期刊文献+
共找到28篇文章
< 1 2 >
每页显示 20 50 100
粤北湖子对山铀矿床年代学与矿物化学研究及其对铀成矿的启示 被引量:4
1
作者 肖为 范洪海 +2 位作者 庞雅庆 陈东欢 赖中信 《矿床地质》 CAS CSCD 北大核心 2022年第2期383-402,共20页
湖子对山铀矿床位于粤北下庄铀矿田的中部,研究程度较低,对该矿床成矿时代和矿床成因缺乏必要的约束。文章通过LA-ICP-MS等技术手段,对湖子对山铀矿床开展了沥青铀矿U-Pb年代学及微量元素分析,结合矿石中黄铁矿LA-ICP-MS微量元素及硫同... 湖子对山铀矿床位于粤北下庄铀矿田的中部,研究程度较低,对该矿床成矿时代和矿床成因缺乏必要的约束。文章通过LA-ICP-MS等技术手段,对湖子对山铀矿床开展了沥青铀矿U-Pb年代学及微量元素分析,结合矿石中黄铁矿LA-ICP-MS微量元素及硫同位素分析结果,对该矿床的成矿时代、成矿物质来源及矿床成因展开了讨论。研究表明,沥青铀矿中具有较高的普通铅含量,Tera-Wasserburg图解的投图结果表明其形成于(61.6±3.9)Ma(MSWD=1.4),与区域上部分铀矿床成矿时代一致,代表了华南地区一期重要的区域铀成矿事件。沥青铀矿中普通铅的^(207)Pb/^(206)Pb为0.624,表明成矿物质来源于积累了部分放射性成因铅的富铀源区,普通Pb可能以超显微非结构混入物的形式分布于沥青铀矿中。沥青铀矿LA-ICP-MS微量元素组成与黄铁矿显著不同,以富集W、Bi、Pb、Mo、Sb和亏损Cr、Co、Ni、Ti、As等元素为特征,表明成矿物质可能主要来源于花岗岩。黄铁矿微量元素具有低Co、Ni和富As的特征,表明其中低温热液成因,其Bi和Pb、Sb等元素含量较低,与沥青铀矿显著不同,结合镜下观察结果,认为黄铁矿形成于成矿前。该矿床黄铁矿硫同位素结果与诸广-下庄地区部分铀矿床结果一致,且接近于区域花岗岩硫同位素值,而区别于辉绿岩,表明该区部分铀矿床黄铁矿中的硫主要来源于区域花岗岩。 展开更多
关键词 地球化学 U-PB定年 沥青铀矿 黄铁矿 LA-ICP-MS 湖子对山
下载PDF
《对山书屋墨馀录》刻本考
2
作者 曹鑫 《图书馆杂志》 CSSCI 北大核心 2021年第3期123-129,共7页
相关论著、书目大多认为,《对山书屋墨馀录》主要有清同治九年(1870)湖州醉六堂吴氏刻本、清同治十三年(1874)毛氏甲戌定本两种刻本。然而,醉六堂本并非原刻本(最早版本),仅系翻刻本之一种。清同治九年(1870)上海毛氏亦可居刻本系《对... 相关论著、书目大多认为,《对山书屋墨馀录》主要有清同治九年(1870)湖州醉六堂吴氏刻本、清同治十三年(1874)毛氏甲戌定本两种刻本。然而,醉六堂本并非原刻本(最早版本),仅系翻刻本之一种。清同治九年(1870)上海毛氏亦可居刻本系《对山书屋墨馀录》之原刻本,醉六堂本即据亦可居本翻刻而成。同治十年(1871),杭州杨氏文元堂据亦可居本之后印本再次翻刻;十三年甲戌(1874),毛祥麟据亦可居本之后印本重新删易审定,系较好之本。 展开更多
关键词 刻本 初印本 毛祥麟 上海版刻 对山书屋墨馀录》
下载PDF
《明对山秦腔脸谱》考辨
3
作者 张志峰 《戏剧(中央戏剧学院学报)》 CSSCI 北大核心 2017年第1期74-86,共13页
《明对山秦腔脸谱》是一部伪书,不仅不符合秦腔脸谱演进规律,而且与鹿鹤班大净四斤儿所绘秦腔脸谱、清末赵云汉秦腔脸谱设色、构图如出一辙,有明显的因袭关系。另外,从该谱的传承来看,这套脸谱系富平人杨光越于1913至1914年之间绘制,并... 《明对山秦腔脸谱》是一部伪书,不仅不符合秦腔脸谱演进规律,而且与鹿鹤班大净四斤儿所绘秦腔脸谱、清末赵云汉秦腔脸谱设色、构图如出一辙,有明显的因袭关系。另外,从该谱的传承来看,这套脸谱系富平人杨光越于1913至1914年之间绘制,并非康海所绘。 展开更多
关键词 秦腔 脸谱 康海 对山
原文传递
释包山楚简中的“对”字 被引量:1
4
作者 苏杰 《古汉语研究》 CSSCI 北大核心 2000年第3期35-37,共3页
本文释包山楚简之司法文书简中的“”为“对”字,认为它与睡虎地秦墓竹简中的“诊”字音近义同,是同源字。
关键词 楚简 “对” “诊” 同源字 古代汉字
下载PDF
Comparison between the Medullary Indexes of Hairs from Apodemus orestes and A.draco,with Discussion about the Taxonomic Status of A.orestes 被引量:5
5
作者 吴攀文 周材权 +2 位作者 王艳妮 胡锦矗 张承德 《Zoological Research》 CAS CSCD 北大核心 2004年第6期534-537,共4页
The taxonomic status of long-tailed field mouse (Apodemus orestes) is still uncertain up to now.Some scholars regarded it as a subspecies or a synonym of dragon field mouse (A.draco),while other scholars considered it... The taxonomic status of long-tailed field mouse (Apodemus orestes) is still uncertain up to now.Some scholars regarded it as a subspecies or a synonym of dragon field mouse (A.draco),while other scholars considered it a valid species.In the study,five specimens of adult long-tailed field mouse,dragon field mouse and Chevrier's field mouse (A.chevrieri) (as a contrast) were chosen respectively.After treated,with the eyepiece micrometer in the inverted microscope,we made measurements of the widths of hairs and medullas and then calculated the medullary indexes of straight guard hairs from around the mouth,head,back,abdomen and forelimb of each species.The results indicate that,viewing at each of the five parts and the mixture of the five parts,there are no significant differences between A.orestes and A.draco,Significant differences can be found between A.orestes & A.chevrieri and A.draco & A.chevrieri though.The standpoint that A.orestes was listed as a valid species is not supported by this study. 展开更多
关键词 Apodemus orestes Apodemus draco Medullary index of hair Taxonomic status
下载PDF
Ecological Environment Problems and Countermeasures of Small and Middle-sized Rivers in Shandong Province
