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Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Temperature is an environmental factor closely related to human daily life. Global climate change has led to an increase in the frequency and intensity of extreme meteorological events and climate anomalies. The associated adverse health also attracted public attention. Recently, with the processes of climate change and urbanization, epidemiological evidence pointing to a temporal change of population susceptibility to heat and/or cold over time has emerged. This paper summarized the definition of adaptation and then reviewed the studies on temporal change in temperature-related health risks at home and abroad, exploring whether the adaptation to temperature confirmed among different . Next, the research progress of influencing factors of adaptation. Finally, the common analytical methods of adaptation were reviewed. We also put forward an outlook based on the limitations of current exploratory studies. Rational identification of adaptation to temperature is of important scientific significance for the evaluation and prediction of the health effect of future climate.

Objective To investigate temporal variation in the abundance of total Vibrio parahaemolyticus in shellfish farm in Qingdao. Methods The abundance of total V. parahaemolyticus in shellfish and farm environment was detected using the most probable number real-time polymerase chain reaction(MPN real-time PCR) method during June 2013 and May 2014, and the correlation between V. parahaemolyticus abundance and the season was analyzed. Results The lowest level of MPN in shellfish and seawater presented from January to March, increased slowly before June, then rapidly rised up and reached the highest level until Augest. After that, it deceased rapidly to the lowest level in January. The lowest level of MPN in sediment was in March and the highest level kept from May to December(18 067.5-24 000.0 MPN/g), then dropped rapidly in January, and reached the lowest level in March(88.0 MPN/g). Conclusion Compared with the traditional methods, MPN-PCR has better sensitivity in reflecting V. parahaemolyticus growing trend with the the season and tempreture change. The level of bactiera abundence in oyster and seawater can be accurately assessed, which might play a role of early warning. The rapid growth time of V. parahaemolyticus in seawater and oyster is from June to Augest, which should be taken notice in the process of handling and eating to avoid foodborn disease.

Jiangsu is a major agricultural province and grain producing area. The comprehensive accounting of the temporal dynamics and composition of carbon footprint of major crops could provide decision-making basis for environmental management and green development of the agricultural sector in Jiangsu province. In this paper, Life Cycle Assessment (LCA) was used to calculate the carbon emission intensity of rice, wheat, maize, soybean and rapeseed production processes in Jiangsu province during 1990-2019,and the temporal dynamics, composition and influencing factors of carbon footprints of these crops were analyzed. The results showed that the carbon footprint per unit yield of major crops in Jiangsu province decreased but the carbon footprint per unit area increased in recent 30 years. The carbon footprint per unit yield for different crops showed as rapeseed(1. 74 kg (CO2-eq) .kg-1)> rice(1. 36 kg (CO2-eq) .kg-1)> wheat(0. 99 kg (CO2-eq) .kg-1)> maize(0. 81 kg (CO2-eq) .kg-1)> soybean(0. 64 kg CO2-eq kg-1). For the composition of carbon footprint, CH4 emission (54. 43%) and chemical fertilizer input (20. 65%) were the two major sources for rice production, while chemical fertilizer input and soil N2O emission are the most important sources for wheat, maize, soybean and rapeseed production. Random forest analysis showed that the variation of seed, nitrogen fertilizer and agricultural machinery input were the main driving factors for the interannual change of carbon footprints for different crops. Therefore, it is necessary to take targeted emission reduction strategies for different crop production and adjust agricultural inputs and process management in order to promote the green and efficient development of agriculture. [ABSTRACT FROM AUTHOR]

