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Paleoenvironmental changes recorded by grain size of loess/paleosol sequence from the Chifeng City,Northeastern China since the Last Glacial
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作者 LI Juan BRYE Kristofor R +2 位作者 ZHANG Mengge JIANG Zhuodong WANG Qiubing 《Journal of Mountain Science》 SCIE CSCD 2024年第9期3068-3082,共15页
The accumulation processes of loess in northeastern(NE)China record the varying characteristics of the East Asian Monsoons(EAM)and the evolution of the local environment.In this study,grain size end-member analysis of... The accumulation processes of loess in northeastern(NE)China record the varying characteristics of the East Asian Monsoons(EAM)and the evolution of the local environment.In this study,grain size end-member analysis of the Dajiugang(DJG)section deposited since the Last Glacial in Chifeng City,NE China was used to reveal the dynamic depositional characteristics of loess and environmental evolution of NE China.Results showed that the Chifeng loess comprises three grain size end-members(EM),EM1(7.38μm),EM2(49.4μm)and EM3(90.00μm),indicating the three transport dynamics of dust delivered to the region.The EM1 represents atmospheric dust as the background.The EM2,mainly derived from relatively distant-sources deposition,and EM3,material transported over a short distance,correspond to the intensity of southwesterly winds and the East Asian Winter Monsoon(EAWM),respectively.Results of climate reconstruction,combined with other records,showed that the climate was generally cold and dry with a strong EAWM and a weak East Asian summer monsoon(EASM)during the stadial-period[Marine Isotope Stage(MIS)4 and MIS 2 stage].The climate was predominantly warm and humid,with weak EAWM and surface winds and strong EASM in interstadial-period(MIS 3 and MIS 1 stage).Comparisons between indicators,e.g.,EM3,the LR04 benthicδ18O stack and summer insolation at 65°N suggest that the strong EAWM is induced by increasing the Northern Hemisphere ice volume and reduced summer solar radiation. 展开更多
关键词 Loess deposit Grain size end-member Northeastern China environmental change The Last Glacial
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Historical Changes,Contemporary Characteristics,and Five Transformations of Environmental Design in China
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作者 Tijin Gui 《Journal of Contemporary Educational Research》 2024年第7期7-17,共11页
Starting from the characteristics of modernization in three different historical stages since the founding of the People’s Republic of China,this paper analyses the internal changes in the professional name,subordina... Starting from the characteristics of modernization in three different historical stages since the founding of the People’s Republic of China,this paper analyses the internal changes in the professional name,subordinate disciplines and categories,and professional mission of the environmental design profession,and summarizes the changes in the characteristics of the environmental design profession in 10 aspects such as subordinate disciplines,design objects,design types,cultural characteristics,and aesthetic values on the basis of the results of the analysis,and explores five transformations of the environmental design profession in the process of China’s development in the future.The five transformations in the future development of China are to serve the harmony and beauty of the three major urban and rural spaces with“small and micro-renewal and reconstruction”;to serve the transmission of Chinese culture and the spread of Chinese civilization with“spatial heritage and innovation”;to serve the balance and sufficiency of the four functions of urban and rural settlements with“friendliness and equilibrium”;to serve the intelligence,wisdom,and enjoyment of indoor and outdoor living environment space with“scientific and technological achievements”;and to serve the co-construction,co-management,and sharing of indoor and outdoor public space in urban and rural areas with“public participation.” 展开更多
关键词 environmental design Historical changes Contemporary characteristics Five transformations
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Responses of breeding waterbird communities to environmental changes in subsidence wetlands in the North China Plain 被引量:1
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作者 Guangyao Wang Jinming Zhao +4 位作者 Weiqiang Li Xiangrong Song Yong Zhang Chunlin Li Willem F.de Boer 《Avian Research》 SCIE CSCD 2023年第3期336-344,共9页
