1984～2017年太湖岛屿的动态变化及驱动因子分析

近些年来,围堰、跨区域调水、清淤等人类活动导致太湖中的岛屿面积的变化及其边界的迁移。基于Landsat遥感影像探究太湖内岛屿面积的变化趋势及边界的迁移方向,一定程度上反映人为因素对岛屿动态变化的的影响,进而指导太湖治理工作。通过波段分析、非监督分类以及分类后处理的方法从Landsat影像中提取岛屿信息,获得1984～2017年不同时期的岛屿面积和边界数据,并对岛屿面积和边界数据进行动态变化趋势的分析,最终结合从文献、年鉴和其他与太湖相关资料中总结的与太湖岛屿相关的人为活动信息分析引起太湖主要岛屿动态变化的原因。研究表明:小贡山、漫山岛和三山岛屿总面积均呈下降趋势,但下降程度与年际间波动幅度不同,岛屿面积变化的人为驱动因素可归纳为清淤和旅游开发,自然驱动因子为流水侵蚀;岛屿边界的迁移与"禁止围网养殖"、"湿地公园建设"等政策实施呈现显著相关性,且具体变化与政策颁布之间存在时间上的滞后性。     

Spatial distribution and ecological risk assessment of sediment metals in a highly industrialized coastal zone southwestern Taiwan

Spatial variations of Cr, Cu, Hg, Ni, Pb, and Zn in the surface sediments from 34 stations of the Kaohsiung coastal zone southwestern Taiwan were studied to address the current pollution status, sediment quality, and potential ecological risk. The study revealed that the concentrations of sediment metals in Kaohsiung Harbor were alarmingly high compared to the other region of Kaohsiung coast. The concentrations of Cr, Cu, Hg, Ni, Pb, and Zn in the harbor sediments were as high as 351, 247, 1.93, 61.8, 60.9, and 940 mg kg⁻¹, respectively. The current situation of metal pollution was assessed by different pollution indices and results showed moderate to severe enrichment of Cu, Hg, and Zn in the harbor sediments. According to the degree of contamination, pollution load index, and contamination severity index, the sediments from the inner Kaohsiung Harbor show high degree and high severity of metal contamination, while the rest of Kaohsiung coastal areas show uncontaminated or low-level pollution. Results of mean ERM quotient and potential ecological risk index also indicated that the harbor sediments posed a 49% probability of biological toxicity and very high ecological risk. The toxic units indicated that the negative biological effects of the six metals in the harbor sediments were Zn > Cu > Cr > Ni > Hg > Pb. In contrast to Kaohsiung Harbor as a trap where considerable amount of anthropogenic metal loadings accumulated in sediments, low metal concentrations were observed in most Kaohsiung coastal sediments. It probably resulted from the limited fine-grained sediment deposition. In the wave-dominated Kaohsiung coastal zone, fine-grained sediments associated with polluted metals tend to be easily resuspended and transported offshore via waves and wave-induced currents. The results of this study can provide valuable information for river and coastal zone management.

     

The associations of air pollution exposure during pregnancy with fetal growth and anthropometric measurements at birth: a systematic review and meta-analysis

Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air...     

千岛湖水源水微生物安全性评价

千岛湖作为国家战略水源地,其微生物安全直接关系到千万居民的用水安全.为了研究千岛湖湖水的生物安全性,于2018-2019年采集了金竹牌取水口不同深度的水样,并检测了水样的可生物降解溶解性有机碳(BDOC)、细菌再生长的潜力(BGP)、可培养细菌数、潜在的条件致病菌和细菌群落结构.结果显示,千岛湖水质属地表水Ⅱ～Ⅲ类水,...     

