Relationship of underground water level and climate in Northwest China’s inland basins under the global climate change:Taking the Golmud River Catchment as an example

To identify the response of groundwater level variation to global climate change in Northwest China’s inland basins,the Golmud River Catchment was chosen as a case in this paper.Approaches of time series analysis and correlation analysis were adopted to investigate the variation of groundwater level influenced by global climate change from 1977 to 2017.Results show that the temperature in the Golmud River Catchment rose 0.57℃ every 10 years.It is highly positive correlated with global climate temperature,with a correlation coefficient,0.87.The frequency and intensity of extreme precipitation were both increased.Generally,groundwater levels increased from 1977 to 2017 in all phreatic and confined aquifers and the fluctuation became more violent.Most importantly,extreme precipitation led to the fact that groundwater level rises sharply,which induced city waterlogging.However,no direct evidence shows that normal precipitation triggered groundwater level rise,and the correlation coefficients between precipitation data from Golmud meteorological station located in the Gobi Desert and groundwater level data of five observation wells are 0.13,0.02,−0.11,0.04,and−0.03,respectively.This phenomenon could be explained as that the main recharge source of groundwater is river leakage in the alluvial-pluvial Gobi plain because of the high total head of river water and goodness hydraulic conductivity of the vadose zone.Data analysis shows that glacier melting aggravated because of local temperature increased.As a result,runoff caused groundwater levels to ascend from 1977 to 2017.Correlation coefficients of two groundwater wells observation data and runoff of Golmud River are 0.80 and 0.68.The research results will contribute to handling the negative effects of climate change on groundwater for Northwestern China.

Numerical simulation of response of groundwater flow system in inland basin to density changes

The developmental characteristics of groundwater flow system are not only controlled by formation lithology and groundwater recharge conditions,but also influenced by the physical properties of fluids.Numerical simulation is an effective way to study groundwater flow system.In this paper,the ideal model is generalized according to the fundamental characteristics of groundwater system in inland basins of Western China.The simulation method of variable density flow on the development of groundwater system in inland basins is established by using EOS9 module in TOUGHREACT numerical simulation software.In accordance with the groundwater streamline,the groundwater flow system is divided into three levels,which are regional groundwater flow system,intermediate groundwater flow system and local groundwater flow system.Based on the calculation of the renewal rate of groundwater,the analysis shows that the increase of fluid density in the central part of the basin will restrain the development of regional groundwater flow system,resulting in a decrease of the circulation rate from 32.28% to 17.62% and a certain enhancement to the local groundwater flow system,which increased from 37.29% to 51.94%.

A paleo-hydrological simulation experiment and its verification in an inland basin

Hydrological circulation,as the most basic material cycle and active natural phenomenon on earth,exerts a significant in fluence on climate change.The mid-Holocene is an important period to better understand modern environmental change;however,little research has focused on its quantitative simulation of paleo-hydrological process.In this research,we first collected chronological evidence and sediment records from six Holocene sedimentary sections in the Shiyang River Ba sin to reconstruct the mid-Holocene environment and terminal paleo-lake area.Secondly,we comprehensively analyzed modern pollen combinations and their propagation characteristics in surface soil,air,river and lacustrine sediments in the Shiyang River Basin,and combined the pollen records,as well as quantitatively reconstructed the millennial-scale vegeta tion zones.Finally,based on the land-cover adjustment results during the mid-Holocene,we successfully used the Soil and Water Assessment Tool(SWAT)model,a modern distributed hydrological watershed model,to simulate mid-Holocene runoff in the basin.Results show that the reconstructed climate in the basin was warmer and moister than that in recent times.Vegetation types in the mid-Holocene mainly consisted of sub-alpine shrub distributed between 2,550 m and 2,750 m,forest at an elevation of 2,550 2,750 m,steppe at an elevation of 1,550 2,150 m and desert steppe below 1,550 m.The up stream,midstream,downstream and average annual runoff of the mid-Holocene in the basin were 16.76×10^8 m^3,22.86×10^8 m^3,9.00×10^8 m^3 and 16.20×10^8 m^3 respectively,compared to 15.61×10^8 m^3 of modern annual runoff.Also,the area of terminal paleo-lake in the mid-Holocene was 628 km^2.Thus,this study provides a new quantitative method for paleo-hy drological simulation.

