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Journal of Forestry Research 2016年第4期27卷 879-887页

作者： Guanlong Gao xiaoyou zhang Tengfei Yu Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Thus far, measurements and estimations of actual evapotranspiration（ET） in extremely arid areas are still insufficient. Based on successive observations from June–September 2014, we simulated ET of a Populus euphratica Oliv. forest during the growing season in an extremely arid region of northwest China using the Shuttleworth–Wallace（S–W） model. Simulated ET values were compared to those of the eddy-covariance（EC） method on a 1 h interval. With a root mean square error（RMSE）,relative error（RE） and mean absolute error（MAE） of0.192, 3.100 and 0.165 mm h-1, respectively, model performance was not satisfactory. In particular, on days with strong winds（Sep. 11–13）, deviations between simulated and observed ET values increased to 0.275, 0.878 and0.251 mm h-1, RMSE, RE and MAE respectively. These values were significantly greater than those in other study periods and were most likely owing to sharp increases in wind speed. As a result, there were substantial advective effects, which is not consistent with the assumption of the S–W model that there are no advective effects or mesoscale circulation patterns induced by surface discontinuities.

关键词： Wallace extremely satisfactory northwest absolute season successive insufficient sharp assumption

Comparison of three evapotranspiration models with eddy covariance measurements for a Populus euphratica *** in an arid region of northwestern China

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Journal of Arid Land 2016年第1期8卷 146-156页

作者： GAO Guanlong zhang xiaoyou YU Tengfei LIU Bing Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

The accurate estimation of evapotranspiration (ET) in arid regions is important for improving the water use efficiency of vegetation. Based on successive observations from May to October of 2014, we estimated the ET of a Populus euphratica Oliv. forest during the growing season in an extremely arid region using the PM (Penman-Monteith), SW (Shuttleworth-Wallace) and SSW (an improved canopy transpiration model) models. Estimated ET values were compared with those of the eddy covariance measurements. Results indicated that the actual ET of the P. euphratica forest was always overestimated by the PM model. The accuracy of the SW model was higher than that of the PM model. However, some data were not easily obtained because of the complicated structure of the SW model. The newly proposed SSW model gave the most accurate ET values, and its accuracy was higher at hourly than at daily time scale. In conclusion, the SSW model is more suitable for sparse vegetation system at large scales in extremely arid regions.

关键词： evapotranspiration Penman-Monteith model Shuttleworth-Wallace model SSW model

Comparable water use of two contrasting riparian forests in the lower Heihe River basin, Northwest China

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Journal of Forestry Research 2018年第5期29卷 1215-1224页

作者： Tengfei Yu Qi Feng Jianhua Si xiaoyou zhang Haiyang Xi Chunyan Zhao Alxa Desert Eco-hydrology Experimental Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences Lanzhou 730000 China Key Laboratory of Eco-hydrology of Inland River Basin Chinese Academy of Sciences Lanzhou 730000 China Gansu Hydrology and Water Resources Engineering Research Center Lanzhou 730000 China

Understanding forest ecosystem evapotranspiration（ET） is crucial for water-limited environments,particularly those that lack adequate quantified data such as the lower Heihe River basin of northwest China which is primarily dominated by Tamarix ramosissima *** Populus euphratica ***,we selected the growing season for 2 years （2012 and 2014） of two such forests under similar meteorological conditions to compare ET using the eddy covariance（EC） *** the growing seasons,daily ET of *** ranged from 0.3 to 8.0 mm day^（-1） with a mean of 3.6 mm day^（-1）,and daily ET of *** ranged from 0.9 to 7.9 mm day^（-1） with a mean of 4.6 mm day^（-1） for a total of 548 and 707 mm,*** significantly higher ET of the *** stand was directly linked to high soil evaporation rates under sufficient water availability from *** the soil evaporation was disregarded,water use was comparable to two contrasting riparian forests,a *** forest with a total transpiration of 465 mm and a *** forest with 473 *** analysis demonstrated that climate factors accounted for at least 80% of ET variation in both forest *** conclusion,water use of the riparian forests was low and comparable in this arid region,that suggest the long-term plant adaptation to the local climate and conditions of water availability.

关键词： Eddy covariance Evapotranspiration Heihe River basin Riparian forest

Polybrominated diphenyl ether (PBDE) in blood from children (age 9–12) in Taizhou, China

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Journal of Environmental Sciences 2011年第7期23卷 1199-1204页

作者： xiaoyou zhang Xianli Ruan Minchan Yan Yaxian Zhao Wuji Wei Zhanfen Qin Yongjian Yang Haiming Xu Yan Li Nanjing University of Technology Nanjing 210009 China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China Taizhou Hospital Taizhou 317000 China Tongde Hospital Hangzhou 310012 China Taizhou No. 1 Middle School Taizhou 318000 China

Polybrominated diphenyl ethers （PBDEs） as ubiquitous persistent organic pollutants have attracted much attention in recent years. Exposure to PBDEs could induce a high health risk for children. The aim of this study was to investigate the PBDEs exposure of children （9–12 years） from Taizhou, China. Fifty-eight blood samples were collected in one school in a mountainous area in Taizhou. The concentrations of ∑9PBDEs （sum of BDE-28, -47, -99, -100, -153, -154, -183, -197 and -209） ranged from 2.66 to 33.9 ng/g lipid wet （lw） with a median of 7.22 ng/g lw. These concentrations were lower than those of children in USA, but close to European and Asian general population levels. The results showed that children in Taizhou countryside were at a low level of PBDEs exposure. The predominant congener was BDE-209, followed by BDE-28, -47, -197 and -153. High abundance of BDE-209 was consistent with the pollution background of PBDEs in China characterized by high brominated congeners as main pollutants.