6
作者 赵维军 彭淑贞 +3 位作者 燕婷婷 张伟 张莹 宋晓鹏 《Agricultural Science & Technology》 CAS 2016年第10期2369-2372,共4页
Water uses in small and middle-sized rivers, and non-ecological treatment model has deteriorated local environment in Shandong. The research reviewed ecological environment status quo of small and middle rivers and co... Water uses in small and middle-sized rivers, and non-ecological treatment model has deteriorated local environment in Shandong. The research reviewed ecological environment status quo of small and middle rivers and concluded existing problems. Finally, ecological treatments were proposed based on treatments at home and abroad in order to improve eco-environment of rivers and build better Shandong. 展开更多
关键词 ECO-ENVIRONMENT Small and middle-sized rivers Problems and Countermeasures Shandong Province
下载PDF
Turbulence regime near the forest floor of a mixed broad leaved/Korean pine forest in Changbai Mountains 被引量:5
7
作者 张军辉 丁之慧 +2 位作者 韩士杰 邹春静 周玉梅 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期119-122,164,共4页
The measurement and observation for this study were carried out by using a three-dimensional (u, v, w) Sonic anemometer (IAP-SA 485), at Forest Ecosystem Opened Research Station of Changbai Mountains (12828扙 and 4224... The measurement and observation for this study were carried out by using a three-dimensional (u, v, w) Sonic anemometer (IAP-SA 485), at Forest Ecosystem Opened Research Station of Changbai Mountains (12828扙 and 4224?N, Jilin Province, P. R. China) in August 2001. The basic characteristics of turbulence, such as turbulence intensity, atmospheric stability, time scales, and convection state, near the forest floor were analyzed. It is concluded that the airflow near forest floor is characterized by high intermittence and asymmetry, and the active and upward movement takes the leading position. Near forest floor, the vertical turbulence is retained and its time scale and length scale are much less than that of u, v components. The eddy near forest floor shows a flat structure and look like a ’Disk’. Buoyancy plays a leading role in the generation and maintenance of local turbulence 展开更多
关键词 Forest floor Velocity statistics Atmospheric stability Convection states
下载PDF
Investigation on the Rare and Endangered Plants in the Fenhe Source
8
作者 郭春燕 岳建英 +5 位作者 李晋川 王文英 Chun-yan Jian-ying Jin-chuan Wen-ying 《Agricultural Science & Technology》 CAS 2010年第5期112-116,共5页
Fouty-eight species of rare and endanged plants in the Fenhe Source,belong to 21 families 37 genera.There were 1specie of national second-class protected plant and 3 species of national third-class plants;4 species of... Fouty-eight species of rare and endanged plants in the Fenhe Source,belong to 21 families 37 genera.There were 1specie of national second-class protected plant and 3 species of national third-class plants;4 species of first-class protected plants,6 species of second-class protected plants and 14 species of third-class protected plants in Shanxi Province.On the basis of analyzing the endanged reasons,related protection countemeasures were put forward in this article. 展开更多
关键词 Fenhe Source Rare and endanged plants Flora Conservation countemeasura
下载PDF
A survey to the distribution of the Scaly-sided Merganser(Mergus squamatus)in Changbai Mountain range(China side) 被引量:6
9
作者 刘培琦 李枫 +4 位作者 宋慧东 王强 宋玉文 刘玉森 朴正极 《Chinese Birds》 2010年第2期148-155,共8页
