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Impact of climate change and human activities on the spatiotemporal dynamics of surface water area in Gansu Province, China
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作者 LU Haitian ZHAO Ruifeng +3 位作者 ZHAO Liu LIU Jiaxin LYU Binyang YANG Xinyue 《Journal of Arid Land》 SCIE CSCD 2024年第6期798-815,共18页
Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with comp... Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with complex terrain and variable climate,as the research subject.Based on Google Earth Engine,we used Landsat data and the Open-surface Water Detection Method with Enhanced Impurity Control method to monitor the spatiotemporal dynamics of surface water area in Gansu Province from 1985 to 2022,and quantitatively analyzed the main causes of regional differences in surface water area.The findings revealed that surface water area in Gansu Province expanded by 406.88 km2 from 1985 to 2022.Seasonal surface water area exhibited significant fluctuations,while permanent surface water area showed a steady increase.Notably,terrestrial water storage exhibited a trend of first decreasing and then increasing,correlated with the dynamics of surface water area.Climate change and human activities jointly affected surface hydrological processes,with the impact of climate change being slightly higher than that of human activities.Spatially,climate change affected the'source'of surface water to a greater extent,while human activities tended to affect the'destination'of surface water.Challenges of surface water resources faced by inland arid and semi-arid areas like Gansu Province are multifaceted.Therefore,we summarized the surface hydrology patterns typical in inland arid and semi-arid areas and tailored surface water'supply-demand'balance strategies.The study not only sheds light on the dynamics of surface water area in Gansu Province,but also offers valuable insights for ecological protection and surface water resource management in inland arid and semi-arid areas facing water scarcity. 展开更多
关键词 surface water area terrestrial water storage Open-surface Water Detection Method with Enhanced Impurity Control method Google Earth Engine climate change human activities inland arid and semi-arid areas
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Effect of acetylcholine on pain-related electric activities in hippocampal CA1 area of normal and morphinistic rats
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作者 肖宇 杨晓芳 徐满英 《Neuroscience Bulletin》 SCIE CAS CSCD 2007年第6期323-328,共6页
Objective To examine the effect of acetylcholine(ACh)on the electric activities of pain-excitation neurons (PEN)and pain-inhibitation neurons(PIN)in the hippocampal CA1 area of normal rats or morphinistic rats,a... Objective To examine the effect of acetylcholine(ACh)on the electric activities of pain-excitation neurons (PEN)and pain-inhibitation neurons(PIN)in the hippocampal CA1 area of normal rats or morphinistic rats,and to explore the role of ACh in regulation of pain perception in CA1 area under normal condition and morphine addiction.Methods The trains of electric impulses applied to sciatic nerve were set as noxious stimulation.The discharges of PEN and PIN in the CA l area were recorded extracellularly by glass microelectrode.We observed the influence of intracerebroventricular (i.c.v.)injection of ACh and atropine on the noxious stimulation-evoked activities of PEN and PIN in the CA1 area.Results Noxious stimulation enhanced the electric activity of PEN and depressed that of PIN in the CA1 area of both normal and addiction rats.In normal rats,ACh decrease the pain-evoked discharge frequency of PEN,while increased the frequency of PIN.These effects reached the peak value at 4 min after injection of ACh.In morphinistic rats,ACh also inhibited the PEN electric activity and potentialized the PIN electric activity,but the maximum effect appeared at 6 min after administration. The ACh-induced responses were significantly blocked by muscarinic receptor antagonist atropine.Conclusion Cholinergic neurons and muscarinic receptors in the hippocampal CA1 area are involved in the processing of nociceptive information and they may play an analgesia role in pain modulation.Morphine addiction attenuated the sensitivity of painrelated neurons to the noxious information. 展开更多
关键词 ACETYLCHOLINE hippocampal CA1 area MORPHINE electric activity
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Spatio-temporal Pattern of Net Primary Productivity in Hengduan Mountains area, China: Impacts of Climate Change and Human Activities 被引量:12
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作者 CHEN Tiantian PENG Li +1 位作者 LIU Shaoquan WANG Qiang 《Chinese Geographical Science》 SCIE CSCD 2017年第6期948-962,共15页
