三峡蓄水期间汉丰湖消落区营养状态时间变化

为探明三峡蓄水后汉丰湖消落区水质营养状态的变化特征,于2013年10月至2014年2月对水质进行连续观察,测定了水质物理参数、营养盐与叶绿素(Chl-a)的质量浓度.结果表明,水体中营养盐与Chl-a质量浓度的增加,在淹水后营养程度有升高现象,2014年2月与2013年10月相比,TN、TP、高锰酸盐指数与Chl-a质量浓度分别增加了4.7、1.0、0.2、3.27倍,TN、TP质量浓度均超过藻类生长限值,随滞留时间延长易造成水体富营养化,应引起重视.Chl-a单因子评价反映出水质由贫营养向富营养演变.TN/TP结果表明,TN、TP分别在不同时间内制约着藻类的生长;2013年10~12月与2014年2月,藻类生长受TN限制;2014年1月,藻类生长受TP限制.Chl-a与p H、DO、NH+4-N、NO-3-N、TN、高锰酸盐指数及TP呈显著正相关,而与SD、水温呈显著负相关;蓄水期间,水质受到了同一污染源的影响.因子分析结果表明,汉丰湖消落区水质主要受p H、DO、NO-3-N、TN的影响,同时Chl-a、TP、NH+4-N与好氧性有机物的污染不可忽视;在蓄水稳定初期水体具有自净能力,随蓄水滞留时间的延长,水质污染程度整体上呈现逐步恶化的趋势,应加以控制;三峡蓄水期间,南河、东河营养程度相对较高,应加强治理.     

南京北郊春季气溶胶吸湿性分析

大气气溶胶的吸湿性对气溶胶粒子的谱分布、云凝结核形成、气候强迫、人体健康等均有重要的影响.利用吸湿性串联差分迁移率分析仪(HTDMA)在2014年4月16日~5月21日对南京北郊的大气气溶胶吸湿特性进行观测.30~230 nm气溶胶粒子在90%相对湿度下的吸湿增长观测结果表明,气溶胶粒子的吸湿增长因子平均概率分布函数(GF-PDF)呈现明显的双峰分布,即一个占主导地位的强吸湿模态,和一个相对较小但仍很明显的弱吸湿模态.对吸湿性的日夜对比分析发现,整体上白天的气溶胶粒子吸湿性大于夜间气溶胶粒子,白天强吸湿模态的粒子数目比例高于夜间,夜间气溶胶粒子的外混合程度更高.利用HYSPLIT模式对气溶胶来源分析结果表明,观测期间南京北郊主要受到3类气团的影响.其中西北大陆气团背景下爱根核模态粒子在经过大陆的长距离输送过程后,老化程度较高,吸湿性也更强.而对于积聚模态粒子,则为来自东方气团的粒子吸湿性更强,强吸湿模态粒子数目比例也较高.局地气团背景下气溶胶粒子在各粒径段都具有较高的强吸湿比例.     

Assessment of semi-natural habitats and landscape features on Irish farmland: New insights to inform EU Common Agricultural Policy implementation

Concerns over the loss of biodiversity and ecosystem services in farmland have prompted the development of agri-environment policy measures aimed at reducing farming pressure and maintaining semi-natural habitats in farmed landscapes. However, further knowledge is needed to guarantee successful agri-environment measures implementation. The current study assessed the quantity and the quality of semi-natural habitats in farms across a gradient of farming intensities in two contrasting regions in Ireland. Policy protection seemed fundamental for semi-natural habitats preservation. Habitats not protected by agricultural policy relied on extensive farming and are in danger of disappearing if they are intensified or abandoned. Due to the lack of policy incentives for habitat quality, no correlations were found between farming intensity and share of semi-natural habitats with habitat quality. Therefore, extensive farming and retention of habitats alone may not reverse the decline of farmland quality and biodiverisity and, thus, measures incentivising the environmental quality may be more successful.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01344-6) contains supplementary material, which is available to authorized users.     