In the context of global degradation and loss of natural wetlands,waterbirds have been increasingly using artificial wetlands as alternative habitats.However,waterbirds are facing various threats in these artificial w... In the context of global degradation and loss of natural wetlands,waterbirds have been increasingly using artificial wetlands as alternative habitats.However,waterbirds are facing various threats in these artificial wetlands,due to dramatic environmental changes induced by anthropogenic activities.Exploring the effects of these changes on the temporal dynamics of the waterbird communities can help understand how waterbirds adapt to environmental changes and thus formulate effective management and conservation plans.In this study,we carried out field surveys on waterbirds and environmental factors across 20 subsidence wetlands created by underground coal mining in the Huainan coal mining area in the breeding seasons of 2016 and 2021.We predicted that the waterbird assemblages(i.e.,number of individuals,species richness,Shannon-Wiener diversity,Pielou evenness and species composition) differed between the two years,and that these differences were correlated with the temporal changes in environmental factors.Across the surveyed wetlands,we recorded 26 waterbird species in 2016 and 23 in 2021.For individual wetlands,the number of waterbird individuals and species richness increased by 71.6% and 20.1%,respectively,over the five years,with no changes in Shannon-Wiener diversity and Pielou evenness.The overall increase in the number of bird individuals was mainly caused by an increase in vegetation gleaners and gulls that adapt well to anthropogenic activities.The species composition was significantly different between the two years,which was mainly caused by changes in the number of individuals of dominant species under influence of changes in human activities.For most wetlands,the temporal pairwiseβ-diversities could be explained by species turnover rather than nestedness,probably due to high mobility of waterbird species and dramatic changes in local environments.Our study suggests that waterbird communities could respond to environmental changes in subsidence wetlands,providing important implications for waterbird conservation in human-dominated artificial wetlands. 展开更多
关键词 Artificial wetlands environmental changes Subsidence wetlands Waterbird community
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Challenges and Countermeasures for Integrating the Protection of Environmental Rights into Actions for Addressing Climate Change
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作者 秦天宝 袁野阳光 《The Journal of Human Rights》 2023年第4期869-893,共25页
Climate change,which is the result of human activities,has wide-ranging impact.It poses a serious threat to human rights.Environmental rights are where the protection of the ecological environment and the development ... Climate change,which is the result of human activities,has wide-ranging impact.It poses a serious threat to human rights.Environmental rights are where the protection of the ecological environment and the development of human rights intersect.In view of the close relationship between the actions for addressing climate change and environmental rights,China should integrate the protection of environmental rights into the actions for addressing climate change,so as to achieve simultaneous development of both.In the process of coping with climate change,the right to climate stability that mainly pursues a“harmless”environment and the right to a more livable climate that pursues a“beautiful eco-environment”are specific manifestations of environmental rights and should be the priority of protection efforts.However,there are still some obstacles to achieving the coordinated development of the efforts to address climate change and the protection of environmental rights because traditional rights protection methods mainly give individuals subjective rights with the power to claim and are thus difficult to meet the needs of environmental rights protection in the context of climate change,and there are inherent value differences between responding to climate change and the realization of other human rights.Building a multi-level national obligation system to address climate change,giving full play to the role of courts in responding to climate change through moderate judicial activism,and coordinating the efforts to cope with climate change and the development of human rights under the guidance of a holistic system view are effective ways to overcome the aforementioned difficulties. 展开更多
关键词 actions for addressing climate change environmental rights judicial activism holistic system view
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Environmental Changes Analysis of Hongjiannao Lake During Recent Fifty Years——Based on the Data of Lake Sediments 被引量:6
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作者 李双 陈硕 张家武 《Agricultural Science & Technology》 CAS 2009年第6期178-183,共6页
