Microplastic pollution in surface water and sediments of Qinghai-Tibet Plateau: Current status and causes     

《China Geology》2021,4(1):178-184

To study the current status and causes of the microplastic pollution in surface water of the Qinghai-Tibet Plateau, this paper compared the average microplastic abundance in sediments and surface water of the Qinghai-Tibet Plateau and the results are as follows. First, the average microplastic abundance in surface water of the independent rivers and the whole area is 247–2686 items/m³ and 856 items/m³, respectively. The average microplastic abundance in sediments of independent rivers or lakes and the whole area is 0–933 items/m² and 362 items/m², respectively. Meanwhile, the degree of microplastic pollution in river sediments is higher than that in lake sediments, and the rivers suffering from microplastic pollution mainly include the Brahmaputra River, Tongtian River, and Nujiang River. Second, compared with the microplastic pollution in other areas of the world, the levelof microplastic pollution in the lakes and rivers of the Qinghai-Tibet plateau is not lower than that of well-developed areas with more intensive human activities. Finally, this study suggests that relevant government departments of the Qinghai-Tibet Plateau should strengthen waste management strategies while developing tourism and that much attention should be paid to the impacts of microplastics in the water environment.©2021 China Geology Editorial Office.  相似文献   

Sensitivity assessment of strontium isotope as indicator of polluted groundwater for hydraulic fracturing flowback fluids produced in the Dameigou Shale of Qaidam Basin          下载免费PDF全文

Zheng Zhao-xian  Cui Xiao-shun  Zhu Pu-cheng  Guo Si-jia 《地下水科学与工程》2021,9(2):93-101

Hydrogeochemical processes that would occur in polluted groundwater and aquifer system, may reduce the sensitivity of Sr isotope being the indicator of hydraulic fracturing flowback fluids(HFFF) in groundwater. In this paper, the Dameigou shale gas field in the northern Qaidam Basin was taken as the study area, where the hydrogeochemical processes affecting Sr isotope was analysed. Then, the model for Sr isotope in HFFF-polluted groundwater was constructed to assess the sensitivity of Sr isotope as HFFF indicator. The results show that the dissolution can release little Sr to polluted groundwater and cannot affect the εSr(the deviation of the 87 Sr/86 Sr ratio) of polluted groundwater. In the meantime, cation exchange can considerably affect Sr composition in the polluted groundwater. The Sr with low εSr is constantly released to groundwater from the solid phase of aquifer media by cation exchange with pollution of Quaternary groundwater by the HFFF and it accounts for 4.6% and 11.0% of Sr in polluted groundwater when the HFFF flux reaches 10% and 30% of the polluted groundwater, respectively. However, the Sr from cation exchange has limited impact on Sr isotope in polluted groundwater. Addition of Sr from cation exchange would only cause a 0.2% and 1.2% decrease in εSr of the polluted groundwater when the HFFF flux reaches 10% and 30% of the polluted groundwater, respectively. These results demonstrate that hydrogeochemical processes have little effect on the sensitivity of Sr isotope being the HFFF indicator in groundwater of the study area. For the scenario of groundwater pollution by HFFF, when the HFFF accounts for 5%(in volume percentage) of the polluted groundwater, the HFFF can result in detectable shifts of εSr(ΔεSr=0.86) in natural groundwater. Therefore, after consideration of hydrogeochemical processes occurred in aquifer with input of the HFFF, Sr isotope is still a sensitive indicator of the Quaternary groundwater pollution by the HFFF produced in the Dameigou shale of Qaidam Basin.  相似文献   

