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Predicting Acute Mountain Sickness Using Regional Sea-Level Cerebral Blood Flow
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作者 Hao Zhang Jie Feng +2 位作者 Shiyu Zhang Wenjia Liu Lin Ma 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第8期887-896,共10页
Objective To investigate the role of sea-level cerebral blood flow(CBF)in predicting acute mountain sickness(AMS)using three-dimensional pseudo-continuous arterial spin labeling(3D-pCASL).Methods Forty-eight healthy v... Objective To investigate the role of sea-level cerebral blood flow(CBF)in predicting acute mountain sickness(AMS)using three-dimensional pseudo-continuous arterial spin labeling(3D-pCASL).Methods Forty-eight healthy volunteers reached an altitude of 3,650 m by air after undergoing a head magnetic resonance imaging(MRI)including 3D-pCASL at sea level.The CBF values of the bilateral anterior cerebral artery(ACA),middle cerebral artery(MCA),posterior cerebral artery(PCA),and posterior inferior cerebellar artery(PICA)territories and the laterality index(LI)of CBF were compared between the AMS and non-AMS groups.Statistical analyses were performed to determine the relationship between CBF and AMS,and the predictive performance was assessed using receiver operating characteristic(ROC)curves.Results The mean cortical CBF in women(81.65±2.69 mL/100 g/min)was higher than that in men(74.35±2.12 mL/100 g/min)(P<0.05).In men,the cortical CBF values in the bilateral ACA,PCA,PICA,and right MCA were higher in patients with AMS than in those without.Cortical CBF in the right PCA best predicted AMS(AUC=0.818).In women,the LI of CBF in the ACA was different between the AMS and non-AMS groups and predicted AMS with an AUC of 0.753.Conclusion Although the mechanism and prediction of AMS are quite complicated,higher cortical CBF at sea level,especially the CBF of the posterior circulatory system,may be used for prediction in male volunteers using non-invasive 3D-pCASL. 展开更多
关键词 Acute mountain sickness High-altitude headache Cerebral blood flow Arterial spin labeling Magnetic resonance imaging
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Socio-scientific quantification of the comprehensive benefits of debris flow mitigation measures for villages in western Sichuan, China
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作者 DENG Ting XU Pei +4 位作者 LI Ming LU Yafeng WANG Yukuan LI Zhengyang SHRAVAN Kumar Ghimire 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1598-1612,共15页
Debris flow hazards seriously threaten thesafety and sustainable development of mountainousareas. Numerous debris flow mitigation measures havebeen implemented worldwide;however, acomprehensive assessment of the speci... Debris flow hazards seriously threaten thesafety and sustainable development of mountainousareas. Numerous debris flow mitigation measures havebeen implemented worldwide;however, acomprehensive assessment of the specific disasterreduction effects of these measures and their economic,social and ecological benefits is yet to be performed.The western region of Sichuan Province frequentlysuffers from geohazards such as debris flow, and thegovernment has adopted many mitigation measures.This study assessed the benefits of debris flowmitigation measures and identified the key influencingfactors via a field-based study conducted in 81 villagesin western Sichuan province, China. A framework forthe