Particle size, the contents of carbonate and TOC were analyzed on lake sediments from a short core in Hongjiannao Lake to discuss the environmental changes during the past decades. On the basis of the records in lake ... Particle size, the contents of carbonate and TOC were analyzed on lake sediments from a short core in Hongjiannao Lake to discuss the environmental changes during the past decades. On the basis of the records in lake sediments and comparison with the meteorological data of Yulin region, the environmental changes in Hongjiannao Lake were approximately divided into two stages. In stage A (1957 -1996), the lake evolution and the environmental change were mainly influenced by natural factors. It contains three sub-stages: A1 (1957-1969), a period of lake expansion, A2 (1969-1990), a stable period with high lake levels, and A3 (1990 -1996), a period of gradual extraction of the lake. In stage B (1996 -2005), the lake area still keeps diminishing. During this period, organic matter increased rapidly due to the input of nutrient elements in the catchment. The carbonate content, however, decreased. As the precipitation was decreasing and the temperature was increasing, the decrease of carbonate content could not be explained by either temperature or precipitation change. 展开更多
关键词 Hongjiannao Lake Particle size TOC CARBONATE environmental changes
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Comprehensive Evaluation of Environmental Effects from Land Change in Hotan Oasis,Xinjiang 被引量:5
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作者 杨依天 王乃河 王平 《Agricultural Science & Technology》 CAS 2014年第4期653-658,共6页
[Objective] This study aimed to evaluate the environmental effects coming from land changes in Hotan oasis during 1980-2010. [Method] Based on the Driving Force-State-Response model, expert weight method and entropy m... [Objective] This study aimed to evaluate the environmental effects coming from land changes in Hotan oasis during 1980-2010. [Method] Based on the Driving Force-State-Response model, expert weight method and entropy method were used to determine weight, and then the composite indexes of environmental effects (CIE for short) were calculated. [Result] During the period from 1980 to 2010, CIE had presented a rising trend whether expert weight method or entropy method in the study area, while the CIE presents downtrend basically in lower reaches. [Conclu- sion] It was the arable land expansion in middle reaches that led to serious land degradation in lower reaches, and may endanger ecosystem safety in Hotan River green corridor. Therefore, it is suggested that the agricultural land use should be restructured, such as reducing the sown areas of some crops with large amount of water consumption. Meanwhile, the effective measures should be taken to distribute water resources and utilize them reasonably. In addition, the oasis-desert ecotone, as well as the groundwater resources, should be also protected. 展开更多
关键词 Comprehensive evaluation environmental effects Land change Hotan Oasis
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Volcanically Driven Terrestrial Environmental Perturbations during the Carnian Pluvial Episode in the Eastern Tethys
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作者 Naveed Ur RAHMAN XIAN Benzhong +4 位作者 FANG Linhao CHEN Sirui CHEN Peng Zaheen ULLAH WANG Pengyu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期753-770,共18页
The Carnian Pluvial Episode(CPE)fingerprints global environmental perturbations and biological extinction on land and oceans and is potentially linked to the Wrangellia Large Igneous Province(LIP).However,the correlat... The Carnian Pluvial Episode(CPE)fingerprints global environmental perturbations and biological extinction on land and oceans and is potentially linked to the Wrangellia Large Igneous Province(LIP).However,the correlation between terrestrial environmental changes and Wrangellia volcanism in the Ordos Basin during the CPE remains poorly understood.Records of negative carbon isotopic excursions(NCIEs),mercury(Hg),Hg/TOC,and Hg enrichment factor(HgEF)from oil shales in a large-scale terrestrial Ordos Basin in the Eastern Tethys were correlated with marine and other terrestrial successions.The three significant NCIEs in the study section were consistently correlated with those in the CPE successions of Europe,the UK,and South and North China.The U-Pb geochronology indicates a Ladinian-Carnian age for the Chang 7 Member.A comprehensive overview of the geochronology,NCIE correlation,and previous bio-and chronostratigraphic frameworks shows that the Ladinian-Carnian boundary is located in the lower part of Chang 7 in the Yishicun section.HgEF may be a more reliable proxy for tracing volcanic eruptions than the Hg/TOC ratio because the accumulation rates of TOC content largely vary in terrestrial and marine successions.The records of Hg,Hg/TOC,HgEF,and NCIEs in the Ordos Basin aligned with Carnian successions worldwide and were marked by similar anomalies,indicating a global response to the Wrangellia LIP during the CPE.Anoxia,a warm-humid climate,enhancement of detrital input,and NCIEs are synchronous with the CPE interval in the Ordos Basin,which suggests that the CPE combined with the regional Qinling Orogeny should dominate the enhanced rate of terrigenous input and paleoenvironmental evolution in the Ordos Basin. 展开更多
