scholarly journals Centennial Records of PAHs and Black Carbon in Altay Mountain Peatlands, Xinjiang, China

2021 ◽  
Author(s):  
Nana Luo ◽  
Kunshan Bao ◽  
Bolong Wen ◽  
Rui Yu ◽  
Yelebolat Tuoliuhan ◽  
...  
Keyword(s):  
Black Carbon ◽  
Environmental Changes ◽  
Anthropogenic Impacts ◽  
Biomass Combustion ◽  
Past Century ◽  
Combustion Source ◽  
Emission Pattern ◽  
Peat Core ◽  
Polycyclic Aromatic ◽  
The Impact

Abstract Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are often used to indicate anthropogenic impacts on natural environmental changes during the past century. In this study, a 30 cm peat core was collected from the Jiadengyu (JDY) peatland in Altay Mountain and dated by the 137Cs and 210Pb methods. The total organic carbon, BC and PAHs contents in JDY peat core were 17.09-47.16%, 1.14-67.14 mg g-1 and 260.58-950.98 ng·g-1, respectively. The δ13CBC ranged from -31.5‰ to -27.43‰, with an average of -30.52‰. Scanning electron microscope (SEM) showed that the BC particles in the peat were lumpy or irregular in shape and retained the structure of plant fiber. The PAHs ratios, δ13CBC and the SEM result indicated the dominant biomass combustion source of BC in the peatland. The BC content increased from 1950 to 1980 and decreased after 1980. The change of BC and δ13CBC is different from the national BC emission pattern, probably reflecting the impact of local agricultural exploration and thus crop burning increase.

scholarly journals Centennial records of PAHs and black carbon in Altay mountain peatlands, Xinjiang, China

2021 ◽  
Author(s):  
Nana Luo ◽  
Kunshan Bao ◽  
Rui Yu ◽  
Xingtu Liu ◽  
Yelebolat Tuoliuhan ◽  
...  
Keyword(s):  
Black Carbon ◽  
Human Activities ◽  
Fossil Fuels ◽  
Biomass Combustion ◽  
Energy Structure ◽  
Past Century ◽  
Peat Core ◽  
Total Pahs ◽  
Polycyclic Aromatic ◽  
Regional Population

<p>Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are potentially proxies of changes in natural and human activities during the past century. It is important to identify historical BC sources and differentiate human activities contribution to BC in the environment. In this study, a 30 cm peat profile from the Jiadengyu (JDY) peatland in Altay Mountain was dated by the <sup>137</sup>Cs and <sup>210</sup>Pb methods. BC, total PAHs content and δ<sup>13</sup>C<sub>BC</sub> in JDY peat were tested. The results showed that the TOC, BC and PAHS contents in JDY peat core were 17.09 ~ 47.16%, 1.14 ~ 67.138 mg/g and 260.58 ~ 950.98 ng/g, respectively. The value of δ<sup>13</sup>C<sub>BC</sub> ranged -31.5‰ ~ -27.43‰, with an average of -30.52‰. The range of total PAHs concentrations in JDY peat core were between 260.59 ng/g and 950.98 ng/g. The BC was significantly correlated with PAHs and regional population. The BC fluxes have slightly increased since 1900s with the increasing population and cultivate area, and more significantly in 1980s.<strong> </strong>The burning of biomass and yak dung, fossil fuels, and human activities (mining, coking coal) may have important effects on the BC emission of soil in the Altay region. The change of BC and δ<sup>13</sup>C<sub>BC</sub> reflected the change of local energy structure. With the regional reclamation increasing and environment- friendly industry developing, the BC source of JDY peatland is mainly the result of the interaction between biomass combustion and fossil fuel combustion.</p>

scholarly journals Effects of Different Water Seasons on the Residual Characteristics and Ecological Risk of Polycyclic Aromatic Hydrocarbons in Sediments from Changdang Lake, China

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Javid Hussain ◽  
Zhenhua Zhao ◽  
Yong Pang ◽  
Liling Xia ◽  
Ittehad Hussain ◽  
...  
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
Temporal Distribution ◽  
Impact Factors ◽  
Source Characterization ◽  
Wet Season ◽  
Combustion Source ◽  
Study Results ◽  
Polycyclic Aromatic ◽  
The Impact

The sediments’ samples were collected from Changdang Lake for the concentration of fourteen polycyclic aromatic hydrocarbons in March (dry season), June (wet season), and September (temperate season) 2013. The highest average value of∑PAHswas detected as 295.28 ng/g dw in March, followed by 240.91 ng/g dw in June and 165.81 ng/g dw in September. Source characterization studies based on the analysis of diagnostic ratio (triangular plot method) suggested that the PAHs in sediments from Changdang Lake were mainly from the mixed combustion source of biomass and petroleum, and the origins of PAHs in different sampling sites have a great deal of temporal and spatial variability during different water seasons. Redundancy analysis was applied to identify the impact factors and the possible relationship between PAHs and environmental parameters. The predicted results showed that the main factors impacting PAHs temporal distribution were temperature, dissolved oxygen, pH, and oxidation-reduction potential, while conductivity showed secondary impacts on the PAHs distribution. Risk assessment of PAHs in sediments was carried out based on the US Sediments Quality Guidelines (SQGs). By comparing the present study results with SQGs standard values results showed that the adverse effects are not expected at the present levels of PAHs contamination observed in the sediments from Changdang Lake.

