To probe the processes and mechanisms of soil organic carbon (SOC) changes during forest recovery, a 150-yearchronosequence study on SOC was conducted for various vegetation succession stages at the Ziwuling area, in ...To probe the processes and mechanisms of soil organic carbon (SOC) changes during forest recovery, a 150-yearchronosequence study on SOC was conducted for various vegetation succession stages at the Ziwuling area, in the centralpart of the Loess Plateau, China. Results showed that during the 150 years of local vegetation rehabilitation SOC increasedsignificantly (P < 0.05) over time in the initial period of 55-59 years, but slightly decreased afterwards. Average SOCdensities for the 0-100 cm layer of farmland, grassland, shrubland and forest were 4.46, 5.05, 9.95, and 7.49 kg C m-3,respectively. The decrease in SOC from 60 to 150 years of abandonment implied that the soil carbon pool was a sink forCO2 before the shrubland stage and became a source in the later period. This change resulted from the spatially variedcomposition and structure of the vegetation. Vegetation recovery had a maximum effect on the surface (0-20 cm) SOCpool. It. was concluded that vegetation recovery on the Loess Plateau could result in significantly increased sequestrationof atmospheric CO2 in soil and vegetation, which was ecologically important for mitigating the increase of atmosphericconcentration of CO2 and for ameliorating the local eco-environment.展开更多
Integrating remote sensing, geographic information system (GIS) and fractal theory, change characteristics of tidal flats and tidal creeks in the Huanghe (Yellow) River Delta over the period of 1986-2001 were discusse...Integrating remote sensing, geographic information system (GIS) and fractal theory, change characteristics of tidal flats and tidal creeks in the Huanghe (Yellow) River Delta over the period of 1986-2001 were discussed. The results show that evolutions of tidal flats throughout the Huanghe River Delta are influenced by various factors, and that progressive succession and regression of tidal flats concur in different coastal segments of the delta. Human activities have played an increasingly important role in the succession process of tidal flats. Due to land reclamation in coastal zones of the delta in the last 15 years, lots of tidal flats were occupied, the artificial coastline migrated seaward (the maximum change rate was 0.8 kmyr-1) and tidal creeks became sparser (the highest decreasing rate of length of tidal creeks was 14.9 kmyr-1). Except for two coastal segments from the Tiaohe Estuary to the 106 Station and from the south of the Huanghe River mouth to the north of the Xiaodao River Estuary, fractal dimension values of tidal creeks in the remaining coastal segments of the delta decreased. In addition, the time dimension, sediment fluxes into the sea, waves and tidal-currents have profound influences on the evolution process of tidal flats. Four types of tidal flats-river-dominated tidal flats, tide-dominated tidal flats, wave-dominated tidal flats and man-dominated tidal flats can be identified. Owing to the intensification of human activities in coastal zones of the delta, man-dominated tidal flats have become the main kind of tidal flats.展开更多
Guizhou Province is an important karst area in the world and a fragile ecological area in China. Ecological risk assessment is very necessary to be conducted in this region. This study investigates different character...Guizhou Province is an important karst area in the world and a fragile ecological area in China. Ecological risk assessment is very necessary to be conducted in this region. This study investigates different characteristics of the spatial-temporal changes of vegetation cover in Guizhou Province of Southern China using the data set of SPOT VEGETATION(1999–2015) at spatial resolution of 1-km and temporal resolution of 10-day. The coefficient of variation, the Theil-Sen median trend analysis, and the Mann-Kendall test are used to investigate the spatial-temporal change of vegetation cover and its future trend. Results show that: 1) the spatial distribution pattern of vegetation cover in Guizhou Plateau is high in the east whereas low in the west. The average annual normalized difference vegetation index(NDVI) from west to east is higher than that from south to north. 2) Average annual NDVI improved obviously in the past 17 years. The growth rate of average annual NDVI is 0.028/10 yr, which is slower than that of vegetation in the country(0.048/10 yr) from 1998 to 2007. Average annual NDVI in karst area is lower than that in non-karst area. However, the growing rate of average annual NDVI in karst area(0.030/10 yr) is faster than that in non-karst area(0.023/10 yr), indicating that vegetation coverage increases more rapidly in karst area. 3) Vegetation coverage in the study area is stable overall, but fluctuates in the local scales. 4) Vegetation coverage presents a continuous increasing trend. The Hurst exponent of NDVI in different vegetation types has an obvious threshold in various elevations. 5) The proportion of vegetation cover with sustainable increase is higher than that of vegetation cover with sustainable decrease. The improvement in vegetation cover may expand to most parts of the study area.展开更多
Urban agglomeration is caused by the continuous acceleration of the urbanization process in China. Studying the expansion of construction land can not only know the changes and development of urban agglomeration in ti...Urban agglomeration is caused by the continuous acceleration of the urbanization process in China. Studying the expansion of construction land can not only know the changes and development of urban agglomeration in time, but also obtain the great significance of the future management. In this study, taking Changsha-Zhuzhou-Xiangtan(Chang-Zhu-Tan) urban agglomeration in Hunan province as a study area, Landsat images from 1995 to 2014 and Autologistic-CLUE-S model simulation data were used. Moreover, several factors including gravity center, direction, distance and landscape index were considered in the analysis of the expansion. The results revealed that the construction area increased by 132.18%, from 372.28 km^2 in 1995 to 864.37 km^2 in 2014. And it might even reach 1327.23 km^2 in 2023. Before 2014, three cities had their own respective and discrete development directions. However, because of the integration policy implementation in 2008, the Chang-Zhu-Tan began to gather, the gravity center moved southward after 2014, and the distance between cities decreased, which was in line with the development plan of urban expansion. The research methods and results were relatively reliable, and these results could provide some reference for the future land use planning and spatial allocation in the urbanization process of Chang-Zhu-Tan urban agglomeration.展开更多
The research on the land use/cover change is one of the frontiers and the hot spots in the global change research. Based on the Chinese resource and environment spatial-temporal database, and using the ...The research on the land use/cover change is one of the frontiers and the hot spots in the global change research. Based on the Chinese resource and environment spatial-temporal database, and using the Landsat TM and ETM data of 1990 and 2000 respectively, we analyzed the spatial-temporal characteristics of land use/cover changes in the Dongting Lake area during the last decade. The result shows that during the last ten years there were three land-use types that had changed remarkably. The cultivated land decreased by 0.57% of the total cultivated land. The built-up land and water area expanded, with an increase of 8.97% and 0.43% respectively. The conversion between land use types mostly happened among these three land-use types, especially frequently between cultivated land and water area. The land-use change speed of land-use type is different. Three cities experienced the greatest degree of land-use change among all the administrative districts, which means that the land use in these cities changed much quickly. The following changed area was the west and south of the Dongting Lake area. The slowest changed area is the north and east area.展开更多
