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Propagation characteristics from meteorological drought to agricultural drought over the Heihe River Basin, Northwest China 被引量:1
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作者 BAI Miao LI Zhanling +2 位作者 HUO Pengying WANG Jiawen LI Zhanjie 《Journal of Arid Land》 SCIE CSCD 2023年第5期523-544,共22页
In the context of global warming,drought events occur frequently.In order to better understanding the process and mechanism of drought occurrence and evolution,scholars have dedicated much attention on drought propaga... In the context of global warming,drought events occur frequently.In order to better understanding the process and mechanism of drought occurrence and evolution,scholars have dedicated much attention on drought propagation,mainly focusing on drought propagation time and propagation probability.However,there are relatively few studies on the sensitivities of drought propagation to seasons and drought levels.Therefore,we took the Heihe River Basin(HRB)of Northwest China as the case study area to quantify the propagation time and propagation probability from meteorological drought to agricultural drought during the period of 1981–2020,and subsequently explore their sensitivities to seasons(irrigation and non-irrigation seasons)and drought levels.The correlation coefficient method and Copula-based interval conditional probability model were employed to determine the drought propagation time and propagation probability.The results determined the average drought propagation time as 8 months in the whole basin,which was reduced by 2 months(i.e.,6 months)on average during the irrigation season and prolonged by 2 months(i.e.,10 months)during the non-irrigation season.Propagation probability was sensitive to both seasons and drought levels,and the sensitivities had noticeable spatial differences in the whole basin.The propagation probability of agricultural drought at different levels generally increased with the meteorological drought levels for the upstream,midstream,and southern downstream regions of the HRB.Lesser agricultural droughts were more likely to be triggered during the irrigation season,while severer agricultural droughts were occurred mostly during the non-irrigation season.The research results are helpful to understand the characteristics of drought propagation and provide a scientific basis for the prevention and control of droughts.This study is of great significance for the rational planning of local water resources and maintaining good ecological environment in the HRB. 展开更多
关键词 meteorological drought agricultural drought drought propagation time drought propagation probability Copula function interval conditional probability heihe river basin
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Impact of land use change on water resource allocation in the middle reaches of the Heihe River Basin in northwestern China 被引量:29
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作者 YanYun NIAN Xin LI +1 位作者 Jian ZHOU XiaoLi HU 《Journal of Arid Land》 SCIE CSCD 2014年第3期273-286,共14页
In recent decades, China has been experiencing rapid economic development, population growth and urbanization. These processes have stressed the shortages of water resources in China, especially in the arid re- gions ... In recent decades, China has been experiencing rapid economic development, population growth and urbanization. These processes have stressed the shortages of water resources in China, especially in the arid re- gions of northwestern China. In order to sustain the expanding cropland, people increased groundwater exploitation in these regions. The purpose of this study was to quantitatively analyze the changes in land use and water resources, and their relationship in the middle reaches of the Heihe River Basin, a typical inland river basin in northwest China. The data of land use change were interpreted using aerial photographs (1965) and Landsat TM images (1986 and 2007). The data of irrigation water volume in the irrigation districts were spatialized in the middle reaches of the Heihe River Basin. The spatial variation of the groundwater depth was interpolated using the geo- statistical method. The results showed that the cultivated cropland area along oasis fringe increased by 15.38% and 43.60% during the periods 1965-1986 and 1986-2007, respectively. Surface water amount for irrigation had almost doubled from 1956 to 2010. The decrease of grassland area mainly occurred at the alluvial fan in front of the Qilian Mountains, with 36.47% during 1965-1986 and 38.56% during 1986-2007, respectively. The groundwater depth in front of the mountain constantly increased from 1986 to 2007. We found that the overuse of surface water and overexploitation of groundwater had direct consequences on the natural environments. We suggests that the efficiency of surface water resources use among different irrigation distdcts needs to be improved, which will significantly ease the conflicts between increasing water demand for irrigation and a shortage of water resources in the middle reaches of the Heihe River Basin. 展开更多
关键词 watershed management land use GROUNDWATER IRRIGATION arid region heihe river basin
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Desertification dynamic and the relative roles of climate change and human activities in desertification in the Heihe River Basin based on NPP 被引量:19
