Hai-Long Gao, Cen-Yao Shang, Xiao-Dong Pei, Hui-Fang Xie, Bing-Yu Wang
{"title":"[Phytic Acid Modification Enhanced Cadmium Sorption and Immobilization of Sludge-based Hydrochar].","authors":"Hai-Long Gao, Cen-Yao Shang, Xiao-Dong Pei, Hui-Fang Xie, Bing-Yu Wang","doi":"10.13227/j.hjkx.202309150","DOIUrl":"https://doi.org/10.13227/j.hjkx.202309150","url":null,"abstract":"<p><p>Phytic acid-assisted sludge hydrothermal carbonization was employed to synthesize phytic acid-modified hydrochar via a one-step method. The surface morphology, pore structure, elemental composition, functional groups, and thermal stability of the phytic acid-modified hydrochar were characterized. Sorption kinetics and isotherm experiments were conducted to investigate the effects of humic acid, temperature, and pH on the sorption process of cadmium (Cd) onto the phytic acid-modified hydrochar. The Cd fixation ability was evaluated through soil passivation experiments. The results demonstrated that the surface of the phytic acid-modified hydrochar exhibited an abundance of phosphoric acid groups, enhanced electronegativity, and thermal stability. Furthermore, both the sorption rate and maximum sorption capacity for Cd increased by 1.88 times and 1.22 times compared to that in unmodified hydrochar, respectively, owing to the presence of phosphoric acid groups that enhanced complexation and electrostatic interaction with Cd. Elevated temperatures, higher pH values, and coexistence with humic acids were beneficial for enhancing Cd sorption onto phytic acid-modified hydrochar. When heavy metals such as Cu, Zn, and Pb coexisted, the sorption capacity of phytic acid-modified hydrochar for Cd was 0.77-6.88 times higher than that for other metals. Phyic acid-modified hydrochar exhibited excellent efficiency in fixing Cd (56.1%-81.l%), mitigating the loss of available nutrients in soil and significantly increasing the AP content in the soil. In conclusion, the use of phytic acid-modified hydrochar could effectively remove Cd from water and serve as a promising soil amendment for stabilizing soil Cd content.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142018991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Evolution Characteristics of PM<sub>2.5</sub> and O<sub>3</sub> and Their Synergistic Effects on Atmospheric Compound Pollution in Tangshan].","authors":"Li-Hui Han, Tong Lan, Shui-Yuan Cheng, Ying-Ao Wang, Chao-Nan Qi, Jian Tian, Hai-Yan Wang, Deng-Yue Han, Shen-Ao Wang","doi":"10.13227/j.hjkx.202308122","DOIUrl":"https://doi.org/10.13227/j.hjkx.202308122","url":null,"abstract":"<p><p>The concentrations of atmospheric pollutants PM<sub>2.5</sub>, O<sub>3</sub>, SO<sub>2</sub>, NO<sub>2</sub>, and CO together with the meteorological factors of temperature (<i>T</i>), relative humidity (RH), wind speed, and other relevant data in Tangshan from 2015 to 2021 were collected to study the variation characteristics of PM<sub>2.5</sub> and O<sub>3</sub> at different periods in Tangshan City in the past seven years and their influencing factors, to discuss the contributions of air mass transport to PM<sub>2.5</sub> and O<sub>3</sub> pollution, and to reveal the synergistic influence mechanism of PM<sub>2.5</sub> and O<sub>3</sub> on atmospheric compound pollution by using correlation analysis and backward trajectory cluster analysis techniques. The results showed that PM<sub>2.5</sub> concentrations in Tangshan decreased year by year from 2015 to 2021, whereas O<sub>3</sub> concentration showed a unimodal trend, with the peak appearing in 2017. Both PM<sub>2.5</sub> and O<sub>3</sub> concentrations showed obvious seasonal variation trends; PM<sub>2.5</sub> was characterized by the highest concentration in winter and the lowest concentration in summer, whereas O<sub>3</sub> was characterized by the highest concentration in summer and the lowest concentration in winter. In addition, the diurnal variation in PM<sub>2.5</sub> showed a bimodal distribution, with the peak occurring during the morning and evening on weekdays, and O<sub>3</sub> showed a unimodal distribution, with the peak value appearing during the period with strong ultraviolet radiation in the afternoon. PM<sub>2.5</sub> had a significant positive correlation with SO<sub>2</sub>, NO<sub>2</sub>, and CO, whereas O<sub>3</sub> had a significant positive correlation with radiation and temperature. Under the different pollution conditions, PM<sub>2.5</sub> and O<sub>3</sub> were affected by air mass transports from different directions. Being impacted by various factors, the synergistic effect of PM<sub>2.5</sub> and O<sub>3</sub> on atmospheric compound pollution showed an obvious negative effect in winter, whereas there was an obvious positive effect in spring, summer, and autumn. Under the backgrounds of different pollutions, when the concentration of PM<sub>2.5</sub> exceeded 150 μg·m<sup>-3</sup>, the synergistic effect of PM<sub>2.5</sub> and O<sub>3</sub> showed an obvious negative effect.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142018966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cong An, Yuan-Yuan Ji, Wang-Hui Chu, Xiao-Yu Yan, Fang Bi, Rui Gao, Li-Kun Xue, Fan-Yi Shang, Ji-Dong Li, Hong Li