Mutual optimization of water utilization structure and industrial structure in arid inland river basins of Northwest China

Water is a key restricting factor of the economic development and eco-environmental protection in arid inland river basins of Northwest China. Although water supplies are short, the water utilization structure and the corresponding industrial structure are unbalanced. We constructed a System Dynamic Model for mutual optimization based on the mechanism of their interaction. This model is applied to the Heihe River Basin where the share of limited water resources among ecosystem, production and human living is optimized. Results show that, by mutual optimization, the water utilization structure and the industrial structures fit in with each other. And the relationships between the upper, middle and lower reaches of the Heihe River Basin can be harmonized. Mutual benefits of ecology, society and economy can be reached, and a sustainable ecology-production-living system can be obtained. This study gives a new insight and method for the sustainable utilization of water resources in arid inland river basins.

Simulation of hydrological processes of mountainous watersheds in inland river basins: taking the Heihe Mainstream River as an example

The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the mountainous watershed of the Heihe Mainstream River as a study area to simulate the hydrological processes of mountainous watersheds in inland river basins by using the soil and water assessment tool(SWAT)model.SWAT simulation results show that both the Nash–Sutcliffe efficiency and the determination coefficient values of the calibration period(January 1995 to December 2002)and validation period(January 2002 to December 2009)are higher than 0.90,and the percent bias is controlled within±5%,indicating that the simulation results are satisfactory.According to the SWAT performance,we discussed the yearly and monthly variation trends of the mountainous runoff and the runoff components.The results show that from 1996 to 2009,an indistinctive rising trend was observed for the yearly mountainous runoff,which is mainly recharged by lateral flow,and followed by shallow groundwater runoff and surface runoff.The monthly variation demonstrates that the mountainous runoff decreases slightly from May to July,contrary to other months.The mountainous runoff is mainly recharged by shallow groundwater runoff in January,February,and from October to December,by surface runoff in March and April,and by lateral flow from May to September.

SUSTAINABLE EXPLOITATION AND UTILIZATION OF WATER RESOURCES IN THE INLAND RIVERBASIN OF ARID NORTHWEST CHINA

Calculated in terms of surface runoff plus irrepeated groundwater, there is about 8. 67 ×1010m3 of total available water resources in the inland river basins of arid Northwest China. Water resources is the decisive factor for survival of oases and human being. But there have arisen several aspects of Serious eco-environment problems resulted from irrational exploitation and utilization. From now on, the development and utilization of water not only requires to promote regional economy, but also needs to protect and improve the environment based on their potential. Sustainable utilization needs to broaden new sources and saving water at first. Then three measures are recommended.

Study of temperature and precipitation change in upstream mountain area of the Hexi inland river basin since 1960s

All rivers in the Hexi inland region of Gansu Province, China, originate from the northern slope of the Qilian Mountains. They are located in the southern portion of the region and respectively belong to the three large river systems from east to west, the Shiyang, Heihe and Shule river basins. These rivers are supplied by precipitation, snowmelt and ice-melt runoff from the Qilian Mountain area. Therefore, changes of precipitation and temperature in the upstream watersheds of these rivers have an important effect on changes of mountainous runoff and reasonable utilization of water resources in this region. For this reason, the Qilian Mountain area, upstream watersheds and runoff forming areas of these rivers are chosen as the study area. The change characteristics and variation trend of temperature and precipitation in this area under the backdrop of global warming axe analyzed based on observa- tional data of relational weather and hydrologic stations in the area. Results show that temperatures in the upriver mountain areas of these three large river basins have been increasing, although the increasing degree is differentially affected by global warming. The rising extent of annual and seasonal temperatures in the upstream mountain area of the Shule river basin located in the west- em Qilian Mountains, were all largest over the past 50 years. Precipitation in the upstream mountain areas of Hexi region＇ three river basins located respectively in the western, middle and eastern Qilian Mountains have been presenting an increasing trend to varying degrees as a whole for more than 50 years. This means that climate in the upstream mountain areas of Hexi region＇ three river basins are becoming increasingly warmer and moister over the past 50 years, which will be very good for the ecological en- vironment and agricultural production in the region.