Net primary productivity(NPP), a metric used to define and identify changes in plant communities, is greatly affected by climate change, human activities and other factors. Here, we used the Carnegie-Ames-Stanford App... Net primary productivity(NPP), a metric used to define and identify changes in plant communities, is greatly affected by climate change, human activities and other factors. Here, we used the Carnegie-Ames-Stanford Approach(CASA) model to estimate the NPP of plant communities in Hengduan Mountains area of China, and to explore the relationship between NPP and altitude in this region. We examined the mechanisms underlying vegetation growth responses to climate change and quantitatively assessed the effects of ecological protection measures by partitioning the contributions of climate change and human activities to NPP changes. The results demonstrated that: 1) the average total and annual NPP values over the years were 209.15 Tg C and 468.06 g C/(m2·yr), respectively. Their trend increasingly fluctuated, with spatial distribution strongly linked to altitude(i.e., lower and higher NPP in high altitude and low altitude areas, respectively) and 2400 m represented the marginal altitude for vegetation differentiation; 2) areas where climate was the main factor affecting NPP accounted for 18.2% of the total research area, whereas human activities were the primary factor influencing NPP in 81.8% of the total research area, which indicated that human activity was the main force driving changes in NPP. Areas where climatic factors(i.e., temperature and precipitation) were the main driving factors occupied 13.6%(temperature) and 6.0%(precipitation) of the total research area, respectively. Therefore, the effect of temperature on NPP changes was stronger than that of precipitation; and 3) the majority of NPP residuals from 2001 to 2014 were positive, with human activities playing an active role in determining regional vegetation growth, possibly due to the return of farmland back to forest and natural forest protection. However, this positive trend is decreasing. This clearly shows the periodical nature of ecological projects and a lack of long-term effectiveness. 展开更多
关键词 net primary productivity (NPP) Carnegie-Ames-Stanford Approach (CASA) model climate change human activities Hengduan Mountains area
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A cultivated area forecasting approach in artificial oases under climate change and human activities 被引量:1
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作者 ZHANG Shaobo CHEN Fulong +3 位作者 CHEN Jie WANG Jing LI Shaofei LONG Aihua 《Journal of Arid Land》 SCIE CSCD 2019年第3期400-418,共19页
The cultivated area in artificial oases is deeply influenced by global climate change and human activities.Thus,forecasting cultivated area in artificial oases under climate change and human activities is of great sig... The cultivated area in artificial oases is deeply influenced by global climate change and human activities.Thus,forecasting cultivated area in artificial oases under climate change and human activities is of great significance.In this study,an approach named GD-HM-PSWROAM,consisting of general circulation model downscaling(GD),hydrological model(HM),and planting structure and water resource optimal allocation model(PSWROAM),was developed and applied in the irrigation district of the Manas River Basin in Xinjiang Uygur Autonomous Region of China to forecast the cultivated area tendency.Furthermore,the catchment export of the MIKE11 HD/NAM model was set to the Kensiwate hydrological station.The results show that the downscaling effects of temperature can be fairly satisfying,while those of precipitation may be not satisfying but acceptable.Simulation capacity of the MIKE11 HD/NAM model on the discharge in the Kensiwate hydrological station can meet the requirements of running the PSWROAM.The accuracy of the PSWROAM indicated that this model can perform well in predicting the change of cultivated area at the decadal scale.The cultivated area in the Manas River Basin under current human activities may be generally decreasing due to the climate change.But the adverse effects of climate change can be weakened or even eliminated through positive human activities.The cultivated area in the Manas River Basin may even be increasing under assumed human activities and future climate scenarios.The effects of human activities in the future can be generally predicted and quantified according to the cultivated area trends under current human activities and the situations in the study area.Overall,it is rational and acceptable to forecast the cultivated area tendency in artificial oases under future climate change and human activities through the GD-HM-PSWROAM approach. 展开更多
关键词 GCM DOWNSCALING HYDROLOGICAL model CULTIVATED area climate change human activities MANAS River Basin
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Monitoring and Evaluation of Present Situation of Environmental Quality in the Sea Area near the Aojiang Estuary in Wenzou 被引量:1
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作者 Ye Maosen Yang Dan +4 位作者 Zhang Rongbao Xu Hengtao Zhang Haisheng Yao Dongping Ye Xinrong 《Meteorological and Environmental Research》 CAS 2017年第3期57-61,66,共6页
Based on the monitoring results of environmental quality in the sea area near the Aojiang estuary in Wenzou during 2010-2012,the present situation of environmental quality in the sea area was analyzed and evaluated. T... Based on the monitoring results of environmental quality in the sea area near the Aojiang estuary in Wenzou during 2010-2012,the present situation of environmental quality in the sea area was analyzed and evaluated. The results show that p H,DO,CODMn,petroleum,and heavy metals( Cu,Pb,Zn,Cd,Hg,As and Cr) in the sea area near the Aojiang estuary did not exceed the second-class standard of Seawater Quality Standard( GB 3097-1997),but both inorganic nitrogen and reactive phosphate in the sea area exceeded the second-class standard seriously,and the water quality of the sea area was in an eutrophic state; domestic sewage and fertilizer loss were the main sources of nitrogen and phosphorus. The standard index of most evaluation factors of sediment quality except for Zn was smaller than 1,meeting the demands of sediment quality for environmental protection. 展开更多
