• 全国中文核心期刊
  • 中国科技核心期刊
  • 美国工程索引(EI)收录期刊

2021 Vol. 32, No. 1

Display Method:
Dynamic changes of typical glacier-fed lakes in different climatic zones around the world from 1995 to 2015
LIU Jiping, JIN Jing, LI Shengming, SONG Kaishan
2021, 32(1): 1-9. doi: 10.14042/j.cnki.32.1309.2021.01.001
Abstract:
Based on Landsat images captured in 1995, 2005 and 2015, a study was conducted in this paper on the typical glacier-fed lakes located in different climatic zones globally for their area, quantity and response to climate change, with the assistance of RS (Remote Sensing) and GIS(Geographic Information System). The results showed that:① The area of globally typical glacier-fed lakes increased by 2.32%, but the number of them declined by 2.26% during the period from 1995 to 2015. The area of small (< 1 km2) and great lakes(>50 km2) showed the most significant changes, while those medium-size lakes(1-50 km2) were shown to be relatively stable, with the area and number of glacier-fed lakes changing at a faster pace than in the period from 2005 to 2015.② The area and number of glacier-fed lakes in tropical, subtropical and temperate zones exhibited an increasing trend from 1995 to 2015. Particularly, the glacier-fed lakes in tropical zone showed the most significant change as the area covered by them increased by 20.62% and the number of them rose 25.32%. By contrast, the area and number of glacier-fed lakes in subfrigid zone and frigid zone exhibited a decreasing trend. More specifically, the glacier-fed lakes in frigid zone showed the most evident change as the area and number of glacier-fed lakes in frigid zone was reduced by 11.3% and 18.97%, respectively. This paper provides basis and reference for subsequtial studies on the changes to glacier-fed lakes and the influencing factors for these changes.
Precipitation concentration characteristics in China during 1960—2017
LIU Xiangpei, TONG Xiaohui, JIA Qingyu, XIN Zhuohang, YANG Jianren
2021, 32(1): 10-19. doi: 10.14042/j.cnki.32.1309.2021.01.002
Abstract:
Precipitation concentration is an important component of precipitation structure. The present study uses daily precipitation data from 1960—2017 to calculate the precipitation concentration index Q and investigate in detail the spatial and temporal characteristics of precipitation concentration in China. In particular, this analysis considers how precipitation concentration is related to both precipitation amount and maritime conditions. The results indicate that China's yearly mean Q value is 0.38, with Q values highest in central China and lower in northern and southern China. Precipitation concentration is higher in winter and autumn, with mean Q values of 0.53 and 0.51, respectively; in contrast, the mean Q values for summer and spring are 0.39 and 0.48, respectively. For China as a whole, the yearly mean Q value is increasing slowly with time; however, yearly mean Q trends exhibit regional variation, with positive and negative temporal trends in southeastern and northwestern China, respectively. The results indicate a negative correlation between precipitation concentration and precipitation amount at both annual and seasonal scales (correlation coefficient of-0.71 at the annual scale). This correlation is strongest in autumn and weakest in winter (correlation coefficients of -0.89 and-0.70, respectively). Moreover, both precipitation concentration and precipitation amount control the area affected by flood and drought. The correlation coefficient between yearly Q and the NINO3.4 index increases and then decreases with increasing lag time, with the strongest correlation (coefficient:0.13) found for a lag time of 2 months. This correlation also exhibits a distinct spatial pattern, with a "-+-" distribution from north to south. Similarly, the correlation coefficient between yearly Q and the Pacific Decadal Oscillation increases and then decreases with increasing lag time; this correlation is strongest (coefficient:0.12) for a lag time of 4 months. This relationship exhibits a negative correlation across most of China.
