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Direct-Seeded Rice: Genetic Improvement of Game-Changing Traits for Better Adaption
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作者 Priyanka NEGI Jagadish RANE +10 位作者 Rajendra Sadashiv WAGH Tukaram Jayaram BHOR Dipti Digambar GODSE Priyanka JADHAV C.ANILKUMAR Dasari SREEKANTH K.SAMMI REDDY Sharad Ramrao GADAKH K.M.BORAIH C.B.HARISHA P.S.BASAVARAJ 《Rice science》 SCIE CSCD 2024年第4期417-433,共17页
The sustainability of rice production continues to be a subject of uncertainty and inquiry attributed to shifts in climatic conditions. In light of the impending climate change crisis and the high labor and water cost... The sustainability of rice production continues to be a subject of uncertainty and inquiry attributed to shifts in climatic conditions. In light of the impending climate change crisis and the high labor and water costs accompanying it, direct-seeded rice(DSR) is unquestionably one of the most practical solutions. Despite its resource and climate-friendly advantages, early maturing rice faces weed competitiveness and seedling establishment challenges. Resolving these issues is crucial for promoting its wider adoption among farmers, presenting it as a more effective sustainable rice cultivation method globally. Diverse traditional and contemporary breeding methods are employed to mitigate the limitations of the DSR approach, leveraging advanced techniques such as speed breeding and genome editing. Focusing on key traits like mesocotyl length elongation, early seedling vigor, root system architecture, and weed competitiveness holds promise for transformative improvements in DSR adaptation at a broader scale within farming communities. This review aims to summarize how these features contribute to increased crop production in DSR conditions and explore the research efforts focusing on enhancing DSR adaptation through these traits. Emphasizing the pivotal role of these game-changing traits in DSR adaptation, our analysis sheds light on their potential transformative impact and offers valuable insights for advancing DSR practices. 展开更多
关键词 climate change direct-seeded rice aerobic rice early vigor trait
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China and the Changing Global Economic Order
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作者 WARWICK POWELL 《China Today》 2024年第9期40-43,共4页
A better understanding of China’s modernization presents an insight into a changing world.AS China has developed,so too has the global economy.For the past 200 years or so,the structure of the global economy was domi... A better understanding of China’s modernization presents an insight into a changing world.AS China has developed,so too has the global economy.For the past 200 years or so,the structure of the global economy was dominated first by the British empire,and more recently by the U.S.as the global economic hegemon.This system of center-and-peripheries is now decentering,with a diversification of networks and connections creating a multinodal system of value growth and circulation. 展开更多
关键词 changing creating MODERNIZATION
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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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Existence of Monotone Positive Solution for a Fourth-Order Three-Point BVP with Sign-Changing Green’s Function
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作者 Junrui Yue Yun Zhang Qingyue Bai 《Open Journal of Applied Sciences》 2024年第1期63-69,共7页
This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones a... This paper is concerned with the following fourth-order three-point boundary value problem , where , we discuss the existence of positive solutions to the above problem by applying to the fixed point theory in cones and iterative technique. 展开更多
关键词 Fourth-Order Three-Point Boundary Value Problem Sign-changing Green’s Function Fixed Point Index Iterative Technique Monotone Positive Solution EXISTENCE
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How Himalayan communities are changing cultivation practices in the context of climate change 被引量:1
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作者 Ashma SUBEDI Nani RAUT Smriti GURUNG 《Regional Sustainability》 2023年第4期378-389,共12页
