安徽省冬季PM2.5污染来源及其成因分析

随着中国城市化和工业化的加速发展，大气污染的问题日益突出，严重危害公众身体健康。基于安徽省逐小时PM2.5浓度监测数据，采用后向轨迹模式、潜在源因子分析法（PSCF）和权重浓度分析法（CWT），构建PM2.5来源分析模型，分析了安徽省PM2.5的来源，并结合地理探测器辨析了影响PM2.5本底贡献浓度的驱动因子。结果表明：（1）本底贡献、本底外溢和外地输送这3个动态过程对安徽省PM2.5浓度的时空变化有重要的影响；（2）PM2.5月累计逐小时测量浓度、总浓度、外地输送浓度、本底贡献浓度、本底外溢浓度和月均PM2.5本底排放贡献率，均在整体呈现出西南高、东北低的分布趋势，但前3项在安徽西北部的阜阳、亳州和淮北等地出现高值区；（3）安徽省约97.5%的面积外地输送贡献率>50%，下辖市PM2.5本底排放贡献率在30%~50%，说明1月污染以外地输送为主；（4）工厂密度、车辆保有量密度和人口密度对PM2.5月累计本底贡献浓度的解释力q值分别为0.33、0.47和0.61，通过与PM2.5月累计测量浓度地理探测分析结果的比较，表明人为要素与PM2.5月累计本底贡献浓度的关系更加密切。研究结果可为区域大气污染治理提供科学的参考依据。     

岸线码头密度对河道水动力和污染物输移影响分析——以武汉河段为例

为研究岸线码头密度对河流水动力变化及污染物输移的影响,以武汉河段为例,基于Mike21模型建立了适用于该河段的平面二维水动力-水质模型,计算了长为9.6 km的岸线范围内布置不同密度码头群后引起的附近区域内水位、流速变化以及突发水污染事故后的自净能力变化,从空间差异性、最大变幅等角度对比了三者的差异,并归纳了码头密度与水动力条件、污染物浓度变幅之间的关系.结果 表明:(1)随着码头密度增加,工程区上游水位变化较流速更敏感,工程区及下游局部位置水位变幅较小,而流速变化较为敏感,表现为前沿主流区流速增大,近岸区流速减小;当码头密度大于1.25～2.5座/km的临界范围后,水动力条件随码头密度的变幅逐渐减缓.(2)修建码头后,受水动力变化影响,工程区河段上游污染物浓度变化呈"峰前减、峰后增",但工程区下游呈"峰前增、峰后减"的特征;工程区间内表现为主流区浓度增大、近岸带浓度减小、高浓度滞留时间总体增加的变化特点.(3)受码头工程群影响,无论是区间整体上,还是局部范围内,污染物浓度相对水动力条件变幅更大,对河段内水源地的取水可能造成不利影响.以上认识对于河流岸线开发利用规模选取和效应评估具有参考意义.     

Landslide probability mapping by considering fuzzy numerical risk factor (FNRF) and landscape change for road corridor of Uttarakhand,India

Landslide poses severe threats to the natural landscape of the Lesser Himalayas and the lives and economy of the communities residing in that mountainous topography. This study aims to investigate whether the landscape change has any impact on landslide occurrences in the Kalsi-Chakrata road corridor by detailed investigation through correlation of the landslide susceptibility zones and the landscape change, and finally to demarcate the hotspot villages where influence of landscape on landslide occurrence may be more in future. The rational of this work is to delineate the areas with higher landslide susceptibility using the ensemble model of GIS-based multi-criteria decision making through fuzzy landslide numerical risk factor model along the Kalsi-Chakrata road corridor of Uttarakhand where no previous detailed investigation was carried out applying any contemporary statistical techniques. The approach includes the correlation of the landslide conditioning factors in the study area with the changes in land use and land cover (LULC) over the past decade to understand whether frequent landslides have any link with the physical and hydro-meteorological or, infrastructure, and socioeconomic activities. It was performed through LULC change detection and landslide susceptibility mapping (LSM), and spatial overlay analysis to establish statistical correlation between the said parameters. The LULC change detection was performed using the object-oriented classification of satellite images acquired in 2010 and 2019. The inventory of the past landslides was formed by visual interpretation of high-resolution satellite images supported by an intensive field survey of each landslide area. To assess the landslide susceptibility zones for 2010 and 2019 scenarios, the geo-environmental or conditioning factors such as slope, rainfall, lithology, normalized differential vegetation index (NDVI), proximity to road and land use and land cover (LULC) were considered, and the fuzzy LNRF technique was applied. The results indicated that the LULC in the study area was primarily transformed from forest cover and sparse vegetation to open areas and arable land, which is increased by 6.7% in a decade. The increase in built-up areas and agricultural land by 2.3% indicates increasing human interference that is continuously transforming the natural landscape. The landslide susceptibility map of 2019 shows that about 25% of the total area falls under high and very high susceptibility classes. The result shows that 80% of the high landslide susceptible class is contained by LULC classes of open areas, scrubland, and sparse vegetation, which point out the profound impact of landscape change that aggravate landslide occurrence in that area. The result acclaims that specific LULC classes, such as open areas, barren-rocky lands, are more prone to landslides in this Lesser Himalayan road corridor, and the LULC-LSM correlation can be instrumental for landslide probability assessment concerning the changing landscape. The fuzzy LNRF model applied has 89.6% prediction accuracy at 95% confidence level which is highly satisfactory. The present study of the connection of LULC change with the landslide probability and identification of the most fragile landscape at the village level has been instrumental in delineation of landslide susceptible areas, and such studies may help the decision-makers adopt appropriate mitigation measures in those villages where the landscape changes have mainly resulted in increased landslide occurrences and formulate strategic plans to promote ecologically sustainable development of the mountainous communities in India's Lesser Himalayas.