Distributed hydrological model of the Qinghai Tibet Plateau based on the hydrothermal coupling: Ⅰ: hydrothermal coupling simulation of "snow-soil-sand gravel layer" continuum
ZHOU Zuhao, LIU Yangli, LI Yuqing, WANG Pengxiang, WANG Kang, LI Jia, ZHU Yiming, LIU Jiajia, WANG Fuqiang
2021, 32(1): 20-32. doi: 10.14042/j.cnki.32.1309.2021.01.003
Abstract:
The Qinghai-Tibet Plateau, known as the "Asian Water Tower", is a typical alpine mountain area. Snow-covered permafrost and seasonally frozen soil widely exist on this plateau, profoundly affecting the water cycle process of the entire region. In addition, the Qinghai-Tibet Plateau has the characteristics of a thinner soil layer and a thicker underlying sand and gravel layer, forming a special "snow-soil-sand gravel layer" hydrothermal medium structure. To further study the water cycle mechanism of the Qinghai-Tibet Plateau, this study selected the Niyang River basin as a typical area to perform field-heat-coupling experiments in the field. Combined with the geological and climatic characteristics of the Qinghai-Tibet Plateau, a 12-layer "snow-soil-sand gravel layer" continuum was constructed to describe the hydro-thermal coupling model of the Qinghai-Tibet Plateau. A complete hydro-thermal coupling simulation equation and parameter calculation method are described. The model was validated using the measured results of the temperature, liquid water content, and freezing depth of the soil and gravel layer in the freezing and thawing period of 0-160 cm from 2016 to 2017. The mean values of the simulated R2 of the temperature of each layer and the moisture content during freezing and thawing were 0.91 and 0.52, respectively. The R2 of the soil freezing depth is 0.76. The results show that the model can better reflect the hydrothermal variation of stratified soil and sand gravel during freezing and thawing processes. The results show that the model has adequate applicability in the Qinghai-Tibet Plateau and can reflect the special change process of moisture and temperature of the soil and gravel layer during the freezing and melting processes in this area.
New model for water resources spatial equilibrium evaluation and its application
YANG Yafeng, GONG Shuxin, WANG Hongrui, ZHAO Ziyang, YANG Bo
2021, 32(1): 33-44. doi: 10.14042/j.cnki.32.1309.2021.01.004
Abstract:
To mitigate the insufficient consideration of fuzziness and dynamic conditions in water resources spatial equilibrium evaluation, a new model for water resources spatial equilibrium evaluation was developed based on the concept of variable set and partial connection number. The relative membership degree and level characteristic value of the evaluation object were calculated by the variable set evaluation method; The information evolution and its influence on the levels were described by the partial connection number method in order to obtain the rating strategy based on the maximum support principle. The two methods' results were integrated to evaluate the spatial equilibrium state of water resources. The results of application to 31 Chinese provinces in 2017 show that:① the spatial equilibrium of water resources in the Southeast of China is in good conditions, while the Northwest is in a relatively poor condition. The South has better conditions than the North and the East has better conditions than the West; ② The water resources spatial equilibrium situation of 17 provincial administrative regions, including Beijing, present a worsening trend, which calls for further strengthening of management. The other areas present a benign developing trend; ③ In some provinces, such as Sichuan and Shaanxi, the equilibrium degree of each index is quite different, which suggests a need to be adjusted and optimized.
Happy River evaluation system and its application
ZUO Qiting, HAO Minghui, JIANG Long, ZHANG Zhizhuo
2021, 32(1): 45-58. doi: 10.14042/j.cnki.32.1309.2021.01.005
Abstract:
The construction of rivers into Happy Rivers is a new goal for river management in China in the new era, which is of great significance for sustainable development of river health and the society. The present study further evaluated the concept of a Happy River and proposed a Happy River evaluation system. The evaluation system is based on the framework of the "Four Major Judgment Criteria", namely, safe operation, continuous supply, ecological health, and harmonious development, and included 16 and 34 basic and alternative indicators, respectively, according to the three levels of "goal-criteria-indicator". By referencing the large number of normative and standard documents along with the research results, five levels of Happy River grading standards were proposed for each indicator. The "Happy River Index" was introduced for quantitative evaluation of river status, and the "single index quantification-multiple indices synthesis-poly-criteria integration" method was used to calculate the index; Finally, the evaluation system was applied to the Yellow River, China for 2017, including the Yellow River segment, nine provinces, and the Weihe River tributary. The present study verified that the proposed evaluation system accurately represented the Happy River status of the Yellow River, and the evaluation system is therefore reliable and applicable.
Dynamic prediction and regulation of water resource carrying capacity: a case study on the Yellow River basin
HUANG Changshuo, GENG Leihua, YAN Bing, BIAN Jinyu, ZHAO Yuting
2021, 32(1): 59-67. doi: 10.14042/j.cnki.32.1309.2021.01.006
Abstract:
This study aimed to established the water resource carrying capacity of the Yellow River basin (YRB), China in respect to water quantity and quality to facilitate accurate prediction of changes in regional water resources carrying capacity and to formulate an optimal control plan based on the "economic society-water resources-ecological environment" mutual feedback mechanism. Various methods, including element diagnosis, identifying indicators of key drivers, integrating support vector machines and system dynamics were applied to establish a quantitative dynamic water resources carrying capacity simulation model for the YRB by formulating control objectives and analyzing the difficulty and cost of managing drivers of carrying capacity. The orthogonal test method was applied to improve the capacity and reduce load within the YRB. The six indicators of key drivers chosen were:① unconventional water utilization; ② seawater intake; ③ average irrigation water consumption; ④ irrigation area; ⑤ industrial value-added water consumption; ⑥ 10, 000 yuan industrial value-added water consumption. The simulation results showed that the upstream, middle and downstream areas of the YRB are currently in an overloaded or severely overloaded state at all planned levels before water transfer projects such as the West Route of South-to-North Water Transfer Project become effective. The study identified the optimal control plan to avoid overloading of the annual water carrying capacity of the YRB at all levels and provides scientific guidance for water resources management of the YRB.