尿素基纤维的制备及对水中Cu2+和Cd2+的吸附

以棉纤维为原料,经氯化和取代反应,制得尿素基纤维并用于水中Cu^2＋和Cd^2＋的吸附,考察了各种因素对吸附效果的影响。尿素基纤维对Cu^2＋和Cd^2＋的吸附可用Langmuir等温吸附方程描述,吸附过程可看成单层吸附。较佳吸附条件：重金属离子溶液pH为5,流量为7mL／min。用过的尿素基纤维经2mol／L的盐酸洗脱再生后,对Cu^2＋的吸附、解吸、再吸附的性能良好,可重复使用。     

钢渣吸附Pb2+的动力学研究

采用批式振荡吸附法研究了钢渣吸附Pb^2＋的动力学。研究结果表明,钢渣吸附Pb^2＋的动力学控制步骤（简称动力学控制步骤）随实验条件的变化而变化：钢渣粒径大于120μm、振荡器转速小于150r/min或Pb^2＋初始质量浓度小于150mg/L时,孔扩散是动力学控制步骤;钢渣粒径小于120μm、振荡器转速大于150r/min或Pb^2＋初始质量浓度大于150mg/L时,表面扩散是动力学控制步骤;钢渣对Pb^2＋的吸附反应是二级反应,其吸附速率为13.26g/（mg.min）。     

流动注射分光光度法测定水中铝的含量

以桑色素作显色剂,采用流动注射分光光度法测定水中铝的含量。在桑色素质量浓度为0．8g／L、聚氧乙烯辛基苯基醚体积分数为1．0％、进样环体积为400μL、检测波长420nm的条件下,采用流动注射分光光度法对水中铝的含量进行测定,本方法的线性范围为2～300μg／L,检出限（信噪比为3）为0．124μg／L,相对标准偏差为2．9％,加标回收率为96．4％～101．8％。     

超声强化高级氧化技术降解水中有机污染物的研究进展

介绍了用于降解水中有机污染物的超声强化技术,分析了超声与臭氧氧化、Fenton试剂氧化和光催化氧化等高级氧化技术联用的机理,综述了这些联用技术在降解有机污染物方面的研究进展,并展望了超声强化高级氧化技术的发展前景。     

砷华废渣的综合利用

采用氧化焙烧-软锰矿浆吸收、磁化焙烧-磁选、酸浸工艺处理砷华废渣.氧化焙烧的适宜条件为焙烧温度650 ℃,焙烧时间60 min,废渣粒径97 μm.磁化焙烧的适宜条件为焙烧温度550 ℃,焙烧时间30 min.酸浸的适宜条件为硫酸质量分数20%.经全流程实验,硫以MnSO4*H2O的形式回收,产品质量达到工业级硫酸锰一级标准.铁回收率为84.8%,锌回收率为80.9%,处理后废渣中银含量达246 g/t.处理过程产生的废弃物中砷较为稳定.     

厌氧-好氧生物反应器填埋工艺特性研究

基于生物反应器填埋技术,研究1种填埋场地循环操作的厌氧-好氧生物反应器填埋工艺,设计了该工艺模拟装置并研究了其运行工艺特性.厌氧阶段主要通过渗滤液回灌控制反应器工艺条件,主要试验结果为,pH值,R1在 6周后可上升至6.7～7.8,R2在17周内一直低于6.8;渗滤液COD浓度,R1在13周时下降至10?617 mg/L,R2在5周后上升至60?000 mg/L后长期趋于稳定;填埋气累计产量,R1在8周达到44%,R2几乎不产气.衡量稳定化可以分别采用渗滤液pH、COD浓度及BOD₅/COD的减少率、填埋气的累计产率等指标来判断,并据此转换为好氧填埋运行.好氧阶段主要是通过强制通风来减少恶臭和水分,主要试验结果为,通风19d氨气浓度降为1.16 mg/m³,通风23d后恶臭浓度降为19;通风14d后含水率降为26%.完成此阶段的工艺指标值可依据矿化垃圾开采的最终用途确定.对主要试验数据进行了数值模拟.厌氧-好氧填埋过程的微生物演替经RISA分析,有4个优势菌群,一些兼性菌群在厌氧-好氧阶段起着重要的承前启后作用.