evaluation of the benefits of rural debris flowmitigation measures was constructed andquantitatively evaluated using a survey. Snowballsampling was performed to recruit 81 village leadersand 468 farmers. The results showed that managementand engineering measures were the main methodsused to mitigate debris flow;ecological measures wereauxiliary. The average satisfaction scores of farmers forthese three types of measures were 4.07, 3.90, and 3.56,respectively (as measured on a five-point Likert scale).In contrast, in terms of the benefits of these mitigationmeasures, only a small proportion of villages (11.11%)obtained a high level of comprehensive benefits fromthe debris flow mitigation measures, while the majority(88.89%) received medium to low-level benefits. Toimprove this situation, we further studied and foundthat the main factors that restricted villages fromachieving high-level comprehensive benefits were theunpredictable nature of debris flows, labour forceoutflow and remoteness. Effective control measures, agood economic environment and strong governmentassistance were reported as crucial factors forimproving these comprehensive benefits. This studyprovides socio-scientific references for decisionmakingon rural debris flow mitigation measures while keeping villages at the centre of economic development. 展开更多
关键词 Mitigation measures Comprehensive benefit evaluation Debris flow mountain development Rural areas
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A system-integrated approach for the design of tourist areas at the local level under changing conditions:A case study in the Altay Mountains
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作者 Alexandr Nikolaevich DUNETS Evgeniya Mikhailovna TABAKAEVA HAN Fang 《Regional Sustainability》 2024年第2期89-102,共14页
The existing approaches for the design of tourist areas often lead to limited flexibility in project implementation.To realize a more flexible approach,in this study,we formulated a model for planning and designing to... The existing approaches for the design of tourist areas often lead to limited flexibility in project implementation.To realize a more flexible approach,in this study,we formulated a model for planning and designing tourist areas at the local level.Moreover,specific tools for analyzing tourist areas and ensuring sustainable development under changing conditions were developed.This study was conducted in two tourist regions,Biryuzovaya Katun tourist complex and Belokurikha destination(including Belokurikha City with Belokurikha 2 Gornaya tourist complex and surrounding areas),in the Altay Mountains.We employed the recreation opportunity spectrum and proposed a system-integrated programming approach for the design of tourist areas at the destination and site levels.The key of this approach was the collection and analysis of current spatial data,including the spatial distribution of attractions and visitor flows.We constructed heat maps using video recording and unmanned aerial vehicle(UAV)observation data.Moreover,we analyzed the video stream using an image-analyzing framework You Only Look Once(YOLO)v5 software.The heat map of visitor flows based on video recording data in the Andreevskaya Sloboda museum of Belokurikha 2 Gornaya tourist complex allowed us to highlight the most attractive sites in this area and classify them into one of three types:points of functional concentration,points of transitional