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作者 Wei ZHOU ZhengGuo SUN +2 位作者 JianLong LI ChengCheng GANG ChaoBin ZHANG 《Journal of Arid Land》 SCIE CSCD 2013年第4期465-479,共15页
Relative roles of climate change and human activities in desertification are the hotspot of research on desertification dynamic and its driving mechanism.To overcome the shortcomings of existing studies,this paper sel... Relative roles of climate change and human activities in desertification are the hotspot of research on desertification dynamic and its driving mechanism.To overcome the shortcomings of existing studies,this paper selected net primary productivity (NPP) as an indicator to analyze desertification dynamic and its impact factors.In addition,the change trends of actual NPP,potential NPP and HNPP (human appropriation of NPP,the difference between potential NPP and actual NPP) were used to analyze the desertification dynamic and calculate the relative roles of climate change,human activities and a combination of the two factors in desertification.In this study,the Moderate Resolution Imaging Spectroradiometer (MODIS)-Normalised Difference Vegetation Index (NDVI) and meteorological data were utilized to drive the Carnegie-Ames-Stanford Approach (CASA) model to calculate the actual NPP from 2001 to 2010 in the Heihe River Basin.Potential NPP was estimated using the Thornthwaite Memorial model.Results showed that 61% of the whole basin area underwent land degradation,of which 90.5% was caused by human activities,8.6% by climate change,and 0.9% by a combination of the two factors.On the contrary,1.5% of desertification reversion area was caused by human activities and 90.7% by climate change,the rest 7.8% by a combination of the two factors.Moreover,it was demonstrated that 95.9% of the total actual NPP decrease was induced by human activities,while 69.3% of the total actual NPP increase was caused by climate change.The results revealed that climate change dominated desertification reversion,while human activities dominated desertification expansion.Moreover,the relative roles of both climate change and human activities in desertification possessed great spatial heterogeneity.Additionally,ecological protection policies should be enhanced in the Heihe River Basin to prevent desertification expansion under the condition of climate change. 展开更多
关键词 DESERTIFICATION net primary productivity (NPP) climate change human activities quantitative assessment heihe river basin
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Temporal variations of reference evapotranspiration and its sensitivity to meteorological factors in Heihe River Basin, China 被引量:6
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作者 Jie Zhao Zong-xue Xu +1 位作者 De-peng Zuo Xu-ming Wang 《Water Science and Engineering》 EI CAS CSCD 2015年第1期1-8,共8页
On the basis of daily meteorological data from 15 meteorological stations in the Heihe River Basin (HRB) during the period from 1959 to 2012, long-term trends of reference evapotranspiration (ET0) and key meteorol... On the basis of daily meteorological data from 15 meteorological stations in the Heihe River Basin (HRB) during the period from 1959 to 2012, long-term trends of reference evapotranspiration (ET0) and key meteorological factors that affect ET0 were analyzed using the Mann- Kendall test. The evaporation paradox was also investigated at 15 meteorological stations. In order to explore the contribution of key meteo- rological factors to the temporal variation of ET0, a sensitivity coefficient method was employed in this study. The results show that: (1) mean annual air temperature significantly increased at all 15 meteorological stations, while the mean annual ET0 decreased at most of sites; (2) the evaporation paradox did exist in the HRB, while the evaporation paradox was not continuous in space and time; and (3) relative humidity was the most sensitive meteorological factor with regard to the temporal variation of ET0 in the HRB, followed by wind speed, air temperature, and solar radiation. Air temperature and solar radiation contributed most to the temporal variation of ETo in the upper reaches; solar radiation and wind speed were the determining factors for the temporal variation of ET0 in the middle-lower reaches. 展开更多
关键词 Reference evapotranspiration Evaporation paradox Meteorological factor heihe river basin
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Recent Changes in Precipitation Extremes in the Heihe River Basin,Northwest China 被引量:5
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作者 CHENG Aifang FENG Qi +4 位作者 Guobin FU ZHANG Jiankai LI Zongxing HU Meng WANG Gang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第10期1391-1406,共16页