Climate change can have significant impacts on crop yields and food security.This study assessed the linkages between climate change and crop yields to obtain a better understanding on the drivers of food security.The... Climate change can have significant impacts on crop yields and food security.This study assessed the linkages between climate change and crop yields to obtain a better understanding on the drivers of food security.The study was conducted in Pasagaun village of Lamjung District in Nepal,where household surveys and focus group discussions(FGDs)were used to collect data including crop cultivation,irrigation facilities,and adaptation strategies.Moreover,climate data(temperature and precipitation)from 1992 to 2020 were collected from the Khudi Bazar meteorological station and crop yield data were obtained from the Agri-Business Promotion and Statistics Division.Trend analysis of temperature and precipitation was conducted using MannKendall trend test and Sen’s slope method,and the results showed an increase in the average temperature of approximately 0.02℃/a and a decrease in the annual precipitation of 9.84 mm/a.The cultivation of traditional varieties of rice and foxtail millet(Kaguno)has vanished.Although,there was no significant impact of the maximum temperature on the yield of rice and maize,the regression analysis revealed that there are negative relationships between rice yield and annual minimum temperature(r=-0.44),between millet yield and annual precipitation(r=-0.30),and between maize yield and annual minimum temperature(r=-0.31),as well as positive relationship between rice yield and annual precipitation(r=0.16).Moreover,average rice yield and millet yield have decreased by 27.0% and 57.0% in 2000-2020,respectively.Despite other reasons for the decrease in crop yield such as the lack of irrigation facilities,out-migration of farmer,and increased pest infestation,respondents have adopted adaptation strategies(for example,shifts in cultivation time and changes in crop types)to minimize the impacts of climate change.More investigation and community-based farming education are needed to understand and alleviate the harmful impacts of climate change on crop yield,as effective adaptation coping strategies are still insufficient.This study provides insights into the adaptation strategies that are necessary to keep food security in the face of climate change. 展开更多
关键词 Climate change Crop yield Adaptation strategies Farming practices Food security Nepal
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Characteristics and utility of combined duplex color-coded ultrasonography in the cervical rotational position with head MRI and MRA in the differential diagnosis of apogeotropic direction-changing positional nystagmus 被引量:1
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作者 Tessei Kuruma Mariko Arimoto Yasushi Fujimoto 《Journal of Otology》 CSCD 2023年第2期85-90,共6页
Objective:To determine whether cervical ultrasonography,magnetic resonance imaging(MRI),and magnetic resonance angiography(MRA)are useful in the differential diagnosis of etiology and understanding the pathophysiology... Objective:To determine whether cervical ultrasonography,magnetic resonance imaging(MRI),and magnetic resonance angiography(MRA)are useful in the differential diagnosis of etiology and understanding the pathophysiology in cases of apogeotropic direction-changing positional nystagmus(DCPN).Methods:Thirty patients with apogeotropic DCPN were classified into 11 cases of central disease,seven cases of mixed central and peripheral disease,and 12 cases of peripheral disease by differential diagnosis based on various balance function,neuro-otological,and imaging tests.Cervical ultrasonography using the cervical rotation method and MRI and MRA of the head and neck were performed in most patients with apogeotropic DCPN.We reviewed the presence of abnormal imaging findings according to the disease etiology.Results:Of the 30 patients with apogeotropic DCPN,23 showed vascular abnormalities or central lesions on imaging.Vascular lesions were found in six of the 12 patients with peripheral disease.Cervical ultrasonography with cervical rotation detected blood flow disturbance in the vertebral artery in eight patients in whom the disturbance could not be detected by MRI or MRA of the head and neck.Discussion:We hypothesize that the causative disease of apogeotropic DCPN may be strongly associated with circulatory insufficiency of the vertebrobasilar and carotid arteries,and that impaired blood flow in these vessels may affect peripheral vestibular and central function.In patients with apogeotropic DCPN,examinations of vestibular function,central nervous system symptoms,and brain hemodynamics are valuable for differential diagnosis. 展开更多
关键词 Apogeotropic direction changing positional NYSTAGMUS Vertebrobasilar artery Vertebrobasilar insufficiency(VBI) ULTRASONOGRAPHY MRI MRA
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基于统计损伤修正的冻结砂—黏混合土改进Duncan-Chang模型
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作者 滕振超 李正巍 +7 位作者 刘佳琳 周亚东 李波 刘彦峰 池林林 张圣童 刘博 计静 《东北石油大学学报》 CAS 北大核心 2024年第2期116-124,I0008,共10页
为描述冻结砂—黏混合土的偏应力—应变关系,进行不同含砂量冻结砂—黏混合土的冻土三轴压缩试验。基于改进的Duncan-Chang模型(D-C模型),引入统计损伤理论,拟合三轴压缩试验结果,分别建立以Mises强度准则和应变发展为微元强度变量的统... 为描述冻结砂—黏混合土的偏应力—应变关系,进行不同含砂量冻结砂—黏混合土的冻土三轴压缩试验。基于改进的Duncan-Chang模型(D-C模型),引入统计损伤理论,拟合三轴压缩试验结果,分别建立以Mises强度准则和应变发展为微元强度变量的统计损伤修正模型,对比计算结果与试验数据。结果表明:冻结砂—黏混合土偏应力峰值随含砂量的增加而增加,偏应力—应变曲线由应变硬化型逐渐过渡到应变软化型的临界含砂量为50%。当含砂量介于20%~60%时,基于统计损伤理论的修正改进D-C模型能有效拟合应变硬化型曲线和具有轻微应变软化现象的偏应力—应变曲线。当含砂量为90%时,基于应变发展的统计损伤修正模型的偏应力峰值与试验结果相差3%,具有较强适用性。该结果为不同微元强度变量的统计损伤修正模型提供参考。 展开更多