Hydromorphological and socio-cultural assessment of urban rivers to promote nature-based solutions in Jarabacoa,Dominican Republic

In Latin America and the Caribbean, river restoration projects are increasing, but many lack strategic planning and monitoring. We tested the applicability of a rapid visual social–ecological stream assessment method for restoration planning, complemented by a citizen survey on perceptions and uses of blue and green infrastructure. We applied the method at three urban streams in Jarabacoa (Dominican Republic) to identify and prioritize preferred areas for nature-based solutions. The method provides spatially explicit information for strategic river restoration planning, and its efficiency makes it suitable for use in data-poor contexts. It identifies well-preserved, moderately altered, and critically impaired areas regarding their hydromorphological and socio-cultural conditions, as well as demands on green and blue infrastructure. The transferability of the method can be improved by defining reference states for assessing the hydromorphology of tropical rivers, refining socio-cultural parameters to better address river services and widespread urban challenges, and balancing trade-offs between ecological and social restoration goals.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01565-3.     

How effective are River Basin Management Plans in reaching the nutrient load reduction targets?

Riverine nutrient loads are among the major causes of eutrophication of the Baltic Sea. This study applied the Soil & Water Assessment Tool (SWAT) in three catchments flowing to the Baltic Sea, namely Vantaanjoki (Finland), Fyrisån (Sweden), and Słupia (Poland), to simulate the effectiveness of nutrient control measures included in the EU’s Water Framework Directive River Basin Management Plans (RBMPs). Moreover, we identified similar, coastal, middle-sized catchments to which conclusions from this study could be applicable. The first modelling scenario based on extrapolation of the existing trends affected the modelled nutrient loads by less than 5%. In the second scenario, measures included in RBMPs showed variable effectiveness, ranging from negligible for Słupia to 28% total P load reduction in Vantaanjoki. Adding spatially targeted measures to RBMPs (third scenario) would considerably improve their effectiveness in all three catchments for both total N and P, suggesting a need to adopt targeting more widely in the Baltic Sea countries.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01393-x) contains supplementary material, which is available to authorized users.     

疫情下医疗废物的处置现状分析

2019年新冠疫情席卷全球,在疫情环境下,医疗废物大幅增多,全国各大城市纷纷出现医疗废物处置不当的现象。本文对国内外现状分析,在认知、设施、管理和监督四个方面发现存在一定的问题,通过加强教育、加大储备、完善机制和改善监管的建议,为提升医疗废物应急处置能力提供参考。     

长期暴露下纳米TiO2对厌氧颗粒污泥体系稳定性的影响

以厌氧颗粒污泥为研究对象,通过静态试验和连续流厌氧反应器,重点研究了长期暴露下纳米TiO_2在对厌氧产甲烷体系的影响及其在颗粒污泥中的归趋.结果表明,短期急性暴露于150 mg·g-1(以VSS计)的纳米TiO_2尽管会暂时减缓产甲烷速率,但产酸阶段及产甲烷阶段代谢产物总量不会明显受到影响,纳米TiO_2对厌氧颗粒污泥具有较低的急性毒性.反应器运行结果表明,纳米TiO_2的长期暴露可导致挥发性脂肪酸(VFAs)积累及生物气产量降低,产酸菌比产甲烷菌对纳米TiO_2的累积效应更加敏感,纳米TiO_2抑制机制可归因于"物理遮蔽"作用.出水中TiO_2的平均含量只有0.632 mg·L~(-1),绝大多数纳米TiO_2都被截留在了反应器中.FISH检测表明,厌氧颗粒污泥微生物的菌群结构有所变化,纳米TiO_2在反应器内的积累使得甲烷八叠球菌的丰度大幅增加了115.6%,其优势地位明显增强.长短期暴露试验的结果对比也说明,用短期暴露试验来说明纳米颗粒对厌氧体系的长期累积效应具有一定局限性,纳米TiO_2对厌氧颗粒污泥中微生物的负面影响需要较长时间的积累才会显现.本研究结果可为厌氧污水处理体系中纳米颗粒的潜在生态风险评价提供理论支持和参考依据.     

