scholarly journals Study on Spatial-temporal Variation of Atmospheric Pollution in China between 2014 and 2019

2019 ◽  
Author(s):  
Guo Peng ◽  
Umarova Aminat Batalbievna ◽  
Luan Yunqi
Keyword(s):  
Spatial Variation ◽  
Temporal Variation ◽  
Atmospheric Pollution ◽  
Inner Mongolia ◽  
Mass Concentration ◽  
Environmental Governance ◽  
Mainland China ◽  
Temporal Distribution ◽  
Temporal Variations ◽  
Atmospheric Environment

AbstractThe study in this paper reveals that the atmospheric contaminants in mainland China is of concentricity in spatial distribution, persistence in temporal distribution and correlation between different parameters. This spatial-temporal variation law plays an important role in improving and addressing the problem with atmospheric environment of given cities and regions by employing focused and pointed measures. In this paper, seven kinds of atmospheric pollution parameters including PM2.5, PM10, AQI, CO, NO2, O3 and SO2 in 370 Chinese cities from 2014 to 2019 are analyzed based on their hourly mass concentration. The spatial-temporal variations of each parameter in each separated year are obtained by using interpolation calculation towards the annual atmospheric pollution parameters. The results show that higher mass concentration (including the highest mass concentration) of PM2.5, AQI, PM10, CO, NO2, SO2 mainly concentrated in Beijing-Tianjin-Hebei region in the northeast of mainland China and its neighboring regions and Xinjiang region in the northwest of mainland China. The spatial variation of PM2.5, AQI, PM10, CO, NO2, SO2 experienced similar trend. Higher mass concentration (including the highest mass concentration) of O3 mainly concentrated in Qinghai and Inner Mongolia in the central north of mainland China and Shandong on the right side of Beijing-Tianjin-Hebei region. The spatial variation of O3 experienced different trend from that of other parameters. PM2.5, AQI, PM10 indicated increase and decrease, followed by increase and decrease again with time, which was a S-shaped change. Almost the same temporal variation happened to PM2.5, AQI, PM10 and to CO, NO2, SO2, which was opposite to O3. The analysis from the perspective of the annual highest mass concentration of PM2.5, AQI, PM10, NO2 and O3 indicates the atmospheric environment of mainland China had not been authentically improved by 2019. The analysis from the perspective of the annual highest mass concentration of CO and SO2 indicates the atmospheric environment of mainland China had been authentically improved by 2019. What should we do immediately is to strengthen environmental governance and address the source of contamination in Beijing-Tianjin-Hebei region in the northeast of China, Xinjiang region in the northwest of China, Qinghai and Inner Mongolia regions in the central north of China.

scholarly journals Spatial and Temporal Variation in Microbial Diversity and Community Structure in a Contaminated Mangrove Wetland

2020 ◽  
Vol 10 (17) ◽  
pp. 5850
Author(s):  
Jiaojiao Ma ◽  
Ting Zhou ◽  
Chunyu Xu ◽  
Dawen Shen ◽  
Songjun Xu ◽  
...  
Keyword(s):  
Community Structure ◽  
Spatial Variation ◽  
Temporal Variation ◽  
Bacterial Diversity ◽  
Diversity Index ◽  
Total Carbon ◽  
Spatial And Temporal Variation ◽  
Rrna Gene ◽  
Mangrove Wetland ◽  
Mangrove Soils

Field and laboratory investigations were conducted to characterize bacterial diversity and community structure in a badly contaminated mangrove wetland adjacent to the metropolitan area of a megacity in subtropical China. Next-generation sequencing technique was used for sequencing the V4–V5 region of the 16s rRNA gene on the Illumina system. Collectively, Proteobacteria, Chloroflexi, Planctomycetes, Actinobacteria and Bacteroidetes were the predominant phyla identified in the investigated soils. A significant spatial variation in bacterial diversity and community structure was observed for the investigated mangrove soils. Heavy metal pollution played a key role in reducing the bacterial diversity. The spatial variation in soil-borne heavy metals shaped the spatial variation in bacterial diversity and community structure in the study area. Other environmental factors such as total carbon and total nitrogen in the soils that are affected by seasonal change in temperature could also influence the bacterial abundance, diversity and community structure though the temporal variation was relatively weaker, as compared to spatial variation. The bacterial diversity index was lower in the investigated site than in the comparable reference site with less contaminated status. The community structure in mangrove soils at the current study site was, to a remarkable extent, different from those in the tropical mangrove wetlands around the world.