Changes in rainfall extremes pose a serious and additional threat to water resources planning and management, natural and artificial oasis stability, and sustainable development in the fragile ecosystems of arid inlan... Changes in rainfall extremes pose a serious and additional threat to water resources planning and management, natural and artificial oasis stability, and sustainable development in the fragile ecosystems of arid inland river basins. In this study, the trend and temporal variation of extreme precipitation are analyzed using daily precipitation datasets at 11 stations over the arid inland Heihe River basin in Northwest China from 1960 to 2011. Eight indices of extreme precipitation are studied. The results show statistically significant and large-magnitude increasing and decreasing trends for most indices, primarily in the Qilian Mountains and eastern Hexi Corridor. More frequent and intense rainfall extremes have occurred in the southern part of the desert area than in the northern portion. In general, the temporal variation in precipitation extremes has changed throughout the basin. Wet day precipitation and heavy precipitation days show statistically significant linear increasing trends and step changes in the Qilian Mountains and Hexi Corridor. Consecutive dry days have decreased obviously in the region in most years after approximately the late 1980s, but meanwhile very long dry spells have increased, especially in the Hexi Corridor. The probability density function indicates that very long wet spells have increased in the Qilian Mountains. The East Asian summer monsoon index and western Pacific subtropical high intensity index possess strong and significant negative and positive correlations with rainfall extremes, respectively. Changes in land surface characteristics and the increase in water vapor in the wet season have also contributed to the changes in precipitation extremes over the river basin. 展开更多
关键词 precipitation extremes atmospheric circulation heihe river basin Northwest China
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Impact of climate change and variability on water resources in Heihe River Basin 被引量:6
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作者 NHANGJishi KANGErsi +1 位作者 LANYongchao CHENRensheng 《Journal of Geographical Sciences》 SCIE CSCD 2003年第3期286-292,共7页
Studies indicate that the climate has experienced a dramatic change in the Heihe River Basin with scope of temperature rise reaching 0.5-1.1 o C in the 1990s compared to the mean value of the per... Studies indicate that the climate has experienced a dramatic change in the Heihe River Basin with scope of temperature rise reaching 0.5-1.1 o C in the 1990s compared to the mean value of the period 1960-1990, precipitation increased 18.5 mm in the 1990s compared to the 1950s, and 6.5 mm in the 1990s compared to the mean value of the period 1960-1990, water resources decreased 2.6×10 8 m 3 in the 1990s compared to the 1950s, and 0.4×10 8 m 3 in the 1990s compared to the mean value of the period 1960-1990. These changes have exerted a greater effect on the local environment and socio-economy, and also made the condition worsening in water resources utilizations in the Heihe Rver Basin. 展开更多
关键词 climate change water resources variability heihe river basin of Northwest China
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Groundwater Recharge and Mixing in Arid and Semiarid Regions:Heihe River Basin,Northwest China 被引量:4
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作者 CAO Guoliang ZHENG Chunmiao Craig T.SIMMONS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期971-987,共17页
A sound understanding of groundwater recharged from various sources occurring at different time scales is crucial for water management in arid and semi-arid river basins. Groundwater recharge sources and their geochem... A sound understanding of groundwater recharged from various sources occurring at different time scales is crucial for water management in arid and semi-arid river basins. Groundwater recharge sources and their geochemical evolution are investigated for the Heihe River Basin (HRB) in northwest China on the basis of a comprehensive compilation of geochemical and isotopic data. Geochemical mass- balance modeling indicates that mountain-block recharge accounts for a small fraction (generally less than 5%) of the shallow and deep groundwater sustaining the oasis, whereas infiltration of rivers and irrigation water contribute most of the groundwater recharge. Dedolomitization is the primary process responsible for the changes in groundwater chemical and carbon isotope compositions from the piedmont to the groundwater discharge zone, where the dedolomitization is very likely enhanced by modern agricultural activities affecting the shallow groundwater quality. Analysis of radioactive isotopes suggests that these primary recharge sources occur at two different time scales. Radiocarbon-derived groundwater age profiles indicate a recharge rate of approximately 12 mm/year, which probably occurred during 2000-7000 years B.P., corresponding to the mid-Holocene humid period. The recharge of young groundwater on the tritium-dated time scale is much higher, about 360 mm/year in the oasis region. Infiltration from irrigation canals and irrigation return flow are the primary contributors to the increased young groundwater recharge. This study suggests that groundwater chemistry in the HRB has been influenced by the complex interaction between natural and human-induced geochemical processes and that anthropogenic effects have played a more significant role in terms of both groundwater quantity and quality. 展开更多
关键词 heihe river basin groundwater recharge groundwater mixing isotope hydrology
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Validation of WRF model on simulating forcing data for Heihe River Basin 被引量:10
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作者 XiaoDuo Pan Xin Li 《Research in Cold and Arid Regions》 2011年第4期344-357,共14页