{"title":"[Spatiotemporal Distribution Characteristics of Ground-level-ozone and Its Relationship with Meteorological Conditions in a Representative City in the Bohai Rim from 2017 to 2022].","authors":"Cong An, Yuan-Yuan Ji, Wang-Hui Chu, Xiao-Yu Yan, Fang Bi, Rui Gao, Li-Kun Xue, Fan-Yi Shang, Ji-Dong Li, Hong Li","doi":"10.13227/j.hjkx.202308225","DOIUrl":"https://doi.org/10.13227/j.hjkx.202308225","url":null,"abstract":"<p><p>In recent years, ground-level-ozone(O<sub>3</sub>) pollution in urban areas in the Bohai Rim has attracted wide attention. Based on the analysis of the spatiotemporal distribution characteristics of O<sub>3</sub> concentration in Dongying, a representative city in the Bohai Rim from 2017 to 2022, the effects of meteorological factors and sea-land breeze circulation on O<sub>3</sub> concentration were evaluated. The results showed that: ① From 2017 to 2022, the annual assessment value of O<sub>3</sub> concentration in Dongying showed a fluctuating upward trend, and the pollution days with O<sub>3</sub> as the primary pollutant increased. O<sub>3</sub> pollution mainly occurred in spring, summer, and autumn, with the most severe O<sub>3</sub> pollution episodes typically occurring in May and June, and the duration of O<sub>3</sub> pollution season tended to be longer. The monthly variation in the daily maximum 8-h average ozone (MDA8 O<sub>3</sub>) presented a bimodal distribution, with significant increases in the 5th and 25th percentiles, and the spatial distribution was \"high in the north and south, low in the middle.\" In addition, the nocturnal O<sub>3</sub> concentration in recent years in Dongying also showed a significant increase trend. ② Meteorological factors greatly influenced O<sub>3</sub> concentration in Dongying. When the temperature was greater than 30℃, the relative humidity was less than 50%, and the wind direction was south-southwest or east-northeast, a high O<sub>3</sub> value was more likely to occur. Meteorological factors contributed 30% of the MDA8 O<sub>3</sub> variation in Dongying during the study period. In the case of moderate and severe O<sub>3</sub> pollution, the contribution of meteorological factors to the change in MDA8 O<sub>3</sub> could be as high as 40%. ③ To some extent, sea-land breeze contributed to the occurrence of MDA8 O<sub>3</sub> exceeding the secondary standard limit value of the National Ambient Air Quality Standard. In the afternoon, the hourly concentration of O<sub>3</sub> during the sea-land breeze days was approximately 20 μg·m<sup>-3</sup> higher than that during the non-sea-land breeze days. On the days of moderate and severe O<sub>3</sub> pollution, the O<sub>3</sub> concentration during the sea-land breeze days from 10:00 to 16:00 was higher than that during non-sea-land breeze days, and the O<sub>3</sub> concentration was also at a high level from 20:00 to 23:00 on sea-land breeze days. In the O<sub>3</sub> pollution season, the sea-land breeze could significantly affect the O<sub>3</sub> level in coastal cities, which could bring significant challenges for O<sub>3</sub> pollution prevention and control in this region. In the future, cities in the Bohai Rim need to further strengthen regional joint prevention and control of O<sub>3</sub> pollution and increase emission reduction efforts of nitrogen oxides and volatile organic compounds. This strategy could effectively lower pollutan","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142018996","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Meta-analysis of Heavy Metal Pollution in Soil-crop Systems in China's Urban-Rural Fringe].","authors":"Zong-Xu Bai, Li Yang, Hong-Lei Wang, Tao Chen","doi":"10.13227/j.hjkx.202309165","DOIUrl":"10.13227/j.hjkx.202309165","url":null,"abstract":"<p><p>Owing to the influence of human activities, the issue of heavy metal pollution in farmland soil at the urban-rural fringe has become increasingly prominent. An accurate understanding of the characteristics of soil-crop heavy metal pollution in these areas is of great significance for ensuring food safety and promoting social sustainable development. Most of the existing studies rely on small-scale field monitoring, but research at the national level has not effectively captured the unique pollution dynamics of this urban-rural interface. Based on the published literature, the present study investigated the status of heavy metal pollution in the soil-crop system within China's urban-rural fringe through Meta-analysis. On this basis, the study evaluated the risks to human health associated with heavy metals in major crops in a given region. The results showed that heavy metals were accumulated in farmland soil in the urban-rural fringe of China, especially in Cd (<i>I</i><sub>geo</sub> = 0.89) pollution, and its distinct spatial heterogeneity patterns emerged. When considering different types of cultivated land, paddy fields and irrigated land exhibited a higher tendency of heavy metal accumulation. From the varying urbanization levels, the accumulation of heavy metals in soils of small and medium-sized cities was more obvious. For crops in the urban-rural fringe, Cd and Pb had the highest exceedance rate in rice (28.25% and 39.64%) and wheat (27.72% and 42.72%). The health risk assessment results of heavy metals in crops showed that Cd was the main element that posed human health risks, which had some degree of non-carcinogenic risk and unacceptable carcinogenic risk to both children and adults.