concentration,and points of attractions.The heat maps in Biryuzovaya Katun tourist complex,created using UAV observation data,allowed us to determine the spatiotemporal patterns of visitor flows and tourists’preferences throughout the day within four time intervals:09:00-12:00,13:00-14:00,14:00-15:00,and 16:00-18:00(LST).The maximum visitor flow density occurred from 16:00 to 18:00 in the beach area of the artificial lake.A comparison between the visitor-concentrated sites and the current facilities provided insights into the demand for attractions and facilities and the lacking areas.Heat maps are useful in analyzing the land use at the site level,while zoning based on the recreation opportunity spectrum can be used to design tourist areas at the destination level.The proposed methods for analyzing the use of tourist areas contribute to the development of adaptive tourism design. 展开更多
关键词 Tourism planning Tourist areas Unmanned aerial vehicle(UAV) Visitor flows Heat map Altay mountains
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Disaster Reduction Decision Support System Against Debris Flows and Landslides Along Highway in Mountainous Area 被引量:4
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作者 Li Fa-bin, Wei Fang-qiang, Cui Peng, Zhou Wan-cunInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, Sichuan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期1012-1020,共9页
Highways in mountainous areas are easy to be damaged by such natural disasters as debris flows and landslides and disaster reduction decision support system (DRDSS) is one of the important means to mitigate these disa... Highways in mountainous areas are easy to be damaged by such natural disasters as debris flows and landslides and disaster reduction decision support system (DRDSS) is one of the important means to mitigate these disasters. Guided by the theories and technologies of debris flow and landslide reduction and supported by geographical information system (GIS), remote sensing and database techniques, a DRDSS against debris flow and landslide along highways in mountainous areas has been established on the basis of such principles as pertinence, systematicness, effectiveness, easy to use, open and expandability. The system consists of database, disaster analysis models and decisions on reduction of debris flows and landslides, mainly functioning to zone disaster dangerous degree, analyze debris flow activity, simulate debris flow deposition and diffusion, analyze landslide stability, select optimal highway renovation scheme and plan disaster prevention and control engineering. This system has been applied successfully to the debris flow and landslide treatment works along Palongzangbu Section of Sichuan-Tibet Highway. 展开更多
关键词 decision support system disaster reduction debris flow LANDSLIDE highway in mountainous areas
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The Modified Envelope Orography and the Air Flow over and around Mountains 被引量:7
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作者 李龙 朱抱真 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第3期249-260,共12页
