Mining activities have led to significant rare earth elements (REEs) contamination and ecotoxicological risks in aquatic systems. However, the concentration, speciation, and primary controlling factors of REEs in aquatic systems in southwest China have remained unclear. This study investigated the water geochemistry, concentration, speciation, fractionation patterns, and anomalies of REEs in the surface water, shallow groundwater, and deep groundwater within a mining-impacted catchment area in southwest China across different seasons. REE concentrations were in the range of 1.12–73.66 μg/L in surface water, 0.09–96.58 μg/L in shallow groundwater, and 0.09–1.05 μg/L in deep groundwater. Seasonal variations significantly impacted REE concentrations in surface water and shallow groundwater. The variability of environmental parameters, driven by higher temperatures during the wet season, significantly controlled the increases in the proportions of dissolved REE in both surface water and groundwater. The water recharge between surface water and groundwater resulted in analogous REE fractionation patterns and anomalies. Variation in pH, oxidation-reduction potential, iron, manganese and aluminum content in water influenced the fractionation indices of REEs. Cerium and europium anomalies in water samples provided insights into REE sources and associated hydrological dynamics. Our results demonstrate that REE fractionation patterns and anomalies were influenced by water-rock interactions, mining activities and hydrogeological factors, which facilitates a comprehensive understanding of the hydrogeochemistry process in aqueous systems.

The growing demand for rare earth elements (REEs), in particular neodymium, dysprosium, europium, and terbium, by producers of electric vehicles and smartphones boosted their global excavation, causing serious soil and groundwater pollution hazards. Their mitigation by soil phytoremediation became very popular by merits of low cost and sustainability, but its mechanisms and effects on microbial communities and characteristics of soils co-contaminated by REEs, fluoride (F), and heavy metals (HMs) still need to be clarified and optimized. This study investigated plant community structure and collected soil sample from the natural, artificial restoration areas and bastnäsite tailings area. Utilizing advanced high-throughput sequencing technology, bacterial and fungal communities in five soil samples were analyzed. The results showed that phytoremediation could reduce the content of soil REEs and F and the mobility of lead (Pb), promoting soil stability, especially by shrub and herbs. Woody-shrub-herbs co-planting could significantly improve soil microbial diversity compared to natural restoration sites. The predominant species were identified as Proteobacteria and Ascomycota. The changes of soil nutrients and the stabilization of Pb remarkably affected the shift in the microbial communities. The findings strongly indicate that woody-shrub-herb co-planting was the optimal vegetation pattern among the three restoration measurements for controlling REEs-F-HMs co-contamination pollution and enhancing soil stability by mitigating or stabilizing soil pollutants, altering soil composition, and increasing microbial diversity.

本文着眼乡村振兴的国家战略,紧扣地方发展总体要求和奋斗目标,契合学校"十四五"发展规划,落实"立德树人"根本任务,强化课程思政引领,在广泛调研产业需求基础上,建立匹配凉山产业发展的优势专业集群,创建"专业融合"人才培养体系,搭建政产学研多方共育平台,在培养卓越"四新"专业融合型人才方面取得较好成效,以期为民族地区人才培养提供参考.

随着我国稀土资源开发和利用,稀土元素对水生生态环境的影响及其生态风险越来越受关注.本文以稀土镧的通用敏感生物急性半致死/效应浓度(half lethal/effect concentration,L(E)C50)和慢性无观察效应浓度(no observed effect concentration,NOEC)数据,分别采用评价因子法和物种敏感度分布法(species sensitivity distribution,SSD)推导计算了镧的预测无效应浓度(predicted no effect concentration,PNEC),比较不同数据类型和计算方法的结果差异及不确定性,并以四川安宁河为例进行了水生态风险表征.采用评价因子法推导的急性和慢性PNEC分别为1.180μg·L-1和4.000μg·L-1.由急性数据拟合SSD曲线推导的PNEC为42.770μg·L-1,通过急慢性比(acute to chronic ratio,ACR)转换的PNEC为2.032 μg·L-1.在慢性数据缺乏的情况下,ACR-SSD是相对可行的方法.安宁河镧的水生态风险评价结果表明,所有调查断面均处于中等以上生态风险,其稀土污染问题应引起重视.