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142018987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Multi-time Scale Variation of Atmospheric Ammonia Concentration and Dry Deposition in a Paddy Rice Region in Subtropical China].","authors":"Hui-Xiu Zhan, Xiao Zhu, Juan Wang, Jian-Lin Shen, Yong Li, Jin-Shui Wu","doi":"10.13227/j.hjkx.202307243","DOIUrl":"https://doi.org/10.13227/j.hjkx.202307243","url":null,"abstract":"<p><p>Meteorological factors and anthropogenic activities significantly affect atmospheric ammonia (NH<sub>3</sub>) concentration and its dry deposition. Former studies have examined the spatial and temporal variability in atmospheric NH<sub>3</sub> concentrations at monthly scales. However, the characteristics of atmospheric concentrations at finer time scales such as hourly and daily scales and the influencing factors remain unclear. In this study, atmospheric NH<sub>3</sub> concentration and related meteorological factors were continuously monitored online for one year in a double cropping rice region in subtropical China, and atmospheric NH<sub>3</sub> concentration and its meteorological influencing factors as well as dry deposition were analyzed at different time scales (hourly, daily, and monthly). The main results were as follows: The annual average daily concentration of NH<sub>3</sub> in the rice area varied from 0.01 to 58.0 μg·m<sup>-3</sup> (in N, same below), and the annual average concentration was 5.3 μg·m<sup>-3</sup>. On the hourly scale, the 24-hour dynamics of atmospheric NH<sub>3</sub> concentration showed a unimodal pattern, and the time of the NH<sub>3</sub> peak appearance in different seasons was different; the time of the peak that appeared in winter lagged behind that in the other seasons. From the perspective of daily scale, NH<sub>3</sub> concentration was mainly affected by fertilization in the paddy fields, peaking at 1-3 days after fertilization and then gradually decreasing. On the monthly scale, NH<sub>3</sub> concentration peaked at 12.8 μg·m<sup>-3</sup> in July and was the lowest in October at 1.6 μg·m<sup>-3</sup>. On the hourly scale, NH<sub>3</sub> concentration varied seasonally due to the influences of meteorological factors, mainly as follows: NH<sub>3</sub> concentration showed significant positive correlations with air temperature and solar radiation in all four seasons and with wind speed in spring and summer, whereas it showed significant negative correlations with relative humidity except in winter. On the daily scale, NH<sub>3</sub> concentration showed a significant positive correlation with air temperature, rainfall, and solar radiation, whereas it showed a significant negative correlation with relative humidity. On the monthly scale, no significant correlation existed between each meteorological factor and NH<sub>3</sub> concentration. The annual dry deposition flux (in N) calculated from the hourly average NH<sub>3</sub> concentration was 8.5 kg·(hm<sup>2</sup>·a)<sup>-1</sup>, which was 11.6% higher than the annual flux calculated from the daily average and 12.4% higher than the annual flux calculated from the monthly average. In summary, there were significant daily and seasonal variations in atmospheric NH<sub>3</sub> concentration in the paddy rice region in subtropical China, and conducting hourly-scale observations of NH<sub>3</sub> concentration can help to reveal the multi-time scale va","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142018990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Spatio-temporal Pattern of Ecosystem Service Value Evolution in the Yihe River Basin in the Context of Land Use Change].","authors":"Shu-Yuan Yang, Zi-Jun Li","doi":"10.13227/j.hjkx.202307230","DOIUrl":"https://doi.org/10.13227/j.hjkx.202307230","url":null,"abstract":"<p><p>In this study, the modified equivalent factor method was applied to account for the long time series ecosystem service value (ESV) of the Yihe River Basin from 1975 to 2020 in the context of land use change, and the cold hot spot analysis and topographic position analysis methods were introduced to explore the characteristics of its spatial pattern. The results showed that: ① From 1975 to 2020, the land use type of the Yihe River Basin was dominated by arable land, and