抚仙湖沉积物有机碳埋藏特征及来源解析

为探讨近百年来抚仙湖不同湖区沉积物中有机碳埋藏及其来源变化特征,以抚仙湖南北部沉积柱为研究对象,分析有机碳埋藏速率时空变化特征,利用正构烷烃及其分布特征对埋藏在沉积物中的有机碳来源进行解析.结果显示,抚仙湖沉积物中有机碳含量为1.79~29.39mg/g,有机碳埋藏速率为3.07~27.71g/（m²·a）,两者均随时间的增加呈现整体上升的趋势,1980年以来增长速度明显加快;沉积物中有机碳含量北部（8.70mg/g）小于南部（12.59mg/g）,但有机碳埋藏速率北部（13.54g/（m²·a））大于南部（8.29g/（m²·a））,这与抚仙湖南北部有机质来源类型及人类活动的加剧造成的流域环境变化有关;抚仙湖沉积物中正构烷烃碳数范围为C₁₂~C₃₃,整体以高碳数组分为主,奇偶优势明显,表明沉积物中有机质主要来源于高等植物,Paq指示水生植物中以沉水植物占主导优势,2C₃₁/（C₂₇+C₂₉）与ACL_27~33指示陆生高等植物来源中,草本植物与木本植物的贡献相当,水生植物在北部湖区贡献大于南部,陆生高等植物在南部湖区的贡献大于北部.     

基层监测站环境应急监测现状和建议

介绍目前环境应急监测的发展现状,以及对今后应急监测建设的建议。     

城市污水管网污染物沉积与冲刷释放规律研究

为明确城市污水管网中污染物沉积、冲刷释放及微生物降解作用对有机物去除的贡献,以管网中城市污水为研究对象,通过建立有沉积与无沉积的模拟管道,在首次冲刷的理论基础上得到管道污染物沉积释放计算模型,进而研究了不同流量下有机污染物的沉积与冲刷释放规律,并对不同流量下进出水的粒径分布及颗粒组成进行分析。结果表明,在管道6 h水力循环条件下,当流速为0.32 m/s时,污水中有机物变化以沉积贡献为主;当流速增加为管网最小设计流速0.6 m/s时,污染物沉积现象得到显著改善,冲刷释放效应增强;当流速进一步增加为0.9 m/s时,冲刷释放成为主要作用,生物降解作用微弱。     

Environmental,health, and safety department reorganization and prioritization: Using analytical hierarchy process to mitigate scope creep

Our objectives in this article are twofold: first, to use the analytical hierarchy process (AHP) to establish core priorities and, second, to discuss how to reorganize an environmental, health, and safety (EHS) department in a manner that will avoid “scope creep,” as well as inconsistencies in the delivery of client services as a result of personnel loss or change. The approach we describe is novel because it allows users to prioritize their actions daily and annually to recalibrate priorities.     

龙门山地区的地震系列及对未来地震的预测

龙门山地震带及其附近有三类地震系列,它们是小震系列、强震系列与大震系列,都满足前震系列公式:Ni=Ni-k/(1-b)k(其中N为地震频度,i为脚指数,k为方次,b为地震频度的变化率)。该公式的意义在于由已知的地震频度推导出未知频度,进而推导出地震的发生周期。使用该公式预测龙门山地震带未来大震发生的时间是十分有意义的。     

Deciphering urban traffic impacts on air quality by deep learning and emission inventory