The research of coupling WRF (Weather Research and Forecasting Model) with a land surface model is enhanced to explore the interaction of the atmosphere and land surface; however, regional applicability of WRF model... The research of coupling WRF (Weather Research and Forecasting Model) with a land surface model is enhanced to explore the interaction of the atmosphere and land surface; however, regional applicability of WRF model is questioned. In order to do the validation of WRF model on simulating forcing data for the Heihe River Basin, daily meteorological observation data from 15 stations of CMA (China Meteorological Administration) and hourly meteorological observation data from seven sites of WATER (Watershed Airborne Telemetry Experimental Research) are used to compare with WRF simulations, with a time range of a whole year for 2008. Results show that the average MBE (Mean Bias Error) of daily 2-m surface temperature, surface pressure, 2-m relative humidity and 10-m wind speed were -0.19 ℃, -4.49 hPa, 4.08% and 0.92 m/s, the average RMSE (Root Mean Square Error) of them were 2.11 ℃, 5.37 hPa, 9.55% and 1.73 m/s, and the average R (correlation coefficient) of them were 0.99, 0.98, 0.80 and 0.55, respectively. The average MBE of hourly 2-m surface temperature, surface pressure, 2-m relative humidity, 10-m wind speed, downward shortwave radiation and downward longwave were-0.16 ℃,-6.62 hPa,-5.14%, 0.26 m/s, 33.0 W/m^2 and-6.44 W/m^2, the average RMSE of them were 2.62 ℃, 17.10 hPa, 20.71%, 2.46 m/s, 152.9 W/m^2 and 53.5 W/m^2, and the average R of them were 0.96, 0.97, 0.70, 0.26, 0.91 and 0.60, respectively. Thus, the following conclusions were obtained: (1) regardless of daily or hourly validation, WRF model simulations of 2-m surface temperature, surface pressure and relative humidity are more reliable, especially for 2-m surface air temperature and surface pressure, the values of MBE were small and R were more than 0.96; (2) the WRF simulating downward shortwave radiation was relatively good, the average R between WRF simulation and hourly observation data was above 0.9, and the average R of downward longwave radiation was 0.6; (3) both wind speed and rainfall simulated from WRF model did not agree well with observation data. 展开更多
关键词 forcing data weather research and forecasting model watershed airborne telemetry experimental research heihe river basin
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Tree-ring-based reconstruction of temperature variability(1445–2011) for the upper reaches of the Heihe River Basin, Northwest China 被引量:5
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作者 WANG Yamin FENG Qi KANG Xingcheng 《Journal of Arid Land》 SCIE CSCD 2016年第1期60-76,共17页
Long-term temperature variability has significant effects on runoff into the upper reaches of inland rivers. This paper developed a tree-ring chronology of Qilian juniper (Sabina przewalskii Kom.) from the upper tree-... Long-term temperature variability has significant effects on runoff into the upper reaches of inland rivers. This paper developed a tree-ring chronology of Qilian juniper (Sabina przewalskii Kom.) from the upper tree-line of the middle Qilian Mountains within the upper reaches of Heihe River Basin, Northwest China for a long-term reconstruction of temperature at the study site. In this paper, tree-ring chronology was used to examine climate-growth associations considering local climate data obtained from Qilian Meteorological Station. The results showed that temperatures correlated extremely well with standardized growth indices of trees (r=0.564, P<0.001). Tree-ring chronology was highest correlated with annual mean temperature (r=0.641, P<0.0001). Annual mean temperature which spans the period of 1445–2011 was reconstructed and explained 57.8% of the inter-annual to decadal temperature variance at the regional scale for the period 1961–2011. Spatial correlation patterns revealed that reconstructed temperature data and gridded temperature data had a significant correlation on a regional scale, indicating that the reconstruction represents climatic variations for an extended area surrounding the sampling sites. Analysis of the temperature reconstruction indicated that major cold periods occurred during the periods of 1450s–1480s, 1590s–1770s, 1810s–1890s, 1920s–1940s, and 1960s–1970s. Warm intervals occurred during 1490s–1580s, 1780s–1800s, 1900s–1910s, 1950s, and 1980s to present. The coldest 100-year and decadal periods occurred from 1490s–1580s and 1780s–1800s, respectively, while the warmest 100 years within the studied time period was the 20<sup>th</sup> century. Colder events and intervals coincided with wet or moist conditions in and near the study region. The reconstructed temperature agreed well with other temperature series reconstructed across the surrounding areas, demonstrating that this reconstructed temperature could be used to evaluate regional climate change. Compared to the tree-ring reconstructed temperature from nearby regions and records of glacier fluctuations from the surrounding high mountains, this reconstruction was reliable, and could aid in the evaluation of regional climate variability. Spectral analyses suggested that the reconstructed annual mean temperature variation may be related to large-scale atmospheric–oceanic variability such as the solar activity, Pacific Decadal Oscillation (PDO) and El Ni?o–Southern Oscillation (ENSO). 展开更多
关键词 TREE-RING climatic response temperature reconstruction upper reaches of heihe river basin
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Impacts of land use changes on groundwater resources in the Heihe River Basin 被引量:4
