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The Impacts of Louisiana’s Changing Climate on Food Crop Production
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作者 Yaw A. Twumasi Edmund C. Merem +10 位作者 Zhu H. Ning Harriet B. Yeboah Priscilla M. Loh Jeff D. Osei Vanessa Ferchaud Matilda Anokye Esi Dadzie Dorcas T. Gyan Janeth E. Mjema Lucinda A. Kangwana Recheal N. D. Armah 《Agricultural Sciences》 2024年第11期1195-1222,共28页
While various prior studies have delved into the potential consequences of climate change on crop production in specific areas, notably in southeastern Louisiana, limited investigation has been carried out concerning ... While various prior studies have delved into the potential consequences of climate change on crop production in specific areas, notably in southeastern Louisiana, limited investigation has been carried out concerning some crops within the state of Louisiana. Consequently, there exists a dearth of knowledge regarding the specific hurdles and potential benefits confronting agricultural producers in this region. Therefore, the primary aim of this study was to explore and measure the impact of climate change on the yields of corn, rice, soybeans, and cotton in Louisiana, thereby addressing this informational void. The study uses data on average high temperatures and precipitation to assess the impact of climate change on these specific food crops in Louisiana. The researchers used ArcGIS and its symbology tool to create three separate maps depicting the spatial distribution of harvested cropland in Louisiana. The graduated color option was used on each map, which represented the years 2007, 2012, and 2017. Similarly, eight separate maps were created using the graduated color option to visually present the distribution patterns of Louisiana’s corn, cotton, rice, and soybean crops. These maps provided a visual representation of the state’s total crop production between 2007 and 2017. The researchers also created six bar charts to show the distribution of corn, cotton, rice, and soybean production in Louisiana over three time periods: 2007, 2012, and 2017. These charts also included information about the average high temperature and annual precipitation in each parish. The study revealed decreasing trends in Louisiana corn and cotton yields alongside consistent increases in rice and soybean yields, with projections suggesting future temperature rises may negatively impact crop yields, highlighting the need for research into climate-smart agricultural practices to mitigate these effects and safeguard global crop production. Louisiana’s response to climate change in food crop production involves implementing a comprehensive Climate-Resilient Agriculture Program, focusing on developing climate-adaptive crop varieties, sustainable water management, climate-responsive insurance, farmer education, and outreach to safeguard food security, enhance agricultural resilience, and ensure sustainable crop production. 展开更多
关键词 Climate Change CORN COTTON Precipitation SOYBEAN Temperature
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A Bibliometric Analysis Unveils Valuable Insights into the Past,Present,and Future Dynamics of Plant Acclimation to Temperature
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作者 Yong Cui Yongju Zhao +3 位作者 Shengnan Ouyang Changchang Shao Liangliang Li Honglang Duan 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期291-312,共22页
Plant temperature acclimation is closely related to maintaining a positive carbon gain under future climate change.However,no systematic summary of the field has been conducted.Based on this,we analyzed data on plant ... Plant temperature acclimation is closely related to maintaining a positive carbon gain under future climate change.However,no systematic summary of the field has been conducted.Based on this,we analyzed data on plant temperature acclimation from the Web of Science Core Collection database using bibliometric software R,RStudio and VOSviewer.Our study demonstrated that a stabilized upward trajectory was noted in publications(298 papers)from 1986 to 2011,followed by a swift growth(373 papers)from 2012 to 2022.The most impactful journals were Plant Cell and Environment,boasting the greatest count of worldwide citations and articles,the highest H-index and G-index,followed by Global Change Biology and New Phytologist,and Frontiers in Plant Science which had the highest M-index.The USA and China were identified as the most influential countries,while Atkin was the most influential author,and the Chinese Academy of Sciences was the most influential research institution.The most cited articles were published in the Annual Review of Plant Biology in 1999.“Cold acclimation”was the most prominent keyword.Future plant temperature acclimation research is expected to focus on thermal acclimation and photosynthesis,which have important significance for future agricultural production,forestry carbon sequestration,and global food security.In general,this study provides a systematic insight of the advancement,trend,and future of plant temperature acclimation research,enhancing the comprehension of how plants will deal with forthcoming climate change. 展开更多
关键词 TEMPERATURE ACCLIMATION plant responses climate change BIBLIOMETRIC
