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Components of chromophoric dissolved organic matter (CDOM) from eight coastal land-based shrimp ponds in the Minjiang, Mulan, and Jiulong rivers of subtropical southeastern China were determined by fluorescence excitation emission matrix spectroscopy combined with parallel factor analysis (EEMs-PARAFAC). Four separate fluorescence components, including two protein-like components (C1, C4) and two humic-like components (C2, C3), were identified as the dominant components of the CDOM in these shrimp ponds. The fluorescence indices (FI, BIX, and HIX) suggest that the CDOM of shrimp ponds shows low humification and is mainly derived from spontaneous sources. The protein-like and humic-like components have similar sources and exhibit a similar geochemical behavior. The salinity is negatively correlated with all CDOM fractions, whereas the DOC concentrations show only a positive correlation with the humic fractions of the CDOM. This study provides a scientific basis for the photochemical properties of CDOM in shrimp ponds.

In order to identify methane (CH 4 ) diffusion emissions characteristics and their impact factors in an eutrophic lake, CH 4 flux across the lake-air interface was observed in Meiliang Bay and the central zone of Lake Taihu over one year. The relationships between CH 4 flux and environmental factors and water quality indices were analyzed. The results indicated that the annual mean CH 4 diffusion flux in the eutrophic zone was significantly higher than that in the central zone, which were 0.140 mmol·(m 2 ·d) -1 and 0.024 mmol·(m 2 ·d) -1 , respectively. Additionally, the highest CH 4 flux appeared in the eutrophic littoral zone. The CH 4 flux varied seasonally, which was consistent with water temperature that peaked in summer. Furthermore, the difference in CH 4 flux between seasons was an order of magnitude. The temporal variation in CH 4 flux was mostly driven by wind speed and water temperature. The spatial correlation between CH 4 flux and dissolved organic carbon concentration was highly significant ( R 2 =0.62, P <0.01). Observing temporal and spatial patterns of CH 4 flux was necessary to accurately estimate whole-lake CH 4 emissions due to large variability across time and space.

In order to evaluate the effects of nitrogen deposition on CO 2 and CH 4 fluxes from a Cyperus malaccensis marsh in the Min River estuary at Daoqingzhou, Fujian, static chamber-gas chromatography (GC) techniques were used. CO 2 and CH 4 fluxes at a control (CK)[0 g·(m 2 ·a) -1 ], N1[24 g·(m 2 ·a) -1 ], N2[48 g·(m 2 ·a) -1 ], and N3[96 g·(m 2 ·a) -1 ] were measured and analyzed and the related environmental factors were recorded. The results show that,① compared to the control treatment, the effects of nitrogen deposition on the CO 2 fluxes for N1 and N3 increased by 20.30% and 4.06%, respectively, whereas the CO 2 fluxes for N2 reduced by 10.05%, furthermore, the CO 2 fluxes under different treatments were not significantly different ( P >0.05), except for the N2 and N3 treatments in December ( P <0.05). ② Compared to the control treatment, the effects of nitrogen deposition on CH 4 fluxes at N1, N2, and N3 were increased by 64.51%, 30.23%, and 80.57%, respectively, whereas the CH 4 fluxes under different treatments were not significantly different ( P >0.05). ③ There was significant positive correlation between CO 2 and CH4 fluxes and soil temperature ( P <0.05), however, the CO 2 and CH 4 fluxes were not significant with regards to soil pH and soil EC ( P >0.05).

Using the EPA method, emission of volatile organic compounds (VOCs) , sampled from barbecue, Chinese and Western fast-food, Sichuan cuisine and Zhejiang cuisine restaurants in Beijing was investigated. VOCs concentrations and components from different cuisines were studied. The results indicated that based on the calibrated baseline ventilation volume, the VOCs emission level from barbecue was the highest, reaching 12.22 mg · m(-3), while those from fast-food of either Chinese or Western, Sichuan cuisine and Zhejiang cuisine were about 4 mg · m(-3). The components of VOCs from barbecue were different from those in the other cuisines, which were mainly propylene, 1-butene, n-butane, etc. The non-barbecue cuisines consisted of high concentration of alcohols, and Western fast-food contained relatively high proportion of aldehydes and ketones organic compounds. According to emission concentration of baseline ventilation volume, barbecue released more pollutants than the non-barbecue cuisines at the same scale. So, barbecue should be supervised and controlled with the top priority.

To address effect of the sludge compost-containing medium on the growth of Manila lawn and environment quality, a pot experiment was conducted using six treatments based on contrasting sludge compost addition volume ratios in the soil system (i. e., 0% , 10% , 25% , 50% , 75% and 100%). The results indicated that the growth potential of Manila lawn was increased with increasing sludge compost addition volume ratio. The content of Hg in Manila plant was significantly positively correlated with that in the lawn medium. Although the contents of Cr, Cd and Hg in the lawn medium were synchronously increased with increasing sludge compost addition volume ratio in the soil system, their contents were all lower than the critical levels of third-class standard in the National Soil Environmental Quality Standard. The heavy metal and nitrate concentrations detected in percolating water were significantly positively correlated with those in the lawn medium, respectively. When the sludge compost addition volume ratio was more than 50% in this study, both heavy metal and nitrate concentrations in percolating water would exceed the maximum allowable levels of the National Groundwater Environment Quality Standard.

Biodegradation of nonylphenolic estrogens in soil and sludge-amended soil were investigated. Biodegradations of nonylphenol (NP), nonylphenol monoethoxylate (NPEO1) and nonylphenol diethoxylates (NPEO2) followed the first-order kinetics, and the degradation rates were enhanced when the temperature was increased. Spiked NP, NPEO1 and NPEO2 (with the concentration of 100, 50 and 100 mg x kg(-1), respectively) could be degraded completely in 45 days at the temperature of 30 degrees C. NP presented a higher degradation rates in soil than NPEO1 and NPEO2 under the same condition. The amended sludge enhanced the biodegradation of NPEO1 and NPEO2 in soil, while it inhibited that of NP.