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作者 WANG Genxu YANG Lingyuan +1 位作者 CHEN Ling Jumpei Kubota 《Journal of Geographical Sciences》 SCIE CSCD 2005年第4期405-414,共10页
Land use and land cover changes have a great impact on the regional hydrological process. Based on three periods of remote sensing data from the 1960s and the long-term observed data of groundwater from the 1980s, the... Land use and land cover changes have a great impact on the regional hydrological process. Based on three periods of remote sensing data from the 1960s and the long-term observed data of groundwater from the 1980s, the impacts of land use changes on the groundwater system in the middle reach of Heihe River Basin in recent three decades are analyzed by the perspective of groundwater recharge and discharge system. The results indicate that with the different intensities of land use changes, the impacts on the groundwater recharge were 2.602 × 10^8 m^3/a in the former 15 years (1969-1985) and 0.218 × 10^8 m^3/a in the latter 15 years (1986-2000), and the impacts on the groundwater discharge were 2.035 × 10^8 m^3/a and 4.91 × 10^8 m^3/a respectively. When the groundwater exploitation was in a reasonable range less than 3.0 × 10^8 m^3/a, the land use changes could control the changes of regional groundwater resources. Influenced by the land use changes and the large-scale exploitation in the recent decade, the groundwater resources present apparently regional differences in Zhangye region. Realizing the impact of land use changes on groundwater system and the characteristics of spatial-temporal variations of regional groundwater resources would be very important for reasonably utilizing and managing water and soil resources. 展开更多
关键词 land use change inland fiver groundwater system heihe river basin
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Spatiotemporal variations of maximum seasonal freeze depth in 1950s–2007 over the Heihe River Basin, Northwest China 被引量:3
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作者 QingFeng Wang TingJun Zhang 《Research in Cold and Arid Regions》 CSCD 2014年第3期209-218,共10页
Investigation on spatiotemporal variations of maximum seasonal freeze depth (MSFD) over the Heihe River Basin is of great importance for systematic understanding of regional climate and environmental change, ecologi... Investigation on spatiotemporal variations of maximum seasonal freeze depth (MSFD) over the Heihe River Basin is of great importance for systematic understanding of regional climate and environmental change, ecological-hydrological processes, water resources assessment, construction and resource development. Based on soil and air temperatures at the meteorological stations of the China Meteorological Administration (CMA) over the Heihe River Basin, MSFDs time series are structured into a composite time series over the 1960-2007 period. Evaluating the averaged MSFD time series for 1960 2007 reveals a statistically significant trend of 4.0 cm/decade or a net change of-19.2 cm for the 48-year period over the basin. The MSFD had significantly negative correlation with mean annual air temperature (MAAT), winter air temperature, mean annual ground surface temperature (MAGST), degree days of thawing for the air (DDTa) as well as for the surface (DDTs), and degree days of freezing for the surface (DDFs). While there was significantly positive correlation between DDF,. and MSFD time series, MSFD was deeper and changed greatly in the Heihe River source area. It was shallower in the east-central basin and gradually deepened in other sections of the basin. The MSFD distribution pattern in 2003-2005 is consistent with that of averaged degree days of freezing for air (DDFa) in 1960-2007. However, the maximum of MSFD may not be accurate, because there is no long term observation data in the deep seasonally frozen ground regions near the lower boundary of permafrost. With increasing elevation, averaged DDFa increased at a rate of 51.6 ℃-day/100m, therefore, the MSFG and the date reaching MSFG became deeper and later, respectively. 展开更多
关键词 spatiotemporal variations MSFD potential driving variables seasonally frozen ground heihe river basin
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Integrated hydrologic modeling in the inland Heihe River Basin, Northwest China 被引量:2
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作者 YanBo Zhao ZhuoTong Nan +3 位作者 Hao Chen Xin Li Ramasamy Jayakumar WenJun Yu 《Research in Cold and Arid Regions》 CSCD 2013年第1期35-50,共16页
As a typical inland river basin in arid Northwest China, having distinct hydrological characteristics and severe and repre- sentative water problems, the Heihe River Basin (HRB) has attracted considerable research i... As a typical inland river basin in arid Northwest China, having distinct hydrological characteristics and severe and repre- sentative water problems, the Heihe River Basin (HRB) has attracted considerable research interest worldwide and in 2007 became a pilot basin of the G-WADI network of UNESCO/1HR Many research programs have been conducted in the HRB since the 1980s, producing rich knowledge and data about the basin, which will be very helpful to further studies. This paper reviews research efforts related to hydrologic modeling and ongoing model integration studies performed in the HRB in re- cent years. Recently, an observation network covering the whole area and a Web-based data-sharing system have been estab- lished which can greatly improve data acquisition. This paper tabulates modeling activities in past years, including model ap- plications, model modifications and enhancements, and model coupling efforts. Also described is a preliminary modeling in- tegration tool designed to quickly build new models, which has been developed for hydrologic modeling purposes. Challeng- es and issues confronted in current studies are discussed, pointing toward key research directions in the future. 展开更多