关键词 Sea area NEAR the Aojiang ESTUARY in Wenzou PRESENT situation of environmental QUALITY Monitoring Evaluation Water QUALITY Sediment QUALITY
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Study on the Countermeasures of Eco-environment Conservation in the Mountainous Areas of Southern Ningxia under New Situation 被引量:1
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作者 JIA Yao-feng School of Management,North China University of Nationalities,Yinchuan 750021,China 《Meteorological and Environmental Research》 CAS 2011年第3期53-56,72,共5页
Under the implementation of principal functional zoning,further promotion of western development,regional migration,new countryside construction,global warming and so on,the spatial adjustment of regional industry and... Under the implementation of principal functional zoning,further promotion of western development,regional migration,new countryside construction,global warming and so on,the spatial adjustment of regional industry and its structure must be enforced.The spatial adjustment and arrangement of population and economy in the mountainous areas of southern Ningxia could create tremendous opportunity for its eco-environment conservation.Based on analysis on the opportunity and challenge of eco-environment conservation in the mountainous areas of southern Ningxia,some countermeasures of eco-environment conservation were discussed in the paper,so as to provide some theoretical references for the eco-environment conservation in the mountainous areas of southern Ningxia. 展开更多
关键词 Mountainous areas of southern Ningxia New situation Eco-environment conservation COUNTERMEASURE China
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Current Situation of Information Demand of Farmers in Taihang Mountain Area: A Case Study of Pingshan County in Hebei Province 被引量:2
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作者 Lipeng GUO Haiyan CAI 《Asian Agricultural Research》 2014年第7期22-25,30,共5页
Since the reform and opening-up,economy of mountain areas in China has realized considerable development.However,due to such factors as terrain,traffic,and individual differences,compared with plain and coastal areas,... Since the reform and opening-up,economy of mountain areas in China has realized considerable development.However,due to such factors as terrain,traffic,and individual differences,compared with plain and coastal areas,mountain areas still lag far behind.In recent years,informationization construction of China develops rapidly,but it nearly stagnates in mountain rural areas.Information has become an essential factor restricting economic development of rural areas.Based on the survey of current information demand of farmers carried out in Pingshan County in Hebei Province in 2010,this study came up with relevant recommendations,in order to speed up development of rural economic in mountain areas,narrow the regional gap,improve living condition of farmers in mountain areas,and increase income level of farmers in mountain areas. 展开更多
关键词 Pingshan COUNTY Taihang MOUNTAIN area FARMERS INFO
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Situational interest impacts college students’physical activity in a design-based bike exergame
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作者 Denis Pasco Cédric Roure 《Journal of Sport and Health Science》 SCIE 2022年第2期172-178,I0002,共8页
Background:Active videogames or exergames have been used as an innovative way to promote physical activity(PA)among various populations.A player’s interest in active videogames is associated with the fun and entertai... Background:Active videogames or exergames have been used as an innovative way to promote physical activity(PA)among various populations.A player’s interest in active videogames is associated with the fun and entertaining nature of the games and may trigger situational interest,thus increasing engagement.The goal of this study was to examine the impact of situational interest dimensions on college students’PA when playing the design-based bike exergame Greedy Rabbit(Vescape,Berlin,Germany).Methods:Sixty undergraduate students(age:20.8±1.3 years,mean±SD,18-25 years old;51.7%males)were recruited from the kinesiology department of a university located in the southern region of Belgium.The participants were assigned to an experimental group(n=41)or a control group(n=19)based on an incremental cycling test.Students in the experimental group engaged in 1 session of Greedy Rabbit(Vescape)while students in the control group engaged in 1 session of a placebo version of Greedy Rabbit(Vescape).The length of the sessions ranged from 24 min to 31 min.Results:Results for the control group indicated that the players’PA metrics(cadence:F(19,360)=1.43,p=0.11;heart rate:F(19.360)=1.16,p=0.29;oxygen consumption:F(19,360)=0.83,p=0.67)were stable during the exergame.Results for the experimental group demonstrated the effects of time on the players’PA metrics and revealed significant associations between the change in the players’situational interest dimensions and PA metrics(cadence:F(19,800)=26.30,p<0.01;heart rate:F(19,800)=19.77,p<0.01;oxygen consumption:F(19,800)=10.04,p<0.01).Conclusion:An approach using a design-based exergame may be a relevant strategy for promoting levels of PA that yields positive health-related outcomes among college students. 展开更多
