砷超富集植物蜈蚣草中磷和钙的亚细胞分布及其与耐砷毒的关系

为了在研究砷超富集植物蜈蚣草中磷和钙的亚细胞分布,并探讨其与蜈蚣草耐砷毒的关系进行了试验研究.结果表明,蜈蚣草吸收的磷主要分布在胞质组分中(平均占各部位总磷含量的44%以上),吸收的钙主要分布在细胞壁组分中(平均占各部位总钙含量的48%以上).与低钙(0.03和2.5 mmol·L-1)处理相比,高钙(5.0 mmol·L-1)处理时,根部的胞质组分和叶柄的细胞器组分中磷含量较高.各器官的亚细胞组分中钙含量随着介质中添加钙浓度的提高而增加.介质钙浓度过高会抑制蜈蚣草的生长.在加砷处理下,根部和叶柄细胞壁组分的磷含量有所减少,但地上部细胞器组分的磷含量及其含磷总量占植株含磷总量的相对比例、根部细胞壁组分的钙含量增加.蜈蚣草自主调节磷和钙的亚细胞水平分布可能是其耐砷毒的机制之一.     

Dynamic phosphorus budget for lake-watershed ecosystems

Lake eutrophication caused by excess phosphorus （P） loading from point sources （PS） and nonpoint sources （NPS） is a persistent and serious ecological problem in China. A phosphorus budget, based on material flow analysis（MFA） and system dynamic （SD）, is proposed and applied for the agriculture-dominated Qionghai Lake watershed located in southwestern China. The MFA-SD approach will not only cover the transporting process of P in the lake-watershed ecosystems, but also can deal with the changes of P budget due to the dynamics of watershed. P inflows include the fertilizer for agricultural croplands, soil losses, domestic sewage discharges, and the atmospheric disposition such as precipitation and dust sinking. Outflows are consisted of hydrologic export, water resources development, fishery and aquatic plants harvesting. The internal P recycling processes are also considered in this paper. From 1988 to 2015, the total P inflows for Lake Qionghai are in a rapid increase from 35.65 to 78.73 t/a, which results in the rising of P concentration in the lake. Among the total P load 2015, agricultural loss and domestic sewage account for 70.60% and 17.27% respectively, directly related to the rapid social-economic development and the swift urbanization. Future management programs designed to reduce P inputs must be put into practices in the coming years to ensure the ecosystem health in the watershed.     

Removal of nitrogen and phosphorus in a combined A2/O-BAF system with a short aerobic SRT

A bench-scale anaerobic/anoxic/aerobic process-biological aerated filter （A^2/O-BAF） combined system was carded out to treat wastewater with lower C/N and C/P ratios. The A^2/O process was operated in a short aerobic sludge retention time （SRT） for organic pollutants and phosphorus removal, and denitrification. The subsequent BAF process was mainly used for nitrification. The BAF effluent was partially returned to anoxic zone of the A^2/O process to provide electron acceptors for denitrification and anoxic P uptake. This unique system formed an environment for reproducing the denitdfying phosphate-accumulating organisms （DPAOs）. The ratio of DPAOs to phosphorus accumulating organisms （PAOs） could be maintained at 28% by optimizing the organic loads in the anaerobic zone and the nitrate loads into the anoxic zone in the A^2/O process. The aerobic phosphorus over-uptake and discharge of excess activated sludge was the main mechanism of phosphorus removal in the combined system. The aerobic SRT of the A^2/O process should meet the demands for the development of aerobic PAOs and the restraint on the nitrifiers growth, and the contact time in the aerobic zone of the A^2/O process should be longer than 30 min, which ensured efficient phosphorus removal in the combined system. The adequate BAF effluent return rates should be controlled with 1--4 mg/L nitrate nitrogen in the anoxic zone effluent of A^2/O process to achieve the optimal nitrogen and phosphorus removal efficiencies.     

曝气-过滤一体化装置脱氮除磷的研究

曝气-过滤一体化装置将生物反应器与过滤机理有机结合，较好地维持了反应器中的高污泥浓度，实现了水力停留时间（HRT）与污泥停留时间的分离。采用连续流间歇曝气工艺对该装置的脱氮除磷效果进行了研究。实验结果表明：在HRT为8h，运行方式为曝气2h、停曝2h的条件下，COD去除率为95．55％，NH3-N未检出，TN为84．90％，TP为93．69％，出水各项指标都达到了GB8978-1996（污水综合排放标准》一级排放标准要求。     

高效除磷材料的除磷特性研究

研究了高效除磷材料(Efficient Phosphorus Removal Composite,EPRC)的除磷特性,以及以此材料为填料的吸附柱对模拟含磷废水的除磷效果.试验结果表明: EPRC颗粒在15℃、25℃、35℃时的最大饱和吸附量分别达到1.9535mg/g、2.281mg/g、3.6724mg/g.以EPRC颗粒填充吸附柱处理模拟含磷废水时,停留时间8h、连续进水、运行8d,磷的平均去除率为93%,废水pH值略有升高.     