The earthquake has caused huge losses to the lives and property of Chinese people. The spatiotemporal characteristics of earthquake hazard losses are different from earthquake activities in mainland China, but there are few studies focused on the spatiotemporal variation of earthquake losses. In this study, data on earthquake losses in mainland China from 1993 to 2017 were collected to analyze its spatiotemporal characteristics. 299 earthquake hazards have been recorded during this period, which caused 0. 74 million dead, 4. 73 million injured, and 1. 1 trillion RMB direct economic loss. Earthquake hazards were much more serious in the western part of mainland China than in the eastern part, with the hot points where earthquake hazards took place locating in Yunnan, Sichuan, and the west part of Xinjiang provinces. However, the hot point locations of earthquake hazard losses were different from that where they took place: the hot points of life losses, injured people and direct economic losses all located in Sichuan province. Earthquake hazards which cost more than 50 life losses were crucial to mainland China' s earthquake losses. These catastrophes struck Yunnan province the most and made Sichuan province suffer the severest losses. Earthquake of low magnitude but huge damage occurred across mainland China, but Yunnan province experienced the most. Moreover, these earthquake hazards mainly cost direct economic loss in the eastern part of China but cost more life and injure in the western part of China. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The simultaneous quantitative investigation of aerosol ground observation data and particle concentration data is important for a better understanding of the vertical distribution characteristics of air pollution and formulating reasonable air pollution control measures in Chang'an, Xi'an. CE-318 measurements from October 2018 to April 2021 were systematically analyzed to reveal the seasonal and yearly variations in atmospheric aerosols in Chang'an. Then, the relationship between AOD and particle concentration in different seasons and different pollution degrees was explored. The obtained results were as follows:① the seasonal variation in AOD in Chang'an was determined, whereby autumn (1.02)>winter (1.00)>summer (0.63)>spring (0.47). Distinct monthly and inter-annual differences in AOD were observed, showing that the annual average of AOD in 2019 was higher than that in 2020. ② Obvious seasonal and monthly differences in aerosol main control modes were observed; the dominant mode of aerosols gradually changed from coarse mode to fine mode from spring to winter. The seasonal variation in the main control mode of aerosols in 2019 was similar to that in the whole observation period. The seasonal aerosol Angstrom wavelength index (Angstrom) was evenly distributed in 2020, and aerosol particles existed in coarse mode form. Generally speaking, the aerosol type in Chang'an was mostly mixed aerosol throughout the whole observation period. ③ Significant seasonal variations in the relationship between AOD and Angstrom was shown, in which the air pollution in spring was dominated by coarse mode aerosol particles. The local pollution in summer was caused by coarse and fine mode aerosol particles, and the fine mode particles were dominant when the pollution was obvious. The characteristic distribution of Angstrom in autumn and winter was similar; in case of local pollution, the coarse mode aerosol particles were dominant, and in case of obvious pollution, the fine mode aerosol particles were dominant. ④ The monthly concentration variation trend of PM 2.5 and PM 10 in Chang'an consistent with the maximum and minimum values appeared in January and summer, respectively. Seasonal variation in the concentration of PM 2.5 and PM 10 was apparent, with the highest values in winter. ⑤ A positive correlation between AOD and particulate matter concentration in different seasons and pollution levels was obtained during the observation periods, but the correlation coefficient differed. The specific characteristics were as follows:the correlation between AOD and PM 2.5 concentration was greater than that with PM 10 concentration; the correlation between AOD and particle concentration in autumn and winter was greater than that in spring and summer; and the correlation between AOD and particulate matter concentration was greater in polluted weather. Particle concentration was the most important determinant of AOD change, followed by relative humidity, which was the meteorological factor with the highest interpretation rate of AOD change in Chang'an. This indicates that a higher correlation between AOD and particle concentration would benefit from a reasonable humidity correction of AOD.