Decadal high-resolution multi-proxy analysis to reconstruct natural and human-induced environmental changes over the last 1350 cal. yr BP in the Altai Tavan Bogd National Park, western Mongolia

The Holocene ◽  
2020 ◽  
Vol 30 (7) ◽  
pp. 1016-1028 ◽  
Author(s):  
Julia Unkelbach ◽  
Kaoru Kashima ◽  
Gaadan Punsalpaamuu ◽  
Lyudmila Shumilovskikh ◽  
Hermann Behling
Keyword(s):  
High Resolution ◽  
Water Availability ◽  
National Park ◽  
Environmental Changes ◽  
Anthropogenic Impacts ◽  
Climatic Conditions ◽  
Forest Steppe ◽  
Permafrost Degradation ◽  
Rainfall Events ◽  
The Impact

The ‘Altai Tavan Bogd’ National Park in the north-western part of the Mongolian Altai, Central Asia, is located in a forest-steppe ecosystem. It occurs under the influence of extreme continental and montane climate and is sensitive to natural and anthropogenic impacts. High-resolution (<20 years per sample) multi-proxy data of pollen, non-pollen palynomorphs (NPPs), macro-charcoal, diatoms, and XRF scanning from radiocarbon-dated lacustrine sediments reveal various environmental changes and the impact of different settlement periods for the late-Holocene. From 1350 to 820 cal. yr BP (AD 600–1130), the distribution of grass steppe indicates a climate similar to present-day conditions. Rapid improvements of climatic conditions (e.g. increased rainfall events) possibly favored a recovery of forest-steppe encouraging nomadic movements into alpine areas. In the period from 820 to 400 cal. yr BP (AD 1130–1550), the decline of forested areas suggests an increasingly drier and possibly colder climate. Some political shifts during the Mongol Empire (744–582 cal. yr BP; AD 1206–1368) favored variations in nomadic grazing habits. After 400 cal. yr BP (AD 1550), moisture and temperature increased slightly, and from ca. 40 cal. yr BP (AD 1910) to present, annual temperature continued to increase more markedly favoring an additional water availability due to permafrost degradation. Diatom data suggest several intervals of increased water availability in all periods which might have caused erosion due to heavier rainfall events or increased snow melt. Immediately after most of these high-water intervals, NPP data reveal periods of increased grazing activities in the area.

scholarly journals Molluscan benthic communities at Brijuni Islands (northern Adriatic Sea) shaped by Holocene sea-level rise and recent human eutrophication and pollution

The Holocene ◽  
2018 ◽  
Vol 28 (11) ◽  
pp. 1801-1817 ◽  
Author(s):  
Sara-Maria Schnedl ◽  
Alexandra Haselmair ◽  
Ivo Gallmetzer ◽  
Anna-Katharina Mautner ◽  
Adam Tomašových ◽  
...  
Keyword(s):  
Sea Level ◽  
Adriatic Sea ◽  
Environmental Changes ◽  
Anthropogenic Impacts ◽  
Benthic Communities ◽  
Marine Species ◽  
Benthic Assemblages ◽  
Northern Adriatic Sea ◽  
Northern Adriatic ◽  
The Impact

The effects of and the interplay between natural and anthropogenic influences on the composition of benthic communities over long time spans are poorly understood. Based on a 160-cm-long sediment core collected at 44 m water depth in the NE Adriatic Sea (Brijuni Islands, Croatia), we document changes in molluscan communities since the Holocene transgression ~11,000 years ago and assess how they were shaped by environmental changes. We find that (1) a transgressive lag deposit with a mixture of terrestrial and marine species contains abundant seagrass-associated gastropods and epifaunal suspension-feeding bivalves, (2) the maximum-flooding phase captures the establishment of epifaunal bivalve-dominated biostromes in the photic zone, and (3) the highstand phase is characterized by increasing infaunal suspension feeders and declining seagrass-dwellers in bryozoan-molluscan muddy sands. Changes in the community composition between the transgressive and the highstand phase can be explained by rising sea level, reduced light penetration, and increase in turbidity, as documented by the gradual up-core shift from coarse molluscan skeletal gravel with seagrass-associated molluscs to bryozoan sandy muds. In the uppermost 20 cm (median age <200 years), however, epifaunal and grazing species decline and deposit-feeding and chemosymbiotic species increase in abundance. These changes concur with rising concentrations of nitrogen and organic pollutants due to the impact of eutrophication, pollution, and trawling in the 20th century. The late highstand benthic assemblages with abundant bryozoans, high molluscan diversity, and abundance of soft-bottom epi- and infaunal filter feeders and herbivores represent the circalittoral baseline community largely unaffected by anthropogenic impacts.