关键词 active videogame College students Exergame Physical activity situational interest
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Current Situation,Problems and Development Strategies of Marine Ecological Civilization Demonstration Areas in China
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作者 Teng Yunhao Qu Qunzhen 《Meteorological and Environmental Research》 CAS 2014年第6期20-22,27,共4页
Based on analysis of current situation of national marine ecological civilization demonstration areas in China, problems were discussed from aspects of shoreline development, marine disaster waming, marine pollution, ... Based on analysis of current situation of national marine ecological civilization demonstration areas in China, problems were discussed from aspects of shoreline development, marine disaster waming, marine pollution, etc. Afterwards, some development strategies were proposed to provide references for construction of marine ecological civilization demonstration areas in China, thereby promoting overall construction of marine ecological civilization in China. 展开更多
关键词 Marine ecological civilization demonstration areas Current situation PROBLEMS STRATEGIES China
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Assessing the Vulnerability of Agricultural Production Activities in the Coastal Area of Thua Thien Hue Province, Vietnam by GIS Analysis Tools
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作者 Nguyen Hoang Son Dao Dinh Cham +2 位作者 Phan Anh Hang Nguyen Trong Quan Nguyen Thanh Hoan 《Journal of Geoscience and Environment Protection》 2019年第5期116-130,共15页
Using Geography Information System (GIS) tools and remote sensing data in assessing the level of vulnerability of agricultural production activities in the coastal area has become more efficient in the recent years. T... Using Geography Information System (GIS) tools and remote sensing data in assessing the level of vulnerability of agricultural production activities in the coastal area has become more efficient in the recent years. This research has identified the sensitivity index (S) (including the traffic access index;the impact of residential areas;the impacts of industrial zones;the community dependence level), exposure index (E) (the sea level rises to 2100;the temperature change to 2100), the adaptable capacity index (AC) (slope;morphology), thereby synthesizing the vulnerability index (V). Based on the indexes to calculate vulnerability, the high to very high vulnerability area is 37,081.44 ha, accounting for 68.09%;the average vulnerability level is 15,286.49 ha, accounting for 28.07%;the low to very low vulnerability level with an area is 2087.82 ha, accounting for 3.84% of the total area. With a high and very high vulnerability accounting for 68.09%, there will be great influences on the lives of resident in the area, especially agricultural production. 展开更多
关键词 VULNERABILITY Indexes GIS TOOLS AGRICULTURAL Production activity COASTAL areas
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Centurial Evolution of an Offshore Mud Deposition Area in the Changjiang (Yangtze) Estuary and Its Links to Environmental and Anthropogenic Activities
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作者 CONG Jingyi HU Gang +4 位作者 JONELL Tara N YUAN Zhongpeng KONG Xianghuai ZHANG Yong WANG Yonghong 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第4期790-800,共11页
Large amounts of sediments originating from the Changjiang(Yangtze)River are deposited in the subaqueous delta and in the adjacent muddy area off the mouth and on the inner shelf of the East China Sea.The terrestrial ... Large amounts of sediments originating from the Changjiang(Yangtze)River are deposited in the subaqueous delta and in the adjacent muddy area off the mouth and on the inner shelf of the East China Sea.The terrestrial sediments deposited in these areas not only contain information about the composition and environment of the source area,but they also record changes in anthropogenic activities.A sediment piston core(CJ0702)was extracted from the Changjiang subaqueous depocenter(31.00°N,122.67°E)in a water depth of 22.0 m.The core was subsampled at 1–2 cm intervals and analyzed for grain size,clay mineralogy,and major element geochemistry.Results indicate a relatively high sediment accumulation rate of approximately 3.11 cm yr−1.These parameters exhibited only minor cyclical fluctuations in the core,which resulted from many factors.During the past 120 years,the Changjiang River-derived sediment is the primary source of sediment in the offshore mud area without evidence for the Yellow River-derived sediment increasing.After the trunk stream shifted from the North Branch to South Branch,the variations of proxies are controlled by the periodic fluctuation possibly linked to El Niño-Southern Oscillation(ENSO)and the Pacific Decadal Oscillation(PDO).In addition,anthropogenic heavy metal concentrations can be divided into three stages,which coincide well with economic development and environmental protection policies. 展开更多