关键词 chang 7 Member oil shale Carnian Pluvial Episode VOLCANISM environmental perturbations
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Is economic fitness helpful in achieving environmental sustainability in BRICS economies?A risk exposure perspective
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作者 Jabbar Ul-Haq Hubert Visas +2 位作者 Muhlis Can Qazi Muhammad Adnan Hye Noreen Aslam 《Chinese Journal of Population,Resources and Environment》 2024年第2期109-117,共9页
A country’s ability to create complex goods and diversify its lines of products is essential for addressing all types of vulnerabilities.Quantifying a country’s vulnerability to extreme climatic events,such as droug... A country’s ability to create complex goods and diversify its lines of products is essential for addressing all types of vulnerabilities.Quantifying a country’s vulnerability to extreme climatic events,such as droughts,superstorms,and other natural disasters,and its capacity for successful adaption,is an essential global need that has been ignored.This study examines the role of economic fitness(EF)in addressing climate change risk ex‐posure in BRICS countries in the context of the environmental Kuznets curve using panel data from 1995 to 2015.Panel threshold methodology is employed to ascertain the nonlinear relationship between EF and climate change risk exposure(i.e.,Notre Dame Global Adaptation Initiative Country Index(ND-GAIN)).In addition,empirical associations were estimated using panel-corrected standard errors,Driscoll-Kraay standard errors,and feasible generalized least squares estimation techniques.These findings demonstrated an inverted N shaped link between EF and ND-GAIN.Moreover,even after controlling for significant ND-GAIN influencing variables such as gross domestic product per capita,financial development,and urbanization,our robustness checks revealed significant and consistent findings. 展开更多
关键词 Economic fitness Climate change BRICS countries environmental Kuznets Curve Notre Dame Index
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The Role of Certificates and Labels for Cocoa in the Face of Climate Change: A Scientific Review
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作者 Charles Hans Opoku 《American Journal of Climate Change》 2024年第2期281-313,共33页
Climate change threatens cocoa quality, raising concerns regarding sustainable premium cocoa production. Evaluating the effectiveness of certification standards is imperative to address this concern effectively. A mul... Climate change threatens cocoa quality, raising concerns regarding sustainable premium cocoa production. Evaluating the effectiveness of certification standards is imperative to address this concern effectively. A multi-stage method was employed for a systematic review of 39 peer-reviewed articles to highlight the impacts of climate change on the biophysical environment of cocoa and its implications for adapting Geographical Indications (GIs). Additionally, a comprehensive review was conducted on climate-relevant standards of certificates in Ecuador, Indonesia, and Ghana. The findings of this study provide practical insights into possible difficulties that cocoa-producing countries may encounter in maintaining the distinctive flavours and quality trademarks of cocoa in the face of changing climate. Moreover, the findings emphasize the need for producer countries to prioritize viable adaptation and product differentiation strategies that meet sustainable marketing standards to protect GIs or place-based intellectual property. Furthermore, the findings indicate certificates require effective multi-level climate change management and environmental-social-governance principles that promote scientifically proven mitigation strategies, such as increasing soil organic carbon, zero deforestation, and reducing emissions while striving to leverage local adaptation policies to reduce location-specific vulnerability. Finally, certificates can accelerate the expansion, intensification, and redistribution of sustainable production for gains that outweigh the inconveniences caused by climate change. 展开更多
关键词 ADAPTATION Biophysical environment Climate change Cocoa Certificates environmental Social Governance MITIGATION Geographical Indications
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Environmental and Climate Justice in Palestine
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作者 Jad Isaac Jane Hilal 《American Journal of Climate Change》 2024年第2期251-280,共30页