Potential role of coordinated operation of transboundary multi-reservoir system to reduce flood risk in the Lancang-Mekong River basin
HOU Shiyu, TIAN Fuqiang, LU Ying, NI Guangheng, LU Hui, LIU Hui, WEI Jing
2021, 32(1): 68-78. doi: 10.14042/j.cnki.32.1309.2021.01.007
Abstract:
The Lancang-Mekong River (LMR) basin has historically been affected by severe floods and is likely to suffer further flood events with higher peaks and longer duration in the future due to climate change, which calls for collective action to respond. This study examined the potential flood control effect of coordinated operation of the LMR transboundary multi-reservoir system by establishing a distributed hydrological model coupled with a reservoir operating model, simulating the runoff of 13 tributaries and 5 mainstream sections. Results show that:① Flood magnitude at the five sections along the Mekong River is significantly reduced by mitigating flood recurrence from 200 years to 20-50 years.② In terms of flood control, the left-bank tributaries contribute more than the right bank. Tributaries with relatively higher flood control capacity are:Lancang, Nam Ou, Nam Ngum and Nam Theun, Nam Mun, Se Kong and Se San. ③ Different tributaries play a major role in flood control across regions. Luang Prabang's main flood control tributaries are Lancang and Nam Ou. At Nakhon Phanom, Lancang's flood control contribution is same as Nam Ngum and Nam Theun's sum. In the downstream of Pakse, the flood control contribution of Nam Mun and Se Kong are higher than Lancang. This research provides a reference for transboundary flood control cooperation between riparian countries, which face an important opportunity underpinned by the Lancang-Mekong Cooperation Mechanism (LMC).
Experimental study on rheological properties of soft mud in Yangtze River Estuary
JIANG Qin, CUI Li, NIE Sihang, FAN Shuming, YING Ming
2021, 32(1): 79-87. doi: 10.14042/j.cnki.32.1309.2021.01.008
Abstract:
In order to clarify the soil mechanical properties of soft mud in the Yangtze River Estuary under shear loads, experimental study by using Anton Paar MCR302 rotary rheometer was conducted to examine the rheological responses of the mud to shear forces, especially on the basic rheological property of the mud with bulk density ranging from 1.16 to 1.72 g/cm3, as well as the associated influences of bulk density, salinity, pH value and temperature. The results showed that under the action of shear loads, the mud in the Yangtze River Estuary exhibits Bingham fluid characteristics, and the relationship between shear stress and shear rate can be quantitatively described based upon the Dual-herschel-bulkley rheological model. With the increase of shear rate, the complex phase transformation process from solid to liquid of the mud was observed which can be classified into three typical stages:solid-like stage, solid-liquid transition stage and liquid-like stage, corresponding to the elastic, viscoelastic and plastic material respectively. The shear strength of the mud increases with the increase of bulk density, salinity and pH value, and decreases with the increase of temperature. Finally, with the measured results, an empirical constitutive equation was established to describe the rheological behaviors of the mud, that can be applied for quantitative analysis of the mud movement under hydrodynamic forces such as tides and waves.
Numerical simulation of the wave-driven solute transport in deformable seabed
LIU Xiaoli, LIU Mingzhu
2021, 32(1): 88-96. doi: 10.14042/j.cnki.32.1309.2021.01.009
Abstract:
The process of solute transport into marine sediments from overlying water can be accelerated by waves. However, the effect of wave-induced deformation of seabed on solute transport has been ignored in most investigations. In response this paper investigates the influence of sandy bed deformation on the mechanism of solute transport using a modified solution-transport numerical model, in which the process of solute transport into deformable marine sediments from overlying water could be simulated under progressive waves. The results have shown that the seabed deformation will increase the velocity of pore water, which in turn increases the vertical hydrodynamic dispersion coefficient and the mechanical dispersion of solute transport. Therefore, the wave-induced deformation of soil will advance the process of solute migration into marine sediments. Case studies have indicated that in deformable soil the maximum vertical hydrodynamic dispersion coefficient could be 8.5 times that ignoring soil deformation, and about 545 times the molecular diffusion coefficient. The smaller the shear modulus of seabed soil, the more obvious soil deformation occurs, and the greater the influence of soil deformation has on solute transport. Furthermore, the reduction of degree of saturation will advance the solute transport into marine sediments.