scholarly journals Human health impact assessment and temporal distribution of trace elements in Copșa Mică- Romania

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Katalin Bodor ◽  
Zsolt Bodor ◽  
Alexandru Szép ◽  
Róbert Szép
Keyword(s):  
Trace Elements ◽  
Hazard Quotient ◽  
Temporal Distribution ◽  
Health Impact ◽  
Temporal Variations ◽  
Carcinogenic Risk ◽  
Dermal Absorption ◽  
Safe Limit ◽  
Adults And Children ◽  
Mean Concentration

AbstractThe present study aims to analyze the temporal variations of PM10 and to assess the health risk indexes caused by trace elements from particulate matter (PM10) via inhalation, ingestion, and dermal absorption by adults and children in Copșa Mică (Romania) during 2009–2019. The results revealed a high multi-annual mean concentration of PM10 and trace elements. The analyzed air pollutants showed a decreasing trend during the studied years, therefore 44.11%, 43.48%, 36.07%, 16.02%, and 15.80% lower values were observed for As, Cd, Ni, PM10, and Pb, respectively, due to environmental regulations. The daily exceedance percentage of Pb and Cd was very high, representing 21.74% and 11.26%, followed by PM10 and As concentrations with 4.72% and 3.92%. The ratio between the trace element concentration measured in Copșa Mică and the country average was 2.46, 4.01, 2.44 and 10.52 times higher for As, Cd, Ni and Pb. The calculated Hazard Quotient values via inhalation were higher than the safe limit (1), which accounted 1.81, 3.89 and 4.52, for As, Cd and Ni, respectively, indicating that the trace elements might present a non-carcinogenic risk to both adults and children. Furthermore, the concentration of all studied trace elements in Copșa Mică showed cancer risk for adults via inhalation and dermal absorption as well.

scholarly journals Spatial distribution and temporal variation of microcrustaceans assembly (Cladocera and Copepoda) in different compartments of a reservoir in the brazilian semiarid region

2018 ◽  
Vol 30 (0) ◽  
Author(s):  
Josiane Souza Santos ◽  
Nadson Ressyé Simões ◽  
Sérgio Luiz Sonoda
Keyword(s):  
Spatial Distribution ◽  
Spatial Variation ◽  
Temporal Variation ◽  
Aquatic Macrophytes ◽  
Temporal Dynamics ◽  
Lateral Compartment ◽  
Spatial And Temporal Variation ◽  
Semiarid Region ◽  
Brazilian Semiarid ◽  
Significant Spatial Variation

Abstract Aim: The objective of this study was to investigate the spatial and temporal variation of microcrustacean assemblages of a reservoir in the Brazilian semiarid region. Methods Physical and chemical water variables and samples of microcrustaceans were collected at eight sites of the reservoir between July 2013 and November 2014, in a total of seven campaigns. For this study, the reservoir was categorized in two compartments: lateral and central. Results Limnological variables showed significant temporal variation (PERMANOVA, Pseudo-F = 19.51, p = 0.001). Higher turbidity values and suspended solids were observed in the rainiest months, while during the dry months, we measured higher values of transparency, dissolved oxygen, and chlorophyll-a. It was not found significant spatial variation of limnological variables (PERMANOVA, Pseudo-F = 0.96; p = 0.394). During the study period, ten species were recorded: four Cladocera (Ceriodaphnia cornuta, Daphnia gessneri, Diaphanosoma birgei and Diaphanosoma spinulosum ) three Copepoda Calanoida (Argyrodiaptomus azevedoi, Notodiaptomus cearensis and Notodiaptomus iheringi) and three Copepoda Cyclopoida (Macrocyclops albidus, Thermocyclops minutus and Thermocyclops decipiens). The microcrustacean assemblages showed significant temporal variation (PERMANOVA, Pseudo-F = 4.34; p = 0.001) as well as significant spatial variation (PERMANOVA, Pseudo-F = 9.46; p = 0.001). The highest values of abundance and richness were observed in the lateral compartment, this result is mainly related to the presence of aquatic macrophytes in this region, because the analysis of partial RDA indicated that limnological variables explained only 11% of this variation (Pseudo-F = 2.08, p = 0.001). Conclusions The results suggest that the seasonality of the semiarid is an important factor in the temporal dynamics of the limnological variables, while the aquatic macrophytes play an important role in the spatial distribution of the microcrustacean assembly.

