Langhoffklausen0629

To investigate the level of polybrominated diphenyl ether (PBDE) contamination in the automobile microenvironment, air and dust samples were collected from 15 family automobiles in Hangzhou City, China. The PBDE concentrations, distribution of congeners, and human exposure were determined; and the content and distribution of PBDEs in automotive interior materials were analyzed. The results revealed that the average and median concentrations of ∑14PBDEs in the air in automobiles were 732 and 695 pg/m3, respectively, whereas those in automotive dust were 4913 and 5094 ng/g, respectively. Decabromodiphenyl ether (BDE-209) had the highest proportion, accounting for 61.3% and 88.8% of the ∑14PBDEs in the air and dust, respectively. The potential primary sources of PBDEs in automobile air and dust were volatile polyurethanes in seat covers and foot pads, respectively. Human exposure calculations revealed that infants and toddlers in cars were most exposed to air and dust, respectively. BDE-47 and -99 were the primary sources of health risks related to air and dust in cars.Anaerobic fermentation is an eco-friendly technology for waste activated sludge (WAS) treatment, during which resource recycle can be achieved. However, traditional sludge anaerobic fermentation is limited by the poor efficiency. We herein reported a novel high-efficiency technology by combining freezing with potassium ferrate (PF) for sludge pretreatment to promote hydrogen production from anaerobic fermentation. Experimental results demonstrated that freezing coupled with PF pretreatment exerted positively synergetic effect on hydrogen production. The maximal hydrogen production of 12.50 mL/g VSS (volatile suspended solids) was detected in the fermenter pretreated by freezing (-12 °C for 24 h) coupled with PF at 0.15 g/g TSS (total suspended solids), which was 1.34, 2.33, and 7.91 times of that from the individual PF, individual freezing, and control fermenters, respectively. The simulation results based on the modified Gompertz model indicated that both the hydrogen production potential and rate were promoted by freezing coupled with 0.15 g/g TSS PF pretreatment, from 2.14 to 13.52 mL/g VSS and 0.012 to 0.163 mL/g VSS/h, respectively. Thorough mechanism investigations revealed that the sludge EPS (extracellular polymeric substances) and microbial cells were both effectively damaged by combined freezing and PF pretreatment, resulting in the acceleration of sludge disintegration. SP2509 Further investigations demonstrated that except for the acidogenesis, the other biochemical processes were all inhibited by freezing coupled with PF pretreatment, but the inhibitory extent for hydrogen consuming processes was more serious than that responsible for its generation. Gene sequencing analysis illuminated that both of the hydrolytic and hydrogen generating bacteria were largely enriched in the combined pretreatment fermenter. Moreover, the dewatering performances of fermented sludge were found to be notably enhanced by freezing coupled with PF pretreatment.In mountain pastures worldwide, studies investigating vegetation changes due to long-term grazing and environmental changes are sparse, especially regarding the effects of changes in snowmelt patterns. The outstanding availability of historical vegetation data from Kyrgyz mountain pastures creates unique opportunities to study past and forecast future changes, making them ideal model ecosystems. Using a resurvey approach, we explored the response of mountain vegetation to management and environmental changes in the Western Tien-Shan to investigate whether plant communities of six vegetation types (ecozones) had changed over 42 years, whether changes were related to management or ecological causes and whether species' mean elevational ranges had changed. We assembled historic vegetation data (1973-1987) in six ecozones that were resurveyed annually from 2008 to 2015 and connected them with species' management-related traits and ecological indicator values. Overall, a homogenization of vegetation within and amoer the response of the vegetation to environmental changes and promote alternative land-use options to maintain ecosystem functioning. In mountain ecosystems worldwide, the observed acceleration of changes might go unnoticed, calling for long-term studies and global climate-vegetation-management interaction models.Organic material (OM) applied to cropland not only enhances soil fertility but also profoundly affects soil nitrogen cycling. However, little is known about the relative contributions of soil ammonia-oxidizing archaea (AOA) and bacteria (AOB) to nitrous oxide (N2O) production during ammonia oxidation in response to the additions of diverse types of OMs in the tropical soil for vegetable production. Herein, the soils were sampled from a tropical vegetable field subjected to 4-year consecutive amendments of straw or manure. All the soils were amended with ammonium sulfate ((NH4)2SO4, applied at a dose of 150 mg N kg-1) and incubated aerobically for four weeks under 50% water holding capacity. 1-octyne or acetylene inhibition technique was used to differentiate the relative contributions of AOA and AOB to N2O production. Results showed that AOA dominated N2O production in soil managements of unfertilized control (CK), chemical fertilization (NPK), and NPK with straw (NPKS), whereas AOB contributed more in soil under NPK with manure (NPKM). Straw addition stimulated AOA-dependent N2O production by 94.8% despite the decreased AOA-amoA abundance. Moreover, manure incorporation triggered both AOA- and AOB-dependent N2O production by 147.2% and 233.7%, respectively, accompanied with increased AOA and AOB abundances. Those stimulating effects were stronger for AOB, owing to its sensitivity to the alleviated soil acidification and decreased soil C/N ratio. Our findings highlight the stimulated N2O emissions during ammonia oxidation by historical OM amendments in tropical vegetable soil, with the magnitude of those priming effects dependent on the types of OM, and appropriate measures need to be taken to counter this challenge in tropical agriculture ecosystems.