长江流域武汉段典型湖泊中微塑料的的赋存特征及生态风险评估

塑料污染在环境中具有普遍性,对生态系统具有潜在的风险性,为新兴的全球性环境问题。武汉境内江河纵横、百湖密布,是全球同纬度地区和长江中下游湖泊型湿地的典型代表。调查了武汉湖泊表层水体中微塑料的分布特征,并采用生态风险指数 (RI) 评估了微塑料的生态风险。结果表明,微塑料丰度为2 000~7 733 items·m⁻³,远城区湖泊表层水体微塑料丰度通常高于城乡结合区湖泊,中心城区微塑料丰度具有显著差异。湖泊中微塑料以纤维状为主,其次是碎片状,大小以<1 mm的小颗粒为主,主要颜色为透明和蓝色,主要成分为聚乙烯 (PE) 、聚丙烯 (PP) 和聚对苯二甲酸乙二醇酯 (PET) 。武汉市典型湖泊表层水体中MPs生态风险指数为601.5~8 954,均属于危险或高危等级,且PE、PP和PET的生态风险指数普遍较高。该研究结果可为城市湖泊中微塑料污染治理提供参考。     

Insight into the dynamic microbial community and core bacteria in composting from different sources by advanced bioinformatics methods

Microbial communities are important for high composting efficiency and good quality composts. This study was conducted to compare the changes of physicochemical and bacterial characteristics in composting from different raw materials, including chicken manure (CM), duck manure (DM), sheep manure (SM), food waste (FW), and vegetable waste (VW). The role and interactions of core bacteria and their contribution to maturity in diverse composts were analyzed by advanced bioinformatics methods combined sequencing with co-occurrence network and structural equation modeling (SEM). Results indicated that there were obviously different bacterial composition and diversity in composting from diverse sources. FW had a low pH and different physiochemical characteristics compared to other composts but they all achieved similar maturity products. Redundancy analysis suggested total organic carbon, phosphorus, and temperature governed the composition of microbial species but key factors were different in diverse composts. Network analysis showed completely different interactions of core bacterial community from diverse composts but Thermobifida was the ubiquitous core bacteria in composting bacterial network. Sphaerobacter and Lactobacillus as core genus were presented in the starting mesophilic and thermophilic phases of composting from manure (CM, DM, SM) and municipal solid waste (FW, VW), respectively. SEM indicated core bacteria had the positive, direct, and the biggest (>?80%) effects on composting maturity. Therefore, this study presents theoretical basis to identify and enhance the core bacteria for improving full-scale composting efficiency facing more and more organic wastes.

     

混凝-超滤工艺处理饮用水厂滤池反冲洗水和排泥水的效能

为探究饮用水厂滤池反冲洗水和排泥水的直接回用和处理后回用对水厂的影响及两类水处理过程中的差异,采用了污染负荷计算、实验室混凝小试和现场混凝-超滤中试装置对两类生产废水分别进行了研究。溶解性有机碳(dissolved organic carbon,DOC)、氨氮 (NH₄⁺-N)、Al³⁺和全氟类化合物(perfluorinated compounds,PFASs)的污染负荷计算结果表明生产废水直接回用会为水厂带来一定的额外负荷,其中排泥水和反冲洗水分别对PFASs和Al³⁺负荷贡献较大;通过对小试中浊度,UV₂₅₄以及5种荧光组分去除效果的对比,反冲洗水的混凝效果稍好于排泥水,同时10 mg·L⁻¹的聚合氯化铝为最佳混凝剂方案;在中试过程中,两类水中的浊度、有机物、Al³⁺和PFASs均可被有效去除,出水差异较小,但反冲洗水中的亲水性和小分子有机物使得其去除效果低于排泥水。总体来说,经过处理之后,两类生产废水均可回用,回用可有效减少废水排放量,提高水厂水资源利用率。     

Assessing economic sustainability and ecological efficiency with genuine progress indicator: a case study of the Yangtze River Delta from 2000 to 2018

To achieve urban sustainability, it is critical to enhance the environment, economy, and society simultaneously. This study adopted the revised genuine progress indicator (GPI) and ecological footprint (EF) to evaluate the ecological efficiency and economic sustainability of the Yangtze River Delta from 2000 to 2018. Spatial analysis was utilized to identify spatial autocorrelation. A total of 27 cities were then partitioned through k-means cluster analysis. The results showed that GPI and ecological efficiency improved rapidly, but economic sustainability showed a downward trend. GPI and GDP had a high degree of spatial correlation, especially in Suzhou-Wuxi-Changzhou Metropolitan Area. However, no spatial correlation existed between GPI and EF. The city with high GEE can reach 3000 $/gha, indicating the city consumed 1 global hectare to create $3000 of genuine economic growth. Shanghai, Hangzhou, and Taizhou were cities with the highest level of economic sustainability and ecological efficiency. The spatiotemporal characteristics of economic sustainability and ecological efficiency revealed in this study will provide theoretical guidance for alleviating ecological pressure and promoting economic sustainable development.