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Ecological Discourse Analysis Based on the Corpus-A Case Study on the Environmental Discourse of 21st Century
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作者 CHEN Yuang ZHI Yong-bi 《Journal of Literature and Art Studies》 2024年第8期693-702,共10页
Language learning materials not only provide language input for learners but also subtly disseminate ideology and influence readers’behavior.This study,based on the framework of ecological discourse analysis,quantita... Language learning materials not only provide language input for learners but also subtly disseminate ideology and influence readers’behavior.This study,based on the framework of ecological discourse analysis,quantitatively analyzes and qualitatively describes the ecological significance of environmental texts in the 21st Century.The aim is to provide references for the compilation of environmental discourse in language learning materials,promote the construction of more ecologically beneficial discourse,and facilitate the widespread dissemination of the ecological philosophy of“Diversity and Harmony,Interaction and Co-existence”among young readers.The initial findings of this study are as follows:In the environmental texts of the publication,a large number of relational processes and action processes are used to objectively represent the natural environment;the discourse tends to be ambiguous and beneficial,generally aligning with the ecological philosophy of“Diversity and Harmony,Interaction and Co-existence.”This can guide readers to correctly understand and face environmental issues,which is conducive to the healthy development of natural ecosystems. 展开更多
关键词 21st century ecological discourse analysis ecological orientation a corpus-based study
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Coping with the Impact of Climate Change: A Dive into Precision Agriculture in the United States
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作者 Oluwaseun Ibukun Kehinde Oke Olawale Oluwafemi 《Journal of Agricultural Chemistry and Environment》 2024年第2期208-222,共15页
With the continued increase in the number of people that are food insecure globally, which could be increasing because of the ongoing Ukraine-Russia war, leading to reduction in international agribusinesses, coupled w... With the continued increase in the number of people that are food insecure globally, which could be increasing because of the ongoing Ukraine-Russia war, leading to reduction in international agribusinesses, coupled with drastic climate change exacerbating the problem of food insecurity, there is a constant need to come up with innovative approaches to solve this global issue. In this article, we articulated how precision agriculture can be a tool for ensuring food security in the United States. This study aims to reiterate the significance of precision agriculture in solving global food insecurity. 展开更多
关键词 United States Food Insecurity Precision Agriculture Positioning Systems Climate Change
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Changing Characteristics of Comfort Index of Human Body in Bengbu City in the Past 40 Years under the Background of Climate Change
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作者 Lei SHAN Xian ZHANG +2 位作者 Lei TIAN Ranran HE Jingyang CHEN 《Meteorological and Environmental Research》 2024年第2期40-43,共4页
Based on the daily meteorological data of Bengbu City during 1981-2020,the changing characteristics of three elements needed for the calculation of the comfort index of human body(CIHB)were discussed,and daily CIHB wa... Based on the daily meteorological data of Bengbu City during 1981-2020,the changing characteristics of three elements needed for the calculation of the comfort index of human body(CIHB)were discussed,and daily CIHB was classified and discussed.The results show that from 1981 to 2020,annual average temperature tended to increase significantly.Annual average wind speed and relative humidity showed a decreasing trend before 2011 but an increasing trend after 2011.The duration of the four seasons in Bengbu City mainly rose in spring,reduced in winter,declined first and then increased in summer,and rose first and then decreased in autumn.As CIHB was at grades 1 and 9(the most uncomfortable),the three factors had different effects on them.For cold weather,the influence of relative humidity and wind speed on CIHB can not be ignored besides temperature.In hot weather,the influence of temperature was dominant,and the change of annual average temperature could well correspond to the change in the number of very hot days.In the context of climate warming,the number of cold days tended to decline generally,but it was larger in the years with fewer very cold days.Under the background of climate warming,there was no obvious change in the number of days of the overall comfort of human body.The number of hot days was closely related to the duration of summer,and the number of days of grade 8 rose significantly in the years with an increase in the duration of summer. 展开更多
关键词 Climate change Human comfort Comfort index of human body(CIHB)
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When History Becomes A Standing Joke:Mo Yan's Reflection on China's Historical Changes Throughout the 20th Century
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作者 ZHANG Yong YANG Fang 《Journal of Literature and Art Studies》 2017年第7期783-791,共9页