In 2008 and 2009,we made continuous and repeated breeding surveys of the Scaly-sided Merganser(Mergus squamatus)in the Changbai Mountain range(China side),using a combination of rubber-boat drifting and walking.Each s... In 2008 and 2009,we made continuous and repeated breeding surveys of the Scaly-sided Merganser(Mergus squamatus)in the Changbai Mountain range(China side),using a combination of rubber-boat drifting and walking.Each survey consisted of a census of breeding pairs in the spring and broods in the summer.A total of 1553 km in length of 17 river stretches were surveyed in four different river systems of the Yalujiang,Songhuajiang,Tumenjiang and Mudanjiang rivers.A total of 1354 individuals of the Scaly-sided Merganser were recorded during the both surveys.The breeding density for all the stretches surveyed over both years averaged 0.26 ± 0.30 pairs per km;the population density in the spring averaged 0.75 ± 0.88 individuals per km.According to our survey results,we estimated that the breeding population in the Changbai Mountain range was about 170 breeding pairs of the Scaly-sided Merganser.Three major breeding sites of this bird were found in the Changbai Mountain range in these surveys. 展开更多
关键词 Scaly-sided Merganser Changbai Mountain range breeding pair BROOD DISTRIBUTION
下载PDF
Vertical patterns in plant diversity and their relations with environmental factors on the southern slope of the Tianshan Mountains(middle section)in Xinjiang(China) 被引量:17
10
作者 LIU Bin 《Journal of Mountain Science》 SCIE CSCD 2017年第4期742-757,共16页
The investigation of distribution patterns of species diversity is significant for successful biodiversity conservation. The spatial patterns of vegetation and different life-forms species diversity along an elevation... The investigation of distribution patterns of species diversity is significant for successful biodiversity conservation. The spatial patterns of vegetation and different life-forms species diversity along an elevation gradient in the middle section of the southern slope of the Tianshan Mountains in Xinjiang, China were explored, using the detrended canonical correspondence analysis (DCCA) and the generalized additive model (GAM) methods based on a field survey of 53 sampling plots. In this work 158 species of seed plants were recorded, including 141 herbaceous, 14 shrub, and 2 tree species, in which the woody plants are very limited. 53 sampling plots were classified into 9 major plant communities. The results indicate that the herb communities were the most sensitive to changes in elevation gradient. The diversity indices of the community as a whole presented bimodal patterns. The peak values for the species diversities were found in the transition region between mountain steppe desert and mountain desert steppe (2,200-2,300m), and in the alpine grassland region (2,900-3,100m), while maximum species diversities were in the areas of intermediate environmental gradient. The main environmental factors on the distribution patterns in plant diversity were the elevation, soft water, total nitroeen, available nitrogen, organic matter, and total salt. The response tendency of the four diversity indices for the whole community to the soil environment was the same as that of the herb layers. 展开更多
关键词 Species diversity Distribution pattern Plant community Soil properties Tianshan Mountains
下载PDF
Influence of the Convection over the South China Sea on the Summer Precipitation of Shandong Province 被引量:3
11
作者 ZHANGSuping LIUQinyu +1 位作者 GONGDianli LIUShijun 《Journal of Ocean University of China》 SCIE CAS 2004年第1期23-32,共10页