黄河岸边土壤中类二(口恶)英类多氯联苯污染现状及风险

研究了全黄河范围内40个国家重点控制断面岸边土壤样品中类二噁英类多氯联苯(dioxin-like polychlorinated biphenyls,DL-PCBs)的污染现状,并利用毒性当量法和健康风险评价模型定量描述黄河岸边土壤中DL-PCBs对沿岸居民的毒性风险、致癌风险和非致癌风险.结果表明,黄河岸边土壤中各采样断面岸边土壤中ΣDL-PCBs的含量(以dw计,下同)范围为:0.37~7.17 ng·g~(-1),均值为0.38 ng·g~(-1).毒性风险计算表明,黄河岸边土壤中DL-PCBs的毒性当量范围为:0.00~30.31 pg·g~(-1),均值是13.63 pg·g~(-1),基本不会对沿岸居民产生毒性风险;健康风险模型计算表明,黄河岸边土壤中DL-PCBs对儿童和成人的致癌风险、非致癌风险均未超过美国EPA规定的限值,基本不会产生明显的健康风险.相比而言,黄河中游沿岸居民更易受到DL-PCBs危害.     

应用相平衡分配法建立湘江衡阳段沉积物重金属质量基准

采集湘江衡阳段29个站点的表层沉积物样品,测定沉积物中4种重金属(Cu、Pb、Zn和Cd)含量及赋存形态、以及孔隙水中重金属含量,根据相平衡分配法的基本理论,考虑参与沉积物-水相平衡分配的重金属组成,实测法计算重金属的沉积物-水相平衡分配系数(Kp),分别引用美国EPA制定保护水生生物不受重金属慢性毒性影响的基本连续浓度(CCC)和我国地表水环境质量标准(GB 3838-2002)Ⅰ类水质标准,建立两种湘江衡阳段沉积物重金属质量基准(SQC)进行对比分析,其中基于美国CCC建立的湘江衡阳段沉积物重金属质量基准与国内外研究成果相比可比性较好,4种重金属(Cu、Pb、Zn和Cd)的SQC值分别为64.62、55.57、1 360.40和2.34μg.g-1,此SQC具有保护长期生活于沉积物中的底栖生物不受重金属慢性毒性影响的意义.通过单因子评价法将湘江衡阳段沉积物中重金属总量与沉积物质量基准值(SQC)进行比较,结果表明,湘江衡阳段沉积物中Cd和Pb含量水平对底栖生物具有较大的慢性毒性影响,Cd污染不容忽视.     

制革废水和印染废水的综合毒性评估及鉴别

研究采用成组生物毒性试验(发光菌急性毒性、斑马鱼幼鱼急性毒性,斑马鱼胚胎发育毒性和小球藻急性毒性),结合理化指标,通过毒性单位、平均毒性(average toxicity,Av Tx)、毒性指数(toxic print,Tx Pr)、最敏感的测试(most sensitive test,MST)和潜在毒性效应指数(potential ecotoxic effects probe,PEEP)对不同工艺阶段印染及制革废水进行毒性削减评估.结果表明PEEP能兼顾废水排放量与毒性效应,更为客观地表征了废水综合毒性,PEEP评价结果显示制革废水和印染废水的毒性削减率分别达到36.8%和23.2%.最后,以发光菌作为受试生物,采用毒性鉴别评估(toxicity identification evaluation,TIE)技术,对印染废水进行毒性鉴别.结果表明,印染废水中主要的致毒物质为非极性有机污染,其次为可滤性化合物,然后是重金属、氧化性物质以及挥发性物质.