To have a clean, safe, and functional environment is not only essential for the purpose of preservation, but also imperative for safeguarding the most fundamental of human rights. Resolution 45/94 of the United Nation... To have a clean, safe, and functional environment is not only essential for the purpose of preservation, but also imperative for safeguarding the most fundamental of human rights. Resolution 45/94 of the United Nations (UN) General Assembly also stresses and acknowledges that: “all individuals are entitled to live in an environment adequate for their health and wellbeing” (United Nations Digital Library System, 1991). Environmental and climate justice, which: “emerged in the context of the local environmental struggles of directly oppressed groups”, is a global movement dedicated to ensuring equal protection of people’s human rights (i.e., water, health, life, etc.) in the face of the climate crisis. Moreover, health, environment and human rights are part of the 2030 agenda (in particular, SDG 1, SDG 5, SDG 6, SDG 7, SDG 13, SDG 16, SDG 17). Individually, both environmental and climate justice are rooted in an intersectional outlook, by which they highlight the common threads between communities and the people’s inclusion, irrespective of race, class, or gender, in the pursuit of justice. On the other hand, they recognise and acknowledge the role and consequences of climate change in economic, social, and political dimensions;thus, drawing emphasis on the rights of people under the emerging inequities. In the case of Palestine, the Palestinian community is increasingly becoming vulnerable to these effects and the resulting inequalities of climate change. This vulnerability stems from: 1) The right to life;clean WASH;equitable work opportunities;access to resources;and free movement;are all examples of human rights that the Israeli colonial regime infringes upon;2) Infrastructure is essential for climate adaptation: 61% of the West Bank is ultimately barred from building infrastructure (B’Tselem, 2019) and Gaza Strip has major gaps in infrastructure due to intentional destruction by Israel;3) Palestinian deprivation of the sovereign right to natural resources by Israel;4) Apartheid system in water accessibility: Israeli water usage per person is over three times higher than that of Palestinians (their usage is under the WHO recommended minimum per day) (B’Tselem, 2023);and 5) Violent settler attacks. In 2022 alone, the Applied Research Institute-Jerusalem (ARIJ) recorded 1527 settler attacks that targeted land, properties, livestock, agriculture and even Palestinian civilians. The ongoing neglect of these concerns and the persistent colonization of Palestine by Israel unequivocally and unwaveringly affect the human rights of Palestinians. The power dynamics at play especially hamper the Palestinian ability to exercise and fulfill their inalienable human rights and to tackle the obstacles to justice in their environment. 展开更多
关键词 environmental Degradation Climate change environmental and Climate Justice Human Rights Causes and Solution
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Climate change and human health: Last call to arms for us
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作者 Antonio Corrente Maria Caterina Pace Marco Fiore 《World Journal of Clinical Cases》 SCIE 2024年第11期1870-1874,共5页
Climate change,now the foremost global health hazard,poses multifaceted challenges to human health.This editorial elucidates the extensive impact of climate change on health,emphasising the increasing burden of diseas... Climate change,now the foremost global health hazard,poses multifaceted challenges to human health.This editorial elucidates the extensive impact of climate change on health,emphasising the increasing burden of diseases and the exacerbation of health disparities.It highlights the critical role of the healthcare sector,particularly anaesthesia,in both contributing to and mitigating climate change.It is a call to action for the medical community to recognise and respond to the health challenges posed by climate change. 展开更多
关键词 Climate change Carbon footprint Sustainability Greenhouse gases Anaesthetic gases environmental impact Disposable laryngoscope blades
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Eternal Climate Change Patterns and the Causes and Countermeasures of Global Climate Change
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作者 Cuixiang Zhong 《Journal of Environmental Science and Engineering(B)》 2024年第1期9-20,共12页
It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summari... It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summarized the 24 solar terms by observing the annual activities of the sun for a long time,because they ignored the impact of the activities of the moon on the Earth’s climate change on a small scale,the 24 solar terms they summarized often could not accurately predict the change of the Earth’s climate.Therefore,the author studied the influence of lunar activities on the Earth’s climate change,finds out the law of the influence of lunar activities on the Earth’s climate change on a small scale,and summarizes the eternal climate change pattern determined by the activities of the sun and the moon.In addition,the author also reveals the causes and countermeasures of global warming and the frequent occurrence of extreme weather as well as environmental change. 展开更多
关键词 Eternal climate change patterns global warming extreme weather abrupt environmental changes CAUSES countermeasures.