The pentad average minimum outgoing longwave radiation (OLR) data over the northern South China Sea (SCS) are selected as indexes to analyze the intensity of the convection connected with the SCS monsoon onset. Statis... The pentad average minimum outgoing longwave radiation (OLR) data over the northern South China Sea (SCS) are selected as indexes to analyze the intensity of the convection connected with the SCS monsoon onset. Statistic analysis demonstrates that the index can account for the intensity of the SCS monsoon about, at least, 75%. A significant negative correlation (confident level over 90%) between Shandong’s summer rainfall and the index is found only in the period of 24-26 pentads and limited to the area above the deeper water basin of the SCS (10°-20°N, 110°-117.5°E). Thus the minimum OLR over the deeper water basin during 24-26 pentads can be used as a valuable predictor for the long lead forecast of the precipitation. The 500 hPa geopotential height data in the Northern Hemisphere for the period from 1951 to 2000 are used in order to characterize the physical mechanisms involved. The composite anomalies of the 500 hPa level allow for the identification and detection of the teleconnection of the East Asia North America (EAP) pattern that is responsible to some extent for the interannual variability of the precipitation of Shandong Province. Besides, the interannual differences of the intraseasonal variations (ISV) of OLR and their northward transmission probably make a contribution to the position of the subtropical high which is vital for the summer rainfall in the province. 展开更多
关键词 convection intensity South China Sea interannual variations summer rainfall Shandong Province OLR
下载PDF
3-D fracture network dynamic simulation based on error analysis in rock mass of dam foundation 被引量:4
12
作者 ZHONG Deng-hua WU Han +2 位作者 WU Bin-ping ZHANG Yi-chi YUE Pan 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第4期919-935,共17页
Accurate 3-D fracture network model for rock mass in dam foundation is of vital importance for stability,grouting and seepage analysis of dam foundation.With the aim of reducing deviation between fracture network mode... Accurate 3-D fracture network model for rock mass in dam foundation is of vital importance for stability,grouting and seepage analysis of dam foundation.With the aim of reducing deviation between fracture network model and measured data,a 3-D fracture network dynamic modeling method based on error analysis was proposed.Firstly,errors of four fracture volume density estimation methods(proposed by ODA,KULATILAKE,MAULDON,and SONG)and that of four fracture size estimation methods(proposed by EINSTEIN,SONG and TONON)were respectively compared,and the optimal methods were determined.Additionally,error index representing the deviation between fracture network model and measured data was established with integrated use of fractal dimension and relative absolute error(RAE).On this basis,the downhill simplex method was used to build the dynamic modeling method,which takes the minimum of error index as objective function and dynamically adjusts the fracture density and size parameters to correct the error index.Finally,the 3-D fracture network model could be obtained which meets the requirements.The proposed method was applied for 3-D fractures simulation in Miao Wei hydropower project in China for feasibility verification and the error index reduced from 2.618 to 0.337. 展开更多