关键词： polybrominated diphenyl ether children blood exposure Taizhou

Progress on Space Medicine in 2008-2010

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空间科学学报 2010年第5期30卷 499-503页

作者： Li Yinghui Liu Zhaoxia zhang xiaoyou Bai Yanqiang Chen Shanguang China Astronaut Research and Training Center Beijing 100094 China

Space Medicine is a special subject to be rising with the development of manned *** China,Space Medicine has achieved great development during the past two *** this paper,the basic research of Space Medicine and its a... 详细信息

关键词：航天医学载人航天飞行基础研究中国

Evapotranspiration of a Populus euphratica Oliv. forest and its controlling factors in the lower Heihe River Basin,Northwest China

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Research in Cold and Arid Regions 2017年第2期9卷 175-182页

作者： TengFei Yu Qi Feng JianHua Si xiaoyou zhang ChunYan Zhao Alax Desert Eco-hydrology Experimental Research Station Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou Gansu 730000 China Key Laboratory of Eco-hydrology of Inland River Basin Chinese Academy of Sciences Lanzhou Gansu 730000 China Gansu Hydrology and Water Resources Engineering Research Center Lanzhou Gansu 730000 China

Evapotranspiration (ET) within an ecosystem is crucial for die water-limited environment that currently lacks adequate quantification in the arid region of Northwest China, mainly covered by phreatophytes, such as the Populus euphratica Oliv. tree and the Tamarix ramosissima Ledeb. shrub species. Accordingly. ET was measured for an entire year using eddy covariance (EC) in P. euphratica stands in the lower Heihe River Basin, Northwest China. During the growing season, the total ET was 850 mm, with a mean of 4.0 mm/d, Which is obviously more than that observed at tree-level and stand level scales, which was likely due to the different level of soil evaporation induced by irrigation via water conveyance. Factors associated with ET fall into either environmental or plant eco-physiological categories. Environmental factors account for at least 79% variation of ET and the linear relationship between ET and the voundwater table (GWT) revealed the potential water use of P. euphratica forests under the non-water stress condition with die GWT less than 3 m deep. Plant eco-physiological parameters, specifically die leaf area 'index (LAI), have direct impact on the seasonal pattern of ET which provides a valuable reference to the wide-area estimates of ET for riparian forests by using LAI. In conclusion, P. euphratica forests have high water use after water conveyance, which may be the result of long-term adapting to local climates and limited water availability.

关键词： evapotranspiration eddy covariance Populus euphratica Oliv. forest Bei he River Basin

Characteristics of the stem sap flux of Populus euphratica in the lower reaches of the Heihe River Basin, Northwest China

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Research in Cold and Arid Regions 2009年第5期1卷 458-466页

作者： xiaoyou zhang JianHua Si Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences lanzhou Gansu 730000 China

Populus euphratica trees are the sole natural perennial riparian woodlands native to the river oases in the lower reaches of Heihe River Basin in northwestern *** study investigated characteristics of the stem sap flux of Populus euphratica and its rela-tionship to environmental factors using the thermal dissipation probe(TDP) *** results showed that(1) daily variation of sap flow of *** on clear days exhibited an obvious unimodal curve;sap flow rates in June,July,August,and September were 13.39,12.07,12.69,and 5.10 L/d,respectively;(2) the average transpiration of the Populus euphratica from June through September amounted to 1,309.84 L;(3) stem sap flow can be affected by a number of environmental factors that,in terms of the influential degree,can be arranged in the descending order of air temperature,soil moisture,relative humidity,total solar radiation,soil temperature,and wind velocity.

关键词： sap flow Populus euphratica heat diffusion method environmental factors

National Report on Space Medicine Progress in 2010—2012

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空间科学学报 2012年第5期32卷 693-703页

作者： LI Yinghui LIU Zhaoxia DING Bai LIU Yue zhang xiaoyou BAI Yanqiang CHEN Shanguang China Astronaut Research and Training Center Beijing 100094

Accompanying the flourishing developments of China's manned spaceflight,space medicine has achieved great development during the past two years in *** this paper,scientific research of space medicine and its applicati... 详细信息

关键词： Space medicine Progress Spaceflight

National Report on Space Medicine Progress in 2014-2016

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空间科学学报 2016年第5期36卷 781-787页

作者： LI Yinghui zhang xiaoyou WAN Yumin DING Bai LIU Zhaoxia LING Shukuan BAI Yanqiang CHEN Shanguang State Key Lab of Space Medicine Fundamentals and Application China Astronaut Research and Training Center

The progress of China Spaceflight makes a great impetus for the development of space *** the developing of China Space Station,the national space medicine has attained great *** this paper,the basic research of Space ... 详细信息

关键词：航天医学中国航天医学发展基础研究空间站

National Report on Space Medicine Progress in 2012–2014

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空间科学学报 2014年第5期34卷 740-746页

作者： LI Yinghui zhang xiaoyou WAN Yumin DING Bai LIU Zhaoxia LING Shukuan BAI Yanqiang CHEN Shanguang LIU Shujuan State Key Laboratory of Space Medicine Fundamentals and Application China Astronaut Research and Training Center

The application of manned spaceflight makes a great impetus on the development of space medicine. With the deep growth of Chinese manned space, our national space medicine has attained great achievements. In this pape... 详细信息

关键词： Spaceflight Space medicine Progress