Since the end of the 20th century, Mo Yan has made an attempt to reflect on China's historical changes throughout the 20th century as a whole. Centered on such several novels as Big Breasts and Wide Hips, Life and De... Since the end of the 20th century, Mo Yan has made an attempt to reflect on China's historical changes throughout the 20th century as a whole. Centered on such several novels as Big Breasts and Wide Hips, Life and Death Are Wearing Me Out and Frog, this paper explores the author's thinking of the interruption and repetition phenomena in China's 20th century history. Differing from viewing the history in a modem linear progressive perspective, Mo Yan regards the interruption of history as a sign of human degradation, which derives from the loss of folk history subjectivity. When history is treated rudely, its repetition will occur, and the one who treats history as laughingstocks will be written into history as part of a "farce". 展开更多
关键词 Mo Yan the 20th century interruption of history repetition of history
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Changing Characteristic of Romantic Poetry in the 19th Century
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作者 Muhammad Qasim Bughio Shagufta Jabeen 《Sino-US English Teaching》 2011年第4期260-265,共6页
Change is the law of nature. Every writer enriches literature by coining new ideas. As Aristotle disagreed with Plato by saying that poetry is not blind but creative imitation, and emotions if remain pent up in mind, ... Change is the law of nature. Every writer enriches literature by coining new ideas. As Aristotle disagreed with Plato by saying that poetry is not blind but creative imitation, and emotions if remain pent up in mind, would erupt sooner or later like a volcano. Later on Classics have written poetry either to praise kings and queens, or to reform the society, but Romantics like Aristotle ushered against Classics and penned down writings bearing entirely different characteristics than earlier poetry with creative imagination. This paper is captivating study of the meanings and changing characteristics of romantic poetry during 19th century. Romanticism means having a visionary, imaginative or emotional appeal, to give emotions upper hand over reason. It was not a sudden movement, tends and tendencies were already there, which reached to its climax in hands of Blake, Wordsworth, Shelley, Keats and Byron, who awakened against Pope, Swift and Johnson. Romanticism has its origin in French revolution. The distinctive features of French revolution are freedom, brotherhood and equality. Romanticism was a revolt against the system through which they tried to change the status of common men. William Blake was foremost among romantics who believed that this vegetable world is, but only a shadow of the real world which is of imagination and attempted to convey the celestial message of love everywhere. In the poetry of Wordsworth and Coleridge, the naturalistic tendency remained more prominent, whereas Keats' and Shelley's poetry in a more specified sense was romantic marked by the emphasis on love of the supernatural, the marvelous and the exotic mythological world. Victorian poetry was not original like Romantics. Romantics introduced poetry bearing entirely different character than earlier poetry, with original ideas, whereas Victorian poets had written about social problems. Romantics were individualistically supreme in their ideas. Tennyson and Arnold took themes of their poetry from their surrounding, so no egoistic element was in the poetry of that century. Romantics introduced a change by plunging into imagination, whereas Victorians ended this trend by bringing readers into the world of realities, but there change was brought to provide momentarily relief and here its purpose was reformation. 展开更多
关键词 ROMANTICisM DEFINITION HisTORY changes
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Huu S. TIEU Request for FDA to Establish Regenerating Human Cells as Law on December 13, 2016 President Barack H. Obama Signed the 21st Century CURES Act into FDA Regulation and Law
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作者 Huu S. Tieu Martin F. Loeffler Edgar A. Ayala 《Open Journal of Regenerative Medicine》 CAS 2022年第3期55-62,共8页
Background and Aims: On November 24, 2009, Huu S. TIEU and Golden Sunrise Pharmaceutical, Inc. (Golden Sunrise) applied for the Technology and Innovation to be reviewed and evaluated by the U.S. Food and Drug Administ... Background and Aims: On November 24, 2009, Huu S. TIEU and Golden Sunrise Pharmaceutical, Inc. (Golden Sunrise) applied for the Technology and Innovation to be reviewed and evaluated by the U.S. Food and Drug Administration (FDA). In the review and evaluation, it was requested by Golden Sunrise designated the new indications for this application under Serious or Life-threatening conditions or diseases. Discussions followed with the FDA, Huu S. TIEU, and Golden Sunrise for FDA approval on new products and new indications on existing new Medical Technology and Innovation. It was agreed in Year-2015 that the FDA would take the request for new indications to the United States Congress to establish into FDA regulation and law. At that time the following was the FDA Guidance—“Emergency Use of a Test Article” is exempt from prior Institutional Review Board