关键词 rock mass of dam foundation 3-D fracture network dynamic simulation fractal dimension error analysis relative absolute error(RAE) downhill simplex method
下载PDF
CONVECTIVE ANOMALIES IN TROPICAL OCEAN AREAS AND LONG-LEAD FORECAST OF SUMMER RAINFALL IN SHANDONG 被引量:2
13
作者 张苏平 胡桂芳 《Journal of Tropical Meteorology》 SCIE 2002年第1期56-62,共7页
This study focuses on deep convection anomalies in tropical regions in winter-spring period and their possible influence on the following summer rainfall in Shandong province. On the basis of monthly precipitation wet... This study focuses on deep convection anomalies in tropical regions in winter-spring period and their possible influence on the following summer rainfall in Shandong province. On the basis of monthly precipitation wet and dry summers in Shandong are defined according to a precipitation index. Then monthly OLR data, observed by NOAA satellites, are used to diagnose the features of deep convection for both wet and dry summers. It is found that negative anomalies seem dominant prior to wet summers, while large areas of positive anomalies appear prior to dry summers in tropical oceans. The differences are remarkable especially in the western, middle and eastern tropical Pacific as well as in the tropical Indian Ocean. Correlative analysis confirms the relations between OLR and precipitation. Subtropical High, which plays an essential role in summer rainfall, is also connected with the deep conviction. Altogether eight EOF-CCA forecast models are established on the basis of the above study. The assessment of the models relies on the gauge observing precipitation in 1997 and 1998. The results show that models using spring OLR data appear to be more practicable than those using winter OLR data, and the models established with OLR in western Pacific and the Indian Ocean perform better than the others. 展开更多
关键词 deep convection tropical oceans summer rainfall Shandong province EOF-CCA
下载PDF
Skulls Symmetry of "White Rasquera" Goat
14
作者 Pere M. Pares-Casanova 《Journal of Life Sciences》 2013年第6期630-634,共5页
Three common categories of bilateral asymmetry have been described: directional asymmetry, antisymmetry, and FA (fluctuating asymmetry). FA is the most subtle of the three types of asymmetry, and differs from the p... Three common categories of bilateral asymmetry have been described: directional asymmetry, antisymmetry, and FA (fluctuating asymmetry). FA is the most subtle of the three types of asymmetry, and differs from the patterns of the others in that paired structures tend to be symmetric in size. The analysis of FA allows to estimate the influence of stress factors on animal development and enables evaluation of resistance to stress. The aim of this work was to estimate the symmetry of skulls of a contemporary pure goat breed, as there is currently no study of FA as an estimate of individual quality for domestic goats. For this purpose, 11 landmarks were digitized in two dimensions from the crania of 24 adult goats (12 males and 12 females) belonging to the "White Rasquera" breed. The skulls showed nearly perfect bilateral symmetry. The low detected values of FA in skulls revealed a weak influence of developmental stress on this goat contemporary population and its strong ability to compensate stress. 展开更多
关键词 CRANIOMETRY fluctuating asymmetry geometric morphometrics morphological variation Procrustes superimposition shape analysis.
