辽河源头区畜禽养殖粪便处理处理现状及对策初探

本文以畜禽养殖较为集中、污染问题较为突出的辽河源头区为研究区域,通过流域内畜禽污染物排放方式,污染物排放总量,总结流域内畜禽养殖污染特点,在次基础上提出切实可行的畜禽污染防治对策,为相关政策的制定提供依据。     

Environmental significance of biogenic elements in surface sediments of the Changjiang Estuary and its adjacent areas

Biogenic elements and six phosphorus(P) fractions in surface sediments from the Changjiang Estuary and adjacent waters were determined to investigate the governing factors of these elements, and further to discuss their potential uses as paleo-environment proxies and risks of P release from sediment. Total organic carbon(TOC) and leachable organic P(Lea-OP) showed high concentrations in the estuary, Zhejiang coast and ofshore upwelling area. They came from both the Changjiang River and marine biological input.Biogenic silicon(BSi) exhibited a high concentration band between 123 and 124°E. BSi mainly came from diatom production and its concentration in the inshore area was diluted by river sediment. Total nitrogen(TN) was primarily of marine biogenic origin. Seaward decreasing trends of Fe-bound P and Al-bound P revealed their terrestrial origins. Influenced by old Huanghe sediment delivered by the Jiangsu coastal current, the maximum concentration of detrital P(Det-P) was observed in the area north of the estuary. Similar high concentrations of carbonate fluorapatite(CFA-P) and CaCO3 in the southern study area suggested marine calcium-organism sources of CFA-P. TOC, TN and non-apatite P were enriched in fine sediment, and Det-P partially exhibited coarse-grain enrichment, but BSi had no correlation with sediment grain size. Diferent sources and governing factors made biogenic elements and P species have distinct potential uses in indicating environmental conditions. Transferable P accounted for 14%-46% of total P. In an aerobic environment,there was low risk of P release from sediment, attributed to excess Fe oxides in sediments.     

Recent advances in ionic liquids-based hybrid processes for CO2 capture and utilization

CO₂ capture and utilization (CCU) is an effective strategy to mitigate global warming. Absorption, adsorption and membranes are methods used for CO₂ separation and capture, and various catalytic pathways have also been developed for CO₂ utilization. Although widely researched and used in industry, these processes are energy-intensive and this challenge needs to be overcome. To realize further optimization, novel materials and processes are continuously being developed. New generation materials such as ionic liquids (ILs) have shown promising potential for cost-effective CO₂ capture and utilization. This study reviews the current status of ILs-based solvents, adsorbents, membranes, catalysts and their hybrid processes for CO₂ capture and utilization. The special properties of ILs are integrated into new materials through hybridization, which significantly improves the performance in the process of CCU.     

石家庄市PM_（2.5）的污染现状及防控对策

通过对石家庄市PM2.524 h质量浓度监测结果的分析,发现PM2.5的污染指数范围是84~242,污染指数最高点出现在高新区,最低点出现在封龙山。导致PM2.5高污染指数的影响因素有气象、地理、机动车保有量和石家庄工业结构。因此从减少扬尘、控制机动车尾气排放量、工业污染防治、环保及气象部门协作等方面提出了PM2.5的防控对策。     

Land Use and Climate Variability Amplify Carbon,Nutrient, and Contaminant Pulses: A Review with Management Implications

Nonpoint source pollution from agriculture and urbanization is increasing globally at the same time climate extremes have increased in frequency and intensity. We review >200 studies of hydrologic and gaseous fluxes and show how the interaction between land use and climate variability alters magnitude and frequency of carbon, nutrient, and greenhouse gas pulses in watersheds. Agricultural and urban watersheds respond similarly to climate variability due to headwater alteration and loss of ecosystem services to buffer runoff and temperature changes. Organic carbon concentrations/exports increase and organic carbon quality changes with runoff. Nitrogen and phosphorus exports increase during floods (sometimes by an order of magnitude) and decrease during droughts. Relationships between annual runoff and nitrogen and phosphorus exports differ across land use. CH₄ and N₂O pulses in riparian zones/floodplains predominantly increase with: flooding, warming, low oxygen, nutrient enrichment, and organic carbon. CH₄, N₂O, and CO₂ pulses in streams/rivers increase due to similar factors but effects of floods are less known compared to base flow/droughts. Emerging questions include: (1) What factors influence lag times of contaminant pulses in response to extreme events? (2) What drives resistance/resilience to hydrologic and gaseous pulses? We conclude with eight recommendations for managing watershed pulses in response to interactive effects of land use and climate change.     