Experimental study on sheet erosion process of loess and its suitability of hydraulic parameters on gentle slopes
HE Jijun, WANG Shuo, CAI Qiangguo, SUN Liying, LI Xueqing
2021, 32(1): 97-108. doi: 10.14042/j.cnki.32.1309.2021.01.010
Abstract:
In order to determine erosion-limited conditions and the suitability of hydraulic parameters in sheet erosion of loess gentle slope, simulated rainfall test was used in this study, under condition of 60 mm/h rainfall intensity, 3 slopes (7.5°, 10°, 15°) and 2 slope lengths (5 m and 10 m), to verify the feasibility of sediment concentration as a characterization parameter to determine the erosion-limited conditions in the process of sheet erosion, and to propose an evaluation method to test the suitability of the relationship between hydraulic parameters and sediment yield. The test results showed that sheet erosion process could be divided into three erosion stages:transport-limited stage, detachment-limited stage Ⅰ and detachment-limited stage Ⅱ according to the change of sediment concentration with runoff, and the amount of erosion in detachment-limited stage Ⅰ was dominant absolutely. For the suitability of hydraulic parameters, both stream power and Reynolds number could well characterize the relationship with sediment yield, while flow shear stress and Froude number could not effectively reflect the relationship with sediment yield. In different erosion-limited stages, steam power and Reynolds number have different relationship with sediment yield. In the transport-limited stage and detachment-limited stage Ⅱ, steam power and Reynolds number showed exponential and linear positive correlation with sediment yield, respectively. In the detachment-limited stage Ⅰ, stream power and Reynolds number had a linear negative correlation with sediment yield, but the interaction was not unique, with different slope length and Reynolds number critical value. That is, in the transport-limited stage and detachment-limited stage Ⅱ, the relationship between stream power, the Reynolds number and the sediment yield was not affected by the effect of slope length; in the detachment-limited stage Ⅰ, the joint influence of slope length and the critical value of Reynolds number should be considered simultaneously. The results of this study can provide valuable information for a better understand of the complexity of sheet erosion process.
Simulating long-term soil water balance in response to land use change in the Northern China's Loess Plateau
BAI Xiao, JIA Xiaoxu, SHAO Ming'an, ZHAO Chunlei
2021, 32(1): 109-119. doi: 10.14042/j.cnki.32.1309.2021.01.011
Abstract:
To explore the impact of land-use change on the long-term soil water balance in Northern China's Loess Plateau, we used the Hydrus-1D model to simulate the soil water dynamics at depths of 0—4 m under the scenario of arable land-alfalfa land-natural grassland located in the Liudaogou watershed. The evolution characteristics of hydrological variables including soil water storage, deep seepage and evapotranspiration were quantified from 1981 to 2050. The results showed that soil water fluctuated with rainfall levels during arable land periods, with 88% of the annual precipitation consumed through evapotranspiration, and 11% was lost to deep seepage. The first stage of soil water change during the alfalfa land period was 1—6 years after plantation, during this period, evapotranspiration accounted for 108% of the annual rainfall, leaving the soil water in a negative balance. And the soil water storage of 0—4 m decreased at a rate of 52 mm/a. The second stage was 7—13 years after plantation, almost all rainfall was consumed by evapotranspiration. Eight years after alfalfa land transitioned into natural grassland, annual evapotranspiration decreased by 31%, and soil water storage gradually recharged at 45 mm/a. Subsequently, 92% of the annual rainfall was used for evapotranspiration, with the remaining 8% was lost to deep seepage. The soil water remained in a relatively stable state. These indicated that the soil water balance modes varied under different vegetation types. Planting vegetation with high-water-consumption could cause negative balance of soil water and led to serious soil desiccation, which then had a negative effect on soil water supply. However, the formed dry soil layer could be completely restored by changing the vegetation type.