关键词 冻结砂—黏混合土 三轴压缩试验 改进Duncan-chang模型 统计损伤理论 应变软化模型
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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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Shikimic acid accelerates phase change and flowering in Chinese jujube 被引量:1
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作者 Xianwei Meng Zhiguo Liu +11 位作者 Li Dai Weiqiang Zhao Jiurui Wang Lili Wang Yuanpei Cui Ying Li Yinshan Cui Yao Zhang Luyao Wang Fengjiao Yu Jin Zhao Mengjun Liu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期413-424,共12页
The juvenile-to-adult phase change with first flowering as the indicator plays a crucial role in the lifecycle of fruit trees. However, the molecular mechanisms underlying phase change in fruit trees remain largely un... The juvenile-to-adult phase change with first flowering as the indicator plays a crucial role in the lifecycle of fruit trees. However, the molecular mechanisms underlying phase change in fruit trees remain largely unknown. Shikimic acid (ShA) pathway is a main metabolic pathway closely related to the synthesis of hormones and many important secondary metabolites participating in plant phase change. So,whether ShA regulates phase change in plants is worth clarifying. Here, the distinct morphological characteristics and the underlying mechanisms of phase change in jujube (Ziziphus jujuba Mill.), an important fruit tree native to China with nutritious fruit and outstanding tolerance abiotic stresses, were clarified. A combined transcriptome and metabolome analysis found that ShA is positively involved in jujube(Yuhong’×Xing 16’) phase change. The genes in the upstream of ShA synthesis pathway (ZjDAHPS, ZjDHQS and ZjSDH), the contents of ShA and the downstream secondary metabolites like phenols were significantly upregulated in the phase change period. Further, the treatment of spraying exogenous ShA verified that ShA at a very low concentration (60 mg·L^(-1)) can substantially speed up the phase change and flowering of jujube and other tested plants including Arabidopsis, tomato and wheat. The exogenous ShA (60 mg·L^(-1)) treatment in jujube seedlings could increase the accumulation of endogenous ShA, enhance leaf photosynthesis and the synthesis of phenols especially flavonoids and phenolic acids, and promote the expression of genes (ZjCOs, ZjNFYs and ZjPHYs) involved in flowering pathway. Basing on above results, we put forward a propose for the underlying mechanism of ShA regulating phase change, and a hypothesis that ShA could be considered a phytohormone-like substance because it is endogenous, ubiquitous, movable and highly efficient at very low concentrations. This study highlights the critical role of ShA in plant phase change and its phytohormone-like properties. 展开更多
关键词 Ziziphus jujuba Mill. Phase change FLOWERING Shikimic acid TRANSCRIPTOME METABOLOME
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Projected changes in extreme snowfall events over the Tibetan Plateau based on a set of RCM simulations 被引量:1
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作者 Yuanhai Fu Xuejie Gao 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期3-9,共7页
Extreme snowfall events over the Tibetan Plateau(TP)cause considerable damage to local society and natural ecosystems.In this study,the authors investigate the projected changes in such events over the TP and its surr... Extreme snowfall events over the Tibetan Plateau(TP)cause considerable damage to local society and natural ecosystems.In this study,the authors investigate the projected changes in such events over the TP and its surrounding areas based on an ensemble of a set of 21st century climate change projections using a regional climate model,RegCM4.The model is driven by five CMIP5 global climate models at a grid spacing of 25 km,under the RCP4.5 and RCP8.5 pathways.Four modified ETCCDI extreme indices-namely,SNOWTOT,S1mm,S10mm,and Sx5day-are employed to characterize the extreme snowfall events.RegCM4 generally reproduces the spatial distribution of the indices over the region,although with a tendency of overestimation.For the projected changes,a general decrease in SNOWTOT is found over most of the TP,with greater magnitude and better cross-simulation agreement over the eastern part.All the simulations project an overall decrease in S1mm,ranging from a 25%decrease in the west and to a 50%decrease in the east of the TP.Both S10mm and Sx5day are projected to decrease over the eastern part and increase over the central and western parts of the TP.Notably,S10mm shows a marked increase(more than double)with high cross-simulation agreement over the central TP.Significant increases in all four indices are found over the Tarim and Qaidam basins,and northwestern China north of the TP.The projected changes show topographic dependence over the TP in the latitudinal direction,and tend to decrease/increase in low-/high-altitude areas. 展开更多