下载PDF
Research on Tourism Competitiveness of Chinese Island Counties:Based on Factor and Cluster Analysis
15
作者 Chai Shousheng Long Chunfeng Gao Teng 《Chinese Journal of Population,Resources and Environment》 2012年第4期30-34,共5页
From the perspective of tourism competitiveness,the paper takes 12 island counties of China as the research object,and applies the method of factor analysis to study their competitiveness.The result shows that Putuo a... From the perspective of tourism competitiveness,the paper takes 12 island counties of China as the research object,and applies the method of factor analysis to study their competitiveness.The result shows that Putuo and Dinghai are more competitive while Pingtan and Nan'ao are less competitive.Finally,the 12 island counties are divided into four styles:first-class competitive county (Putuo),seond-class competitive counties (Dinghai,Yuhuan),third-class competitive counties (Chongming,Daishan,Changdao,Changhai and Shengsi),fourth-class competitive counties (Dongshan,Dongtou,Pingtan and Nan'ao) by cluster analysis.The classification of island counties is to clear their relative position,then to promote their development. 展开更多
关键词 COMPETITIVENESS factor analysis cluster analysis is- land county
下载PDF
Seafloor Asymmetry in the Atlantic Ocean
16
作者 S.S. Gao K.H. Liu 《Journal of Ocean University of China》 SCIE CAS 2004年第2期191-194,共4页
Measurements of seafloor asymmetry at about 360 000 pairs of conjugate points along 1250 profiles across the mid-Atlantic Ridge (MAR) provide new constraints on models for the upwelling of the buoyant asthenosphere. T... Measurements of seafloor asymmetry at about 360 000 pairs of conjugate points along 1250 profiles across the mid-Atlantic Ridge (MAR) provide new constraints on models for the upwelling of the buoyant asthenosphere. The sign and amplitude of the asymmetry vary systematically and are functions of the distance between the spreading center and the location of the inferred location of maximum regional buoyancy (LMRB) in the asthenosphere. The LMRB is a smooth line derived from the observed asymmetry and is more centered at the regional topographic high than the spreading center. These observations are best explained by active upwelling of the underlying buoyant asthenosphere rather than by pressure-release melting. 展开更多
关键词 seafloor topography seafloor asymmetry mid-ocean ridges Atlantic Ocean
下载PDF
The influence of environmental variables on distribution patterns of Irano-Turanian forests in Alborz Mountains, Iran 被引量:1
17
作者 Hooman RAVANBAKHSH Alireza MOSHKI 《Journal of Mountain Science》 SCIE CSCD 2016年第8期1375-1386,共12页
Topographic and edaphic variables are the main ecological factor determining species spatial variability on mountainous forests. A field study was performed in central Alborz to investigate how the edaphic and topogra... Topographic and edaphic variables are the main ecological factor determining species spatial variability on mountainous forests. A field study was performed in central Alborz to investigate how the edaphic and topographic parameters can affect the tree and shrub communities. Initially, 27 forest stands were identified and the homogeneous units were separated regarding physiognomy. In each single homogeneous unit, one random sample plot (1000 m^2) and totally 43 plots were established. In each plot, the presence and abundance of all trees and shrubs were recorded and four soil samples were taken from depths of 0-5 and 5-20 cm. Concerning classification results, eight different forest communities were identified. The lowest and highest soil pH values were observed in Malus orientalis and pistacia-Amygdalus communities, respectively. The water saturation percent of pure- and mixed Juniperus excelsa and Rhus coriaria was the highest amongst communities. The clay content was the highest in pure J.excelsa. The 0-5 organic matter and Nitrogen content in mixed J. excelsa were significantly higher than pure J. excelsa and other communities. The CCA (Canonical Correspondence Analysis) altitude, precipitation, pH, results indicated that the EC, SP, clay and CaCO3 are the most important factors determine the distribution of trees and shrub in central Alborz. 展开更多
关键词 Irano-Turanian Mountainouswoodlands Multivariate analysis Species-environment relationship
下载PDF
Spatial and temporal variation of drought index in a typical steep alpine terrain in Hengduan Mountains 被引量:1
18
作者 ZHU Guo-feng YANG Ling +3 位作者 QIN Da-he TONG Hua-li LIU Yuan-feng LI Jia-fang 《Journal of Mountain Science》 SCIE CSCD 2016年第7期1186-1199,共14页