By use of the two-layer adiabatic globe spectral model and the zonally averaged climatic data of winter season as initial values, 10-day integrations are carried out based on three kinds of model topography (i.e., (1)... By use of the two-layer adiabatic globe spectral model and the zonally averaged climatic data of winter season as initial values, 10-day integrations are carried out based on three kinds of model topography (i.e., (1) the averaged topography; (2) the envelope topography; (3) the modified envelope topography). The results show that the orography of the Northern Hemisphere plays an important role in the simulation of large-scale weather patterns in winter season. The simulation based on the envelope topography developed by Wallace et al. has some improvements in the Rocky Mountains area. But this scheme causes very serious horizontal expansion around the Tibetan Plateau (hereafter referred to as the TV). A modified envelope topography scheme has been worked out that increases the slope of the TP by decreasing the horizontal expansion while keeping the maximum altitude. The results show some improvements of the scheme around the TP. By analysis of the mechanical effects of the large-scale orography on the currents, the different forcings of the air flow over and around the TP and the Rocky Mountain (the RM) are investigated. 展开更多
关键词 AVE ENV The Modified Envelope Orography and the Air flow over and around mountains OVER
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Numerical analysis of landslide-generated debris flow on July 3, 2021 in Izu Mountain area, Shizuoka County, Japan 被引量:1
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作者 SUN Tong SUN Dong-ya +3 位作者 WANG Xie-kang MA Qiang GOURBESVILLE Philippe NOHARA Daisuke 《Journal of Mountain Science》 SCIE CSCD 2022年第6期1738-1747,共10页
With the increasing of extreme rainfall frequency, landslides accompanied by mudslides often lead to serious casualties and property damage. On 3rd July 2021, a debris flow occurred in Izu Mountain area, Shizuoka Coun... With the increasing of extreme rainfall frequency, landslides accompanied by mudslides often lead to serious casualties and property damage. On 3rd July 2021, a debris flow occurred in Izu Mountain area, Shizuoka County, Japan, and then resulted in 26 deaths and 131 houses destroyed, where houses were mainly built along the banks of the creek. In order to analyse the landslide state and distribution, a two-dimensional debris flow dynamic model(Massflow) was selected to simulate the process of the landslide-generated debris flow. When the model results are considered together with remote sensing images, the volume distribution of the unstable landslide is also able to be determined. The results show that(1) the affected areas are mainly concentrated at the outfall of the gully and on both sides of the streets.(2) The pore pressure ratio is an important factor affecting the damage range of this debris flow.(3) The increase of the pore pressure ratio in the landslide make the movement distance of debris flow increase significantly. 展开更多
关键词 Izu mountain LANDSLIDE Debris flow Numerical simulation Pore pressure ratio
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Early Holocene High Magnitude Debris Flow Events and Environmental Change as Illustrated by the Moxi Platform, Hengduan Mountains, SW China 被引量:1
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作者 ZHANG Junyan CHENG Genwei LI Yongfei 《Journal of Mountain Science》 SCIE CSCD 2006年第2期125-130,共6页