关键词 Extreme snowfall Regional climate model Tibetan plateau Climate change
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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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Self‑Assembly of Binderless MXene Aerogel for Multiple‑Scenario and Responsive Phase Change Composites with Ultrahigh Thermal Energy Storage Density and Exceptional Electromagnetic Interference Shielding 被引量:1
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作者 Chuanbiao Zhu Yurong Hao +8 位作者 Hao Wu Mengni Chen Bingqing Quan Shuang Liu Xinpeng Hu Shilong Liu Qinghong Ji Xiang Lu Jinping Qu 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期367-382,共16页
The severe dependence of traditional phase change materials(PCMs)on the temperature-response and lattice deficiencies in versatility cannot satisfy demand for using such materials in complex application scenarios.Here... The severe dependence of traditional phase change materials(PCMs)on the temperature-response and lattice deficiencies in versatility cannot satisfy demand for using such materials in complex application scenarios.Here,we introduced metal ions to induce the self-assembly of MXene nanosheets and achieve their ordered arrangement by combining suction filtration and rapid freezing.Subsequently,a series of MXene/K^(+)/paraffin wax(PW)phase change composites(PCCs)were obtained via vacuum impregnation in molten PW.The prepared MXene-based PCCs showed versatile applications from macroscale technologies,successfully transforming solar,electric,and magnetic energy into thermal energy stored as latent heat in the PCCs.Moreover,due to the absence of binder in the MXene-based aerogel,MK3@PW exhibits a prime solar-thermal conversion efficiency(98.4%).Notably,MK3@PW can further convert the collected heat energy into electric energy through thermoelectric equipment and realize favorable solar-thermal-electric conversion(producing 206 mV of voltage with light radiation intensity of 200 mw cm^(−2)).An excellent Joule heat performance(reaching 105℃with an input voltage of 2.5 V)and responsive magnetic-thermal conversion behavior(a charging time of 11.8 s can achieve a thermal insulation effect of 285 s)for contactless thermotherapy were also demonstrated by the MK3@PW.Specifically,as a result of the ordered arrangement of MXene nanosheet self-assembly induced by potassium ions,MK3@PW PCC exhibits a higher electromagnetic shielding efficiency value(57.7 dB)than pure MXene aerogel/PW PCC(29.8 dB)with the same MXene mass.This work presents an opportunity for the multi-scene response and practical application of PCMs that satisfy demand of next-generation multifunctional PCCs. 展开更多
关键词 Self-assembly Multiple-scenario Phase change composites Thermal energy storage Electromagnetic interference shielding
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The Risk of Flooding to Architecture and Infrastructure amidst a Changing Climate in Lake Baringo, Kenya
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作者 Nyakundi Victor Plal Eric Kandu Kyeba 《American Journal of Climate Change》 2023年第1期80-99,共20页
Climate change has grown more apparent in recent years with people becoming more aware of its potentially disastrous consequences. Flooding is one of the many consequences of a changing climate in Kenya known to cause... Climate change has grown more apparent in recent years with people becoming more aware of its potentially disastrous consequences. Flooding is one of the many consequences of a changing climate in Kenya known to cause immense devastation resulting in the loss of lives and property. This paper discusses the risk of flooding in Kenya as one of the many outcomes of climate change in the face of urgency to adapt Kenya’s built environment to flooding which is likely to continue to prevail in the decades as a result of the looming climate change. It also sought to evaluate the physical, traumatic, and psychological effects on communities affected by flood events. This cross-sectional survey, both qualitative and quantitative in nature, executed between 13<sup>th</sup> January 2021 and 14<sup>th</sup> July 2021 with 132 respondents along the western shoreline of Lake Baringo, near Marigat Town focused on the flood levels, structures, their materials, and quantities. Results show that the area covered by Lake Baringo increased by 18% from 236 km<sup>2</sup> to 278 km<sup>2</sup>. The depth of floods ranged from 0.3 m to 1.2 m and exceeded 1.6 m during heavy rainfall up to 3.2 m with homes completely submerged by the lake. Flooding was experienced more by residents living in low areas nearer to the shoreline of the lake as compared to those living on higher grounds. 