As an important precursor of ozone, volatile organic compounds (VOCs) have attracted much attention. This study analyzed the temporal variation and composition of atmospheric VOCs in the coastal background of the Pearl River Delta, using real-time online monitoring data of VOCs obtained at the Yangmeikeng Ecological Environment Monitoring Station from August 2019 to July 2020. The major sources of VOCs were identified using a receptor model based on the PMF (positive matrix factorization) and HYSPLIT (hybrid single particle Lagrangian integrated trajectory) models. The results showed that the annual mean concentration of anthropogenic VOCs in the coastal background area of the Pearl River Delta was 9.30×10 -9 (volume fraction). There was obvious seasonal variation of VOCs in this area, with higher values in autumn and winter and lower values in summer. The coastal background area of the Pearl River Delta exhibited a different diurnal variation pattern to that of cities and other backgrounds. While the peak of VOCs concentration mainly occurred in the morning, from 10:00 to 11:00, concentration remained at a low level during the early morning and after 15:00. Ethylene, propylene, toluene, isopentane, isoprene, m / p -xylene, n -butane, and acetylene were the key species that affected the chemical composition of VOCs. The air masses affecting the coastal background area of the Pearl River Delta were mainly short-distance air masses from elsewhere in the province (25%), ocean air masses (27%), coastal air masses (31%), and inland air masses outside the province (17%). Among them, the average concentration of VOCs was lowest under the influence of ocean air masses, which is mainly affected by the mixed source of ship emissions and aging VOCs, gasoline volatilization, and vehicle emissions. In comparison, the concentration level of VOCs increased by 70.1% to 148.8% under the influence of other air masses. The transmission effects of industrial sources, LNG and LPG volatiles, and petrochemical sources were more prominent. Generally, the atmosphere of coastal background areas was severely affected by anthropogenic pollution, especially by air pollution masses transported from the land, while the impact of pollution by ships near shore and tourist traffic cannot be ignored.

The light absorption of organic components in PM 2.5 was investigated at a suburban site in northern Nanjing from September 2018 to September 2019, and PM 2.5 compositional data and principal component analysis (PCA) were used to identify the sources of light-absorbing organic carbon (brown carbon, BrC). The results showed that the average light absorption coefficients of water-soluble organic carbon (WSOC) and methanol extractable organic carbon (MEOC) were (3.22±2.18) Mm -1 (Abs 365,w ) and (7.69±4.93) Mm -1 (Abs 365,m ), respectively. Significant correlations were observed between Abs 365,w and mass concentrations of WSOC ( r =0.72, P <0.01) and between Abs 365,m and mass concentrations of MEOC ( r =0.62, P =0.04). Both Abs 365,w and Abs 365,m exhibited seasonal variations, with higher values during winter than during summer,and higher diel variations at night than during the day. This can be attributed to meteorological characteristics during the winter and nighttime, i.e., decreased boundary layer height and increased atmospheric stability, enhanced primary emissions in winter,and stronger photobleaching effects during the summer and during the day. The annual average Abs 365,m /Abs 365,w ratio (2.60±0.92) was much larger than the average mass ratio of MEOC/WSOC (1.37±0.30), indicating that the water-insoluble fraction of MEOC had a stronger light absorption effect and dominated BrC absorption. No strong correlation ( r <0.60) was observed between WSOC, MEOC, Abs 365,m , and mass concentrations of K + , indication that biomass burning was not the main source of BrC in the study location. The mass absorption efficiency of WSOC (MAE 365,w ) and MEOC (MAE 365,m ) and their ratios (MAE 365,m /MAE 365,w ) showed similar seasonal variations to Abs 365 . The average MAE 365 value of the water-insoluble fraction of MEOC (4.10±5.15) m 2 ·g -1 was 6.0 and 2.9 times higher than that of MAE 365,w and MAE 365,m , respectively, suggested that BrC absorption was primarily attributable to water-insoluble components. In comparison to the absorption Ångström exponent of WSOC ( Å WSOC ), Å MEOC displayed marked temporal variability, which might be related to the seasonal variation in the emission of water-insoluble chromophores. According to the PCA results, the light absorption of PM 2.5 organic was mainly attributed to secondary formation and anthropogenic primary emissions rather than biomass burning.