A ten-year chlorophyll-a concentration dataset from Moderate Resolution Imaging Spectro-radiometer(MODIS) were used to analyze the variation of phytoplankton biomass and its potential relation with climate in the East...A ten-year chlorophyll-a concentration dataset from Moderate Resolution Imaging Spectro-radiometer(MODIS) were used to analyze the variation of phytoplankton biomass and its potential relation with climate in the East China Sea. The result indicated that the phytoplankton biomass generally had a regular pattern every year, and phytoplankton bloom mainly occurred between May and July. The highest phytoplankton biomass appeared near the Yangtze River Estuary. The lowest phytoplankton biomass located near the Taiwan Strait. In general, the starting bloom time was earlier in the south than in the north, and the span time of the former was also longer. During the recent ten years, the phytoplankton biomass around the Yangtze River Estuary decreased obviously. The change of phytoplankton biomass was found to be related with the Ni?o3.4 Index. The correlation between the intensity of phytoplankton bloom with the number and square of red tide were 0.63 and 0.74, respectively.展开更多
Yushu Tibetan Autonomous Prefecture, an area located in the Qinghai-Tibet Plateau, is an area very sensitive to global climate change. Due to impacts from climate change and human disturbances, grassland vegetation in...Yushu Tibetan Autonomous Prefecture, an area located in the Qinghai-Tibet Plateau, is an area very sensitive to global climate change. Due to impacts from climate change and human disturbances, grassland vegetation in the area has been degraded and desertification has been expanding. Ecosystems in the area are very sensitive and fragile and ecological problems have become increasingly serious in the area, resulting in an adverse effect on the local socio-economic development and environment of Qinghai province. Using data gathered from Landsat TM/ETM images for 1987, 1997 and 2007, we analyzed landscape patterns across Yushu Prefecture. Spatial structure indices indicated that： （i） the area of grassland has significantly decreased in the form of degradation and conversion from grassland into bare land and farmland; （ii） grassy vegetation patches changed into fragmented and isolated patches; （iii） the main landscapes in Yushu Prefecture are grasslands, forests and rivers; （iv） patches of grass have reiatively high connectivity; and （v） landscape change is significantly correlated with human activities and climate change. This study provides a strong theoretical and technical basis for policy-making regarding environmental protection of and management in Yushu Prefecture of Qinghai Province.展开更多
Regional land use changes are an important part of global changes.The research on land use changes in the Three Gorges Reservoir Area of China attracts a lot of attention owing to the Three Gorges Dam building.The Thr...Regional land use changes are an important part of global changes.The research on land use changes in the Three Gorges Reservoir Area of China attracts a lot of attention owing to the Three Gorges Dam building.The Three Gorges Reservoir Area becomes one of the important research areas.This study analyzed the transforming processes and traits of each land use type and the regional differences of land use changes during the past 30 years,summarized the distribution of different land use types in different buffer zones and regresses the equation areas and different buffer distances based on buffer analyses and regression analyses,and then analyzed the transforming rules in different buffer distances,got the optimal influence distances.The research results indicate that,(1) cultivated land lies at the northwest of the reservoir and was decreasing,however,the construction land was increasing,especially the urban construction land,a large number of land was flooded because of the reservoir water level rise;(2) urban area was sprawling quickly in developed and neighboring areas,and a great deal of cultivated land and a considerable amount of grassland were occupied;in the earlier time,rural settlements occupied lots of cultivated land and a sum of forestry land in the later time;(3) the optimum influenced distances for cultivated land and forestry land were 10-35 km,and for urban and rural settlements were in 5-20 km.Overall,this research can reflect the spatial-temporal characteristics of land use changes during the 30 years,and it is helpful for urban planning and land use planning in the reservoir area.展开更多
Delimiting ecological space scientifically and making reasonable predictions of the spatial-temporal trend of changes in the dominant ecosystem service functions(ESFs) are the basis of constructing an ecological prote...Delimiting ecological space scientifically and making reasonable predictions of the spatial-temporal trend of changes in the dominant ecosystem service functions(ESFs) are the basis of constructing an ecological protection pattern of territorial space, which has important theoretical significance and application value. At present, most research on the identification, functional partitioning and pattern reconstruction of ecological space refers to the current ESFs and their structural information, which ignores the spatial-temporal dynamic nature of the comprehensive and dominant ESFs, and does not seriously consider the change simulation in the dominant ESFs of the future ecological space. This affects the rationality of constructing an ecological space protection pattern to some extent. In this study, we propose an ecological space delimitation method based on the dynamic change characteristics of the ESFs, realize the identification of the ecological space range in Qionglai City and solve the problem of ignoring the spatial-temporal changes of ESFs in current research. On this basis, we also apply the Markov-CA model to integrate the spatial-temporal change characteristics of the dominant ESFs, successfully realize the simulation of the spatial-temporal changes in the dominant ESFs in Qionglai City’s ecological space in 2025, find a suitable method for simulating ecological spatial-temporal changes and also provide a basis for constructing a reasonable ecological space protection pattern. This study finds that the comprehensive quantity of ESF and its annual rate of change in Qionglai City show obvious dynamics, which confirms the necessity of considering the dynamic characteristics of ESFs when identifying ecological space. The areas of ecological space in Qionglai city represent 98307 ha by using the ecological space identification method proposed in this study, which is consistent with the ecological spatial distribution in the local ecological civilization construction plan. This confirms the reliability of the ecological space identification method based on the dynamic characteristics of the ESFs. The results also show that the dominant ESFs in Qionglai City represented strong non-stationary characteristics during 2003–2019,which showed that we should fully consider the influence of the dynamics in the dominant ESFs on the future ESF pattern during the process of constructing the ecological spatial protection pattern. The Markov-CA model realized the simulation of spatial-temporal changes in the dominant ESFs with a high precision Kappa coefficient of above 0.95, which illustrated the feasibility of using this model to simulate the future dominant ESF spatial pattern. The simulation results showed that the dominant ESFs in Qionglai will still undergo mutual conversions during 2019–2025 due to the effect of the their non-stationary nature. The ecological space will still maintain the three dominant ESFs of primary product production, climate regulation and hydrological regulation in 2025, but their areas will change to 32793 ha, 52490 ha and 13024 ha, respectively. This study can serve as a scientific reference for the delimitation of the ecological conservation redline, ecological function regionalization and the construction of an ecological spatial protection pattern.展开更多