100% of the structures didn’t have the architectural technology to withstand the impacts of flooding with 59% of housing made of corrugated iron sheets both on wall and roofing, 22% of mud houses roofed with either corrugated iron sheets, 10% being timber with thatch and only 8% stoned walled houses. This predisposed all the residents to the harmful impacts of flooding. Piled sandbags by locals as a mitigating measure proved inadequate to withstand the forces of the rising waters. Flood walls were built around local lodges near the lake but the rising water level quickly breached these defences. The study recommends that county and national governing authorities develop flood adaptation strategies for resilience. These include long-term land-use planning, the establishment of early warning systems, evacuation plans, identification of vulnerable or high-risk populations, measures to ensure water quality, sanitation, and hygiene. Flood-resilient architecture including stilt and floating houses that mechanically rise and fall with respect to the highest water mark are recommended during flood events. Bridges on swollen rivers and resilient construction materials like reinforced concrete are to be used for sustainable development for flood risk adaptation. 展开更多
关键词 Architecture Climate change FLOODING RISK Lake Baringo
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Nitrogen Dioxide, Carbon Monoxide, Natural and Anthropomorphic Effects, and Earth’s Changing Climate
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作者 Shreyas Banaji 《Atmospheric and Climate Sciences》 CAS 2023年第1期62-71,共10页
This study will both compare and contrast the characteristics and roles of two pollutants: nitrogen dioxide and carbon monoxide. It will begin by tracing each gas’ negative contributions to the Earth’s spheres, as w... This study will both compare and contrast the characteristics and roles of two pollutants: nitrogen dioxide and carbon monoxide. It will begin by tracing each gas’ negative contributions to the Earth’s spheres, as well as relate any negative links that each plays concerning human activity, health, and interaction with the environment. It will include an in-depth analysis of what the proliferation of such toxic gases indicates about human production and causality, plus reflect on any current attempts being made to improve the effects of these pollutants on the environment. This examination will also inspect three NASA missions, i.e., MOPITT/Terra, AIRS/Aqua, and OMI/Aura, the aim of which, among many other tasks, is to detect pollutants within the Earth’s various spheres, as well as analyze weather anomalies, improve prediction methodology, and chronicle meteorological patterns for future study. It will also cover some of the goals, engineering breakthroughs, and in one case, the limitations, of these three satellite missions. Finally, it should be noted that in all stages of this discussion, the author’s main aim will be to focus on the positives that need to be implemented in order to improve the current situations that both anthropogenic and natural disasters have created for the planet. 展开更多
关键词 Carbon Monoxide Nitrogen Dioxide Climate change ATMOSPHERE Greenhouse Gases
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Assessment of first-order-moment-based sample reconstruction method for design flood estimation in changing environment
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作者 Yi-ming Hu Zhong-min Liang +2 位作者 Yi-xin Huang Jun Wang Bin-quan Li 《Water Science and Engineering》 EI CAS CSCD 2023年第3期226-233,共8页
Estimating the design flood under nonstationary conditions is challenging. In this study, a sample reconstruction approach was developed to transform a nonstationary series into a stationary one in a future time windo... Estimating the design flood under nonstationary conditions is challenging. In this study, a sample reconstruction approach was developed to transform a nonstationary series into a stationary one in a future time window (FTW). In this approach, the first-order moment (EFTW) of an extreme flood series in the FTW was used, and two possible methods of estimating EFTW values in terms of point values and confidence intervals were developed. Three schemes were proposed to analyze the uncertainty of design flood estimation in terms of sample representativeness, uncertainty from EFTW estimation, and both factors, respectively. To investigate the performance of the sample reconstruction approach, synthesis experiments were designed based on the annual peak series of the Little Sugar Creek in the United States. The results showed that the sample reconstruction approach performed well when the high-order moment of the series did not change significantly in the specified FTW. Otherwise, its performance deteriorated. In addition, the uncertainty of design flood estimation caused by sample representativeness was greater than that caused by EFTW estimation. 展开更多