the land use changes were characterized by the rapid decrease of arable land and the continuous expansion of construction land, a slight increase in the area of forest land and grassland, a contraction of the water body area, and little change in the area of unused land. ② The modified equivalent factor method was more suitable for accounting for the ESV in the basin. From 1975 to 2020, the overall ESV of the basin showed an upward spiral trend (33.369-33.816 billion CNY), dominated by the regulating services. The ESV of arable land was the highest with a decreasing trend, whereas the ESV of unused land was the lowest. ③ In the horizontal spatial pattern, the hot spot of ESV was near mountains and reservoirs, and the cold spot of ESV was near urban areas. In terms of vertical spatial patterns, with growing topographic gradient, vertical changes in ESV for all land use types showed an increasing trend followed by a decreasing trend. The results of the study revealed the spatial and temporal patterns of ecosystem service values in the Yihe River Basin in the context of land use change and provide a scientific basis for optimizing the land use structure and spatial pattern and enhancing ecosystem services.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142018999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tian-Yi Sun, Jia-Chen Shen, Dian-Peng Li, Shu-Qing An, Xin Leng
{"title":"[Microplastic Characteristics and Risk Assessment in Multigate Dam-type River].","authors":"Tian-Yi Sun, Jia-Chen Shen, Dian-Peng Li, Shu-Qing An, Xin Leng","doi":"10.13227/j.hjkx.202306062","DOIUrl":"https://doi.org/10.13227/j.hjkx.202306062","url":null,"abstract":"<p><p>Microplastics pose a serious ecological threat to rivers in China, and the construction of a large number of dams has complicated this problem. Ten dams of the Shaying River were chosen to investigate the abundance and composition of microplastics in surface water and sediments of the reservoir and upstream river. Ecological risk was evaluated using species sensitive distribution (SSD) and pollution load index (PLI). The results showed that the Shaying River was exposed to a severe risk of microplastics from upstream to downstream. The construction of dams did not significantly affect the distribution of microplastics in the river. River sediments became a sink for microplastics in the surface water; however, the ecological risk posed by microplastics in the surface water was greater, and the comparison of the two assessment methods showed that the species sensitivity distribution assessment better reflected the accumulation and feeding behavior of organisms to pollutants compared to the pollution load index.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142018988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Adsorption and Desorption Behavior of PAEs Plasticizer on PVC and Rubber Particles After Natural Environment Aging].","authors":"Si-Fu Zhu, Jian-Chao Liu, Guang-Hua Lu","doi":"10.13227/j.hjkx.202309168","DOIUrl":"https://doi.org/10.13227/j.hjkx.202309168","url":null,"abstract":"<p><p>Microplastics (MPs) coexist with plasticizers in the aqueous environment to form composite pollution, but the adsorption and desorption behaviors of MPs and plasticizers under natural conditions are unknown. Polyvinyl chloride (PVC) and rubber were used as the target MPs to characterize the changes in their morphological features after aging for one anniversary in atmospheric exposure and lake sedimentary burial environments and to investigate the adsorption and desorption behavior of the MPs to the coexisting phthalate esters (PAEs) plasticizer before and after aging. The results showed that the surface of MPs was rougher after exposure to the atmospheric environment and burial in a depositional environment, showing the characteristics of porous polymers. The carbonyl index (CI) of PVC and rubber increased by 62.2% and 321.2%, respectively, in the atmospheric environment and increased by 51.1% and 223.1%, respectively, in the depositional environment. The atmospheric exposure was capable of accelerating the aging process of MPs. PAEs were adsorbed on the surface of MPs through hydrophobic interaction, and the amount of adsorption was significantly and positively correlated with their hydrophobic properties. The adsorption capacity and adsorption rate of PVC on PAEs were inhibited after aging. Aging promoted the adsorption of rubber on strongly hydrophobic PAEs plasticizers and inhibited the adsorption of weakly hydrophobic PAEs. The environmental aging process reduced the desorption of strongly hydrophobic PAEs from rubber, enhanced the reversibility of rubber adsorption of weakly hydrophobic PAEs, and increased the desorption rate of PAEs from PVC.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142018923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shi-Yi Wang, Yan Li, Jia-Yu Yang, Er Yu, Kai-Ge Lei, Xin-Hui Feng