Existing literature is characterized by certain deficiencies in measuring housing bubbles in China. By extending the analytical framework of Black et al. （2006） to a spatial panel VAR structure, this paper measures ...Existing literature is characterized by certain deficiencies in measuring housing bubbles in China. By extending the analytical framework of Black et al. （2006） to a spatial panel VAR structure, this paper measures housing bubbles in China＇s 35 major cities from 1999Q2 to 2012Q3 and analyzes the spatial-temporal changes of the housing bubbles in these cities. Results indicate that 1） changes to housing bubbles in most cities highly correspond with changes in the main real estate policies of the country and 2） housing bubbles in eastern developed cities such as Beijing, Shanghai, Shenzhen, Hangzhou, and Ningbo, have been relatively large in recent years although the average housing bubble is not very serious over the 35 major cities. Through the Kernel Density Function and local indicators of spatial autocorrelation analysis, this paper finds that housing bubbles are concentrated in several eastern developed cities. Based on empirical analysis, this paper proposes policy recommendations on inhibiting the expansion and diffusion of housing bubbles.展开更多
The authors use a web crawler to retrieve all periodical articles from CNKI between the 1950 s and 2016 and then parse the abstracts of 293368 articles about grassland deterioration by word segmentation, location matc...The authors use a web crawler to retrieve all periodical articles from CNKI between the 1950 s and 2016 and then parse the abstracts of 293368 articles about grassland deterioration by word segmentation, location matching and other methods. The authors also construct a research hot regions extraction model of grassland deterioration in China based on a comprehensive research hot regions index of toponyms and then analyze the spatial pattern and dynamic change in research hot regions of grassland deterioration in China. The research shows the following：（1） The spatial heterogeneity of grassland deterioration in China can be effectively described by a model of grassland deterioration based on the comprehensive research hot regions index.（2） The research hot regions of grassland deterioration are mainly distributed in most regions of Inner Mongolia, Xinjiang, Qinghai, Tibet, Gansu and other provinces. The northeastern region of Inner Mongolia（such as Hulunbeier） and the eastern region of Inner Mongolia（such as Xilin Gol, Chifeng and Wulanchabu） are significant hot regions in the study of grassland deterioration.（3） The number of high research hot regions increases from 81 in the 1950 s to 99 in the 2000s; the area increases from 1.038 million km2 to 1.146 million km2. The degree of hot for grassland deterioration research in 197 counties showed an upward trend. This paper also discusses the relationship between the region of research hot regions and the region of grassland deterioration and then indicates the differences between them in time matching, space matching and concept matching.展开更多
To address the challenge of balancing thermal management and thermal runaway mitigation,it is crucial to explore effective methods for enhancing the safety of lithium-ion battery systems.Herein,an innovative hydrated ...To address the challenge of balancing thermal management and thermal runaway mitigation,it is crucial to explore effective methods for enhancing the safety of lithium-ion battery systems.Herein,an innovative hydrated salt composite phase change material(HSCPCM)with dual phase transition temperature zones has been proposed.This HSCPCM,denoted as SDMA10,combines hydrophilic modified expanded graphite,an acrylic emulsion coating,and eutectic hydrated salts to achieve leakage prevention,enhanced thermal stability,cycling stability,and superior phase change behavior.Battery modules incorporating SDMA10 demonstrate significant thermal control capabilities.Specifically,the cylindrical battery modules with SDMA10 can maintain maximum operating temperatures below 55°C at 4 C discharge rate,while prismatic battery modules can keep maximum operating temperatures below 65°C at 2 C discharge rate.In extreme battery overheating conditions simulated using heating plates,SDMA10 effectively suppresses thermal propagation.Even when the central heating plate reaches 300°C,the maximum temperature at the module edge heating plates remains below 85°C.Further,compared to organic composite phase change materials(CPCMs),the battery module with SDMA10 can further reduce the peak thermal runaway temperature by 93°C and delay the thermal runaway trigger time by 689 s,thereby significantly decreasing heat diffusion.Therefore,the designed HSCPCM integrates excellent latent heat storage and thermochemical storage capabilities,providing high thermal energy storage density within the thermal management and thermal runaway threshold temperature range.This research will offer a promising pathway for improving the thermal safety performance of battery packs in electric vehicles and other energy storage systems.展开更多
In this paper,we present a broadband,high-extinction-ratio,nonvolatile 2×2 Mach-Zehnder interfer⁃ometer(MZI)optical switch based on the phase change material Sb_(2)Se_(3).The insertion loss(IL)is 0.84 dB and the ...In this paper,we present a broadband,high-extinction-ratio,nonvolatile 2×2 Mach-Zehnder interfer⁃ometer(MZI)optical switch based on the phase change material Sb_(2)Se_(3).The insertion loss(IL)is 0.84 dB and the extinction ratio(ER)reaches 28.8 dB at the wavelength of 1550 nm.The 3 dB bandwidth is greater than 150 nm.Within the 3 dB bandwidth,the ER is greater than 20.3 dB and 16.3 dB at bar and cross states,respectively.The power consumption for crystallization and amorphization of Sb_(2)Se_(3) is 105.86 nJ and 49 nJ,respectively.The switch holds significant promise for optical interconnects and optical computing applications.展开更多
The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang...The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang for multiple years via a decision tree method based on a classification and regression tree(CART)algorithm using Landsat time series images.Spatiotemporal transform and fragmentation patterns of mangrove distribution were separately assessed with a transfer matrix of land cover types and a landscape pattern index.The classification method combined with multi-band images showed good accuracy,with overall accuracy higher than 90%.Mangrove areas in 1988,1999,2009,and 2019 were 2050,1875,1818,and 1750 ha,respectively,with decreases mainly due to conversion to aquaculture ponds and farmland.A mangrove growth index(MGI)was proposed,reflecting the water-mangrove relationship,showing positive mangrove growth from 1988–2009 and negative growth from 2009–2019.Study results indicated anthropogenic factors play a leading role in the extent and scale of mangrove effects over the past 30 years.According to the analysis results,corresponding management and protection measures are proposed to provide reference for the sustainable development of Dongzhaigang Mangrove Wetland ecosystem.展开更多
Tajikistan contains the majority of Central Asia’s glaciers,which cover about 6.00%of the national territory;their rapid shrinkage poses a significant threat to regional water resource security.However,glacier monito...Tajikistan contains the majority of Central Asia’s glaciers,which cover about 6.00%of the national territory;their rapid shrinkage poses a significant threat to regional water resource security.However,glacier monitoring in Tajikistan was interrupted after 1991,creating a substantial gap in understanding the current state and temporal evolution of these glaciers.Based on glacier inventory data,in situ measurements,and published literature,this study examined the present status and recent variations of glaciers in Tajikistan through data integration and validation,literature collation and comparative analysis,and the application of Geographic Information System(GIS)spatial analysis techniques.As of 2023,Tajikistan possesses a total of 11,528 glaciers,encompassing an area of 7624.48(±305.58)km2.Small glaciers dominate in number,whereas large glaciers account for the majority of the total area.Over the past two decades,the glacier count has decreased by 2014,and the total area has decreased by 628.98 km2,corresponding to an average annual reduction rate of 0.33%.Regional shrinkage rates range from 4.10%to 22.28%.Glaciers have undergone accelerated mass loss during the past 20 a;only those on the northeastern Pamir Plateau exhibit a weak positive mass balance.Observations of typical monitored glaciers also reveal intensified melting and retreat,consistent with regional trends.In light of the recent acceleration of glacier shrinkage in Tajikistan,focused measures should be implemented to strengthen glacier monitoring,enhance public awareness of glacier preservation,and promote the sustainable development and utilization of glacier tourism.These findings bridge the knowledge gap regarding the spatiotemporal dynamics of Tajikistan’s glaciers over recent decades and provide essential data support for regional water resource management.展开更多
