scholarly journals Simulation of Actual Evapotranspiration and Evaluation of Three Complementary Relationships in the Upper Regions of the Mekong River and the Salween River

2021 ◽  
Author(s):  
Yongshan Jiang ◽  
Zhaofei Liu ◽  
Rui Wang ◽  
Pingcuo Gele
Keyword(s):  
Wind Speed ◽  
River Basin ◽  
Negative Correlation ◽  
Aridity Index ◽  
Actual Evapotranspiration ◽  
Upstream Region ◽  
Contribution Rate ◽  
Complementary Relationship ◽  
Annual Series ◽  
Downstream Region

Abstract Based on observed precipitation and runoff data, monthly actual evapotranspiration (ETa) was calculated by the hydrological budget balance method in the Nu River Basin (NRB) and Lancang River Basin (LCRB). The performance of three developed complementary relationship methods, the nonlinear advection-aridity (nonlinear AA) method, generalized complementary relationship method (B2015), and sigmoid generalized complementary function (H2018), on simulating (ETa) were evaluated. The evaluation results showed that three methods were able to accurately simulate monthly (ETa) series. The NSE between the monthly (ETa) simulated by the nonlinear AA, B2015, and H2018 methods and the water-balance-derived (ETa) were 0.89, 0.83, and 0.91, respectively. The R-square were 0.90, 0.84, and 0.93, respectively. Overall, the H2018 method showed the best performance. The parameter α had a negative correlation with regional aridity index. Annual (ETa) and precipitation showed significant increasing trends during 1956–2018 in the basins at all temporal scales (dry and wet seasons and annual series). Runoff also exhibited an increasing trend in each sub-basin, except for the downstream region of the LCRB. The increasing magnitudes of wet reason precipitation and runoff in the mid-stream region was the highest, with the value of 73.7 mm/10a and 44.9 mm/10a, respectively. The (ETa) increased dramatically in the downstream region, the magnitude reached 25.9 mm/10a. Precipitation was the main factor leasing to (ETa) change. The increasing magnitude of (ETa) accounted for 42.4% of the precipitation increment. Research on the influence mechanism between meteorological factors and (ETa) showed that the contribution rate of air temperature to (ETa) was the highest, reaching 23.5%, which showed a significant positive correlation. The second was wind speed, whose contribution rate was − 10.2% on average, and even reached − 14.1% in the upstream region of the NRB. The correlation coefficient between (ETa) and wind speed was highest in mid-stream region of the NRB, which was greater than 0.80. The contribution rates of increasing humidity to (ETa) were − 12.5% and − 9.2% in the NRB and LCRB, respectively. (ETa) was negatively correlated with humidity. The negative correlation was especially strong in the mid-stream region, with coefficients were greater than − 0.65. The sunshine hours had the least effect on (ETa), and the contribution rates were − 6.5% and − 4.1%, respectively.

scholarly journals Estimation of Actual Evapotranspiration by the Complementary Theory-Based Advection–Aridity Model in the Tarim River Basin, China

2018 ◽  
Vol 19 (2) ◽  
pp. 289-303 ◽  
Author(s):  
Dongnan Jian ◽  
Xiucang Li ◽  
Hemin Sun ◽  
Hui Tao ◽  
Tong Jiang ◽  
...  
Keyword(s):  
River Basin ◽  
Potential Evapotranspiration ◽  
Temporal Trends ◽  
Northwest China ◽  
Actual Evapotranspiration ◽  
Tarim River ◽  
Tarim River Basin ◽  
Complementary Relationship ◽  
The Tarim River ◽  
The Tarim River Basin