Hydrological and water cycle processes of inland river basins in the arid region of Northwest China

The increasing shortage in water resources is a key factor affecting sustainable socio-economic development in the arid region of Northwest China(ARNC). Water shortages also affect the stability of the region's oasis ecosystem. This paper summarizes the hydrological processes and water cycle of inland river basins in the ARNC, focusing on the following aspects: the spatial-temporal features of water resources(including air water vapor resources, runoff, and glacial meltwater) and their driving forces; the characteristics of streamflow composition in the inland river basins; the characteristics and main controlling factors of baseflow in the inland rivers; and anticipated future changes in hydrological processes and water resources. The results indicate that:(1) although the runoff in most inland rivers in the ARNC showed a significant increasing trend, both the glaciated area and glacial ice reserves have been reduced in the mountains;(2) snow melt and glacier melt are extremely important hydrological processes in the ARNC, especially in the Kunlun and Tianshan mountains;(3) baseflow in the inland rivers of the ARNC is the result of climate change and human activities, with the main driving factors being the reduction in forest area and the over-exploitation and utilization of groundwater in the river basins; and(4) the contradictions among water resources, ecology and economy will further increase in the future. The findings of this study might also help strengthen the ecological, economic and social sustainable development in the study region.

A distributed runoff model for inland mountainous river basin of Northwest China

In order to predict the futuristic runoff under global warming, and to approach to the effects of vegetation on the ecological environment of the inland river mountainous watershed of Northwest China, the authors use the routine hydrometric data to create a distributed monthly model with some conceptual parameters, coupled with GIS and RS tools and data. The model takes sub-basin as the minimal confluent unit, divides the main soils of the basin into 3 layers, and identifies the vegetation types as forest and pasture. The data used in the model are precipitation, air temperature, runoff, soil weight water content, soil depth, soil bulk density, soil porosity, land cover, etc. The model holds that if the water amount is greater than the water content capacity, there will be surface runoff. The actual evaporation is proportional to the product of the potential evaporation and soil volume water content. The studied basin is Heihe mainstream mountainous basin, with a drainage area of 10,009 km 2 . The data used in this simulation are from Jan. 1980 to Dec. 1995, and the first 10 years' data are used to simulate, while the last 5 years' data are used to calibrate. For the simulation process, the Nash-Sutcliffe Equation, Balance Error and Explained Variance is 0.8681, 5.4008 and 0.8718 respectively, while for the calibration process, 0.8799, -0.5974 and 0.8800 respectively. The model results show that the futuristic runoff of Heihe river basin will increase a little. The snowmelt, glacier meltwater and the evaportranspiration will increase. The air temperature increment will make the permanent snow and glacier area diminish, and the snowline will rise. The vegetation, especially the forest in Heihe mountainous watershed, could lead to the evapotranspiration decrease of the watershed, adjust the runoff process, and increase the soil water content.

The Process of Cultivated Land and Water Resource Distribution Changing in Recent Decades in Upstream and Downstream in Shiyang Inland River Basin in Arid Area of Northwest China

Last century 50 - 70 years, the dam construction of Shiyang Inland River Basin (SIRB) profound impact on the distribution of water resources and arable land in the basin. Through data collection, field surveys and remote sensing image interpretation, we analysis the use of land and water resources change process in the middle and lower reaches of SIRB in recent decades. The results show: (1) The cultivated area of SIRB has been an upward trend in recent decades, The whole basin cultivated area has increased total 229,000 hm2 from 1973 to 2010 and mainly in the middle and lower reaches. Midstream increased by 149,700 hm2 accounting for 65.36 percent of total, downstream increased by 70,000 hm2 accounting for 30.70 percent of total. (2) The amount of surface water resources of downstream reduce significantly gradually since dam construction, and the water table sharp decline. While the volume of surface water resources come downstream from the 1950s accounted for 30 to 40 percent of the total gradually reduced to less than 10% in 2012;(3) since the arable land area of middle and lower reaches of SIRB basin substantial increase, so the surface water resource does not meet irrigation needs. Agricultural irrigation relies heavily on exploitation of groundwater to supplement, resulting in Regional Groundwater Depth dropped rapidly, and forming several huge funnel groundwater settlements. 20 years from 1981 to 2001 the groundwater level of midstream dropped from around 5m to around 10m in Wuwei, and in Minqin dam-region of downstream along faster rate of decline in 20 years fell from 8.52 m to 22.68 m. Dam construction project has changed the pattern of the basin water cycle, the middle reaches closure a large number of surface water resources led to downstream sharp decline. Downstream continued exploitation of groundwater formed a few huge funnel groundwater settlements, it caused serious ecological problems. The basin should adjust the industrial structure and develop water saving irrigation, promote a virtuous cycle of water resources, to achieve sustainable development, seek a sustainable development ways conversion natural oasis to artificial oasis efficiency in arid zone.