With the rapid increase in the aging population comes a rise in the incidence and prevalence of neurodegenerative diseases.Therefore,it is critical to understand the molecular changes that occur,which can either cause...With the rapid increase in the aging population comes a rise in the incidence and prevalence of neurodegenerative diseases.Therefore,it is critical to understand the molecular changes that occur,which can either cause disease or make brains resilient.Epigenetic changes are a common suspect and target,not only because they are among the hallmarks of aging,but also because they are flexible and could potentially be reversed.展开更多
Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-netwo...Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-network description technologies are ineffective in representing the temporal and spatial characteristics simultaneously.Therefore,there is a need for complementary methods to address these deficiencies.To address these limitations,this paper proposes an approach that combines Network Snapshots and Temporal Paths for the scheduled system.A dual information network is constructed to assess the degree of operational deviation considering the planning tasks.To validate the effectiveness,discussions are conducted through a modified cosine similarity calculation on theoretical analysis,delay level description,and the ability to identify abnormal dates.Compared to some state-of-the-art methods,the proposed method achieves an average Spearman delay correlation of 0.847 and a relative distance of 3.477.Furthermore,case analyses are invested in regions of China's Mainland,Europe,and the United States,investigating both the overall and sub-regional network fluctuations.To represent the impact of network fluctuations in sub-regions,a response loss value was developed.The times that are prone to fluctuations are also discussed through the classification of time series data.The research can offer a novel approach to system monitoring,providing a research direction that utilizes individual data combined to represent macroscopic states.Our code will be released at https://github.com/daozhong/STPN.git.展开更多
In the context of the global energy low-carbon transition,phase change energy storage technology becomes a key technology to solve the problem of intermittent renewable energy.Oriented phase change composites(OCPCMs)r...In the context of the global energy low-carbon transition,phase change energy storage technology becomes a key technology to solve the problem of intermittent renewable energy.Oriented phase change composites(OCPCMs)receive widespread attention in practical energy storage applications due to their unique oriented thermally conductive structure,which achieves significant thermal conductivity enhancement in specific directions while retaining the high energy storage capacity of the phase change components.This review systematically summarizes the overall analysis of OCPCMs from synthesis and preparation to application scenarios in recent years.Herein,we introduce the analysis of the heat transfer mechanism of the materials and explore the advantages of the oriented structure in OCPCMs in the heat transfer behavior from a bionic perspective.We then focus on summarizing and generalizing the methods for preparing OCPCMs,giving suggestions for suitable methods according to different scenarios.Besides,we discuss the application of finite element simulation methods to the monitoring of the thermal management behavior of OCPCMs,and look into the potential future application areas of such materials.Finally,it is hoped that this review will provide guidance for the academic community in developing high-performance OCPCMs.展开更多
The accelerating impacts of climate change,rising temperatures,extreme weather events,and biodiversity loss underscore the urgent need for widespread public awareness.This research explores why climate change awarenes...The accelerating impacts of climate change,rising temperatures,extreme weather events,and biodiversity loss underscore the urgent need for widespread public awareness.This research explores why climate change awareness is not just beneficial but essential for effective environmental stewardship and the long-term health of our planet.The research proffers informed communities,encouraging sustainable practices,and driving policy advocacy,awareness serves as a model for collective action.This call to consciousness challenges individuals,institutions,and nations to recognize their role in shaping a resilient,sustainable future for the Earth.Methodology adopted in this research is a mixed-method design,involving both qualitative and quasi-experimental designs,which engages the use of focus group discussions and oral interviews to explore deeper insights into perceptions,biodiversity loss consciousness,and environmental depletion challenges.Also,applicable under the qualitative method is the secondary data collection mode,namely,reports from IPCC,government policy documents,and existing literature related to the context of the research.The empirical and scientific data analysis was presented from the data collected and was coded and subjected to analysis using a paired samples t-test.The study is grounded on the theory of“Value-Belief-Norm”(VBN)developed by Stern et al.The VBN theory posits that individuals are more likely to engage in pro-environmental behaviour when their values(especially biosphere and altruistic),beliefs(about environmental consequences),and norms(personal responsibility to act)align.The findings of this study underscore the critical role of climate change awareness in fostering environmental and earth stewardship.The paper recommends that Governments of the country(State and federal)should take urgent steps in sensitising the general public on the causes and impact of climate change.展开更多
Starting from the foundational static traits underlying the growth and development of flue-cured tobacco, this research conducts a systematic examination of the phenomena and theoretical principles associated with env...Starting from the foundational static traits underlying the growth and development of flue-cured tobacco, this research conducts a systematic examination of the phenomena and theoretical principles associated with environment-driven adaptive changes during its cultivation. It was found that environmental variables-including temperature, light, and moisture-elicit directional shifts in static traits ( e.g. , chemical composition, morphological architecture, and leaf tissue structure) toward enhanced environmental adaptation, characterized by graduality, juvenility, similarity, and correlativity. Upon alterations in ambient conditions, flue-cured tobacco modulates its static traits through integrated physical, chemical, and biological-genetic mechanisms, aiming to optimize resource utilization, mitigate environmental constraints, and preserve internal homeostasis alongside metabolic balance. The investigation further reveals that the adaptive scope of flue-cured tobacco to field environments is malleable and can be extended and elevated via adaptive conditioning commencing at the juvenile stage. In addition, the adaptive alignment between static traits and environmental parameters exerts a substantial impact on the plant s growth dynamics, yield performance, and quality attributes. Beyond its relevance to flue-cured tobacco, the proposed theory offers a meaningful framework for elucidating the pervasive adaptive strategies employed by plants and broader biological systems in response to environmental contingencies.展开更多
基金the National Key Basic Research Support Foundation of China (No. 2002CB111502), the NationalNatural Science Foundation of China (Nos. 40371074 and 40025106) and the China Postdoctoral Science Foundation(No. 2003033023).