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Migration and Spatiotemporal Land Cover Change: A Case of Bosomtwe Lake Basin, Ghana
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作者 Richard Kwabena Adams Lingling Zhang Zongzhi Wang 《Advances in Remote Sensing》 2024年第1期18-40,共23页
Internal migration is highly valued due to its increasingly acknowledged potential for social and economic development. However, despite its significant contribution to the development of towns and cities, it has led ... Internal migration is highly valued due to its increasingly acknowledged potential for social and economic development. However, despite its significant contribution to the development of towns and cities, it has led to the deterioration of many ecosystems globally. Lake Bosomtwe, a natural Lake in Ghana and one of the six major meteoritic lakes in the world is affected by land cover changes caused by the rising effects of migration, population expansion, and urbanization, owing to the development of tourist facilities on the lakeshore. This study investigated land cover change trajectories using a post-classification comparison approach and identified the factors influencing alteration in the Lake Bosomtwe Basin. Using Landsat imagery, an integrated approach of remote sensing, geographical information systems (GIS), and statistical analysis was successfully employed to analyze the land cover change of the basin. The findings show that over the 17 years, the basin’s forest cover decreased significantly by 16.02%, indicating that population expansion significantly affects changes in land cover. Ultimately, this study will raise the awareness of stakeholders, decision-makers, policy-makers, government, and non-governmental agencies to evaluate land use development patterns, optimize land use structures, and provide a reference for the formulation of sustainable development policies to promote the sustainable development of the ecological environment. 展开更多
关键词 Land Cover change Supervised Classification MIGRATION Landsat Imagery environmental Sustainability
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Dynamic Changes of Nitrogen in Saline-alkaline Paddy Field and Its Potential Environmental Impacts 被引量:1
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作者 叶洁琼 袁瑞霞 +1 位作者 王兆慧 柳建设 《Agricultural Science & Technology》 CAS 2011年第3期443-446,460,共5页
[Objective] The paper was to study the dynamic changes of nitrogen in saline-alkaline paddy field and its potential environment impacts. [Method] With typical sodic saline-alkaline paddy fields of Songnen Plain as stu... [Objective] The paper was to study the dynamic changes of nitrogen in saline-alkaline paddy field and its potential environment impacts. [Method] With typical sodic saline-alkaline paddy fields of Songnen Plain as study object,field test method was used to explore the dynamic changes was strong alkof nitrogen in paddy field of the region and its potential impact on environment. [Result] The soil in test regionaline with high CEC and C/N ratios,as well as poor preserving capacity of fertilizer. During the two-year field experiment,the indicators of salinization fluctuated. Initially,the concentrations of total nitrogen and ammonia nitrogen reached their maximum values,then decreased over time as a result of heavy rain. The maximum of nitrate concentration appeared later than those of total nitrogen and ammonia nitrogen. Ammonia volatilization accounted for 18.9%-28.8% of the nitrogen loss. The total nitrogen concentration in surface water was higher than the national Class Ⅲ surface water environmental quality standard. The concentration of ammonia from the recession flow of agricultural field was considerably high,which would potentially threaten the fishery in the downstream of Chagan Lake. [Conclusion] The study provided theoretical basis for saline-alkaline soil management and conservation of water and fishery resources. 展开更多
关键词 Saline-alkaline soil NITROGEN Dynamic changes Potential environmental impact
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Pro-Environmental Civic Participation in the USA: The Effects of Social Media, Pro-Environmental Lifestyle and Climate Experiences
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作者 Rita Mano 《American Journal of Climate Change》 2024年第1期31-46,共16页
This study addresses the link between social media use and pro-environmental civic participation considering the moderating effect of social media affordances (public realm) on one hand, and lifestyle behaviors and cl... This study addresses the link between social media use and pro-environmental civic participation considering the moderating effect of social media affordances (public realm) on one hand, and lifestyle behaviors and climate change experiences (personal realm) on the other. We combine communication theory and behavioral models and using a sample of USA individuals (N = 7225) based on the American Trends Panel to predict variations in pro-environmental behavior. We show that social networks rather than information are more effective in predicting pro-environmental behavior. Moreover, a pro-environmental lifestyle as well as climate change experiences at the community level increase the likelihood for pro-environmental participation. However, affordances related to socioeconomic variations generate variations to pro-environmental civic participation. We conclude that in order to capture the depth of pro-environmental civic participation, it is necessary to theoretically and empirically bridge between private and public expressions of pro-environmental awareness. 展开更多