关键词 hydrologic modeling water resources management heihe river basin
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Comparable water use of two contrasting riparian forests in the lower Heihe River basin, Northwest China 被引量:1
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作者 Tengfei Yu Qi Feng +3 位作者 Jianhua Si Xiaoyou Zhang Haiyang Xi Chunyan Zhao 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1215-1224,共10页
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 p... 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 Ledeb.and Populus euphratica Oliv.forests.Accordingly,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) technique.During the growing seasons,daily ET of T.ramosissima ranged from 0.3 to 8.0 mm day^(-1) with a mean of 3.6 mm day^(-1),and daily ET of P.euphratica 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,respectively.The significantly higher ET of the P.euphratica stand was directly linked to high soil evaporation rates under sufficient water availability from irrigation.When the soil evaporation was disregarded,water use was comparable to two contrasting riparian forests,a P.euphratica forest with a total transpiration of 465 mm and a T.ramosissima forest with 473 mm.Regression analysis demonstrated that climate factors accounted for at least 80% of ET variation in both forest types.In 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. 展开更多
关键词 Eddy covariance EVAPOTRANSPIRATION heihe river basin Riparian forest
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Recent changes in ground surface thermal regimes in the context of air temperature warming over the Heihe River Basin, China 被引量:1
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作者 QingFeng Wang TingJun Zhang +1 位作者 XiaoQing Peng Bin Cao 《Research in Cold and Arid Regions》 CSCD 2014年第4期273-281,共9页
Changes in ground surface thermal regimes play a vital role in surface and subsurface hydrology, ecosystem diversity and productivity, and global thermal, water and carbon budgets as well as climate change. Estimating... Changes in ground surface thermal regimes play a vital role in surface and subsurface hydrology, ecosystem diversity and productivity, and global thermal, water and carbon budgets as well as climate change. Estimating spring, summer, autumn and winter air temperatures and mean annual air temperature(MAAT) from 1960 through 2008 over the Heihe River Basin reveals a statistically significant trend of 0.31 °C/decade, 0.28 °C/decade, 0.37 °C/decade, 0.50 °C/decade, and 0.37 °C /decade, respectively. The averaged time series of mean annual ground surface temperature(MAGST) and maximum annual ground surface temperature(MaxAGST) for 1972–2006 over the basin indicates a statistically significant trend of 0.58 °C/decade and 1.27 °C/decade, respectively. The minimum annual ground surface temperature(MinAGST) in the same period remains unchanged as a whole. Estimating surface freezing/thawing index as well as the ratio of freezing index to thawing index(RFT) in the period between 1959 and 2006 over the basin indicates a statistically significant trend of-42.5 °C-day/decade, 85.4 °C-day/decade and-0.018/decade, respectively. 展开更多
关键词 air temperature ground surface temperature freezing index thawing index tendency rate heihe river basin
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Accuracy evaluation of two precipitation datasets over upper reach of Heihe River Basin, northwestern China 被引量:1
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作者 SiWei He ZhuoTong Nan YuTing Hou 《Research in Cold and Arid Regions》 CSCD 2015年第2期157-169,共13页
As an important forcing data for hydrologic models, precipitation has significant effects on model simulation. The China Meteorological Forcing Dataset (ITP) and Global Land Data Assimilation System (GLDAS) precip... As an important forcing data for hydrologic models, precipitation has significant effects on model simulation. The China Meteorological Forcing Dataset (ITP) and Global Land Data Assimilation System (GLDAS) precipitation data are the two commonly used data sources in the Heihe River Basin (HRB). This paper focused on evaluating the accuracy of these two precipitation datasets. A set of metrics were developed to characterize the trend, magnitude, annual allocation, event matching, frequency, and spatial distribution of the two datasets. Meanwhile, such accuracy evaluation was performed at various scales, i.e., daily, monthly, and yearly. By comparing with observations, this study concluded that: first, both ITP and GLDAS precipitation data well represented the trends at corresponding sites, and GLDAS underestimated precipita- tion in most regions except the east tributary headwater region; second, unusual annual precipitation distribution was observed in both datasets with overestimation of precipitation in May through September and GLDAS appeared to be much severe; third, the ITP data seriously over-predicted the precipitation events; fourth, the ITP data have better spatial distribution than GLDAS in the upper reach area of HRB. Overall, we recommended ITP precipitation data for the land surface study in the uooer reach of HRB. 展开更多