scholarly journals Temporal and spatial variation of Myriapoda (Diplopoda and Chilopoda) assemblages in a Neotropical floodplain

2018 ◽  
Vol 18 (2) ◽  
Author(s):  
Lorhaine Santos-Silva ◽  
Tamaris Gimenez Pinheiro ◽  
Amazonas Chagas-Jr ◽  
Marinêz Isaac Marques ◽  
Leandro Dênis Battirola
Keyword(s):  
Spatial Variation ◽  
Habitat Type ◽  
Temporal Distribution ◽  
High Water ◽  
Trophic Levels ◽  
Temporal And Spatial Variation ◽  
Ecosystem Integrity ◽  
Mato Grosso ◽  
Temporal And Spatial ◽  
Hydrological Cycles

Abstract: Myriapods constitute important edaphic macrofauna taxa which dwell in different trophic levels and influence the dynamics of these environments. This study evaluated the variation in composition, richness and abundance of edaphic myriapod assemblages as a function of the distribution and structure of flooded and non-flooded habitats (spatial variation) and hydrological seasonality (temporal variation) in a floodplain of the northern Pantanal region of Mato Grosso, Brazil. Sampling was carried out in three areas of the Poconé Pantanal, along an altitudinal and inundation gradient consisting of inundated and non-inundated habitats and different vegetation formations. Three quadrats (10 x 10 m) were delimited within each habitat type, where sampling was performed using pitfall traps and mini-Winkler extractors during the dry, rising water, high water and receding water periods of two hydrological cycles within the Pantanal (2010/2011 and 2011/2012). A total of 549 millipedes were collected, consisting of 407 Diplopoda and 142 Chilopoda distributed in six orders, 12 families and 20 species. The assemblages composition varied throughout the seasonal periods, indicating that the rising water and dry periods differed from the high water and receding water periods. In addition to the variation between seasonal periods, myriapod richness and abundance also varied in relation to areas consisting of different vegetation formations. Thus, it can be concluded that the hydrological seasonality associated with the inundation gradient and different vegetation types were determinant in the heterogeneous spatial and temporal distribution of myriapod assemblages, validating that the conservation of these invertebrates in the Pantanal is directly linked to the preservation of vegetation, and consequently, ecosystem integrity.

Assessing The Quality of Water Depth Derived From Volunteered Geographic Information (VGI) For Flood Monitoring. A Case Study of Hurricane Harvey In Harris County, Texas

2021 ◽  
Author(s):  
Abdullatif Alyaqout ◽  
T. Edwin Chow ◽  
Alexander Savelyev
Keyword(s):  
Water Depth ◽  
Temporal Distribution ◽  
Volunteered Geographic Information ◽  
Temporal Variations ◽  
Geographic Information ◽  
Text Messages ◽  
Quality Of Water ◽  
Significant Difference ◽  
Flood Monitoring

Abstract The primary objectives of this study are to 1) assess the quality of each volunteered geographic information (VGI) data modality (text, pictures, and videos), and 2) evaluate the quality of multiple VGI data sources, especially the multimedia that include pictures and videos, against synthesized water depth (WD) derived from remote sensing (RS) and authoritative data (e.g. stream gauges and depth grids). The availability of VGI, such as social media and crowdsourced data, empowered the researchers to monitor and model floods in near-real-time by integrating multi-sourced data available. Nevertheless, the quality of VGI sources and its reliability for flood monitoring (e.g. WD) is not well understood and validated by empirical data. Moreover, existing literature focuses mostly on text messages but not the multimedia nature of VGI. Therefore, this study measures the differences in synthesized WD from VGI modalities in terms of (1) spatial and (2) temporal variations, (3) against WD derived from RS, and (4) against authoritative data including (a) stream gauges and (b) depth grids. The results of the study show that there are significant differences in terms of spatial and temporal distribution of VGI modalities. Regarding VGI and RS comparison, the results show that there is a significant difference in WD between VGI and RS. In terms of VGI and authoritative data comparison, the analysis revealed that there is no significant difference in WD between VGI and stream gauges, while there is a significant difference between the depth grids and VGI.

Spatial variation in CO2 efflux from the soil in a mature beech forest ecosystem.