     

Health impacts of air pollution in China

•Impacts of air pollution on various body systems health in China were highlighted. •China’s actions to control air pollution and their effects were briefly introduced. •Challenges and perspectives of the health effects of air pollution are provided. The health effects of air pollution have attracted considerable attention in China. In this review, the status of air pollution in China is briefly presented. The impacts of air pollution on the health of the respiratory system, the circulatory system, the nervous system, the digestive system, the urinary system, pregnancy and life expectancy are highlighted. Additionally, China’s actions to control air pollution and their effects are briefly introduced. Finally, the challenges and perspectives of the health effects of air pollution are provided. We believe that this review will provide a promising perspective on the health impacts of air pollution in China, and further elicit more attention from governments and researchers worldwide.     

Winter arsenic pollution in 10 forest ecosystems in the mountainous border regions of the Czech Republic

Environmental Science and Pollution Research - Arsenic (As) concentrations and deposition fluxes were measured in snow and rime at 10 mountain-top sites near the borders between the Czech Republic...     

The land carrying capacity and environmental risk assessment of livestock and poultry breeding considering crop planting

Environmental Science and Pollution Research - At present, the contradiction between survival and ecology necessitates the integration of crop planting, chemical fertilizer application, and...     

Optimization of the O3/H2O2 process with response surface methodology for pretreatment of mother liquor of gas field wastewater

• Real ML-GFW with high salinity and high organics was degraded by O₃/H₂O₂ process. • Successful optimization of operation conditions was attained using RSM based on CCD. • Single-factor experiments in advance ensured optimal experimental conditions. • The satisfactory removal efficiency of TOC was achieved in spite of high salinity. • The initial pH plays the most significant role in the degradation of ML-GFW. The present study reports the use of the O₃/H₂O₂ process in the pretreatment of the mother liquor of gas field wastewater (ML-GFW), obtained from the multi-effect distillation treatment of the gas field wastewater. The range of optimal operation conditions was obtained by single-factor experiments. Response surface methodology (RSM) based on the central composite design (CCD) was used for the optimization procedure. A regression model with Total organic carbon (TOC) removal efficiency as the response value was established (R² = 0.9865). The three key factors were arranged according to their significance as: pH>H₂O₂ dosage>ozone flow rate. The model predicted that the best operation conditions could be obtained at a pH of 10.9, an ozone flow rate of 0.8 L/min, and H₂O₂ dosage of 6.2 mL. The dosing ratio of ozone was calculated to be 9.84 mg O₃/mg TOC. The maximum removal efficiency predicted was 75.9%, while the measured value was 72.3%. The relative deviation was found to be in an acceptable range. The ozone utilization and free radical quenching experiments showed that the addition of H₂O₂ promoted the decomposition of ozone to produce hydroxyl radicals (·OH). This also improved the ozone utilization efficiency. Gas chromatography-mass spectrometry (GC-MS) analysis showed that most of the organic matters in ML-GFW were degraded, while some residuals needed further treatment. This study provided the data and the necessary technical supports for further research on the treatment of ML-GFW.     

Triphenyl methyl phosphonium tosylate as an efficient phase transfer catalyst for ultrasound-assisted oxidative desulfurization of liquid fuel

Environmental Science and Pollution Research - The novel phosphonium-based ionic liquid (IL), triphenyl methyl phosphonium tosylate ([TPMP][Tos]), has been synthesized and applied as a phase...     

Effectiveness of autoencoder for lake area extraction from high-resolution RGB imagery: an experimental study

Environmental Science and Pollution Research - The surface areas of lakes alter constantly due to many factors such as climate change, land use policies, and human interventions, and their surface...