文摘To probe the processes and mechanisms of soil organic carbon (SOC) changes during forest recovery, a 150-yearchronosequence study on SOC was conducted for various vegetation succession stages at the Ziwuling area, in the centralpart of the Loess Plateau, China. Results showed that during the 150 years of local vegetation rehabilitation SOC increasedsignificantly (P < 0.05) over time in the initial period of 55-59 years, but slightly decreased afterwards. Average SOCdensities for the 0-100 cm layer of farmland, grassland, shrubland and forest were 4.46, 5.05, 9.95, and 7.49 kg C m-3,respectively. The decrease in SOC from 60 to 150 years of abandonment implied that the soil carbon pool was a sink forCO2 before the shrubland stage and became a source in the later period. This change resulted from the spatially variedcomposition and structure of the vegetation. Vegetation recovery had a maximum effect on the surface (0-20 cm) SOCpool. It. was concluded that vegetation recovery on the Loess Plateau could result in significantly increased sequestrationof atmospheric CO2 in soil and vegetation, which was ecologically important for mitigating the increase of atmosphericconcentration of CO2 and for ameliorating the local eco-environment.
基金National Natural Science Foundation of China No.40176021 No.50339050
文摘Integrating remote sensing, geographic information system (GIS) and fractal theory, change characteristics of tidal flats and tidal creeks in the Huanghe (Yellow) River Delta over the period of 1986-2001 were discussed. The results show that evolutions of tidal flats throughout the Huanghe River Delta are influenced by various factors, and that progressive succession and regression of tidal flats concur in different coastal segments of the delta. Human activities have played an increasingly important role in the succession process of tidal flats. Due to land reclamation in coastal zones of the delta in the last 15 years, lots of tidal flats were occupied, the artificial coastline migrated seaward (the maximum change rate was 0.8 kmyr-1) and tidal creeks became sparser (the highest decreasing rate of length of tidal creeks was 14.9 kmyr-1). Except for two coastal segments from the Tiaohe Estuary to the 106 Station and from the south of the Huanghe River mouth to the north of the Xiaodao River Estuary, fractal dimension values of tidal creeks in the remaining coastal segments of the delta decreased. In addition, the time dimension, sediment fluxes into the sea, waves and tidal-currents have profound influences on the evolution process of tidal flats. Four types of tidal flats-river-dominated tidal flats, tide-dominated tidal flats, wave-dominated tidal flats and man-dominated tidal flats can be identified. Owing to the intensification of human activities in coastal zones of the delta, man-dominated tidal flats have become the main kind of tidal flats.
基金Under the auspices of National Key Research Program of China(No.2016YFC0502300,2016YFC0502102,2014BAB03B00)National Key Research and Development Program(No.2014BAB03B02)+3 种基金Agricultural Science and Technology Key Project of Guizhou Province of China(No.2014-3039)Science and Technology Plan Projects of Guiyang Municipal Bureau of Science and Technology of China(No.2012-205)Science and Technology Plan of Guizhou Province of China(No.2012-6015)Guangxi Natural Science Foundation of China(No.2014GXNSFBA118221)
文摘Guizhou Province is an important karst area in the world and a fragile ecological area in China. Ecological risk assessment is very necessary to be conducted in this region. This study investigates different characteristics of the spatial-temporal changes of vegetation cover in Guizhou Province of Southern China using the data set of SPOT VEGETATION(1999–2015) at spatial resolution of 1-km and temporal resolution of 10-day. The coefficient of variation, the Theil-Sen median trend analysis, and the Mann-Kendall test are used to investigate the spatial-temporal change of vegetation cover and its future trend. Results show that: 1) the spatial distribution pattern of vegetation cover in Guizhou Plateau is high in the east whereas low in the west. The average annual normalized difference vegetation index(NDVI) from west to east is higher than that from south to north. 2) Average annual NDVI improved obviously in the past 17 years. The growth rate of average annual NDVI is 0.028/10 yr, which is slower than that of vegetation in the country(0.048/10 yr) from 1998 to 2007. Average annual NDVI in karst area is lower than that in non-karst area. However, the growing rate of average annual NDVI in karst area(0.030/10 yr) is faster than that in non-karst area(0.023/10 yr), indicating that vegetation coverage increases more rapidly in karst area. 3) Vegetation coverage in the study area is stable overall, but fluctuates in the local scales. 4) Vegetation coverage presents a continuous increasing trend. The Hurst exponent of NDVI in different vegetation types has an obvious threshold in various elevations. 5) The proportion of vegetation cover with sustainable increase is higher than that of vegetation cover with sustainable decrease. The improvement in vegetation cover may expand to most parts of the study area.
基金National Natural Science Foundation of China,No.41571077National Key Research and Development Program of China,No.2016YFC0503002
文摘Urban agglomeration is caused by the continuous acceleration of the urbanization process in China. Studying the expansion of construction land can not only know the changes and development of urban agglomeration in time, but also obtain the great significance of the future management. In this study, taking Changsha-Zhuzhou-Xiangtan(Chang-Zhu-Tan) urban agglomeration in Hunan province as a study area, Landsat images from 1995 to 2014 and Autologistic-CLUE-S model simulation data were used. Moreover, several factors including gravity center, direction, distance and landscape index were considered in the analysis of the expansion. The results revealed that the construction area increased by 132.18%, from 372.28 km^2 in 1995 to 864.37 km^2 in 2014. And it might even reach 1327.23 km^2 in 2023. Before 2014, three cities had their own respective and discrete development directions. However, because of the integration policy implementation in 2008, the Chang-Zhu-Tan began to gather, the gravity center moved southward after 2014, and the distance between cities decreased, which was in line with the development plan of urban expansion. The research methods and results were relatively reliable, and these results could provide some reference for the future land use planning and spatial allocation in the urbanization process of Chang-Zhu-Tan urban agglomeration.
基金Knowledge Innovation Project of CAS No.KZCX2-310-01+1 种基金 No.KZCX2-SW-415 No.KZCX1-Y-02
文摘The research on the land use/cover change is one of the frontiers and the hot spots in the global change research. Based on the Chinese resource and environment spatial-temporal database, and using the Landsat TM and ETM data of 1990 and 2000 respectively, we analyzed the spatial-temporal characteristics of land use/cover changes in the Dongting Lake area during the last decade. The result shows that during the last ten years there were three land-use types that had changed remarkably. The cultivated land decreased by 0.57% of the total cultivated land. The built-up land and water area expanded, with an increase of 8.97% and 0.43% respectively. The conversion between land use types mostly happened among these three land-use types, especially frequently between cultivated land and water area. The land-use change speed of land-use type is different. Three cities experienced the greatest degree of land-use change among all the administrative districts, which means that the land use in these cities changed much quickly. The following changed area was the west and south of the Dongting Lake area. The slowest changed area is the north and east area.