2021 ◽  
Author(s):  
Yihan Cai ◽  
Takahiro Nishimura ◽  
Hideyuki Ida ◽  
Mitsuru Hirota
Keyword(s):  
Spatial Variation ◽  
Temporal Variation ◽  
Forest Ecosystem ◽  
Linear Regression Analysis ◽  
Basal Area ◽  
Beech Forest ◽  
Controlling Factors ◽  
Spatial And Temporal Variation ◽  
Canopy Openness ◽  
Co2 Efflux

<p> Soil respiration (Rs) is the second largest carbon flux between the atmosphere and terrestrial ecosystem. Because of the large proportion, even small change in Rs would considerably impact the global carbon cycle. Therefore, it is important to accurately estimate Rs by taking its spatial and temporal variation into consideration. While the temporal variation of Rs and its controlling factors have been well-described, large unexplainable part still has been remained in the spatial variation of Rs especially in the forest ecosystems with complex structures. The objective of this study is to fill the knowledge gap about spatial variation of Rs and its controlling factors in a typical mature beech forest in Japan. Hypotheses of this study were, 1) Rs would show large spatial variation in the mature beech forest, 2) the spatial variation of Rs was mainly influenced by soil water content (SWC) and soil temperature (ST), 3) the two key factors were determined by the forest structures. This study was conducted in a 1- ha permanent study plot in the mature beech forest with significant gap-mosaic structures. To examine these hypotheses, Rs, SWC, ST and parameters related to forest structure, i.e. sum of basal area, diameter at breast height, number of trees, number of species within a radius of 5 m from the Rs measurement points, and canopy openness were measured at 121 points in different season between 2012 to 2013. In this study, all the measurements of Rs were conducted by using alkali-absorption technique.</p><p> Coefficient of variation of Rs was between 25 - 28 % which was similar to that of SWC in all the measurements. The spatial variation of Rs was relatively higher in July, August and September than that in June and October. There was no significant relationship in the spatial variation between Rs and ST in all the measurements, meanwhile, Rs was well explained by SWC in measurements conducted in August, September and October. Multiple linear regression analysis indicated that canopy openness and sum of basal area showed significant positive and negative correlation with SWC, respectively. And canopy openness explained SWC much more than sum of basal area did. This result suggested that SWC, the key factor determined the spatial variation of Rs, cannot be only explained by stems distribution and their characteristics, but also canopy architecture in the forest ecosystem.</p>

scholarly journals Temporal and spatial variation on heavy metal concentrations in the oyster Ostrea equestris on the northern coast of Rio de Janeiro State, Brazil

2005 ◽  
Vol 65 (1) ◽  
pp. 67-76 ◽  
Author(s):  
A. G Ferreira ◽  
A. L. S. Machado ◽  
I. R. Zalmon
Keyword(s):  
Heavy Metal ◽  
Spatial Variation ◽  
Rio De Janeiro ◽  
Dry Weight ◽  
Temporal Variations ◽  
Average Concentration ◽  
Northern Coast ◽  
High Concentrations ◽  
Janeiro State ◽  
Ostrea Equestris

Heavy metal (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) concentrations were determined by ICP-AES in Ostrea equestris from three beaches (Barra do Furado, Buena, and Ponta do Retiro) on the northern coast of Rio de Janeiro State. The average concentration was 0.8 ± 0.18, 0.4 ± 0.21, 58 ± 25.6, 249 ± 52.3, 11 ± 1.31, 0.55 ± 0.16, 0.13 ± 0.11, and 1131 ± 321 µg.g-1 dry weight for Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn respectively. Significant spatial variation (p < 0.05) between the samples areas occurred for Cr, Pb, and Zn with higher values in Barra do Furado; and for Cu in Ponta do Retiro. Significant temporal variations (p < 0.05) were observed for all metals except Cu. Temporal variability may be related to changes in the inputs of metals associated with suspended particles. Concentrations were similar to those found in areas under low pollution impact, except for Zn, the high concentrations of which probably reflect the physiological characteristics of these organisms.

scholarly journals Spatial variation of plant species richness in a sand dune field of northeastern Inner Mongolia, China

2016 ◽  
Vol 8 (3) ◽  
pp. 434-442
Author(s):  
Jing Wu ◽  
Jianqiang Qian ◽  
Xianzhang Hou ◽  
Carlos A. Busso ◽  
Zhimin Liu ◽  
...  
Keyword(s):  
Species Richness ◽  
Spatial Variation ◽  
Plant Species ◽  
Inner Mongolia ◽  
Sand Dune ◽  
Plant Species Richness ◽  
Dune Field
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