关键词 Pro-environmental Behavior SOCIO-ECONOMIC Digital Information Digital Networks Private Expressions Public Expressions Climate changes USA
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Paleoenvironmental changes during the late Quaternary as inferred from foraminifera assemblages in the Laizhou Bay 被引量:7
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作者 YAO Jing YU Hongjun +3 位作者 XU Xingyong YI Liang CHEN Guangquan SU Qiao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第10期10-18,共9页
Controlled by climate changes, there were three large-scale transgressions and regressions around the Bohai Sea during the late Quaternary, which were accepted by most geologists. However, a big controversy still exis... Controlled by climate changes, there were three large-scale transgressions and regressions around the Bohai Sea during the late Quaternary, which were accepted by most geologists. However, a big controversy still exists about the time when the transgressions occurred separately. In order to find out the process of the paleoenvironmental changes around the Bohai Sea in the late Quaternary, the foraminifera assemblages from a new borehole Lz908 in the southern coast of the Laizhou Bay were studied, and then the transgressive strata were indentified. Combined with accelerator mass spectrometry radiocarbon 14C(AMS14C) and optically stimulated luminescence(OSL) ages, the occurrence time of these transgressions were re-determined. The result showed that three major large-scale transgressions occurred separately at the beginning of marine isotopic stage 7(MIS7), the last interglacial period(MIS5) and the Holocene. In addition, a small-scale transgression occurred in the mid-MIS6, and the corresponding transgressive stratum was deposited. The transgressive deposition of MIS3 was also discovered in this study. However, the characteristics of the foraminifera indicated the environment during this period was colder than that in the MIS5. By comparison with the global sea-level changes, the paleoenvironmental changes around the Bohai Sea in the late Quaternary can be consistent with the global climate changes. 展开更多
关键词 foraminifera assemblage late Quaternary environmental changes Laizhou Bay Bohai Sea
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Environmental change and cultural response around 4200 cal. yr BP in the Yishu River Basin, Shandong 被引量:7
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作者 GAO Huazhong ZHU Cheng XU Weifeng 《Journal of Geographical Sciences》 SCIE CSCD 2007年第3期285-292,共8页
Neolithic culture series in the Yishu River Basin developed in the order of Beixin culture-Dawenkou culture-Longshan culture-Yueshi culture. During the early and middle stage of Longshan culture (4600-4300 cal. yr BP... Neolithic culture series in the Yishu River Basin developed in the order of Beixin culture-Dawenkou culture-Longshan culture-Yueshi culture. During the early and middle stage of Longshan culture (4600-4300 cal. yr BP), the climate in the Yishu River Basin was warm and wet. Paddy-oriented agriculture planted paddy was very developed. The society was flourishing with great amount of archaeological sites. The cooling starting in 4200 cal. yr BP made the paddies shortfall in output or even no seeds were gathered. This situation intensified the discrepancy between population and resource. The scarcity in natural resource led to substantial decrease in population and subsequent drop in archaeological sites. About 4000 cal. yr BP Longshan culture was displaced by Yueshi culture which was relatively un- derdeveloped, simple and unsophisticated. 展开更多
关键词 Yishu River SHANDONG 4200 cal. yr BP environmental change cultural response
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The sources and composition of organic matter in sediments of the Jiaozhou Bay:implications for environmental changes on a centennial time scale 被引量:5
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作者 KANG Xuming SONG Jinming +3 位作者 YUAN Huamao LI Xuegang LI Ning DUAN Liqin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第11期68-78,共11页
The Jiaozhou Bay is characterized by heavy eutrophication that is associated with intensive anthropogenic activities. Four core sediments from the Jiaozhou Bay are analyzed using bulk technologies, including sedimenta... The Jiaozhou Bay is characterized by heavy eutrophication that is associated with intensive anthropogenic activities. Four core sediments from the Jiaozhou Bay are analyzed using bulk technologies, including sedimentary total organic carbon(TOC), total nitrogen(TN), the stable carbon(δ13C) and nitrogen(δ15 N) isotopic composition to obtain the comprehensive understanding of the source and composition of sedimentary organic matter and further shed light on the environmental changes of the Jiaozhou Bay on a centennial time scale.Results suggest that the TOC and TN concentrations increase in the upper core, having indicated a probable eutrophication process since the 1920 s in the inner bay and the 2000 s in the bay mouth. The TOC and TN concentrations outside the bay have also changed since 1916 owing to the variation of terrigenous input.Considering TOC/TN ratio, δ13 C and δ15 N, it can be concluded there is a mixture of terrigenous and marine organic matter sources in the study area. A simple two end-member(terrigenous and marine) mixing model usingδ13 C indicats that 45%–79% of TOC in the Jiaozhou Bay is from the marine source. The environmental changes of the Jiaozhou Bay are recorded by geochemical proxies, which are influenced by the intensive anthropogenic activities(e.g., extensive use of fertilizers, and discharge of sewage) and climate changes(e.g., rainfall). 展开更多