探讨水文、气象因素对九江台形变资料的影响

利用九江台数字化形变观测资料,分析了形变各测项受温度、降雨、气压和水位等因素的影响情况。分析结果表明,年变动态较好的测项往往固体潮质量稍差、受降雨影响较小,且主要受控于洞温,而年变形态较差的测项往往受降雨影响明显;气压短期大幅波动对各测项有不同程度的影响;水位变幅较大时对大多数形变测项有显著影响。     

HpGe γ谱仪本底变化对环境样品放射性测量结果的影响

在环境样品测量过程中,本底涨落对天然核素测量结果的影响应根据其在谱仪中计数率的高低具体分析.用γ谱仪测量介质中天然放射性核素的活度浓度时,必然要进行本底谱的扣除,由此会带来一定的误差.对一台N型HpGe γ谱仪在8年间的23个本底谱进行了研究,并分析了本底涨落对测量结果的影响.研究发现,被测介质中天然放射性核素的活度浓度越低,本底涨落越大,由扣除本底引入的误差就越大.     

Enhancement of ultrasonic disintegration of sewage sludge by aeration

Sonication is an effective way for sludge disintegration,which can significantly improve the efficiency of anaerobic digestion to reduce and recycle use of sludge.But high energy consumption limits the wide application of sonication.In order to improve ultrasonic sludge disintegration efficiency and reduce energy consumption,aeration was introduced.Results showed that sludge disintegration efficiency was improved significantly by combining aeration with ultrasound.The aeration flow rate,gas bubble size,ultrasonic density and aeration timing had impacts on sludge disintegration efficiency.Aeration that used in later stage of ultrasonic irradiation with low aeration flow rate,small gas bubbles significantly improved ultrasonic disintegration sludge efficiency.At the optimal conditions of 0.4 W/m L ultrasonic irradiation density,30 m L/min of aeration flow rate,5 min of aeration in later stage and small gas bubbles,ultrasonic sludge disintegration efficiency was increased by 45% and one third of ultrasonic energy was saved.This approach will greatly benefit the application of ultrasonic sludge disintegration and strongly promote the treatment and recycle of wastewater sludge.     

Effects of Ca(OH)2 assisted aluminum sulfate coagulation on the removal of humic acid and the formation potentials of tri-halomethanes and haloacetic acids in chlorination

The effects of addition of calcium hydroxide on aluminum sulphate(or alum) coagulation for removal of natural organic matter(NOM) and its subsequent effect on the formation potentials of two major types of regulated disinfection byproducts(DBPs),haloacetic acids(HAAs) and trihalomethanes(THMs),have been examined.The results revealed several noteworthy phenomena.At the optimal coagulation pH(i.e.6),the coagulation behavior of NOM water solutions versus alum dose,showed large variation and a consequent great change in the formation potentials of the DBPs at certain coagulant doses.However,with addition of a relatively small amount of Ca(OH) 2,although the zeta potential of coagulated flocs remained almost the same,NOM removal became more consistent with alum dose.Importantly,also the detrimental effect of charge reversal on NOM removal at the low coagulant dose disappeared.This resulted in a steady decrease in the formation potentials of DBPs as a function of the coagulant dose.Moreover,the addition of Ca(OH) 2 broadened the pH range of alum coagulation and promoted further reduction of the formation potentials of the DBPs.The enhancement effects of Ca(OH) 2 assisted alum coagulation are especially pronounced at pH 7 and 8.Finally,synchronous fluorescence spectra showed that the reduction in DBPs formation potential by Ca(OH) 2-assisted alum coagulation was connected to an enhanced removal of small hydrophobic and hydrophilic HA molecules.Ca(OH) 2-assistance of alum coagulation appeared to increase substantially the removal of the hydrophilic HA fraction responsible for HAAs formation,prompting further reduction of HAA formation potentials.