Thick debris flow deposits in the Hengduan Mountains of southwestern China record landscape instability at the close of the last glaciation and in the early Holocene. The deposits, ranging in thickness from 100 to 200... Thick debris flow deposits in the Hengduan Mountains of southwestern China record landscape instability at the close of the last glaciation and in the early Holocene. The deposits, ranging in thickness from 100 to 200 m, are common and in high magnitude in the valleys of this region. They are products of large debris flows induced by glacier and enabled by the presence of large amount of glacial debris on the landscape. The carbon 14 dating from Moxi Platform indicates that a period of catastrophic debris flows occurred at c. 7 kyr B.P., and was concurrent with other glacial-fluvial fans and terraces which tied to regional climatic oscillations elsewhere in the Himalaya. The comparable events suggest a strong climatic control on earth surface processes for the dynamics, magnitude, and frequency in this region. 展开更多
关键词 Debris flows environment change HOLOCENE Hengduan mountains China
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The Surface Friction and the Flow over Mountain 被引量:1
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作者 伍荣生 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第3期272-278,共7页
The flow over mountain is quite complicated. There are a lot of papers on this problem and a lot of progresses have been made. However, in the most of these papers, just the dynamics contributions of mountain have bee... The flow over mountain is quite complicated. There are a lot of papers on this problem and a lot of progresses have been made. However, in the most of these papers, just the dynamics contributions of mountain have been analysed; the effect of the friction is often neglected. Since the frictional effect is always associated with flow, especially when it flows over the mountain. The study shows that the friction is small in the magnitude but it is not a negligible effect because it changes the features of the flow. In the case of super-or sub-critical flow, there are two extremes: one maximum, one minimum of the fluid surface on the lee-side of the mountain, while in the inviscid fluid, there is just one extreme. The frictional effect should neither be too strong nor too weak to make the situation happened according to the investigation of this paper. 展开更多
关键词 OVER The Surface Friction and the flow over mountain
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Multi-decadal variations in glacier flow velocity and the influencing factors of Urumqi Glacier No.1 in Tianshan Mountains, Northwest China 被引量:2
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作者 WANG Puyu LI Zhongqin +3 位作者 XU Chunhai XING Wucheng ZHOU Ping ZHANG Hui 《Journal of Arid Land》 SCIE CSCD 2017年第6期900-910,共11页
Urumqi Glacier No. 1 is a representative glacier in the inland areas of Central Asia and is the only Chinese reference glacier in the World Glacier Monitoring Service. In this study, we explored multi-decadal variatio... Urumqi Glacier No. 1 is a representative glacier in the inland areas of Central Asia and is the only Chinese reference glacier in the World Glacier Monitoring Service. In this study, we explored multi-decadal variations in the flow velocity of the glacier and the influencing factors based on continuous field observations and path coefficient analysis. Results show that the glacier flow velocity decreased from 5.5 m/a in 1980/1981 to 3.3 m/a in 2010/2011. The annual variation in the direction of glacier flow velocity in the western branch and eastern branch was less than 1°–3°, and the change of glacier flow velocity in the western branch was more dramatic than that in the eastern branch. Glacier flow velocity was influenced by glacier morphology(including glacier area, glacier length, and ice thickness), glacier mass balance and local climate conditions(air temperature and precipitation), the glacier morphology being the leading factor. The long-term flow velocity data set of Urumqi Glacier No. 1 contributes to a better understanding of glacier dynamics within the context of climatic warming. 展开更多