基金supported by the National Key Research and Development Project of China (No. 2019YFD0901405)the Open Project Program of the Scientific Observing and Experimental Station of Fishery Remote Sensing,Ministry of Agriculture (No. OFSOESFRS201501)+2 种基金the Central Public-Interest Scientific Institution Basal Research Fund (CAFS)(No. 2018HY-ZD0103)the Open Research Fund of State Key Laboratory of Estuarine and Coastal Research (No. SKLEC-KF201805)the Fujian Provincial Key Laboratory of Marine Fishery Resources and Eco-Environment Funding (No. fjmfre2019003)。
文摘A ten-year chlorophyll-a concentration dataset from Moderate Resolution Imaging Spectro-radiometer(MODIS) were used to analyze the variation of phytoplankton biomass and its potential relation with climate in the East China Sea. The result indicated that the phytoplankton biomass generally had a regular pattern every year, and phytoplankton bloom mainly occurred between May and July. The highest phytoplankton biomass appeared near the Yangtze River Estuary. The lowest phytoplankton biomass located near the Taiwan Strait. In general, the starting bloom time was earlier in the south than in the north, and the span time of the former was also longer. During the recent ten years, the phytoplankton biomass around the Yangtze River Estuary decreased obviously. The change of phytoplankton biomass was found to be related with the Ni?o3.4 Index. The correlation between the intensity of phytoplankton bloom with the number and square of red tide were 0.63 and 0.74, respectively.
基金National Natural Science Foundation of China (No.30970506)111 project of MUC(B.08004)
文摘Yushu Tibetan Autonomous Prefecture, an area located in the Qinghai-Tibet Plateau, is an area very sensitive to global climate change. Due to impacts from climate change and human disturbances, grassland vegetation in the area has been degraded and desertification has been expanding. Ecosystems in the area are very sensitive and fragile and ecological problems have become increasingly serious in the area, resulting in an adverse effect on the local socio-economic development and environment of Qinghai province. Using data gathered from Landsat TM/ETM images for 1987, 1997 and 2007, we analyzed landscape patterns across Yushu Prefecture. Spatial structure indices indicated that： （i） the area of grassland has significantly decreased in the form of degradation and conversion from grassland into bare land and farmland; （ii） grassy vegetation patches changed into fragmented and isolated patches; （iii） the main landscapes in Yushu Prefecture are grasslands, forests and rivers; （iv） patches of grass have reiatively high connectivity; and （v） landscape change is significantly correlated with human activities and climate change. This study provides a strong theoretical and technical basis for policy-making regarding environmental protection of and management in Yushu Prefecture of Qinghai Province.
基金supported by the National Science and Technology Support Project(Grant No.2006BAB15B03)
文摘Regional land use changes are an important part of global changes.The research on land use changes in the Three Gorges Reservoir Area of China attracts a lot of attention owing to the Three Gorges Dam building.The Three Gorges Reservoir Area becomes one of the important research areas.This study analyzed the transforming processes and traits of each land use type and the regional differences of land use changes during the past 30 years,summarized the distribution of different land use types in different buffer zones and regresses the equation areas and different buffer distances based on buffer analyses and regression analyses,and then analyzed the transforming rules in different buffer distances,got the optimal influence distances.The research results indicate that,(1) cultivated land lies at the northwest of the reservoir and was decreasing,however,the construction land was increasing,especially the urban construction land,a large number of land was flooded because of the reservoir water level rise;(2) urban area was sprawling quickly in developed and neighboring areas,and a great deal of cultivated land and a considerable amount of grassland were occupied;in the earlier time,rural settlements occupied lots of cultivated land and a sum of forestry land in the later time;(3) the optimum influenced distances for cultivated land and forestry land were 10-35 km,and for urban and rural settlements were in 5-20 km.Overall,this research can reflect the spatial-temporal characteristics of land use changes during the 30 years,and it is helpful for urban planning and land use planning in the reservoir area.
基金The Sichuan Science and Technology Program (2020YFS0335, 2021YFH0121)The National College Students’ Innovative Entrepreneurial Training Plan Program of Sichuan Agricultural University (202110626038)The Double Support Program Project of Discipline Construction of Sichuan Agricultural University of China (2018, 2019, 2020)。
文摘Delimiting ecological space scientifically and making reasonable predictions of the spatial-temporal trend of changes in the dominant ecosystem service functions(ESFs) are the basis of constructing an ecological protection pattern of territorial space, which has important theoretical significance and application value. At present, most research on the identification, functional partitioning and pattern reconstruction of ecological space refers to the current ESFs and their structural information, which ignores the spatial-temporal dynamic nature of the comprehensive and dominant ESFs, and does not seriously consider the change simulation in the dominant ESFs of the future ecological space. This affects the rationality of constructing an ecological space protection pattern to some extent. In this study, we propose an ecological space delimitation method based on the dynamic change characteristics of the ESFs, realize the identification of the ecological space range in Qionglai City and solve the problem of ignoring the spatial-temporal changes of ESFs in current research. On this basis, we also apply the Markov-CA model to integrate the spatial-temporal change characteristics of the dominant ESFs, successfully realize the simulation of the spatial-temporal changes in the dominant ESFs in Qionglai City’s ecological space in 2025, find a suitable method for simulating ecological spatial-temporal changes and also provide a basis for constructing a reasonable ecological space protection pattern. This study finds that the comprehensive quantity of ESF and its annual rate of change in Qionglai City show obvious dynamics, which confirms the necessity of considering the dynamic characteristics of ESFs when identifying ecological space. The areas of ecological space in Qionglai city represent 98307 ha by using the ecological space identification method proposed in this study, which is consistent with the ecological spatial distribution in the local ecological civilization construction plan. This confirms the reliability of the ecological space identification method based on the dynamic characteristics of the ESFs. The results also show that the dominant ESFs in Qionglai City represented strong non-stationary characteristics during 2003–2019,which showed that we should fully consider the influence of the dynamics in the dominant ESFs on the future ESF pattern during the process of constructing the ecological spatial protection pattern. The Markov-CA model realized the simulation of spatial-temporal changes in the dominant ESFs with a high precision Kappa coefficient of above 0.95, which illustrated the feasibility of using this model to simulate the future dominant ESF spatial pattern. The simulation results showed that the dominant ESFs in Qionglai will still undergo mutual conversions during 2019–2025 due to the effect of the their non-stationary nature. The ecological space will still maintain the three dominant ESFs of primary product production, climate regulation and hydrological regulation in 2025, but their areas will change to 32793 ha, 52490 ha and 13024 ha, respectively. This study can serve as a scientific reference for the delimitation of the ecological conservation redline, ecological function regionalization and the construction of an ecological spatial protection pattern.