河西内陆河流域生态屏障建设综合评价与提升策略研究

生态屏障建设是推进人与自然和谐共生的中国式现代化的重要手段,内陆河流域生态屏障建设评价对于总结生态屏障建设成效与问题及落实中国式现代化建设战略任务具有重要意义。基于社会—生态耦合视角,在构建生态屏障建设评价指标体系基础上,运用综合指数法,对2015—2020年河西内陆河流域生态屏障建设状况进行了动态综合评价,并据此提出提升策略。结果表明:(1)河西内陆河流域生态屏障建设综合指数呈小幅上升态势,生态屏障建设处于发展提升阶段,流域生态安全多处于一般和较差状态;(2)流域生态屏障建设成效空间上整体呈现出自西往东逐渐下降的趋势,其中张掖市生态屏障建设成效明显,生态屏障建设综合指数稳步提升。基于上述研究,建议从社会—生态系统整体性出发,将生态屏障建设融入流域建设全过程,在生态产业、生态文化和生态社会等方面进行整体谋划和系统安排,统筹推进流域生态屏障建设转型提升。

Impacts of land use changes on groundwater resources in the Heihe River Basin

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.

The coordinated development of China’s inland water transport

The coordinated development is the core of sustainable development and the hot issue of international research.Inland water transport(IWT) is an important part of the water resources exploiting system and comprehensive transport system under socio-economic context of river basin,and also the country's sustainable development priorities to achieve resource-conserving and environment-friendly strategy.Based on the coordinated development content,the paper combined Germany's successful development experience,explored the elements and problem of the coordinated development of IWT system of China's national economic strategy and basin economy,water resourse system,comprehensive transport system,and system itself,and their countermeasures and suggestions,in order to facilitate rapid and coordinated development of China's inland water transport.

Response of Glacier and Lake Covariations to Climate Change in Mapam Yumco Basin on Tibetan Plateau during 1974-2003

The study of spatial and temporal covariances of glaciers and lakes would help us to understand the impact of climate change within a basin in Tibet. This study focuses on glacier and lake variations in the Mapam Yumco （玛旁雍错） basin （covering 7 786.44 km^2） by integrating series of spatial data from topographic maps and digital satellite images at four different times： 1974, 1990, 1999, and 2003. The results indicate that： （1） decreased lakes, retreated glaciers, enlarged lakes and advanced glaciers co-exist in the basin during the last 30 years; （2） glacier recession was accelerated in recent years due to the warmer climate; （3） lake areas in the basin are both reduced and enlarged by an accelerated speed with more water supplies from speeding melt glaciers or frozen ground in the last three decades.

WRF-Hydro模型参数在河西内陆河流域的敏感性分析

为研究WRF-Hydro模型参数在河西内陆河流域的敏感性,以西营河流域九条岭水文站以上区域为研究区,在离线模式下利用2015—2018年的全球预报系统(GFS)数据驱动WRF-Hydro模型。基于LH-OAT方法对WRF-Hydro模型的6个主要参数对不同评价指标和空间分辨率的汇流演算网格的敏感性进行了分析,定量计算了各参数的敏感性指标,划分了敏感度等级,并结合典型洪水分析了各参数对洪水过程线的具体影响。结果表明:河道曼宁糙率乘子(MANNFAC)为极敏感参数,入渗系数(REFKDT)、土壤饱和导水率(REFDK)、深层导水系数(slope)为敏感参数,地表糙率乘子(OVROUGHRTFAC)为一般敏感参数,地表持水深度乘子(RETDEPRTFAC)为不敏感参数;各参数的敏感性并不是一成不变的,参数敏感度会受到评价指标的影响,有一定程度的变化;随着汇流演算网格空间分辨率的变化,各参数全局敏感度也会有小幅变化,但参数的全局敏感度等级不发生改变;MANNFAC对峰现时间的调节效果最好,REFKDT和REFDK对洪量和洪峰流量的调节效果显著,slope可以很好地调节洪水过程线的形状。