AbstractIn this study, the complementary relationship between actual evapotranspiration (ETa) and potential evapotranspiration (ETp) was verified in the Tarim River basin (TRB) in northwest China. The advection–aridity (AA) model that is based on the complementary relationship (CR) was used to calculate ETa. Spatial and temporal trends in the estimated annual ETa and the factors that influenced ETa were investigated. The multiyear average ETa in the TRB for the period from 1961 to 2014 was 178.5 mm. There was an overall significant increasing trend (at a rate of 10.6 mm decade−1) in ETa from 1961 to 2014; ETa increased at a rate of 22.9 mm decade−1 from 1961 to 1996 and decreased at a rate of 33.9 mm decade−1 from 1996 to 2014. Seasonally, ETa was strongest in summer, followed by spring and autumn. The spatial distributions of the annual and seasonal ETa were mostly consistent, with higher ETa values in the northeast, northwest, and southwest of the TRB, and lower ETa values in the mostly desert lands in the central and southeastern areas. While the energy budget (indicated by net radiation Rn) had little influence on ETa over time, the advection budget (indicated by the drying power of the air Ea) played an important role, explainable by Bouchet’s complementary relationship. In the Aksu River basin (ARB), ETa has increased because of an increase in the surface water supply (SWS). The change in ETa between 1996 and 1998 may have been caused by changes in the SWS and the advection budget during the same time period.

scholarly journals Dynamic Optimal Control Differential Game of Ecological Compensation for Multipollutant Transboundary Pollution

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Zhigang Chen ◽  
Qianyue Meng ◽  
Huichuan Wang ◽  
Rongwei Xu ◽  
Yongxi Yi ◽  
...  
Keyword(s):  
Differential Game ◽  
River Basin ◽  
Pollution Control ◽  
Transboundary Pollution ◽  
Upstream Region ◽  
Green Innovation ◽  
Ecological Compensation ◽  
Stackelberg Differential Game ◽  
Downstream Region ◽  
Compensation Rate

This paper studies a Stackelberg differential game between an upstream region and a downstream region for transboundary pollution control and ecological compensation in a river basin and increases the number of pollutants assumed in the model to multiple. Emission and green innovation investment between upstream and downstream regions in the same basin is a Stackelberg game, and the downstream region provides economic compensation for green innovation investment in the upstream region. The results show that there is an optimal ecological compensation rate, and a Pareto improvement result can be obtained by implementing ecological compensation. Increasing the proportion of ecological compensation can improve the nonvirtuous chain reaction between green innovation investment cost, pollutant transfer rate, and ecological compensation rate. Therefore, it is necessary to establish a joint mechanism composed of the government and the market and formulate a reasonable green innovation subsidy scheme according to the actual situation of the basin, so as to restrict the emergence of this “individual rational” behavior. For river basin areas that can establish a unified management department and organize the implementation of decision-making, the cooperative game is a very effective pollution control decision.

scholarly journals Separating the impacts of climate change and human activities on actual evapotranspiration in Aksu River Basin ecosystems, Northwest China

2018 ◽  
Vol 49 (6) ◽  
pp. 1740-1752 ◽  
Author(s):  
Peng Yang ◽  
Jun Xia ◽  
Chesheng Zhan ◽  
Xuejuan Chen ◽  
Yunfeng Qiao ◽  
...  
Keyword(s):  
Climate Change ◽  
Wind Speed ◽  
River Basin ◽  
Human Activity ◽  
Arable Land ◽  
Northwest China ◽  
Actual Evapotranspiration ◽  
Forest Land ◽  
Aksu River Basin ◽  
Impacts Of Climate Change

Abstract Separating the impacts of climate change and human activity on actual evapotranspiration (ET) is important for reducing comprehensive risk and improving the adaptability of water resource systems. In this study, the spatiotemporal distribution of actual ET in the Aksu River Basin, Northwest China, during the period 2000–2015 was evaluated using the Vegetation Interfaces Processes model and Moderate Resolution Imaging Spectroradiometer-Normalized Difference Vegetation Index. The impact of climate change and human activity on actual ET were separated and quantified. The results demonstrated that: (1) the annual pattern of actual ET per pixel exhibited the highest values for arable land (average 362.4 mm/a/pixel), followed by forest land and grassland (average of 159.6 and 142.8 mm/a/pixel, respectively). Significant increasing linear trends (p < 0.05) of 3.2 and 1.8 mm/a were detected in the arable land and forest land time series, respectively; (2) precipitation was the most significant of the selected climate factors (precipitation, average temperature, sunshine duration, and wind speed) for all ecosystems. The second most significant was wind speed; (3) human activity caused 89%, 98%, and 80% of the changes in actual ET of forest, grass, and arable land, respectively, while climate change caused 11%, 2%, and 20% of the changes in actual ET, in the Aksu River Basin during 2000–2015.