关键词 sedimentary evolution mud area Changjiang(Yangtze)Estuary sediment transport anthropogenic activity
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Proactive Saudi Arabia:Actively Tackling the Regional Ever-changing Situation
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作者 Liao Baizhi 《Contemporary International Relations》 2017年第5期11-19,共9页
There is chaos in the Gulf region. Saudi Arabia in conjunction with the United Arab Emirates, Bahrain, Egypt and other gulf countries,suddenly cut off diplomatic relations with Qatar expelling diplomats and citizens, ... There is chaos in the Gulf region. Saudi Arabia in conjunction with the United Arab Emirates, Bahrain, Egypt and other gulf countries,suddenly cut off diplomatic relations with Qatar expelling diplomats and citizens, exerting blockades on land, sea and aviation on June 5, 2017, with the excuse that Qatar supports terrorism- and damages regional security. Sandi Arabia and other gulf countries have issued an ultimatum on June 23, giving Qatar to 10 days to meet their 13 requirements. For a time, the Saudi-led group became the media hot word. The Gulf, once a rare peaceful land under the impact of the Arab Spring, now falls into chaos. The GCC in fact has split. This is another major diplomatic adventure that Saudi Arabia has taken in recent years. 展开更多
关键词 Proactive Saudi Arabia actively Tackling the Regional Ever-changing situation
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Analysis of the Synoptic Situation Field on the Red Tide Occurred in Yangtze River Estuary Water Area
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作者 Peng Mo Liu Shoudong +1 位作者 Liu Ming Pan Xishan 《International Journal of Technology Management》 2014年第11期112-114,共3页
The occurrence of the red tide is an extremely complex process, which is considered as the comprehensive result of various factors. The Yangtze River estuary water area is always in high incidence area of red tide. In... The occurrence of the red tide is an extremely complex process, which is considered as the comprehensive result of various factors. The Yangtze River estuary water area is always in high incidence area of red tide. In this paper, according to the events of red tide and meteorologic and hydrologic data in Yangtze River estuary water area from 2000 to 2010, by using mathematical statistics methods, we analyze the relevance between the occurrence of the red tide and the synoptic situation field, and probe into the regular patterns. 展开更多
关键词 Yangtze River estuary water area red tide synoptic situation field
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Current Situation,Problems and Countermeasures of Modern Agricultural Construction in Bijie Experimental Area
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作者 Rongda ZHANG 《Asian Agricultural Research》 2013年第9期25-28,共4页
Firstly,the current situation and existing problems of modern agricultural construction in Bijie experimental area were analyzed,and then the countermeasures of promoting construction and sustainable development of mo... Firstly,the current situation and existing problems of modern agricultural construction in Bijie experimental area were analyzed,and then the countermeasures of promoting construction and sustainable development of modern agriculture were proposed according to the reality of agricultural development in the Bijie experimental area. 展开更多
关键词 Bijie EXPERIMENTAL area MODERN AGRICULTURE CURRENT
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Influence of Global Warming on High-active Agricultural Development in Chaoyang Area 被引量:1
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作者 周广学 李普庆 周晓东 《Meteorological and Environmental Research》 CAS 2010年第3期42-44,共3页
The warming effect of Chaoyang efficient agriculture was analyzed using nearly 60 years of climatic date and 30 years of agricultural material from three aspects including corn cultivation area,facility agriculture in... The warming effect of Chaoyang efficient agriculture was analyzed using nearly 60 years of climatic date and 30 years of agricultural material from three aspects including corn cultivation area,facility agriculture in protective field,gross agricultural output value.The results showed that climate warming had a very significant positive effect on the development of high-active agriculture in Chaoyang. 展开更多
关键词 Chaoyang area INFLUENCE High-active agriculture China
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Activation of brain areas following ankle dorsiflexion versus plantar flexion Functional magnetic resonance imaging verification 被引量:1
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作者 Tianyu Jiang Weiping Wu +3 位作者 Xinglin Wang Changshui Weng Qiuhua Wang Yanmei Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第7期501-505,共5页