关键词 organic matter SOURCES anthropogenic activities environmental changes SEDIMENTS Jiaozhou Bay
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Environmental change since mid-Pleistocene recorded in Shangshan achaeological site of Zhejiang 被引量:6
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作者 MAO Longjiang MO Duowen +5 位作者 JIANG Leping JIA Yaofeng LIU Xiaoyan LI Minglin ZHOU Kunshu SHI Chenxi 《Journal of Geographical Sciences》 SCIE CSCD 2008年第2期247-256,共10页
At about 173 ka BP of the late period of mid-Pleistocene, the second terrace of the river had been formed as a result of uplift happening in Shangshan area because of the climate, sea level change and tectonic action.... At about 173 ka BP of the late period of mid-Pleistocene, the second terrace of the river had been formed as a result of uplift happening in Shangshan area because of the climate, sea level change and tectonic action. Between 173-75 ka BP, aeolian deposited on the terrace, a layer of reticulate red clayey soil about 80-100 cm thick deposited and developed under the warmer and higher temperature. In the last glacial period, the drop of the temperature and the decrease of the precipitation induced the dust-storms increased, A layer of Xiashu loess about 1.0-1.5 m thick accumulated on Shangshan terrace in the last glacial, which has the reticulate red clayey soil buried. At the beginning of the Holocene (11500 a BP-), temperature went higher gradually and precipitation got more, the pre-persons moved on the Shangshan terrace (11,400-8600 a BP), which is one of the most important archaeological sites, and can connect the paleolithic culture with Neolithic culture. It could be assumed from the results that the lower reaches of the Yangtze River are the home of rice cultivation, too. The lower place to the west of the Shangshan site experienced the two cycles process of the fluvial facies and the lacustrine facies, indicating that the water source of the pre-historical Shangshan is the river water or lake water. Two AMS 14C age proved the water source disappeared more than 1000 years ago. 展开更多
关键词 environmental change reticulate red clay TL/OSL dating mid-Pleistocene Shangshan culture ZHEJIANG
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Soil Organic Carbon and Labile Carbon Along a Precipitation Gradient and Their Responses to Some Environmental Changes 被引量:12
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作者 WANG Shu-Ping ZHOU Guang-Sheng +1 位作者 GAO Su-Hua GUO Jian-Ping 《Pedosphere》 SCIE CAS CSCD 2005年第5期676-680,共5页
Based on data from a field survey in 2001 along the Northeast China transect (NECT), a precipitation gradient,and a short-term simulation experiment under ambient CO2 of 350 μmol mol-1 and doubled CO2 of 700 μmol mo... Based on data from a field survey in 2001 along the Northeast China transect (NECT), a precipitation gradient,and a short-term simulation experiment under ambient CO2 of 350 μmol mol-1 and doubled CO2 of 700 μmol mol-1with different soil moisture contents of 30%-45%, 45%-60%, and 60%-80% soil water holding capacity, the distributionof soil organic carbon and labile carbon along the NECT, their relationships with precipitation and their responses toCO2 enrichment and soil moisture changes were analyzed. The results indicated that the soil labile carbon along thegradient was significantly related to soil organic carbon (r = 0.993, P < 0.001). The soil labile carbon decreased morerapidly with depth than organic carbon. The soil organic and labile carbon along the gradient decreased with decrease inlongitude in both the topsoils and subsoils, and the coefficient of variation for the labile carbon was greater than that forthe organic carbon. Both the soil organic carbon and labile carbon had significant linear relationships with precipitation,with the correlation coefficient of soil organic carbon being lower (0.677 at P < 0.001) than that of soil labile carbon(0.712 at P < 0.001). In the simulation experiment with doubled and ambient CO2 and different moisture contents, thecoefficient of variation for soil organic carbon was only 1.3%, while for soil labile carbon it was 29.7%. With doubled CO2concentration (700 μmol mol-1), soil labile carbon decreased significantly at 45% to 60% of soil moisture content. Theseindicated that soil labile carbon was relatively more sensitive to environmental changes than soil organic carbon. 展开更多
关键词 environmental changes labile carbon organic carbon precipitation gradient SOIL
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