A watershed runoff yield model based on Erlang distribution water storage capacity curve
YAN Baowei, LI Zhengkun, DUAN Meizhuang, JIANG Huining, LIU Yu
2021, 32(1): 120-126. doi: 10.14042/j.cnki.32.1309.2021.01.012
Abstract:
A storage capacity curve reflects the spatial heterogeneity in water deficiency within a basin and is used for computing the production of watershed runoff. This study analyzed the spatial distributions of watershed storage capacity for several typical basins. The Erlang distribution was shown to have the best fit to the watershed storage capacity curves, which was then adopted to derive the production of runoff in the studied watersheds. This study proposes a novel watershed runoff yield model with increased adaptability based on the Erlang distribution storage capacity curve; hence, the model should be better able to represent the actual runoff yield process in a basin. The proposed watershed runoff yield model generated more accurate simulations compared to those of the Xin'anjiang model. In addition, the parameters of the proposed runoff yield model can be estimated from basin topography and soil type data, thereby providing a feasible approach for the calculation of runoff yield in data-scarce areas.
Relationship between water salinity and vegetation distribution in the Tiaozini reclamation area
ZHAN Lucheng, MA Fenyan, CHEN Jiansheng, XIN Pei
2021, 32(1): 127-138. doi: 10.14042/j.cnki.32.1309.2021.01.013
Abstract:
To investigate the water and salt distribution, and explore the relationship between vegetation circles and soil water salinity conditions in the Tiaozini reclamation area of Dongtai, Jiangsu, a measurement and sampling campaign was conducted in a reclaimed zone used for wetland restoration in September 2019. Electrical resistivity tomography (2-D and 3-D) was conducted near the plant circles. Precipitation, surface water, soil profiles, and shallow groundwater samples were collected and analyzed for water and salt parameters as well as for D and 18O isotopic compositions. The results show that low resistivities and high salinity zones exist underneath the plant circles within 3 m of depth, and soil water salinity increases with the plant type, changing from the center of the circle to the outer area. Soil water salinity is an essential factor for the circular distribution of different plant types. Spatial variation of surface soil water salinity results from both precipitation infiltration and salt accumulation caused by evaporation. Soil salinity affects the distribution pattern of different plant types, while plants can also influence the salinity distribution by affecting the infiltration and evaporation processes.
Reality and problems of controlling soil water and salt in farmland
WANG Quanjiu, DENG Mingjiang, NING Songrui, SUN Yan
2021, 32(1): 139-147. doi: 10.14042/j.cnki.32.1309.2021.01.014
Abstract:
Soil salinization in farmland is one of the main problems that threaten the sustainable development of agriculture. In order to develop a method for controlling soil water and salt in farmland and adapt to the needs of modern ecological agriculture, the source of salt and its cumulative dynamic characteristics in farmland were analyzed in this study. The effects of soil salt on the nutrient supply capacity of soils and the crop production capacity were analyzed to demonstrate the associated regulatory directions in the soil-crop system. According to the ideas for controlling soil water and salt at different times, the processes for regulating soil water and salt in farmland were divided into four stages, where the mechanism and control objectives in terms of water conservation measures, chemical measures, biological measures and agronomic measures were analyzed to assess the control of salt-alkali damage to soil and crops. According to the requirements for modern agricultural development, the ideas for controlling soil water and salt in farmland were developed by regulating the dynamic characteristics of soil water and salt transport, reconstructing the spatial distribution of soil water and salt and enhancing the effectiveness of crop growth adjustment measures. This study also identified the key technical issues that need to be addressed urgently to allow the green regulation of soil water and salt in farmland, and the basic scientific problems that need to be investigated in order to develop a theory of soil water and salt regulation, thereby providing guidance to facilitate the production of efficient and sustainable agroecosystems under saline-alkali stress.
Application of Copula functions in hydrology and water resources: a state-of-the-art review
LIU Zhangjun, GUO Shenglian, XU Xinfa, XU Shichao, CHENG Jingqing
2021, 32(1): 148-159. doi: 10.14042/j.cnki.32.1309.2021.01.015
Abstract:
Copula functions, which are flexible tools for the derivation of joint probability distributions, have been widely and effectively used to deal with multivariable analysis problems in the field of hydrology and water resources. Particularly in recent decades, this method has received great attention from researchers and engineers because of its advantages in multivariate analysis where the marginals of the data are not normally distributed. This paper provides a state-of-the-art review of the last decade of copula functions in multivariate hydrological frequency analysis, coincidence and combination analysis of hydrological events, hydrological stochastic simulation, and hydrological modeling and forecasting, etc. More specifically, application issues such as parameter estimation, variable asymmetry, fitting optimization, tail characteristics, multivariable return period selection, and sampling error are described. Finally, the key points and development direction of Copula functions in the field of hydrology and water resources are considered, which provides guidance for the application of this method in the future.