Heavy metal air pollution poses a serious threat to human health and the environment in Chinese tourist cities. In this study, we investigated the temporal and spatial variations of atmospheric heavy metal pollution using moss bags in Xichang, a tourist destination in Southwest China. The biomonitoring investigation used an indigenous moss (Taxiphyllum taxirameum) transplanted into bags. Moss bags were exposed to 22 sites including industrial, agricultural, urban/residential, tourist, and high-traffic sites, across four different seasons in 2019–2020. The results showed that T. taxirameum was a good biomonitor of air pollution in Xichang. Among the 22 sample points, air pollution was the worst along the G102 motorway. Heavy metal emissions varied in different regions and directions. Temporal changes significantly influenced the heavy metals accumulated in moss bags, with low deposition of most elements observed at nearly all sampling sites in summer. Different seasons and regions were important factors affecting atmospheric heavy metal pollution. Based on the correlation analysis and the positive matric factorization model, the results revealed that heavy metals in moss bags in Xichang were mainly derived from anthropogenic sources and atmospheric deposition. Overall, this research provides an important reference for air pollution monitoring in urban areas.

微生物气溶胶广泛存在于大气中,其在雾霾天的形成和发展等方面扮演了重要的角色.梳理了雾霾期空气微生物气溶胶的分析鉴定、微生物气溶胶与雾霾天相关性方面的主要研究成果,得出如下结论:空气微生物气溶胶的分析鉴定应制定统一的检测标准,为雾霾天空气微生物的健康风险评估提供科学的定量指标;雾霾期空气微生物气溶胶的浓度普遍高于非霾期,主要表现为真菌气溶胶浓度增加,但微生物的种群丰富度并不会因污染程度的增加而增加;空气微生物气溶胶对人类健康构成重大威胁,应采取科学措施进行预防.

为考察四川省牦牛坪稀土矿区稀土、铅和氟复合污染对农田微生物群落功能多样性的影响,采用Biolog-ECO法分析稀土矿区高污染区(H区)和低污染区(L区)农田土壤根际与非根际微生物群落功能多样性特征及其与土壤理化性质的相关关系.结果 显示,不同污染区土壤微生物对31种碳源的利用能力存在显著性差异(P＜0.05),H区的非根际土壤微生物利用能力、多样性指数均最低,其AWCDi≥0.8的碳源仅1种,而根际土壤有27种,占总碳源的87.1％,植物生长显著促进根际细菌活性;而L区土壤根际与非根际微生物差异显著的碳源仅5种(P＜0.05).冗余分析(Redundancy Analysis,RDA)表明在非根际条件下稀土元素(REE)、铅、氟、碳氮比(C/N)与AWCD、Shannon指数等多样性指数呈负相关,其中REE贡献了87.4％的微生物群落特征解释率,是微生物群落变化的主要驱动因子.根际条件下4个环境因子仅解释了48％的特征值,说明植物的参与改变了污染物对微生物群落的影响.因此在高浓度稀土、铅和氟污染农田土壤采用植物和微生物联合修复措施效果较好,而在低浓度污染土壤植物生长对细菌的促进效果不显著,应考虑采用其他修复措施.

以西昌市康铜冶炼厂尾矿废弃地为例采用种子萌发实验研究了其土壤种子库特征,并与相邻生环境土壤种子库进行对比,以期为凉山地区铜冶炼废弃地恢复提供科学依据.结果表明:矿渣土共萌发3种植物,种子密度为350粒/m2.尾矿废弃地土壤共萌发5种植物,种子密度为375粒/m2,其中狗牙根占比最大.相邻生环境土壤共萌发6种植物,种子密度为300粒/m2.尾矿废弃地与相邻生环境土壤种子库相似性为0.400,与矿渣种子库相似性为0.857,与地上植被相似性为0.276,三者之间表现差异较大.尾矿废弃地土壤种子库的多样性指数平均值为1.116,多样性较低.