or Advisory Committee evaluation and approval, provided that such emergency use is reported to the Institutional Review Board within five working days after use. Expedited Institutional Review Board or Advisory Committee approval is not permitted in emergency use. There has been no funding to the authors for the writing or publication of this article. Methods: It was requested by Huu S. TIEU and Golden Sunrise in documents given to the FDA to have Serious or Life-threatening conditions or diseases indication be recognized by law. On August 08, 2015, the FDA responding to this request took the documentation produced by Golden Sunrise to the United States Congress on behalf of Golden Sunrise and Huu S. TIEU. This article encompasses the FDA regulatory method as well as the discussion and results of the establishment of the FDA and the 21<sup>st</sup> Century Cures Act. Results: On December 13, 2016, H.R.34—114<sup>th</sup> United States Congress (2015-2016) 21<sup>st</sup> Century CURES Act was signed into law by President Barack H. Obama which included the Serious or Life-threatening indication to be written into the CURES Act. In summary, the 21<sup>st</sup> Century Cures Act is a landmark piece of legislation that enjoyed broad bipartisan support in United States Congress. The main goals of the Act are impactful and should transform future cancer, neurologic, and precision medicine or drug research as well as aid individuals with mental health is intended to facilitate the prompt approval of new agents and devices, clinicians should be aware of the types of data behind an approval and take this into consideration when developing illnesses and opioid dependence. However, some of the wording within the CURES Act regarding the drug and device approval process may bring pause to health care providers including pharmacists. Although this wording and implementing care plans and counseling patients. The 21<sup>st</sup> Century Cures Act was incorporated into laws and regulations by the FDA under § 3072 of the Act grants the Commissioner of Food and Drugs the authority to appoint and set the annual rate of pay for outstanding and qualified candidates to scientific, technical, or professional positions that support the development, review, and regulation of medical products. 展开更多
关键词 Huu S. TIEU Request for FDA to Establish Regenerating Human Cells as Law on December 13 2016 President Barack H. Obama Signed the 21st century CURES Act into FDA Regulation and Law
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Prediction of Climate Change in the 21^(st) Century in Dalian Area under the Various Emission Scenarios 被引量:1
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作者 程相坤 任学慧 刘捷 《Meteorological and Environmental Research》 CAS 2010年第5期66-70,共5页
By using the simulative results of more than 20 climate system models which were provided by the fourth assessment report of the Intergovernmental Panel on Climate Change(IPCC),the climate change in Dalian area in the... By using the simulative results of more than 20 climate system models which were provided by the fourth assessment report of the Intergovernmental Panel on Climate Change(IPCC),the climate change in Dalian area in the 21st century under the different scenarios(SRES A2,SRES A1B and SRES B1) were analyzed and predicted with the multi-model's aggregative simulative results via the interpolation downscaling calculation.The results showed that the climate in Dalian would have the obvious warming and wetting tendency in the 21st century as a whole.The annual average warming tendency of air temperature would be 2.45-3.46 ℃/100 years,and the annual precipitation increase trend would be 5.8%-16.3% per 100 years.The warming in winter would be the most obvious,and the precipitation increase would be comparatively obvious in winter and spring.The precipitation decrease would be comparatively obvious in autumn in the previous period of 21st century.In A2,A1B and B1 scenarios,the air temperatures in the late period of 21st century would respectively be 3.46,3.44 and 2.45 ℃ higher than in the ordinary years,and the annual precipitation would respectively be 16.3%,11.8% and 5.79% more than in the ordinary years. 展开更多
关键词 Global climate model IPCC AR4 Climate change Surface temperature PRECIPITATION China
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The Status of English as a Lingua Franca in the 21st Century
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作者 李瑞凌 《海外英语》 2011年第14期350-351,共2页
The status of a language as a lingua franca in the 21st century is not determined by its linguistic merits,or the number of people who speak the language,or a country's language policy,but the combined effect of p... The status of a language as a lingua franca in the 21st century is not determined by its linguistic merits,or the number of people who speak the language,or a country's language policy,but the combined effect of political,economic and cultural forces.English as a future lingua franca has three characteristics:the status of official language in several countries;a priority in countries' foreign-language teaching programme;being widely used all over the world. 展开更多
关键词 ENGLisH STATUS lingua franca the 21st century
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An Explorative Research into the Factors Affecting Chinese Students' Retention and Application of English New Words