关键词 glacier flow velocity glacier change path coefficient analysis Urumqi Glacier No.1 Chinese Tianshan mountains
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Let the stream flow up to the mountain top Let the Stream Flow Up to the Mountain Top
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作者 程梓晗 张凌 《大学英语》 2006年第12期50-52,共3页
关键词 讲话者 第一个 英语写作 Let the stream flow up to the mountain top Let the Stream flow Up to the mountain Top
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THE ORIGIN AND CHARACTERISTICS OF THE GLACIAL DEBRIS FLOW IN THE DUKU HIGHWAY OF TIANSHAN MOUNTAINS, CHINA
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作者 Xiong Heigang Liu Gengnian +1 位作者 Cui Zhijiu Song Changqing 《Chinese Geographical Science》 SCIE CSCD 1996年第3期282-288,共7页
Debris flow is one of the most serious natural hazards in the TianshanMountains. According to trigger agent, the debris flow can be divided into stormtype which is caused by flood, and glacial type which is caused by ... Debris flow is one of the most serious natural hazards in the TianshanMountains. According to trigger agent, the debris flow can be divided into stormtype which is caused by flood, and glacial type which is caused by flood from meltingof snow and glacier in hot weather. At present, debris flow causes damage mainly totransportation, sometimes to mining and residents in mountainous area. The catastrophic process and the forming condition of the debris flow show regional regularity,therefore, the research of its distribution, processes, and environmental condition isuseful in mitigating the natural hazard. 展开更多
关键词 DEBRIS flow natural HAZARD TIANSHAN mountainS
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Progress on research and mitigation of wind-blown sand risk in Dunhuang Singing Sand Mountain and Crescent Spring Scenic area,China 被引量:1
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作者 BenLi Liu KeCun Zhang +6 位作者 JianJun Qu HaiJiang Li QingHe Niu ZhiShan An YingJun Pang LiHai Tan GenSheng Yang 《Research in Cold and Arid Regions》 CSCD 2023年第3期113-121,共9页
The Singing Sand Mountain and Crescent Spring Scenic Spot in Dunhuang,Northwest China is a world-renowned desert attraction that is also an integral component of the Dunhuang UNESCO Global Geopark.This scenic area und... The Singing Sand Mountain and Crescent Spring Scenic Spot in Dunhuang,Northwest China is a world-renowned desert attraction that is also an integral component of the Dunhuang UNESCO Global Geopark.This scenic area underwent a 30-year transformation,i.e.,from a severe sand risk with spring water threatened by sand burial due to dune deformation,to restoration of the original sand flow field and mitigation of the sand burial problem.The current paper summarizes the research on the intensive monitoring of the dynamic change of star dunes near the spring,observation of wind and sand flow movement,and then restoring the harmonic