As important precursors of near-surface ozone, secondary organic aerosols (SOAs), and volatile organic compounds (VOCs) play an important role in photochemical reactions and fine particle formation. In this study, real-time VOCs were measured continuously by Syntech Spectras GC955 analyzers at the regional background site of the North China Plain from September 1 to 27, 2017. The VOC concentration levels, compositions, spatiotemporal variations, and the ozone formation potential during the observation period were investigated. The potential sources of initial VOCs indicated from the diagnostic ratios were further studied. The averaged total mixing ratio of VOCs was 12.53×10 -9 . Among all measured VOC species, alkanes were the most abundant species, which accounted for 65.3% of the total concentrations, followed by alkenes (26.7%) and aromatics (6.5%). In addition, the total OH radical loss rate of VOCs ( L ·OH ) was 5.2 s -1 . In particular, the contribution of C4-C5 alkenes to L ·OH was as high as 61%, followed by C2-C3 alkenes, with a 12.8% contribution of L ·OH . The average ozone formation potential of VOCs was 36.5×10 -9 . Among all the measured VOC species, alkenes were the most abundant species, which accounted for 71.2%. Among alkenes, the contribution of C4-C5 alkenes was the most prominent. Although the concentration of alkanes in Shangdianzi was much higher than other VOC species, the ozone formation potential was lower. Diagnostic ratios and source implications suggested that Shangdianzi was affected mainly by biomass/biofuel/coal burning, with substantially elevated benzene levels during the observation period, whereas a slight influence of traffic-related emissions was observed.

In order to identify methane (CH 4 ) diffusion emissions characteristics and their impact factors in an eutrophic lake, CH 4 flux across the lake-air interface was observed in Meiliang Bay and the central zone of Lake Taihu over one year. The relationships between CH 4 flux and environmental factors and water quality indices were analyzed. The results indicated that the annual mean CH 4 diffusion flux in the eutrophic zone was significantly higher than that in the central zone, which were 0.140 mmol·(m 2 ·d) -1 and 0.024 mmol·(m 2 ·d) -1 , respectively. Additionally, the highest CH 4 flux appeared in the eutrophic littoral zone. The CH 4 flux varied seasonally, which was consistent with water temperature that peaked in summer. Furthermore, the difference in CH 4 flux between seasons was an order of magnitude. The temporal variation in CH 4 flux was mostly driven by wind speed and water temperature. The spatial correlation between CH 4 flux and dissolved organic carbon concentration was highly significant ( R 2 =0.62, P <0.01). Observing temporal and spatial patterns of CH 4 flux was necessary to accurately estimate whole-lake CH 4 emissions due to large variability across time and space.

In 2015, continuous volatile organic compound (VOC) monitoring was conducted for Dongsi (urban site), the southeast boundary site Yongledian, and Dingling (background site). The average annual mole fraction of atmospheric VOCs in urban areas was(48.93±31.03)×10 -9 , the average annual mole fraction of the southeast boundary was (54.55±39.64)×10 -9 , and the average annual mole fraction for the background site was(28.25±21.26)×10 -9 . Considering VOC components, alkanes occupy the highest proportion, followed by oxygen-containing VOCs, olefins, aromatic hydrocarbons, halogenated hydrocarbons, and acetylene. VOC concentration was higher in winter, lower in summer, higher at night and lower in the daytime. The concentration of acetylene in urban areas was higher in spring, summer and autumn, but higher in winter at the southeast boundary site. However, in the background, a small amount of direct anthropogenic interference was detectable, with the concentration of oxygen VOCs higher at noon and in summer. The species with high mole fractions in the VOCs were identified as mainly ethane, acetylene, ethylene, acetaldehyde, propane, acetone, n-butane, dichloromethane, and other low-carbon substances. The concentrations of benzene and toluene in the high-carbon group was relatively high. From the toluene/benzene ratio, it was found that Beijing VOCs were influenced by many sources other than transportation. However, the ratio of ethane/acetylene has been found to be significantly dependent on the aging of air mass in Beijing, with the southeast boundary particularly affected by movement of the aging air mass. Changes in the ratio of isopentane/TVOC showed that high summer temperature enhanced gasoline volatilization. The southeastern boundary point of OFP was the highest, followed by the urban area, with Dingling lower. The species with greater contribution to OFP were ethylene, propylene, acetaldehyde, paraxylene and toluene, with the higher mole fraction of alkanes making little contribution to OFP.