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作者 李淑媛 《Sino-US English Teaching》 2006年第4期19-22,26,共5页
Vocabulary has a direct impact on people's communication competence. A good mastery of an English word covers its pronunciation, spelling, part of speech, meaning and application. This article will focus only on fact... Vocabulary has a direct impact on people's communication competence. A good mastery of an English word covers its pronunciation, spelling, part of speech, meaning and application. This article will focus only on factors affecting the retention and application of a word from the perspective of semantic disparities, different defining angles in English and Chinese, emotional coloring and styles, morphological changes, and collocation. The author hopes that this article will be able to provide some insights into vocabulary teaching. 展开更多
关键词 semantic disparity emotional and coloring styles morphological changes COLLOCATION
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Plastid phylogenomics provides new insights into the systematics,diversification,and biogeography of Cymbidium(Orchidaceae) 被引量:2
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作者 Hai-Yao Chen Zhi-Rong Zhang +7 位作者 Xin Yao Ji-Dong Ya Xiao-Hua Jin Lin Wang Lu Lu De-Zhu Li Jun-Bo Yang Wen-Bin Yu 《Plant Diversity》 SCIE CAS CSCD 2024年第4期448-461,共14页
Cymbidium(Orchidaceae:Epidendroideae),with around 60 species,is widely-distributed across Southeast Asia,providing a nice system for studying the processes that underlie patterns of biodiversity in the region.However,... Cymbidium(Orchidaceae:Epidendroideae),with around 60 species,is widely-distributed across Southeast Asia,providing a nice system for studying the processes that underlie patterns of biodiversity in the region.However,phylogenetic relationships of Cymbidium have not been well resolved,hampering investigations of species diversification and the biogeographical history of this genus.In this study,we construct a plastome phylogeny of 56 Cymbidium species,with four well-resolved major clades,which provides a framework for biogeographical and diversification rate analyses.Molecular dating and biogeographical analyses show that Cymbidium likely originated in the region spanning northern IndoBurma to the eastern Himalayas during the early Miocene(~21.10 Ma).It then rapidly diversified into four major clades in East Asia within approximately a million years during the middle Miocene.Cymbidium spp.migration to the adjacent regions(Borneo,Philippines,and Sulawesi)primarily occurred during the Pliocene-Pleistocene period.Our analyses indicate that the net diversification rate of Cymbidium has decreased since its origin,and is positively associated with changes in temperature and monsoon intensity.Favorable hydrothermal conditions brought by monsoon intensification in the early Miocene possibly contributed to the initial rapid diversification,after which the net diversification rate was reduced with the cooling climate after the middle Miocene.The transition from epiphytic to terrestrial habits may have enabled adaptation to cooler environments and colonization of northern niches,yet without a significant effect on diversification rates.This study provides new insights into how monsoon activity and temperature changes affected the diversification dynamics of plants in Southeast Asia. 展开更多
关键词 CYMBIDIUM East Asia Asian monsoons Climate change Biogeographical patterns
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Arctic Sea Ice Variations in the First Half of the 20th Century:A New Reconstruction Based on Hydrometeorological Data 被引量:1
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作者 Vladimir A.SEMENOV Tatiana A.ALDONINA +2 位作者 Fei LI Noel Sebastian KEENLYSIDE Lin WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1483-1495,1686-1693,共21页
The shrinking Arctic sea-ice area(SIA) in recent decades is a striking manifestation of the ongoing climate change.Variations of the Arctic sea ice have been continuously observed by satellites since 1979, relatively ... The shrinking Arctic sea-ice area(SIA) in recent decades is a striking manifestation of the ongoing climate change.Variations of the Arctic sea ice have been continuously observed by satellites since 1979, relatively well monitored since the 1950s, but are highly uncertain in the earlier period due to a lack of observations. Several reconstructions of the historical gridded sea-ice concentration(SIC) data were recently presented based on synthesized regional sea-ice observations or by applying a hybrid model–empirical approach. Here, we present an SIC reconstruction for the period1901–2019 based on established co-variability between SIC and surface air temperature, sea surface temperature, and sea level pressure patterns. The reconstructed sea-ice data for March and September are compared to the frequently used Had ISST1.1 and SIBT1850 datasets. Our reconstruction shows a large decrease in SIA from the 1920 to 1940 concurrent with the Early 20th Century Warming event in the Arctic. Such a negative SIA anomaly is absent in Had ISST1.1 data. The amplitude of the SIA anomaly reaches about 0.8 mln km^(2) in March and 1.5 mln km^(2) in September. The anomaly is about three times stronger than that in the SIBT1850 dataset. The larger decrease in SIA in September is largely due to the stronger SIC reduction in the western sector of the Arctic Ocean in the 70°–80°N latitudinal zone. Our reconstruction provides gridded monthly data that can be used as boundary conditions for atmospheric reanalyses and model experiments to study the Arctic climate for the first half of the 20th century. 展开更多