This study describes the spatial and temporal variation of a drought index and makes inferences regarding the environmental factors that influence this variability in the Hengduan Mountains. A drought index is typical... This study describes the spatial and temporal variation of a drought index and makes inferences regarding the environmental factors that influence this variability in the Hengduan Mountains. A drought index is typically used to determine the moisture conditions and the magnitude of water deficiency in a given area. Based on data from 26 meteorological stations over the period 1960-2012, the spatial and temporal variations of the drought index were analyzed using a thin plate smoothing splines method that considered elevation as a covariate. The drought index was estimated based on the potential evapotranspiration(E0) as defined by the Penman Monteith model modified by FAO(1998). The results of the reported analysis showed that the drought index in the Hengduan Mountains has been decreasing since 1960 at a rate of-0.008/a. This represented a progressive shift from the "sub-humid" class, which typified the wider area in the Hengduan Mountains, toward the "humid" class, which appeared in the Hengduan Mountains areas. The drought index was relatively high in the north and low in the south and the variation of the drought index varied with seasons. The drought index showed increasing trends in summer and autumn and it is greater in autumn than in summer, while it showed a decreasing trend in spring and winter. Drought index is inversely proportional to the soil relative humidity and Normalized Difference Vegetation Index(NDVI). 展开更多
关键词 Drought index Normalized Difference Vegetation Index Evapotranspiration Thin plate smoothing splines Hengduan Mountains
下载PDF
Transpiration Rates of Carex Meyeriana in Relation to Micrometerological Factors in a Mountain Valley Wetland
19
作者 XU Huifeng JIN Yanming +2 位作者 DENG Wei XU Kezhang WANG Zhen 《Journal of Mountain Science》 SCIE CSCD 2009年第3期293-298,共6页
In order to reveal transpiration rates of wetland plants and its relationships to micro-meterological factors in a mountain valley wetland, relative humidity, air temperature, leaf temperature, soil temperature, photo... In order to reveal transpiration rates of wetland plants and its relationships to micro-meterological factors in a mountain valley wetland, relative humidity, air temperature, leaf temperature, soil temperature, photo flux density and transpiration rates were measured once two hours in a Carex meyeriana wetland of the Changbai Mountain valley in dry (July) and wet (September) of 2003, respectively. Results showed that the tendency of "decreasing after increasing" was obvious in wet season. However, a relatively stable trend was observed for the transpiration in dry season.. Generally, the photon flux density of Carex meyeriana was higher in wet season than that in dry season. However, the variabilities of leaf temperature, air temperature and relative humidity were similar in both seasons. Higher transpiration rates of Carex meyeriana leaves were observed in July (varied from 40 to 150 mol·m-2·s-1) compared to those (varied from 7 to 14 mol·m-2·s-1) in September. Transpiration rates were significantly correlated with air temperature (P<0.01), leaf temperature (P<0.01), and wind speed (P<0.05), but correlationship between relative humidity and photo flux density was not significant (P<0.05). 展开更多
关键词 Micrometerological factors transpiretion rates Carex meyeriana mountain valley wetland
下载PDF
Strengthening the three-dimensional comprehensive observation system of multi-layer interaction on the Tibetan Plateau to cope with the warming and wetting trend 被引量:1
20
作者 Yaoming Ma Binbin Wang +5 位作者 Xuelong Chen Lei Zhong Zeyong Hu Weiqiang Ma Cunbo Han Maoshan Li 《Atmospheric and Oceanic Science Letters》 CSCD 2022年第4期67-71,共5页
Changes in the water cycle on the Tibetan Plateau(TP)have a significant impact on local agricultural production and livelihoods and its downstream regions.Against the background of widely reported warming and wetting,... Changes in the water cycle on the Tibetan Plateau(TP)have a significant impact on local agricultural production and livelihoods and its downstream regions.Against the background of widely reported warming and wetting,the hydrological cycle has accelerated and the likelihood of extreme weather events and natural disasters occurring(i.e.,snowstorms,floods,landslides,mudslides,and ice avalanches)has also intensified,especially in the highelevation mountainous regions.Thus,an accurate estimation of the intensity and variation of each component of the water cycle is an urgent scientific question for the assessment of plateau environmental changes.Following the transformation and movement of water between the atmosphere,biosphere and hydrosphere,the authors highlight the urgent need to strengthen the three-dimensional comprehensive observation system(including the eddy covariance system;planetary boundary layer tower;profile measurements of temperature,humidity,and wind by microwave radiometers,wind profiler,and radiosonde system;and cloud and precipitation radars)in the TP region and propose a practical implementation plan.The construction of such a three-dimensional observation system is expected to promote the study of environmental changes and natural hazards prevention. 展开更多
关键词 Plateau warming and wetting Hydrological cycle Three-dimensional comprehensive observation system of multi-layer interaction Mountain-disaster response Tibetan Plateau
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部