关键词 PRECIPITATION heihe river basin (HRB) accuracy evaluation
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Research on the Influence of Land Use Changing on Non-point Source Pollution in Heihe River Basin 被引量:1
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作者 Y.L. Xu S.J. Wang Y.M. Ni 《Journal of Environmental Science and Engineering》 2010年第5期72-77,共6页
Based on the exploring of SWAT model suitability in Hei River Basin, this paper analyze quantitatively and compare non-point source pollution loads occurred under different land use scene. At last, the following concl... Based on the exploring of SWAT model suitability in Hei River Basin, this paper analyze quantitatively and compare non-point source pollution loads occurred under different land use scene. At last, the following conclusion can be attained: (1) Land use change exerts tremendous influence on non-point source pollution. Since forest land can save water and reduce soil loss, which decreases greatly the source of non-point source pollution; (2) Strengthening land management and promoting reasonable land use, especially the over 15 degree slope farmland, will be the effective measure to control non-point source pollution and protect the quality of water in the Hei River basin; (3) The best land use situation in Hei River basin should be like the following modes: complying with national water source protection policy, gradual evacuation of river basin population, returning all the sloping farmland which is above 15 degree to forest land, allowing the existence of few farming land below 15 slope degree on the premise that the drinking water quality standard is reached, no unused land, good vegetation covering situation. At then, total nitrogen load is 13.25 kg, total phosphate load is 3.29 kg, which means it will not contaminate 展开更多
关键词 Non-point source pollution land use changing INFLUENCE heihe river basin.
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Energy Balance of Irrigated Intercropping Field in the Middle Reaches of Heihe River Basin
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作者 WU Jinkui DING Yongjian +3 位作者 WANG Genxu SHEN Yongping Yusuke YAMAZAKI Jumpei KUBOTA 《Chinese Geographical Science》 SCIE CSCD 2006年第3期243-248,共6页
Based on the experiments conducted in an irrigated intercropping field in Zhangye Oasis in the middle reaches of Heihe River basin in 2004, the characteristics of radiation budget are analyzed. Furthermore, energy bal... Based on the experiments conducted in an irrigated intercropping field in Zhangye Oasis in the middle reaches of Heihe River basin in 2004, the characteristics of radiation budget are analyzed. Furthermore, energy balance is cal- culated by using Bowen-Ratio Energy Balance (BREB) method. The results show that the ratio of the absorbed radiation to the incoming short radiation in intercropping crop canopy-soil system is increasing with growing stages, from 0.81 in the initial growing stage (IGS) to 0.86 in the late growing stage (LGS). The net radiation, which is smaller in IGS, in- creases rapidly in the first period of the middle growing stage (MGS) and reaches the maximum value in the second period of MGS. It then somewhat decreases in LGS. The ratio of net radiation to total radiation has a similar trend with the net radiation. In the whole growing stages, latent heat flux, which takes up 70% or so of the net radiation, is the dominant item in energy balance. Sensible heat flux shares 20% of the net radiation and soil heat flux has a percentage of 10%. The characteristics of heat balance vary distinctly in different growing stages. In IGS, the ratios of latent heat flux, sensible heat flux and soil heat flux to net radiation are 44.5%, 23.8% and 31.7% respectively. In MGS, with the in- creasing of latent heat flux and the decreasing of sensible heat flux and soil heat flux, the ratios turn into 84.4%, 6.3% and 9.3%. In LGS, the soil heat flux maintains 0W/m2 or so, and latent heat flux and sensible heat flux take up 61.4% and 38.6% respectively. The energy balance also shows an obvious daily variation characteristic. 展开更多
关键词 radiation budget energy balance intercropping field heihe river basin
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Temporal variations of CO_2 concentration near land surface and its response to meteorological variables in Heihe River Basin, northwest China
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作者 CHEN Ren-sheng KANG Er-si JI Xi-bin YANG Jian-ping ZHANG Zhi-hui YANG Yong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第4期708-715,共8页