关键词 Arctic sea ice Arctic climate early 20th century warming climate variability
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Global Change in Agricultural Flash Drought over the 21st Century 被引量:1
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作者 Emily BLACK 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期209-220,I0002-I0019,共30页
Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop... Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop cultivation. Increases in the frequency of these rare events in a future warmer climate would have significant societal impact. This study uses an ensemble of 10 Coupled Model Intercomparison Project(CMIP) models to investigate the projected change in agricultural flash drought during the 21st century. Comparison across geographical regions and climatic zones indicates that individual events are preceded by anomalously low relative humidity and precipitation, with long-term trends governed by changes in temperature, relative humidity, and soil moisture. As a result of these processes, the frequency of both upperlevel and root-zone flash drought is projected to more than double in the mid-and high latitudes over the 21st century, with hot spots developing in the temperate regions of Europe, and humid regions of South America, Europe, and southern Africa. 展开更多
关键词 flash drought climate change soil moisture agricultural drought CMIP
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Indian monsoon drove the dispersal of the thoracica group of Scytodes spitting spiders 被引量:1
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作者 Yu-Fa Luo Shu-Qiang Li 《Zoological Research》 SCIE CSCD 2024年第1期152-159,共8页
We examined the global biogeography of the Scytodes thoracica group of spitting spiders based on 23 years of sampling at the species level(61 species in the thoracica group and 84 species of Scytodes)using DNA data fr... We examined the global biogeography of the Scytodes thoracica group of spitting spiders based on 23 years of sampling at the species level(61 species in the thoracica group and 84 species of Scytodes)using DNA data from six loci.Our results indicated that the thoracica group initially dispersed from Southeast Asia to East Africa between 46.5 and 33.0 million years ago,and dispersal events intensified between Southeast/South Asia and East/South Africa from the early to late Miocene.The timing of these events indicates that Asian-African faunal exchange of the thoracica group was driven by the Indian monsoon,and the pattern of dispersal suggests that colonialization took root when the Indian monsoon shifted from a North-South direction to an East-West direction from the middle Eocene. 展开更多
关键词 Geological event Climate change Ballooning organism Faunal exchange Species distribution
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Climate change drives flooding risk increases in the Yellow River Basin 被引量:1
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作者 Hengxing Lan Zheng Zhao +9 位作者 Langping Li Junhua Li Bojie Fu Naiman Tian Ruixun Lai Sha Zhou Yanbo Zhu Fanyu Zhang Jianbing Peng John J.Clague 《Geography and Sustainability》 CSCD 2024年第2期193-199,共7页
The Yellow River Basin(YRB)has experienced severe floods and continuous riverbed elevation throughout history.Global climate change has been suggested to be driving a worldwide increase in flooding risk.However,owing ... The Yellow River Basin(YRB)has experienced severe floods and continuous riverbed elevation throughout history.Global climate change has been suggested to be driving a worldwide increase in flooding risk.However,owing to insufficient evidence,the quantitative correlation between flooding and climate change remains illdefined.We present a long time series of maximum flood discharge in the YRB dating back to 1843 compiled from historical documents and instrument measurements.Variations in yearly maximum flood discharge show distinct periods:a dramatic decreasing period from 1843 to 1950,and an oscillating gentle decreasing from 1950 to 2021,with the latter period also showing increasing more extreme floods.A Mann-Kendall test analysis suggests that the latter period can be further split into two distinct sub-periods:an oscillating gentle decreasing period from 1950 to 2000,and a clear recent increasing period from 2000 to 2021.We further predict that climate change will cause an ongoing remarkable increase in future flooding risk and an∼44.4 billion US dollars loss of floods in the YRB in 2100. 展开更多
关键词 Flooding risk Risk management Climate change Flood discharge Extreme precipitation
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Predicting potential invasion risks of Leucaena leucocephala(Lam.)de Wit in the arid area of Saudi Arabia 被引量:1
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作者 Haq S MARIFATUL Darwish MOHAMMED +3 位作者 Waheed MUHAMMAD Kumar MANOJ Siddiqui H MANZER Bussmann W RAINER 《Journal of Arid Land》 SCIE CSCD 2024年第7期983-999,共17页