scholarly journals A Differential Game of Transboundary Pollution Control and Ecological Compensation in a River Basin

Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-13 ◽  
Author(s):  
Yongxi Yi ◽  
Zhongjun Wei ◽  
Chunyan Fu
Keyword(s):  
Differential Game ◽  
River Basin ◽  
Pollution Control ◽  
Learning By Doing ◽  
Upstream Region ◽  
Ecological Compensation ◽  
Investment Activity ◽  
Downstream Region ◽  
Investment Level ◽  
Compensation Rate

This paper investigates a Stackelberg differential game between an upstream region and a downstream region for transboundary pollution control and ecological compensation (EC) in a river basin. Among them, the downstream region as the leader chooses its abatement investment level and an ecological compensation rate to encourage upstream investing in water pollution control firstly. After then, the upstream region as the follower determines its abatement investment level to maximize welfare. FFurthermore, we take into consideration the effects of efficiency-improving and cost-reducing learning by doing which are originated from abatement investment activity of both regions simultaneously. The results show the following. (i) There is an optimal ecological compensation rate and under which a Pareto improvement result can be obtained. (ii) Carrying out EC will shift some abatement investment from the downstream region into the upstream region. (iii) The efficiency-improving and cost-reducing learning by doing derived from abatement investment activity of both regions can decrease the optimal ecological compensation rate, increase abatement investment,and improve the social welfare.

scholarly journals Complementary relationship estimation of actual evapotranspiration in extreme cold and arid areas: a case study of the Hotan River Basin, northwest China

2017 ◽  
Vol 49 (5) ◽  
pp. 1540-1558
Author(s):  
Xiaolong Zhang ◽  
Bing Shen ◽  
Lingmei Huang ◽  
Changsen Zhao ◽  
Jiqiang Lyu ◽  
...  
Keyword(s):  
River Basin ◽  
Time Scales ◽  
Meteorological Data ◽  
Remote Sensing Data ◽  
Northwest China ◽  
Actual Evapotranspiration ◽  
Observation Data ◽  
Complementary Relationship ◽  
Mountainous Regions ◽  
Water Surplus

Abstract Application of complementary relationship (CR) approaches using only routine meteorological data is a very convenient method of estimating actual evapotranspiration (ETa). Reanalysis datasets and remote sensing data provide good tools to overcome the difficulties in obtaining observation data. This study of the Hotan River Basin (HRB) in northwest China serves as a prime example for estimation of ETa during 2006–2014 by using the modified generalized CR. Based on comparison and analysis, the maximum potential evaporation calculated by the Penman-based equation was adopted. The estimated ETa rates were verified using a regional water balance method at annual time scales because of the limited available data. The calibration parameter was calibrated based on the elevation and underlying surface types. The mean annual ETa ranged from 2.3 mm to 800 mm during 2006–2014. ETa rates in the plains regions were higher than those in the mountainous regions. Most of ETa was concentrated in the months of May to September. A water deficit occurred in the middle and lower regions, while a water surplus occurred in the upper regions. This study not only provided a new concept for calibration, but also a potential solution for different underlying surfaces and time scales.

scholarly journals The Reporter System for GPCR Assay with the Fission YeastSchizosaccharomyces pombe

Scientifica ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Shintaro Sasuga ◽  
Toshiya Osada
Keyword(s):  
Fluorescent Protein ◽  
Signal To Noise Ratio ◽  
Biological Activities ◽  
Inducible Promoter ◽  
Upstream Region ◽  
Reporter Plasmid ◽  
Reporter System ◽  
High Background ◽  
Downstream Region ◽  
Green Fluorescent

G protein-coupled receptors (GPCRs) are associated with a great variety of biological activities. Yeasts are often utilized as a host for heterologous GPCR assay. We engineered the intense reporter plasmids for fission yeast to produce green fluorescent protein (GFP) through its endogenous GPCR pathway. As a control region of GFP expression on the reporter plasmid, we focused on seven endogenous genes specifically activated through the pathway. When upstream regions of these genes were used as an inducible promoter in combination with LPI terminator, themam2upstream region produced GFP most rapidly and intensely despite the high background. Subsequently, LPI terminator was replaced with the corresponding downstream regions. The SPBC4.01 downstream region enhanced the response with the low background. Furthermore, combining SPBC4.01 downstream region with the sxa2 upstream region, the signal to noise ratio was obviously better than those of other regions. We also evaluated the time- and dose-dependent GFP productions of the strains transformed with the reporter plasmids. Finally, we exhibited a model of simplified GPCR assay with the reporter plasmid by expressing endogenous GPCR under the control of the foreign promoter.