     

Simulation of global warming potential (GWP) from rice fields in the Tai-Lake region,China by coupling 1:50,000 soil database with DNDC model

Quantifying greenhouse gas (GHG) emissions from wetland ecosystems is a relatively new issue in global climate change studies. China has approximately 22% of the world's rice paddies and 38% of the world's rice production, which are crucial to accurately estimate the global warming potential (GWP) at regional scale. This paper reports an application of a biogeochemical model (DeNitrification and DeComposition or DNDC) for quantifying GWP from rice fields in the Tai-Lake region of China. For this application, DNDC is linked to a 1:50,000 soil database, which was derived from 1107 paddy soil profiles compiled during the Second National Soil Survey of China in the 1980–1990s. The simulated results show that the 2.34 Mha of paddy soil cultivated in rice–wheat rotation in the Tai-Lake region emitted about ?1.48 Tg C, 0.84 Tg N and 5.67 Tg C as CO₂, N₂O, and CH₄ respectively, with a cumulative GWP of 565 Tg CO₂ equivalent from 1982 to 2000. As for soil subgroups, the highest GWP (26,900 kg CO₂ equivalent ha^?1 yr^?1) was linked to gleyed paddy soils accounting for about 4.4% of the total area of paddy soils. The lowest GWP (5370 kg CO₂ equivalent ha^?1 yr^?1) was associated with submergenic paddy soils accounting for about 0.32% of the total area of paddy soils. The most common soil in the area was hydromorphic paddy soils, which accounted for about 53% of the total area of paddy soils with a GWP of 12,300 kg CO₂ equivalent ha^?1 yr^?1. On a regional basis, the annual averaged GWP in the polder, Tai-Lake plain, and alluvial plain soil regions was distinctly higher than that in the low mountainous and Hilly soil regions. As for administrative areas, the average annual GWP of counties in Shanghai city was high. Conversely, the average annual GWP of counties in Jiangsu province was low. The high variability in soil properties throughout the Tai-Lake region is important and affects the net greenhouse gas emissions. Therefore, the use of detailed soil data sets with high-resolution digital soil maps is essential to improve the accuracy of GWP estimates with process-based models at regional and national scales.     

承包商 HSE 管理体系运行存在问题及对策

分析了承包商HSE管理体系的运行现状,针对存在的问题,提出了管理措施。     

13X分子筛对水体中钒离子的吸附

为研究分子筛对水体中重金属的吸附效果,选取了13X分子筛作为实验材料,研究其对钒离子的吸附效果。分别研究了在不同温度、时间、溶液pH值和初始钒浓度的条件下,13X分子筛对钒离子的吸附量,结果表明：酸性条件更利于13X分子筛对钒的吸附,溶液pH≥5时吸附量趋于0;随着反应温度的升高,13X分子筛对钒离子的吸附量逐渐增加;13X分子筛对钒离子的吸附符合Langmuir模型和拟二级动力学模型。13X分子筛对钒离子具有一定的吸附效果,在一定的处理工艺条件下,可作为水体钒污染的修复材料。但针对不同来源废水的特点,需对分子筛进行改性并进一步优化修复工艺条件以实际应用。     

反应条件对等离子体脱除吸附于Cu-Ce/AC表面NOx的影响

以放电等离子体协同催化法对吸附在Cu-Ce/AC上的NOx进行脱除,研究了不同的放电条件和添加水蒸气对脱除NOx的影响。结果表明,对于同轴圆筒形反应器,催化剂量一定时,放电长度增加,吸附态NOx去除率先升高后下降;放电电压增大,吸附态NOx去除率升高,原因在于放电反应区内能量密度和活性粒子分布状态改变。根据NOx程序升温脱附（TPD）,TPD低温位（x更容易被放电等离子体脱除,放电长度和放电电压能够影响不同吸附位上NOx的去除效率。适宜条件下,吸附态NOx去除率最高达到93.3%。循环吸附-等离子体脱除NOx进行10次后,NOx脱除率在92%以上。在混合气中添加5%水蒸气提高了等离子体对吸附态NOx的去除率,但导致循环吸附-等离子体脱除NOx效率下降。原因是H2O与NOx竞争吸附带来的负面效应大于等离子体中H2O提供自由基与吸附态NOx反应所带来的正面效应。     

改性木屑吸附除亚甲基蓝性能

为提高对亚甲基蓝的去除效果,采用热解+NaOH浸泡方法制备了改性木屑,用SEM研究了改性对木屑表面结构的影响,并以该改性木屑为吸附剂,进行了从水溶液中吸附亚甲基蓝的性能研究。研究结果显示,改性木屑表面光滑,并出现多发熔孔。常温下,改性木屑对亚甲基蓝的吸附等温线符合Langmuir方程,最大吸附量322.58 mg/g,是原始木屑的10倍,是活性炭的3倍,改性效果显著;对浓度为200 mg/L、pH值为7的亚甲基蓝溶液,改性木屑投加量为0.8 g/L时,去除率达到了99.01%,去除效果理想。吸附动力学符合伪二级速率方程。     

表面活性剂增效电动技术修复多环芳烃污染土壤

研究了电动修复过程中修复时间和表面活性剂Triton X-100、鼠李糖脂对多环芳烃芘污染土壤的修复效果的影响。结果表明,在电动修复过程中,随着修复时间的增加,芘的去除率相应提高。通过向电解液中添加表面活性剂Triton X-100,芘的去除率从11.64%提高到了23.42%,当在电解液中添加浓度为40倍CMC的鼠李糖脂后去除率升高至36.29%,阳极附近土壤甚至达到了92.49%,这表明Triton X-100和鼠李糖脂均能促进土壤中芘的溶解和迁移,鼠李糖脂的促进作用高于Triton X-100。