The presence of invasive plant species poses a substantial ecological impact,thus comprehensive evaluation of their potential range and risk under the influence of climate change is necessary.This study uses maximum e... The presence of invasive plant species poses a substantial ecological impact,thus comprehensive evaluation of their potential range and risk under the influence of climate change is necessary.This study uses maximum entropy(MaxEnt)modeling to forecast the likelihood of Leucaena leucocephala(Lam.)de Wit invasion in Saudi Arabia under present and future climate change scenarios.Utilizing the MaxEnt modeling,we integrated climatic and soil data to predict habitat suitability for the invasive species.We conducted a detailed analysis of the distribution patterns of the species,using climate variables and ecological factors.We focused on the important influence of temperature seasonality,temperature annual range,and precipitation seasonality.The distribution modeling used robust measures of area under the curve(AUC)and receiver-operator characteristic(ROC)curves,to map the invasion extent,which has a high level of accuracy in identifying appropriate habitats.The complex interaction that influenced the invasion of L.leucocephala was highlighted by the environmental parameters using Jackknife test.Presently,the actual geographic area where L.leucocephala was found in Saudi Arabia was considerably smaller than the theoretical maximum range,suggesting that it had the capacity to expand further.The MaxEnt model exhibited excellent prediction accuracy and produced reliable results based on the data from the ROC curve.Precipitation and temperature were the primary factors influencing the potential distribution of L.leucocephala.Currently,an estimated area of 216,342 km^(2)in Saudi Arabia was at a high probability of invasion by L.leucocephala.We investigated the potential for increased invasion hazards in the future due to climate change scenarios(Shared Socioeconomic Pathways(SSPs)245 and 585).The analysis of key climatic variables,including temperature seasonality and annual range,along with soil properties such as clay composition and nitrogen content,unveiled their substantial influence on the distribution dynamic of L.leucocephala.Our findings indicated a significant expansion of high risk zones.High-risk zones for L.leucocephala invasion in the current climate conditions had notable expansions projected under future climate scenarios,particularly evident in southern Makkah,Al Bahah,Madina,and Asir areas.The results,backed by thorough spatial studies,emphasize the need to reduce the possible ecological impacts of climate change on the spread of L.leucocephala.Moreover,the study provides valuable strategic insights for the management of invasion,highlighting the intricate relationship between climate change,habitat appropriateness,and the risks associated with invasive species.Proactive techniques are suggested to avoid and manage the spread of L.leucocephala,considering its high potential for future spread.This study enhances the overall comprehension of the dynamics of invasive species by combining modeling techniques with ecological knowledge.It also provides valuable information for decision-making to implement efficient conservation and management strategies in response to changing environmental conditions. 展开更多
关键词 area under the curve invasive species invasion risks climate change MaxEnt model
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The Evolution of Organic Carbon in Chinese Mollisol Under Different Farming Systems: Validation and Prediction by Using Century Model 被引量:6
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作者 GAO Chong-sheng WANG Jian-guo ZHANG Xing-yi SUI Yue-yu 《Agricultural Sciences in China》 CAS CSCD 2008年第12期1490-1496,共7页
Soil organic carbon (SOC) is an important indicator of soil degradation process. In this study, the long-term SOC evolution in Chinese mollisol farmland was simulated and predicted by validating, analyzing, processi... Soil organic carbon (SOC) is an important indicator of soil degradation process. In this study, the long-term SOC evolution in Chinese mollisol farmland was simulated and predicted by validating, analyzing, processing and assorting concerning data, based on clarifying parameters of Century model need, combined with best use of recorded data of field management, observed data of long-term experiments, climate, soil, and biology, and achieved results from Hailun Agro-Ecological Experimental Station, Chinese Academy of Sciences. The results were showed as follows: Before reclamation, SOC content was around 58.00 g kg^-1, SOC content dropped quickly in early years, and then decreased slowly after reclamation. SOC content was around 34.00 g kg^-1 with a yearly average rate of 8.91‰ decrease before long-term experiments was established. After a long-term experiment, SOC would change under different farming systems. Shift farming system changed as follows: By 20-year model simulation, SOC content decreased from 34.03 to 30.19 g kg^-1, with a yearly average rate of 5.97‰; by 100-year model simulation, SOC content decreased to 24.31 g kg^-1, with a yearly average rate of 3.36‰. Organic farming system changed as follows: By 20-year model simulation, SOC content decreased slowly from 34.03 to 33.39 g kg^-1, with a yearly average rate of 0.95‰, 5‰ less than that of shift