文摘Existing literature is characterized by certain deficiencies in measuring housing bubbles in China. By extending the analytical framework of Black et al. （2006） to a spatial panel VAR structure, this paper measures housing bubbles in China＇s 35 major cities from 1999Q2 to 2012Q3 and analyzes the spatial-temporal changes of the housing bubbles in these cities. Results indicate that 1） changes to housing bubbles in most cities highly correspond with changes in the main real estate policies of the country and 2） housing bubbles in eastern developed cities such as Beijing, Shanghai, Shenzhen, Hangzhou, and Ningbo, have been relatively large in recent years although the average housing bubble is not very serious over the 35 major cities. Through the Kernel Density Function and local indicators of spatial autocorrelation analysis, this paper finds that housing bubbles are concentrated in several eastern developed cities. Based on empirical analysis, this paper proposes policy recommendations on inhibiting the expansion and diffusion of housing bubbles.
基金National Key Research and Development Plan Program(2016YFC0503701,2016YFB0501502)Key Project of High Resolution Earth Observation System(00-Y30B14-9001-14/16)
文摘The authors use a web crawler to retrieve all periodical articles from CNKI between the 1950 s and 2016 and then parse the abstracts of 293368 articles about grassland deterioration by word segmentation, location matching and other methods. The authors also construct a research hot regions extraction model of grassland deterioration in China based on a comprehensive research hot regions index of toponyms and then analyze the spatial pattern and dynamic change in research hot regions of grassland deterioration in China. The research shows the following：（1） The spatial heterogeneity of grassland deterioration in China can be effectively described by a model of grassland deterioration based on the comprehensive research hot regions index.（2） The research hot regions of grassland deterioration are mainly distributed in most regions of Inner Mongolia, Xinjiang, Qinghai, Tibet, Gansu and other provinces. The northeastern region of Inner Mongolia（such as Hulunbeier） and the eastern region of Inner Mongolia（such as Xilin Gol, Chifeng and Wulanchabu） are significant hot regions in the study of grassland deterioration.（3） The number of high research hot regions increases from 81 in the 1950 s to 99 in the 2000s; the area increases from 1.038 million km2 to 1.146 million km2. The degree of hot for grassland deterioration research in 197 counties showed an upward trend. This paper also discusses the relationship between the region of research hot regions and the region of grassland deterioration and then indicates the differences between them in time matching, space matching and concept matching.
基金financially supported by Natural Science Foundation of Guangdong province(2024A1515010228)CATARC Automotive Inspection Center Excellent Engineer Program(2023B0909050007).
文摘To address the challenge of balancing thermal management and thermal runaway mitigation,it is crucial to explore effective methods for enhancing the safety of lithium-ion battery systems.Herein,an innovative hydrated salt composite phase change material(HSCPCM)with dual phase transition temperature zones has been proposed.This HSCPCM,denoted as SDMA10,combines hydrophilic modified expanded graphite,an acrylic emulsion coating,and eutectic hydrated salts to achieve leakage prevention,enhanced thermal stability,cycling stability,and superior phase change behavior.Battery modules incorporating SDMA10 demonstrate significant thermal control capabilities.Specifically,the cylindrical battery modules with SDMA10 can maintain maximum operating temperatures below 55°C at 4 C discharge rate,while prismatic battery modules can keep maximum operating temperatures below 65°C at 2 C discharge rate.In extreme battery overheating conditions simulated using heating plates,SDMA10 effectively suppresses thermal propagation.Even when the central heating plate reaches 300°C,the maximum temperature at the module edge heating plates remains below 85°C.Further,compared to organic composite phase change materials(CPCMs),the battery module with SDMA10 can further reduce the peak thermal runaway temperature by 93°C and delay the thermal runaway trigger time by 689 s,thereby significantly decreasing heat diffusion.Therefore,the designed HSCPCM integrates excellent latent heat storage and thermochemical storage capabilities,providing high thermal energy storage density within the thermal management and thermal runaway threshold temperature range.This research will offer a promising pathway for improving the thermal safety performance of battery packs in electric vehicles and other energy storage systems.
基金Supported by the National Natural Science Foundation of China(62204250)Autonomous deployment project of State Key Laboratory of Materials for Integrated Circuits(SKLJC-Z2024-A05).
文摘In this paper,we present a broadband,high-extinction-ratio,nonvolatile 2×2 Mach-Zehnder interfer⁃ometer(MZI)optical switch based on the phase change material Sb_(2)Se_(3).The insertion loss(IL)is 0.84 dB and the extinction ratio(ER)reaches 28.8 dB at the wavelength of 1550 nm.The 3 dB bandwidth is greater than 150 nm.Within the 3 dB bandwidth,the ER is greater than 20.3 dB and 16.3 dB at bar and cross states,respectively.The power consumption for crystallization and amorphization of Sb_(2)Se_(3) is 105.86 nJ and 49 nJ,respectively.The switch holds significant promise for optical interconnects and optical computing applications.
基金financially supported by the National Natural Science Foundation of China(Nos.U2244225 and 42020104005)the Ministry of Education of China(111 Project)the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)and China Geological Survey(No.DD20211391)。
文摘The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang for multiple years via a decision tree method based on a classification and regression tree(CART)algorithm using Landsat time series images.Spatiotemporal transform and fragmentation patterns of mangrove distribution were separately assessed with a transfer matrix of land cover types and a landscape pattern index.The classification method combined with multi-band images showed good accuracy,with overall accuracy higher than 90%.Mangrove areas in 1988,1999,2009,and 2019 were 2050,1875,1818,and 1750 ha,respectively,with decreases mainly due to conversion to aquaculture ponds and farmland.A mangrove growth index(MGI)was proposed,reflecting the water-mangrove relationship,showing positive mangrove growth from 1988–2009 and negative growth from 2009–2019.Study results indicated anthropogenic factors play a leading role in the extent and scale of mangrove effects over the past 30 years.According to the analysis results,corresponding management and protection measures are proposed to provide reference for the sustainable development of Dongzhaigang Mangrove Wetland ecosystem.
基金supported by the National Key R&D Plan“Inter-governmental International Science&Technology Innovation Cooperation”Key Specialized Program,China(2025YFE0102800)the Program of the State Key Laboratory of Cryospheric Science and Frozen Soil Engineering,Chinese Academy of Sciences(CSFSE-ZZ-2403).