THE IMPACT OF MOUNTAIN TO BASIN WINDS ON THE DIURNAL VARIATION IN FOG OVER THE SICHUAN BASIN, CHINA     

张福颖  刘海文  朱玉祥  赵亮  段伯隆  傅宁 《热带气象学报(英文版)》2019,25(2):257-268

There is an increased demand for the accurate prediction of fog events in the Sichuan Basin (SCB) using numerical methods. A dense fog event that occurred over the SCB on 22 December 2016 was investigated. The results show that this dense fog event was influenced by the southwest of a low pressure with a weak horizontal pressure gradient and high relative humidity. This fog event showed typical diurnal variations. The fog began to form at 1800 UTC on 21 December 2016 (0200 local standard time on 22 December 2016) and dissipated at 0600 UTC on 22 December 2016 (1400 local standard time on 22 December 2016). The Weather Research and Forecasting model was able to partially reproduce the main features of this fog event and the diurnal variation in the local mountain to basin winds. The simulated horizontal visibility and liquid water content were used to characterize the fog. The mountain to basin winds had an important role in the diurnal variation of the fog event. The positive feedback mechanism between the fog and mountain to basin winds was good for the formation and maintain of the fog during the night. During the day, the mountain to basin wind displayed a transition from downslope flows to upslope flows. Water vapor evaporated easily from the warm, strong upslope winds, which resulted in the dissipation of fog during the day. The topography surrounding the SCB favored the lifting and condensation of air parcels in the lower troposphere as a result of the low height of the lifting condensation level.  相似文献   

内蒙古冬季极端多雪气候事件环流演变特征及季节预测信号     

高涛  乌兰  司瑶冰  关彦如  杨泽龙  任晓萌  张晓梅 《内蒙古气象》2019,(1):3-8,I0002

文章研究关注了内蒙古冬季极端多雪气候事件的季节预测问题,在对大量降水观测资料、海温及大气环流场资料进行统计、分析、研究的基础上,确定了历史上58a(1960—2017年)内蒙古冬季极端多雪和少雪气候事件样本,通过对大气环流场的对比分析发现极端多雪或少雪冬季环流场特征显著不同,分析后确定了影响内蒙古冬季降雪的主要环流系统,包括西太平洋副热带高压、极涡、东亚大槽、环流E型及南方涛动等系统。同时,探索了对这些主要环流系统具有预测意义的来自海洋和大气场的预测信号,对预测信号关键区做了标准化定量提取,确定了预测信号综合指数分段判别阈值,给出了预测概念模型,取得了较好预测效果。  相似文献   

苏州市一次重霾污染天气过程的数值模拟   总被引：1，自引：1，他引：0  

吴珂  包云轩  蔡敏  金建平  牛利  严明良 《气象科学》2019,39(1):104-116

本文对苏州地区2015年12月13—15日发生的一次典型的重霾污染天气过程进行了数值模拟,分析了颗粒物及其组分的时空变化特征及其气象影响因子,以期为该区域空气污染治理和预防提供科学依据。结果表明:(1)利用WRF-Chem模式对此次重霾污染天气过程的污染气体成分进行数值模拟后发现,小时平均的PM_(2.5)、PM_(10)、CO、SO_2、NO_2模拟值与实测值的相关系数较高,达到0.68以上,通过了P0.01的显著性检验,且日变化过程对应也较好。(2)通过分析此次污染过程的天气背景,发现污染形成期高空环流比较平直,中层为均匀的弱高压控制,地面受弱高压脊控制,这种形势容易导致颗粒物的堆积。后期地面等压线密集时,风速大,有利于污染物的输送与扩散。(3)通过分析此次污染过程期间气象要素的变化发现,有逆温、风速小、相对湿度大等不利的气象条件是导致此次污染过程发生的重要原因之一。(4)HYSPLIT轨迹分析显示,此次重霾过程主要受北方大范围灰霾颗粒物南下影响,北方污染气团逐步南推,14至15日本地大气扩散条件差、污染物累积,最终导致本地污染加重,从而发生重霾事件。(5)火点图的分布进一步验证了此次重霾污染过程是由外来污染气团输入所导致。  相似文献   

疏勒河流域极端水文事件对极端气候的响应     

程玉菲  程文举  胡想全  金彦兆 《高原气象》2019,38(3):583-592

为了明确疏勒河流域极端水文事件对极端气候事件的响应关系,选取疏勒河流域内及其周边的托勒、敦煌、瓜州、玉门、酒泉、马鬃山等气象站点的气温、降水和蒸发的日值数据,昌马堡水文站的日径流数据,通过趋势分析、滑动平均、主成分分析等方法,分析疏勒河流域极端气候指数、极端水文事件的年际变化规律以及影响极端水文事件的因素,并明确该流域极端洪水年内分布特征。结果表明:疏勒河流域年际气温升高趋势明显,降水量呈波动变化,增加趋势不明显,而蒸发量呈下降的变化趋势。表征高温的极端气温指数呈显著上升趋势,表征低温的极端气温指数呈显著下降趋势,说明疏勒河流域气温增幅明显。极端降水指数呈显著的增加趋势。该流域极端洪水事件和频次呈上升趋势,而极端枯水事件和频次呈下降趋势。极端洪水事件主要受控于极端降水事件,特别是极端降水总量,极端高温事件对极端洪水总量的增加也有影响,而极端枯水事件主要受控于极端低温事件。此外,2000-2016年年最大洪峰流量出现的时间有由8月向7月转变的趋势。  相似文献   