关键词 Hydrological frequency analysis Nonstationarity Series reconstruction Uncertainty assessment changing environment
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A study on the simulation of carbon and water fluxes of Dangxiong alpine meadow and its response to climate change 被引量:1
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作者 Lingyun He Lei Zhong +3 位作者 Yaoming Ma Yuting Qi Jie Liu Peizhen Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期22-27,共6页
The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of th... The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation types.The Dangxiong alpine meadow ecosystem,located in the south-central part of the Tibetan Plateau,is a typical example.To understand the carbon and water fluxes,water use efficiency(WUE),and their responses to future climate change for the alpine meadow ecosystem in the Dangxiong area,two parameter estimation methods,the Model-independent Parameter Estimation(PEST)and the Dynamic Dimensions Search(DDS),were used to optimize the Biome-BGC model.Then,the gross primary productivity(GPP)and evapotranspiration(ET)were simulated.The results show that the DDS parameter calibration method has a better performance.The annual GPP and ET show an increasing trend,while the WUE shows a decreasing trend.Meanwhile,ET and GPP reach their peaks in July and August,respectively,and WUE shows a“dual-peak”pattern,reaching peaks in May and November.Furthermore,according to the simulation results for the next nearly 100 years,the ensemble average GPP and ET exhibit a significant increasing trend,and the growth rate under the SSP5–8.5 scenario is greater than that under the SSP2–4.5 scenario.WUE shows an increasing trend under the SSP2–4.5 scenario and a significant increasing trend under the SSP5–8.5 scenario.This study has important scientific significance for carbon and water cycle prediction and vegetation ecological protection on the Tibetan Plateau. 展开更多
关键词 Carbon and water flux Water use efficiency Alpine meadow Biome-BGC model Climate change
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Heat transfer enhanced inorganic phase change material compositing carbon nanotubes for battery thermal management and thermal runaway propagation mitigation 被引量:1
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作者 Xinyi Dai Ping Ping +4 位作者 Depeng Kong Xinzeng Gao Yue Zhang Gongquan Wang Rongqi Peng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期226-238,I0006,共14页
Developing technologies that can be applied simultaneously in battery thermal management(BTM)and thermal runaway(TR)mitigation is significant to improving the safety of lithium-ion battery systems.Inorganic phase chan... Developing technologies that can be applied simultaneously in battery thermal management(BTM)and thermal runaway(TR)mitigation is significant to improving the safety of lithium-ion battery systems.Inorganic phase change material(PCM)with nonflammability has the potential to achieve this dual function.This study proposed an encapsulated inorganic phase change material(EPCM)with a heat transfer enhancement for battery systems,where Na_(2)HPO_(4)·12H_(2)O was used as the core PCM encapsulated by silica and the additive of carbon nanotube(CNT)was applied to enhance the thermal conductivity.The microstructure and thermal properties of the EPCM/CNT were analyzed by a series of characterization tests.Two different incorporating methods of CNT were compared and the proper CNT adding amount was also studied.After preparation,the battery thermal management performance and TR propagation mitigation effects of EPCM/CNT were further investigated on the battery modules.The experimental results of thermal management tests showed that EPCM/CNT not only slowed down the temperature rising of the module but also improved the temperature uniformity during normal operation.The peak battery temperature decreased from 76℃to 61.2℃at 2 C discharge rate and the temperature difference was controlled below 3℃.Moreover,the results of TR propagation tests demonstrated that nonflammable EPCM/CNT with good heat absorption could work as a TR barrier,which exhibited effective mitigation on TR and TR propagation.The trigger time of three cells was successfully delayed by 129,474 and 551 s,respectively and the propagation intervals were greatly extended as well. 展开更多
关键词 Inorganic phase change material Carbon nanotube Battery thermal management Thermal runaway propagation Fire resistance ENCAPSULATION
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Prevalence of vegetation browning in China’s drylands under climate change 被引量:1