文摘Tajikistan contains the majority of Central Asia’s glaciers,which cover about 6.00%of the national territory;their rapid shrinkage poses a significant threat to regional water resource security.However,glacier monitoring in Tajikistan was interrupted after 1991,creating a substantial gap in understanding the current state and temporal evolution of these glaciers.Based on glacier inventory data,in situ measurements,and published literature,this study examined the present status and recent variations of glaciers in Tajikistan through data integration and validation,literature collation and comparative analysis,and the application of Geographic Information System(GIS)spatial analysis techniques.As of 2023,Tajikistan possesses a total of 11,528 glaciers,encompassing an area of 7624.48(±305.58)km2.Small glaciers dominate in number,whereas large glaciers account for the majority of the total area.Over the past two decades,the glacier count has decreased by 2014,and the total area has decreased by 628.98 km2,corresponding to an average annual reduction rate of 0.33%.Regional shrinkage rates range from 4.10%to 22.28%.Glaciers have undergone accelerated mass loss during the past 20 a;only those on the northeastern Pamir Plateau exhibit a weak positive mass balance.Observations of typical monitored glaciers also reveal intensified melting and retreat,consistent with regional trends.In light of the recent acceleration of glacier shrinkage in Tajikistan,focused measures should be implemented to strengthen glacier monitoring,enhance public awareness of glacier preservation,and promote the sustainable development and utilization of glacier tourism.These findings bridge the knowledge gap regarding the spatiotemporal dynamics of Tajikistan’s glaciers over recent decades and provide essential data support for regional water resource management.
基金David and Inez Myers Foundation,the Israeli Ministry of Science and Technology(MOST)The Israel Science Foundation(No.422/23)(to DT).
文摘With the rapid increase in the aging population comes a rise in the incidence and prevalence of neurodegenerative diseases.Therefore,it is critical to understand the molecular changes that occur,which can either cause disease or make brains resilient.Epigenetic changes are a common suspect and target,not only because they are among the hallmarks of aging,but also because they are flexible and could potentially be reversed.
文摘Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-network description technologies are ineffective in representing the temporal and spatial characteristics simultaneously.Therefore,there is a need for complementary methods to address these deficiencies.To address these limitations,this paper proposes an approach that combines Network Snapshots and Temporal Paths for the scheduled system.A dual information network is constructed to assess the degree of operational deviation considering the planning tasks.To validate the effectiveness,discussions are conducted through a modified cosine similarity calculation on theoretical analysis,delay level description,and the ability to identify abnormal dates.Compared to some state-of-the-art methods,the proposed method achieves an average Spearman delay correlation of 0.847 and a relative distance of 3.477.Furthermore,case analyses are invested in regions of China's Mainland,Europe,and the United States,investigating both the overall and sub-regional network fluctuations.To represent the impact of network fluctuations in sub-regions,a response loss value was developed.The times that are prone to fluctuations are also discussed through the classification of time series data.The research can offer a novel approach to system monitoring,providing a research direction that utilizes individual data combined to represent macroscopic states.Our code will be released at https://github.com/daozhong/STPN.git.
基金financially supported by the Fundamental Research Funds for the Central Universities(No.FRF-KST-25-001)the Beijing Natural Science Foundation(No.L253029)。
文摘In the context of the global energy low-carbon transition,phase change energy storage technology becomes a key technology to solve the problem of intermittent renewable energy.Oriented phase change composites(OCPCMs)receive widespread attention in practical energy storage applications due to their unique oriented thermally conductive structure,which achieves significant thermal conductivity enhancement in specific directions while retaining the high energy storage capacity of the phase change components.This review systematically summarizes the overall analysis of OCPCMs from synthesis and preparation to application scenarios in recent years.Herein,we introduce the analysis of the heat transfer mechanism of the materials and explore the advantages of the oriented structure in OCPCMs in the heat transfer behavior from a bionic perspective.We then focus on summarizing and generalizing the methods for preparing OCPCMs,giving suggestions for suitable methods according to different scenarios.Besides,we discuss the application of finite element simulation methods to the monitoring of the thermal management behavior of OCPCMs,and look into the potential future application areas of such materials.Finally,it is hoped that this review will provide guidance for the academic community in developing high-performance OCPCMs.
文摘The accelerating impacts of climate change,rising temperatures,extreme weather events,and biodiversity loss underscore the urgent need for widespread public awareness.This research explores why climate change awareness is not just beneficial but essential for effective environmental stewardship and the long-term health of our planet.The research proffers informed communities,encouraging sustainable practices,and driving policy advocacy,awareness serves as a model for collective action.This call to consciousness challenges individuals,institutions,and nations to recognize their role in shaping a resilient,sustainable future for the Earth.Methodology adopted in this research is a mixed-method design,involving both qualitative and quasi-experimental designs,which engages the use of focus group discussions and oral interviews to explore deeper insights into perceptions,biodiversity loss consciousness,and environmental depletion challenges.Also,applicable under the qualitative method is the secondary data collection mode,namely,reports from IPCC,government policy documents,and existing literature related to the context of the research.The empirical and scientific data analysis was presented from the data collected and was coded and subjected to analysis using a paired samples t-test.The study is grounded on the theory of“Value-Belief-Norm”(VBN)developed by Stern et al.The VBN theory posits that individuals are more likely to engage in pro-environmental behaviour when their values(especially biosphere and altruistic),beliefs(about environmental consequences),and norms(personal responsibility to act)align.The findings of this study underscore the critical role of climate change awareness in fostering environmental and earth stewardship.The paper recommends that Governments of the country(State and federal)should take urgent steps in sensitising the general public on the causes and impact of climate change.
基金Supported by Changsha Tobacco Company Science and Technology Project(2020-2024A04).
文摘Starting from the foundational static traits underlying the growth and development of flue-cured tobacco, this research conducts a systematic examination of the phenomena and theoretical principles associated with environment-driven adaptive changes during its cultivation. It was found that environmental variables-including temperature, light, and moisture-elicit directional shifts in static traits ( e.g. , chemical composition, morphological architecture, and leaf tissue structure) toward enhanced environmental adaptation, characterized by graduality, juvenility, similarity, and correlativity. Upon alterations in ambient conditions, flue-cured tobacco modulates its static traits through integrated physical, chemical, and biological-genetic mechanisms, aiming to optimize resource utilization, mitigate environmental constraints, and preserve internal homeostasis alongside metabolic balance. The investigation further reveals that the adaptive scope of flue-cured tobacco to field environments is malleable and can be extended and elevated via adaptive conditioning commencing at the juvenile stage. In addition, the adaptive alignment between static traits and environmental parameters exerts a substantial impact on the plant s growth dynamics, yield performance, and quality attributes. Beyond its relevance to flue-cured tobacco, the proposed theory offers a meaningful framework for elucidating the pervasive adaptive strategies employed by plants and broader biological systems in response to environmental contingencies.