Household dependence on solid cooking fuels in Peru: An analysis of environmental and socioeconomic conditions     

《Global Environmental Change》2019

Solid fuel use is linked with adverse effects on the environment and human health. Yet, solid fuels remain an important energy source for households in developing countries. Even when country-level dependence on solid fuels is modest, there is often significant variation in within-country patterns of solid fuel use. This study examines a range of environmental and socioeconomic conditions to understand the relationship between them and household energy use within a country. While our results are derived from a study of regional patterns of solid fuel dependence in Peru, the contribution of this study is broad: variables that we include in our models of households’ fuel choice decisions are likely to shape such decisions in most developing countries. Our findings indicate that environmental conditions, such as elevation and forest cover, are associated with solid fuel use. Socioeconomic factors, including urbanization, poverty and female literacy, are similarly important. In addition, we identify nuanced links between types of female employment and indigenous population, on the one hand, and solid fuel use, on the other.  相似文献   

安徽贵池地区富硒土壤地球化学特征及开发利用潜力     

梁胜跃  徐明钻  刘建东 《江苏地质》2023,47(4):402-411

为了解安徽贵池地区富硒土壤特征与潜力,服务当地富硒土地资源开发,选择贵池西部开展土壤地球化学测量试验,探讨Se、I等有益元素的富集特征、成因及潜力,Cd、As等有害元素的超标特征及成因等,结合研究区土壤中有益、有害元素特征,讨论富硒土地资源及其开发优势。发现表层和深层土壤中Se等有益元素含量总体较高,其中Se含量达到富硒土地标准的表层土壤点位占全部样品点位的76%;表层土壤中Cd含量超标的点位占48%,其他有害元素仅个别点位超标,Cd是制约该地区富硒土地资源开发的主要不利因素。在研究区圈定了61.4 km2的富硒土地资源,认为研究区东部土壤富硒的物质来源是二叠系灰岩,可以利用当地灰岩提升富硒土地资源品质,降低生态风险。  相似文献   

多期构造变形事件对吉林南部大横路Cu- Co矿床富集成矿的制约     

田忠华  刘福来  刘超辉  朱志勇  王慧宁 《地质学报》2023,97(11):3673-3695

钴矿是重要的战略性金属矿产资源之一,对其成矿作用(如构造与成矿的关系)进行深入的研究能为前期指导找矿提供理论依据。本文对中国东部吉林白山市三道沟镇三岔河村大横路Cu-Co矿开展了相关工作,包括野外构造解析、钻孔-岩芯资料分析、钻孔薄片综合矿物分析系统(TIMA)实验和区域相关岩石年代学等。构造解析显示大横路Cu-Co矿围岩变形包括层片交切、S₁面理和褶劈理等构造要素。钻孔-岩芯资料分析矿区发育大量F₂紧闭褶皱、逆冲断层及断层相关褶皱、倒转褶皱F₂等。钻孔、探槽薄片样品TIMA实验显示含Co流体大量富集于低角度逆冲断裂、倒转褶皱韧性剪切域和断层相关褶皱转折端处。这些工作显示走向为NE的低角度逆冲断裂及断层相关褶皱对大横路Cu-Co矿的富集起到关键的控制作用。相关年代学工作,结合前人研究及大量区域地质资料表明:(1)矿区内逆冲断层及褶皱等控矿构造要素为古元古代构造事件的产物;(2)中生代构造事件对成矿作用的制约(Cu-Co矿的再富集)可能来自于白垩纪大规模的伸展作用。  相似文献   

建筑变形测量成果质量检验问题分析     

杨绪峰  彭凯笛  陈宇恒 《测绘与空间地理信息》2021,44(1):210-212

近几年,全国开展了多次变形测量成果质量检验工作且效果显著。本文首先简要介绍了全国建筑变形测量成果质量检验工作相关内容,其次结合全国33个建筑变形测量成果受检项目中出现的较严重的质量问题,从成果类型、质量元素、典型问题3个方面对成果质量情况进行分析,最后根据分析结论与检验情况为建筑变形测量成果在生产中的质量控制及质量检验提供建议。  相似文献