{"title":"[Land Use Change Driving and Optimization of Carbon Budget in Hangzhou Metropolitan Area].","authors":"Shi-Yi Wang, Yan Li, Jia-Yu Yang, Er Yu, Kai-Ge Lei, Xin-Hui Feng","doi":"10.13227/j.hjkx.202309054","DOIUrl":"https://doi.org/10.13227/j.hjkx.202309054","url":null,"abstract":"<p><p>As climate change, such as global warming, has become a global environmental issue, clarifying the mechanism driving the carbon budget based on land use change has become an inevitable path to realize the \"double carbon\" goal. Based on the land use change characteristics in the Hangzhou Metropolitan Area from 1995 to 2020, this study employed the inventory accounting method, concentration index, and panel regression models to investigate the driving mechanisms of carbon budget dynamics influenced by land use changes. Moreover, the study utilized a \"scenario-actor\" policy analysis framework to propose low-carbon strategies through the integration of land use management within territorial spatial planning. The research findings were as follows: ① The carbon source capacity in the study area significantly surpassed its carbon sink capacity. The overall carbon budget concentration index had yet to exceed the 0.4 \"alert threshold,\" with spatial concentration levels as follows: Hangzhou > Huangshan > Shaoxing > Quzhou > Jiaxing ≈ Huzhou. ② For croplands, larger areas and greater shape regularity contributed to a reduction in carbon budgets. Conversely, for constructed lands, expansive areas and increased fragmentation intensified the carbon budget levels, primarily driven by other urban land categories. ③ An increased proportion of croplands and higher land use heterogeneity promoted spatial equilibrium in carbon budgets, whereas the larger coverage and fragmentation of industrial and other urban lands led to an uneven spatial distribution of carbon budgets. ④ Low-carbon optimization of territorial space needs to adjust for the structure and form of carbon source functional land use as a key driver. At the policy implementation level, the central government and urban residents demonstrated strong support for low-carbon territorial control. However, cooperation from local governments, enterprises, and rural residents was suboptimal, necessitating complementary policies for effective guidance. This study holds practical significance for enhancing land use efficiency and promoting low-carbon urban development.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142018969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Multi-objective Identification Method for Influencing Factors of Soil Heavy Metal Content Change].","authors":"Xiang-Nan Guan, Shi-Wei Dong, Yu Liu, Xin-Xin Zhang, Yu-Chun Pan, Chuang Lu","doi":"10.13227/j.hjkx.202308194","DOIUrl":"https://doi.org/10.13227/j.hjkx.202308194","url":null,"abstract":"<p><p>Identifying the influencing factors of soil heavy metal content changes is the basis for reducing or preventing soil heavy metal pollution. Taking an agricultural experimental field in Changping District of Beijing as an example, the heavy metal content changes in As, Cr, Cu, Ni, Pb, and Zn from 2012 to 2022 were firstly analyzed. Secondly, the influencing factors of the heavy metal content changes were detected based on the geographical detector at the single-target and multi-target levels, respectively. Finally, comparative experiments with the correlation analysis method and existing studies were set up to evaluate the effectiveness of the identification method of influencing factors developed in this study. The results showed that human activity factors have exacerbated the changes in soil heavy metal content in the study area as follows: ① At the single-target level, the land use type was the main influencing factor on the changes in Cr, Cu, and Zn contents, and the annual deposition flux influenced the changes in As. The results of the interaction detection showed that there was an enhancement effect among the factors, and the interaction of the human activity factors dominated for the factor identification. ② The results of the multi-target level detection covered the results of the single-target level detection, which could identify more influencing factors. The land use type affected the changes in Cu, Zn, Cr, Ni, and As, and the changes in As and Zn were influenced by the annual deposition fluxes. ③ The multi-target identification method coupled with geographical detector and principal component analysis could effectively identify the influencing factors of soil heavy metal content changes, which was much more effective than the single soil heavy metal correlation method. The developed multi-target identification method for influencing factors of heavy metal content changes can provide technical support for the regional pollution monitoring and macro-management of soil heavy metals.</p>","PeriodicalId":35937,"journal":{"name":"Huanjing Kexue/Environmental Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142018989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}