Changes in activated areas of the brain during ankle active dorsiflexion and ankle active plantar flexion were observed in six healthy subjects using functional magnetic resonance imaging. Excited areas of ankle activ... Changes in activated areas of the brain during ankle active dorsiflexion and ankle active plantar flexion were observed in six healthy subjects using functional magnetic resonance imaging. Excited areas of ankle active dorsiflexion involved the bilateral primary motor area and the primary somatosensory area, as well as the bilateral supplementary sensory area, the primary visual area, the right second visual area, and the vermis of cerebellum. Excited areas of ankle active plantar flexion included the ipsilateral supplementary motor area, the limbic system, and the contralateral corpus striatum. Fine movements of the cerebral cortex control the function of the ankle dorsiflexion to a larger extent than ankle plate flexion, and the function of ankle plate flexion is more controlled by the subcortical area. 展开更多
关键词 ankle dorsiflexion ankle plantar flexion functional magnetic resonance imaging brain function activated areas
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A Framework of Massively Parallel Analysis of Regional Earthquake Activities 被引量:1
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作者 ZHANG Huai SHI Yaolin WU Zhongliang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第4期786-800,共15页
Recent rapid progress in cyberinfrastructure in geosciences is providing seismologists an enormous boost for addressing multi-physical phenomena of regional seismic activities. The inherent nature of their multi-scale... Recent rapid progress in cyberinfrastructure in geosciences is providing seismologists an enormous boost for addressing multi-physical phenomena of regional seismic activities. The inherent nature of their multi-scale properties, from temporal to spatial spaces, makes it inevitably to be solved using large-scale computations and distributed parallel data processing schemes. Under such circumstance, using the advanced numerical algorithms and unstructured mesh generation technologies become the obstacles for modern seismologists. The main objective of this paper is to present a framework, which includes a parallel finite element simulation and distributed data infrastructure, to address the novel algorithms, state-of-the-art modeling and their implementation in regional seismicgenic systems. We also discuss and implement this framework to analyze the strong earthquake evolution processes in the Sichuan-Yunnan region. This study is the key to long-term seismic risk by estimates, providing a platform for predictive large-scale numerical simulation modeling of regional earthquake activities. 展开更多
关键词 regional earthquake activities parallel numerical modeling initial stress field Sichuan- Yunnan area
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Interdecadal and decadal variation of temperature over North Pole area and the relation with solar activity 被引量:1
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作者 QU Weizheng ZHAO Jinping DU Ling HUANG Fei FAN Tingting 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第2期53-61,共9页
Obvious tendency and periodicity of the air temperature can be detected over the North Pole area.They are reflected as follows: a.the air temperature at the earth surface and in the middle layer of the stratosphere t... Obvious tendency and periodicity of the air temperature can be detected over the North Pole area.They are reflected as follows: a.the air temperature at the earth surface and in the middle layer of the stratosphere tends to be increased either in winter or in summer.The air temperature has increased 1.3 °C for about 50 years at a speed about 0.025 °C/year in January,and 0.013 °C/year in July.The air temperature in the middle layer of the stratosphere (10 hPa) in January has increased 10 °C.The temperature rising speed in July is 0.14 °C/year.Generally speaking,the temperature rising speed is quicker in winter than in summer and quicker in the upper layer than at the earth surface.b.The air temperature at the top layer of the troposphere (100 hPa) over the North Pole area tends to be increased either in winter or in summer.The air temperature in January has decreased 5.0 °C for about 50 years at a temperature decreasing speed about 0.094 °C/year,and at a temperature decreasing speed about 0.032 °C/year in July.The speed of the temperature decreasing is greater in winter than in summer.c.Periodicity.The air temperature respectively at different altitudes over the North Pole possesses interdecadal variation with a period of 22 years.In July the amplitude of the variation with a period of 22 years decreases rapidly from the high altitude to the low.This means that the 22–year’s period is more obvious at the high altitude than at the low altitude.At the earth surface layer in North Pole there also is obvious decadal variation with a period of 11 years.The analysis indicates that the 22-years’ period temperature variation is associated with the periodic variation of the solar magnetic field.The 11-year period temperature variation is corresponding to 11 year’ period of the variation of the sunspot number. 展开更多
关键词 decadal variation of air temperature solar activity North Pole area
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Coastal Environmental Changes and Management in China in the Context of Global Changes and Human Activities 被引量:1
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作者 Yunfeng ZHANG Yingying CHEN +2 位作者 Xiaobin HUA Shiqing YAN Lili ZOU 《Asian Agricultural Research》 2019年第7期24-30,33,共8页