为了解西昌市大气重金属的污染状况,该研究于2019年4月-2020年4月分季节采用鳞叶藓(Taxiphyllum taxirameum)藓袋法对西昌市大气重金属污染进行了跟踪监测.在2020年1月15日-4月15日春季监测期中发生了COVID-19疫情和西昌"3.30"特大森林火灾等重大突发事件,对西昌市的大气生态环境产生了影响.通过对事件发生前后的藓袋中Al、Cr、Fe、Cu、Ni、Pb、Mn、Hg、Zn、V、As、Ba等12种重金属含量分析,结合西昌市大气监测数据、气象数据等,解析了森林火灾和COVID-19疫情对西昌市大气重金属污染的影响.结果表明,春季(2020年1月15日-4月15日)12种重金属的总富集量(12.85±1.57)mg/g显著高于其他3个季节(p＜0.01),但其他3个季节富集总量不存在显著性差异(p＞0.05),可见春季监测期富集量的大幅上升可能是受重大突发事件的影响.通过疫情前后空气变化比较,COVID-19疫情影响使西昌市机动车活动水平和排放量下降,旅游业相关区域大气Pb污染量下降.同时不平衡的污染物排放量下降引起了城区的大气氧化性显著上升,促进了二次颗粒物的生成,周边工业源的颗粒物传输进入城区,使工业区下风向的城市边缘区域的藓袋Hg富集量大幅上升.该研究表明藓袋法是一种有效的大气重金属污染生物监测方法,能够反映出对空气质量影响的重大事件的效应.

应现代化教育方式的改革的要求,学生的实验能力,动手能力,创新及解决问题的能力培养越来越受到学校领导及老师的重视.文章通过改革课程实验管理模式,让学生参与准备实验、预实验工作,课程实验课堂上实施"学生助教"制,大大提高学生的学习兴趣和学习效果.准备实验和预实验相当于新型开放性实验,不仅能提高实验室的使用效率,而且能提高实验员老师的管理效率.此种实验教学模式使学生的语言表达能力、操作技能、分析、解决问题的能力、创新能力等得到了不同程度的提高.

现代大学发展的主题是学科建设与发展,实验室则为学科建设提供基本保障.以民族地区应用技术型本科高校西昌学院为例,加强高校学科基地建设,需要打破固有的以专业、院系为基础的实验室建设模式,应依据人才培养、学科建设对实验室条件的需求,按照学科群将学校的教学科研仪器设备进行分类,加强实验室管理,提高仪器设备共享率,助力学科建设工作.

运用层次分析法及综合指标评价法,提出并建立了人工湿地综合评价指标体系,选取选址适宜性、构建、水质净化功能和经济社会效益4个一级指标及对应的15个二级指标作为评价指标.以邛海湿地五期内小河沟人工湿地作为探究对象,结果显示:小河沟人工湿地的综合评指数为7.38,处于"良",邛海人工湿地具有较好的水质净化功能,在选址及构建上处于良好水平,在运行管理上应加强垃圾清理和植被管理.

湿法氧化去除烟气Hg0过程中产物Hg2+易发生络合反应,络合产物可能改变氧化体系形成新反应机制,这一现象尚未被认识研究.为获得Hg2+络合物生成及其对烟气脱汞影响机理,研究了配体阳离子、配体浓度、反应pH值、反应温度和摩尔比等对Hg2+络合反应的影响和氧化去除烟气Hg0的络合反应机理.结果表明MgCl2、KCl、NiCl2和BaCl2配体均能与HgCl2形成络合物,而CuCl2和SnCl4则不能生成络合物.络合物生成量随配体浓度的增加先升高然后趋于平衡;络合反应在酸性环境下发生且不受pH值变化影响;碱性环境下络合反应不能进行;反应温度基本不影响络合反应效应;增加配体浓度可提高络合物产量,不同配体络合效应不同,但最大吸光度基本相同,为(4.20±0.03)A.配体对络合反应有响应区间,低于区间下限值时不能形成络合物,高于上限制值时络合物产量不随配体浓度而变化.HgCl2络合反应累积稳定常数β4=1015.07;[HgCl4]2-可螯合Hg(aq)和O2(aq)使其与ClO-和Hg2Cl2反应,形成氧化-络合氧化反应新机理.

