海州湾岩芯沉积物稀土元素特征与物源分析

通过对海州湾潮滩HZ02岩芯沉积物中稀土元素的地球化学特征进行分析,以期探讨其物质来源。结果表明:HZ02岩芯中稀土元素平均值为225.36×10-6; 稀土元素类型特征表现为轻稀土富集而重稀土相对亏损、δEu中等程度亏损、δCe为弱的负异常; 岩芯沉积物稀土元素配分模式与陆源沉积物的稀土配分模式十分相似,可能暗示海州湾潮滩沉积物来源主要受陆源影响和控制。而且,1958年以前沉积物主要来源于临洪河,其次为废黄河,1958年以后,由于修建石梁河水库,临洪河物质减少。     

粤北山区相对贫困村的脱贫潜力评价及类型划分——以连州市为例

贫困村的脱贫能力直接影响脱贫工作的成效,研究发达省份欠发达地区相对贫困村的脱贫潜力问题有助于确保我国脱贫任务的全面完成。论文以广东省欠发达地区粤北连州市为例,从村级尺度出发分析其相对贫困村的基本特征,进而构建脱贫潜力评价体系,借助层次分析法和熵权法共同确定评价因子权重,利用加权求和方法完成连州市66个相对贫困村的脱贫潜力等级评价,并利用脱贫制约因素得分划分脱贫潜力类型。结果表明：1）连州市的相对贫困村自然区位条件较差,经济基础非常薄弱,耕地资源相对匮乏,受政策约束影响较大,空间分布呈集聚型;2）脱贫潜力评价指标体系包括自然区位、资源条件、经济因素、社会保障和设施配套等5个要素层共22个因子,其中权重占比最大的是经济因素和设施配套的6个因子;3）脱贫潜力评价结果划分为5个等级,其中属于脱贫潜力中等以上的相对贫困村占65.15%,说明连州市相对贫困村的脱贫潜力总体情况较好;4）脱贫潜力类型划分中,优先脱贫型占16.67%,稳步脱贫型占28.79%,重点帮扶型占54.54%。研究结果能为地方政府制定精准的脱贫策略提供科学有效的支撑与指引。     

Effects of biochars on the bioaccessibility of phenanthrene/pyrene/zinc/lead and microbial community structure in a soil under aerobic and anaerobic conditions

The immobilization of co-contaminants of organic and inorganic pollutants by biochar is an efficient remediation strategy. However, the effect of biochar amendments on the bioaccessibility of the co-contaminants in dry versus flooded soils has rarely been compared. In batch experiments, bamboo-derived biochar(BB) had a higher sorption capacity for phenanthrene(Phe)/pyrene(Pyr)/zinc(Zn) than corn straw-derived biochar(CB), while CB had a higher sorption capacity for lead(Pb) than BB. After 150 days of incubation, the amendments of 2% CB, 0.5% BB and 2% BB effectively suppressed the dissipation and reduced the bioaccessibility of Phe/Pyr by 15.65%/18.02%, 17.07%/18.31%and 25.43%/27.11%, respectively, in the aerobic soils. This effectiveness was more significant than that in the anaerobic soils. The accessible Zn/Pb concentrations were also significantly lower in the aerobic soils than in the anaerobic soils, regardless of treatments.The Gram-negative bacterial biomass and the Shannon–Weaver index in the aerobic soil amended with 2% CB were the highest. The soil microbial community structure was jointly affected by changes in the bioaccessibility of the co-contaminants and the soil physiochemical properties caused by biochar amendments under the two conditions. Therefore, dry land farming may be more reliable than paddy soil cultivation at reducing the bioaccessibility of Phe/Pyr/Zn/Pb and enhancing the soil microbial diversity in the short term.     

山区高速公路空间郁闭度对驾驶员视觉及生理指标的影响

为了解高速公路空间郁闭度对驾驶员视觉行为和心理状态的影响规律,在山区高速公路开展室外实车试验,采用Dikablis眼镜式眼动仪和Varioport生理记录仪记录了驾驶员的眼动和生理数据,包括注视时间百分比、平均注视时间、扫视幅度、眨眼率、心电、心率、皮电等。结果表明,随空间郁闭度增加,驾驶员皮电和扫视幅度增大,眨眼率和平均注视持续时间减小,视点越来越集中。随着驾驶员的逐渐适应,空间环境对驾驶员的心理影响逐渐减弱。驾驶员主要关注中间靠左区域,目标物为中央分隔带和前方道路。开敞空间下驾驶员对右侧区域有少量关注。半郁闭空间下驾驶员皮电呈现规律性的波动,对于左侧区域的关注明显增多,对右侧区域的注视持续时间较长,视点集中点更远。     

区域物质流规模结构分析评价方法及应用研究

生态经济体系中环境的引导和调控作用是经济系统物质代谢的重要组成部分.为了更为完善地分析评价经济发展和环境压力的关系,在输入端、输出端物质流规模和结构分析中侧重于物质隐藏流的综合计算,并以广州市南沙区为例进行实证研究.研究结果表明:南沙区域出口与出口物质隐藏流呈逐步上升趋势;南沙区的区内生产过程排放呈现"先降后增、总体递增"的趋势,今后南沙区应加强对工业生产过程中工业固废和二氧化硫排放的监控.     