Atmospheric CO2 concentration (CC) near land surface and meteorological variables have been measured at four sites, named Yeniugou (alpine meadow and permafrost), Xishui (mountainous forest), Linze (oasis edge... Atmospheric CO2 concentration (CC) near land surface and meteorological variables have been measured at four sites, named Yeniugou (alpine meadow and permafrost), Xishui (mountainous forest), Linze (oasis edge) and Ejina (lower desert), respectively, in Heihe River Basin, northwest China. The results showed that, the half hourly CC at night was larger than in daytime, and the daily averaged CC was the largest in winter. The averaged CC of 932 d at the Linze was about 418 ppm, was about 366 ppm in the 762 d at the Ejina. In the same period from September 23 to November 9, 2004, the averaged CC was about 625,334, 436 and 353 ppm, at Yeniugou, Xishui, Linze and Ejina, respectively. The linear relationship between daily averaged CC and air temperature T was negative, between CC and relative humidity (RH) was positive. The linear CC-atmospheric pressure (A P) relationship was negative at the Linze and Yeniugou, was positive at the Ejina. The relationship between CC and global radiation R was exponent, and soil temperature Ts was negative linear, and soil water content was complex. The correlation between CC and wind speed was not existent. Using meteorological variables together to simulate CC, could give good results. 展开更多
关键词 CO2 concentration meteorological variables heihe river basin
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Water accounting for conjunctive groundwater and surface water irrigation sources: A case study in the middle Heihe River Basin of arid northwestern China
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作者 XueXiang Chang Bing Liu +1 位作者 Hu Liu ShouBo Li 《Research in Cold and Arid Regions》 CSCD 2015年第6期687-701,共15页
Oases in arid northwestern China play a significant role in the region's economic stability and development. Overex- ploitation of the region's water resources has led to serious environmental consequences. In oases... Oases in arid northwestern China play a significant role in the region's economic stability and development. Overex- ploitation of the region's water resources has led to serious environmental consequences. In oases, irrigated agriculture is the primary consumer of water, but water shortages resulting from dramatically growing human needs have become a bottleneck for regional sustainable development, making effective management of the limited available water critical. Effective strategies must be formulated to increase agricultural productivity while reducing its environmental impacts. To support the development of such strategies, water use patterns were analyzed during the 2007 and 2008 growing seasons, from May to early October, to identify opportunities for improving water management using the Mold- en-Sakthivadivel water-accounting method, which combines groundwater and surface water into a single domain and can provide a good estimate of the uses, depletion, and productivity of water in a water basin context. The study area lies in Linze County, Gansu Province, China. In the study area, the inflow water resources consist of irrigation, precipita- tion, and soil water, which accounted for 89.3%, 8.9%, and 1.8% of the total in 2007, and 89.3%, 4.8%, and 5.9% in 2008, respectively. The irrigation depends heavily on groundwater, which accounted for 82.1% and 83.6% of the total irrigation water in 2007 and 2008, respectively. In 2007 and 2008, deep percolation accounted for 50.1% and 47.9% of the water outflow, respectively, with corresponding depleted fractions of 0.51 and 0.55, respectively. For the irrigation district as a whole, the water productivity was only 1.37 CNY/m^3. To significantly increase crop water productivity and prevent depletion of the region's groundwater aquifer, it will be necessary to reduce the amount of water used for ir- rigation. Several water-saving agricultural practices are discussed and recommended. 展开更多
关键词 water accounting water irrigation sources water management water productivity middle heihe river basin northwestern China
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An estimation of groundwater storage variations from GRACE gravity satellites in the Heihe River Basin, northwestern China
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作者 YanPing Cao ZhuoTong Nan XingLin Hu 《Research in Cold and Arid Regions》 CSCD 2014年第6期577-586,共10页
There are only limited surface water resources available in the Heihe River Basin (HRB), a typical inland river basin in the arid region of northwestern China, where groundwater overexploitation is a serious problem... There are only limited surface water resources available in the Heihe River Basin (HRB), a typical inland river basin in the arid region of northwestern China, where groundwater overexploitation is a serious problem. Groundwater has become one of main resources of fresh water in the HRB. In this paper, temporal and spatial variations of groundwater in the HRB are estimated by the Gravity Recovery and Climate Experiment (GRACE) satellites. Our analysis shows that groundwater storage in the HRB reaches its highest in the summer of 2005, and then begins to decline in the following years and reaches steady status in 2008. Spatially, groundwater shows a decline in the upper HRB in the first two years and a slight increase in the following years, while this phenomenon is reversed in the middle HRB where groundwater slightly increases in 2005 and then declines in the following three years. In the lower HRB, GRACE detects a continual increase in the full six-year period. This approach is proven successful when employed in the HRB and thus offers a new insight into monitoring groundwater variations in a river basin with limited or even without any observed data. 展开更多
关键词 GRACE gravity satellites GROUNDWATER heihe river basin terrestrial water storage
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