Coastal zone is the complex area with intense sea-land interaction. There are various types, complex environments and developed economy in coastal area of China. Under the influence of global change and human activiti... Coastal zone is the complex area with intense sea-land interaction. There are various types, complex environments and developed economy in coastal area of China. Under the influence of global change and human activities, the ecosystem of coastal zone is vulnerable and has sensitive response to environment changes. The environmental problems of sea-level rising have attached close attention by countries all over the world. As far as regions concerned, relative sea-level rising is more important than theoretical sea-level rising. The relative sea-level rising has resulted in series of environment disasters in coastal area of China, such as coastal erosion, seawater invasion, and floods in coastal lowlands, etc. The flux of sediments transported by rivers into sea is the main material source of marine pollution. The human activities are controlling factors of variations in river sediment loads. Under the influence of high strength development in the upstream region, the results are that the reduction of seagoing sediments in main rivers of China, and damage of coastal material balance. Land-based pollution is the main source of marine pollution. With rapid economic development in China s eastern coastal, pollutants flux into sea increase gradually. The results are that the environmental quality and seawater quality of marine have being deteriorated and pollution is serious increasingly. To meet the land demand of industrialization and urbanization, the sea reclamation has become an effective means to alleviate the contradiction between human and land in coastal area of China. This leads to large-scale reduction of coastal wetland area, and the heavy losses of ecological service value of coastal wetland. To face the environmental changes in coastal area of China and solve the contradiction among population, resources, environment, development, it is required to set up the system concept of man-land-sea relationship, so as to achieve sustainable development. The feasible measures include improving coastal management system, strengthening integrated basin management, attaching importance to construction of the coastal environment engineering, and raising the environmental monitoring and early warning level. 展开更多
关键词 Costal areas ENVIRONMENTAL changes Human activities Integrated management
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Analysis of the world oil and gas exploration situation in 2021 被引量:2
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作者 DOU Lirong WEN Zhixin +4 位作者 WANG Jianjun WANG Zhaoming HE Zhengjun LIU Xiaobing ZHANG Ningning 《Petroleum Exploration and Development》 CSCD 2022年第5期1195-1209,共15页
The global exploration investment, new oil and gas discoveries, exploration business adjustment strategies of oil companies in 2021, and future favorable exploration domains are systematically analyzed using commercia... The global exploration investment, new oil and gas discoveries, exploration business adjustment strategies of oil companies in 2021, and future favorable exploration domains are systematically analyzed using commercial databases such as IHS and public information of oil companies. It has been found that the world oil and gas exploration situation in 2021 has continued the downturn since the outbreak of COVID-19. The investment and drilling workload decreased slightly, but the success rate of exploration wells, especially deepwater exploration wells, increased significantly, and the newly discovered reserves increased slightly compared with last year. Deep waters of the passive continental margin basins are still the leading sites for discovering conventional large and medium-sized oil and gas fields. The conventional oil and gas exploration in deep formations of onshore petroliferous basins has been keeping a good state, with tight/shale oil and gas discoveries made in Saudi Arabia, Russia, and other countries. While strengthening the exploration and development of local resources, national, international, and independent oil companies have been focusing on major overseas frontiers using their advantages, including risk exploration in deep waters and natural gas. Future favorable exploration directions in the three major frontiers, the global deep waters, deep onshore formations, and unconventional resources, have been clarified. Four suggestions are put forward for the global exploration business of Chinese oil companies: first, a farm in global deepwater frontier basins in advance through bidding at a low cost and adopt the “dual exploration model” after making large-scale discoveries;second, enter new blocks of emerging hot basins in the world through farm-in and other ways, to find large oil and gas fields quickly;third, cooperate with national oil companies of the resource host countries in the form of joint research and actively participate exploration of deep onshore formations of petroliferous basins;fourth, track tight/shale oil and gas cooperation opportunities in a few countries such as Saudi Arabia and Russia, and take advantage of mature domestic theories and technologies to farm in at an appropriate time. 展开更多
关键词 exploration investment exploration situation new discoveries favorable exploration areas overseas oil and gas exploration deep water deep formation unconventional resources
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