SimuLink模拟活性污泥工艺的研究

以数学软件matlab内嵌的SimuLink工具箱为研究工具,结合国际水协( IWA)提出的活性污泥一号模型(ASM1)对欧盟科学技术合作计划(COST)提供的AO标准工艺流程建立数学模型并加以模拟,将模拟结果和COST提供的标准模拟结果进行比较,在各级反应器内的两者结果基本匹配,认为模型的建立、模拟结果合理可靠,基于该工艺模型的拓展模型和变型可进一步为实际工艺的设计与运行提供参考。     

过硫酸盐氧化与水泥固化稳定化协同修复苯胺污染土壤

为了快速高效地处理突发性事故造成的苯胺污染土壤,在水泥固化稳定化苯胺污染土壤时加入过硫酸盐和活性炭,评估固化稳定化产物中苯胺的浸出特征和降解机理. 结果表明:①过硫酸盐的加入可以快速有效地去除污染土壤中高浓度(10 g/kg)的苯胺,当反应时间为10 min、过硫酸盐添加量为1.0 eq(即过硫酸盐与土壤中苯胺的摩尔浓度比为1.0)时,处理后土壤中苯胺残留量为1 345 mg/kg;过硫酸盐添加量为2.0 eq时,苯胺残留量为43 mg/kg,反应时间对苯胺的去除效率影响不大,碱性条件有利于苯胺的降解. ②过硫酸盐-活性炭-水泥复合固化稳定化剂可以有效固化稳定化高浓度苯胺污染土壤,过硫酸盐的加入可以有效氧化土壤中的苯胺,是浸出液中ρ(苯胺)降低的主要因素;活性炭的加入可以进一步吸附残留的苯胺及降解产物,使浸出液中ρ(TOC)大幅降低;水泥水化产生的强碱性和温度升高有助于过硫酸盐对苯胺的氧化降解. ③苯胺氧化降解产物分析发现,偶氮苯、苯酚和联苯胺是苯胺的主要降解产物.      

三峡库区水环境风险评估与预警平台总体设计与应用

为保障三峡库区水环境安全,提高环保部门的环境预警和应急科学处置能力,根据“平战结合”的平台建设思路,提出了基于面向服务(SOA)可扩展的架构、Webservice数据服务调用模式和模块化功能的平台构建技术,集成了地方环保业务系统的成果,设计和实施了一个体系、一张网、一张图、一张表、一个流程的“五个一”平台工程,研发了集污染源风险识别、环境预警监控、模拟预测、应急评估处置和信息发布5项功能为一体的三峡水环境风险评估与预警平台,并在重庆市环保部门实现了业务化运行应用. 平台研究成果可支撑应急管理和日常管理,并在一系列突发性事件中得到业务应用验证和应用,环境应急响应时间从1~2 h缩短至10~20 min,应急处置时间从原来的1~2 d缩短至1~2 h,显著提高了三峡库区水环境风险评估、预警和防范能力.      

富硫沉积生境中微生物群落的垂直分布特征

为探讨富硫沉积环境中特定微生物类群对硫循环的贡献,人工建立富含硫酸盐的模型,对模型中各种环境化学参数进行监测,并采用不依赖于培养的微生物分子生态学技术对微生物群落垂向分布特征进行解析.结果表明,以沉积物-水界面为分界线,上层水相为好氧环境,硫化物浓度较底;而沉积物相中硫化物浓度较高,为厌氧生境.微生物群落分布与环境特征具有很好的吻合性,沉积物相中微生物群落相似性较高,多样性相对较低,而水相中微生物多样性较高,且与沉积物中微生物分离距离较大.在水-沉积物垂向剖面中,细菌域中的变形菌门(Protebacteria)(丰度为7.6%~32.8%)、绿弯菌门(Chloroflexi)(13.6%~22.3%)以及古菌域中的广古菌门(Euryarchaeota)(19.3%~29.2%)是微生物群落中的绝对优势类群.在该生境中,存在微生物主导的硫循环过程,在厌氧沉积物表层,δ变形菌纲(Deltaprotebacteria)中的硫酸盐还原细菌还原硫酸盐产生硫化物,同时降解有机质.硫化物向上层扩散时,被Thiobacillus、Acidithiobacillus和Halothiobacillus等属的硫氧化微生物氧化为单质硫,并进一步氧化为硫酸盐,在硫循环过程中有机质被逐渐降解.特定微生物种群的富集需要在不同的环境因素,多种微生物共同参与硫循环过程,完成有机质降解.     

Reducing nitrogen runoff from paddy fields with arbuscular mycorrhizal fungi under different fertilizer regimes

Nitrogen(N) runoff from paddy fields serves as one of the main sources of water pollution. Our aim was to reduce N runoff from paddy fields by fertilizer management and inoculation with arbuscular mycorrhizal fungi(AMF). In northeast China, Shuangcheng city in Heilongjiang province, a field experiment was conducted, using rice provided with 0%, 20%, 40%, 60%, 80%,and 100% of the local norm of fertilization(including N, phosphorus and potassium), with or without inoculation with Glomus mosseae. The volume, concentrations of total N(TN),dissolved N(DN) and particulate N(PN) of runoff water were measured. We found that the local norm of fertilization led to 18.9 kg/ha of N runoff during rice growing season, with DN accounting for 60%–70%. We also found that reduction in fertilization by 20% cut down TN runoff by 8.2% while AMF inoculation decreased N runoff at each fertilizer level and this effect was inhibited by high fertilization. The combination of inoculation with AMF and 80% of the local norm of fertilization was observed to reduce N runoff by 27.2%. Conclusively, we suggested that the contribution of AMF inoculation combined with decreasing fertilization should get more attention to slow down water eutrophication by reducing N runoff from paddy fields.