-alpha (tef1) and gene encoding of the second largest nuclear RNA polymerase subunit (rpb2). The results revealed that the 23 new species are distributed in nine known clades. The morphology and culture characteristics are observed, described and illustrated in detail. Distinctions between the new species and their close relatives were compared and discussed. These include: Trichoderma achlamydosporum, T. amoenum, T. anaharzianum, T. anisohamatum, T. aquatica, T. asiaticum, T. asymmetricum, T. inaequilaterale, T. inconspicuum, T. insigne, T. obovatum, T. paraviride, T. pluripenicillatum, T. propepolypori, T. pseudoasiaticum, T. pseudoasperelloides, T. scorpioideum, T. simile, T. subazureum, T. subuliforme, T. supraverticillatum, T. tibetica, and T. uncinatum.

Heavy metals (HMs) in sewage sludge have become the crucial limiting factors for land use application. Samples were collected and analyzed from 32 waste water treatment plants (WWTPs) in the Shanxi Province, China. HM levels in sewage sludge were assessed. The multivariate statistical method principal component analysis (PCA) was applied to identify the sources of HMs in sewage sludge. HM pollution classes by geochemical accumulation index Igeo and correlation analyses between HMs were also conducted. HMs were arranged in the following decreasing order of mean concentration: Zn > Cu > Cr > Pb > As > Hg > Cd; the maximum concentrations of all HMs were within the limit of maximum content permitted by Chinese discharge standard. Igeo classes of HMs pollution in order from most polluted to least were: Cu and Hg pollution were the highest; Cd and Cr pollution were moderate; Zn, As and Pb pollution were the least. Sources of HM contamination in sewage sludge were identified as three components. The primary contaminant source accounting for 35.7% of the total variance was identified as smelting industry, coking plant and traffic sources; the second source accounting for 29.0% of the total variance was distinguished as household and water supply pollution; the smallest of the three sources accounting for 16.2% of the total variance was defined as special industries such as leather tanning, textile manufacturing and chemical processing industries. Source apportionment of HMs in sewage sludge can control HM contamination through suggesting improvements in government policies and industrial processes.