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作者 Li Fu Guolong Zhang +3 位作者 Jianping Huang Ming Peng Lei Ding Dongliang Han 《Geography and Sustainability》 CSCD 2024年第3期405-414,共10页
Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning ... Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning of vegetation remain scarce.In this study,we utilized the normalized difference vegetation index(NDVI)as an indicator of vegetation to investigate the trends of vegetation greening and browning(monotonic,interruption,and reversal)through the breaks for the additive season and trend(BFAST)method across China’s drylands from 1982 to 2022.It also reveals the impacts of ecological restoration programs(ERPs)and climate change on these vegetation trends.We find that the vegetation displays an obvious pattern of east-greening and west-browning in China’s drylands.Greening trends mainly exhibits monotonic greening(29.8%)and greening with setback(36.8%),whereas browning shows a greening to browning reversal(19.2%).The increase rate of greening to browning reversal is 0.0342/yr,which is apparently greater than that of greening with setback,0.0078/yr.This research highlights that,under the background of widespread vegetation greening,vegetation browning is pro-gressively increasing due to the effects of climate change.Furthermore,the ERPs have significantly increased vegetation coverage,with the increase rate in 2000-2022 being twice as much as that of 1982-1999 in reveg-etation regions.Vegetation browning in southwestern Qingzang Plateau is primarily driven by adverse climatic factors and anthropogenic disturbances,which offset the efforts of ERPs. 展开更多
关键词 China’s drylands Ecological restoration programs Climate change Greening to browning reversal BFAST
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Spatiotemporal changes of gross primary productivity and its response to drought in the Mongolian Plateau under climate change 被引量:1
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作者 ZHAO Xuqin LUO Min +3 位作者 MENG Fanhao SA Chula BAO Shanhu BAO Yuhai 《Journal of Arid Land》 SCIE CSCD 2024年第1期46-70,共25页
Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation... Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas. 展开更多
关键词 gross primary productivity(GPP) climate change warming aridification areas drought sensitivity cumulative effect duration(CED) Mongolian Plateau
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Characteristics and control factors of feldspar dissolution in gravity flow sandstone of Chang 7 Member,Triassic Yanchang Formation,Ordos Basin,NW China 被引量:1
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作者 ZHU Haihua ZHANG Qiuxia +4 位作者 DONG Guodong SHANG Fei ZHANG Fuyuan ZHAO Xiaoming ZHANG Xi 《Petroleum Exploration and Development》 SCIE 2024年第1期114-126,共13页
To clarify the formation and distribution of feldspar dissolution pores and predict the distribution of high-quality reservoir in gravity flow sandstone of the 7^(th) member of Triassic Yanchang Formation(Chang 7 Memb... To clarify the formation and distribution of feldspar dissolution pores and predict the distribution of high-quality reservoir in gravity flow sandstone of the 7^(th) member of Triassic Yanchang Formation(Chang 7 Member)in the Ordos Basin,thin sections,scanning electron microscopy,energy spectrum analysis,X-ray diffraction whole rock analysis,and dissolution experiments are employed in this study to investigate the characteristics and control factors of feldspar dissolution pores.The results show that:(1)Three types of diagenetic processes are observed in the feldspar of Chang 7 sandstone in the study area:secondary overgrowth of feldspar,replacement by clay and calcite,and dissolution of detrital feldspar.(2)The feldspar dissolution of Chang 7 tight sandstone is caused by organic acid,and is further affected by the type of feldspar,the degree of early feldspar alteration,and the buffering effect of mica debris on organic acid.(3)Feldspars have varying degrees of dissolution.Potassium feldspar is more susceptible to dissolution than plagioclase.Among potassium feldspar,orthoclase is more soluble than microcline,and unaltered feldspar is more soluble than early kaolinized or sericitized feldspar.(4)The dissolution experiment demonstrated that the presence of mica can hinder the dissolution of feldspar.Mica of the same mass has a significantly stronger capacity to consume organic acids than feldspar.(5)Dissolution pores in feldspar of Chang 7 Member are more abundant in areas with low mica content,and they improve the reservoir physical properties,while in areas with high mica content,the number of feldspar dissolution pores decreases significantly. 展开更多
关键词 gravity flow sandstone differential feldspar dissolution mica-feldspar dissolution experiment chang 7 Member of Triassic Yanchang Formation Ordos Basin
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