scholarly journals Recent environmental changes in the Yunnan–Guizhou Plateau inferred from organic geochemical records from the sediments of Fuxian Lake

Elem Sci Anth ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Haibo He ◽  
Zaihua Liu ◽  
Dongli Li ◽  
Hongbo Zheng ◽  
Jianxin Zhao ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Anthropogenic Impacts ◽  
Anthropogenic Activities ◽  
Sediment Cores ◽  
High Amplitude ◽  
Average Chain Length ◽  
Past Century ◽  
The Past ◽  
The 1950S ◽  
Guizhou Plateau

During the past century, many lacustrine environments have changed substantially at the ecosystem level as a result of anthropogenic activities. In this study, the distributions of n-alkane homologues, carbon isotopes (δ13Corg), organic carbon, and the C/N atomic ratio in two sediment cores from Fuxian Lake (Yunnan, southwest China) are used to elucidate the anthropogenic impacts on this deep, oligotrophic, freshwater lake. The carbon preference index (CPI) of long-chain components, average chain length (ACL), proportion of aquatic macrophytes (Paq), and terrigenous/aquatic ratios (TAR) show different temporal patterns that reflect variations in biological production. Notably, the n-alkane homologues are shown to be more sensitive to environmental changes than δ13Corg and the C/N ratio. Prior to the 1950s, minor variations in the sedimentary geochemical record were likely caused by climate changes, and they represent a natural stage of lake evolution. The onset of cultural eutrophication in Fuxian Lake occurred in the 1950s, when the n-alkane proxies collectively exhibited high-amplitude fluctuations but overall decreasing trends that coincided with population growth and related increases in land-use pressure. In the 21st century, Fuxian Lake has become even more eutrophic in response to human activities, as indicated by sharp increases in C/N ratio, Paq, δ13Corg, ACL, CPI, and TAR. Our findings provide robust molecular sedimentary evidence confirming that the environmental evolution of lakes in the Yunnan–Guizhou Plateau over the past century was closely associated with enhanced anthropogenic activities.

scholarly journals Past environmental changes affected lemur population dynamics prior to human impact in Madagascar

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Helena Teixeira ◽  
Vincent Montade ◽  
Jordi Salmona ◽  
Julia Metzger ◽  
Laurent Bremond ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Human Impact ◽  
Environmental Changes ◽  
Anthropogenic Impacts ◽  
Population Decline ◽  
Primate Species ◽  
Population Fluctuations ◽  
Tropical Regions ◽  
The Past ◽  
The Impact

AbstractQuaternary climatic changes have been invoked as important drivers of species diversification worldwide. However, the impact of such changes on vegetation and animal population dynamics in tropical regions remains debated. To overcome this uncertainty, we integrated high-resolution paleoenvironmental reconstructions from a sedimentary record covering the past 25,000 years with demographic inferences of a forest-dwelling primate species (Microcebus arnholdi), in northern Madagascar. Result comparisons suggest that climate changes through the African Humid Period (15.2 – 5.5 kyr) strongly affected the demographic dynamics of M. arnholdi. We further inferred a population decline in the last millennium which was likely shaped by the combination of climatic and anthropogenic impacts. Our findings demonstrate that population fluctuations in Malagasy wildlife were substantial prior to a significant human impact. This provides a critical knowledge of climatically driven, environmental and ecological changes in the past, which is essential to better understand the dynamics and resilience of current biodiversity.