vibration of the sand particles(singing sand)that were previously silenced.The existing and prospective impacts of anthropogenic and natural forces on the deformation of the sand dunes are investigated by integrated methods,guiding the implementation of mitigating measures with significant ameliorative effects.Contrast to common sand control practices that aim to reduce wind speed and stop blown sands,our research highlights the importance of maintaining the natural wind flow field in stabilizing surrounding dunes.These mitigation measures consist of removing excessive vegetation and newly constructed buildings to recover the original wind flow field and sand transport activity.Such research and mitigation efforts ensure the scientific protection and restoration of the special desert landform,and contribute to the mutual enhancement of the conservation and exploitation of this desert scenic spot and similar sites. 展开更多
关键词 Singing Sand mountain Crescent Spring Wind-blown sand problem Wind flow field Star dune
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级配与拦挡位置对滑坡碎屑流运动影响研究
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作者 韩培锋 李兴凯 +2 位作者 田述军 樊晓一 刘之葵 《安全与环境学报》 CAS CSCD 北大核心 2024年第4期1422-1433,共12页
为了研究不同级配的高位滑坡碎屑流经多级偏转后冲击不同拦挡结构的运动特性以及致灾效应,结合自然地形构建固定坡度和偏转角度均为45°的离散元模型,并利用DEM软件进行数值模拟分析不同拦挡工况和不同级配对碎屑流颗粒运动过程中... 为了研究不同级配的高位滑坡碎屑流经多级偏转后冲击不同拦挡结构的运动特性以及致灾效应,结合自然地形构建固定坡度和偏转角度均为45°的离散元模型,并利用DEM软件进行数值模拟分析不同拦挡工况和不同级配对碎屑流颗粒运动过程中能量耗散、最终堆积形态,以及碎屑流冲击挡板的作用高度的影响,进而建立相关冲击力学模型。研究结果显示:(1)上下均设置挡板的工况能有效减缓碎屑流颗粒的平均动能和势能,且能有效降低颗粒流翻越挡板的数量,并降低颗粒流的最大运动距离从而减小致灾范围;随着颗粒组级配的增大,势能时程曲线分散点出现的时间越晚,颗粒流最终堆积面积中细颗粒组最大,粗颗粒组最小。(2)当滑槽底部反作用力位置取2/3静止堆积体长度时,计算所得碎屑流最大冲击作用高度与模拟试验结果相接近,力学模型计算的冲击作用高度在0.017~0.138 m。在实际工程中,可按研究相似比对此范围进行加强抗冲击防护。(3)由于侧板的切向力和“颗粒分选效应”,大颗粒会主要冲击挡板的中上部,小颗粒主要冲击挡板的下部,并受偏转角影响集中在一侧,因此工程设计可根据实际情况避免在沟道偏转方向的反向建设工程。研究结果可为高位滑坡碎屑流灾害的治理防护提供参考。 展开更多
关键词 安全工程 山地灾害防治 滑坡碎屑流 分级拦挡 离散元法(DEM)
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襄阳王寨南朝墓室惊现“伶伦作律”画像砖之考辨
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作者 刘正国 《南京艺术学院学报(音乐与表演版)》 北大核心 2024年第5期1-10,I0002,共11页
2023年6—9月间,在湖北襄阳王寨墓地的第三次考古发掘中,惊现一种画面为“一人弹琴、一人听声”的南朝墓室画像砖,其内容疑似千古流传的伯牙与子期的知音故事,考古者遂将其命名为“高山流水”,并付诸多种媒体的报道。本文通过对该画像... 2023年6—9月间,在湖北襄阳王寨墓地的第三次考古发掘中,惊现一种画面为“一人弹琴、一人听声”的南朝墓室画像砖,其内容疑似千古流传的伯牙与子期的知音故事,考古者遂将其命名为“高山流水”,并付诸多种媒体的报道。本文通过对该画像砖出土的实物和图像的辨识,揭示其画面的真实主题应是发生在5000年前黄帝时期的“伶伦作律”重大乐律事象。这一题材画像砖的惊世现身,拂去了2000多年来一直笼罩在“伶伦作律”文本载说上的神话迷雾,毋容置疑地破解了伶伦“听凤凰之鸣,以别十二律”其实就是“依琴定律”的千古之谜;其于中华乐律五千年文明的实证,堪称意义重大。 展开更多
关键词 南朝画像砖 高山流水 伶伦比律 田连操张 凤凰之鸣 琴声
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基于多种水文学方法的秦岭北麓典型河流生态流量分析 被引量:1
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作者 李学武 黄领梅 《水电能源科学》 北大核心 2024年第1期10-13,17,共5页
为科学确定秦岭北麓典型河流沣河的生态流量,保障生态环境安全,合理开发秦岭北麓水资源,基于沣河秦渡镇水文站1953~2013年连续实测月径流资料,使用Tennant法、90%保证法、最枯月平均流量法、Tessman法、年内展布法、Texas法、典型水文... 为科学确定秦岭北麓典型河流沣河的生态流量,保障生态环境安全,合理开发秦岭北麓水资源,基于沣河秦渡镇水文站1953~2013年连续实测月径流资料,使用Tennant法、90%保证法、最枯月平均流量法、Tessman法、年内展布法、Texas法、典型水文频率年法及NGPRP法8种水文学方法计算沣河生态流量值。通过分析对比结果表明,Texas法在满足程度、水文节律方面表现较好,最终推荐Texas法作为沣河的生态流量计算方法,并给出生态流量推荐值。研究结果可为秦岭地区水资源的开发利用提供科学依据,对区域河流生态系统健康也具有重要意义。 展开更多
关键词 生态流量 秦岭北麓 沣河 Texas法
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海上退役石油平台造礁的流场效应研究
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作者 张伯涵 张学庆 +2 位作者 郑西来 管瑞 宋晓冉 《海洋工程》 CSCD 北大核心 2024年第1期86-95,共10页