farming system; by 100-year model simulation, SOC content decreased to 32.21 g kg^-1, with a yearly average rate of 0.55‰. "Petroleum" farming system changed as follows: By 20-year model simulation, SOC content decreased from 34.03 to 32.88 g kg^-1, with a yearly average rate of 1.72‰, much more than that of organic farming system; by 100-year model simulation, SOC content decreased to 30.89 g kg^-1, with a yearly average rate of 0.96‰. Combined "petroleum"-organic farming system changed as follows: By 20-year model simulation, SOC content was increased slightly; by 100-year model simulation, SOC content increased from 34.03 to 34.41g kg^-1, with a yearly average rate of 0.11‰. The above results provided an optimal way for maintaining SOC in Chinese mollisol farmland: To increase, as much as possible within agro-ecosystem, soil organic matter returns such as crop stubble, crop litter, crop straw or stalk, and manure, besides applying chemical nitrogen and phosphorous, which increased system productivity and maintained SOC content as well. Also, the results provided a valuable methodology both for a study of CO2 sequestration capacity and for a target fertility determination in Chinese mollisol. 展开更多
关键词 century model Chinese mollisol farmland soil organic carbon various farming systems PREDICTION
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Recent Progress in Studies of the Variabilities and Mechanisms of the East Asian Monsoon in a Changing Climate 被引量:17
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作者 Wen CHEN Lin WANG +4 位作者 Juan FENG Zhiping WEN Tiaojiao MA Xiuqun YANG Chenghai WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第9期887-901,共15页
Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community... Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community and is particularly challenging in a changing climate where the global mean temperature has been rising.Recent advances in studies of the variabilities and mechanisms of the EAM are reviewed in this paper,focusing on the interannual to interdecadal time scales.Some new results have been achieved in understanding the behaviors of the EAM,such as the evolution of the East Asian summer monsoon(EASM),including both its onset and withdrawal over the South China Sea,the changes in the northern boundary activity of the EASM,or the transitional climate zone in East Asia,and the cycle of the EASM and the East Asian winter monsoon and their linkages.In addition,understanding of the mechanism of the EAM variability has improved in several aspects,including the impacts of different types of ENSO on the EAM,the impacts from the Indian Ocean and Atlantic Ocean,and the roles of mid-to high-latitude processes.Finally,some scientific issues regarding our understanding of the EAM are proposed for future investigation. 展开更多
关键词 EAST ASIAN summer MONSOON EAST ASIAN winter MONSOON changing CLIMATE MONSOON onset and withdrawal transitional CLIMATE zone different types of ENSO
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Role of Extratropical Cyclones in the Recently Observed Increase in Poleward Moisture Transport into the Arctic Ocean 被引量:3
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作者 Gian A.VILLAMIL-OTERO Jing ZHANG +1 位作者 ,Juanxiong HE Xiangdong ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第1期85-94,共10页
Poleward atmospheric moisture transport(AMT) into the Arctic Ocean can change atmospheric moisture or water vapor content and cause cloud formation and redistribution, which may change downward longwave radiation and,... Poleward atmospheric moisture transport(AMT) into the Arctic Ocean can change atmospheric moisture or water vapor content and cause cloud formation and redistribution, which may change downward longwave radiation and, in turn, surface energy budgets, air temperatures, and sea-ice production and melt. In this study, we found a consistently enhanced poleward AMT across 60?N since 1959 based on the NCAR–NCEP reanalysis. Regional analysis demonstrates that the poleward AMT predominantly occurs over the North Atlantic and North Pacific regions, contributing about 57% and 32%, respectively, to the total transport. To improve our understanding of the driving force for this enhanced poleward AMT, we explored the role that extratropical cyclone activity may play. Climatologically, about 207 extratropical cyclones move across 60?N into the Arctic Ocean each year, among which about 66(32% of the total) and 47(23%) originate from the North Atlantic and North Pacific Ocean, respectively. When analyzing the linear trends of the time series constructed by using a 20-year running window, we found a positive correlation of 0.70 between poleward yearly AMT and the integrated cyclone activity index(measurement of cyclone intensity, number, and duration). This shows the consistent multidecadal changes between these two parameters and may suggest cyclone activity plays a driving role in the enhanced poleward AMT. Furthermore, a composite analysis indicates that intensification and poleward extension of the Icelandic low and accompanying strengthened cyclone activity play an important role in enhancing poleward AMT over the North Atlantic region. 展开更多
关键词 atmospheric moisture transport cyclone activity atmospheric circulation ARCTIC climate change
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