Designing a CRM Framework for online & offline sports footwear retailers

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Rodrigo Cueva ◽  
Guillem Rufian ◽  
Maria Gabriela Valdes
Keyword(s):  
Environmental Changes ◽  
Customer Relationship ◽  
Business Strategies ◽  
Economic Sectors ◽  
Running Shoes ◽  
Brick And Mortar ◽  
Key Factor ◽  
On Line ◽  
The Impact

The use of Customer Relationship Managers to foster customers loyalty has become one of the most common business strategies in the past years.  However, CRM solutions do not fill the abundance of happily ever-after relationships that business needs, and each client’s perception is different in the buying process.  Therefore, the experience must be precise, in order to extend the loyalty period of a customer as much as possible. One of the economic sectors in which CRM’s have improved this experience is retailing, where the personalized attention to the customer is a key factor.  However, brick and mortar experiences are not enough to be aware in how environmental changes could affect the industry trends in the long term.  A base unified theoretical framework must be taken into consideration, in order to develop an adaptable model for constructing or implementing CRMs into companies. Thanks to this approximation, the information is complemented, and the outcome will increment the quality in any Marketing/Sales initiative. The goal of this article is to explore the different factors grouped by three main domains within the impact of service quality, from a consumer’s perspective, in both on-line and off-line retailing sector.  Secondly, we plan to go a step further and extract base guidelines about previous analysis for designing CRM’s solutions focused on the loyalty of the customers for a specific retailing sector and its product: Sports Running Shoes.

scholarly journals Review on Sublethal Effects of Environmental Contaminants in Honey Bees (Apis mellifera), Knowledge Gaps and Future Perspectives

2021 ◽  
Vol 18 (4) ◽  
pp. 1863 ◽  
Author(s):  
Agata Di Noi ◽  
Silvia Casini ◽  
Tommaso Campani ◽  
Giampiero Cai ◽  
Ilaria Caliani
Keyword(s):  
Apis Mellifera ◽  
Honey Bees ◽  
Sublethal Effects ◽  
Integrated Approach ◽  
Anthropogenic Contamination ◽  
Knowledge Gaps ◽  
Pollination Services ◽  
General Decline ◽  
Polycyclic Aromatic ◽  
The Impact

Honey bees and the pollination services they provide are fundamental for agriculture and biodiversity. Agrochemical products and other classes of contaminants, such as trace elements and polycyclic aromatic hydrocarbons, contribute to the general decline of bees’ populations. For this reason, effects, and particularly sublethal effects of contaminants need to be investigated. We conducted a review of the existing literature regarding the type of effects evaluated in Apis mellifera, collecting information about regions, methodological approaches, the type of contaminants, and honey bees’ life stages. Europe and North America are the regions in which A. mellifera biological responses were mostly studied and the most investigated compounds are insecticides. A. mellifera was studied more in the laboratory than in field conditions. Through the observation of the different responses examined, we found that there were several knowledge gaps that should be addressed, particularly within enzymatic and molecular responses, such as those regarding the immune system and genotoxicity. The importance of developing an integrated approach that combines responses at different levels, from molecular to organism and population, needs to be highlighted in order to evaluate the impact of anthropogenic contamination on this pollinator species.

scholarly journals Grill Workers Exposure to Polycyclic Aromatic Hydrocarbons: Levels and Excretion Profiles of the Urinary Biomarkers

2020 ◽  
Vol 18 (1) ◽  
pp. 230
Author(s):  
Marta Oliveira ◽  
Sílvia Capelas ◽  
Cristina Delerue-Matos ◽  
Simone Morais
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
High Performance ◽  
Principal Component ◽  
Fold Increase ◽  
Urinary Biomarkers ◽  
Analysis Model ◽  
Exposed Workers ◽  
Polycyclic Aromatic ◽  
The Impact

Grilling activities release large amounts of hazardous pollutants, but information on restaurant grill workers’ exposure to polycyclic aromatic hydrocarbons (PAHs) is almost inexistent. This study assessed the impact of grilling emissions on total workers’ exposure to PAHs by evaluating the concentrations of six urinary biomarkers of exposure (OHPAHs): naphthalene, acenaphthene, fluorene, phenanthrene, pyrene, and benzo(a)pyrene. Individual levels and excretion profiles of urinary OHPAHs were determined during working and nonworking periods. Urinary OHPAHs were quantified by high-performance liquid-chromatography with fluorescence detection. Levels of total OHPAHs (∑OHPAHs) were significantly increased (about nine times; p ≤ 0.001) during working comparatively with nonworking days. Urinary 1-hydroxynaphthalene + 1-hydroxyacenapthene and 2-hydroxyfluorene presented the highest increments (ca. 23- and 6-fold increase, respectively), followed by 1-hydroxyphenanthrene (ca. 2.3 times) and 1-hydroxypyrene (ca. 1.8 times). Additionally, 1-hydroxypyrene levels were higher than the benchmark, 0.5 µmol/mol creatinine, in 5% of exposed workers. Moreover, 3-hydroxybenzo(a)pyrene, biomarker of exposure to carcinogenic PAHs, was detected in 13% of exposed workers. Individual excretion profiles showed a cumulative increase in ∑OHPAHs during consecutive working days. A principal component analysis model partially discriminated workers’ exposure during working and nonworking periods showing the impact of grilling activities. Urinary OHPAHs were increased in grill workers during working days.

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