The Concentration Characteristics of PM10 and PM2.5 in Eight Cities of China in March, 2013

2013 ◽  
Vol 807-809 ◽  
pp. 20-23 ◽  
Author(s):  
Tao Sheng ◽  
Jian Wu Shi ◽  
Sen Lin Tian ◽  
Li Mei Bi ◽  
Hao Deng ◽  
...  
Keyword(s):  
Air Quality ◽  
Wind Speed ◽  
Relative Humidity ◽  
Negative Correlation ◽  
Ambient Air ◽  
Quality Standard ◽  
Meteorological Factor ◽  
Urban Air ◽  
Ambient Air Quality ◽  
Ambient Air Quality Standard

According to the information of air quality which published by the urban air quality real-time publishing platform, the concentration characteristics of PM10 and PM2.5 were studied in Kunming (KM), Changsha (CS), Hangzhou (HZ), Shanghai (SH), Harbin (HEB), Beijing (BJ), Wuhan (WH) and Guangzhou (GZ). The results show that the concentrations of PM10 and PM2.5 exceeded the Ambient Air Quality Standard (GB3095-2012) in varying degrees in March, 2013. The concentrations of PM10 in Wuhan is the highest, reached 164μg/m3, exceeded the standard by 9.3%; the concentrations of PM2.5 is much higher in Wuhan, Changsha and Beijing, the average concentrations were 96μg/m3, 103μg/m3 and 110μg/m3, exceeded the standard by 28.0%, 37.3% and 46.7% respectively. The correlation of PM10 with PM2.5 in most of these cities was good in March. The correlation analysis of pollutant with meteorological factor in Hangzhou, Shanghai, Beijing and Guangzhou was also studied, the results show that the concentrations of PM10 and PM2.5 are weakly positive correlation with temperature in the four cities, negative correlation with relative humidity without Beijing, and negative correlation with wind speed.

scholarly journals Shock Structures Using the OBurnett Equations in Combination with the Holian Conjecture

Fluids ◽  
2021 ◽  
Vol 6 (12) ◽  
pp. 427
Author(s):  
Ravi Sudam Jadhav ◽  
Amit Agrawal
Keyword(s):  
Transport Coefficients ◽  
Quantitative Agreement ◽  
Upstream Region ◽  
Shock Propagation ◽  
Wave Flow ◽  
Temperature Relation ◽  
Downstream Region ◽  
Shock Profiles ◽  
Mach Numbers ◽  
Modified Theory

In the present work, we study the normal shock wave flow problem using a combination of the OBurnett equations and the Holian conjecture. The numerical results of the OBurnett equations for normal shocks established several fundamental aspects of the equations such as the thermodynamic consistency of the equations, and the existence of the heteroclinic trajectory and smooth shock structures at all Mach numbers. The shock profiles for the hydrodynamic field variables were found to be in quantitative agreement with the direct simulation Monte Carlo (DSMC) results in the upstream region, whereas further improvement was desirable in the downstream region of the shock. For the discrepancy in the downstream region, we conjecture that the viscosity–temperature relation (μ∝Tφ) needs to be modified in order to achieve increased dissipation and thereby achieve better agreement with the benchmark results in the downstream region. In this respect, we examine the Holian conjecture (HC), wherein transport coefficients (absolute viscosity and thermal conductivity) are evaluated using the temperature in the direction of shock propagation rather than the average temperature. The results of the modified theory (OBurnett + HC) are compared against the benchmark results and we find that the modified theory improves upon the OBurnett results, especially in the case of the heat flux shock profile. We find that the accuracy gain is marginal at lower Mach numbers, while the shock profiles are described better using the modified theory for the case of strong shocks.

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