微生物对芦苇人工湿地除磷影响研究

以上海梦清园人工芦苇湿地为对象，在微生物制剂使用的同时研究了微生物对湿地除磷效果的影响。经过对近一年的数据分析表明，微生物的增加使总磷平均去除率达到20．9％，高于空白的18．3％。微生物的磷酸化作用使得出水磷更多以磷酸根形式表达，甚至使磷酸盐含量不降反升。底泥监测表明，微生物制剂的加入能有效的促进浮泥层中磷的转移，减缓浮泥层中磷的积累，10个月后试验组浮泥层的磷含量相对空白对照组可降低10％以上，菌剂对于减缓磷的积累，促进磷向基质转移有重要意义。     

通榆河南段控制单元最大日负荷估算及分配研究

以通榆河南段控制单元为研究区，利用现有的平原感潮河网区水量模型、面源污染负荷统计模型和水环境容量模型，估算研究区2010年污染物最大日负荷总量（TMDL），并进行负荷削减和分配研究。结果表明：研究区COD、氨氮（NH3-N）90％保证率（2004年）下的水环境容量分别为7．76万t,0．37万t；xCN2010年污染物入河量，COD、NH3-N的最大年负荷分别为1．99万t,0．28万t。在研究区涉及的各县市中，海安、姜堰、东台是负荷削减的重点区域；对于不同的污染源，城镇生活点源和农业面源是研究区污染物总量控制的关键。     

Altitude profiles of total chlorinated paraffins in humus and spruce needles from the Alps (MONARPOP)

Chlorinated paraffins (CPs) are toxic, bioaccumulative, persistent, and ubiquitously present in the environment. CPs were analyzed in humus and needle samples, which were taken within the Monitoring Network in the Alpine Region for Persistent and other Organic Pollutants (MONARPOP) at sampling sites of 7 different altitude profiles in the Alps. Gas chromatography combined with electron ionization tandem mass spectrometry (EI-MS/MS) was used for the determination of total CPs (sum of short, medium and long chain CPs). CPs were found in all samples; the concentrations varied between 7 and 199 ng g⁻¹ dry weight (dw) and within 26 and 460 ng g⁻¹ dw in humus and needle samples, respectively. A clear vertical tendency within the individual altitude profiles could not be ascertained. Within all altitude profiles, elevated concentrations were observed in humus samples taken between 700 and 900 m and between 1300 and 1500 m. In the needle samples no similar correlation could be observed due to higher variation of the data.     

Effect of Earthworm（Pheretima sp.） Density on Revegetation of Lead/zinc Metal Mine Tailings Amended with Soil

The objective of this study was to investigate the effects of earthworm density on the availability of nutrients and heavy metals in metal contaminated soils. Pb/Zn mine tailings were mixed throughly with a red yellow podzolic soil at the ratio （w/w） of 75：25. Earthworms （Pheretima sp.） were introduced to the mixture at four different densities, zero, three, six and nine individuals per pot planted with ryegrass （Loliun multiflorum）. The results indicated that earthworm activity significantly enhanced ryegrass shoot biomass. However, as denser earthworm population was introduced, shoot biomass tended to decrease. Earthworm activity significantly increased soil pH and availability of N, P and K in the tailings and soil mixture. There was a general tendency that uptake of Zn by ryegrass increased after earthworm inoculation, although the increase in extractable Zn in tailings and soil mixture was not significant. On the contrary, there seemed to be a lower uptake of Pb by ryegrass under earthworm inoclation, despite the fact that higher extractable Pb concentrations were observed. The present project indicated that the improved growth of ryegrass was due to improved nutrient availability and other soil conditions, by inoculation of earthworms at an appropriate rate. Further studies are needed to illustrate the relationship between metal availability and earthworm activity in the field.     

A GIS-based Study for Optimizing the Total Emission Control Strategy in Lanzhou City

A geographic information system (GIS)-based approach with spatial analysis advantages was developed to optimize the total emission control scheme on air pollution in Lanzhou, combined with Models-3 modeling system and a linear programming model. GIS system is mainly used for establishing a multifactor assessment model to quantitatively divide environmental functional zone, and also used for selecting control sites in linear programming model. The results show that most of the urban area belongs to the second type of function, which is 122.8 km² occupying about 76.5% and the third type of about 32.9 km² occupying 20.5%. To reach the air quality up to the national standard in the entire control area, some large-emission factories need to cut emissions from 19% to 27%. For small but low-emission height sources, the cut may be as high 40%. The improvement of the ecological environment is urgently needed for controlling the background particle pollution in Lanzhou city.