Phosphorus stress of phytoplankton was determined by analysis of alkaline phosphatase activity during spring (April to May) in 2016 in river-lake and adjacent water system of Qionghai lake, including 6 major rivers, estuary and adjacent water around Qionghai lake. The result showed that there were obvious spatial heterogeneity in chlorophyll concentration and alkaline phosphatase activity of phytoplankton of the river-lake system of Qionghai in spring, indicating that different rivers and regions shows different phosphorus stress. Among all the study sites, the phosphorus stress was the highest in the Guan-ba river, and followed by estuary of Guanba river, estuary of Qing river and adjacent water of E’zhang river, while the ad-jacent water of Qing river showed the lowest phosphorus stress.

通过交换邛海湿地的两个典型地点的天然基质,并对交换培养后基质上的生物膜的藻类群落结构、 生物量、 叶绿素、 胞外酶活性、EPS多糖含量等指标进行分析,观察环境变化后生物膜结构功能随时间的改变情况.研究结果表明:生物膜在交换培养后,藻类结构、 叶绿素浓度、 胞外酶活性、 多糖含量等指标均发生改变.随着交换时间增长,生物膜均发生了一定变化,其变化符合生物膜群落生长特性和生物膜对环境的适应性规律,综合反映出邛海湿地生物膜对环境改变有明显的响应.

通过对西昌邛海滨湖公路5个不同路段在旱季和雨季降雨期间的有效采样,分析其路面径流的污染特征.结果表明,旱季SS和TN污染贡献率较大,分别为51.206％和24.008％;雨季的SS和C()D污染贡献率较大,分别为40.559％和22.058％;5个不同路段的路面径流污染程度均超过邛海湖泊功能的Ⅱ类水质要求,旱季和雨季的污染物浓度存在一定的差异,可能与不同路段的车流量、降雨强度、路面清扫程度以及自然气候等因素密切相关.本文结合其污染因素探讨有效的控制措施,并提出建议.

通过在雨季和旱季各2次典型降雨期间对邛海滨湖公路路面径流连续采样监测,结果表明,该路面径流的主要污染因子为SS、COD、TP、TN和Pb,旱季的径流污染程度较雨季重,主干路的路面径流污染最严重.因子分析表明,路面径流的主要污染因子为重金属和营养盐,其方差贡献率分别为64.546％和13.596％.潜在生态风险评估表明,路面径流中重金属平均潜在生态风险处于轻微级别,6种重金属中除Pb在主干路达到中等风险外,其余均为轻微风险.

生态环境监测在生态环境工作中具有基础性地位,以生态环境监测推动生态文明建设具有重要意义.本文从中共十九大关于生态文明建设的阐述入手,指出应全面理解和领会党中央对生态环境的决策部署,提出深入理解新时代生态文明建设与生态环境监测的关系、以中央生态环境监测决策部署为指引开展生态环境监测、以全面从严治党确保生态环境监测数据“真、准、全”的生态环境监测工作思路.

本研究采集安宁河干流的沉积物样品,分析了12种重金属元素As、Hg、Cr、Cu、Zn、Pb、Cd、Fe、Mn、Ba、Ti、V含量的空间变化,并采用了地累积指数法和潜在生态危害指数法评价其重金属污染分布现状.结果表明,沉积物中各种重金属均有不同程度的富集,重金属污染主要分布在矿业最为发达的中游河段及下游段,其中Ti、Ba、Mn、Cd、Zn地质累积指数较高,出现中度及以上污染;安宁河重金属平均潜在生态风险已达中等程度,存在较强的生态危害,其中Cd表现出强度的生态风险(Ei值为46.33～366.84),应引起重视.

通过分析中美两个国家的大学在培养学生成才方面的不同点与相似处,指出美国大学在学生事务工作方面存在着目标一致性、结构扁平化、队伍专业化、内容精细化、评价规范化的共同点,同时不同高校对同样的学生事务工作做法又各有特点,归纳了美国大学在学生事务工作方面的做法对国内大学的启示.