Air pollution is a major obstacle to future sustainability, and traffic pollution has become a large drag on the sustainable developments of future metropolises. Here, combined with the large volume of real-time monitoring data, we propose a deep learning model, iDeepAir, to predict surface-level PM_2.5 concentration in Shanghai megacity and link with MEIC emission inventory creatively to decipher urban traffic impacts on air quality. Our model exhibits high-fidelity in reproducing pollutant concentrations and reduces the MAE from 25.355 µg/m³ to 12.283 µg/m³ compared with other models. And identifies the ranking of major factors, local meteorological conditions have become a nonnegligible factor. Layer-wise relevance propagation (LRP) is used here to enhance the interpretability of the model and we visualize and analyze the reasons for the different correlation between traffic density and PM_2.5 concentration in various regions of Shanghai. Meanwhile, As the strict and effective industrial emission reduction measurements implementing in China, the contribution of urban traffic to PM_2.5 formation calculated by combining MEIC emission inventory and LRP is gradually increasing from 18.03% in 2011 to 24.37% in 2017 in Shanghai, and the impact of traffic emissions would be ever-prominent in 2030 according to our prediction. We also infer that the promotion of vehicular electrification would achieve further alleviation of PM_2.5 about 8.45% by 2030 gradually. These insights are of great significance to provide the decision-making basis for accurate and high-efficient traffic management and urban pollution control, and eventually benefit people's lives and high-quality sustainable developments of cities.     

泰山顶与济南市大气臭氧浓度变化规律研究

利用2003年7月至9月在泰山顶和济南市3个月的臭氧（O3）自动连续监测数据,对两地O3浓度的频率分布、日变化和日际变化等特征进行对照分析。实验结果表明,泰山顶O3小时平均浓度频率分布比较集中,济南市O3小时平均浓度频率分布比较分散。泰山顶各月O3小时平均浓度的平均值和日均值均高于济南市;泰山顶O3小时平均浓度的最大值低于济南市,而O3小时平均浓度的最小值要高于济南市。泰山顶O3小时平均浓度日变化规律与济南市O3小时平均浓度日变化规律有很大差别,泰山顶O3小时平均浓度日变化很平缓,最大值与最小值相差不大,济南市O3小时平均浓度一般在中午和午后浓度较高,早晨和夜晚较低。     

大庆贴不贴泡周边土壤及地下水石油烃污染规律

贴不贴泡是大庆某石油化工总厂生产废水排放场地,其作用相当于一个水面较大的氧化塘.在纳污泡周边分别采集土壤及地下水样品,以研究其对周边土壤及地下水的污染状况.结果显示:纳污泡附近地下水及表层土壤受到不同程度石油烃污染,但除第1个采样点外,其余各采样点污染程度随距离变化不明显;土壤纵向以40～60cm厚度层污染最为严重.说明大庆地区草甸黑土对石油烃滞留能力很强,使石油烃在其中的迁移速度很低,特别是水平迁移速度更小,才使污染近30年的场地地下水受到的石油烃污染不是十分严重.表层土壤的污染主要是由于雨季纳污泡内污水溢出造成的.      

Biochar reduces cadmium accumulation in rice grains in a tungsten mining area-field experiment: effects of biochar type and dosage,rice variety,and pollution level

Environmental Geochemistry and Health - Cadmium (Cd)-contaminated rice (Oryza sativa) in Southern China is a great threat to food security, and the paddy soil remediation is urgently needed to...     

近34年祁连山南坡植被覆盖变化与气象因子关系研究

基于1982~2015年GIMMS NDVI数据，通过趋势线法和相关性分析方法，对祁连山南坡植被覆盖变化及影响因素进行分析。研究结果表明：（1）祁连山南坡植被覆盖整体呈显著上升趋势，线性回归增速为0.99%/10 a；各季节平均NDVI依次为夏季>秋季>春季>冬季， NDVI变化斜率排序依次为冬季>夏季>秋季>春季； NDVI月变化趋势基本一致，夏季NDVI在2004~2015年最大。（2）近34年来，祁连山南坡大部分区域属于常绿区域，三时间阶段植被增加面积整体表现出增加-减少-增加趋势，且在2004~2015年之间植被增加面积最大，占比为92.66%，增加速度最快的区域在门源县境内。（3）在影响因素方面，研究区NDVI与气温的相关性（0.58）大于降雨的相关性（0.27），研究区生长季 (4~9月)植被覆盖受气温和降水共同影响。