将海上石油平台改建为人工鱼礁是一种理想的退役平台处置方式,流场对人工鱼礁发挥功效起着重要作用,而目前对平台造礁的流场效应仍有待研究。基于埕岛油田退役平台造礁示范工程,构建了渤海埕岛油田海域三维水动力数值模型,在实际海况条... 将海上石油平台改建为人工鱼礁是一种理想的退役平台处置方式,流场对人工鱼礁发挥功效起着重要作用,而目前对平台造礁的流场效应仍有待研究。基于埕岛油田退役平台造礁示范工程,构建了渤海埕岛油田海域三维水动力数值模型,在实际海况条件下定量研究不同规模平台造礁对流场影响效应。结果表明:当布设鱼礁山后,在鱼礁山两侧及上方沿水平来流方向均形成流速增大区域,而迎流面和背流面出现了流速减小区域;与无鱼礁山时相比,随着鱼礁山高度增加和来流速度增大,鱼礁山区域流速变化幅度和变化区域面积逐渐增大,且鱼礁山高度对流速影响范围更大,来流速度则决定流速变化幅度;在垂向上会产生明显的上升流与背涡流,随着水平来流速度增大,鱼礁山高度对垂向流场的影响程度逐渐减小。 展开更多
关键词 平台造礁 数值模拟 人工鱼礁山 流场效应 埕岛油田
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近40 a昆仑山北麓典型河流生态基流时空特征
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作者 胡可可 何建村 +2 位作者 赵健 塔依尔 苏里坦 《长江科学院院报》 CSCD 北大核心 2024年第1期44-51,共8页
生态基流是河流生态系统健康稳定的关键,对于水资源缺乏的干旱区内陆河流尤为重要。以昆仑山北麓克里雅河、尼雅河与车尔臣河3条典型季节性内陆河为研究对象,选取1978—2014年流域水文数据,利用QP法、Tennant法、近10 a最枯月平均流量法... 生态基流是河流生态系统健康稳定的关键,对于水资源缺乏的干旱区内陆河流尤为重要。以昆仑山北麓克里雅河、尼雅河与车尔臣河3条典型季节性内陆河为研究对象,选取1978—2014年流域水文数据,利用QP法、Tennant法、近10 a最枯月平均流量法和Texas法4种水文学方法,计算确定河流生态基流并据此分析其时空分异特征与影响因素。结果表明:Tennant法更适合昆仑山北麓河流生态基流计算。从时间变化来看,3条河生态基流年内最大值均出现在7月份,最小值均出现在1月份;年生态基流最大值均出现在2010年左右,最小值在1980年前后,分别以1.378、0.653、3.066 m^(3)/s·(10 a)^(-1)的速度增加。3条河流生态基流空间分布,春季表现为车尔臣河>克里雅河>尼雅河,夏季和秋季均表现为克里雅河>车尔臣河>尼雅河,且同一河流波动变化明显,不同河流之间变化差异不显著(p>0.05)。影响生态基流年内时空差异的主要因素分别是气温、降水和人类活动,其中以车尔臣河流域气温、降水与生态基流的相关性最强,相关系数r分别为0.876、0.917。考虑生态基流时空分布与流域气候变化特征,综合提出3条河流年内各月生态基流管控目标。研究结果可为昆仑山北麓河流生态保护与水资源管理调度提供参考。 展开更多
关键词 生态基流 时空特征 TENNANT法 管控目标 昆仑山北麓
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兼顾鱼类保护与发电需求的秦岭湑水河观音峡电站段生态修复设计
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作者 侯姝君 刘海龙 《中国园林》 CSCD 北大核心 2024年第1期126-132,共7页
随着中国生态文明建设的推进,自然保护地内的建坝河流生态系统修复逐渐受到重视。秦岭作为生物多样性保护热点地区和中央水塔,其淡水生物多样性保护地位十分重要。针对秦岭湑水河珍稀洄游鱼类保护的目标,探讨了恢复河流连通性的多种方案... 随着中国生态文明建设的推进,自然保护地内的建坝河流生态系统修复逐渐受到重视。秦岭作为生物多样性保护热点地区和中央水塔,其淡水生物多样性保护地位十分重要。针对秦岭湑水河珍稀洄游鱼类保护的目标,探讨了恢复河流连通性的多种方案,借助HEC-RAS软件模拟及结果分析,运用水文学、河流生态学、生态水工学、风景园林学的思路与方法,探讨通过拆除观音峡水库大坝同时保留一定发电功能的方法来恢复自然流淌河流、维护珍稀鱼类的生态过程,并且兼顾发电与社会经济发展的可能性策略。 展开更多
关键词 风景园林 秦岭 生态修复 建坝河流 洄游鱼类 自然流淌河流
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华北土石山区油松生长季夜间液流分配特征
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作者 胡蕾 贾剑波 +3 位作者 闫文德 王一帆 吴瑞乔 陈玉 《林业科学》 EI CAS CSCD 北大核心 2024年第4期91-98,共8页
【目的】通过对油松生长季夜间液流特征和环境驱动因素的研究,揭示夜间液流组分拆分特征,探讨夜间液流的组分与气象因子之间的相关关系,以及茎干补水对气象因子的响应,为华北土石山区水资源和水源涵养林管理决策提供理论依据。【方法】... 【目的】通过对油松生长季夜间液流特征和环境驱动因素的研究,揭示夜间液流组分拆分特征,探讨夜间液流的组分与气象因子之间的相关关系,以及茎干补水对气象因子的响应,为华北土石山区水资源和水源涵养林管理决策提供理论依据。【方法】以华北土石山区的油松作为研究对象,根据径阶大小选取18棵样树,在2014年生长季运用Granier热扩散探针技术(TDP)持续观测夜间液流,结合称重式蒸渗仪和自制微型蒸渗仪来计算蒸腾量,解析夜间液流的去向;并进行夜间液流与土壤含水量、大气温度、湿度及光合有效辐射等气象因子的相关分析,以确定主要驱动因素。【结果】在6—9月典型晴天,夜间液流速率都呈逐渐降低趋势,18:00—24:00的夜间液流速率高于00:00—05:00,夜间液流主要用于对白天失水过多的茎干进行补水,以至于在24:00时油松茎干储水量基本达到饱和,因此,00:00—05:00夜间液流速率趋于稳定;油松夜间液流用于茎干补水的比例(95.34%)显著高于用于夜间蒸腾量的比例(4.66%);油松夜间茎干补水量与饱和水汽压差呈极显著正相关(R^(2)=0.793,P<0.01),而对土壤含水量变化响应不敏感(R^(2)=0.105,P>0.05),表明夜间液流主要受饱和水汽压影响。【结论】华北土石山区的油松生长季夜间液流随着夜间时间的进行呈现逐渐降低的趋势;绝大部分的夜间液流用于夜间茎干补水,在气象因子中,饱和水汽压是驱动夜间茎干补水及夜间液流的重要因子(P<0.01)。 展开更多
关键词 夜间液流 分配特征 茎干补水 夜间蒸腾 华北土石山区
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高原山地环境腹箱式灭火飞机投水数值模拟
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作者 郭曹卓尔 朱培 +1 位作者 邵荃 孙智 《哈尔滨商业大学学报(自然科学版)》 CAS 2024年第5期529-535,共7页
为探究高原山地环境下腹箱式灭火飞机投水着水特性,基于VOF多相流模型构建了飞机投水过程仿真模型,分析地形坡度和海拔高度对地面落水分布的影响,并以投水有效利用率和有效水体覆盖厚度为指标评估其投水效能.结果表明,随山地坡度增加,... 为探究高原山地环境下腹箱式灭火飞机投水着水特性,基于VOF多相流模型构建了飞机投水过程仿真模型,分析地形坡度和海拔高度对地面落水分布的影响,并以投水有效利用率和有效水体覆盖厚度为指标评估其投水效能.结果表明,随山地坡度增加,相同飞行速度下落水地面分布的长度减小而宽度增加,落水区域前端水体分布更密集;随海拔高度增加,相同飞行速度下地面落水分布中后区域更连续,且高原环境下落水地面分布宽度增加但长度变化较小.此外,投水效能普遍随坡度的增加先降低后提高;投水有效利用率在小坡度时随海拔高度增加而提高,其他工况下受海拔高度影响较小,有效水体覆盖厚度普遍随海拔高度增加而降低. 展开更多
关键词 灭火飞机 投水仿真 多相流模型 数值模拟 高原山地环境
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