Sentinel-2和ICESat-2密集时序数据反演浅平型内陆湖泊水量变化

干旱区内陆尾闾湖泊由于湖盆地形浅平、岸线复杂等特点,采用传统的水位-面积关系法难以反演高精度的水量变化信息。本文提出了一种基于密集时序ICESat-2和Sentinel-2数据反演浅平型内陆湖泊湖盆地形和重建水量时序的方法。本文方法利用浅平型湖泊季节性变化显著的特性,筛选和计算不同时期湖盆内非水面区域的所有ICESat-2激光光子点的高程信息,并根据水面等高的特性内插得到Sentinel-2不同时相水面线的高程信息,在此基础上通过这些加密的高程点构建高精度湖盆地形信息,并结合水面时序重建湖泊的水量变化。以新疆塔里木河尾闾台特玛湖为试验区,基于132期Sentinel-2卫星影像和28个时相的ICESat-2激光脉冲数据,重建了2016—2022年的湖泊水量时序。结果表明,本文方法获取的湖盆地形高程中误差为0.103 m,可为无资料浅平型湖泊水量信息的时序重建提供一种思路。

微功耗无值守的水资源监测浮标系统建设

系统介绍了自主设计开发的微功耗水资源在线监测浮标的工作运行原理、总体设计、子系统配置、多参数功能实现等内容,总结了微功耗水资源在线监测浮标系统的核心技术组成以及各模块功能设计要求,并简述了该浮标系统在南水北调东线京杭运河段的示范应用。

从内陆到边疆:环境史视域下中国流域文明的内生与互动

中国地势的三大阶梯塑造了内陆水系和边疆国际河流之间流域地理和河流景观的巨大差异,各流域在民族群体、社会、经济、文化等方面内生出丰富多元的流域文明。根据各流域文明在不同时空范围的跨流域传播和互动效应,以中原文化和农耕经济等为代表的内陆流域文明不断辐射和凝聚边疆跨境流域文明,使各流域文明由异质性趋于同质性发展。在此过程中,流域文明强化了以“中国”为中心的文明共性和国家认同,构成中华文明“多元一体”的发展格局,从内陆繁荣到边疆稳定的国家统一进程中,各流域文明发挥了重要的整合功能。

冻结期和冻融期土壤水分运移特征分析

西北内陆盆地冻结期和冻融期几乎占全年时间的 1 /2 ,该时期土壤水分运移特点与非冻结期存在较大差异。本文根据北疆昌吉平原区土壤水分运移观测试验 ,分析了冻结期和冻融期土壤水势分布和土壤含水量变化规律及其与潜水的转化关系 ,并阐述了冻融水的生态环境意义。

中国陆内俯冲(C-俯冲)观的形成和发展

自1984年首次提出C-俯冲(中国陆内俯冲———Chinese-Subduction之简称)观点后,引起了国内地学界强烈的反响。经过近20年的发展,这一观点已被越来越多的地质现象证实,也被越来越多的人们所接受。这一观点认为,C-俯冲带在大地构造位置上处于古老褶皱山系与内陆盆地边缘坳陷之间;C-俯冲带早期为正断层,后期转化为逆断层,成为盆地坳陷边缘主动向山系潜滑的俯冲断层;C-俯冲带有着良好的成油条件,在逆冲带形成早期往往发育着较厚海相和海陆过渡相沉积,后期形成前渊盆地,在中、新生代可形成良好的湖相成油环境;青藏高原的崛起除了与新生代印度板块与欧亚板块发生碰撞有关外,还与龙门山C-俯冲活动有关;C-俯冲不仅在中国中西部存在,也存在于中国的东部地区,C-俯冲观点的提出,丰富、完善了板块学说关于中、新生代造山带形成的模式,是中国地学工作者在大陆构造理论上的创新。